WorldWideScience

Sample records for radon progeny exposure

  1. External gamma exposure to radon progeny in indoor air

    International Nuclear Information System (INIS)

    Fujimoto, Kenzo

    1985-01-01

    The external γ-exposure from radon progeny uniformly distributed in indoor air was estimated by a computer program that was developed. This program can calculate the fluence rate, exposure rate and average energy for any given point in a room of any given size. As numerical example, the exposure rate normalized to unit airborne activity is presented, together with the fluence-weighted and exposure-weighted average photon energies, for a room of representative geometry containing radon progeny in equilibrium. To cover other conditions encountered in practice, quantitative evaluations are additionally presented of the effect on the exposure brought by changes in certain parameters, such as equilibrium factor, wall thickness, room size and receptor position. The study has quantitatively substantiated the prevailing postulate that the effective dose equivalent due to external exposure resulting from normal indoor concentrations of airborne radon progeny in the room of representative geometry should only amount to 0.04 % of that from the internal exposure from the same sources, and that it should be of similarly negligible order compared with internal exposure also in the case of other room geometries. (author)

  2. Design of a recirculating radon progeny aerosol generation and animal exposure system

    International Nuclear Information System (INIS)

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

    1988-01-01

    Inhalation studies are being conducted at ITRI using laboratory animals exposed to radon-222 progeny attached to vector aerosols that are typical of indoor environments. The purpose of these studies is to identify the cells at risk from inhaled radon progeny and their locations within the respiratory tract. These studies require exposures up to 1000 working level months (WLM) within a few hours. Thus, large amounts of radium-226 are needed to produce the gaseous radon-222. A once-through-exposure-system was considered to be impractical because of statutory discharge limitations and the large amounts of radium that would be required. Therefore, a recirculating exposure system was designed and constructed that removes the aerosol after passing through the exposure chambers and recirculates purified air and radon. The purified radon is mixed with freshly evolving radon from a radon generator and passed Into a reaction-aging chamber where attachment of radon progeny to the vector aerosol occurs. The design includes: (1) 50-200 mg radium-226 in a radon generator, (2) 40 L/min total flow rate, (3) CO 2 removal, (4) reconstitution of oxygen tension and water vapor content to atmospheric levels, and (5) a trap for radon gas. A radon progeny exposure concentration in the range of 4,000 to 50,000 WL is being produced. (author)

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

    International Nuclear Information System (INIS)

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

    1994-01-01

    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

  4. Risk of lung cancer in animals following low exposures to Radon-222 progeny

    International Nuclear Information System (INIS)

    Duport, P.; Monchaux, G.; Morlier, J.P.

    1997-01-01

    Owing to the facts that a) large uncertainties affect the epidemiology of radon progeny-induced lung cancer in humans (especially at low exposures), and b) the rat is a good model for studying the carcinogenicity of radon progeny in humans, the risk of lung cancer following low exposures to low concentrations of radon progeny can be estimated from data obtained in the laboratory on rats exposed under controlled conditions. From the limited set of laboratory data on the induction of lung cancer in laboratory rats it appears that, at low exposures, the risk of lung cancer decreases with decreasing concentration, and that exposures of the order of 25 WLM, at an exposure rate of 2 WL do not produce any excess lung cancers. Since 20 WLM is a lifetime exposure comparable to those expected in occupational or indoors conditions and 2 WL is an exposure rate about 20 times higher dm current occupational exposures rates and 100 times higher than indoor ones, these observations may be indicative of threshold conditions for the induction of lung cancer by radon progeny. (author)

  5. Optimization of filtration for control of exposure to radon progeny

    International Nuclear Information System (INIS)

    Curling, C.A.; Rudnick, S.N.; Ryan, P.B.; Moeller, D.W.

    1989-01-01

    The theoretical optimization of filter characteristics that minimize an individual's dose from the inhalation of radon progeny is described. The computer simulation presented combines models for a well-mixed room, lung deposition, and lung dose equivalent. A modified form of the Jacobi-Porstendorfer room model and the Jacobi-Eisfeld lung dosimetry model are used for the simulation. The parameters of the filter that are optimized include the filter's solidity, thickness, and fiber diameter. Room ventilation, particle size distribution and concentration, and other factors are specified. The theoretical model is used to determine optimal filter characteristics for reducing the lung dose equivalent under specified room conditions. The resulting optimal design is a thin filter (0.1 - 0.7 mm) of low solidity (0.5 - 1.0%) and relatively large diameter fibers (30 - 100 μm). This model indicates that a significant reduction in the dose-equivalent rate can be achieved through the use of a properly designed recirculating filter system

  6. Enhancement of exposure to radon progeny as a consequence of passive smoking

    International Nuclear Information System (INIS)

    Moghissi, A.A.; Seiler, M.C.

    1989-01-01

    Among indoor air pollutants, radon and tobacco smoke take dominant positions. Because radon decay products have a relatively short residence time in air, the extent of the equilibrium between radon and its daughter products is linearly proportional to the carcinogenic risk, at least at low exposure levels. The relevant factor is the equilibrium factor F. This paper discusses the enhancement of radon exposure as a result of the presence of particulate matter originating from tobacco smoke. The presence of tobacco smoke provides a mechanism for radon progeny to be attached to inhalable particles and to remain in indoor air for a prolonged time. The results of our study indicate a significant increase in F as a consequence of passive smoking. These modeling efforts are consistent with the experimental data reported previously

  7. Assessment of dose due to exposure to indoor radon and thoron progeny

    Directory of Open Access Journals (Sweden)

    Prasad Ganesh

    2010-01-01

    Full Text Available The components of the effective dose through inhalation from radon and its progeny are important for human health since they contribute to more than 50% of the total radiation dose from natural sources. As a consequence, radon has been identified as the second leading cause of lung cancer after smoking. Radon and its short lived decay products (218Po, 214Pb, 214Bi, 214Po present in dwellings are a radiation hazard, particularly if such sources are concentrated in the enclosed areas like poorly ventilated houses and underground mines. The indoor radon, thoron, and progeny concentrations were measured in a small hilly town of Budhakedar and the surrounding area of Tehri Garhwal, India, by using LR-115 Type II plastic track detector in a twin cup radon dosimeter. The concentrations of radon progeny were measured as the highest in winter and the lowest in summer while the thoron progeny concentration was found maximum in rainy season and minimum in autumn. The annual exposure to the potential alpha energy of radon and thoron were found to vary from 0.04 WLM to 0.69 WLM with an average value of 0.29 WLM, and 0.03 WLM to 0.37 WLM with an aver- age value of 0.16 WLM, respectively. The annual effective dose due to the exposure to indoor radon and progeny in Budhakedar homes was found to vary from 0.16 mSv to 2.72 mSv with an average value of 1.14 mSv and the effective dose due to the exposure to thoron and progeny was found to vary from 0.18 mSv to 2.49 mSv with an average value of 1.05 mSv. The results of systematic study have been obtained by considering the room as a space in which the radon and thoron levels are directly related to the dynamic and static parameters.

  8. A radon progeny deposition model

    International Nuclear Information System (INIS)

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

    2010-01-01

    The next generation low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly 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 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.

  9. A Radon Progeny Deposition Model

    International Nuclear Information System (INIS)

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

    2011-01-01

    The next generation low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly 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 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Rosaline, E-mail: rosaline@barc.gov.in, E-mail: rosaline.mishra@gmail.com; Sapra, B. K. [Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Mayya, Y. S. [Indian Institute of Technology, Mumbai (India)

    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.

  11. Need for an integrated approach towards the assessment of radon, thoron and their progeny exposures

    International Nuclear Information System (INIS)

    Mayya, Y.S.

    2008-01-01

    Recent publications dealing with epidemiological studies on North American and European populations have indicated statistically significant lung cancer risk coefficients attributable to residential radon exposures. These are essentially based on radon gas itself as the quantitative measure of exposures. However, considering that true exposures depend upon the intricate mechanisms of decay product deposition in the lung, it is necessary to go for the assessment of decay products including their size distributions and deposition velocities. This approach is essential for assessing the risks of thoron and its decay products which is of considerable importance in the public domain and in the thorium fuel cycle. The recent development of deposition based progeny concentration measurement techniques appear to be best suited for radiological risk assessments both among occupational workers and general study populations. These provide an easy to wear alternative for radon inhalation dosimetry similar to TLDs for external gamma radiations. It is urgently required to characterize their performance under a variety of residential indoor and workplace conditions. This may be achieved through an integrated multi-parametric study programme involving measurements of radon, thoron and their progeny concentrations along with fine and coarse fractions and indoor source terms. This will not only in delineate the true exposure profiles and indoor parameters (e.g. deposition velocities and air exchange rates) in the country, but also will help in establishing deposition dosimetry as a basic technique for inhalation exposure estimations for occupational workers and subjects living in high background radiation areas

  12. Occupational exposure to radon progeny: Importance, experience with control, regulatory approaches

    International Nuclear Information System (INIS)

    Kraus, W.; Schwedt, J.

    2002-01-01

    An overview of possible occupational exposures to enhanced natural radiation in Germany is given, based on an analysis of the German Radiological Protection Commission. So far, the most significant exposure source is radon at underground and above ground workplaces. As a result of relevant regulations, in East Germany since the 70's a systematic monitoring of exposures to radon progeny has been introduced step by step in the uranium industry, in conventional ore mining, in show caves and mines, in enterprises for securing mining areas against subsidence, in radon spas and in water works in radon affected areas. Individual exposures have been assessed. The monitoring results for the period 1975-1998 are presented. Successful protection measures leading to a significant reduction of the exposures are discussed. using workplace monitoring results and registered occupancy times. In West Germany no regulations in this area were in force. Nevertheless, voluntary measuring programmes at similar workplaces were carried out. In case of unacceptable exposures successful protection measures were implemented. At present a systematic approach to control occupational exposures to radon is laid down in the European Directive 96/29/Euratom which has to be taken over in the national legislation to come. The expected number of workplaces to be included in the radiation protection system in Germany, the recommendable way of including different workplace types taking into account appropriate reference levels, and possible approaches to a graded system of workplace and individual monitoring are discussed in detail. (author)

  13. Health effects of inhaled radon progeny

    International Nuclear Information System (INIS)

    Monchaux, G.

    1997-01-01

    The relationship between an increased risk of lung cancer and exposure to radon progeny has been studied in eleven cohorts of underground workers, both in uranium and non uranium mines as well as in experimental animals. Risk estimates derived from miners studies are used to assess the risk of lung cancer in relation to exposure to indoor radon progeny. Human and animal experimental data are reviewed in the perspective of risk assessment for low exposure to radon progeny, in the conditions of the contemporary working environment as well as the indoor domestic environment. (authors)

  14. Evaluation of room air cleaners for the reduction of exposure and dose to indoor radon progeny

    International Nuclear Information System (INIS)

    Hopke, P.K.; Jensen, B.; Wasiolek, P.

    1994-01-01

    Since the proximate source of dose to the cells of the bronchial epithelium is the deposited radon progeny, the exposure and resulting dose could be reduced if the radon decay products were effectively removed from the indoor atmosphere. Thus, room air cleaners could be effective in reducing the risks associated with indoor radon. However, because of the short half-life of 218 Po, it grows back quickly and in the altered aerosol conditions that are produced by the presence of an air cleaner, the exposure/dose conditions as well as the magnitude of the dose can be substantially changed. To examine the nature of the exposure of individuals in normally occupied homes and to determine the effect of various types of room air cleaners on the exposure to and dose from the indoor radon progeny, a series of measurements have been made using an automated graded screen array system. Two extended experiments were performed in homes in Arnprior, Ontario and Parishville, NY, in which filtration systems, a positive ion electrostatic precipitator, and ioniser/fan systems have been tested for their ability to remove both airborne radioactivity and particles. In both experiments, measurements were made over one week periods with an air cleaner operating and the distributions of exposure are compared with measurements of the background conditions when no cleaner is functioning. The doses to both basal and secretory cells of the bronchial epithelium in the first eight generations of the bronchus were calculated using the model developed by James and their distributions are compared among the various exposure conditions. In most cases the presence of the air cleaner reduced the exposure to radon progeny. However, the reductions in dose were generally substantially smaller than the reductions in exposure. In the intercomparisons of the two filtration units and the two identical ioniser/fan systems, the units generally behaved in a similar manner. The results of this substantial set of

  15. Radon Progeny in Egyptian Underground Phosphate Mines

    International Nuclear Information System (INIS)

    El-Hady, M.A.; Mohammed, A.; El-Hussein, A.; Ali, A.E.; Ahmed, A.A.

    2001-01-01

    In addition to the workers in uranium mines, the staff of other underground mines, such as workers in underground phosphate mines, can be exposed to 222 Rn and its progeny. In this study the individual radon progeny concentrations were measured in three Egyptian underground phosphate mines to estimate the occupational exposure of the workers at those sites. A filter method was used to measure individual radon progeny concentrations ( 218 Po, 214 Pb and 214 Po). The reported mean values of radon progeny concentrations exceed the action levels which are recommended by ICRP 65 (1993). Based on the measured individual radon progeny concentrations ( 218 Po, 214 Pb and 214 Po) in these mines, the annual effective dose for the workers has been calculated using the lung dose model of ICRP 66 (1994). According to the obtained results, some countermeasures were recommended in this study to minimise these exposure levels. (author)

  16. Exposure of workers to radon progeny in the Baradla cave at Aggtelek

    International Nuclear Information System (INIS)

    Dezsoe, Z.

    2004-01-01

    By measuring the radon concentration using active technique in all parts of the cave visited in a tour and furthermore by assessing also the time spent at these locations, it is possible to determine the radon level averaged over a tour. The time averaged radon concentration along the route of the cave investigated has been estimated to 970 Bq/m 3 in summer and 410 Bq/m 3 in winter. We concluded that in 62 % of the year cave climate shows warm season and only in 38 % cold season Rn-levels. On this basis the yearly mean radon concentration averaged over the tour comes to 750 Bq/m3. This figure, however, should not be used to estimate exposure because the number of visitors is substantially higher in summer than in winter, so that the tour guides work much more in summer (about 750 tours) than in winter (about 270 tours). Taking this into account, the yearly mean Rn concentration is to 820 Bq/m 3 . Since the dose is delivered by radon progeny and not radon itself, one has to also assess the equilibrium factor representative in the cave. The data available in the literature show that F is always larger than under normal ambient conditions. Published values are between 0.5 - 0.8. As part of this work, several radon progeny concentration measurements have also been made in the Baradla cave at different locations. The results confirm the occurrence of high F-values in caves. Furthermore, the equilibrium factor is increased by the presence of humans (visitors or cavers). In the Virgin Cave, F = 0.5 - 0.6, which increases steadily to about 0.8 due to the activity of man. In this work, F = 0.8 has been used for the dose assessment. Using the ICRP 65 dosimetry model, exposure was calculated to be 4.04 mJhm 3 , which corresponds to an effective dose of 5.8 mSv. (P.A.)

  17. Control of indoor radon and radon progeny concentrations

    International Nuclear Information System (INIS)

    Sextro, R.G.

    1985-05-01

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

  18. Dosimetry of inhaled radon and thoron progeny

    International Nuclear Information System (INIS)

    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 α 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 α dose from radon and thoron progeny, in order to obtain a realistic estimate of lung cancer risk

  19. 210Pb in bone in vivo - a biodosimeter for assessing uranium miner radon progeny exposure

    International Nuclear Information System (INIS)

    Guilmette, R.A.; Snipes, M.B.; Hoover, M.D.; Leggett, R.W.; Laurer, G.R.; Lambert, W.E.; Coons, T.A.; Gilliland, F.D.

    2002-01-01

    A joint analysis of the results of 11 epidemiological studies of lung cancer among uranium miners has shown a significant level of variability in the relative risk per unit of exposure - in the range of a factor of 30 (Lubin et al., 1994). A significant fraction of the uncertainty associated with these risk coefficients may be due to differences in the methods and quality of data used in calculating cumulative exposures, in WLM, for the various miner populations. We hypothesize that in vivo measurement of 210 Pb, a long-lived radon decay product that is retained in bone, will provide an improved measure of Rn progeny exposures received by individual miners during their mining careers. To accomplish such in vivo measurements, the lovelace in vivo bioassay facility (LIVBF) was modified to obtain an optimized counting geometry for measuring 210 Pb in the skull. Six 12.7 cm diameter phoswich detectors were positioned about the head of a reclining subject (one in the posterior, and one in the anterior position, and four about the mid-sagittal plane), and photon emission from the skull was measured using anticoincidence multichannel analysis electronics. We analyzed the in vivo data from about 90 former uranium miners from the grants mining district, and compared the recorded WLM exposures for each uranium miner (data from the UNM epidemiological data base) with a WLM exposure calculated using a model developed specifically for this study. This model couples a Pb biokinetic model with the ICRP publication 66 respiratory tract dosimetry model. The analyses show that the independent measurements of exposure are statistically correlated, but with a large degree of variability occurring among individual values, and that a major source of uncertainty in mining exposure estimation is the uncertainty involved in accounting for non-mining sources of 210 Pb. (orig.)

  20. Proceedings of radon and radon progeny measurements in Australia symposium

    International Nuclear Information System (INIS)

    Akber, R.A.; Harris, F.

    1994-01-01

    This publication contain papers presented at a symposium on radon and radon progeny measurements in Australia, held in Canberra on 18 February 1994. The emphasis was on results of measurements in different exposure situations, however information on methodology and techniques was also included. The scope of the symposium expanded through participation by scientists from China, French Polynesia and New Zealand. A list of participants and their organizations is included at the end of the proceedings. refs., tabs., figs

  1. Bronchial dosimeter for radon progeny

    Energy Technology Data Exchange (ETDEWEB)

    Cheung, T.K.; Yu, K.N.; Nikezic, D.; Haque, A.K.M.M. [City University of Hong Kong, Hong Kong (China); Vucic, D. [Faculty of Technology, University of Nis, Lescovac (Yugoslavia)

    2000-05-01

    Traditionally, assessments of the bronchial dose from radon progeny were carried out by measuring the unattached fraction (f{sub p}) of potential alpha energy concentration (PAEC), the total PAEC, activity median diameters (AMDs) and equilibrium factor, and then using dosimetric lung models. A breakthrough was proposed by Hopke et al. (1990) to use multiple metal wire screens to mimic the deposition properties of radon progeny in the nasal (N) and tracheobronchial (T-B) regions directly. In particular, they were successful in using four layers of 400-mesh wire screens with a face velocity of 12 cm s{sup -1} for the simulation of radon progeny deposition in the T-B region. Oberstedt and Vanmarcke (1995) carried out precise calibrations for the system, and named the system as the 'bronchial dosimeter'. Based on these, Yu and Guan (1998) proposed a portable bronchial dosimeter similar to a normal measurement system for radon progeny or PAEC and consisted of only a single sampler and employed only one 400-mesh wire screen and one filter. However, all these 'bronchial dosimeters' in fact only determined the fraction of potential alpha energy from radon progeny deposited in the T-B region, which required certain assumptions and calculations to further give the final bronchial dose. In the present work, a true 'bronchial dosimeter' was designed, which consisted of three 400-mesh wire screens and a filter. With a face velocity of 11 cm s{sup -1}, the deposition pattern on the wire screens was found to satisfactorily match the variation of the dose conversion factor (in the unit of mSv/WLM) with the size of radon progeny from 1 to 1000 nm. In this way, this bronchial dosimeter directly gave the bronchial dose from the alpha counts recorded on the wire-screens and the filter paper. With the development of this bronchial dosimeter, the present practice of 'dose estimation' from large-scale radon surveys can be replaced by large

  2. Interaction of radon progeny with atmospheric aerosols

    International Nuclear Information System (INIS)

    Morawska, Lidia

    1994-01-01

    The radiological health hazard due to the airborne radon progeny depends on three factors (i) radon concentration in the air, (ii) radon progeny concentration, and (iii) active particle size distribution. Conclusions as to the health hazard cannot be drawn without full understanding of the interaction mechanisms between radon progeny and atmospheric aerosols. The aim of this work was to study the interaction mechanisms between radon progeny, natural environmental aerosols and environmental tobacco smoke (ETS). The experiments were performed under controlled laboratory conditions of radon concentration (1.85 and 3.70 Bq m -3 ), relative humidity (35, 50, 75 and 95%) and ETS generation. The size distribution of radioactivity carrying aerosols was measured using a wire screen diffusion battery system and size distribution of all airborne aerosols using a differential mobility particle sizer. The paper presents and discusses the results of activity size distribution and radon progeny concentration measurements for different environmental conditions. 7 refs., 2 tabs

  3. Development of a portable radon progeny monitor

    International Nuclear Information System (INIS)

    Iimoto, Takeshi; Kosako, Toshiso; Sugiura, Nobuyuki

    2000-01-01

    Important nuclides in the radon family contributing to the effective dose are the members of the radon short-life progeny, 218 Po and 214 Po and direct measurement of these progenies is suitable for dosimetry. Survey of the radon progeny concentrations in a number of dwellings and offices is very difficult because we have no convenient instrument for the measurement. At present, radon dosimetry is carried out based on the concentration of the parent radon itself. Therefore, for accurate estimation of public or personal effective dose, it is necessary to develop a facile and portable radon progeny monitor. In this study, a portable radon progeny monitor (PRPM) was designed and developed to automatically estimate the individual progeny concentration in the natural environment. The properties of PRPM were investigated. The dimensions of the entire instrument were 65 x 145 x 170 mm and the total weight was 780 g. The portability of PRPM was much superior to the conventional instrument. The PRPM can operate automatically to estimate individual progeny concentration. All component materials of the monitor were selected based on the data of specified performance, cost performance and availability bon the market. The concentration of individual radon progeny was estimated by the build-up decay. It was concluded that PRPM is much suitable for outdoor study and personal dose estimation, as well as indoor measurement. In the field survey, especially in mines and caverns, PRPM is found as a valuable and convenient instrument. (M.N.)

  4. Dose assessment from exposure to radon, thoron and their progeny concentrations in the dwellings of sub-mountainous region of Jammu and Kashmir, India

    International Nuclear Information System (INIS)

    Kaur, M.; Dr. B. R. Ambedkar National Institute of Technology, Jalandhar, Punjab; Kumar, A.; Mehra, R.; Mishra, R.

    2018-01-01

    The present work deals with the assessment of annual inhalation dose due to exposure of indoor radon, thoron and their progeny concentrations in the villages situated in sub-mountainous region of Jammu and Kashmir, India. The distribution of the data and the homogeneity of medians among different seasons and dwellings were assessed with the Shapiro-Wilk test and the Mann-Whitney test. The estimated total annual inhalation dose in these villages varied from 0.5 to 1.9 mSv year -1 which is less than the prescribed limit by ICRP (2008). Thus, the investigated area is safe from irradiation of radon, thoron and their progeny. (author)

  5. Radon progeny exposure and lung cancer risk: Analyses of a cohort of Newfoundland fluorspar miners

    International Nuclear Information System (INIS)

    Morrison, H.I.; Villeneuve, P.J.

    1995-07-01

    A cohort study of the mortality experience (1950-1990) of 1744 underground miners and 321 millers or surface workers has been conducted. Excess mortality among underground miners was noted for cancers of the lung, buccal cavity, pharynx and mouth, urinary tract and for silicosis and pneumoconioses. A highly statistically significant relationship was noted between radon daughter exposure and risk of dying of lung cancer; the small numbers of buccal cavity/pharynx cancers (n = 6) precluded meaningful analysis of exposure-response. No statistically significant excess was found for any cause of death among surface workers. The exposure-response data for lung cancer were fitted to various mathematical models. The model selected included terms for attained age, cumulative dose, dose rate and time since last exposure. Because risk varies according to each of these factors, a single summary risk estimate was felt to be misleading. The joint effects of radon and smoking could not be adequately assessed using this cohort. (author). 46 refs., 16 tabs., 1 fig

  6. Attachment of radon progeny to cigarette-smoke aerosols

    International Nuclear Information System (INIS)

    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, ∼10 -6 cm 3 /s, occurred for the ambient aerosol. The sidestream and mainstream smoke aerosols exhibited higher attachment rates in that order. The results compared favorably with theories describing the coagulation process of aerosols

  7. Study of radiation exposure due to radon, thoron and progeny in the indoor environment of Yamuna and Tons valleys of Garhwal Himalaya

    International Nuclear Information System (INIS)

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

    2016-01-01

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

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

    Science.gov (United States)

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

    2016-10-01

    Long-term measurements of indoor radon, thoron and their progeny concentrations have been carried out in dwellings of Yamuna and Tons Valleys of Uttarkashi, Garhwal Himalaya to investigate the health risk associated with inhalation of radon, thoron and progeny. The experimentally determined values of radon, thoron and progeny concentrations were used to estimate the annual inhalation doses and annual effective doses. The annual inhalation dose has been found to vary from 0.8 to 3.9 mSv y -1 with an average of 1.8 mSv y -1 The annual effective dose from the exposure to radon and its progeny in the study area has been found to vary from 0.1 to 2.4 mSv with an average of 1.2±0.6 mSv. Similarly, the annual effective dose due to thoron and its progeny has been found to vary from 0.2 to 1.5 mSv with an average of 0.6±0.4. The measurement techniques and results obtained are discussed in detail. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. Control of radon and its progeny concentration in indoor atmosphere

    International Nuclear Information System (INIS)

    Ramachandran, T.V.; Subbaramu, M.C.

    1986-01-01

    Exposure to radon daughter concentration in indoor atmosphere can result in a significant risk to the general public. There are two generally used methods for the control of radon and progeny concentration in the indoor atmosphere, namely restriction of radon entry and reduction of indoor radon and its progeny concentration by ventilation or by air cleaning. Predominant radon entry process in most of the dwellings appears to be by pressure driven flow of soil gas through cracks or other openings in the basement slab or subfloors. Sealing these openings or ventilation of the subslab or subfloor space are the methods for reducing the radon entry rates. Indoor radon concentration can also be reduced by increasing the ventilation and by using charcoal filters for the removal of radon gas in indoor air by absorption. Concentration of radon progeny, which are responsible for most of the health risks associatd with radon exposure can also be controlled by the use of electrostatic or mechanical filters. This study describes briefly the above control strategies used for reducing the inhalation doses to persons in dwellings. (author). 9 refs., 2 tables

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

    International Nuclear Information System (INIS)

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

    1996-01-01

    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 -3 ). However, the radon concentrations-were low ( -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

  11. 220Radon (Thoron) and progeny exposures in the front-end of nuclear fuel cycle activities with special reference to radioactive minerals, thorium and rare earths processing

    International Nuclear Information System (INIS)

    Pillai, P.M.B.

    2008-01-01

    Radon is a major Source of radiation exposure both at home and work places due to its universal presence. The International Commission on Radiological Protection has always treated the radioactive noble gas radon ( 222 Rn) and its isotope thoron ( 220 Rn) as a separate subject. ICRP Publication 65 (ICRP, 1993) summarizes the current knowledge of health effects of inhaled radon and its decay products and gives recommendations/guidelines for the control of exposures due to high radon levels encountered in dwellings and work places. A major departure from earlier publications on the subject is the entirely epidemiological considerations for developing the recommendations. In work place monitoring the progeny concentrations are of primary concern than the gases themselves. However radon/thoron gas measurements may also be used provided reliable information on the equilibrium factors are available. Though many developments have taken place and many options are available for individual monitoring for radon (mainly progeny) exposures of occupational workers, a viable personal dosimeter for individual monitoring for thoron daughters is yet to materialize. The doses are mostly estimated by making use of work place monitoring data in combination with occupancy factors

  12. Measurements of thoron and radon progeny concentrations in Beijing, China

    International Nuclear Information System (INIS)

    Zhang Lei; Liu Cuihong; Guo Qiuju

    2008-01-01

    It has been reported that thoron levels in China are above the world average and may therefore make a significant contribution to the natural background radiation dose. We therefore conducted a pilot study of concentrations of both thoron and radon progeny during the spring of 2006 in the Beijing area, China. A new type of portable 24 h integrating monitor with a CR-39 detector was used during the survey. Seventy dwellings and eight outdoor sites were measured during the survey. For country houses built of red bricks and slurry, the average equilibrium equivalent concentrations (EEC) of thoron and radon were 1.02 ± 0.48 and 16.41 ± 9.02 Bq m -3 , respectively, whereas for city dwellings built of cement blocks and floor slabs, the results were 0.48 ± 0.47 and 11.50 ± 6.99 Bq m -3 for thoron and radon, respectively. For outdoor air, concentrations of thoron and radon progeny were 0.29 ± 0.28 and 7.05 ± 2.68 Bq m -3 , respectively. Radiation exposures from thoron and radon progeny were also evaluated; the ratio of dose contribution from thoron progeny to that of radon progeny was evaluated to be 28% and 17% in country houses and city dwellings, respectively. (note)

  13. AGE-DEPENDENT INHALATION DOSE DUE TO EXPOSURE OF SHORT LIVED PROGENY OF RADON AND THORON FOR DIFFERENT AGE GROUPS IN JAMMU & KASHMIR, HIMALAYAS.

    Science.gov (United States)

    Sharma, Sumit; Kumar, Ajay; Mehra, Rohit

    2018-05-16

    Dosimetric approach is used in this study for the assessment of doses due to inhalation of short lived radon/thoron progeny to the inhabitants of Udhampur district of Jammu & Kashmir. This paper also presents the activity concentrations and unattached fraction of radon and thoron progeny. The observed annual concentration of attached and unattached 222Rn and 220Rn progeny has been found to vary from 8 to 32 and 0.09 to 14 Bq/m3, 0.75 to 3.16 and 0.01 to 1.13 Bq/m3, respectively. The inhalation doses from radon progeny to different body organs of different age groups have been calculated by using the age dependent biokinetic model. The attachment rate of 222Rn and indoor aerosol concentration of 222Rn and 220Rn have been estimated and their relation between them has also been studied. The dose conversion factor for mouth and nasal breathing to different exposure conditions has been obtained from Porstendorfer model.

  14. Probing the application of Fourier Transform Infrared (FTIR) spectroscopy for assessment of deposited flux of Radon and Thoron progeny in high exposure conditions

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, R., E-mail: rosaline@barc.gov.in; Sapra, B.K.; Rout, R.P.; Prajith, R.

    2016-12-01

    Direct measurement of Radon and Thoron progeny in the atmosphere and occupational environments such as Uranium mines, Uranium and Thorium handling facilities has gained importance because of its radiological significance in inhalation dose assessment. In this regard, Radon and Thoron Progeny sensors (DTPS and DRPS) are the only passive solid state nuclear track detector (SSNTD, LR115) based devices which are being extensively used for time integrated direct progeny measurements. An essential component of the analysis is the chemical etching of the detectors, followed by spark counting of tracks and then estimation of the inhalation dose using appropriate calibration factors. Alternatively, the tracks may be counted using image analysis techniques. However, under high exposure conditions, both these methods have inherent limitations and errors arising due to increased frequency of tracks. In the present work, we probe the use of Fourier Transform Infra Red (FTIR) spectroscopy to analyse the deposited fluence of the progeny particulates based on change in transmittance of the nitric group vibrational bands of the LR115. A linear relationship between the transmittance and the deposited fluence was observed, which can be used to estimate the deposited fluence rate and the inhalation dose. This alternative method of analysis will provide a faster and non-destructive technique for inhalation dose assessment, specially for routine large scale measurements. - Highlights: • An alternative method of inhalation dose assessment. • Linearity between the transmittance of nitric goup bands and the deposited fluence. • Faster and non-destructive technique for high exposure scenarios.

  15. Microdosimetry of radon progeny: Application to risk assessment

    International Nuclear Information System (INIS)

    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

  16. Radon progeny mitigation using unipolar ion generators

    International Nuclear Information System (INIS)

    Sapra, B.K.; Arun Kumar; Khan, Arshad; Kothalkar, P.S.; Mayya, Y.S.

    2006-01-01

    Unipolar ion generators are often used for reduction of particulate levels in indoor environments. This paper explores the feasibility of their use in reducing radon progeny concentrations in a confined environment. Experiments have been carried out in a 10 m 3 test vessel in which ionizers are suspended in airspace and 226 Ra planchettes are placed as sources of radon. The radon, progeny and aerosol concentrations were estimated prior to and post-ioniser operation in the vessel using standard instruments and techniques. Results showed that the progeny concentrations decreased by a factor of about 10 with a mean life of about 35 min after ioniser was switched on. A mathematical model involving progeny, particle, ion space charge and electric field interaction processes been developed for estimating the various fractions of the progeny concentrations in the presence of the ionizer. The results of the model compared well with the experimental results. This study has a possible application for reducing progeny concentrations in U mines at local scales and specific working areas. (author)

  17. Measurements of size distributions of radon progeny for improved quantification of the lung cancer risk emanating from exposure to radon decay products; Messungen der Groessenverteilungen von Radon-Folgeprodukten zur Verbesserung der Quantifizierung des durch Radonexposition verursachten Lungenkrebsrisikos

    Energy Technology Data Exchange (ETDEWEB)

    Haninger, T

    1998-12-31

    A major issue in radiation protection is to protect the population from the harmful effects of exposure to radon and radon progeny. Quantification of the lung cancer risk emanating from exposure to radon decay products in residential and working environments poses problems, as epidemiologic studies yield information deviating from the results obtained by the indirect method of assessment based on dosimetric respiratory tract models. One important task of the publication here was to characterize the various exposure conditions and to quantify uncertainties that may result from application of the ``dose conversion convention``. A special aerosol spectrometer was therefore designed and built in order to measure the size distributions of the short-lived radon decay products in the range between 0.5 nm and 10 000 nm. The aerosol spectrometer consists of a three-step diffusion battery with wire nets, an 11-step BERNER impactor, and a detector system with twelve large-surface proportional detectors. From the measured size distributions, dose conversion coefficients, E/P{sup eq}, were calculated using the PC software RADEP; the RADEP program was developed by BIRCHALL and JAMES and is based on the respiratory tract model of the ICRP. The E/P{sup eq} coefficients indicate the effective dose E per unit exposure P{sup eq} to radon decay products. (orig./CB) [Deutsch] Eines der groessten Probleme des Strahlenschutzes ist der Schutz der Bevoelkerung vor einer Strahlenexposition durch Radon und seine Folgeprodukte. Die Quantifizierung des Lungenkrebsrisikos, das durch Radonexpositionen in Wohnungen und an Arbeitsplaetzen verursacht wird, ist ein grosses Problem, weil epidemiologische Studien ein anderes Ergebnis liefern, als die indirekte Methode der Abschaetzung mit dosimetrischen Atemtrakt-Modellen. Eine wichtige Aufgabe der vorliegenden Arbeit war es, unterschiedliche Expositionsbedingungen zu charakterisieren und die Unsicherheiten zu quantifizieren, die sich aus der

  18. Measurements of size distributions of radon progeny for improved quantification of the lung cancer risk emanating from exposure to radon decay products; Messungen der Groessenverteilungen von Radon-Folgeprodukten zur Verbesserung der Quantifizierung des durch Radonexposition verursachten Lungenkrebsrisikos

    Energy Technology Data Exchange (ETDEWEB)

    Haninger, T.

    1997-12-31

    A major issue in radiation protection is to protect the population from the harmful effects of exposure to radon and radon progeny. Quantification of the lung cancer risk emanating from exposure to radon decay products in residential and working environments poses problems, as epidemiologic studies yield information deviating from the results obtained by the indirect method of assessment based on dosimetric respiratory tract models. One important task of the publication here was to characterize the various exposure conditions and to quantify uncertainties that may result from application of the ``dose conversion convention``. A special aerosol spectrometer was therefore designed and built in order to measure the size distributions of the short-lived radon decay products in the range between 0.5 nm and 10 000 nm. The aerosol spectrometer consists of a three-step diffusion battery with wire nets, an 11-step BERNER impactor, and a detector system with twelve large-surface proportional detectors. From the measured size distributions, dose conversion coefficients, E/P{sup eq}, were calculated using the PC software RADEP; the RADEP program was developed by BIRCHALL and JAMES and is based on the respiratory tract model of the ICRP. The E/P{sup eq} coefficients indicate the effective dose E per unit exposure P{sup eq} to radon decay products. (orig./CB) [Deutsch] Eines der groessten Probleme des Strahlenschutzes ist der Schutz der Bevoelkerung vor einer Strahlenexposition durch Radon und seine Folgeprodukte. Die Quantifizierung des Lungenkrebsrisikos, das durch Radonexpositionen in Wohnungen und an Arbeitsplaetzen verursacht wird, ist ein grosses Problem, weil epidemiologische Studien ein anderes Ergebnis liefern, als die indirekte Methode der Abschaetzung mit dosimetrischen Atemtrakt-Modellen. Eine wichtige Aufgabe der vorliegenden Arbeit war es, unterschiedliche Expositionsbedingungen zu charakterisieren und die Unsicherheiten zu quantifizieren, die sich aus der

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

    International Nuclear Information System (INIS)

    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 ±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

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

    Science.gov (United States)

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

    2016-10-01

    In the present study, the measurements of indoor radon, thoron and their progeny concentrations have been carried out in the Rajpur region of Uttarakhand, Himalaya, India by using LR-115 solid-state nuclear track detector-based time-integrated techniques. The gas concentrations have been measured by single-entry pin-hole dosemeter technique, while for the progeny concentrations, deposition-based Direct Thoron and Radon Progeny Sensor technique has been used. The radiation doses due to the inhalation of radon, thoron and progeny have also been determined by using obtained concentrations of radon, thoron and their progeny in the study area. The average radon concentration varies from 75 to 123 Bq m -3 with an overall average of 89 Bq m -3 The average thoron concentration varies from 29 to 55 Bq m -3 with an overall average of 38 Bq m -3 The total annual effective dose received due to radon, thoron and their progeny varies from 2.4 to 4.1 mSv y -1 with an average of 2.9 mSv y -1 While the average equilibrium factor for radon and its progeny was found to be 0.39, for thoron and its progeny, it was 0.06. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Concentration ratio of radon progeny in air

    International Nuclear Information System (INIS)

    Kobayashi, Tsuneo

    2000-01-01

    Investigations have been made on the concentration ratio of radon progeny in air. Data have been acquired intermittently since 1988 using alpha spectroscopic method around the author's office that is located in the northeastern part of Japan. Clarifying the behavior of radon progeny is an issue of wide importance to radiation protection, predicting earthquakes, etc. Let Rabc=ECRn(RaA)/{ECRn(RaB) + ECRn(RaC)}; the concentration ratio, Rabc, is relevant to the stability of the air. Statistical and time series analyses indicated several interesting results. To examine the log-normal distribution, Lilliefors test was made for logarithm of outdoor data every one year. Rabc passed the test 6 times for 9 years, while Radon progeny passed 8 times. Outdoor data indicated that the value of Rabc was lower in the morning, in other world, the air was more stable in the morning than in the afternoon. To see the seasonal variation, one-way layout analysis was made for four groups of data, i.e., spring (March to May), summer (June to August), autumn (September to November), and winter (December to February). Rabc indicated significantly higher level in spring and winter, in other word, air was stable in summer and autumn. Time series analysis was made for various variables; power spectra were estimated with autoregressive model that is equivalent to maximum entropy method. Power spectrum for Rabc was most similar to that of wind speed. One-year period, that is always remarkable for radon progeny, was not significant for Rabc. Three- to nine-day periods were often seen for Rabc, radon progeny, wind speed, and atmospheric pressure. These several-day periods are probably attributed to the passage of air masses. Twenty-day to thirty-day peak may be attributed to meteorological phenomena corresponding to the rotation period of the sun. Temperature indicated no significant periodicity except overwhelming one-year period. Wind speed is well known to affect the radon progeny concentration

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

    International Nuclear Information System (INIS)

    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 -3

  3. Experimental determination of the absorption rate of unattached radon progeny from respiratory tract to blood

    International Nuclear Information System (INIS)

    Butterweck, G.; Schuler, Ch.; Vessl, G.; Mueller, R.; Marsh, J.W.; Thrift, S.; Birchall, A.

    2002-01-01

    An exposure methodology was developed for the determination of the absorption rate of unattached radon progeny deposited in the human respiratory tract to blood. Twenty-one volunteers were exposed in a radon chamber during well-controlled aerosol and radon progeny conditions, with predominantly unattached radon daughters. Special efforts were made to restrict the dose to the volunteers to an absolute maximum of 0.08 mSv. Measurements of radon gas and radon progeny in blood samples of these volunteers indicated absorption half times of 20 min to 60 min. Former determinations, mainly performed with much larger aerosol particles of diameters between 100 nm and 1000 nm, implied absorption half times around 10 h. This indicates that the absorption of radon decay products from ciliated airways into blood is dependent upon particle size and particle composition. (author)

  4. Study on radon and thoron progeny levels in Gudalore in South India

    International Nuclear Information System (INIS)

    Selvasekarapandian, S.; Sivakumar, R.; Mugunthamanikandan, N.; Meenakshisundaram, V.; Santhanam, R.

    2000-01-01

    One of the important route of radiation exposure to man is through inhalation of air containing radioisotopes. A major contribution to inhalation dose comes from radon, thoron and its progenies. The indoor radon and thoron progeny levels are determined by two count method. In this method the radon and thoron progenies are collected on a glass fiber filter paper using volume air sampler (Staplex) and counted for alpha activity in ZnS (Ag) alpha counting system. It is observed that thoron working level is higher than the radon working level in all houses except few houses with stone walls and mosaic floor. Behavior of indoor radon and thoron working levels for different seasons at different houses are determined and discussed in detail. Radon and thoron working levels are measured high in winter, autumn, and low in summer and rainy seasons. Among all seasons highest value is measured in winter and low in summer and rainy seasons. Radon progeny working level varies from 1.659 to 6.675 mWL, whereas thoron progeny working level varies from 1.670 to 12.671 mWL. The geometric mean values of radon and thoron progeny concentration in the present study are 2.836 and 4.133 mWL. The high thoron progeny level observed in this is attributed to the high thorium content observed in soils of this area. (author)

  5. Investigation of the exposure to radon and progeny in the thermal spas of Loutraki (Attica-Greece): Results from measurements and modelling

    International Nuclear Information System (INIS)

    Nikolopoulos, Dimitrios; Vogiannis, Efstratios; Petraki, Ermioni; Zisos, Athanasios; Louizi, Anna

    2010-01-01

    Radon and progeny ( 218 Po, 214 Pb, 214 Bi and 214 Po) in thermal spas are well known radioactive pollutants identified for additional radiation burden of patients due to the activity concentration peaks which appear during bath treatment or due to drinking of waters of high radon content. This burden affects additionally the working personnel of the spas. The present paper has focused on the thermal spas of Loutraki (Attica-Greece). The aim was the investigation of the health impact for patients and working personnel due to radon and progeny. Attention has been paid to radon and progeny transient concentration peaks (for bath treatment) and to radon of thermal waters (both for bath treatment and drinking therapy). Designed experiments have been carried out, which included radon and progeny activity concentration measurements in thermal waters and ambient air. Additionally, published models for description of radon and progeny transient concentration peaks were employed. The models were based on physicochemical processes involved and employed non linear first order derivative mass balance differential equations which were solved numerically with the aid of specially developed computer codes. The collected measurements were analysed incorporating these models. Results were checked via non linear statistical tests. Predictions and measurements were found in close agreement. Non linear parameters were estimated. The models were employed for dosimetric estimations of patients and working personnel. The effective doses of patients receiving bath treatment were found low but not negligible. The corresponding doses to patients receiving potable treatment were found high but below the proposed international limits. It was found that the working personnel are exposed to considerable effective doses, however well below the acceptable limits for workers. It was concluded that treatment and working in the Loutraki spas leads to intense variations of radon and progeny and

  6. Measurement of unattached radon progeny based in electrostatic deposition method

    International Nuclear Information System (INIS)

    Canoba, A.C.; Lopez, F.O.

    1999-01-01

    A method for the measurement of unattached radon progeny based on its electrostatic deposition onto wire screens, using only one pump, has been implemented and calibrated. The importance of being able of making use of this method is related with the special radiological significance that has the unattached fraction of the short-lived radon progeny. Because of this, the assessment of exposure could be directly related to dose with far greater accuracy than before. The advantages of this method are its simplicity, even with the tools needed for the sample collection, as well as the measurement instruments used. Also, the suitability of this method is enhanced by the fact that it can effectively be used with a simple measuring procedure such as the Kusnetz method. (author)

  7. Radon and thoron progeny measurements using a portable radon sniffer

    International Nuclear Information System (INIS)

    Efendi, Z.; Jennings, P.

    1993-01-01

    A flexible version of the two-count method has been developed for use in rapid, inexpensive measurements of radon and thoron progeny working levels in residential and industrial premises in the Perth Metropolitan Area. The Method is adapted for use with a simple radon sniffer based on a low speed pump and an alpha counter. The flexibility of the method derives from the software, where some freedom is permitted in the selection of sampling times and post sampling analysis of the filters. This method has been tested on a variety of radioactive materials and it gives consistent, reliable results over a wide range of working levels. The results of a survey of Rn(222) and Rn(220) progeny levels in dwellings within the Perth Metropolitan Area are reported. This study shows that the mean concentration of indoor Rn(222) progeny was 4.7 mWL (17.4 Bq m -3 EEC) up to 23.3 mWL (86.4 Bq m -3 EEC). The mean thoron progeny concentration was 8.2 mWL (2.25 Bq m -3 EEC) with a range from 1 mWL (0.27 Bq m -3 EEC) to 64.5 mWL (17.74 Bq m -3 EEC). Using conversion factors of 0.061 mSv Bq -1 m -3 for Rn(222) progeny and 0.29 mSv Bq -1 m -3 for Rn(220) progeny respectively (UNSCEAR, 1982), it is estimated the average annual effective dose equivalent is 1.1 mSv for Rn(2220 and 0.6 mSv for Rn(220) respectively. 22 refs., 4 tabs., 1 fig

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

    International Nuclear Information System (INIS)

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

    2015-01-01

    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 deg. 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. (authors)

  9. A radon progeny sampler for the determination of effective dose

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, S.B. [Australian Radiation Laboratory, Victoria (Australia)

    1997-12-01

    The design and simulated performance is described of a two-stage sampler (HE-Sampler) for {sup 222}Rn progeny. This HE-Sampler has a collection efficiency optimised to match the particle size dependency of the radon progeny dose conversion factor (DCF), derived from the latest Respiratory Tract Model of the International Commission on Radiological Protection, as implemented in the computer code RADEP. The He-Sampler comprises a wire screen pre-separator, matched to the nasal deposition, and a wire screen collector, matched to the respiratory tract collection. This HE-Sampler allows for the estimation of the radiation dose from the inhalation of {sup 222}Rn progeny, derived from two concurrent alpha particle activity measurements, one on the HE-Sampler screen collector and one on a reference filter sample. As a first approximation, the DCF is proportional to the collected fraction. The HE-Sampler response was simulated for a range of radon progeny size distributions to determine the error in the estimated DCF values. The simulation results show that the HE-Sampler is relatively insensitive to variations in sampling rate and in the screen parameters, particularly for environmental exposure. (Author).

  10. Lung Deposition And Biological Effects Of Inhaled Radon Progenies

    International Nuclear Information System (INIS)

    Balashazy, I.; Farkas, A.; Szoke, I.; Moustafa, M.; Kudela, G.

    2010-01-01

    Inhaled radon progenies provide more than the half of natural radiation exposure. There is increasing evidence that the cellular distribution of radiation burden is an important factor regarding the biological response to ionisation radiation, thus, one of our tasks was the characterisation of the distribution of cellular exposure. Histological studies of former uranium miners presented strong correlation between primer deposition hot spots and neoplastic lesions. Most of these lesions were located along the carinal regions of the large bronchial airways. In the present work, computational fluid dynamics (CFD) approaches have been applied to simulate the deposition distribution of inhaled radon progenies along central human airways. The geometry and the cellular structure of epithelial lung tissue were numerically reconstructed based on anatomical and histological data. Single and multiple ha-hit and cellular dose distributions have been computed applying Monte Carlo modelling techniques at different breathing conditions. Figure 1. Deposition enhancement factor (EF) of inhaled radon progenies on a central airway bifurcation in airway generations 4-5 during light physical activity breathing condition. Size of scanning surface element is a 45μm side triangle. Left panel: EF max=1400,Dp=200 nm (attached). Right panel: EF max1290, Dp= 1 nm (unattached). Values of local per average deposition densities, that is, enhancement factors (Figure 1), hit probabilities and doses may be up to two-three orders of magnitude higher in the deposition hot spots than the average values. Dose calculations revealed that some cell clusters may receive high doses even at low exposure conditions. Applying the model to different radiation exposure conditions useful relations can be received regarding the linear-non threshold hypothesis

  11. Plate-out rates of radon progeny and particles in a spherical chamber

    International Nuclear Information System (INIS)

    Cheng, Y.S.; Chen, B.T.

    1990-01-01

    In indoor and mining environments, deposition or ''plate-out'' of radon progeny onto walls occurs simultaneously with attachment of the radon progeny to airborne particles. Attachment and plate-out processes affect the atmosphere in which radon exposures takes place by reducing concentrations and shifting activity size distributions. Both processes have important consequences in determining the deposition pattern and initial dose of inhaled radon progeny. Theoretical deposition models show that turbulence and natural convection in a room are the major factors that influence plate-out rates. Here we describe plate-out measurements for radon progeny and aerosol particles in a spherical chamber under controlled laboratory conditions. The temperature and velocity profiles in still and turbulent air were monitored. A 161-liter spherical aluminum chamber was used to study the mixing. During mixing, air velocity was detected when rotational speeds were higher than 500 rpm. Monodisperse silver aerosols and polystyrene latex particles in the size range of 5 nm to 2 μm were used in the deposition study. Radon-220 progeny were generated by passing Rn-220 gas into the chamber and letting the gas decay into 212 Pb. The deposition rates of the particles and radon progeny ( 212 Pb) in the chamber were determined by monitoring the concentration decay of the aerosol as a function of time

  12. Cellular lung dosimetry for inhaled thoron progeny: comparison with radon progeny

    International Nuclear Information System (INIS)

    Abd El-Hady, M.; Hofmann, W.; Balashazy, I.

    1998-01-01

    Recently an analytical method was developed to compute radiation doses deposited by 222 Rn progeny alpha particles in 1 μm spheres located at different depths in bronchial epithelium. The same method was now applied to alpha particles emitted from 220 Rn progeny deposited in bronchial airway surfaces. Results of the computations are presented in graphs. The mean cellular doses imparted by 220 Rn progeny to basal and secretory cell nuclei were compared with those produced by 222 Rn progeny; due to differences in alpha energies, radon progeny doses were found to be generally higher than those for thoron progeny. (A.K.)

  13. Portable monitors for measuring radon and its progenies air by intergrated sampling method

    International Nuclear Information System (INIS)

    Zhang Huaiqin; Su Jingling; Yao Wanyuan; Liu Jinhua

    1989-01-01

    Two kinds of portable monitors have been developed, which can be used to measure the concentration of radon or potential energy concentration of radon or potential energy concentration of radon progenies in air. The thermoluminescent material CaSO 4 (Tm) is used as a detecting element for both of them. The lowest detectable limit of the passive radon monitor is about 1.5 Bq/m 3 for radon in air, as the exposure time being one week. Its main advantages are high reliability and convenient manipulation. The working level monitor for radon progenies in air consists of a mini membrane pump and an integrating probe. The lowest detectable limit is about 6.2 x 10 -9 J/m 3 , as the sampling time being 6 hours. It weights only about 0.35 kg

  14. Control methods of radon and its progeny concentration in indoor atmosphere

    International Nuclear Information System (INIS)

    Ramachandran, T.V.; Subba Ramu, M.C.

    1990-01-01

    Exposure to radon-222 and its progeny in indoor atmosphere can result in significant inhalation risk to the population particularly to those living in houses with much higher levels of Rn. There are three methods generally used for the control of Rn and its progeny concentration in the indoor environment: (1) restricting the radon entry, (2) reduction of indoor radon concentration by ventilation or by aircleaning and (3) removal of airborne radon progeny by aerosol reduction. Prominent process of radon entry in most of the residence appears to be the pressure driven flow of soil gas through cracks or through other openings in the basements slab or subfloor. Sealing off these openings or ventilation of the slab or subfloor spaces are the methods of reducing the radon entry rate. Indoor radon progeny levels can also be reduced by decreasing the aerosol load in the dwellings. The results of a few experiments carried out to study the reduction in the working level concentration of radon, by decreasing the aerosol load are discussed in this paper. (author). 9 tabs., 8 figs., 37 refs

  15. Changes in the rat lung after exposure to radon and its progeny: Effects on incorporation of bromodeoxyuridine in epithelial cells and on the incidence of nuclear aberrations in Alveolar macrophages

    International Nuclear Information System (INIS)

    Taya, A.; Morgan, A.; Baker, S.T.; Humphreys, J.A.H.; Collier, C.G.; Bisson, M.

    1994-01-01

    The aim of this study was to investigate some responses of cells in the rat respiratory tract as a function of time after inhalation exposure to various levels of radon and its progeny. Rats were exposed to a constant concentration of radon and its progeny to give cumulative exposure levels of 120, 225, 440 and 990 working level months (WLM). An additional unexposed group of rats served as controls. The end points selected for investigation were (a) the incorporation of bromodeoxyuridine (BrdU) in epithelial cells of the conducting airways and of the alveolar region of the respiratory tract and (b) the incidence of alveolar macrophages with nuclear aberrations. After exposure, the incidence of epithelial cells incorporating BrdU-the labeling index-increased in all regions of the respiratory tract examined, but the increase occurred later in alveolar than in airway epithelial cells. The highest labeling index was found in bronchial epithelial cells, which probably received the highest radiation dose. After an initial induction period, the incidence of alveolar macrophages with nuclear aberrations also increased. The possibility of using the labeling index of alveolar and airway epithelial cells, and/or the incidence of nuclear aberrations in alveolar macrophages, to estimate the radiation dose to various regions of the respiratory tract after exposure of rats to radon and its progeny is discussed. 22 refs., 3 figs., 1 tab

  16. Radiological impact of exposure to radon-thoron and their progeny present in the environment of fly ash dumping site in Faridabad (Haryana)

    International Nuclear Information System (INIS)

    Gupta, Nitin; Kant, Krishan; Garg, Maneesha

    2013-01-01

    Radon-Thoron and their Progeny monitoring was carried out in dwellings near fly ash dumping sites in Faridabad (Haryana), as it is very important from health and hygiene point of view of the occupants. For the measurements, the track etch technique was used. The dosimeter employed for the measurement consisted of twin chamber systems with LR-115 Type II SSNTDs placed on the two sides of the central partition inside the cup and a bare film placed outside it. The detectors were exposed in the mixed field of radon-thoron in the environment of dwellings. The detectors were placed in about 100 dwellings and the choice of the dwelling was random. The value of PAEC, radon concentration, annual exposure, annual effective dose in the dwellings near fly ash dumping sites in District Faridabad (Haryana) varied from 1.34 mWL to 14.05 mWL with an average value of (4.95 0.85) mWL, 12.41 Bqm -3 to 129.91 Bqm -3 with an average value of (45.77 7.87) Bqm -3 , 0.55 10 -1 WLM to 5.83 10 -1 WLM with an average value of (2.04 0.28) 10 -1 WLM and 0.21 mSv to 2.23 mSv with an average value of (0.79 0.13) mSv. The value of PAEC, thoron concentration, annual exposure, annual effective dose in the dwellings near fly ash dumping sites in District Faridabad (Haryana) varied from 1.34 mWL to 14.0 SmWL with an average value of (4.95 0.85) mWL, 1.16 Bq/m 3 to 65.08 Bq/m 3 with an average value of (32.77 7.87) Bqm -3 , 0.55 10 -1 WLM to 5.83 10 -1 WLM with an average value of (2.04 0.28) 10 -1 WLM and 0.21 mSv to 2.23 mSv with an average value of (0.79 0.13) mSv. The measurements indicate that the radon concentration was below the safety levels (action levels) as recommended by various regulatory bodies. The maximum value of 129.91 Bqm -3 was found in a cave inside a temple, where there was no ventilation. The different values of radon concentrations are due to different ventilation conditions and house structures. The radon concentration was found to decrease with the increase in distance of the

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  19. Indoor thoron and radon progeny measurements

    International Nuclear Information System (INIS)

    Tu, K.W.; George, A.C.; Lowder, W.M.; Gogolak, C.V.

    1992-01-01

    Measurements of indoor thoron ( 220 Rn) and radon ( 222 Rn) progeny activities were conducted in 40 homes and six public buildings in five states. A commercial alpha spectrometer system and four portable alpha integrating sampling monitors using diffused junction silicon detectors were used for sampling and recording of radionuclide data in particular the potential alpha energy concentrations (PAEC). The data were analysed for the ratios of PAEC- 220 Rn to PAEC- 222 Rn, and the correlations between the two quantities, and their estimated annual effective dose equivalent (AEDE). The results show that the PAEC ratios were 0.09, 0.6, 0.55, and 0.47, respectively, for all homes with the PAEC- 222 Rn > 400, between 100 and 400, -3 , and the total of all homes tested; the AEDE ratios were 0.03, 0.21, 0.19 and 0.16, respectively. No strong correlations were found between PAEC- 220 Rn and PAEC- 222 Rn, and between basement and ground floor data for PAEC- 220 Rn, but the PAEC- 222 Rn data showed a strong correlation between the basement and the ground floor values. Simultaneous measurements of PAEC- 220 Rn and PAEC- 222 Rn on the ground floor and in the basement of each of the 23 single-family houses tested suggests that 220 Rn entry from building materials may be as significant as from the underlying soil. (author)

  20. Radon Progeny In Underground Phosphate Mines and Their Activity Distributions In Human Lung

    International Nuclear Information System (INIS)

    Abd El-Hady, M.; Mohammed, A.; El-Hussein, A.; Ali, A.E.; Ahmed, A.A.

    2001-01-01

    In addition to workers in uranium mines, the staff of other underground mines, such as worker in underground phosphate mines, Can be exposed to 222 Rn and its progeny. In this study the individual radon progeny concentrations were measured in three Egyptian underground phosphate mines to estimate the occupational exposure to the workers in those sites. Active techniques are employed to fulfill the objective of measuring individual radon progeny concentrations (C RaA , C RaB and C RaC ). The mean reported values of radon progeny concentrations exceed the action levels recommended by ICRP 65 (1993). Based on the physical properties of attached radon progeny aerosol and physiological parameters for heavy work activity which recommended by ICRP 66 (1994). the deposition fraction for each airway generation was calculated. From the measured individual radon progeny concentrations in these mines and the calculated values of deposition fractions, the surface activity distribution per generation were calculated in human respiratory system (BB and regions). The maximum values of these activities were found in the upper bronchial airway generations. According to the obtained results, some of the corrective actions were recommended in this study

  1. Measurement of radon and thoron progenies in Coimbatore

    International Nuclear Information System (INIS)

    Sivakumar, R.; Selvasekarapandian, S.; Mahendraprasad, M.; Meenakshisundaram, V.; Santhanam, R.; Raghunath, V.M.

    2001-01-01

    The radon and thoron daughter concentrations have been measured in different dwellings of Coimbatore city by grab sampling method and two count. It has been found that the radon daughter concentration varies from 0.5 to 10.5 mWL with mean value of 2.9 mWL and that of thoron progeny is from 0.7 to 16.3 mWL with mean value of 3.8 mWL. The average annual effective dose equivalent due to radon daughters is found to be 1.3 mSv and that of thoron progeny is 3.8 mSv. (author)

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

    International Nuclear Information System (INIS)

    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 -3 222 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 ± 0.08. Eighty-five percent of all the radon measuring devices that were exposed in the EML radon test chamber were within ±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 ± 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 -3 ). The equilibrium factor at that particle concentration level was 0.10--0.22

  3. The use of track registration detectors to reconstruct contemporary and historical airborne radon ( sup 2 sup 2 sup 2 Rn) and radon progeny concentrations for a radon-lung cancer epidemiologic study

    CERN Document Server

    Steck, D J

    1999-01-01

    Epidemiologic studies that investigate the relationship between radon and lung cancer require accurate estimates for the long-term average concentrations of radon progeny in dwellings. Year-to-year and home-to-home variations of radon in domestic environments pose serious difficulties for reconstructing an individual's long-term radon-related exposure. The use of contemporary radon gas concentrations as a surrogate for radon-related dose introduces additional uncertainty in dose assessment. Studies of glass exposed in radon chambers and in a home show that radon progeny deposited on, and implanted in, glass hold promise for reconstructing past radon concentrations in a variety of atmospheres. We developed an inexpensive track registration detector for the Iowa Radon Lung Cancer Study (IRLCS) that simultaneously measures contemporary airborne radon concentrations, surface deposited alpha activity density, and implanted sup 2 sup 1 sup 0 Po activity density. The implanted activity is used to reconstruct the cum...

  4. Lung dosimetry for inhaled radon progeny

    International Nuclear Information System (INIS)

    Hofmann, W.

    1986-01-01

    Lung cancer risk assessment for inhaled radon progeny requires a detailed knowledge of the dose distribution pattern throughout the human respiratory tract. Current lung dosimetry models take into acocunt aerosol deposition in a formalized airway structrue, modification of the initial deposition pattern by clearance mechanisms, and the energy deposited by alpha particles in sensitive cells of the bronchial epithelium. The resulting dose distribution pattern depends on the characteristics of the inhaled aerosol and the breathing pattern. Special emphasis has been laid on the age dependency of the anatomical structure of the human lung and the resulting doses, as well as on the rediological significance of enhanced aerosol deposition at bronchial bifuraction. The biological variability inherent in all morphometric, physiological and histological parameters involved in lung dosimetry suggests the application of stochastic modelling techniques. Examples for the use of Monte Carlo methods presented here are the random walk of inhaled particles through a random airway geometry, and the influence of the intra-subject variability of radiation doses on radiation protection standards. At the cellular level the concept of absorbed dose loses its significance and has to be replaced by microdosimetric concepts, such as internal microdosimtry or track structure theory. An image-analysis model allows us to construct specific energy distributions in sensitive lung cells. Application of a track structure model of alpha particle interaction with bronchial epithelial cells permits the calculation of probabilities for inactivation, transformation, and tumor induction. The latter has been used to analyse lung cancer risk at low doses in Chinese high background areas

  5. Deposition of radon progeny in nonhuman primate nasal airways

    International Nuclear Information System (INIS)

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

    1992-01-01

    Radon progeny are usually associated with ultrafine particles ranging in diameter from 0.001 to 0.005 μm for open-quotes unattachedclose quotes progeny and from 0.005 to 0.2 μm 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 μm in the nasal passages of laboratory animals is available; however, there is little information on the deposition of particles smaller than 0.2 μm. In this report, we describe the use of nasal casts of a rhesus monkey to measure total deposition of ultrafine aerosols, including unattached 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 μm, 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 22- Rn progeny, at particle sizes from 0.001 to 0.003 μm. 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 b Q c ) for d p ≤ 0.2 μm, was derived, where E is the deposition efficiency, d 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

  6. Prediction of lung cells oncogenic transformation for induced radon progeny alpha particles using sugarscape cellular automata.

    Science.gov (United States)

    Baradaran, Samaneh; Maleknasr, Niaz; Setayeshi, Saeed; Akbari, Mohammad Esmaeil

    2014-01-01

    Alpha particle irradiation from radon progeny is one of the major natural sources of effective dose in the public population. Oncogenic transformation is a biological effectiveness of radon progeny alpha particle hits. The biological effects which has caused by exposure to radon, were the main result of a complex series of physical, chemical, biological and physiological interactions. The cellular and molecular mechanisms for radon-induced carcinogenesis have not been clear yet. Various biological models, including cultured cells and animals, have been found useful for studying the carcinogenesis effects of radon progeny alpha particles. In this paper, sugars cape cellular automata have been presented for computational study of complex biological effect of radon progeny alpha particles in lung bronchial airways. The model has included mechanism of DNA damage, which has been induced alpha particles hits, and then formation of transformation in the lung cells. Biomarkers were an objective measure or evaluation of normal or abnormal biological processes. In the model, the metabolism rate of infected cell has been induced alpha particles traversals, as a biomarker, has been followed to reach oncogenic transformation. The model results have successfully validated in comparison with "in vitro oncogenic transformation data" for C3H 10T1/2 cells. This model has provided an opportunity to study the cellular and molecular changes, at the various stages in radiation carcinogenesis, involving human cells. It has become well known that simulation could be used to investigate complex biomedical systems, in situations where traditional methodologies were difficult or too costly to employ.

  7. Radon progeny distribution in cylindrical diffusion chambers

    International Nuclear Information System (INIS)

    Pressyanov, Dobromir S.

    2008-01-01

    An algorithm to model the diffusion of radioactive decay chain atoms is presented. Exact mathematical solutions in cylindrical geometry are given. They are used to obtain expressions for the concentrations of 222 Rn progeny atoms in the volume and deposited on the wall surface in cylindrical diffusion chambers. The dependence of volume fractions of 222 Rn progeny and chamber sensitivity on the coefficient of diffusion of 222 Rn progeny atoms in air is modeled.

  8. Radon and thoron progeny levels in air samples at Udagamandalam region of Nilgiris in India

    International Nuclear Information System (INIS)

    Manikandan, N.M.; Selvasekarapandian, S.; Sivakumar, R.; Raghunath, V.M.; Sundaram, V.M.; Santhanam, S.

    2002-01-01

    Measurement of concentration of radon and thoron daughter products in various indoor environment covering four seasons of a year in Udagamandalam Taluk of Nilgiris biosphere has been carried out using a high volume air sampler to assess the inhalation dose to the population which delivers higher dose than the radon and thoron gas alone. The potential alpha-energy concentrations of the radon and thoron progeny ranged from 0.97 to 12.72 mWL and from 1.63 to 15.83 mWL with a geometric mean of 6.02 and 7.89 mWL, respectively, taking all seasons into account. These measurements have yielded a wealth of data on the variation among the indoor radon and thoron progeny in various places during different seasons. The radon and thoron progeny levels are higher in winter seasons and are less in summer season with autumn and spring data lie in between winter and summer. Using the dose conversion factor for indoor exposures given in UNSCEAR 93 report the internal equivalent dose to the inhalation of radon progeny is evaluated to be 1357 μSv x y -1 and the corresponding annual effective dose equivalent value has been found to be 2.13 mSv x y -1 . It can be observed that the mean value of radon is higher than the Indian average. Also it is found the radon and thoron progeny levels are higher in the case of houses built with rock and granite and in tiled type houses of nearly 100 years old. The levels are less in the case of houses built with brick and cement. The observed results for different types of houses and seasons are discussed in this paper. (author)

  9. Distribution characteristics of radon and its progeny in blind roadway with forced ventilation

    International Nuclear Information System (INIS)

    Ye Yongjun; Zhou Xinghuo; Li Xiangyang; Zhong Yongming; Liu Dong; Ding Dexin

    2012-01-01

    The blind roadway is not only the important workplaces, but also is important site of radon and its progeny generating and gathering, it is an important guiding significance for ventilation protection design to study distribution characteristics of radon and its progeny in blind roadway. Therefore, at first, the paper expounded the mathematical relationship between radon activity concentration with alpha potential concentration of radon progeny. Then, analyzed the sources of radon and its progeny, and established mathematical calculation model of Distribution characteristics of radon and its progeny in blind roadway with forced ventilation, respectively. Finally, using mathematical calculation models to analyze the influence law of multiple factors. (authors)

  10. Unattached fraction of radon progeny in Polish coal mines

    International Nuclear Information System (INIS)

    Skubacz, K.; Michalik, B.

    2002-01-01

    The system of the monitoring of the radiation hazard in Polish coal mines is based on the monitoring of the workplaces. This system works since 1989 in all coal mines. It gives a very good basis for further epidemiological investigation and assessment of the health detriment within the population of the mines as a result of the exposure for natural radiation. It is very important problem, due to the fact of the presence in the mines another factors, which probably have a synergetic effects on the respiratory tracts. As the routine instrument, a device called ALFA-31 sampling probe was developed in our laboratory. This device was accomplished to regular dust sampler and simultaneous measurements of dust content and potential alpha energy concentration of radon progeny are obligatory in all underground mines in Poland. But the microcyclone used a separator of the respirable fraction which causes the cut-off of unattached fraction of radon progeny, On the other hand measurements of the unattached fraction of short lived radon progeny play a very important role in the investigations of the adequate dose from this source of radiation hazard. During field experiments the use of the alpha spectroscopy system is necessary, while measurements are done not in the vacuum chambers but under normal pressure. It leads to situation, when particular peaks in alpha spectrum are very wide and interfere with other peaks of another alpha-emitting radionuclides. Such instrumentation was designed and completed, and a survey in several underground mines was performed. The analysis of the obtained results must be done very carefully; in other case it may cause a very big uncertainty of the result. In this paper a new approach to the analysis of the alpha spectra has been described. This approach can be used also in other applications of alpha spectroscopy, in which the analysis of energy of alpha peaks in spectrum is needed. The method of the analysis is based on a non-linear regression

  11. Diurnal variations of indoor radon progeny for Bangalore metropolitan, India

    International Nuclear Information System (INIS)

    Nagesh, V.; Sathish, L.A.; Nagaraja, K.; Sundareshan, S.

    2010-01-01

    Radon progenies are identified as major causes of the lung cancer if the activity is above its normal. It has not been clear whether radon poses a similar risk of causing lung cancer in humans exposed at generally lower levels found in homes, but a number of indoor radon survey have been carried out in recent years around the world. In view of this an attempt has been made for the measurement of diurnal variation of indoor radon levels for the environment of Bangalore metropolitan, India. The Radon progeny concentrations in terms of working level were measured using Kusnetz's method. The patterns of daily and annual changes in indoor Radon concentration have been observed in a general way for many years. However, understanding of the physical basis for these changes had to await the development of continuous monitors and a more complete knowledge of transport processes in the atmosphere. Over a continent, heating of the ground surface by the Sun during the day and cooling by radiation during the night causes a marked diurnal change in temperature near the surface. As a result cool air near the ground will accumulate radon isotopes from surface flux during the night; while during the day the warm air will be transported upward carrying radon with it. Many buildings show diurnal radon variations. Concentrations are relatively higher during night than daytime. This is influenced by the outdoor-indoor temperature contrast. This effect can be enhanced in buildings with strong diurnal use patterns. Buildings that have high average radon concentrations, but are only occupied for part of the day, may need to be measured during occupied periods to determine if there is significant diurnal radon variation. The results are discussed in detail. (author)

  12. Field investigation of surface-deposited radon progeny as a possible predictor of the airborne radon progeny dose rate.

    Science.gov (United States)

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

    2009-08-01

    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 fireplace, or usage of a ceiling fan significantly, or marginally 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 radon progeny effects and other environmental factors, for every 10 additional cigarettes smoked in the room. A significant increase of 1.71 in the mean Pdose was found for large room size relative to small room size (90% CI 1.08-2.79) after adjusting for the radon and radon progeny effects as well as other environmental factors. Fireplace usage was found to significantly increase the mean Pdose to 1.71 (90% CI 1.20-2.45) after adjusting for other factors.

  13. Cellular dosimetry for radon progeny alpha particles in bronchial tissue

    International Nuclear Information System (INIS)

    Mohamed, A.; Hofmann, W.; Balashazy, I.

    1996-01-01

    Inhaled radon progeny are deposited in different regions of the human bronchial tree as functions of particle size and flow rate. Following deposition and mucociliary clearance, the sensitive bronchial basal and secretory cells are irradiated by two different alpha particle sources: (i) radon progeny in the sol and/or gel phase of the mucous layer, and (ii) radon progeny within the bronchial epithelium. In the case of internally deposited radionuclides, direct measurement of the energy absorbed from the ionizing radiation emitted by the decaying radionuclides is rarely, if ever, possible. Therefore, one must rely on dosimetric models to obtain estimates of the spatial and temporal patterns of energy deposition in tissues and organs of the body. When the radionuclide is uniformly distributed throughout the volume of a tissue of homogeneous composition and when the size of the tissue is large compared to the range of the particulate emissions of the radionuclide, then the dose rate within the tissue is also uniform and the calculation of absorbed dose can proceed without complication. However, if non-uniformities in the spatial and temporal distributions of the radionuclide are coupled with heterogeneous tissue composition, then the calculation of absorbed dose becomes complex and uncertain. Such is the case with the dosimetry of inhaled radon and radon progeny in the respiratory tract. There are increasing demands to obtain a definitive explanation of the role of alpha particles emitted from radon daughters in the induction of lung cancer. Various authors have attempted to evaluate the dose to the bronchial region of the respiratory tract due to the inhalation of radon daughters

  14. Concentration of Radon Progeny in Air by Alpha Spectrometry Measurement

    International Nuclear Information System (INIS)

    Acena, M. L.; Crespo, M. T.

    1989-01-01

    The concentration of radon progeny in air has been determined by alpha spectrometry measurement of 214 Po and 318 Po. A known volume of air was passed through a filter, then the alpha activity was directly measured on this filter. (Author) 15 refs

  15. Developmental toxicology of radon exposures

    International Nuclear Information System (INIS)

    Sikov, M.R.; Cross, F.T.; Mast, T.J.; Palmer, H.E.; James, A.C.; Thrall, K.D.

    1992-01-01

    Concerns about hazards associated with radon exposure in dwellings may be especially relevant to pregnant women, many of whom spend substantial amounts of time in their homes. There are few data concerning the placental transfer and fetoplacental distribution of inhaled radon and decay products or their effects on the conceptus. We performed a study in rats to determine if prenatal effects could be produced by prolonged inhalation exposures to high concentrations of radon throughout gestation. A group of 43 pregnant rats was exposed 18 h d -1 , at a rate of 124 working level months (WLM) per day, from 6 to 19 days of gestation (dg), of radon and daughters adsorbed onto ore dust. A group of 26 pregnant rats from the same shipment was exposed to a filtered-air atmosphere as controls. At 20 dg, the rats were removed from the chambers, killed, and necropsied. The fetuses were evaluated for the presence of toxic effects, which included detailed teratology protocols. These exposures did not produce detectable reproductive toxicity nor teratogenic change. Two other rats were removed from the radon chambers during the last day of exposure, and their tissues were analyzed to determine the distribution of radioactivity and for dosimetry. Samples from these rats suggested that the dose rates to the placenta were roughly threefold those to the fetus but were similar to those to the liver and femur of the pregnant rats. These data indicate that the dose to the conceptus from the decay of placentally transferred radon and its progeny is more important than the contribution of translocated decay products. Translocated radon decay products are an important source of radiation doses to placental structures, however, and may have most of the radioactivity content at birth

  16. Studies of Radon and Radon Progeny in Air Conditioned Rooms in Hospitals

    International Nuclear Information System (INIS)

    Marley, F.; Denman, A.R.; Phillips, P.S.

    1998-01-01

    A series of continuous real-time radon and radon progeny measurements together with passive etched track detector measurements were performed in hospital premises during 1996. In one small room, detailed measurements over several weeks showed that both the radon concentration and the Equilibrium Factor depended on the intermittent operation of a filtered positive pressure displacement air-conditioning system, which was designed to conform to operating theatre standards. The average radon level measured while the air-conditioning was off was almost four times higher than that recorded whilst it was on. The progeny level was over five times higher than that whilst it was on. Thus, the Equilibrium Factor (F), was significantly lower when the air-conditioning was on. Measurements in similar rooms in two hospitals, confirmed that the reduction in radon level was a general finding. Thus staff working in such environments receive significantly lower radiation dose from radon than staff working in nearby normally ventilated rooms. (author)

  17. Environmental Concentration of Radon and Radon Progeny in a Nuclear Facility in a Decommissioning Stage

    International Nuclear Information System (INIS)

    Ramirez, M. P.; Correa, E.; Sancho, C.

    1999-01-01

    According to the new European Directive 96/29/EURATOM the radiological risk due to natural radionuclides must be consider and the pertinent periodic control must be realized. During the works performed at CIEMAT an estimation of the effective average doses due to Radon inhalation in work places of the installation have been performed. Radon and Radon progeny concentration has been measured in continuous joint whit the meteorological conditions as temperature, pressure and relative humidity. Two different equipment has been used: Alpha-guard whit ionization chamber detector and Eda-wlm-300 whit a semiconductor detector. A passive Radon detector, E-perm has been simultaneously used in the monitoring system. The results obtained during the measuring of Radon and Radon progeny concentrations indoors and estimation of doses have been analyzed and are presented in the paper. (Author) 11 refs

  18. Microclimatic effects on outdoor radon and its progeny in a long-term study

    International Nuclear Information System (INIS)

    Schuetz, M.; Keller, G.; Kappel, R.J.A.

    1994-01-01

    The dose due to the long term radon exposure is estimated from the radon concentration and from an equilibrium factor that in the literature is reported with a wide uncertainty. Therefore the radon equilibrium factor outdoors and its dependence on climatic effects should be investigated in a long-term study. Both the outdoor concentrations of radon and of its progeny near Ellweiler/Hunsrueck were measured continuously during 12 months and the resulting equilibrium factors were determined. Simultaneously to the every 2 hour's radon data many meterological parameters as temperature and relative to humidity of the air, barometric pressure and duration and amount of rainfall were recorded. At a height of 6 meters above ground and in 10 minute intervals the local wind direction and velocity were registered. By that a set of more than 3000 single measurements of the equilibrium factor and of the corresponding weather conditions was collected

  19. Utilisation of an Air-conditioning System to Control the Levels of Radon and Radon Progeny in a Workplace Environment

    International Nuclear Information System (INIS)

    Marley, F.

    2000-01-01

    From long-term real-time radon and radon progeny measurements taken in a relatively large retail store, cyclical patterns were evident, which were found to relate to the overriding influence of the timed air-conditioning system. Concentration of radon, radon progeny and the variability of F factor were found to depend significantly on the intermittent operation of this ventilation-air-conditioning system. After pressure equalisation remedial measures proved ineffective, the air-movement system was utilised to reduce the levels of radon and radon progeny to well within established norms applicable during working hours. It is demonstrated that the average levels for radon and radon progeny are reduced in absolute terms. This amounted to less than 12% of the general level, during designated work periods. Where air movement systems are already installed, as well as other circumstances, their regulation provides an economical solution to meeting legal and other standards for radon in the workplace. (author)

  20. Measurement of radon and thoron progeny size distributions and dose assessments at the mineral treatment industry in Thailand

    International Nuclear Information System (INIS)

    Chutima Kranrod; Supitcha Chanyotha; Nares Chankow

    2013-01-01

    A new portable type cascade impactor has been developed to determine the activity size distribution of radon and thoron progeny in a natural environment more efficiently. The modified impactor consists of 4 stages with a back up filter stage for the collection of aerosol samples. The aerosol cut points in the impactor are set for 10, 2.5, 1 and 0.5 μm at a flow rate of 4 L min -1 . Five CR-39 chips were used as alpha detectors for each stage. In order to separate α particles emitted from radon and thoron progeny, CR-39 detectors are covered with aluminum-vaporized Mylar films. The thickness of each film is adjusted to allow α particles emitted from radon and thoron progeny to reach the CR-39 detectors. The technique has been successfully tested in field studies, particularly inside a mineral treatment industry in Thailand to estimate doses in the working environment. The dose calculations by lung dose evaluation program showed that activity median aerodynamic diameters played a significant role in determining the particle size distributions of the attached radon and thoron progeny. The dose conversion factor determined from short term measurements due to exposure from the inhalation of thoron and its progeny was found to be 4 times higher than comparable values for radon and its progeny. The effective dose for workers exposed to radon is about 4-6 times higher than thoron. (author)

  1. Determination of radon and progeny concentrations in Brazilian underground mines

    International Nuclear Information System (INIS)

    Fraenkel, Mario O.; Gouvea, Vandir de Azevedo; Macacini, Jose F.; Cardozo, Katia; Carvalho Filho, Carlos A. de; Lima, Carlos E.

    2008-01-01

    The aim of this work is to present the activities related to the determination of radon and progeny concentrations in underground mines in Brazil. Radon is originated from decay of radium-226 and radium-228 present in rocks. Radon and its short-lived progeny can be retained in the workers pulmonary alveoli, and this way they bring about cancer risk to these mining professionals. The occurrence of high radon concentrations in underground coal and copper mines and the lack of systematic survey motivated CNEN, the regulatory agency, to develop the Radon Project, aiming to aid the formulation of a specific regulation with occupational dose limits consistent with international standards recommended by the International Atomic Energy Agency (IAEA). Dozens of underground mines are currently in operation in the national. It had to be noted that about 50% of these mines are located in Minas Gerais province, and for this reason it was chosen to start the Project. In each underground mine it is installed in selected points passive nuclear track etch radon detectors, type LEXAN and Cr-39, for periods from three to five months. It was also made local measurements with Dose Man Pro detectors from SARAD. The points are chosen according to geological features, radiometric activity and characteristics of prospect development. The determination of radon present in mines has been made in IEN (Nuclear Engineering Institute)/Rio de Janeiro-RJ, LAPOC (Pocos de Caldas Laboratory)/Pocos de Caldas-MG e ESPOA (Porto Alegre Office)/Porto Alegre-RS. Until now it was visited about 35 mines in a universe of about 50 mines, from which 20% showed concentration values higher than international limits (ICRP 65), between 500 and 1500 Bq.m -3 . (author)

  2. Radon, thoron and their progeny levels in some dwellings of Union Territory Chandigarh, India using SSNTDs

    International Nuclear Information System (INIS)

    Mehta, Vimal; Kumar, Amit; Chauhan, R.P.; Mudahar, G.S.

    2013-01-01

    Indoor air quality is an important issue for protection against adverse health effects caused by the inhalation of pollutants because most individuals spend 90% of their time indoors and that indoor air quality is deteriorated by a large variety of sources. Out of these sources radon is a major pollutant and is an important global problem of radiation hygiene. Radon and its progeny are the major contributors in the radiation dose received by general population of the world. Next to cigarette smoking, the inhalation of radon gas and the products of its radioactive disintegration are considered the most significant cause of lung cancer. Due to the potentially serious public health implications of exposure to high levels of radon, the environmental monitoring of radon, thoron and their progeny in some dwellings of Chandigarh, union territory of India has been carried out. The radon-thoron twin dosimeter cups were used for the study. The aim of the study is the possible health risk assessment in the dwellings under consideration. (author)

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

    Science.gov (United States)

    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 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 radon progeny effects and other environmental factors, for every 10 increasing cigarettes smoked in the room. A significant increase of 1.71 in the mean Pdose was found for large room size relative to small room size (90% CI 1.08–2.79) after adjusting for the radon and radon progeny effects as well as other environmental factors. Fireplace usage was found to significantly increase the mean Pdose to 1.71 (90% CI 1.20–2.45) after adjusting for other factors. PMID:19590273

  4. Measurements of radon progeny activity on typical indoor surfaces

    International Nuclear Information System (INIS)

    Knutson, E.O.; Gogolak, C.V.; Klemic, G.

    1992-01-01

    A number of studies aimed at defining how well radon progeny on surfaces can be measured, information that is needed in order to test physical/mathematical models governing indoor radon progeny behaviour, are described. One experiment compared the decomposition on to different surfaces. Only relatively small differences were found among metal, filter paper, broadcloth, corduroy fabric, vinyl wallpaper, glass, and latex paint, but polyethylene film collected two to four times as much as the others, due most likely to electrostatic charge on the plastic surface. Another experiment compared the gamma and gross alpha count methods of measuring surface activity for metal, filter paper, broadcloth and corduroy surfaces. No difference for the surfaces tested was found from which it is concluded that, even for rougher surfaces, progeny atoms deposit mainly on the outer layers. A final experiment compared in situ and surrogate-surface methods for measuring surface deposition. For most tests, the two methods agreed within 30%, and the average ratio was not significantly different from unity. 210 Po is a complication in the in situ method. An unexpected location effect was found in the experiments conducted in houses with high radon concentrations: the deposition on the ceiling was higher than on the surfaces. (author)

  5. Portable devices for monitoring radon and its progeny in air

    International Nuclear Information System (INIS)

    Zhang Huaiqin; Yao Wanyuan; Su Jingling; Liu Jinhua

    1990-01-01

    We have developed two kinds of portable monitoring devices to measure the concentration and potential energy concentration of radon and its progeny in air. The thermoluminescence material CaSO4 (Tm) is used as the detection element. One of the devices is called passive radon monitor. The lowest detectable limit for radon in air is about 1.5 Bq/m 3 , as a sampling time being one week. Good reliability and ease to operate are its main advantages. The second kind of device is called a working level monitor which consists of a miniature remembrane pump and an integrating sampling probe. The lowest detectable limit is about 0.00043 WL (9x10 -9 J/m 3 ) for a sampling time of 6 hours. It weighs only 0.35 kg, but maintenance is necessary sometimes. (author). 6 refs, 2 figs, 4 tabs

  6. Assessing the risks from exposure to radon in dwellings

    International Nuclear Information System (INIS)

    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

  7. Determination of equilibrium factor between radon and its progeny using surface barrier detector for various shapes of passive radon dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Jamil, K. [PINSTECH, Islamabad (Pakistan). Environ. Radiat. Group; Fazal-ur-Rehman [PINSTECH, Islamabad (Pakistan). Environ. Radiat. Group; Ali, S. [PINSTECH, Islamabad (Pakistan). Environ. Radiat. Group; Khan, H.A. [PINSTECH, Islamabad (Pakistan). Environ. Radiat. Group

    1997-03-21

    In the field of radon dosimetry, it is customary to measure radon ({sup 222}Rn) concentration while potential health hazard is due to the radon short-lived progeny. When radon is in secular equilibrium, the measured activity of radon equals the activity of radon`s progeny. However, in practical cases an inequilibrium between radon and its progeny exists which is measured in terms of the equilibrium factor. To determine the equilibrium factor between radon and its progeny in a closed environment various shapes of passive dosimeters based upon solid state nuclear track detectors (SSNTDs) are employed. In order to observe the dependence of equilibrium factor upon shapes or effective volumes, experiments have been performed replacing the SSNTDs with a surface barrier detector in Karlsruhe diffusion chamber, pen-type and box-type dosimeters. Using the collected alpha spectra, the equilibrium factor has been determined for a radon-air mixture in a custom designed radon chamber simulating a closed environment of a room. The results show that the radon equilibrium factor is about 0.20 for different shapes of dosimeters studied in this research. It is concluded that the determination of equilibrium factor between radon and its progeny does not depend upon effective volume or shape of the passive dosimeters using alpha spectroscopic data acquired by surface barrier detector. (orig.).

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

    International Nuclear Information System (INIS)

    Castleman, A.W. Jr.

    1996-01-01

    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

  9. Determination of equilibrium factor between radon and its progeny using surface barrier detector for various shapes of passive radon dosimeters

    International Nuclear Information System (INIS)

    Jamil, K.; Fazal-ur-Rehman; Ali, S.; Khan, H.A.

    1997-01-01

    In the field of radon dosimetry, it is customary to measure radon ( 222 Rn) concentration while potential health hazard is due to the radon short-lived progeny. When radon is in secular equilibrium, the measured activity of radon equals the activity of radon's progeny. However, in practical cases an inequilibrium between radon and its progeny exists which is measured in terms of the equilibrium factor. To determine the equilibrium factor between radon and its progeny in a closed environment various shapes of passive dosimeters based upon solid state nuclear track detectors (SSNTDs) are employed. In order to observe the dependence of equilibrium factor upon shapes or effective volumes, experiments have been performed replacing the SSNTDs with a surface barrier detector in Karlsruhe diffusion chamber, pen-type and box-type dosimeters. Using the collected alpha spectra, the equilibrium factor has been determined for a radon-air mixture in a custom designed radon chamber simulating a closed environment of a room. The results show that the radon equilibrium factor is about 0.20 for different shapes of dosimeters studied in this research. It is concluded that the determination of equilibrium factor between radon and its progeny does not depend upon effective volume or shape of the passive dosimeters using alpha spectroscopic data acquired by surface barrier detector. (orig.)

  10. Assessment of radiological effect of the indoor radon and its progeny

    International Nuclear Information System (INIS)

    Ramachandran, T.V.; Subbaramu, M.C.; Mishra, U.C.

    1988-01-01

    Of all the sources of environmental radiation, radon and its progeny are considered to be responsible for a significant dose to man, especially when they are in enclosed areas like underground mines, caves, cellars, poorly designed and badly ventilated houses. Linear extrapolation from the dose response value of the uranium miners exposed to higher levels of radon and its daughters also suggest that the majority of the lung cancer incidence could be due to radon. Higher indoor radon levels and shift in the disequilibrium of the progeny concentration in dwellings caused by the lower ventilation rate leads to severalfold increase of lung cancer incidence from radon. The large risk which is anticipated calls for further studies in this field and may also lead to the conclusion that the slight, but much feared, burden due to man-made radioactivity could be more than compensated by controlling critical segments of the environmental radioactivity. In this report the study of risk due to breathing of indoor radon is briefly reviewed. Dose equivalent to the exposed tissue of the respiratory tract of the people living in dwellings are evaluated. Like most of the risk assessment of low level radiation, the effort to quantify the effect of radon in terms of death rate dose due to lung cancer attributable to radon levels indoors, has to rely on the extrapolation from the effects of the higher exposure rate. In situations where soil or building materials contain elevated radium levels, living in energy efficient houses may be as dangerous as heavy smoking. (author). 8 tabs., 5 figs., 41 refs

  11. Thoron and radon progeny concentration measurements using direct progeny sensors in HLNRAs of Kerala

    International Nuclear Information System (INIS)

    Mishra, R.; Prajith, R.; Gole, A.C.; Kanse, S.D.; Chougaonkar, M.P.; Sapra, B.K.; Mayya, Y.S.; Jayalekshmi, P.; Nair, Raghu Ram K.

    2010-01-01

    Passive Progeny Dosimeters (PPDs) were deployed in 500 houses in 3 villages namely Allapad, Chavara and Neendakara villages of Karunagapally Taluk of Kollam district of Kerala. Each PPD unit is a combination of a DTPS and a DRPS placed side-by-side for time integrated thoron and radon progeny concentration estimation respectively. The PPDs were suspended vertically in the rooms, such that the nearest distance from any wall or surface was at least 30 cm. These are, as of now, being exposed for a period of 3 months, after which they will be retrieved and analysed by chemical etching and track counting. Simultaneously, external gamma radiation measurements have also been made using a survey meter; these showed a variation from 13 to 118 μR/h in indoors and 21 to 213 μR/h in the outdoor environments. Spot measurements of thoron progeny concentrations were also made in 7 selected houses using the conventional grab filter-paper sampling technique at a flow-rate of 21 min -1 for 30 minutes, followed by alpha counting. The average thoron progeny concentration was found to be 2.0 ± 0.7 Bq m -3 . In the outdoor environment, filter-paper sampling was carried out for 2 hours at 21 min -1 and the thoron progeny concentration was measured as 2.96 Bq m -3 . To corroborate these measurements, a flow mode integrated sampler which uses the DTPS and DRPS elements was used

  12. Wind direction correlated measurements of radon and radon progeny in atmosphere: a method for radon source identification

    International Nuclear Information System (INIS)

    Akber, R.A.; Pfitzner, J.; Johnston, A.

    1994-01-01

    This paper describes the basic principles and methodology of a wind direction correlated measurement technique which is used to distinguish the mine-related and background components of radon and radon progeny concentrations in the vicinity of the ERA Ranger Uranium Mine. Simultaneous measurements of atmospheric radon and radon progeny concentrations and wind speed and direction were conducted using automatic sampling stations. The data were recorded as a time series of half hourly averages and grouped into sixteen 22.5 degrees wind sectors. The sampling interval and the wind sector width were chosen considering wind direction variability (σ θ ) over the sampling time interval. The data were then analysed for radon and radon progeny concentrations in each wind sector. Information about the wind frequency wind speed seasonal and diurnal variations in wind direction and radon concentrations was required for proper data analysis and interpretation of results. A comparison with model-based estimates for an identical time period shows agreement within about a factor of two between the two methods. 15 refs., 1 tab., 5 figs

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

    Science.gov (United States)

    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.

  14. Assessment of nanoparticle surface area by measuring unattached fraction of radon progeny

    Energy Technology Data Exchange (ETDEWEB)

    Ruzer, Lev S. [Ernest Orlando Lawrence Berkeley National Laboratory, Indoor Environment Department (United States)], E-mail: LSRuzer@lbl.gov

    2008-05-15

    A number of studies on the exposure of nanometer aerosols have indicated that health effects associated with low-solubility inhaled particles in the range of 1-100 nm may be more appropriately associated with particulate surface area than mass concentration. Such data on correlation between number, surface area and mass concentration are needed for exposure investigations, but the means for measuring aerosol surface area are not readily available. In this paper we propose a method for particle surface area assessment based on a new approach, deposition of the 'unattached fraction of radon progeny' onto nanometer aerosols.The proposed approach represents a synthesis of:(1) Derived direct analytical correlation between the 'unattached fraction' of radon progeny and surface area particle concentration in the range of 1-100 nm particle diameter;(2) Experimental data on correlation between the unattached fraction of radon progeny and particle surface area for particles with diameter in the range of 44 nm-2.1 {mu}m.

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

    International Nuclear Information System (INIS)

    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 -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 -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

  16. Mass spectrometric studies of the cluster formation of radon progeny

    International Nuclear Information System (INIS)

    Gong, S.L.

    1993-01-01

    A new experimental system is developed to study the cluster formation of radon progeny with neutral molecules in the environment, which includes a modified mass spectrometer and a surface barrier detector. With the system, the cluster research is carried out at molecular level at which the mass of individual cluster formed is measured. A theory is also proposed to treat the cluster formation as a discrete process based on the ion-dipole and dipole-dipole interactions. Comparison between the theory and experiment is given. (author). 16 refs., 6 figs

  17. Mass spectrometric studies of the cluster formation of radon progeny

    Energy Technology Data Exchange (ETDEWEB)

    Gong, S L [Toronto Univ., ON (Canada). Dept. of Chemical Engineering and Applied Chemistry

    1994-12-31

    A new experimental system is developed to study the cluster formation of radon progeny with neutral molecules in the environment, which includes a modified mass spectrometer and a surface barrier detector. With the system, the cluster research is carried out at molecular level at which the mass of individual cluster formed is measured. A theory is also proposed to treat the cluster formation as a discrete process based on the ion-dipole and dipole-dipole interactions. Comparison between the theory and experiment is given. (author). 16 refs., 6 figs.

  18. Lung dosimetry for inhaled radon progeny in smokers

    International Nuclear Information System (INIS)

    Baias, P. F.; Hofmann, W.; Winkler-Heil, R.; Cosma, C.; Duliu, O. G.

    2010-01-01

    Cigarette smoking may change the morphological and physiological parameters of the lung. Thus the primary objective of the present study was to investigate to what extent these smoke-induced changes can modify deposition, clearance and resulting doses of inhaled radon progeny relative to healthy non-smokers (NSs). Doses to sensitive bronchial target cells were computed for four categories of smokers: (1) Light, short-term (LST) smokers, (2) light, long-term (LLT) smokers, (3) heavy, short-term (HST) smokers and (4) heavy, long-term (HLT) smokers. Because of only small changes of morphological and physiological parameters, doses for the LST smokers hardly differed from those for NSs. For LLT and HST smokers, even a protective effect could be observed, caused by a thicker mucus layer and increased mucus velocities. Only in the case of HLT smokers were doses higher by about a factor of 2 than those for NSs, caused primarily by impaired mucociliary clearance, higher breathing frequency, reduced lung volume and airway obstructions. These higher doses suggest that the contribution of inhaled radon progeny to the risk of lung cancer in smokers may be higher than currently assumed on the basis of NS doses. (authors)

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

    International Nuclear Information System (INIS)

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

    1984-01-01

    Eleven portable air cleaing devices have been evaluated for control of indoor concentrations of respirable particles, and their concomitant effects on radon progeny concentrations have been investigated. Of the devices we 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 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. Futhermore, at the low particle concentrations, plateout of the unattached radon progeny was found to be a significant removal mechanism. The overall removal rates due to deposition of attached and unattached progeny have been estimated from these data, and the equilibrium factors for total and unattached progeny concentrations have been calculated as a function of particle concentration. (Author)

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

    International Nuclear Information System (INIS)

    Sextro, R.G.; Offermann, F.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 their concomitant effects on radon progeny concentrations have been investigated. Of the devices we 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 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. Furthermore, at the low particle concentrations, plateout of the unattached radon progeny was found to be a significant removal mechanism. The overall removal rates due to deposition of attached and unattached progeny have been estimated from these data, and the equilibrium factors for total and unattached progeny concentrations have been calculated as a function of particle concentration. 7 references, 2 figures

  1. Field applications of a radon barrier to reduce indoor airborne progeny

    International Nuclear Information System (INIS)

    Culot, M.V.J.; Olson, H.G.; Schiager, K.J.

    1978-01-01

    The use of uranium mill tailings in the foundations of dwellings has resulted in indoor radon progeny concentrations and gamma exposures in excess of levels presently allowed for the general public. An account is given of the applications of an epoxy coating on the indoor faces of the concrete foundations of three buildings in Grand Junction, Colorado. Epoxy barriers were shown to be effective for preventing radon influx into structures. Gamma exposure rates must be analyzed to ensure that buildup behind the barrier will not introduce an unacceptable gamma exposure level. The use of a sealant is especially economical in situations where structural integrity may be jeopardized by physical removal of uranium mill tailings. (author)

  2. Radiation doses from radon and progeny in Irish houses

    International Nuclear Information System (INIS)

    McLaughlin, J.P.

    1985-08-01

    In the United Kingdom, the estimated average annual effective dose equivalent to members of the public from all sources is 2.4 mSv (240 mrem). 40% of this dose is contributed by exposure to radon, and it is not unreasonable to assume that the situation in Ireland is very similar. During 1982-84 a preliminary study of radon and penetrating radiation on 300 Irish houses showed seasonally averaged indoor radon concentrations in the range 3 Bq/m 3 of air to 700 bq/m 3 , with a median value of about 40 bq/m 3 . A national survey of indoor radon has now been undertaken; 3000 households, randomly selected from the electoral register are to be monitored and the result correlated with energy conservation practices. The final part of this document deals with the regulatory aspects of radon control and reviews the practices for reduction of indoor radon daughter doses presently in hand in Scandinavia. An appendix of radiation units and terms is also given

  3. Effect of ventilation rate on concentrations of indoor radon and its progenies

    International Nuclear Information System (INIS)

    Wang Chunhong; Liu Yanyang; Liu Fudong; Liu Senlin; Chen Ling

    2012-01-01

    To study concentrations of indoor radon and its progenies, ventilation rates and their corresponding concentrations of indoor radon and its progenies were measured using tracer-gas dilution method. Results show that both ventilation rates and concentrations of indoor radon varied insignificantly and radon concentration were higher than the outdoor environment while doors and windows were all closed with air-conditioner on and off respectively; the concentrations declined and close to the outdoor level when doors and windows were all open with ventilators in operation. Accordingly, in modern life, especially in summer, people's preference for air-conditioners but natural ventilation would result in an increase of indoor radon concentration. (authors)

  4. Concentration of Radon, thoron and their progeny levels in different types of floorings, walls, rooms and building materials

    International Nuclear Information System (INIS)

    Sathish, L. A.; Nagaraja, K.; Ramanna, H. C.; Nagesh, V.; Sundareshan, S.

    2009-01-01

    Radon, thoron and their progenies are the most important contributions to human exposure from natural sources. Radon exists in soil gas, building materials, Indoor atmosphere etc. Among all the natural sources of radiation dose to human beings, inhalation of radon contributes a lot. The work presented here emphasizes the long term measurements of radon, thoron and their progeny concentrations in about 100 dwellings using solid state nuclear track detectors. Materials and Methods: Measurements were made using dosimeters and the concentrations were estimated by knowing the track density of films through spark counter, and sensitivity factor for bare, filter and membrane films. Results: Presence of radon and thoron in houses is the effect of several aspects such as the activity concentrations of uranium, radium and thorium in the local soil, building materials, ventilation of houses and also entry of radon into houses through the cracks in floor/wall. Conclusion: The observations reveal that the concentrations of radon and/or thoron are relatively higher in granite than in concrete, cement and bricks. In continuation to this the concentration observed in bathrooms is more compared to kitchen bedroom and living rooms. This study discloses that the residential rooms of good ventilation will avoid the health hazards due to radon and its rich materials.

  5. The study of thoron and radon progeny concentrations in dwellings in Japan

    International Nuclear Information System (INIS)

    Guo, Q.; Shimo, M.; Ikebe, Y.

    1992-01-01

    Ths paper aims to make a comparison of different concentrations of thoron ( 220 Rn) progeny and radon ( 222 Rn) progeny in different kinds of dwellings. The potential alpha energy concentrations and the effective dose equivalent caused by thoron and radon progeny, respectively, have also been estimated. The measurements were carried out in 23 dwellings. The results indicate that thoron progeny concentrations indoors might be strongly affected by the type of building material used. Traditional Japanese buildings made with mud may have high thoron progeny concentrations of about 3.52 Bq.m -3 and a concentration ratio of thoron progeny to radon progeny of about 0.5, whereas in concrete dwellings thoron progeny concentrations are about 0.72 Bq.m -3 and the concentration ratio of thoron progeny to radon progeny is about 0.1. The annual effective dose equivalent of thoron progeny is 1.23 mSv in mud dwellings and 0.25 mSv in concrete dwellings. (author)

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

    International Nuclear Information System (INIS)

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

    1984-11-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  8. Measurement of radon, thoron and their progeny concentrations in the dwellings of Pauri Garhwal, Uttarakhand, India

    International Nuclear Information System (INIS)

    Joshi, Veena; Bijalwan, Pramesh; Rawat, Jasbir; Yadav, Manjulata; Ramola, R.C.; Mishra, Rosaline

    2015-01-01

    It is well known that inhalation of radon, thoron and their progeny contribute more than 50% of natural background radiation dose to human being. The time integrated passive measurements of radon, thoron and their progeny concentrations were carried out in the dwellings of Pauri Garhwal, Uttarakhand, India. The measurements of radon and thoron concentrations were performed by LR-115 detector based single entry Pin-Hole dosimeter while for the measurement of progeny concentrations, LR-115 deposition based DTPS/DRPS technique was used. The experimental techniques and results obtained are discussed in detail. (author)

  9. Examination of the influence of water-heated central heating systems on the levels of radon and radon progeny in the workplace

    International Nuclear Information System (INIS)

    Marley, F.; Denman, A.R.; Phillips, P.S.

    2000-01-01

    A series of continuous real-time radon and progeny measurements, together with passive etched-track detector measurements returning average values, were undertaken in commercial premises in Northamptonshire. Detailed measurements over several months in two separate buildings show that the level of both radon and progeny are determined to a major extent by the influence of the operation and timing of the central heating systems in place. Both buildings studied are similar in construction to many single-storey domestic properties. The operative heating system reduced the radon and progeny levels relative to the non-operating mode by over 40% during the heating period of a normal working day. The variation in temperature during this time was generally less than 3 deg. C, indicative of a heat retentive building. Because the equilibrium (F) fraction is reduced during the heating period, the reductions in radon and progeny are not uniform. In the workplaces studied, the work-cycle was normally limited to 0900-1700 hours Monday to Friday, the period when the lowest values were recorded. Average daily values would therefore overstate by more than 50% the maximum potential dose during normal attendance hours. The corollary is that living under similar circumstances in domestic environments, the operation and timing of this type of heating regime may well result in higher exposure in the home than at work

  10. Estimation of radiological dose from radon, thoron and their progeny levels in the dwellings of Shivamogga district, Karnataka, India

    International Nuclear Information System (INIS)

    Rangaswamvi, D.R.; Sannappa, J.; Srinivasa, E.

    2018-01-01

    Among all natural radiation exposure to man, inhalation of radon, thoron and their progenies are the major contributor (50 %) to the dose from ionizing radiation received by the general population. Based on the results of epidemiological studies in Europe and North America, the World Health Organization (WHO) has recommended reducing the indoor radon reference level from 200 to 100 Bq.m -3 . In view of this, focus has now been given for simultaneous measurement of radon, thoron and their progeny concentration in indoor air and also to estimate radiological dose in the dwellings of the Shivamogga district. The geology of the Shivamogga district comprises different types of rock formation such as granites, schists, magnetites and gneisses, Meta basalt, laterites, quartz and chlorite schist, Graywacke etc. Present study was concentrating more in granite bed rock regions along with their surrounding regions

  11. Cardiovascular Mortality Caused by Exposure to Radon

    International Nuclear Information System (INIS)

    Johnson, J. R.; Duport, P.

    2004-01-01

    Cardiovascular diseases (CVD) are reported as the cause of morbidity and mortality in humans exposed to (high) therapeutic doses of radiation, A-bomb explosions, accidental (Chernobyl liquidators) and occupational level of radiation while CVD risk does not appear to be elevated in other populations exposed to radiation CVD mortality also appears to be elevated, proportionally with radon progeny exposure in Newfoundland fluorspar miners. In addition, radiation exposure does not seem to increase and may indeed decrease CVD mortality or morbidity in mammals exposed to radiation in the laboratory. We have calculated the doses to blood and coronary artery wall from radon and progeny, and have concluded radon exposure may indeed increase the incidence of cardiovascular diseases and that a thorough investigation of that risk is justified, even at environmental and occupational levels. These contradictory observations suggest that radiation may be considered as one of many risk factors for cardiovascular diseases. As such, it may be necessary to reduce not only other risk factors as far as possible, but also to minimize exposures to radiation to further reduce the burden of cardiovascular diseases in the population. (Author) 27 refs

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  13. Exposure to radon

    International Nuclear Information System (INIS)

    1988-01-01

    Part 3 is given of the Code of Practice approved by the UK Health and Safety Commission with the consent of the Secretary of State for the purpose of providing practical guidance with respect to the provisions of the Ionising Radiations Regulations 1985. Part 3 gives specific guidance on the application of the Regulations to certain work involving exposure to isotopes of radon and their decay products. Aspects covered in the Regulations include restriction of exposure, dose limits, controlled areas, radiation protection advisers and supervisors, dosimetry and area monitoring. (U.K.)

  14. Prototype exposure chamber of radon for animal experiments

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Yuji; Koizumi, Akira; Yonehara, Hidenori; Shimo, Michikuni; Inaba, Jiro [National Institute of Radiological Sciences, Chiba (Japan)

    1998-12-31

    To evaluate a dose conversion factor from the `Working Level of Month` (WLM) of radon to the absorbed dose (mGy), the quality of radon and its progeny was assessed, and exposures controlled for each deposition region were planed as follows: 1) exposure of radon gas to the entire respiratory tract, 2) exposure of `unattached` fractions to the upper respiratory tract, 3) exposure of `attached` fractions onto ultrafine particles to the deep lung, 4) exposure of `attached` fractions onto fine particles to the lower respiratory tract, 5) exposure of `attached` fractions onto coarse particles to the upper respiratory tract. In this preliminary study, a prototype exposure system of radon and its progeny for small rodents was designed. A whole body exposure chamber with a volume of about 0.5 m{sup 3} was used, which it held 20 rats. The aging and mixing chamber separated by the exposure chamber had a volume of about 1 m{sup 3}. As career aerosols of radon progeny, carnauba wax aerosols as solid particles, DOS aerosols as liquid particles and NaCl aerosols as hygroscopic particles were selected. These aerosols generated using a vaporization-condensation method and/or an electrical classification method were almost monodisperse with {sigma}{sub g} of <1.2. The monitoring data on biologically related gases showed an importance in the oxygen injection system and the carbon dioxide absorption system. (author)

  15. Study of radon progeny distribution and radiation dose rate in the atmosphere

    International Nuclear Information System (INIS)

    Fujinami, Naoto

    2009-01-01

    The absorbed dose rate in air of airborne gamma-ray and the concentration of radon progeny in surface air have been observed continuously in Maizuru, Japan. When data observed on fine days were plotted, with dose rate as ordinate and contraction as abscissa, these points traced with a lapse of time illustrated an anticlockwise looping for each day. This result suggests that the variation of absorbed dose rate lags behind that of concentration of radon progeny; this is due to the delay time incurred as the concentration level gradually varies from ground surface to upper air. Radon progeny concentrations in precipitation and in surface air have been observed there in order to study the relationship between the two concentrations and the influence of precipitation patterns on the concentration in precipitation. Results obtained from analysis of the observed data suggest that radon progeny in precipitation originate mainly from scavenging within the cloud (rainout) and not from that below the cloud (washout). (author)

  16. Role of radon and its progeny in the origin and evolution of life on earth

    International Nuclear Information System (INIS)

    Subba Ramu, M.C.; Vohra, K.G.

    1980-01-01

    The role of natural ionising radiations from radon and its progeny in catalysing certain chemical reactions and aiding certain biological phenomena leading to the formation and evolution of life on earth is explained with illustrations. (M.G.B.)

  17. Measurement of the deposited activity of the short-lived radon progeny in the human respiratory tract

    International Nuclear Information System (INIS)

    Vezzu, G.; Butterweck-Dempewolf, G.; Schuler, C.

    1998-01-01

    Volunteers were exposed in the radon chamber at Paul Scherrer Institut to an atmosphere enriched with highly unattached radon progeny. The deposited radon progeny activity in the respiratory tract of the volunteers was determined using a low level in-vivo counter. The detector arrangement and its calibration for the measurement of deposited radon progeny activity is described and the results for a mouth and a nose breathing volunteer are presented. For the nose breathing volunteer 55% of the deposited radon progeny activity was located in the head and the remaining 45% in the chest whereas for the mouth breathing volunteer 25% was located in the head and the remaining 75% in the chest. A mean clearance half-life for the deposited radon progeny from the respiratory tract of (2±1) h was obtained from the analyses of the temporal behaviour of the deposited radon progeny activity in the head. (orig.)

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

    Science.gov (United States)

    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

  19. Radon exposure and lung cancer

    International Nuclear Information System (INIS)

    Planinic, J.; Vukovic, B.; Faj, Z.; Radolic, V.; Suveljak, B.

    2003-01-01

    Although studies of radon exposure have established that Rn decay products are a cause of lung cancer among miners, the lung cancer risk to the general population from indoor radon remains unclear and controversial. Our epidemiological investigation of indoor radon influence on lung cancer incidence was carried out for 201 patients from the Osijek town. Ecological method was applied by using the town map with square fields of 1 km 2 and the town was divided into 24 fields. Multiple regression study for the lung cancer rate on field, average indoor radon exposure and smoking showed a positive linear double regression for the mentioned variables. Case-control study showed that patients, diseased of lung cancer, dwelt in homes with significantly higher radon concentrations, by comparison to the average indoor radon level of control sample. (author)

  20. Local deposition patterns of inhaled radon progeny in human bronchial airways

    International Nuclear Information System (INIS)

    Heistracher, T.; Hofmann, W.; Balashazy, I.

    1996-01-01

    The local distribution of radon decay products deposited within bronchial bifurcations, particularly the formation of hot spots, may be more relevant for the determination of cellular doses in bronchial tissue than the commonly computed deposition efficiency, which is conceptually equivalent to the assumption of a uniform nuclide distribution. It is well known that the initial states of lung cancer in humans preferably occur in upper airways close to the cardinal location. In this study we use a recently developed geometric approach of a physiologically realistic bifurcation to demonstrate the site sensitivity of radon progeny deposition for two particle sizes, which are representative of the unattached and attached fraction of radon progeny

  1. Exposure to radon in Australian tourist caves

    International Nuclear Information System (INIS)

    Solomon, S.B.; Langroo, R.; Lyons, R.G.

    1994-01-01

    In 1991 the International Commission on Radiological Protection(ICRP) produced guidelines and recommendations dealing with workplace exposure to elevated background radiation, in particular, the risk associated with the inhalation of radon and radon progeny. An intervention level of 1000 Bq m -3 has been proposed. Australia has over 40 tourist caves, under the management of the various State Departments or private groups. The limited data available on radon levels in Australian caves would suggest that some of these caves may be in excess of the proposed intervention level, thus presenting a potential health risk for the cave guides. This paper summarises the current information on radon in Australian caves and describes the proposed methodologies to be used for a Worksafe Australia-funded survey of radon levels in Tourist caves within Australia. This survey is to be carried out jointly by researchers at the Australian Radiation Laboratory, University of Auckland and the University of Sydney, during 1994 and 1995. 7 refs., 3 tabs

  2. Radon exposures in the UK

    International Nuclear Information System (INIS)

    O'Riordan, M.C.

    1992-01-01

    Public and occupational health protection against radon is provided in the UK. Protection is advised where geological conditions cause high concentrations in domestic and commercial buildings. These circumstances are described and the resulting exposures reviewed. An account is given of the limitation scheme for radon in the home and the regulatory scheme for radon at work, the manner in which they are implemented, and the degree to which they are successful. (author)

  3. Evaluation of several air cleaners for reducing indoor radon progeny

    International Nuclear Information System (INIS)

    Hopke, P.K.; Jensen, B.; Montassier, N.

    1994-01-01

    Over the past several years, studies have been made of the effectiveness of several kinds of air cleaners in removing radon decay products from indoor air using a recently developed automated, semi-continuous measurement system that can determine the activity-weighted size distributions in occupied homes. Measurements of activity-weighted size distributions and radon concentrations were made every 90 min in a home with a high air exchange rate. A week-long series of measurements was made for the home with no cleaner operating and a similar set of measurements were made for each of the air cleaners. Two different types of air cleaners were tested in this study; filtration units (two different designs from two different manufacturers) and two ion generator/fan systems (identical design NO-RAD systems, but from two different manufacturers). It was found that the filtration units resulted in a median reduction in exposure of 15% and 36% for the two units and corresponding dose reductions of 32% and 53%. The two NO-RAD systems produced 37% and 10% reductions in the median exposure, but the reductions in the median dose were 49% and 46%. (author)

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

    International Nuclear Information System (INIS)

    Hopke, P.K.

    1996-09-01

    This report completes Clarkson University's study of the chemical and physical behavior of the 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 2 , ethylene, and H 2 S to lower vapor pressure compounds and determine the role of gas phase additives such as H 2 O and NH 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 218 PoO x + in O 2 at low radon concentrations

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

    International Nuclear Information System (INIS)

    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. Exposure due to radon in homes - an IAEA perspective

    International Nuclear Information System (INIS)

    Navratilova-Rovenska, K.; Boal, T.; Colgan, T.

    2014-01-01

    The results of miner and residential epidemiology studies provide statistically strong evidence of harmful effects of exposure due to radon and its progeny. With the publication of the fifth edition of the International Basic Safety Standards, of the World Health Organizations Handbook on Indoor Radon and new ICRP statement on radon, there is increased interest from the public health and radiation protection authorities on controlling exposure due to radon and its progeny.The IAEA Safety Requirements publication 'Radiation Protection and Safety of Radiation Sources: International Basic Safety Standards' sets out requirements on governments for control of existing exposure situations, which includes exposure due to radon. The types of situation that are included in the scope of existing exposure situations include exposure in workplaces for which the exposure due to radon is not required by or directly related to the work and for which annual average activity concentrations due to 222 Rn must not exceed a maximum reference level of 1000 Bq/m 3 annual activity concentration, as well as exposure in dwellings and in other buildings with high occupancy factors for members of the public for which the reference level must not exceed a maximum value of 300 Bq/m 3 . These requirements include: collecting data on the activity concentrations of radon in dwellings and other buildings with high occupancy by the public; providing information on exposure due to radon and the associated health risks; and if necessary, to develop an action plan for controlling public exposure to radon. The IAEA has developed a Safety Guide to provide guidance on developing the radon action plan: 'Protection of the Public against Exposure Indoors due to Radon and Other Natural Sources of Radiation'. This presentation will summarize the information on the assistance that the IAEA is currently providing to IAEA Member States to develop radon action plans. These activities include

  7. Wire screens as a tool for survey measurements of the unattached radon progeny in mines

    International Nuclear Information System (INIS)

    Janica, R.

    1996-07-01

    The radon hazard in mines is assessed by measuring the radioactivity accumulated on filters through which air is forced to flow. The filter collects both forms of the short-lived radon progeny, attached and unattached, and, therefore, the assessment is based on the measurement of the total radon progeny. Because of the special radiological significance of the unattached fraction of the short-lived radon progeny, the estimation of the radiation hazard to miners would be improved if the unattached fraction could be measured. This report describes two methods of measurement for the simultaneous determination of the unattached and the total radon progeny. The proposed methods comply with the criterion of practicality (imposed by the working conditions in the mine environment), that is, they are implemented using standard survey equipment and simple procedures. Both methods use wire screens to collect, preferentially, the unattached fraction. According to the first method, air is sampled through a wire screen and a backup filter, and the radioactivity accumulated on both the filter and the wire screen are measured separately using standard counting protocols (e.g. the Kusnetz protocol). The wire screen's efficiency for collecting the unattached radon progeny is determined, in advance, under laboratory conditions. The method assumes the validity of the collection efficiencies when the screens are used under field conditions. To avoid the uncertainty of the lab-determined collection efficiency, a new measuring method was proposed based on the sampling of air through two screens in series and a backup filter. The measurement of the ratio of the activities deposited on both screens allows an estimation of the screen collection efficiency under field conditions. Once this is done, the 'unattached fraction' and total radon progeny are determined by counting only one of the screens and the backup filter as described in the previous method. (author). 73 refs., 8 tabs., 21 figs

  8. Temporal and vertical variations radon and its progeny related to atmospheric electrical conductivity

    International Nuclear Information System (INIS)

    Pruthvi Rani, K.S.; Chandrashekara, M.S.; Paramesh, L.

    2015-01-01

    Atmospheric radon, its progeny, electrical conductivity and meteorological parameters such as wind, temperature, humidity, pressure and rainfall were continuously monitored during 2012 to 2014 at one location in Mysuru city. The annual mean atmospheric radon concentration at the study location was found to be 16.4 Bqm -3 . The diurnal cycle of radon and its progeny show a peak in the early morning hours followed by a drastic decrease after sunrise and rising to a second peak in the afternoon. It was found that the stability of the atmosphere and ambient temperature played a major role in the diurnal variations. Higher concentrations of radon and its progeny were observed in winter and lower values in summer. This may due to the variations in origin of air mass and meteorological parameters. Wind direction analyses reveal that in sectors with air which has spent a longer period over the granitic region and low wind speeds will lead to higher concentrations of radon. Atmospheric electrical conductivity near the ground is mainly due to the ionization from radon and its progeny. The diurnal variations of conductivity and ionization rate due to radon and its individual progeny were of similar trend. In addition its significant dependence on meteorological parameters is confirmed. The vertical variations of atmospheric electrical conductivity were studied at different heights up to 250 m from the ground level. Higher values were observed close to the ground surface, there was a rapid reduction up to about 10 m and beyond that the conductivity gradually decreases. The diurnal conductivity cycle is studied at 10 m and 100 m showed the expected similar trend at both the heights but early morning maxima were considerably different, this confirms the accumulation of radon gas close to the ground surface during night time leading to increase of conductivity values. (author)

  9. Effect of natural ventilation on radon and radon progeny levels in houses. Rept. for Apr 90-Sep 91

    International Nuclear Information System (INIS)

    Cavallo, A.; Gadsby, K.; Reddy, T.A.; Socolow, R.

    1991-01-01

    The paper discusses the effect of natural ventilation on radon and radon progeny levels in houses. Contradicting the widely held assumption that ventilation is ineffective in reducing indoor radon concentrations, experiments in a research house have shown that the basement radon level can be reduced by a factor of 5 to 10 using only natural ventilation. Measurement of the outdoor-basement pressure differential and the radon entry rate shows that this unexpectedly large reduction in indoor radon levels is caused by two complementary physical processes: (1) the obvious one, dilution, which lowers radon concentrations by adding uncontaminated outdoor air; and (2) although less evident, introducing a pressure break in the system through an open basement window which, in turn, reduces the outdoor-basement pressure differential and the rate at which radon-laden soil gas is drawn into the house. The radon entry rate was found to be a linear function of basement depressurization up to a differential pressure of about 4 Pa, as would be expected for laminar soil gas flow; opening two basement windows approximately doubled the building air exchange rate and reduced the radon entry rate by up to a factor of 5

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

    Energy Technology Data Exchange (ETDEWEB)

    Trassierra, C. Vargas [Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, FR (Italy); Stabile, L., E-mail: l.stabile@unicas.it [Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, FR (Italy); Cardellini, F.; Morawska, L. [National Institute of Ionizing Radiation Metrology (INMRI-ENEA), Rome (Italy); Buonanno, G. [Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, FR (Italy); International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane (Australia)

    2016-08-15

    Highlights: • Investigation of the interaction between particles and radon progeny dynamics. • Measurements of particles emitted by different indoor sources. • Tests performed in a controlled radon chamber. • Particle size strongly influences the radon progeny dynamics. • Particle surface area concentration is the key parameter of the radon-particle interaction. - Abstract: 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.

  11. Attached and Unattached Activity Size Distribution of Short-Lived Radon Progeny (214Pb) and Evaluation of Deposition Fraction

    International Nuclear Information System (INIS)

    Mohamed, A.; Ahmed, A.A.; Ali, A.E.; Yuness, M.

    2009-01-01

    Inhalation of 2 '2 2 Rn progeny in the domestic environment contributes the greatest fraction of the natural radiation exposure to the public. Dosimetric models are most often used in the assessment of human lung doses due to inhaled radioactivity because of the difficulty in making direct measurements. These models require information about the parameters of activity size distributions of radon progeny. The current study presents measured data on the attached and unattached activity size distributions of radon progeny in indoor air in El-Minia, Egypt. The attached fraction was collected using a low pressure Berner cascade impactor technique. A screen diffusion battery was used for collecting the unattached fraction. Most of the attached activities for 222 Rn progeny were associated with aerosol particles of the accumulation mode. The mean activity median aerodynamic diameter (AMAD) of this mode for 21 4 P b was determined to be 401 nm with relative mean geometric standard deviation of 2.96. The mean value of specific air activity concentration of 214 Pb associated with that mode was determined to be 4.74 %0.44 Bq m -3 . The relative mean geometric standard deviations of unattached 214 Pb was determined to be 1.21 with the mean activity thermodynamic diameter (AMTD) of 1.2 nm. The mean unattached activity concentration of 214 Pb was found to be 0.44%0.14 Bq m-3. Based on the obtained results of radon progeny size distributions (unattached and attached), the deposition fractions in each airway generation of the human lung were evaluated by using a lung deposition model

  12. Effect of radon and its progeny on the expression and mutation of p53 in lung tissues of mice

    International Nuclear Information System (INIS)

    Piao Chunnan; Tian Mei; Liu Jianxiang; Ruan Jianlei; Su Xu

    2010-01-01

    Objective: To explore the effect of radon and its progeny on the expression and mutations of p53 in lung tissue of mouse model. Methods: Apoptosis was detected by terminal deoxynucleotidy transferase-mediated dUTP-biotin nick end labeling. The expression of p53 gene was analyzed by immunohistochemistry, Western blot and realtime-PCR. PCR-SSCP was used to detect the mutation of p53 in lung tissues. Results: Compared with those in the control group, the apoptotic index were increased significantly in 30 WLM and 60 WLM groups (t=18.11, -10.30, P<0.05). The p53 protein was increased significantly (t=-11.08, P<0.05; t=-7.00, P<0.05) in 30 WLM and 60 WLM groups. The mutation of p53 gene was not detected in lungs of radon-exposure mice. Conclusions: Lung and bronchus might be the targets of radon and its progeny, and p53 gene plays an important role in the progression of radon-induced lung injury. (authors)

  13. Indoor radon and its progeny levels in new type houses in rural area of Hubei

    International Nuclear Information System (INIS)

    He Quan; Xiong Zhaoxing; He Zuan; Zheng Youqing

    1993-01-01

    Using Cluster Sampling method, indoor radon of 54 rooms and radon progeny potential alpha-energy concentrations of 200 rooms were measured in the new type brick-concrete 2-storey flats and old type brick-wood single-storey residences in the rural area. Instant and cumulative samplings and measurements were made. The average per capita residential area of the surveyed houses was 28.1 m 2 , clear height 3.6 m. The geometric means of indoor radon concentration were 18.22 Bq.m -3 and 15.93 Bq.m -3 for storied and single-storey buildings, respectively; radon progeny potential alpha-energy concentrations were 2.62 mWL and 2.54 mWL, correspondingly. In storied buildings, the arithmetic mean of indoor cumulative radon concentration was 25.56 Bq.m -3 in summer, and 37.94 Bq.m -3 in winter. The annual effective dose equivalent of radon progeny inhaled indoors and outdoors was 0.80 mSv. (orig.). (6 refs., 1 fig., 5 tabs.)

  14. Assessing the deposition of radon progeny from a uranium glass necklace

    International Nuclear Information System (INIS)

    Hanse, M.F.; Moss, G.R.

    2015-01-01

    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. (authors)

  15. DOSEmanPRO - active electronic online personal air sampler for detection of radon progeny long lived alpha nuclides

    International Nuclear Information System (INIS)

    Streil, T.; Oeser, V.

    2002-01-01

    calculated and displayed online during the exposure time, given dose limits can be watched by an alert function. Rapid changes of the concentration can be detected and the dose gets available in its time distribution as well. The PC-based dose management provides an administrator desk for stuff planning and enables the channel of measurement pre-set. The standard infrared interface handles the data communication with a PC. As required, the electronic dosimeter is easy to handle and rugged enough to withstand the rough working conditions. The device is water protected and can work up to 98 % relative humidity. The smallest adjustable integration time is 1 min (correspond to a radon progeny detection limit of nearly 6 Bq/m 3 ). The following acquired measurement data will be stored to the internal memory (capacity 300 cycles): 60 channel sum spectra, time distribution of 5 region of interest (ROI), PAEC, PAEE, ERC and dose, average values. Free ROI set up enables for instance to focus on Po218, adjust the next ROI on Po214, one on Po212, the next on U238/Ra226 3,5 ... 4.9 MeV and the last on Pu239/ Po210 / Am241 4.9 ... 5.6 MeV. DOSEman Pro is a unique continuous WL monitor with a efficiency in the order of the state-of-the-art devices but cost-effective with a price that is a tenth of a progeny monitor. DOSEman Pro will fit the requirements for personal dosimetry as well as local dosimetry or long term monitoring. The system can be used for the online detection with alert function of 'dirty bombs'. First results from plutonium, polonium and radium in air will be presented. (author)

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

    International Nuclear Information System (INIS)

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

    1991-01-01

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

  17. Modelling the effect of non-uniform radon progeny activities on transformation frequencies in human bronchial airways

    International Nuclear Information System (INIS)

    Fakir, H.; Hofmann, W.; Aubineau-Laniece, I.

    2006-01-01

    The effects of radiological and morphological source heterogeneities in straight and Y-shaped bronchial airways on hit frequencies and Micro-dosimetric quantities in epithelial cells have been investigated previously. The goal of the present study is to relate these physical quantities to transformation frequencies in sensitive target cells and to radon-induced lung cancer risk. Based on an effect-specific track length model, computed linear energy transfer (LET) spectra were converted to corresponding transformation frequencies for different activity distributions and source - target configurations. Average transformation probabilities were considerably enhanced for radon progeny accumulations and target cells at the carinal ridge, relative to uniform activity distributions and target cells located along the curved and straight airway portions at the same exposure level. Although uncorrelated transformation probabilities produce a linear dose - effect relationship, correlated transformations first increase depending on the LET, but then decrease significantly when exceeding a defined number of hits or cumulative exposure level. (authors)

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

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, L. A.; Hadler, J. C.; Lixandrão F, A. L.; Guedes, S.; Takizawa, R. H. [Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, UNICAMP, 13083-970 Campinas, SP (Brazil)

    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. Characteristics of radon and its progeny concentrations in air-conditioned office buildings in Tokyo

    International Nuclear Information System (INIS)

    Tokonami, S.; Furukawa, M.; Shicchi, Y.; Sanada, T.; Yamada, Y.

    2003-01-01

    A series of measurements were carried out to understand the characteristics of radon and its progeny in air-conditioned office buildings. Long-term measurements of radon were made with etched track detectors. Continuous measurements of radon and its progeny concentrations were also conducted in some buildings to study their temporal variations. The results show that radon and its progeny concentrations routinely varied along with working activities. They are generally low while people are working, due to air conditioning, whereas they rise steadily after the air conditioning stops. When considering action levels not only in homes but also workplaces, attention should be paid to annual doses from the viewpoint of radiation protection. The annual dose is generally estimated with a long-term measurement of radon concentration using a passive device such as an etched track detector. Since its reading corresponds to a long-term average concentration regardless of working hours, the annual dose will be overestimated. When comparing a real dose after considering the working hours, they differ by a factor of more than 2. (author)

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

    International Nuclear Information System (INIS)

    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. Measurements are being made to obtain information on both location- and season-dependent variation of radon and radon progeny. Simultaneous measurements are made quarterly on both upper and lower levels of each house. Grab samples of air are collected and analyzed for radon using a modified Lucas cell technique. Short-term (10-minute) samples of airborne particulate material are collected and analyzed for radon progeny. One-week integrated measurements of working levels are made once each quarter using modified thermoluminescent dosimeters. Both three- and twelve-month integrated measurements of radon using track-etch monitors are being made. 19 references, 1 figures

  1. Particle size distribution of the radon progeny and ambient aerosols in the Underground Tourist Route "Liczyrzepa" Mine in Kowary Adit

    Science.gov (United States)

    Wołoszczuk, Katarzyna; Skubacz, Krystian

    2018-01-01

    Central Laboratory for Radiological Protection, in cooperation with Central Mining Institute performed measurements of radon concentration in air, potential alpha energy concentration (PAEC), particle size distribution of the radon progeny and ambient aerosols in the Underground Tourist-Educational Route "Liczyrzepa" Mine in Kowary Adit. A research study was developed to investigate the appropriate dose conversion factors for short-lived radon progeny. The particle size distribution of radon progeny was determined using Radon Progeny Particle Size Spectrometer (RPPSS). The device allows to receive the distribution of PAEC in the particle size range from 0.6 nm to 2494 nm, based on their activity measured on 8 stages composed of impaction plates or diffusion screens. The measurements of the ambient airborne particle size distribution were performed in the range from a few nanometres to about 20 micrometres using Aerodynamic Particle Sizer (APS) spectrometer and the Scanning Mobility Particle Sizer Spectrometer (SMPS).

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

    International Nuclear Information System (INIS)

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

    2015-01-01

    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. (authors)

  3. Diurnal Variations of Equilibrium Factor and Unattached fraction of Radon Progeny in Some Houses and Laboratories

    International Nuclear Information System (INIS)

    Lee, Seung Chan; Kang, Hee Dong; Kim, Chang Kyu; Lee, Dong Myung

    2001-01-01

    The variation characteristics of radon concentration, equilibrium equivalent concentration and equilibrium factor in some house and laboratory buildings have been studied. The variation of equilibrium factor and the unattached fraction of radon progeny with ventilation condition have been also estimated. The averages of radon concentration, equilibrium equivalent concentration and equilibrium factor were 30 Bq m -3 , 19.6 Bq m -3 and 0.65 in seven houses, while 55.0 Bq m -3 , 31.9 Bq m -3 and 0.58 in three laboratory buildings, respectively. The diurnal variation of radon concentration, equilibrium equivalent concentration and equilibrium factor in indoor showed a typical pattern that the radon concentration, equilibrium equivalent concentration and equilibrium factor increased at dawn and morning, while decreased at midday and evening. While the equilibrium factor rate deceased in the indoor environment which was well ventilated, the unattached fraction of radon progeny increased. The equilibrium factor was in proportion to air pressure and humidity of indoor, whereas in inverse proportion to temperature

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

    Science.gov (United States)

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

  5. A method for determining an indicator of effective dose calculation due to inhalation of Radon and its progeny from in vivo measurements

    International Nuclear Information System (INIS)

    Estrada, Julio Jose da Silva

    1994-01-01

    Direct measurement of the absolved dose to lung tissue from inhalation of radon and its progeny is not possible and must be calculated using dosimetric models, taking into consideration the several parameters upon which the dose calculation depends. To asses the dose due to inhalation of radon and its progeny, it is necessary to estimate the cumulative exposure. Historically, this has been done using WLM values estimated with measurements of radon concentration in air. The radon concentration in air varies significantly, however, in space with time, and the exposed individual is also constantly moving around. This makes it almost impossible to obtain a precise estimate of an individual's inhalation exposure. This work describes a pilot study to calculate lung dose from the deposition of radon progeny, via estimates of cumulative exposure derived from in vivo measurements of 210 Pb, in subjects exposed to above-average radon and its progeny concentrations in their home environments. The measurements were performed in a whole body counter. With this technique, the exposed individuals become, in affect, their own samplers and dosimeters and the estimate of cumulative exposure is not affected by the variation of the atmospheric concentration of radon and its progeny in time and space. Forty individuals identified as living in homes with radon levels ranging from about 740 Bq/m 3 to 150.000 Bq/m 3 were measured. Also, additional 34 measurements were made on personnel from NYUMC/NIEM who live in a residential area surrounding the laboratory in which the levels of radon have been shown to be at below average values. To realize these measurements a methodology was developed to determine the subject's background, using a head phantom made with a cubic plastic container containing known amounts of potassium and calcium dissolved in four liters of water. The effective doses calculated from the in vivo measurements are compared to effective doses estimated, for the same

  6. Estimation of radon progeny equilibrium factors and their uncertainty bounds using solid state nuclear track detectors

    International Nuclear Information System (INIS)

    Eappen, K.P.; Mayya, Y.S.; Patnaik, R.L.; Kushwaha, H.S.

    2006-01-01

    For the assessment of inhalation doses due to radon and its progeny to uranium mine workers, 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) are best suited for this purpose. These generally contain two SSNTDs, one placed inside the cup to measure only the radon gas concentration and other outside the cup for recording tracks due to both radon gas and the progeny species. However, since one obtains only two numbers by this method whereas information on four quantities is required for an unambiguous estimation of dose, there is a need for developing an optimal methodology for extracting information on the equilibrium factors. Several techniques proposed earlier have essentially been based on deterministic approaches, which do not fully take into account all the possible uncertainties in the environmental parameters. Keeping this in view, a simple 'mean of bounds' methodology is proposed to extract equilibrium factors based on their absolute bounds and the associated uncertainties as obtained from general arguments of radon progeny disequilibrium. This may be considered as reasonable estimates of the equilibrium factors in the absence of a knowledge of fluctuation in the environmental variables. The results are compared with those from direct measurements both in the laboratory and in real field situations. In view of the good agreement found between these, it is proposed that the simple mean of bounds estimate may be useful for practical applications in inhalation dosimetry of mine workers

  7. Radon progeny dose conversion coefficients for Chinese males and females

    Energy Technology Data Exchange (ETDEWEB)

    Yu, K.N. E-mail: peter.yu@city.edu.hk; Cheung, T.T.K.; Haque, A.K.M.M.; Nikezic, D.; Lau, B.M.F.; Vucic, D

    2001-07-01

    The airway dimensions for Caucasian males have been scaled by multiplying by factors 0.95 and 0.88 to give those for Chinese males and females, respectively. Employing the most recent data on physical and biological parameters, the radiation doses to the basal and secretory cells due to {alpha} particles from {sup 218}Po and {sup 214}Po, homogeneously distributed in the mucous layer, have been calculated. The emission of {alpha} particles has been simulated by a Monte Carlo method. For both basal and secretory cells, the dose conversion coefficients (DCCs) for physical conditions of sleep, rest, light and heavy exercise, have been obtained for Chinese males and females for unattached progeny, and for attached progeny of diameters 0.02, 0.15, 0.25, 0.30 and 0.50 {mu}m. For basal cells, the coefficients lie in the range 0.69-6.82 mGy/(J s/m{sup 3}) or 8.7-86 mGy/WLM for unattached progeny and in the range 0.045-1.98 mGy/(J s/m{sup 3}) or 0.57-25 mGy/WLM for attached progeny. The corresponding ranges for Caucasian males are 1.27-8.81 mGy/(J s/m{sup 3}) or 16-111 mGy/WLM{sup -1} and 0.05-2.30 mGy/(J s/m{sup 3}) or 0.64-29 mGy/WLM. For secretory cells, the coefficients lie in the range 0.095-16.82 mGy/(J s/m{sup 3}) (1.2-212 mGy/WLM) for unattached progeny and in the range 0.095-6.67 mGy/(J s/m{sup 3}) (1.2-84 mGy/WLM) for attached progeny. The corresponding ranges for Caucasian males are 0.34-21.51 mGy/(J s/m{sup 3}) (4.3-271 mGy/WLM) and 0.1-7.78 mGy/(J s/m{sup 3}) (1.3-98 mGy/WLM). The overall DCCs calculated for a typical home environment are 0.59 and 0.52 mSv/(J s/m{sup 3}) (7.4 and 6.5 mSv/WLM) for Chinese males and females, respectively, which are 80 and 70% of the value, 0.73 mSv/(J s/m{sup 3}) (9.2 mSv/WLM), for Caucasian males.

  8. Radon and progeny sourced dose assessment of spa employees in balneological sites

    International Nuclear Information System (INIS)

    Kemal Uzun, Sefa; Demiroez, Isik

    2016-01-01

    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 Saraykoey 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 R 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 questionnaire 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. (authors)

  9. Biological indicators of exposure to radon

    International Nuclear Information System (INIS)

    Beno, M.

    1998-01-01

    A review is given of recent investigations into mutagenesis and carcinogenesis due to alpha irradiation by the radon progeny. Studies of the occurrence of chromosomal aberrations after alpha irradiation are given particular attention. In the author's opinion, up to now no useful biological indicator of response to high and low doses of alpha particles has been found, including those of radon on the molecular and cellular level. (A.K.)

  10. The protective effect of propolis on damage to lung and blood in rats by inhaled radioactive radon and its progeny

    International Nuclear Information System (INIS)

    Ding Jiansong; Nie Jihua; Tong Jian

    2006-01-01

    Twenty-eight male wistar rats were randomly divided into seven groups, i.e. the radon groups (3), the propolis+radon groups (3) and the control (1). The propolis+radon groups were fed intragastrically with propolis 0.2 g/kg, before exposing them, together with the radon groups, to radon and its progeny with the cumulative dose up to 30, 67 and 111 working level month (WLM), respectively. The levels of SOD (superoxide dismutase) and MDA (Malonic dialdehyde) in blood and lung tissue were determined. The SOD level of in blood and lung tissues of the radon groups decreased significantly and the MDA level increased. The MDA level in lung tissue of the 30 WLM propolis+radon group was significantly higher than the 30 WLM radon group. The SOD level in lung tissue of the 67 WLM propolis+radon group was significantly higher, but the MDA level was significantly lower, than the 67 WLM radon group. Both the SOD and MDA levels in blood and lung tissue of the 111 WLM propolis+radon group were significantly higher than the 111 WLM radon group. In conclusion, the inhalation of radon and its progeny can lead to persistent disturbance of the redox state in rats. Propolis show some protective effects on the redox damage under the experimental conditions. (authors)

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

    Energy Technology Data Exchange (ETDEWEB)

    Winkler-Heil, R.; Hofmann, W. [University of Salzburg, Division of Physics and Biophysics, Department of Materials Research and Physics, Salzburg (Austria); Hussain, M. [University of Salzburg, Division of Physics and Biophysics, Department of Materials Research and Physics, Salzburg (Austria); Higher Education Commission of Pakistan, Islamabad (Pakistan)

    2015-05-15

    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{sup -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. (orig.)

  12. Experimental verification of the attachment theory of radon progeny onto ambient aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Tokonami, Shinji

    2000-01-01

    The attachment theory of radon progeny onto ambient aerosols was experimentally verified with a cascade impactor and a graded screen array at the EML environmental chamber. Monodisperse aerosols in the size range of 70 to 500 nm were generated with Carnauba wax by means of the evaporation-condensation method. The temperature and the relative humidity in the chamber were set at 20 C and 20%, respectively, throughout the entire experiment. When the aerosols were being injected into the chamber, both the number size distribution and the activity-weighted size distribution of attached radon progeny were stable. The activity-weighted size distribution was compared with the attachment rate distribution obtained by measuring the number size distribution with the SMPS and multiplying the size-dependent attachment coefficient. There was a relatively good agreement between the two distributions.

  13. Study on calculation models and distribution rules of the radon concentration and its progenies concentration in blind roadway with forced-exhaust ventilation

    International Nuclear Information System (INIS)

    Ye Yongjun; Wang Liheng; Zhou Xinghuo; Li Xiangyang; Zhong Yongming; Wang Shuyun; Ding Dexin

    2014-01-01

    The forced-exhaust ventilation is an important way to control the concentration of radon and its progenies in long-distance blind driving roadway. It is of great significance for guiding the design of ventilation and radiation protection to study distribution characteristics of the concentration of radon and its progenies in the wind of roadway adopting the forced-exhaust ventilation. Therefore, according to the decay relationship of radon and its progenies, a simplified mathematical calculation model was built, which relates to the radon activity concentration and the potential alpha concentration of radon progenies. The paper also analyzed the sources of radon and its progenies in the limited space of the blind roadway. Then, based on the turbulence mass transfer theory of ventilation air flow, the paper established mathematical calculation models of distribution characteristics of the radon activity concentration and the potential alpha concentration of radon progenies in blind roadway with forced-exhaust ventilation, respectively. Finally, the paper applied the calculation models to a special blind roadway, and discussed the influence of the ventilation air inflow and the radon exhalation rate of rock wall on the distribution of radon concentration and the potential alpha concentration of radon progenies in the roadway. Meanwhile, some protective measurements were put forward to reduce the radiation dose of worker caused by radon and its progenies in the blind roadway. (authors)

  14. Risk assessment of exposure to radon decay products

    Energy Technology Data Exchange (ETDEWEB)

    Monchaux, G

    1999-07-01

    The aim of this project was to assess the risk due to inhalation of radon and its decay products using an horizontal approach across a large scale research programme. The central objective was the assessment of human risk which requires combination of several topics involving a multidisciplinary approach. In the Aerosol Studies Group, progress was achieved in improvement, calibration and automation of experimental techniques for continuous and integrated measurements of the unattached fraction f{sub p}- and equilibrium factor F- values. Measurements were performed to determine the variation of size distributions of unattached and aerosol-associated radon decay products under typical living conditions. All aerosol groups performed controlled chamber studies to understand the basic behaviour of airborne activity concentrations. Measurements were performed to determine neutralisation rates of {sup 218}Po, to understand the cluster growth with residence time and to understand the hygroscopic growth of aerosol particles. In the Modelling Group, the programme RADEP has been developed to calculate the weighted committed equivalent lung dose per unit exposure of radon progeny (H{sub w}/P{sub p}) which implements the ICRP Publication 66 Human Respiratory Tract Model (HRTM). The stochastic deposition model (IDEAL) has been compared with the deposition model used by the HRTM, and the agreement between the two deposition models was excellent. A deterministic radon progeny dosimetry model (RADOS) has been developed. This model includes all bronchial airway generations compared with the HRTM that groups the 16 airway generations into three regions. Initial calculations with RADOS show that the basal and secretory cell doses are slightly smaller compared with that of the HRTM. A sensitivity analysis has been performed that has identified those HRTM model parameters that most affect the Hw/Pp. A stochastic rat deposition model (RALMO) and a clearance model for the rat based on the

  15. Risk assessment of exposure to radon decay products

    International Nuclear Information System (INIS)

    Monchaux, G.

    1999-01-01

    The aim of this project was to assess the risk due to inhalation of radon and its decay products using an horizontal approach across a large scale research programme. The central objective was the assessment of human risk which requires combination of several topics involving a multidisciplinary approach. In the Aerosol Studies Group, progress was achieved in improvement, calibration and automation of experimental techniques for continuous and integrated measurements of the unattached fraction f p - and equilibrium factor F- values. Measurements were performed to determine the variation of size distributions of unattached and aerosol-associated radon decay products under typical living conditions. All aerosol groups performed controlled chamber studies to understand the basic behaviour of airborne activity concentrations. Measurements were performed to determine neutralisation rates of 218 Po, to understand the cluster growth with residence time and to understand the hygroscopic growth of aerosol particles. In the Modelling Group, the programme RADEP has been developed to calculate the weighted committed equivalent lung dose per unit exposure of radon progeny (H w /P p ) which implements the ICRP Publication 66 Human Respiratory Tract Model (HRTM). The stochastic deposition model (IDEAL) has been compared with the deposition model used by the HRTM, and the agreement between the two deposition models was excellent. A deterministic radon progeny dosimetry model (RADOS) has been developed. This model includes all bronchial airway generations compared with the HRTM that groups the 16 airway generations into three regions. Initial calculations with RADOS show that the basal and secretory cell doses are slightly smaller compared with that of the HRTM. A sensitivity analysis has been performed that has identified those HRTM model parameters that most affect the Hw/Pp. A stochastic rat deposition model (RALMO) and a clearance model for the rat based on the HRTM have been

  16. Effect of ventilation on concentrations of indoor radon- and thoron-progeny: Experimental verification of a simple model

    International Nuclear Information System (INIS)

    Sheets, R.W.; Thompson, C.C.

    1993-01-01

    Different models relating the dependence of radon ( 222 Rn)- and thoron ( 220 Rn)-progeny activities on room ventilation rates are presented in the literature. Some of these models predict that, as the rate of ventilation increases, activities of thoron progeny decrease more rapidly than those of radon progeny. Other models predict the opposite trend. In this study alpha activities of the radon progeny, 218 Po, 214 Pb, and 214 Bi, together with the thoron progeny 212 Pb, were measured over periods of several days in two rooms of a closed, heated house. Effective ventilation rates were calculated from measured 214 Pb/ 214 Bi ratios. A simple model in which progeny concentrations decrease by radioactive decay and by dilution with outside air has been used to calculate 212 Pb/ 214 Pb ratios as a function of ventilation rate. Calculated ratios are found to correlate significantly with experimentally-determined ratios (R 2 ∼ 0.5--0.8 at p < 0.005) confirming that, for this house, thoron progeny activities decrease faster than radon progeny activities with increasing rates of ventilation

  17. Exposure to Radon in Dwellings in the Area of Zagreb

    International Nuclear Information System (INIS)

    Lokobauer, N.; Franic, Z.; Petroci, Lj.; Sokolovic, E.; Lokner, V.

    1998-01-01

    Until the 1970s radon and its progeny were regarded as radiation health hazards encountered only in the mining and processing of uranium ore. This notion has dramatically changed as a result of increasing efforts made by many countries to measure radon in dwellings. Since it has been assessed that radon constitutes on average about 53% of the human exposure to natural radiation (UNSCEAR 1993), attention to the problem of exposure to radon and associated health risk has been growing in both developed and developing countries. This paper deals with the investigations of indoor radon activity concentrations at selected dwellings in the area of Zagreb. The fact that concentration of indoor radon depends strongly on radium sources in the soil pointed to the possibility that increased radon levels could be measured in the ground floor dwellings. The measurements of indoor radon performed by Honeywell professional radon monitor in the 30 ground floor dwellings, and at same location in 10 dwellings on higher floors. In order to obtain average daily values, radon activity concentrations were measured throughout 24 hours at each dwelling, over the seasons spring-summer and autumn-winter. In the season spring-summer radon activity concentrations in the ground floor dwellings ranged from 22±5 to 133±12 Bqm -3 (mean value 56±31 Bqm -3 ) and in the season autumn-winter ranged from 22±5 to 311±18 Bqm -3 (mean value 94±64 Bqm -3 ). In the dwellings on higher floors radon activity concentrations in the season spring-summer ranged from 11±3 to 78±9 Bqm -3 (mean value 32±21 Bqm -3 ), and in the season autumn-winter ranged from 30±5 to 137±12 Bqm -3 (mean value 60±32 Bqm -3 ). Average annual radon activity concentration for the 30 investigated ground floor dwellings were 75±45 Bqm -3 , and 46±26 Bqm -3 for the 10 dwellings on higher floors. Investigations performed in the dwellings in the area of Zagreb revealed significant differences in radon levels between the ground

  18. Measurement of unattached radon progeny based in electrostatic deposition method; Medicion de la fraccion no unida a aerosoles de la progenie de {sup 222}Rn mediante un metodo de deposicion electrostatica

    Energy Technology Data Exchange (ETDEWEB)

    Canoba, A C; Lopez, F O

    1999-07-01

    A method for the measurement of unattached radon progeny based on its electrostatic deposition onto wire screens, using only one pump, has been implemented and calibrated. The importance of being able of making use of this method is related with the special radiological significance that has the unattached fraction of the short-lived radon progeny. Because of this, the assessment of exposure could be directly related to dose with far greater accuracy than before. The advantages of this method are its simplicity, even with the tools needed for the sample collection, as well as the measurement instruments used. Also, the suitability of this method is enhanced by the fact that it can effectively be used with a simple measuring procedure such as the Kusnetz method. (author)

  19. Exposures to 222Rn and its progeny derived from implanted 210Po activity

    International Nuclear Information System (INIS)

    Nikezic, D.; Yu, K.N.

    2006-01-01

    The Jacobi room model was applied to study the relative contributions from the unattached and attached fractions to the implanted activity of 210 Po. It was found that under normal conditions, about 85% of the implantation was due to the unattached fraction. Sensitivity analysis was performed to identify the most important factors that influence the deposition and implantation of radon progeny. The main factors affecting the incorporation of 210 Po are the attachment rate, deposition rate of unattached progeny and the surface to volume ratio of the room. The calibration curves, which related the 210 Po activity per unit surface area to the concentrations of 222 Rn and of the radon progeny, were determined as functions of exposure times. The implanted activity is found to distribute close to a lognormal distribution. For an exposure of 20 years, the distribution has a geometric standard deviation of 2.2 and a geometric mean of 0.023Bq/m 2 /(Bq/m 3 ). The last value is considered as the calibration coefficient of the glass response in terms of the implanted 210 Po activity per unit surface area per unit concentration of 222 Rn for an exposure period of 20 years

  20. The effect of natural ventilation on radon and radon progeny levels in houses

    International Nuclear Information System (INIS)

    Cavallo, A.; Gadsby, K.; Reddy, T.A.; Socolow, R.

    1992-01-01

    In contradiction to the widely held assumption that ventilation is ineffective as a means of reducing indoor radon concentrations, experiments in a research house have shown that the basement radon level can be reduced by a factor of 5-10 using only natural ventilation. Measurements of the outdoor-basement pressure differential and the radon entry rate show that this unexpectedly large reduction in indoor radon levels is caused by two complementary physical processes. The first mechanism is the obvious one: dilution. Radon concentrations are lowered by the addition of uncontaminated outdoor air. The second mechanism is less evident: an open basement window reduces basement depressurisation. This decreases the rate at which radon-laden soil gas is drawn into the house. It was also found that the radon entry rate is a linear function of basement depressurisation up to a differential pressure of about 4 Pa, as would be expected for laminar soil gas flow; opening two basement windows approximately doubles the building air exchange rate and reduces the radon entry rate by up to a factor of 5. (author)

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

    International Nuclear Information System (INIS)

    Marsh, J. W.; Bailey, M. R.

    2013-01-01

    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. (authors)

  2. Study of indoor radon, thoron and their progeny concentration levels in the surrounding areas of Mangaldoi, Assam

    International Nuclear Information System (INIS)

    Deka, P.C.; Sarkar, S.; Goswami, T.D.; Sarma, B.K.

    2006-01-01

    Natural sources contribute a significant percentage of radiation towards the total radiation exposure that humans receive. The majority of this natural radiation is harmless to humans in the ambient environment. However, radon, a major component of the natural radiation that humans are exposed to (greater than sixty percent), can pose a threat to the public health when radon gas accumulates in poorly ventilated residential and occupational settings. Measurements of concentration of radon, thoron and their decay products in various indoor environment covering four seasons of a year were carried out using the passive time-integrated method by employing LR-15 type II detectors in plastic twin-chamber dosimeter cups. The estimated indoor radon levels for well ventilated houses varied from a minimum value of 25.2 Bq.m -3 to a maximum of 80J Bq.m -3 with an annual geometric mean of 46.9 Bq.m -3 and that for poorly ventilated houses varied from a minimum value of 46.8 Bq.m -3 to a maximum of 146.8 Bq.m -3 with the annual geometric mean of 82 .2 Bq.m -3 . The thoron levels in well ventilated houses were also varied from a minimum value of 4.9 Bq.m -3 to a maximum of 21.5 Bq.m -3 with an annual geometric mean of 10.5 Bq.m -3 and that for poorly ventilated houses varied from a minimum of 6.3 Bq.m -3 to a maximum value of 29.2 Bq.m -3 with the annual geometric mean of 14.1 Bq.m -3 . Thus it is seen that both radon and thoron levels are higher in poorly ventilated houses than in well-ventilated houses. The ranges of radon and thoron progeny levels for well ventilated houses were 0.10 mWL to 0.58 mWL with an annual geometric mean of 0.21 mWL and 0.01 mWL to 0.06 mWL with an annual geometric mean of 0.03 mWL respectively. Similar variation was also observed in poorly ventilated houses. In poorly ventilated houses, the radon and thoron progeny levels varied between 0.16 mWL and 1.61 mWL with an annual geometric mean of 0.41 mWL and 0.02 to 029 mWL with the annual geometric mean

  3. Levels of radon gas concentration and progeny in homes of Potosi City, Bolivia to 4000 m

    International Nuclear Information System (INIS)

    Mamani M, R.; Claros J, J.; Vasquez A, R.

    2015-10-01

    Full text: In this work the presence of radon gas was determined, which is a radioactive contaminant that comes from underground, able to penetrate the houses. The danger is that when mixed air and when inhaled can cause serious damage to the lungs, for the short life time that has radon and progeny for decay, damaging the pulmonary alveoli and reducing breathing capacity of the habitants, then causing polycythemia in some cases. The study was carried out in homes in the city of Potosi, Bolivia located at 4000 m. The quantification of radon gas and progeny was performed with the equipment Alpha-Zaeller-2 (Az-2), quantification was realized in 6 zones of the city of Potosi, chosen randomly. In each zone were carried out measurements in 40 homes (2 rooms more permanent), both day and night, for a period of 3 days in two different seasons and with concentrations of average humidity of 20, 50 and 80%. The values obtained for each period vary depending on the season and 30 to 50% of the allowable values given by the EPA and Who for housing. (Author)

  4. Measurement of indoor radon-thoron and their progeny levels in dwellings and radon concentrations in ground water of Hassan city, Karnataka, India

    International Nuclear Information System (INIS)

    Srinivasa, E.; Rangaswamy, D.R.; Sannappa, J.

    2014-01-01

    The indoor radon and thoron concentrations in dwellings of Hassan city have been measured by using LR-115 type-Il Solid State Nuclear Tracks Detectors (SSNTDs). Measurements were carried in summer season from March to May-2013. The radon and thoron activity concentration in the corresponding dwellings has been found to vary from 7.4 to 45.7 Bqm -3 and 5.4 to 34.9 Bqm -3 with a median of 23.59±11 Bqm -3 and 14.47±8 Bqm -3 respectively. The overall average radon concentrations are found to be less than the lower reference level of 200 Bq m -3 of the International Commission on Radiological Protection. The annual effective dose received due to radon and its progeny by the inhabitants in the dwellings under study has also been calculated which found to vary from 0.320 ±0.4 to 1.86 ±1.1 mSv y -1 with an average value of 0.957±0.8 mSv -1 . The obtained results are much lower than the upper reference level of 10 mSv y -1 (ICRP 2007). Radon in bore well water at different locations of Hassan city was determined using the emanometry technique and exposure dose from ingestion of drinking water was estimated. The radon concentration in ground water was found to vary from 19.49 to 60.74 Bq l -1 with an average value of 47.16±14Bq l -1 . From this study it is evident that, the recorded ground water radon concentration values are higher than MCL of 11 Bq l -1 proposed by USEPA. The total dose due to inhalation and ingestion of 222 Rn in ground water ranges from 0.053 mSv y -1 to 0.165mSv y -1 with an average value of 0.127±0.038mSv y -1 . (author)

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  6. Variation of indoor radon progeny concentration and its role in dose assessment

    International Nuclear Information System (INIS)

    Singh, Manmohan; Singh, Kulwant; Singh, Surinder; Papp, Z.

    2008-01-01

    Instantaneous measurements of equilibrium equivalent concentration of radon (EEC Rn ) were taken over a period of 1 year in 2004 in a typical house at Amritsar city, located in the northwest part of India. A method based on absolute beta counting subsequent to grab aerosol sampling was used. During that year, EEC Rn varied between 1.56 Bq m -3 and 22.77 Bq m -3 with average value of 8.76 Bq m -3 . EEC Rn decreased with the transition from winter to summer and vice versa, having a negative correlation with outdoor temperature. The use of mechanical ventilation, under normal living conditions during summer, caused an extra decrease in the concentrations. The variations with temperature and mechanical ventilation are discussed. Some major issues related to the uncertainties in dose calculations caused by the lack of knowledge of equilibrium factor and ignoring the effect of life style on the radon and its progeny concentrations are discussed

  7. Underground measurements of aerosol in radon and thoron progeny activity distributions

    International Nuclear Information System (INIS)

    Khan, A.; Bandi, F.; Phillips, C.R.; Duport, P.

    1990-01-01

    Aerosol and activity distributions of 218 Polonium, 214 Lead, 214 Bismuth, and 212 Lead were determined in two different underground mining environments by means of an optimized time-delay counting scheme and diffusion batteries. In one environment, diesel equipment was operating; and in the other, electrically powered equipment. The two environments differed significantly in total aerosol concentration. In the diesel environment, in particular, aerosol concentrations were unsteady, and fluctuated with vehicular traffic and mining activities. As measured by radon progeny disequilibrium, the age of the air ranged from about 25 to 60 minutes. Thoron working levels were of the same order as radon working levels. In this paper, comparisons are made between the aerosol and activity size distributions in both the diesel and electric mine

  8. Measurement of the size distributions of radon progeny in indoor air

    International Nuclear Information System (INIS)

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

    1990-01-01

    A major problem in evaluating the health risk posed by airborne radon progeny in indoor atmospheres is the lack of available information on the activity-weighted size distributions that occur in the domestic environment. With an automated, semicontinuous, graded screen array system, we made a series of measurements of activity-weighted size distributions in several houses in the northeastern United States. Measurements were made in an unoccupied house, in which human aerosol-generating activities were simulated. The time evolution of the aerosol size distribution was measured in each situation. Results of these measurements are presented

  9. Submicron-sized aerosol and radon progeny measurements in an uranium mine

    International Nuclear Information System (INIS)

    Boulaud, D.; Chouard, J.C.

    1992-01-01

    Submicron-sized aerosol was studied in an uranium mine using an Electrical Aerosol Analyzer and a Differential Mobility Particle Sizer. In addition radon progeny particle size distributions were measured using a prototype instrument developed by us (SDI 2000). With cascade impactor the number weighted mean electrical mobility diameters and the geometric standard deviations ranged respectively from 0.05 to 0.1 μm and 1.8 to 2. The gross alpha activity weighted mean thermodynamic diameters ranged typically from 0.1 to 0.2 μm. 6 refs., 3 figs

  10. Validation of the abbreviated Radon Progeny Integrating Sampling Unit (RPISU) method for Mesa County, Colorado

    International Nuclear Information System (INIS)

    Langner, G.H. Jr.

    1987-06-01

    The US Department of Energy (DOE) Office of Remedial Action and Waste Technology established the Technical Measurements Center at the DOE Grand Junction, Colorado, Projects Office to standardize, calibrate, and compare measurements made in support of DOE remedial action programs. Indoor radon-daughter concentration measurements are made to determine whether a structure is in need of remedial action. The Technical Measurements Center conducted this study to validate an abbreviated Radon Progeny Integrated Sampling Unit (RPISU) method of making indoor radon-daughter measurements to determine whether a structure has a radon-daughter concentration (RDC) below the levels specified in various program standards. The Technical Measurements Center established a criterion against which RDC measurements made using the RPISU sampling method are evaluated to determine if sampling can be terminated or whether further measurements are required. This abbreviated RPISU criterion was tested against 317 actual sets of RPISU data from measurements made over an eight-year period in Mesa County, Colorado. The data from each location were tested against a standard that was assumed to be the same as the actual annual average RDC from that location. At only two locations was the criterion found to fail. Using the abbreviated RPISU method, only 0.6% of locations sampled can be expected to be falsely indicated as having annual average RDC levels below a given standard

  11. An Alpha spectrometer for measuring radon daughter individual activity concentration; Spettrometro Alfa per la misura delle concentrazioni individuali in attivita' della progenie del radon

    Energy Technology Data Exchange (ETDEWEB)

    Berico, M.; Formignani, M. [ENEA, Div. Protezione dell' Uomo e degli Ecosistemi, Centro Ricerche E. Clementel, Bologna (Italy); Mariotti, F. [Bologna Univ., Bologna (Italy). Dipt. di Fisica

    2001-07-01

    In the frame of the program of the Institute for Radiation Protection of ENEA, related to the evaluation of dose from radon and thoron progeny, an alpha spectrometer for the continuous air monitoring (CAM type) of radon and thoron has been realized. The constructive characteristics of the device are here presented together with energy and efficiency calibration. The device allows, by means of a screen type diffusion battery and a filter, to determinate the single radioactivity of each radionuclide of the progeny selecting them in relation to their diffusive behaviour (dichotomous particle size selection). The three-count filter method has been employed to measure the concentrations of {sup 218}Po, {sup 214}Pb and {sup 214}Bi in air. Radon and thoron effective doses using a dosimetric, instead of an epidemiologic approach, will be then evaluated. [Italian] Presso l'Istituto per la Radioprotezione, nell'ambito del programma di valutazione di dose da radon e' stato progettato e realizzato uno spettrometro alfa per il monitoraggio continuo in aria (CAM) della progenie del radon e del toron. Le caratteristiche costruttive dello strumento permettono, tramite l'utilizzo di batterie a diffusione a reti, di determinare l'attivita' individuale della progenie per diverse dimensioni granulometriche in particolare per la frazione attaccata e non al particolato amosferico con un taglio granulometrico di qualche nanometro. E' stato inoltre applicato un metodo spettrometrico a tre conteggi per il calcolo delle concentrazioni individuali della progenie del radon, {sup 218}Po, {sup 214}Pb and {sup 214}Bi, effettuando un conteggio alfa di {sup 218}Po e due conteggi alfa di {sup 214}Po. Tale informazione consentira' una valutazione della dose di radon utilizzando il modello dosimetrico in alternativa a quello epidemiologico.

  12. Controlling exposure to radon, France, December 2006

    International Nuclear Information System (INIS)

    Godet, J.L.; Perrin, M.L.; Dechaux, E.; Pineau, C.

    2007-01-01

    Controlling exposure to radon, France, December 2006 Exposure to radon, along with medical exposure, is the leading source of the French population exposure to ionizing radiation. Radon is a confirmed cause of lung cancer in man (classified in group I by the international Agency for research on Cancer (I.A.R.C.)). According to available estimates, the numbers of lung cancers attributable to radon exposure in France are far fewer than those caused by tobacco. However, according to a recent European study, around 9% of lung cancers in Europe may be caused by radon. Thus, due to the number of people exposed, radon has become a public health issue which calls for action, considering that exposure can be significantly reduced by implementing measures which are often simple. Since 2002, the Nuclear Safety Authority (Asn) has proceeded in implementing a new regulatory framework for the risk management related to the presence of radon in public places. The new system is now fully operational. In addition, based on the initiatives adopted by the government in June 2004 in the context of the National Health and Environment Plan (P.N.S.E.), the Asn drew up a plan in 2005, in collaboration with the Ministry for Urban Planning and Construction, to coordinate the actions of various national bodies involved in this field. This three-pronged strategy is as follows: - Creation of a new risk management policy related to the presence of radon in existing homes and in new buildings; - Supporting and controlling the implementation of regulations for managing radon related risks in public places; - Improvement and dissemination of knowledge on radon exposure and its related risks. (author)

  13. Study on seasonal variation of indoor radon, thoron and their progeny levels in Hassan District of Karnataka, India

    International Nuclear Information System (INIS)

    Srinivasa, E.; Rangswamy, D.R.; Sannappa, J.

    2015-01-01

    Radon, thoron and their progeny concentrations have been measured in different types of buildings at different locations for different seasons in Hassan city using time-integrated passive radon dosimeters containing LR-115 Type II solid state nuclear track detector exposed for four seasons of 3 months each covering a period of one year from October 2012 to September 2013. The radon and thoron activity concentration in summer season in the corresponding dwellings has been found to vary from 7.4 to 45.7 Bq m -3 and 5.4 to 34.9 Bqm -3 with a median of 23.59±11 Bqm -3 and 1447±8 Bq -3 respectively. The radon progeny concentrations varies from 0.4 to 4.1 mWL with an average value of 1.83±1 mWL, while thoron progeny concentrations vary from 0.3 to 3.2 mWL with an average value of 1.12±0.7 mWL respectively. The annual effective dose received due to radon, thoron and its progeny by the inhabitants in the dwellings under study has also been calculated which is found to vary from 0.320±0.4 to 1.860 ±1.1 mSv y -1 with an average value of 0.9576 ± 0.8 mSv y -1 . In general, the level of radon-thoron was observed highest in winter and lowest in summer. A detail analysis of radon and thoron distribution in different houses with seasonal variation is presented in this paper. From this study it is observed that, bathrooms and kitchens have significantly higher radon concentrations as compared to other rooms in the dwellings. (author)

  14. Internal microdosimetry of inhaled radon progeny in bronchial airways: advantages and limitations

    International Nuclear Information System (INIS)

    Hofmann, Werner; Fakir, Hatim; Pihet, Pascal

    2007-01-01

    The objective of the present study was to identify advantages and limitations of the application of microdosimetric concepts for inhaled radon progeny activities in the lungs. The methods employed for this analysis were a recently developed Monte- Carlo microdosimetry code for the calculation of energy deposition in bronchial target cells and the Probability Per Unit Track Length (PPUTL) model, which relates these microdosimetric parameters to cellular radiation effects. The major advantages of internal microdosimetry of radon progeny in bronchial airways are: (i) quantitative characterisation of non-uniform dose distributions and identification of target sites with enhanced carcinogenic potential, (ii) quantification of low doses of alpha particles by the number of cells hit and the dose received by those cells, (iii) illustration of the random variations of cellular doses by specific energy distributions and (iv) establishment of a direct link to cellular radiobiological effects. At present, a major limitation of microdosimetry is the extrapolation of the response of individual cells to the resulting tissue response, which is still not fully explored. (authors)

  15. Inversion of the Jacobi-Porstendorfer room model for the radon progeny

    International Nuclear Information System (INIS)

    Thomas, J.; Jilek, K.; Brabec, M.

    2010-01-01

    The Jacobi-Porstendoerfer (J-P) room model describes the behaviour of radon progeny in the atmosphere of a room. It distinguishes between free and attached radon progeny in air. It has been successfully used without substantial changes for nearly 40 years. There have been several attempts to invert the model approximately to determine the parameters describing the physical processes. Here, an exact solution is aimed at as an algebraic inversion of the system of six linear equations for the five unknown physical parameters k, X, R, q f , q a of the room model. Two strong linear dependencies in this system, unfortunately do not allow to obtain a general solution (especially not for the ventilation coefficient k), but only a parameterized one or for reduced sets of unknown parameters. More, the impossibility to eliminate one of the two linear dependencies and the departures of the measured concentrations forces to solve a set of allowed combinations of equations of the algebraic system and to accept its mean values (therefore with variances) as a result of the algebraic inversion. These results are in agreement with results of the least squares method as well as of a sophisticated modern statistical approach. The algebraic approach provides, of course, a lot of analytical relations to study the mutual dependencies between the model parameters and the measurable quantities. (authors)

  16. Interaction of radon Exposure and cigarette smoking on cells

    International Nuclear Information System (INIS)

    Zhu, Maoxiang; Wei, Han; Yang, Zhihua; Pan, Xiujie; Cao, Zhenshan

    2008-01-01

    Full text: Environmental radon and its progenies is important lung carcinogen both in occupational underground miners and in the general population. Exposure to radon often occurs combined with smoking, another most important lung carcinogen. The join biological effects of alpha- particle radiation and cigarette smoke condense (CSC) were investigated here in order to provide experimental base for medical protection from lung cancer inducing by joint exposure of radon and smoking. Immortalized human bronchial epithelial cells (BEP2D) were divided into 5 groups, namely normal control group (NC), alpha particles irradiation group (0.25 Gy,α), CSC administration group (1μg/ml, CSC), CSC administration (1μg/ml) before (CSC + α) and after (α + CSC) alpha particles irradiation (0.25 Gy) group. On the 35 th passage after treated by alpha particles irradiation and CSC singly or jointly, only α + CSC cells showed malignant transformation characteristics, representing anchor growing independently, losing contact inhibition, and cell cycle disordering, whereas, there were no distinct difference between cells of other groups and normal cells. Moreover, comparison to the groups treated alone with alpha particles radiation or CSC administration, in the groups of joint exposure to alpha particles radiation and CSC treatment, cell survival fractions markedly decreased, intracellular ROS levels, frequencies of comet cell generation significantly increase, and could found that cell survival fractions of group CSC administration after α particle radiation was significantly higher than that of group CSC administration before alpha particles irradiation, suggesting that interaction of radon and smoking associated with their exposure sequence. In summary, interaction of radon and smoking was synergistic effect, and which was impacted by the order of exposure. (author)

  17. An intercomparison between gross α counting and gross β counting for grab-sampling determination of airborne radon progeny and thoron progeny

    International Nuclear Information System (INIS)

    Papp, Z.

    2006-01-01

    The instantaneous values of the airborne activity concentrations of radon progeny and thoron progeny have been determined 34 times in a closed and windowless room in a cellar using two independent grab-sampling methods in order to compare the performance of the methods. The activity concentration of radon ( 222 Rn) was also measured and it varied between 200 and 650 Bq m -3 . Two samples of radon and thoron progeny were collected simultaneously from roughly the same air volume by filtering. For the first method, the isotopes were collected on membrane filter and gross α counting was applied over several successive time intervals. This method was a slightly improved version of the methods that are applied generally for this reason for decades. For the second method, the isotopes were collected on glass-fibre filter and gross β counts were registered over several time intervals. This other method was developed a few years ago and the above series of measurements was the first opportunity to make an intercomparison between it and another similar method based on α counting. Individual radon progeny and thoron progeny activity concentrations (for the isotopes 218 Po, 214 Pb, 214 Bi and 212 Pb) were evaluated by both methods. The detailed investigation of the results showed that the systematic deviation of the methods is small but significant and isotope-dependent. The weighted averages of the β/α activity concentration ratios for 218 Po, 214 Pb, 214 Bi, EEDC 222 (Equilibrium-Equivalent Decay-product Concentration of radon progeny) and 212 Pb were 0.99±0.03, 0.90±0.02, 1.03±0.02, 0.96±0.02 and 0.80±0.03, respectively. The source of the systematic deviation is probably the inaccurate knowledge of the counting efficiencies mainly in the case of the α-counting method. A significant random-type difference between the results obtained with the two methods has also been revealed. For example, the β/α ratio for EEDC 222 varied between 0.81±0.01 and 1.22±0

  18. Radon dosimetry: a review of radon and radon daughter exposure conditions in dwellings and other structures

    International Nuclear Information System (INIS)

    Ryan, M.T.; Goldsmith, W.A.; Poston, J.W.; Haywood, F.F.; Witherspoon, J.P.

    1983-07-01

    Within the past few years several situations have been brought to light which indicate an increased radiation exposure of certain segments of the general population caused by human activities. The most widely publicized activities are those associated with the mining and milling of uranium in the western United States, the phosphate industry in Florida, and those potential problems represented by former Manhattan Engineer District sites. One of the primary problems involves exposure to radon and radon daughters which are released from large waste piles or, in some cases, evolve from backfill and construction materials used in homes, schools, and other buildings. This report presents a review of the available data on radon and radon daughter concentrations in dwellings and other structures. The primary objectives were to compile and tabulate pertinent radon exposure data and to prepare a statistical summary of the data which will be useful in the prediction of normal levels of radon and radon daughter concentrations in these structures. In addition, other parameters associated with radon exposure conditions are presented and discussed

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

    International Nuclear Information System (INIS)

    Quindos Poncela, L.; Fernandez Navarro, P.; Sainz Fernandez, C.; Gomez 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 222 Rn 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). (authors)

  20. Concentration of Radon Progeny in Air by Alpha Spectrometry Measurement; Medida de los descendientes del radon en aire por Espectrometria Alfa

    Energy Technology Data Exchange (ETDEWEB)

    Acena, M L; Crespo, M T

    1989-07-01

    The concentration of radon progeny in air has been determined by alpha spectrometry measurement of 214 Po and 318 Po. A known volume of air was passed through a filter, then the alpha activity was directly measured on this filter. (Author) 15 refs.

  1. Occupational and environmental exposures to radon: A perspective for mitigators

    International Nuclear Information System (INIS)

    Sanchez, D.C.; Messing, M.; Saum, D.

    1989-01-01

    This paper compares normal environmental and occupational exposures to radon and radon decay products for the occupational group, including radon mitigators and diagnosticians. Occupational exposures to radon and radon decay products and the associated high incidence of radiation-induced lung cancer form the basis for current concern for limiting exposures to radon. While it is now known that radon is a ubiquitous environmental pollutant and estimates exist as to what this means in terms of cancer risk to the general population, similar estimates are not available for radon mitigators and diagnosticians

  2. Radon Sources and Associated Risk in terms of Exposure and Dose

    Directory of Open Access Journals (Sweden)

    Efstratios Gregory Vogiannis

    2015-01-01

    Full Text Available Radon concern the international scientific community from early 20th century. Initially as radium emanation, almost the second half of the century as severe harmful to human health. Initial brilliant period of use as medicine, followed by a period of intense concern for its health effects. Primary target groups surveyed were miners early in Europe later in U.S. There is now compelling evidence that radon and its progeny can cause lung cancer. 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. Indoor Radon and its short-lived progeny attached on aerosol particles or free compose an air mixture that carry a significant energy amount (PAEC. Exposure on PAEC and dose delivered reviewed in detail. Special attention was paid to the case of water workers because lack of adequate data. Radon risk assessment and current legislation regulates dose from radon and its progeny, also were reviewed.

  3. Exposure to unusually high indoor radon levels

    International Nuclear Information System (INIS)

    Rasheed, F.N.

    1993-01-01

    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 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

  4. Risk assessment of exposure to radon concentration in indoor atmosphere and drinking water of Shimoga city, Karnataka, India

    International Nuclear Information System (INIS)

    Rangaswamy, D.R.; Sannappa, J.; Srinivasa, E.

    2016-01-01

    The exposure of population to natural sources of radiation has become an important issue in terms of radiological protection. The major contribution of dose from natural radiation in normal background regions arises due to inhalation of alpha-emitting radon and thoron, and their progenies, which are ubiquitous in both indoor and outdoor environs. The aim of the present study is to measure indoor radon, thoron and their progeny levels in the dwellings of Shimoga city and radon concentration in drinking water and to estimate the annual effective dose. The indoor concentration of radon, thoron and their progeny was measured using Solid-State Nuclear Track Detectors (SSNTDs) based twin chamber dosimeter cups. The 222 Rn concentration in drinking water was estimated by the Emanometry technique

  5. Measurment of radon, thoron and their progeny in indoor environment of Mohali, Punjab, Northern India, using pinhole dosimeters

    Directory of Open Access Journals (Sweden)

    Mehta Vimal

    2016-01-01

    Full Text Available The health hazards of radon and its decay products above certain levels are well known. However, for any preventive measures to be taken, we have to be aware of radon levels of that particular area. Measurement of radon and its decay products in indoor environments is an important aspect of assessing indoor air quality and health conditions associated with it. Keeping this in mind, measurements of radon, thoron and their progeny concentrations were carried out in Mohali, Northern India, using pinhole-based twin cup dosimeters. Radon exhalation rates of soil samples in the dwellings/areas were measured via an active technique of a continuous radon monitor. The indoor radon concentration in Mohali varied from 15.03 ± 0.61 Bq/m3 to 39.21 ± 1.46 Bq/m3 with an average of 26.95 Bq/m3 ,while thoron concentration in the same dwellings varied from 9.62 ± 0.54 Bq/m3 to 52.84 ± 2.77 Bq/m3 with an average of 31.09 Bq/m3. Radon progeny levels in dwellings under study varied from 1.63 to 4.24 mWL, with an average of 2.94 mWL, while thoron progeny levels varied from 0.26 to 1.43 mWL , with an average of 0.84 mWL. The annual dose received by the inhabitants of dwellings under study varied from 0.78 to 2.36 mSv, with an average of 1.61 mSv. The in situ gamma dose rate varied from 0.12 to 0.32 mSv/h.

  6. Unattached fraction and the aerosol size distribution of the radon progeny in a natural cave and mine atmospheres

    International Nuclear Information System (INIS)

    Butterweck, G.; Porstendoerfer, J.; Reineking, A.; Kesten, J.

    1992-01-01

    Measurements of the activity size distribution of aerosol-attached radon progeny and the amount of unattached radon daughters have been performed in mine atmospheres and a tourist cave. During working hours a large number (10 5 -10 6 cm -3 ) of aerosol particles is generated in mines, mainly by diesel engines. The activity size distribution of these aerosol particles has smaller median diameters (AMAD about 200 nm) than the aged aerosol existing in the mine during non-working hours (AMAD about 350 nm). Strictly correlated to the aerosol concentration, the unattached fraction of the radon progeny, f p , in the tourist cave (3000 particles per cm 3 ) is higher (f p = 0.1) than in mines (f p 0.01) during working hours. This yields 1.4-2.5 times higher radiation dose conversion factors in the natural cave than in mines under working conditions. (author)

  7. Particle size distribution of the radon progeny and ambient aerosols in the Underground Tourist Route “Liczyrzepa” Mine in Kowary Adit

    Directory of Open Access Journals (Sweden)

    Wołoszczuk Katarzyna

    2018-01-01

    Full Text Available Central Laboratory for Radiological Protection, in cooperation with Central Mining Institute performed measurements of radon concentration in air, potential alpha energy concentration (PAEC, particle size distribution of the radon progeny and ambient aerosols in the Underground Tourist-Educational Route “Liczyrzepa” Mine in Kowary Adit. A research study was developed to investigate the appropriate dose conversion factors for short-lived radon progeny. The particle size distribution of radon progeny was determined using Radon Progeny Particle Size Spectrometer (RPPSS. The device allows to receive the distribution of PAEC in the particle size range from 0.6 nm to 2494 nm, based on their activity measured on 8 stages composed of impaction plates or diffusion screens. The measurements of the ambient airborne particle size distribution were performed in the range from a few nanometres to about 20 micrometres using Aerodynamic Particle Sizer (APS spectrometer and the Scanning Mobility Particle Sizer Spectrometer (SMPS.

  8. Short- and long-term variability of radon progeny concentration in dwellings in the Czech Republic.

    Science.gov (United States)

    Slezáková, M; Navrátilová Rovenská, K; Tomásek, L; Holecek, J

    2013-03-01

    In this paper, repeated measurements of radon progeny concentration in dwellings in the Czech Republic are described. Two distinct data sets are available: one based on present measurements in 170 selected dwellings in the Central Bohemian Pluton with a primary measurement carried out in the 1990s and the other based on 1920 annual measurements in 960 single-family houses in the Czech Republic in 1992 and repeatedly in 1993. The analysis of variance model with random effects is applied to data to evaluate the variability of measurements. The calculated variability attributable to repeated measurements is compared with results from other countries. In epidemiological studies, ignoring the variability of measurements may lead to biased estimates of risk of lung cancer.

  9. Measurement of radon progeny concentrations in air by alpha-particle spectrometey

    International Nuclear Information System (INIS)

    Kerr, G.D.

    1975-07-01

    A technique is presented for measuring air concentrations of the short-lived progeny of radon-222 by the use of alpha spectrometry. In this technique, the concentration of RaA, RaB, and RaC are calculated from one integral count of the RaA and two integral counts of the RaC' alpha-particle activity collected on a filter with an air sampling device. The influence of air sampling and counting intervals of time on the accuracy of the calculated concentrations is discussed in the report. A computer program is presented for use with this technique. It is written in the BASIC language. The program will calculate the air concentrations of RaA, RaB, and RaC, and will estimate the accuracy in these calculated concentrations. (U.S.)

  10. Effects of aerosol polydispersity on theoretical calculations of unattached fractions of radon progeny

    International Nuclear Information System (INIS)

    Bandi, F.; Khan, A.; Phillips, C.R.

    1987-01-01

    Theoretical calculations of unattached fractions of radon progeny require prediction of an attachment coefficient. Average attachment coefficients for aerosols of various count median diameters, CMD, and geometric standard deviations, σ/sub g/, are calculated using four different theories. These theories are: (1) the kinetic theory, (2) the diffusion theory, (3) the hybrid theory and (4) the kinetic-diffusion theory. Comparisons of the various calculated attachment coefficients are made and the implications of using either the kinetic or the diffusion theory to calculate unattached fractions for aerosols of various CMD and σg are discussed. Significant errors may arise in use of either the kinetic theory or the diffusion theory. Large and unacceptable errors arise in calculating unattached fractions of a polydisperse aerosol by characterizing the aerosol as monodisperse. Unattached fractions of RaA are calculated for two mine aerosols and a room aerosol

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

    Science.gov (United States)

    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. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Unattached fraction and the size distribution of the radon progeny in indoor air

    International Nuclear Information System (INIS)

    Yamasaki, K.; Shimo, M.

    1992-01-01

    The size-distribution of the aerosol-attached radon progeny and the unattached (cluster) fraction were measured by using a low pressure cascade impactor and a single wire screen in a building of the nuclear facility. The radon concentration at the condition of ventilation 'ON' was about 50 Bq m -3 , but it increased exponentially after ventilation 'OFF' and reached to the saturated concentration of about 600 Bq m -3 . At the condition of low aerosol concentration without additional aerosol, the activity median aerodynamic diameter, the geometric standard deviation and the unattached fraction were, respectively, 0.4 μm, 2.7-2.9 and 0.3-0.5. On the other hand, at the condition of high aerosol concentration with burning a mosquito coil, these were, 0.4 μm, 2.1 and 0.02-0.03. These yield 2.5 times higher radiation dose conversion factors at the low aerosol condition than the high aerosol condition. (author)

  13. SARAD EQF 3020 - A new microsystem based monitoring system for the continuous measurement of radon and the attached and unattached fraction of the radon progeny

    International Nuclear Information System (INIS)

    Streil, T.; Holfeld, G.; Oeser, V.; Feddersen, C.; Schoenefeld, K.

    1996-01-01

    Due to the large differences in the dose factors for radon and radon daughters it's recommended to measure both, but monitors for the continuous and simultaneous measurement of radon and radon progeny concentrations are too expensive to be widely used if they are built from individual components. Integrating detector, readout electronics, memory and an A/D converter on a single chip offers far lower prices at least if this silicon microsystem can be produced in large quantities. It is known that dRAM cells of commercial available memories are sensitive to alpha particles, but even if one accepts unstable operating conditions (Ucc 2 . Further development with special PMOS-transistors in a floating n-well as sensor cells has resulted in an alpha particle spectrometric microsystem with an effective sensor array of 40 mm 2 . Alternative for higher resolution we developed PiN -structures with more than 100 mm 2 sensor area with integrated preamplification

  14. Estimation of equilibrium factors of radon and its progeny using SSNTDs in the various dwellings of Hyderabad, Andhra Pradesh, India

    International Nuclear Information System (INIS)

    Yadagiri Reddy, P.; Rama Reddy, K.; Sreenath Reddy, M.

    2013-01-01

    In the estimation of effective dose in the indoor environment due to Radon and its progeny the equilibrium factor (F) plays a significant role. It is the radioactive equilibrium between radon and its short-lived decay products. Generally in the dose estimation is made taking the equilibrium factor 0.4 (UNSCEAR value) for the radon and its progeny. But in practice the concentration of radon and its progeny vary significantly with local environmental conditions and time, subsequently the equilibrium factor F also changes and hence affects the effective dose estimation of a particular dwelling. Therefore the UNSCEAR F value does not reflect the actual effective doses. Therefore, the present study is carried out to estimate the equilibrium factors in different types of dwellings in the urban Hyderabad using SSNTDs. It is found that, the equilibrium factors in the urban Hyderabad vary from 0.01 to 0.71 with an average 0.32 ± 0.23. The average F values of urban Hyderabad relatively lower than Indian average and global average. The reasons for the lower equilibrium factor values in the study area have been discussed in this paper. (author)

  15. Indoor Radon Exposure in Italian Schools

    Directory of Open Access Journals (Sweden)

    Antonio Azara

    2018-04-01

    Full Text Available Background: The aim of the study was to assess radon concentration in schoolrooms in a city located in the midwest of Italy. Methods: A two-phase environmental study was carried out in 19 school buildings of 16 primary, secondary, and tertiary schools. Results: Median (interquartile range—IQR indoor radon concentration in schoolrooms was 91.6 (45.0–140.3 Bq/m3. The highest (median 952.8 Bq/m3 radon concentration was found in one (3.6% classroom, located in a building of a primary school whose median concentration was 185 Bq/m3. Radon concentration was significantly correlated with the number of students and teachers, foundation wall construction material, and with the absence of underground floors. A geopedological survey was performed close to the building with highest radon level, showing the presence of granite and tonalithic granodiorite in the soil. Conclusions: Radon levels should be routinely assessed where individuals live or work. Schools are susceptible targets, because of childhood stay and the long daily stay of occupants. Low-cost interventions, such as implementation of natural air ventilation and school maintenance, can reduce radon levels, limiting individual exposure.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    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

  18. Health effects and risks of radon exposure

    International Nuclear Information System (INIS)

    Cross, F.T.

    1990-01-01

    In view of the current widespread concern about the risks associated with indoor radon exposures, this paper explores the evidence on risk from human epidemiology studies, particularly in reference to EPA's 4-pCi/L action level value and from animal studies. While the EPA 4-pCi/L level has no legal force and is not a standard per se, it is becoming a de facto standard as several states are considering the level in pending legislation. Although risk can also be related to radiation dose from radon exposure, this perspective on risk is not treated in this chapter

  19. Determination of Lung-to-Blood Absorption Rates for Lead and Bismuth which are Appropriate for Radon Progeny

    International Nuclear Information System (INIS)

    Marsh, J.W.; Birchall, A.

    1999-01-01

    The ICRP Publication 66 Human Respiratory Tract Model (HRTM) treats clearance as a competitive process between absorption into blood and particle transport to the gastrointestinal tract and lymphatics. The ICRP recommends default absorption rates for lead and bismuth in ICRP Publication 71 but states that the values are not appropriate for short-lived radon progeny. This paper describes an evaluation of published data from volunteer experiments to estimate the absorption half-times of lead and bismuth that are appropriate for short-lived radon progeny. The absorption half-time for lead was determined to be 10±2 h, based on 212 Pb lung and blood retention data from several studies. The absorption half-time for bismuth was estimated to be about 13 h, based on 212 Bi urinary excretion data from one experiment and the ICRP biokinetic model for bismuth as a decay product of lead. (author)

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

    International Nuclear Information System (INIS)

    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

  1. The influence of the cigarette smoke pollution and ventilation rate on alpha-activities per unit volume due to radon and its progeny

    International Nuclear Information System (INIS)

    Misdaq, M.A.; Flata, K.

    2003-01-01

    Alpha and beta activities per unit volume air due to radon, thoron and their decay products were evaluated in the air of various cafe rooms polluted by cigarette smoke. Both CR-39 and LR-115 type II solid state nuclear track detectors (SSNTD) were used. Equilibrium factors between radon and its progeny and thoron and its daughters have been evaluated in the air of the studied cafe rooms. The committed equivalent doses due to short-lived radon decay products were determined in different regions of the respiratory tract of non-smoker members of the public. The influence of cigarette smoke pollution, ventilation rate and exposure time on committed equivalent dose in the respiratory systems of non-smokers was investigated. Committed equivalent doses ranged from 1.15x10 -11 -2.7x10 -7 Sv.y -1 /h of exposure in the extrathoracic region and from 0.8x10 -12 -1.7x10 -8 Sv.y -1 /h of exposure in the thoracic region of the respiratory tract of non-smokers

  2. Radon in the indoor environment

    International Nuclear Information System (INIS)

    Vanmarcke, H.

    1998-01-01

    A precise retrospective assessment of long-term radon exposures in dwellings is essential for estimating lung-cancer risks. The objectives of this research are (1) to investigate the deposition of radon progeny in the human respiratory tract by means of direct measurements as a function of aerosol conditions, (2) to assess the radon concentrations in buildings retrospectively with volume traps

  3. Radon Progenies as a Source of Gross Alpha-beta Activities in Drinking Water in Vinaninkarena, Antsirabe-Madagascar

    International Nuclear Information System (INIS)

    Raoelina Andriambololona; Rabesiranana, N.; Rasolonirina, M.; Rakotomanga, H.

    2004-01-01

    The village of Vinaninkarena, Antsirabe, Madagascar is located in a high radioactivity area. With the aim of assessing the health impact of radioactivity pollution, a survey was conducted around an abandoned radium mining. Waters from 24 sampling points, including 5 wells and 13 springs were sampled. The water radioactivity was measured using a portable Triathler LSC, model 425-034 from Hidex Turku. Each sample is counted more than 3 times: less than 2h after sampling, 4h to few days and more than 3 weeks after when 226 Ra attains equilibrium with 222 Rn and its short-lived daughters. Combination of water non miscible, radon extractive LS cocktail and water miscible one is used to reveal contribution of radium, radon and its short lived progenies to the gross alpha-beta activities. Maximum activity values found are : 3.6±0.3 Bq.L -1 for 226 Ra, 554±9 Bq.L -1 for the excess of radon, and 408±8 Bq.L -1 for the excess of radon progenies. Based on these data, a daily consumption of 2 L of these waters by a standard person would produce an annual 226 Ra ingestion well above the annual intake limit for 226 Ra. Moreover, the increasing gross alpha-beta activity resulting from radon progenies raises the issue of health effects. The potential for rapid spring-to-mouth delivery, which is frequent in rural area, may expose the water consumer to the short-lived alpha particle emitters.

  4. Numerical modelling of local deposition patients, activity distributions and cellular hit probabilities of inhaled radon progenies in human airways

    International Nuclear Information System (INIS)

    Farkas, A.; Balashazy, I.; Szoeke, I.

    2003-01-01

    The general objective of our research is modelling the biophysical processes of the effects of inhaled radon progenies. This effort is related to the rejection or support of the linear no threshold (LNT) dose-effect hypothesis, which seems to be one of the most challenging tasks of current radiation protection. Our approximation and results may also serve as a useful tool for lung cancer models. In this study, deposition patterns, activity distributions and alpha-hit probabilities of inhaled radon progenies in the large airways of the human tracheobronchial tree are computed. The airflow fields and related particle deposition patterns strongly depend on the shape of airway geometry and breathing pattern. Computed deposition patterns of attached an unattached radon progenies are strongly inhomogeneous creating hot spots at the carinal regions and downstream of the inner sides of the daughter airways. The results suggest that in the vicinity of the carinal regions the multiple hit probabilities are quite high even at low average doses and increase exponentially in the low-dose range. Thus, even the so-called low doses may present high doses for large clusters of cells. The cell transformation probabilities are much higher in these regions and this phenomenon cannot be modeled with average burdens. (authors)

  5. Exposures to radon in homes in Adana

    International Nuclear Information System (INIS)

    Yegingil, Z.

    1990-01-01

    Radon escaping from soil into homes appears to present the single greatest source of radiation exposure that most people will ever face. The use of solid state nuclear tracks detectors (SSNTD) is one of the most convenient techniques to assess the average radiation levels of alpha activities in the environment. By using CR-39 and LR-115 detectors long term alpha activities have been investigated to be noticeable the concentrations of natural radionuclides and Rn-222 exhalation rate under different environmental conditions in Adana. The radon distributions have been measured in soils an in single houses and apartment buildings in various floors in the summer and winter time. The seasonal variation of the radon concentration measured by CR-39 and LR-115 displayed a correlation. (author). 25 refs, 2 tabs

  6. Instruments to measure radon activity concentration or exposure to radon. Interlaboratory comparison 2011

    International Nuclear Information System (INIS)

    Foerster, Elisabeth; Beck, Thomas; Buchroeder, Helmut; Doering, Joachim; Schmidt, Volkmar

    2011-10-01

    According to the Directive 96/29/EURATOM the monitoring of occupational radiation exposures shall base on individual measurements carried out by an approved dosimetric service. Pursuant to the European Directive an approved dosimetric service is a body responsible for the calibration, reading or interpretation of individual monitoring devices.., whose capacity to act in this respect is recognized by the competent authorities. This concept will also be applied to radon services issuing passive radon measurement devices. Passive radon measurement devices 1 using solid state nuclear track detectors or electrets are recommended for individual monitoring of exposures to radon. German regulations lay down that radon measuring devices are appropriate for purposes of occupational radiation monitoring if the devices are issued by recognized radon measurement services, and the measurement service submits devices of the same type issued for radon monitoring to regular intercomparisons conducted by BfS. A radon measuring service is recognized by the competent authority if it proves its organizational and technical competence, e. g. by accreditation. These regulations have been introduced in the area of occupational radiation exposures. Nevertheless, it is recommended that radon measuring services which carry out radon measurements in other areas (e.g. dwellings) should subject themselves to these measures voluntarily. The interlaboratory comparisons comprise the organization, exposure, and evaluation of measurements of radon activity concentration or exposure to radon. The comparisons only concern radon-222; radon-220 is not in the scope. Radon services being interested can get further information from the website www.bfs.de/de/ion/radon/fachinfomessung/vergleichspruefungen.html and from the European Information System on Proficiency Testing Schemes (eptis) available in the internet. (orig.)

  7. Levels of radon gas concentration and progeny in homes of Potosi City, Bolivia to 4000 m; Niveles de concentracion de gas radon y progenie en viviendas de la Ciudad de Potosi, Bolivia a 4000 msnm

    Energy Technology Data Exchange (ETDEWEB)

    Mamani M, R. [Universidad Autonoma Tomas Frias, Carrera de Fisica, Av. del maestro s/n, Edif. Central Potosi, Villa Imperial de Potosi (Bolivia, Plurinational State of); Claros J, J. [Universidad Autonoma Tomas Frias, Facultad de Minas Potosi, Centro de Investigacion, Av. Serrudo y Arce s/n, Villa Imperial de Potosi (Bolivia, Plurinational State of); Vasquez A, R., E-mail: raulm2k13@hotmail.com [Instituto Boliviano de Biologia de Altura, Calle Hoyos 953, La Paz (Bolivia, Plurinational State of)

    2015-10-15

    Full text: In this work the presence of radon gas was determined, which is a radioactive contaminant that comes from underground, able to penetrate the houses. The danger is that when mixed air and when inhaled can cause serious damage to the lungs, for the short life time that has radon and progeny for decay, damaging the pulmonary alveoli and reducing breathing capacity of the habitants, then causing polycythemia in some cases. The study was carried out in homes in the city of Potosi, Bolivia located at 4000 m. The quantification of radon gas and progeny was performed with the equipment Alpha-Zaeller-2 (Az-2), quantification was realized in 6 zones of the city of Potosi, chosen randomly. In each zone were carried out measurements in 40 homes (2 rooms more permanent), both day and night, for a period of 3 days in two different seasons and with concentrations of average humidity of 20, 50 and 80%. The values obtained for each period vary depending on the season and 30 to 50% of the allowable values given by the EPA and Who for housing. (Author)

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

    International Nuclear Information System (INIS)

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

    1991-05-01

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

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

    Science.gov (United States)

    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

  10. Instruments to measure radon-222 activity concentration or exposure to radon-222. Intercomparison 2014

    International Nuclear Information System (INIS)

    Foerster, Elisabeth; Beck, Thomas; Buchroeder, Helmut; Doering, Joachim; Schmidt, Volkmar

    2014-10-01

    According to the Directive 96/29/EURATOM the monitoring of occupational radiation exposures shall base on individual measurements carried out by an approved dosimetric service. Pursuant to the European Directive an approved dosimetric service is a body responsible for the calibration, reading or interpretation of individual monitoring devices.., whose capacity to act in this respect is recognized by the competent authorities. This concept will also be applied to radon services issuing passive radon measurement devices. Passive radon measurement devices 1 using solid state nuclear track detectors or electrets are recommended for individual monitoring of exposures to radon. German regulations lay down that radon measuring devices are appropriate for purposes of occupational radiation monitoring if the devices are issued by recognized radon measurement services, and the measurement service submits devices of the same type issued for radon monitoring to regular intercomparisons conducted by the Bundesamt fuer Strahlenschutz (BfS). A radon measuring service is recognized by the competent authority if it proves its organisational and technical competence, e. g. by accreditation. These regulations have been introduced in the area of occupational radiation exposures. Nevertheless, it is recommended that radon measuring services which carry out radon measurements in other areas (e.g. dwellings) should subject themselves to these measures voluntarily. The interlaboratory comparisons comprise the organization, exposure, and evaluation of measurements of radon activity concentration or exposure to radon. The comparisons only concern radon-222; radon-220 is not in the scope. Radon services being interested can get further information from the European Information System on Proficiency Testing Schemes (EPTIS) and from the BfS websites.

  11. Developing a method for the retrospective estimation of radon exposure from in vivo measurements of 210Pb activity in bone

    International Nuclear Information System (INIS)

    McKenzie, R.J.; Johnston, P.N.

    1999-01-01

    Radon is a naturally occurring radioactive gas which has been linked to lung cancer in occupationally exposed uranium mine workers. Where monitoring of an individual's exposure to radon and radon progeny has not occurred or is incomplete, it may be possible to determine this exposure retrospectively by the measurement of the long lived decay product 210 Pb which accumulates in the bones of exposed individuals. This paper describes a method being developed at the whole body monitor (WBM) facility of the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) to estimate the time integrated exposure to radon over a period of up to several decades from the in vivo measurements of 210 Pb activity in the knee of human subjects. Initial work has concentrated on characterising the WBM facility for this work using artificial bone phantoms. This project will serve as a test of the feasibility of the method before undertaking further studies on human subjects

  12. Changes of indoor aerosol characteristics and their associated variation on the dose conversion factor due to radon progeny inhalation

    International Nuclear Information System (INIS)

    Tokonami, Shinji; Ishikawa, Tetsuo; Yonehara, Hidenori; Yamada, Yuji; Matsuzawa, Takao; Iimoto, Takeshi

    2003-01-01

    Since the dose conversion factor (hereafter called DCF) due to radon progeny inhalation is strongly dominated by aerosol characteristics in the environment, it is important to understand the air quality for accurate dose assessment. Thus temporal variations on aerosol concentration, its particle size and its related airborne radioactivities were continuously measured in an actual indoor environment with a relatively high radon concentration. The following human activities were added during the observation period: air-conditioning, removal of aerosol with an air cleaner and ventilation. DCFs based on these activities were evaluated with the latest International Commission of Radiological Protection (ICRP) respiratory tract model and were compared among them. Consequently, the present study has shown that operation of air cleaner enhanced the DCF critically because the unattached fraction increased significantly due to removal of aerosols. (author)

  13. The effect of increase in humidity on the size and activity distributions of radon progeny laden aerosols from hydrocarbon combustion

    International Nuclear Information System (INIS)

    Khan, Atika; Phillips, C.R.

    1988-01-01

    The effects of a humidity increase on the distributions of aerosol size and activity for hydrocarbon combustion aerosols laden with radon progeny were determined. Pre-humidification aerosol conditions were 20 0 C and 35% RH. Post-humidification aerosol conditions were 37 0 C and 100% RH, intended to simulate conditions in the human respiratory tract. Using kerosene combustion aerosols, a growth factor of 1.3 ± 0.2 (standard deviation) was found for both the aerosol median diameter and the activity median diameter. (author)

  14. Radon exposure during treatment in some thermal spa centers in Greece

    International Nuclear Information System (INIS)

    Nikolopoulos, D.; Louizi, A.; Serefoglou, A.; Georgiou, E.; Vogiannis, E.; Halvadakis, C.

    2004-01-01

    Radon ( 222 Rn) present in the spa facilities has been identified as an agent of additional radiation burden both for bathers and the working personnel. Although some researchers have been concentrated on the health impact of radon activity transient increases due to water flow of domestically used water, limited work has been reported on this effect in spa facilities. The aim of this work was to study the exposure both of bathers and working personnel due to water flow under working conditions in some thermal spas in Greece. The spas studied were built at two locations in Greece; Lesvos Island and the city of Loutra- Edipsou. The study was performed between 1999 and 2003. Measurements involved determination of radon concentration in the waters of the thermal spas, monitoring of radon and short-lived decay product activity (both in attached and unattached form) and coarse particles (> 500 nm). Water radon concentration was measured by Alpha Guard PQ2000Pro of Genitron GmbH equipped with an appropriate unit (Aquakit). Indoor radon activity was monitored by Alpha Guard PQ2000Pro and EQF3023 of Sarad GmbH which was also used for monitoring of radon short-lived decay product activity. Coarse particle concentration measurements were performed by a GRIMM 1.104 Portable Dust Monitor. Measurements indoors were performed in the treatment room and in the reception room, if existing, under working conditions. Several procedures for bath filling and pouring out of the treatment room, during the measurements, were studied. Radon concentrations of thermal waters were found to lie in the range 1 Bq.L -1 and 304 Bq.L -1 . Some of these concentrations may be considered as elevated. Elevated (about 2-6 kBq.m -3 ) indoor radon concentrations were measured in the treatment rooms of the spas of Polichnitos, Eftalou and Loutra Edipsou. This found to be in accordance to the high radon potential of these spas, as detected out of the measurements of their thermal waters. Concentration

  15. Annual effective dose due to residential radon progeny in Sweden: Evaluations based on current risk projections models and on risk estimates from a nation-wide Swedish epidemiological study

    Energy Technology Data Exchange (ETDEWEB)

    Doi, M [National Inst. of Radiological Sciences, Chiba (Japan); Lagarde, F [Karolinska Inst., Stockholm (Sweden). Inst. of Environmental Medicine; Falk, R; Swedjemark, G A [Swedish Radiation Protection Inst., Stockholm (Sweden)

    1996-12-01

    Effective dose per unit radon progeny exposure to Swedish population in 1992 is estimated by the risk projection model based on the Swedish epidemiological study of radon and lung cancer. The resulting values range from 1.29 - 3.00 mSv/WLM and 2.58 - 5.99 mSv/WLM, respectively. Assuming a radon concentration of 100 Bq/m{sup 3}, an equilibrium factor of 0.4 and an occupancy factor of 0.6 in Swedish houses, the annual effective dose for the Swedish population is estimated to be 0.43 - 1.98 mSv/year, which should be compared to the value of 1.9 mSv/year, according to the UNSCEAR 1993 report. 27 refs, tabs, figs.

  16. Annual effective dose due to residential radon progeny in Sweden: Evaluations based on current risk projections models and on risk estimates from a nation-wide Swedish epidemiological study

    International Nuclear Information System (INIS)

    Doi, M.; Lagarde, F.

    1996-12-01

    Effective dose per unit radon progeny exposure to Swedish population in 1992 is estimated by the risk projection model based on the Swedish epidemiological study of radon and lung cancer. The resulting values range from 1.29 - 3.00 mSv/WLM and 2.58 - 5.99 mSv/WLM, respectively. Assuming a radon concentration of 100 Bq/m 3 , an equilibrium factor of 0.4 and an occupancy factor of 0.6 in Swedish houses, the annual effective dose for the Swedish population is estimated to be 0.43 - 1.98 mSv/year, which should be compared to the value of 1.9 mSv/year, according to the UNSCEAR 1993 report. 27 refs, tabs, figs

  17. Radiation exposure due to radon and radon daughters

    International Nuclear Information System (INIS)

    Ullmann, W.

    1976-01-01

    Underground miners working over long periods of time in mines with a high content of radon and radon daughters belong to that group of occupationally exposed persons who are subject to the greatest somatic risk, with values especially high if the permissible dose limits are exceeded. Follwing an overview of the permissible limits currently in use for radon and radon daughters as well as the results of examinations performed in nationally-owned underground mining of the G.D.R., considerations are presented on the measuring quantities requisite for statistical, control and safety measurements in this field. Finally, conclusions are drawn concerning the measuring procedures and instruments to be employed for practical work. (author)

  18. Study on indoor radon exposure and its effect on human health

    International Nuclear Information System (INIS)

    Lu Xinwei

    2005-01-01

    Radon and its daughters relate to people health. Radon widely exists in the nature. The paper discusses the source, exposure and activity level of indoor radon, systematically analyzes the hazards and dose-response of residential radon exposure, and at last indicates the concrete method of controlling residential radon concentration. By interdicting radon pollution source and ventilation might effectively reduce indoor radon concentration and improve environmental air quality. (authors)

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

    Czech Academy of Sciences Publication Activity Database

    Janik, M.; Ploc, Ondřej; Fiederle, M.; Proc, S.; Kavasi, N.

    2016-01-01

    Roč. 107, JAN (2016), s. 220-224 ISSN 0969-8043 Institutional support: RVO:61389005 Keywords : Radon * Thoron * Timepix * calibration Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.128, year: 2016

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

    Energy Technology Data Exchange (ETDEWEB)

    Guilmette, R.A.; Laurer, G.R. [New York Univ. Inst. of Environmental Medicine, Tuxedo, NY (United States); Lambert, W.E.; Gilliland, F.D. [Univ. of New Mexico, Albuquerque, NM (United States)] [and others

    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.

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

    International Nuclear Information System (INIS)

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

    1995-01-01

    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 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 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 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 210 Pb in the heads of former uranium miners has been accomplished

  2. Long-term determination of airborne concentrations of unattached and attached radon progeny using stacked LR 115 detector with multi-step etching

    International Nuclear Information System (INIS)

    Nikezic, D.; Yu, K.N.

    2010-01-01

    We developed the theoretical basis for long-term determination of airborne concentrations of unattached and attached radon progeny. The work was separated into two parts. First, we showed that (stacked and multiply etched) LR 115 detectors could be used to determine airborne concentrations of the short-lived radon progeny, 218 Po and 214 Bi. The equilibrium factor F between radon and its progeny could then be determined through the use of the reduced equilibrium factor F red . The airborne concentrations of 214 Pb could then be determined. Second, we developed a method based on the airborne concentrations of 218 Po, 214 Pb and 214 Bi to determine the parameters of the Jacobi room model, viz., the ventilation rate λ v , aerosol attachment rate λ a , deposition rate of unattached progeny λ d u and the deposition rate of attached progeny λ d u . With these parameters, the unattached fraction f p of the potential alpha energy concentration could also be determined. Knowledge of f p , together with F, would enable more accurate determination of the effective dose in the human lung.

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

    Science.gov (United States)

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

    2014-01-01

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

  4. Exposure to radon/radon decay products in waterworks

    International Nuclear Information System (INIS)

    Schmitz, J.; Nickels, R.M.; Fritsche, R.

    2000-01-01

    Since 1989 survey measurements at workplaces possibly burdened by radon and its decay products have been performed in the Federal Republic of Germany. Referring to the basic standards for radiation protection issued by Euratom and the recommendations of the German Advisory Committee on Radiological Protection (SSK), workplaces were first examined in underground facilities, i.e. in production and visitors mines and show caves, by in situ measurements and date recordings. Subsequently, all balneotherapeutic facilities in the Federal Republic of Germany were measured. Currently, we are finishing a survey of drinking water supply systems in the southwest of Germany. Some 100 drinking water supply systems with more than 1200 operating stations such as well houses, conditioning plants, reservoirs, pumping station etc. were measured with instant working level meters, passive dosemeters and for gamma exposure. Various aspects were considered in selecting the facilities, e.g. the number of employees, size of services area, hydrogeological conditions and a uniform distribution over the state area was schieved. A very important part in the investigation was the inquiry into the time spent by employees at each work station. In these 100 water works, some 750 persons are employed and the average yearly working time at the operating stations was approx. 180 hours. The statistical interpretation based on these measurements allows a reliable extrapolation to the expected numbers of workplaces in water supply which exceed the recommended 'normal' limit of 2,000 h x 0.1 WL. At a mean residence time at the operating stations of about one month per year, the upper limit of the 'normal range' is equal to 1 WL. Approx. 15% of the operating stations were found to have higher values. Combining complex water works out of their operating stations, statistically speaking, 10% of the water works exceed the 1 WL limit. Thus, in our case, some 80 employees are found in the group of radiation

  5. Strategy for the reduction of radon exposure in Norway

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-05-15

    Elevated indoor radon concentrations are a more extensive problem in Norway than in many other countries. It has been estimated that indoor radon causes approximately 300 deaths from lung cancer each year in Norway. On average, avoiding lung cancer increases life expectancy by 14 to 18 years. Radon is a radioactive noble gas formed continually is a decay product from uranium. Uranium is a natural constituent existing in varying concentrations in bedrock, minerals and soils. For this reason, both the soil air and groundwater contain radon. Radon in buildings normally originates from the soil air in the underlying ground. Indoor air pressure is often low, so that radon-containing air from the surrounding ground gets sucked in through cracks in the building foundations. Elevated indoor radon concentrations can be due to household water drawn from groundwater wells, and radon gas can also be emitted from building materials such as certain types of stone or concrete containing high levels of natural radioactivity. Norway, Sweden and Finland are among the the countries in the world with the highest average indoor radon concentrations. Geological conditions and the cool climate pose a big challenge, but the radon problem can be solved in a cost-effective way. Radon is the most common cause of lung cancer after active smoking. At a radon concentration of 100 Bq/m3, which is not far from the estimated average for Norwegian housing, the risks of dying of radon-induced lung cancer before the age of 75 are 0.1 % for non-smokers and 2 % for smokers, respectively. Many buildings in Norway have radon levels that exceed this. The most important health impact of radon exposure is the increased risk of lung cancer. This increase in risk is assumed to be linear in relation to radon concentration (i.e., the risk is 10 times higher at 1000 Bq/m3 compared to 100 Bq/m3). The risk also increases linearly with exposure time, i.e. there is a tenfold greater risk of contracting lung cancer

  6. Strategy for the reduction of radon exposure in Norway

    International Nuclear Information System (INIS)

    2010-05-01

    Elevated indoor radon concentrations are a more extensive problem in Norway than in many other countries. It has been estimated that indoor radon causes approximately 300 deaths from lung cancer each year in Norway. On average, avoiding lung cancer increases life expectancy by 14 to 18 years. Radon is a radioactive noble gas formed continually is a decay product from uranium. Uranium is a natural constituent existing in varying concentrations in bedrock, minerals and soils. For this reason, both the soil air and groundwater contain radon. Radon in buildings normally originates from the soil air in the underlying ground. Indoor air pressure is often low, so that radon-containing air from the surrounding ground gets sucked in through cracks in the building foundations. Elevated indoor radon concentrations can be due to household water drawn from groundwater wells, and radon gas can also be emitted from building materials such as certain types of stone or concrete containing high levels of natural radioactivity. Norway, Sweden and Finland are among the the countries in the world with the highest average indoor radon concentrations. Geological conditions and the cool climate pose a big challenge, but the radon problem can be solved in a cost-effective way. Radon is the most common cause of lung cancer after active smoking. At a radon concentration of 100 Bq/m3, which is not far from the estimated average for Norwegian housing, the risks of dying of radon-induced lung cancer before the age of 75 are 0.1 % for non-smokers and 2 % for smokers, respectively. Many buildings in Norway have radon levels that exceed this. The most important health impact of radon exposure is the increased risk of lung cancer. This increase in risk is assumed to be linear in relation to radon concentration (i.e., the risk is 10 times higher at 1000 Bq/m3 compared to 100 Bq/m3). The risk also increases linearly with exposure time, i.e. there is a tenfold greater risk of contracting lung cancer

  7. Regulatory Strategy to Control Radon Exposure in Pakistan

    International Nuclear Information System (INIS)

    Younus, Irfan; Cho, Kun Woo

    2012-01-01

    Pakistan Nuclear Regulatory Authority (PNRA) was established in 2001 with one of the objectives to ensure the protection of workers, general public and the environment from the harmful effects of naturally occurring and artificially produced ionizing radiations by formulating and implementing the effective regulations. Radon is a naturally occurring odorless, colorless, tasteless, imperceptible to senses and chemically inert radioactive gas which is produced continuously from the natural decay of U-238, U-235 and Th-232 in most soils, rocks and water all over the earth. High levels of radon in the soil and rock are primarily responsible for indoor radon problems. Therefore when inhaled with air, there much probability that radon decay products will stay and decay in the lungs. If stayed in the lungs, the radiation may damage the cells causing lung cancer. Hence the radon problems have been taken seriously in most of the developed countries of the world. Radon reference levels for dwellings and workplaces have been set and the general public has been made alert of radon through newspapers and electronic media. In Pakistan, neither publicity campaign nor radon measurement and control programmes have been started countrywide. Rather small individual efforts for the sake of interest have been done to investigate the radon in some specific area or institution. This paper presents the regulatory strategy to control radon exposure for the sake of radiation protection of public and workers in Pakistan

  8. A method for determining an indicator of effective dose calculation due to inhalation of Radon and its progeny from in vivo measurements; Um metodo para determinar um indicador para calcular dose efetiva devida a inalacao de Radonio e seus descendentes utilizando medicoes in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Estrada, Julio Jose da Silva

    1994-07-01

    Direct measurement of the absolved dose to lung tissue from inhalation of radon and its progeny is not possible and must be calculated using dosimetric models, taking into consideration the several parameters upon which the dose calculation depends. To asses the dose due to inhalation of radon and its progeny, it is necessary to estimate the cumulative exposure. Historically, this has been done using WLM values estimated with measurements of radon concentration in air. The radon concentration in air varies significantly, however, in space with time, and the exposed individual is also constantly moving around. This makes it almost impossible to obtain a precise estimate of an individual's inhalation exposure. This work describes a pilot study to calculate lung dose from the deposition of radon progeny, via estimates of cumulative exposure derived from in vivo measurements of {sup 210} Pb, in subjects exposed to above-average radon and its progeny concentrations in their home environments. The measurements were performed in a whole body counter. With this technique, the exposed individuals become, in affect, their own samplers and dosimeters and the estimate of cumulative exposure is not affected by the variation of the atmospheric concentration of radon and its progeny in time and space. Forty individuals identified as living in homes with radon levels ranging from about 740 Bq/m{sup 3} to 150.000 Bq/m{sup 3} were measured. Also, additional 34 measurements were made on personnel from NYUMC/NIEM who live in a residential area surrounding the laboratory in which the levels of radon have been shown to be at below average values. To realize these measurements a methodology was developed to determine the subject's background, using a head phantom made with a cubic plastic container containing known amounts of potassium and calcium dissolved in four liters of water. The effective doses calculated from the in vivo measurements are compared to effective doses estimated, for

  9. A method for determining an indicator of effective dose calculation due to inhalation of Radon and its progeny from in vivo measurements; Um metodo para determinar um indicador para calcular dose efetiva devida a inalacao de Radonio e seus descendentes utilizando medicoes in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Estrada, Julio Jose da Silva

    1994-07-01

    Direct measurement of the absolved dose to lung tissue from inhalation of radon and its progeny is not possible and must be calculated using dosimetric models, taking into consideration the several parameters upon which the dose calculation depends. To asses the dose due to inhalation of radon and its progeny, it is necessary to estimate the cumulative exposure. Historically, this has been done using WLM values estimated with measurements of radon concentration in air. The radon concentration in air varies significantly, however, in space with time, and the exposed individual is also constantly moving around. This makes it almost impossible to obtain a precise estimate of an individual's inhalation exposure. This work describes a pilot study to calculate lung dose from the deposition of radon progeny, via estimates of cumulative exposure derived from in vivo measurements of {sup 210} Pb, in subjects exposed to above-average radon and its progeny concentrations in their home environments. The measurements were performed in a whole body counter. With this technique, the exposed individuals become, in affect, their own samplers and dosimeters and the estimate of cumulative exposure is not affected by the variation of the atmospheric concentration of radon and its progeny in time and space. Forty individuals identified as living in homes with radon levels ranging from about 740 Bq/m{sup 3} to 150.000 Bq/m{sup 3} were measured. Also, additional 34 measurements were made on personnel from NYUMC/NIEM who live in a residential area surrounding the laboratory in which the levels of radon have been shown to be at below average values. To realize these measurements a methodology was developed to determine the subject's background, using a head phantom made with a cubic plastic container containing known amounts of potassium and calcium dissolved in four liters of water. The effective doses calculated from the in vivo measurements are compared to effective doses

  10. Risk of Lung Cancer and Indoor Radon Exposure in France

    International Nuclear Information System (INIS)

    Baysson, H.; Tirmarche, M.; Tymen, G.; Ducloy, F.; Laurier, D.

    2004-01-01

    It is well established that radon exposure increases risks of lung cancer among underground miners. to estimate the lung cancer risk linked to indoor radon exposure, a hospital based case-control study was carried out in France, With a focus on precise reconstruction of past indoor radon exposure over the 30 years preceding the lung cancer diagnosis. The investigation rook place from 1992 to 1998 in four regions of France: Auvergne, Brittany, Languedoc and Limousin. During face-to-face interviews a standardized questionnaire was used to ascertain demographic characteristics, information on active and passive smoking, occupational exposure, medical history as well as extensive details on residential history. Radon concentrations were measured in the dwellings where subjects had lived at least one year during the 5-30 year period before interview. Measurements of radon concentrations were performed during a 6-month period, using two Kodalpha LR 115 detectors, one in the living room and one in the bedroom. The time-weighted average (TWA) radon concentration for a subject during the 5-30 year period before interview was based on radon concentrations over all addresses occupied by the subject weighted by the number of years spent at each address. For the time intervals without available measurements, we imputed the region-specific arithmetic average of radon concentrations for measured addresses of control subjects. Lung cancer risk was examined in relation to indoor radon exposure after adjustment for age, sex, region, cigarette smoking and occupational exposure. The estimated relative a risk per 100 Bq/m''3 was 1.04, at the borderline of statistical significance (95 percent Confidence Interval: 0.99, 1..1). These results are in agreement with results from other indoor radon case-control studies and with extrapolations from underground miners studies. (Author) 31 refs

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

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    Abu-Jarad, F. E-mail: falah.abujarad@aramco.com; Fazal-ur-Rehman

    2003-07-01

    Radon gas was allowed to accumulate in its radium source and then injected into a 36 m{sup 3} test room, resulting in an initial radon concentration of 15 kBq m{sup -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{sup 2}-10{sup 5} particles cm{sup -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, {sup 210}Po (T{sub 1/2}=138 days). This isotope is separated from the short-lived progeny by {sup 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 {sup 210}Po on the same filter papers measured in the year 2000 were studied. The results of the {sup 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 {sup 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.

  13. Po-210 excretion and radon exposure

    International Nuclear Information System (INIS)

    Breuer, F.; Clemente, G.F.

    1979-01-01

    A mathematical model is given to describe the metabolism of the 210 Po introduced into the systemic compartiments of the human body. The model has been based on the experimental data referred to the 210 Pb- 210 Po intake, excretion and body burden of members of the general italian population. The model fits also very well the experimental data of 210 Pb- 210 Po intake and excretion reported by other authors. The retention function of 210 Po in total body, soft tissue and bone has been evaluated together with the urinary excretion function and the absorbed fraction by ingestion. The model is very valuable to evaluate the lung exposure to Radon decay products on the basis of the 210 Pb- 210 Po urinary excretions

  14. Use of static and ac field techniques for measuring mobility and charge lifetimes of radon progeny with a simple device

    International Nuclear Information System (INIS)

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

    1998-01-01

    A simple device, based on a modification of the scintillation cell, has been developed for the measurement of radon daughter mobility and charge lifetimes by employing AC and static electric fields. It has a central electrode coated with ZnS and the scintillations are recorded by a PMT unit. The coating is made on the wire, instead of on the inner walls, to improve the relative response of the device with respect to the zero field situation. Radon is drawn into the cell by evacuation techniques. Theoretical formulae, relating the observed count rates to the system parameters and progeny mobilities and charge lifetimes, have been derived under zero field, static and AC field situations. Measurements indicate that the device has very low leak rate (T 1/2 ∼38 days) and the initial environment if maintained for long time. Results of experiments carried out with static and AC fields in most air yielded 218 Po mobilities (1.89 cm 2 /V/s) and charge lifetimes (0.08s) are comparable to those reported in the literature. This demonstrates the feasibility of this technique for future studies with different trace gases. A major advantage of this device as opposed to the conventional spectrometric methods is its simplicity. (author)

  15. Investigation of radon, thoron, and their progeny near the earth's surface. Final report, 1 January 1994 - 31 December 1997

    International Nuclear Information System (INIS)

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

    1998-01-01

    This is the final report for DOE Grant DE-FG03-94ER6178, covering a performance period of 1 January 1994 through 31 December 1997. The DOE award amount for this period was $547,495. The objective of the project as stated in its proposal was open-quotes to improve our understanding of the physical processes controlling the concentration of radon, thoron, and their progeny in the atmospheric environment.close quotes The original project was directed at developing underlying science that would help with evaluation of the health hazard from indoor radon in the United States and implementation of corrective measures that might be employed to reduce the health hazard. As priorities within the Office of Health and Environment (OHER) changed, and the radon research program was phased out, emphasis of the project was shifted somewhat to be also relevant to other interests of the OHER, namely global pollution and climate change and pollution resulting from energy production. This final report is brief, since by reference it can direct the reader to the comprehensive research publications that have been generated by the project. In section 2, we summarize the main accomplishments of the project and reference the primary publications. There were seven students who received support from the project and their names are listed in section 3. One of these students (Fred Yarger, Ph.D. candidate) continues to work on research initiated through this project. No post-docs received support from the project, although one of the co-principal investigators (Dr. Piotr Wasiolek) received the majority of his salary from the project. The project also provided part-time support for a laboratory manager (Dr. Maryla Wasiolek). Section 4 lists chronologically the reports and publications resulting from the project (references 1 through 12), and the Appendix provides abstracts of major publications and reports

  16. Glass implanted 210Po as a method of determination of long term exposure to radon: First experiments in Israel

    International Nuclear Information System (INIS)

    Haquin, G.; Lang, B.; Even, O.; Asael, Y.; Shamai, Y.; Margaliot, M.; Shirav, M.

    2002-01-01

    Radon gas ( 222 Rn) is known to be the major contributor of the total exposure of the population to ionizing radiation. Retrospective assessment techniques have been developed to estimate long term exposures to ( 222 Rn and its progeny in epidemiological studies. Measurements of implanted 210 Po on glass panes surfaces characterize room radon concentration or habitant characterization.Various methods for retrospective radon measurement are described in the literature. The surface trap method is based on the 210 Po implanted on glass or other vitreous objects, measured using solid-state nuclear track detectors (SSNTD). The volume trap method is based on measurements of 210 Po in spongy, porous materials ( 210 Po volume traps). Other approach is in-vivo measurements of 210 Pb in the human skeleton. The present study uses the surface trap retrospective technique for the first time in Israel, coupled with an approach to estimate the 210 Po concentration in glasses exposed to 222 Rn using alpha spectrometry

  17. QA Programme for Radon and its Short-Lived Progeny Measuring Instruments in NRPI Prague

    Czech Academy of Sciences Publication Activity Database

    Jílek, K.; Thomas, J.; Brabec, Marek

    2008-01-01

    Roč. 130, č. 1 (2008), s. 43-47 ISSN 0144-8420 Grant - others:GA SÚJB(CZ) JC_11/2006 Institutional research plan: CEZ:AV0Z10300504 Keywords : calibration * quality assurance * radon daughter products * uncertainty estimation Subject RIV: DI - Air Pollution ; Quality Impact factor: 0.951, year: 2008

  18. High radon exposure in a Brazilian underground coal mine

    International Nuclear Information System (INIS)

    Veiga, L H S; Melo, V; Koifman, S; Amaral, E C S

    2004-01-01

    The main source of radiation exposure in most underground mining operations is radon and radon decay products. The situation of radon exposure in underground mining in Brazil is still unknown, since there has been no national regulation regarding this exposure. A preliminary radiological survey in non-uranium mines in Brazil indicated that an underground coal mine in the south of Brazil had high radon concentration and needed to be better evaluated. This paper intends to present an assessment of radon and radon decay product exposure in the underground environment of this coal mining industry and to estimate the annual exposure to the workers. As a product of this assessment, it was found that average radon concentrations at all sampling campaign and excavation sites were above the action level range for workplaces of 500-1500 Bq m -3 recommended by the International Commission on Radiological Protection-ICRP 65. The average effective dose estimated for the workers was almost 30 times higher than the world average dose for coal miners

  19. Radon Research Program, FY 1992

    International Nuclear Information System (INIS)

    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

  20. Inversion of the Jacobi-Porstendörfer Room Model for the Radon Progeny

    Czech Academy of Sciences Publication Activity Database

    Thomas, J.; Jílek, K.; Brabec, Marek

    2010-01-01

    Roč. 55, č. 4 (2010), s. 433-437 ISSN 0029-5922 Institutional research plan: CEZ:AV0Z10300504 Keywords : Jacobi room model * inversion and invariants of the model * unattached radon daughters * attachment rate * deposition rate Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 0.321, year: 2010 http://www.nukleonika.pl/www/back/full/vol55_2010/v55n4p433f.pdf

  1. The measurement of activity-weighted size distributions of radon progeny: methods and laboratory intercomparison studies

    International Nuclear Information System (INIS)

    Hopke, P.K.; Strydom, R.; Ramamurthi, M.; Knutson, E.O.; Tu, K.W.; Scofield, P.; Holub, R.F.; Cheng, Y.S.; Su, Y.F.; Winklmayr, W.

    1992-01-01

    Over the past 5 y, there have been significant improvements in measurement of activity-weighted size distributions of airborne radon decay products. The modification of screen diffusion batteries to incorporate multiple screens of differing mesh number, called graded screen arrays, have permitted improved size resolution below 10 nm such that the size distributions can now be determined down to molecular sized activities (0.5 nm). In order to ascertain the utility and reliability of such systems, several intercomparison tests have been performed in a 2.4 m3 radon chamber in which particles of varying size have been produced by introducing SO2 and H2O along with the radon to the chamber. In April 1988, intercomparison studies were performed between direct measurements of the activity-weighted size distributions as measured by graded screen arrays and an indirect measurement of the distribution obtained by measuring the number size distribution with a differential mobility analyzer and multiplying by the theoretical attachment rate. Good agreement was obtained in these measurements. A second set of intercomparison studies among a number of groups with graded screen array systems was made in April 1989 with the objective of resolving spectral structure below 10 nm. Again, generally good agreement among the various groups was obtained although some differences were noted. It is thus concluded that such systems can be constructed and can be useful in making routine measurements of activity-weighted size distributions with reasonable confidence in the results obtained

  2. Assessment of health impacts of radon exposures in Florida

    International Nuclear Information System (INIS)

    Vonstille, W.T.; Sacarello, H.L.A.

    1990-01-01

    This paper reports on residential radon levels, from a statewide Florida survey, that were used in an analysis of over 150,000 medically treated episodes of malignancies and other serious illnesses and conditions in whites, blacks and Hispanics from all counties in the state. No evidence of an increased percentage of cancer was found in any sex or ethnic group from the areas with the highest radon exposure levels. Age adjustment of data did not affect the results. The highest radon exposures were associated with some of the lowest cancer rates and contradict the risk assessment hypothesis based on extrapolation from exposures in mining. Points for DOE and EPA errors in risk assessment methods are reviewed; predictions from risk assessment should be empirically tested as in the case of any other scientific hypothesis before being used as a basis for public policy. Thus, the authors find that cancer risks of residential radon have been vastly overstated

  3. Radiation exposure in homes through radon and thoron daughter products

    International Nuclear Information System (INIS)

    Schmier, H.

    1984-01-01

    In a random selection of about 6000 homes in the Federal Republic of Germany, the radon concentration in room air has been measured using a simple dosemeter developed by Karlsruhe Nuclear Research Centre. The mean radon concentration has been determined to be approximately 40-50 Bqu/m 3 . If this experiment is taken as a representative survey for the FRG, the mean dose contributed by the natural radiation exposure through radon and its short-lived decay products to the effective annual dose to the lungs can be computed to be about 1 mSv (100 mrem), using the internationally accepted conversion factors. Apart from this survey, special radon measuring programmes have been carried out, including simultaneous recording of meteorological data, in order to obtain information on the parameters to be taken into account when describing the daily variations of radon concentrations. (orig./DG) [de

  4. Biological basis of inhalation exposure of radon and its daughters

    International Nuclear Information System (INIS)

    Matsuoka, Osamu

    1989-01-01

    Since inhalation exposure by radon and its daughters is very specific type of internal exposure, it is necessary to understand its characteristic nature. The specificity originates from the nuclear feature of radon daughters and the biological micro-environment in the respiratory tract. Inhaled radon and its daughters exist in the respiratory tract as ions attached to air dusts and deposit on the mucus surface of the respiratory tract by various mechanisms such as impaction, sedimentation and diffusion. Deposition of radon daughters is predominant around the site of the fourth generation according to Weibel's model. Deposited particles with radon daughters are cleared by muco-ciliary transportation. Its speed is estimated to be about 1.0 cm/min, at the upper region. Alpha decay will happen during transportation in the respiratory tract. Radon has no tissue affinity metabolically. Therefore, the irradiation is limited to the epithelial cells of respiratory tract. The cell components within 30-70 micron in depth are irradiated with alpha particle. Biological effectiveness of alpha radiation is very high compared with beta or gamma radiation. The target cell for carcinogenesis by radon exposure is considered to be the basal cell of epithelium. Lung cancer induced by radon inhalation is recognized to be squamous cell carcinoma, small cell carcinoma, or oat-cell carcinoma and adenocarcinoma. The modification factors which influence the effect of radon exposure are co-inhalation of ore dust and smoking habit. According to epidemiological studies on lung cancer which occurred in uranium miners, it is suggested that the smoking habit strongly promotes lung cancer induction. (author)

  5. Health effects and radiation dose from exposure to radon indoors

    International Nuclear Information System (INIS)

    Swedjemark, G.A.

    1998-01-01

    Radon exposure has been declared a health hazard by several organisations, for example the International Commission on Radiological Protection (ICRP) and the World Health Organisation (WHO). The basis for the risk estimate has been the results from epidemiological studies on miners exposed to radon, supported by the results of residential epidemiology. Only few of the many residential epidemiological studies carried out hitherto have a design applicable for a risk estimate. The largest is the Swedish national study but several large well designed studies are ongoing. An excess risk has also been found in animal research. The model describes smoking and radon exposure as between additive and multiplicative, found in both miners and residential studies. The relatively few non-smokers among the miners and also among the residents give a problem at estimating the radon risk for these groups. It would also be desirable to know more about the importance of the age and the time period at exposure. Lung dose calculations from radon exposure are not recommended by ICRP in their publication 66. For comparison with other radiation sources the ICRP recommends the concept 'dose conversion convention' obtained as the risk estimate divided by the detriment. Other effects of radon exposure than lung cancer have not been shown epidemiologically, but dose calculations indicate an excess risk of about 5% of the excess lung cancer risk. (author)

  6. Radon-daughter exposures in energy-efficient buildings

    International Nuclear Information System (INIS)

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

    1981-10-01

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

  7. Radon Research Program, FY 1991

    International Nuclear Information System (INIS)

    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

  8. A study on the risk from indoor radon 220 and radon 222 exposures

    International Nuclear Information System (INIS)

    Rannou, A.

    1986-12-01

    The hazards from radon (radon 220 and 222) in dwelling atmospheres have been studied. In the first part devoted to the present state of the problem, an analysis is made of the formation mechanisms and the evolution of radon and its daughters indoors. The main physical and dosimetric quantities required for the risk evaluation are defined. The theoretical and experimental analysis of the methods of measurements of radon and its daughters used in the measurement campaign are considered in the second part. The progress and the result of the national survey are developed in the third part. The effects of several factors on indoor levels are discussed. The conclusions of a particular study in the Finistere ''department'' are presented. The data collected make it possible to assess the mean exposure of man to natural radiation [fr

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

    International Nuclear Information System (INIS)

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

    2006-01-01

    The (CR-LR) difference technique, based on the CR-39 and LR 115 detectors, for the determination of implanted 210 Po 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 238 U and 232 Th 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 238 U and 232 Th concentrations in the relatively small real-life glass samples will make the retrospective radon exposure assessments impractical

  10. Variation of radon exposure in Damascus dwellings

    International Nuclear Information System (INIS)

    Shweikani, R.

    2012-01-01

    In the present work, activity concentrations of 222 Rn in air and 222 Rn and 226 Ra in drinking water were measured in Damascus city covering its old and modern parts. It was found that the average air radon activity concentration in the old part was higher than in the modern part, and in drinking water, radon was found to be 60±3 Bq/l, and less than 0.13 Bq/l for radium, which were lower than the recommended levels set by WHO. - Highlights: ► This work presents screening of natural radioactivity in dwellings in Damascus city. ► Radon, 226 Rn and total alpha/beta in air and drinking water were measured. ► Most of the obtained results were within the recommended levels set by WHO. ► In general radon in the old part was higher than the modern part of the city.

  11. Radon daughter exposure estimation and its relation to the exposure limit

    International Nuclear Information System (INIS)

    Stocker, H.

    1981-10-01

    Under current Atomic Energy Control Regulations, the annual limit for individual exposure to radon daughters is 4 WLM. The Regulations do not specify how the exposure is to be determined nor to what accuracy the measurements should be made. This paper discusses the historical and conventional grab-sampling and time-weighting methods for assigning exposures to radon daughters in uranium mines in Canada. As a further step in the evolution of exposure assignments, the system of personal radon daughter dosimetry is introduced as the more accurate means of assigning individual exposures and of adhering to the intent of the exposure limit

  12. Exposure of tour guides to Radon at the Cango caves

    International Nuclear Information System (INIS)

    Pule, O.J.; Lindsay, R.

    2008-01-01

    Full text: A study was commissioned by the National Nuclear Regulator of South Africa to investigate the radon levels in the Cango caves and the associated radiological exposure to tour guides. The Cango caves are about 1.3 km in length and are visited by about 300000 tourists per annum due to their natural beauty. This study followed an earlier investigation by the Department of Health which indicated levels in excess of 1000 Bqm -3 which could lead to excess exposure of the cave tour guides. Radon in the various cave chambers and radon exposure of tour guides was measured using RAD-7 continuous radon monitor, electrets ion chambers and personnel monitoring electrets respectively. The measurements in the cave were done during summer and winter seasons to determine any variations between the seasons. The occupancy time for individual guides and equilibrium factor were also investigated. The radon concentration in the cave range from 1000 Bqm -3 to more than 2000 Bqm -3 with equilibrium factor of approximately 0.4, and the variation between winter and summer measurements are insignificant. The radon exposure levels to tour guides differ due to various time periods they spent in the caves. The average dose to tour guides due to radon is 7 mSv -a and the highest exposure is about 10 mSv -a . The exposure to tourists is found to be insignificant due to time they spent in the cave. The regulatory authority is currently investigating what action is necessary to protect the tour guides. (author)

  13. Simulation of lifetime radon exposures using observation data

    International Nuclear Information System (INIS)

    Janssen, I.; Stebbings, J.H.

    1990-01-01

    The frequency distribution of lifetime risk of radon-induced lung cancer is a function of the frequency distribution of lifetime radon exposure, which differs from the frequency distribution of radon in homes because of residential mobility. Cumulative personal exposures are averages of a variable number of house radon values, weighted according to duration of occupancy and recency of residence. We simulated a distribution of individual, cumulative Working Level Month (WLM) exposures using observed residence histories from lung cancer cases from Eastern Pennsylvania and (basement) Working Levels (WL) from a survey of Reading Prong, Pennsylvania. The measurements for basement-level houses have a higher skewed distribution, well-approximated by a Gamma distribution with small shape parameter for this high-radon area, where 30% of the houses have basement radon levels that exceed 9 pCi/ell. Using the BEIR IV model and assuming a 50% occupancy factor, we assigned either lifetime residence in a single house or a real residence history at random for women randomly selected from the age distribution of female lung cancer cases. Averaging over houses reduces the exposure of the most highly exposed 5% of the population but increases it for 95%: the upper 25% attains lifetime exposure of ≥ 74 WLM, yielding a relative risk (RR) ≥ 2.1. Ignoring mobility and basing the calculations on the distribution of radon in houses, the corresponding values would be 48.0 WLM and a RR of 1.7. The 50th percentile of the population has an estimated WLM exposure of 34.6 (RR = 1.5); this estimate would be 16.8 (RR = 1.2) if we assume one house per lifetime

  14. A combined method for evaluating radon and progeny in waters and its use at Guarani aquifer, Sao Paulo State, Brazil

    International Nuclear Information System (INIS)

    Bonotto, D.M.; Mello, C.B.

    2006-01-01

    A combined method for evaluating radon ( 222 Rn) and progeny ( 214 Pb and 214 Bi) in water was developed by using inexpensive alpha scintillation counting and gamma ray spectrometry through NaI(Tl) scintillation detectors. A groundwater sample collected at the Pocos de Caldas alkaline massif in Brazil was submitted to the technique in order to assure its applicability by comparing the volumetric activities by different methods. Similar volumetric activity was determined for 214 Pb and 214 Bi in the sample analyzed that is compatible with the expected condition of radioactive equilibrium between these nuclides. The combined method was successfully used to analyze groundwater samples from Guarani aquifer in Sao Paulo State, Brazil, and the results of the measurements indicated that 214 Pb and 214 Bi provide useful information concerning the evaluation of the drinking water quality in terms of radiological aspects. This is because they are directly identified in the water samples, without the need of requiring the assumption of the establishment of the transient equilibrium condition with its parent 222 Rn

  15. A combined method for evaluating radon and progeny in waters and its use at Guarani aquifer, Sao Paulo State, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Bonotto, D.M. [Departamento de Petrologia e Metalogenia, Universidade Estadual Paulista (UNESP), IGCE-Instituto de Geociencias e Ciencias Exatas, Av. 24-A, No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil)]. E-mail: dbonotto@rc.unesp.br; Mello, C.B. [Departamento de Petrologia e Metalogenia, Universidade Estadual Paulista (UNESP), IGCE-Instituto de Geociencias e Ciencias Exatas, Av. 24-A, No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil)

    2006-07-01

    A combined method for evaluating radon ({sup 222}Rn) and progeny ({sup 214}Pb and {sup 214}Bi) in water was developed by using inexpensive alpha scintillation counting and gamma ray spectrometry through NaI(Tl) scintillation detectors. A groundwater sample collected at the Pocos de Caldas alkaline massif in Brazil was submitted to the technique in order to assure its applicability by comparing the volumetric activities by different methods. Similar volumetric activity was determined for {sup 214}Pb and {sup 214}Bi in the sample analyzed that is compatible with the expected condition of radioactive equilibrium between these nuclides. The combined method was successfully used to analyze groundwater samples from Guarani aquifer in Sao Paulo State, Brazil, and the results of the measurements indicated that {sup 214}Pb and {sup 214}Bi provide useful information concerning the evaluation of the drinking water quality in terms of radiological aspects. This is because they are directly identified in the water samples, without the need of requiring the assumption of the establishment of the transient equilibrium condition with its parent {sup 222}Rn.

  16. Comparative study of radon exposure in Canadian homes and uranium mines - a discussion on the importance of national radon program

    International Nuclear Information System (INIS)

    Chen, Jing

    2017-01-01

    The history of lung cancer in uranium miners is well known for over hundreds of years when the disease was referred to as 'miner's disease' or 'mountain sickness'. Radon levels in uranium mines have decreased significantly over the past 30 years as a result of effective radiation protection measures at workplaces. For the most recent 10-year period, the average radon concentrations to underground and surface workers in Canadian uranium mines were 111 and 11 Bq m -3 , respectively. Based on the recent radon survey carried out in roughly 14 000 homes in 121 health regions across Canada and the more recent radon and thoron survey in 33 Canadian cities and 4000 homes, the average radon concentration in Canadian homes is 77 Bq m -3 . This study demonstrates that, nowadays, workers are exposed to radon in underground mines at a comparable radon level to what Canadians are exposed to at home. Since exposure to indoor radon is the main source of natural radiation exposure to the population, it is important for the National Radon Program to further increase radon awareness, and to encourage more Canadians to take appropriate actions to reduce radon exposure. (authors)

  17. The radon in Corsica: evaluation of exposure and associated risks

    International Nuclear Information System (INIS)

    2006-02-01

    The average level found in Corsica is superior to that one found in France. On the basis of the results of it campaign I.R.S.N.-D.G.S., the French average is of 90 Bq.m 3 against 197 Bq.m 3 for Corsica. The risk of dying from a lung cancer attributable to the radon was estimated at 13 % in France. The evaluation of risk led on Corsica shows a risk attributable to the radon included between 21.5 and 28 %.This evaluation of risk is only a stage. It is important to arrest better the exposure to the radon of the Corsican population. For a good estimation of the levels of radon and thus the impact of this one, additional measures are necessary. The results of the data analysis of exposure allow to guide the choice of the new measures: a campaign on the season effect in Corsica and a completion of the measures in housing are two main axes.Seen the importance of the interaction between the tobacco and the radon, a good estimation of the tobacco customs in Corsica and its evolution in the time seems essential to estimate indeed the impact of the radon in this region. (N.C.)

  18. Radon gas exposure levels in some selected areas in Egypt

    International Nuclear Information System (INIS)

    Ali, E.M.; Taha, T.M.; Gomaa, M.A.; El-Hussein, A.M.; Ahmed, A.A.

    2005-01-01

    During a summer season of 2003, the atmospheric concentrations of radon gas were measured indoor every one-hour for twenty-four hour measurements in some selected areas, using Pylon-AB4. Two hundreds and forty samples were monitored to determine the concentration of radon gas at each location using high-efficiency Lucas type continuous passive cell. The average values of radon gas concentration were taken in three time intervals 6.00:18.00, 18.00:6.00 and whole day. The average values of indoor radon gas of two locations using three time intervals were 4.82±0.63, 9±0.71 and 6.9±0.33 and 9.6±0.23, 11.82±0.42 and 9.37±0.7 Bq/m /h. respectively. The exposure levels were within the ICRP and EPA recommendations

  19. Monitoring of the radon exposure in workplaces: Regulatory approaches

    International Nuclear Information System (INIS)

    Ettenhuber, E.

    2002-01-01

    Germany has a reference level of 2 10 6 Bqh/m 3 for radon in workplaces, corresponding to an annual dose of 6 mSv and a limit of 6 10 6 Bqh/m 3 , corresponding to 10 mSv/y. If the reference level is exceeded remedial action has to be taken and a new radon measurement should be carried out. If it is not possible to reduce the radon concentration below the reference level the competent authority has to be notified and monitoring of the radon concentrations performed. Germany has performed a study to investigate the exposure by natural radionuclides in workplaces in a large number of industrial activities, with a dose assessment of the workers under normal circumstances. They made a categorization of NORM activities in dose ranges of 20 mSv/y. Most of the NORM activities fall in the category <1 mSv/y when normal occupational hygiene measures are taken

  20. Exposure to radon in Cuban tourist caves

    International Nuclear Information System (INIS)

    Carrazana Gonzalez, Jorge; Dominguez Ley, Orlando; Gil Castillo, Reinaldo; Molerio Leon, Leslie

    2008-01-01

    With the objective of estimating the dose, due to Radon-222, received by tour guides and other people who work inside some of the most important tourist caves in the Republic of Cuba, measurements of radon concentrations were carried out in four of these caves: Santo Tomas Cave, Tapiada Cave, Del Indio Cave and Jose Miguel Cave. All these caves are located in the Vinales Valley (Pinar del Rio City), a very important tourist area in the country. The relationship among radon concentration, the concentration of natural radionuclides inside the caves and the geologic characteristics of the specific locations was analyzed. In order to select the most appropriates measurement places, different criteria were taken into account: representatives points of the geology of the caves, level of gamma radiation, exchange of air, places of work inside the caves (cafeterias, restaurants and shops) and places more frequently visited by tour guides. The maximum radon concentration was found in Jose Miguel Cave with a value of 220 Bq/m 3 . The measurement of gamma dose rate inside the caves was carried out with a scintillation detector type Scintrex BGS-3 previously calibrated at SSI, Sweden. The radon concentrations were measured with the equipment Alpha Guard PQ2000/MC50 and SARAD RM2000, both also calibrated at SSI, Sweden. The obtained results indicated that, in the studied caves, the annual dose is not greater than 1 mSv considering a work year of 2000 hours. (author)

  1. Bill proposition related to the protection of persons against exposure to radon in dwellings - Nr 4390

    International Nuclear Information System (INIS)

    Dord, Dominique; Colombier, Georges; Forissier, Nicolas; Luca, Lionnel; Carayon, Bernard; Blanc, Etienne; Remiller, Jacques; Perrut, Bernard; Voisin, Michel; Diard, Eric; Poletti, Berengere; Fort, Marie-Louise; Ciotti, Eric; Guibal, Jean-Claude; Gest, Alain; Roccaserra, Camille de; Delatte, Remi

    2012-01-01

    After having recalled the extent of the risk associated with exposure to radon in France, and that a regulation already exists for professional premises and buildings receiving public, this document contains the measures proposed to define a regulatory framework for dwellings. It addresses radon concentration values, radon volume activity thresholds, radon diagnosis practices, actors, protocols and reports

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

    Energy Technology Data Exchange (ETDEWEB)

    Whicker, Jeffrey J [Los Alamos National Laboratory; Mcnaughton, Michael [Los Alamos National Laboratory

    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.

  3. Protective measures during construction against radon exposure

    International Nuclear Information System (INIS)

    Horn, W.

    1990-01-01

    Radon, thoron as well as their daughter products have an cancerogeneous effect on the human respiratory tracts. In this respect protective measures in the area of construction are of great importance. This article deals with constructional solutions which consist of different individual measures. Sources of radon are outside air, water, fuels, building materials as well as the building ground. Possible protective measures are divided into area-related (floor structure, intermediate floors, exterior walls of cellar, foundation slab, building ground), line-related (joints, cracks, wall ducts) as well as supplementary measures (tightly closing doors, arrangement of natural cross-ventilation and vertical ventilating shafts). (BWI) [de

  4. Lung pathology and exposure to radon daughters

    International Nuclear Information System (INIS)

    Saccomanno, G.

    1980-01-01

    The data presented suggest that the primary carcinogen of lung cancer in uranium miners is cigarette smoking because the incidence of lung cancer in noncigarette smokers is insignificant. In cigarette-smoking uranium miners, however, the incidence of cancer in those exposed to significant amounts of radon daughters is higher than in the smoking, nonmining population. This suggests that radon is an additive carcinogen if the lung has been injured by the cigarette-smoking carcinogen. Preliminary studies measuring DNA, T cells, and rosette inhibition immunological studies indicate closer monitoring of uranium miners' health during this occupation may be justified

  5. Health effects of radon

    International Nuclear Information System (INIS)

    Easterly, C.

    1994-01-01

    Exposure of people to radon has taken on increased interest during the last decade because of the understanding that buildings can serve to trap radon and its daughters, and thereby build up undesirable concentrations of these radioactive elements. Numerous studies of underground miners (often uranium miners) have shown an increased risk of lung cancer in comparison with nonexposed populations. Laboratory animals exposed to radon daughters also develop lung cancer. The abundant epidemiological and experimental data have established the carcinogenicity of radon progeny. Those observations are of considerable importance, because uranium, from which radon and its progeny arise, is ubiquitous in the earth's crust, including coal mines. Risk estimates of the health effects of long-term exposures at relatively low levels require continued development, especially to address the potential health effects of radon and radon daughters in homes and occupational settings where the exposure levels are less than levels in underground uranium and other metal mines that have been the subject of epidemiological studies. Two approaches can be used to characterize the lung-cancer risks associated with radon-daughter exposure: mathematical representations of the respiratory tract that model radiation doses to target cells and epidemiological investigation of exposed populations, mainly underground uranium miners. The mathematically-based dosimetric approach provides an estimate of lung cancer risk related to radon-daughter exposure based specifically on modeling of the dose to target cells. The various dosimetric models all require assumptions, some of which are not subject to direct verification, as to breathing rates; the deposition of radon daughters in the respiratory tract; and the type, nature, and location of the target cells for cancer induction. The most recent large committee effort drawn together to evaluate this issue was sponsored by the National Research Council

  6. Health Risks due to Exposure to Radon in Homes in Ireland

    International Nuclear Information System (INIS)

    2005-09-01

    This document summarises the evidence that links exposure to radon in homes with an increase in lung cancer. Using the most recent risk estimates derived from epidemiological studies carried out abroad, the risk associated with radon exposure in homes in Ireland is derived. The relationship between exposure to radon and cigarette smoking is also discussed

  7. Radon and radon-daughter exposure measurements by through-etched track registration in cellulose nitrate

    International Nuclear Information System (INIS)

    Knoefell, T.M.J.; Silva Estrada, J.J. da; Tavares, O.A.P.; Martins, J.B.

    1981-01-01

    The use of cellulose nitrate films LR-115 type II (Kodak-Pathe) as a practical, exposure integrating device to measure the level of exposure to alpha particles in atmospheres which contain radon and radon-daughter products is investigated. The analysis of a number of cellulose nitrate films that have been exposed to calibrated radon test-chamber atmospheres has indicated good correlations between through-etched track density p and integrated alpha-particle exposure Σa (Working-Level-Hour). It is shown that the response of the cellulose nitrate detector to radon-daughter alpha-particle exposures is linear, and that reliable conservative estimations of the Working-Level-Hour can be obtained from Σa = 3.0(p-b), where p is expressed in tracks/mm 2 (b is the background level). These results recommend the use of the special red cellulose nitrate films as a convenient dosimeter for monitoring radioactive contaminants in mine atmospheres. (Author) [pt

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

    Science.gov (United States)

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

    2016-03-30

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

  9. Dose conversion of radon exposure according to new epidemiological findings

    International Nuclear Information System (INIS)

    Tomasek, L.; Rogel, A.; Laurier, D.; Tirmarche, M.

    2008-01-01

    In 1993, ICRP-65 recommended that dose conversion of radon exposure should be based on the comparison of detriments between radon exposure and effective dose. The lifetime detriment from the radon exposure was projected according to the epidemiological studies of uranium miners then available. The projection model (GSF) was multiplicative with temporal and age-at-exposure modification. Since 1993, new studies of uranium miners have appeared and many original studies were updated. In addition, projections of the risk have been improved by including further modifying factors as for instance in BEIR VI. New analyses were completed in the Czech and French studies of uranium miners with accurate estimates of exposures based on extensive radon measurements. The resulting estimates of excess absolute lifetime risk per unit exposure in working level months (WLM) from these models lead to dose conversion of 10 mSv WLM -1 for the BEIR VI model and 8 mSv WLM -1 for the joint Czech-French model in contrast to the conversion of 5 mSv WLM -1 for the GSF model. (authors)

  10. Preventing excessive radon exposure in U.K. housing

    International Nuclear Information System (INIS)

    Miles, J.C.H.; Cliff, K.D.; Green, B.M.R.; Dixon, D.W.

    1992-01-01

    In the United Kingdom (UK) it has been recognized for some years that some members of the population received excessive radiation exposure in their homes from radon and its decay products. To prevent such exposures, an Action Level of 400 Bq m -3 was adopted in 1987. In January, 1990, the National Radiological Protection Board (NRPB) advised that the Action Level should be reduced to 200 Bq m -3 , and this advice was accepted by the Government. It is estimated that exposures in up to 100,000 UK homes exceed this Action Level; this amounts to about 0.5% of the available housing. The UK authorities have developed a strategy for preventing such exposures: (1) Areas in which it is estimated that >1% of homes exceed the Action Level for radon are being designated as Affected Areas, and a program to map such areas is under way. Households in these areas are advised to have radon measurements made by NRPB under a open-quotes freeclose quotes (Government-funded) scheme. (2) Householders found to have whole-house, whole-year average radon concentrations >200 Bq m -3 are advised to take remedial action and are provided with information on how this can be done. Partial grants toward remedial work are available in cases of financial need. So far, around 3000 such households have been identified. (3) Within Affected Areas, localities are being defined where new homes must incorporate precautions against radon exposure. In addition to this strategy, a joint case-control study of the risks of radon in homes is being undertaken by the Imperial Cancer Research Fund and NRPB, supported by the UK Government and the Commission of the European Communities

  11. Occupational exposure to radon daughters in buildings

    International Nuclear Information System (INIS)

    Dixon, D.W.

    1985-01-01

    Results are presented for radon daughter concentrations in 70 premises of either factory-type or office-type in Cornwall. It is concluded that attention may need to be directed to offices in parts of the UK, the principal reason being their generally low ventilation rates. (U.K.)

  12. Cost effectiveness of reducing radon exposure in Spanish dwellings

    International Nuclear Information System (INIS)

    Colgan, P.A.; Gutierrez, J.

    1996-01-01

    Published information on the distribution of radon levels in Spanish single family dwellings is used to evaluate the cost-effectiveness of three different intervention scenarios: remediation of existing dwellings, radon proofing of all future dwellings and the targetting of areas with higher than average indoor radon concentrations. Analysis is carried out on the basis of a Reference Level of 400 Bq m -3 for the existing housing stock and 200 Bq m -3 for new dwellings. Certain assumptions are made about the effectiveness and durability of the measures applied and annualised costs are used to calculate the costs per lung cancer death averted. The results reveal that targetting future housing is a more cost-effective option than remediation of existing dwellings with radon concentrations above the Reference Level -the costs per lung cancer death averted are typically $145000. In high-risk areas, these costs can be considerably less, depending on the percentage of dwellings expected to exceed the Reference Level and the average savings in exposure as a result of the intervention. The costs of intervention to reduce lung cancer deaths following exposure to radon compare favourably with those of other health programmes in other countries. (Author)

  13. Radon

    Science.gov (United States)

    ... radon-resistant features. These features include gravel and plastic sheeting below the foundation, along with proper sealing ... lower the radon level. Detailed information about radon reduction in your home or building can be found ...

  14. The effect of RTP (Radon Thoron Progeny) and dust loading on the design of an alarm system for airborne plutonium particulates

    International Nuclear Information System (INIS)

    Pai, H.L.; Sun, L.C.

    2004-01-01

    If the alpha method is adopted, the main problem for determining airborne plutonium particulates is the overlapping of the alpha spectrum between Pu and RTF (radon thoron progeny). The order of magnitude estimation establishes that RTP is more than 20 times higher than Pu. Therefore a method of discriminating RTP is required. The primary methods of discrimination are the aerosol size and the alpha spectrum methods. If the alpha spectrum method is adopted, the formation of the low energy tail of RTP should be investigated. Preliminary study indicates that the low energy tail is related to the air gap and dust loading. (author)

  15. Analysis of errors in the measurement of unattached fractions of radon and thoron progeny in a Canadian uranium mine using wire screen methods

    International Nuclear Information System (INIS)

    Khan, A.; Phillips, C.R.

    1987-01-01

    The unattached fraction of radon/thoron progeny in uranium mines is generally small and therefore difficult to measure accurately. The simple wire screen method provides a direct estimate of the unattached fraction from the screen count, or an indirect estimate from the difference between the reference and back-up filter counts. Wire screen method results are often difficult to analyse, especially when the unattached activity is small. Experimental data obtained in Canadian uranium mines are presented here, together with a detailed error analysis. The method consisting of counting the wire screen and the back-up filter is found to be the most precise method for unattached fraction determination. (author)

  16. Risks from exposure to radon at home or at work

    International Nuclear Information System (INIS)

    Chambers, D.B.; Stager, R.H.

    2010-01-01

    This paper examines the risks associated with exposure to radon decay products through estimation of lifetime excess absolute risks (LEAR) per WLM for selected epidemiological risk projection models from miner studies and pooled residential radon studies applied to the ICRP 103 [6] reference populations. The mSv per WLM was calculated using the total detriment per Sv factor. The effect of smoking was considered based on application to Canadian mortality data by smoking status. There was a large variation in the risk per WLM and dose conversion factor depending on the smoking histories which vary substantially between individuals and over time. (author)

  17. Exposure to radon in Sweden dwellings - attitudes and elimination

    International Nuclear Information System (INIS)

    Jansson, B.; Tholander, M.; Axelson, O.

    1989-01-01

    Owners of 208 dwellings with radon daughter concentrations of 400 Bq/m 3 EER or above were asked about attitudes and measures toward elimination via mailed questionnaires. The response rate was 88% and some steps toward elimination had been taken in 83 dwellings. For the remaining houses, no improvements had been made either because of financial problems, lack of technical advice, or doubts about radon daughter exposure as a health hazard. The results of this study suggest the need to more definitely assess the risk through epidemiologic studies, as well as to provide more information about technical solutions and financial support to house owners

  18. Exposure to radon in caves and abandoned mines

    International Nuclear Information System (INIS)

    Dixon, D.W.

    1996-01-01

    The significance for health of exposure to radon daughters during leisure excursions in discussed mines or caves is considered for visitors with interests in speleology, mineral collecting, mining history and youth training. General members of the public might also enter tunnels. Potential annual exposures based on radon measurements in various mines and caves are estimated and it is concluded that the annual exposure of individuals who undertake frequent and prolonged trips to underground systems might exceed 10 6 Bq h m -3 . Exposures to general members of the public are likely to be much lower. The National Radiological Protection Board has developed proposals for a coherent and comprehensive scheme to promote dose limitation in a wide range of circumstances. These are described, with current initiatives on consultation with National Associations, local Government and many special interest groups. (author)

  19. Radon exposure and tumors of the central nervous system.

    Science.gov (United States)

    Ruano-Ravina, Alberto; Dacosta-Urbieta, Ana; Barros-Dios, Juan Miguel; Kelsey, Karl T

    2017-03-15

    To review the published evidence of links between radon exposure and central nervous system tumors through a systematic review of the scientific literature. We performed a thorough bibliographic search in Medline (PubMed) and EMBASE. We combined MeSH (Medical Subject Heading) terms and free text. We developed a purpose-designed scale to assess the quality of the included manuscripts. We have included 18 studies, 8 performed on miners, 3 on the general population and 7 on children, and the results have been structured using this classification. The results are inconclusive. An association between radon exposure and central nervous system tumors has been observed in some studies on miners, but not in others. The results observed in the general adult population and in children are also mixed, with some research evincing a statistically significant association and others showing no effect. We cannot conclude that there is a relationship between radon exposure and central nervous system tumors. The available studies are extremely heterogeneous in terms of design and populations studied. Further research is needed in this topic, particularly in the general population residing in areas with high levels of radon. Copyright © 2017 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. Radon exposure of passengers in the Prague metro

    International Nuclear Information System (INIS)

    Sabol, J.

    1996-01-01

    This paper summarises the results of radon concentration monitoring in the carriages and at some stations of the Prague Metro network. The measurements revealed that radon levels in the Metro are relatively low in comparison to those normally encountered in dwellings in the Prague region. On average, the radon concentrations in the air inside the carriages have been found to be about 11 - 12 Bq m -3 while the levels at most stations reached values between 10 and 15 Bq m -3 . The Metro is intensively ventilated by means of powerful blowers and fans; the piston effect of the moving trains also contributes to air exchange. The ventilation rate is typically 3-4 h -1 . The highest rate is in line C, where the air in all underground areas is completely exchanged 6 times within each hour. These results demonstrate that Metro passengers receive about the same effective dose as passengers using surface transport. The doses from radon in the metro are only slightly higher than radon-related doses in the open air, while exposure due to external photon radiation seems to be a few percent lower than dose rates common in typical Czech houses. (author)

  1. Standardization of radon measurements

    International Nuclear Information System (INIS)

    Matuszek, J.M.; Hutchinson, J.A.; Lance, B.H.; Virgil, M.G.; Mahoney, R.J.

    1988-01-01

    Radon escaping from soil into homes appears to present the single greatest source of radiation exposure that most people will ever face. Measurement protocols for the relatively inert gas inextricably link the method of collection with the counting of the specimen. The most commonly used methods depend on the measurement of dislocation sites on plastic α-track detectors or on the adsorption of radon onto activated charcoal for subsequent counting of the γ-rays produced by decay of the radon progeny. The uncertainties inherent to the radon-measurement methods used commercially in the United States are far greater than those for measurements of other environmental radionuclides. The results of this preliminary study raise doubts as to whether existing proficiency-testing programs can provide assurance that radon-measurement methods are representative of actual conditions in any dwelling. 17 refs., 1 figs., 4 tabs

  2. Indoor radon exposure in Norway and lung cancer risk

    International Nuclear Information System (INIS)

    Sanner, T.; Dybing, E.

    1990-01-01

    The risk for lung cancer due to indoor radon in Norway was estimated. The risk factor recommended by the World Health Organization was used. Corrections were made for time not spent at home and type of activity. On the basis of measurements by the Norwegian National Institute for Radiation Hygiene in 7,500 homes, Strand et al estimated that the average concentration of radon daughters in the bedroom of Norwegian dwellings was 26.5 Bq/m 3 (EER). The level of exposure during time spent outside the home was assumed to be 10% of that at home. It was calculated that indoor radon exposure may cause 75-225 lung cancer deaths per year. This corresponds to about 5-15% of all lung cancer deaths in Norway. The risk for lung cancer death per 1,000 deaths at an indoor radon decay product level of 100 Bq/m 3 was calculated on the basis of various reports in the paper. The results show that the present risk estimate is lower than most of the other estimates

  3. Radon exposure in selected underground touring routes in Poland

    International Nuclear Information System (INIS)

    Olszewski, J.; Chruscielewski, W.; Jankowski, J.

    2006-01-01

    The radioactive elements abounding in the natural environment cause that the whole human population is exposed to radiation. In Poland, mean gamma radiation dose power is 45.4 n Gy h -1 , while atmospheric radon concentration is 4.4 Bq m -3 [1]. In closed rooms, where radon tends to accumulate, the concentrations may be many times higher.Underground touring routes located in caves, mines, ancient cellars, vaults may accumulate radon at concentrations several thousand times exceeding its atmospheric levels. Studies on natural radioactivity in underground touring routes, with particular reference to caves, have continued worldwide since the 80's. Current register of underground touring routes in Poland comprises over 30 items, which include caves (e.g. Niedzwiedzia), mines (Wieliczka), cellars and underground stores (Opatow City vaults) and military objects (underground factories of Walim). The Nofer Institute of Occupational Medicine has for several years already continued determinations of periodical mean radon concentrations in four underground touring routes (starting date in parentheses): Niedzwiedzia Cave (1995); Kowary Drifts closed uranium mine (2001); closed uranium mine in Kletno (2004); Zloty Stok closed gold mine (2004); Osowka underground city in Gluszyca (2004).The results of our determinations of radon concentrations at five selected touring routes lead to the following conclusions. 1. The exposure in the Kowary Drifts touring route is at the level of 5% of the recommended maximum annual admissible limit of 20 mSv. 2. It is assessed that workers of the touring routes where exposures are estimated from the measured concentrations and the time spent underground may receive doses ranging from 0.01 to 5 mSv. (N.C.)

  4. Radon exposure in selected underground touring routes in Poland

    Energy Technology Data Exchange (ETDEWEB)

    Olszewski, J.; Chruscielewski, W.; Jankowski, J. [Nofer Institute of Occupational Medicine, Dept. of Radiation Protection, Lodz (Poland)

    2006-07-01

    The radioactive elements abounding in the natural environment cause that the whole human population is exposed to radiation. In Poland, mean gamma radiation dose power is 45.4 n Gy h{sup -1}, while atmospheric radon concentration is 4.4 Bq m{sup -3} [1]. In closed rooms, where radon tends to accumulate, the concentrations may be many times higher.Underground touring routes located in caves, mines, ancient cellars, vaults may accumulate radon at concentrations several thousand times exceeding its atmospheric levels. Studies on natural radioactivity in underground touring routes, with particular reference to caves, have continued worldwide since the 80's. Current register of underground touring routes in Poland comprises over 30 items, which include caves (e.g. Niedzwiedzia), mines (Wieliczka), cellars and underground stores (Opatow City vaults) and military objects (underground factories of Walim). The Nofer Institute of Occupational Medicine has for several years already continued determinations of periodical mean radon concentrations in four underground touring routes (starting date in parentheses): Niedzwiedzia Cave (1995); Kowary Drifts closed uranium mine (2001); closed uranium mine in Kletno (2004); Zloty Stok closed gold mine (2004); Osowka underground city in Gluszyca (2004).The results of our determinations of radon concentrations at five selected touring routes lead to the following conclusions. 1. The exposure in the Kowary Drifts touring route is at the level of 5% of the recommended maximum annual admissible limit of 20 mSv. 2. It is assessed that workers of the touring routes where exposures are estimated from the measured concentrations and the time spent underground may receive doses ranging from 0.01 to 5 mSv. (N.C.)

  5. Monitoring employee exposure to radon and its daughters in uranium mines

    International Nuclear Information System (INIS)

    Leach, V.A.; Lokan, K.H.

    1979-06-01

    Practical methods for measuring the concentration in air of radon and radon daughter are reviewed, and straightforward procedures are described for reliable field measurements. Typical field data, and sample calculations are provided, together with suitable procedures for calculating and reporting cumulative radon daughter exposures

  6. Radon exposure at specific workplaces in Austria experiences and future challenges

    International Nuclear Information System (INIS)

    Gruber, V.; Ringer, W.

    2017-01-01

    Radon exposure at specific workplaces like water works, radon spas, tourist mines and show caves were evaluated in Austria within pilot studies (2004-10) and have been regulated in an ordinance since 2008. In this article, the major results and experiences in radon measurements and dose assessments at those workplaces by the accredited AGES laboratory are presented. (authors)

  7. Residential Radon Exposure and Lung Cancer: Evidence of an Inverse Association in Washington State.

    Science.gov (United States)

    Neuberger, John S.; And Others

    1992-01-01

    Presents results of a descriptive study of lung cancer death rates compared to county levels of radon in Washington State. Age-specific death rates were computed for white female smokers according to radon exposure. A significant lung cancer excess was found in lowest radon counties. No significant difference was found between the proportion of…

  8. Occupational radon daughter exposure in underground workplaces in Norway

    International Nuclear Information System (INIS)

    Strand, T.; Kolstad, A.K.

    1991-01-01

    Occupational doses from radon daughter exposure in different underground environments in Norway have been estimated. Monitoring programs have been undertaken in mines, hydroelectric power stations, defence installations and tunnels. Based on these measurements the average effective dose equivalent and the corresponding collective effective dose equivalent have been estimated. Hydroelectric power stations is the largest group. In 1984 and 1985 measurements were performed in about 130 of the appr. 150 facilities in Norway. The average radon concentration was about 270 Bq/m 3 , and the corresponding average annual effective dose equivalent between 2 and 2.5 mSv. In 1984 there were about 19 mines in operations in Norway. Based on the measurements, the average radon concentration in mines is 260 Bq/m 3 , and the corresponding average annual effective dose equivalent 3.4 mSv. However, at the time being there are only 10 mines in operation and the number of miners has been reduced from about 1400 in 1984 to about 900 in 1990. The measurements show that the average level of radon in defence installations and tunnels is less than in mines and hydroelectric power stations. The total collective effective dose equivalent for workers underground in Norway is estimated in this paper to be between 5 and 7 manSv. 9 refs., 3 tabs

  9. Direct progeny detection techniques and random epidemiology

    International Nuclear Information System (INIS)

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

    2015-01-01

    Over the past 40 years, there has been considerable progress in the measurements methods and their application to the estimates of risks due to radon among general populations. The previous decade saw major development in this regard. It was the direct estimate of indoor radon risk from epidemiological studies in Europe and North America. These were important findings that demonstrated the presence of lung cancer risks at residential radon levels supplementing the generally used risks estimates at high exposures obtained from uranium miner's data. The residential radon epidemiological studies largely used radon concentration as a measure of exposure. The exposure to decay products, which are primarily the dose givers, are assumed to be proportional to the measured gas concentrations. Also, the presence of thoron was neglected in these studies. Although several corrections have appeared to these assessments, the question of variability of actual decay product exposures has largely remained unaddressed. In order to circumvent this limitation, passive techniques were developed to estimate the decay product concentrations directly using deposition monitors. These are based on detecting the alpha particles from decay products deposited on an absorber mounted LR-115 detectors. Known as Direct radon, and Thoron Progeny sensors (DRPS/DTPS), these have been further refined to separate fine fraction from the coarse fraction by wire-mesh capping techniques. Large number environmental calibration exercises and field data generation has been carried out on the progeny concentrations in Indian and some European environments. The development of progeny sensors offers a new tool for future epidemiology. Since in the Indian context, there exist no radon related epidemiological estimates of risk, it is time one conducts large scale studies to seek possible correlations between DRPS/DTPS data and lung cancer risks. While epidemiological studies in High background radiation areas

  10. Terminology for describing radon concentrations and exposures

    International Nuclear Information System (INIS)

    Robkin, M.A.

    1987-01-01

    Starting with a collection of identical radioactive atoms, the time it takes for one-half of them to decay is called the half-life. The decay product, or daughter atoms, may also be radioactive, in which case it will decay into another radioactive daughter. This process will continue until finally a stable, i.e. non-radioactive, daughter is reached. Each radioactive daughter has its own characteristic half-life and radiations. The decay rate has traditionally been specified in curies (Ci). The original curie unit was based on the decay rate of one gram of radium-227, which is approximately 37 billion disintegrations per second (dps). The curie is now defined to be exactly this rate. It is often convenient, particularly in discussing radon, to introduce a smaller unit, the picocurei (p,Ci), where 1 pCi = 10/sup -12/ Ci. In international usage, a new unit, the Becquerel (Bq), has recently been adopted. This unit is part of the system International de Unites (S.I.) and is equal to one disintegration per second (dps) or about 27 pCi

  11. Radon

    International Nuclear Information System (INIS)

    1990-01-01

    This leaflet in the At-a-Glance Series, describes what radon is, where it is found, why it presents a risk to health, the official advice, and the remedies that are available to reduce radon levels. (author)

  12. Quantification of the lung cancer risk from radon daughter exposure in dwellings - an epidemiological approach

    International Nuclear Information System (INIS)

    Edling, C.; Wingren, G.; Axelson, O.

    1986-01-01

    Some epidemiological studies have suggested a relationship between the concentration of decay products from radon, i.e., radon daughter exposure, in dwellings and lung cancer. Further experiences made from radon measurements have indicated that both building material and particularly the radioactivity in the ground is of importance for the leakage of radon into the houses. In Sweden, a survey is now ongoing in 15 municipalities with alum shale deposits, and in one area a case-referent evaluation has been made, considering building materials, ground conditions and smoking habits. The size of the study is small, but the results suggest that a risk is at hand and that there is a multiplicative effect from smoking and radon daughter exposure. About 30% of the lung cancers in the studied population might be attributable to elevated and potentially avoidable exposure to radon and radon daughters. (author)

  13. Strategy to reduce radon exposure in Norway; Strategi for aa redusere radoneksponeringen i Norge

    Energy Technology Data Exchange (ETDEWEB)

    2009-06-15

    Radon in indoor air is a more widespread problem in Norway than in many other countries. It can be estimated that radon in indoor air causes about. 300 lung cancer deaths annually in Norway. Norway, together with Sweden and Finland, are among the countries in the world with the highest average concentration of radon in indoor air. Geological conditions and the cool climate provides great challenges, but radon problem can be solved in a cost effective way. The risk increases with exposure and is proportional with radon concentrations in indoor air and exposure time. The risk from radon, however, no lower threshold value. Moreover, the risk is highest for those who smoke and those who have smoked previously, but non-smokers can also develop lung cancer as a result of radon exposure. In recent years it has been conducted three large, important international joint studies that confirm earlier estimates of the risk. (AG)

  14. Evaluation of the risk of exposure to radon

    International Nuclear Information System (INIS)

    Monchaux, G.

    2001-01-01

    The aim of this project was to assess the risk due to inhalation of radon and its decay products using a horizontal approach across a large-scale research programme. The central objective was the assessment of human risk, a task that required a combination of several programmes and involved a multidisciplinary approach. Five main topics were addressed: radioactive aerosol studies, modelling, human studies, animal studies and retrospective assessment of radon exposure. The five studies were distributed between working groups. The rationale of this project was to pool the expertise from laboratories working in different fields of radiation protection. This paper summarises the main achievements made through this multidisciplinary research programme and the synergies that occurred between the different groups. (author)

  15. Radon in an underground cave system in Victoria

    International Nuclear Information System (INIS)

    Hedt, J.C.; Boal, T.J.

    1998-01-01

    Radon levels in a cave system in Victoria have been measured. The variation of radon and radon progeny levels with time, position throughout the cave and season have been determined. The radiation exposure of tour guides were estimated. The data is being used to develop a radiation management plan for the tour guides. Radon concentration within a cave system was proven to be dependent to a large extent upon the rate of air exchange with outside. Cave ventilation is the single most important factor in determining if there is diurnal variation in the radon concentration

  16. Canadian individual risks of radon-induced lung cancer for different exposure profiles.

    Science.gov (United States)

    Chen, Jing

    2005-01-01

    Indoor radon has been determined to be the second leading cause of lung cancer after tobacco smoking. There is an increasing need among radiation practitioners to have numerical values of lung cancer risks for men and women, ever-smokers and never-smokers exposed to radon in homes. This study evaluates individual risks for the Canadian population exposed to radon in homes at different radon concentrations and for different periods of their lives. Based on the risk model developed recently by U.S. Environmental Protection Agency (EPA), individual risks of radon-induced lung cancers are calculated with Canadian age-specific rates for overall and lung cancer mortalities (1996-2000) as well as the Canadian smoking prevalence data in 2002. Convenient tables of lifetime relative risks are constructed for lifetime exposures and short exposures between any two age intervals from 0 to 110, and for various radon concentrations found in homes from 50 to 1000 Bq/m3. The risk of developing lung cancer from residential radon exposure increases with radon concentration and exposure duration. For short exposure periods, such as 10 or 20 years, risks are higher in middle age groups (30-50) compared especially to the later years. Individuals could lower their risks significantly by reducing radon levels earlier in life. The tables could help radiation protection practitioners to better communicate indoor radon risk to members of the public.

  17. A Realistic Human Exposure Assessment of Indoor Radon released from Groundwater

    International Nuclear Information System (INIS)

    Yu, Dong Han; Han, Moon Hee

    2002-01-01

    The work presents a realistic human exposure assessment of indoor radon released from groundwater in a house. At first, a two-compartment model is developed to describe the generation and transfer of radon in indoor air from groundwater. The model is used to estimate radon concentrations profile of indoor air in a house using by showering, washing clothes, and flushing toilets. Then, the study performs an uncertainty analysis of model input parameters to quantify the uncertainty in radon concentration profile. In order to estimate a daily internal dose of a specific tissue group in an adult through the inhalation of such indoor radon, a PBPK(Physiologically-Based Pharmaco-Kinetic) model is developed. Combining indoor radon profile and PBPK model is used to a realistic human assessment for such exposure. The results obtained from this study would be used to the evaluation of human risk by inhalation associated with the indoor radon released from groundwater

  18. Educational project on risk communication and reduction of the radon exposure in buildings

    International Nuclear Information System (INIS)

    Conrady, J.; Guhr, A.; Uhlig, R.

    2009-01-01

    The radon exposure in buildings is supposed to be the most important risk factor of lung cancer. In Saxony about 800 000 persons live in apartments with high radon exposure. The study discusses the effects of an educational project to communicate the facts on radon exposure in buildings and to develop risk awareness and individual initiatives to reduce the radon concentration. The project includes support and encouragement with respect of preventive and protective measures to improve the individual situation. Further items cover requirements for control and quantification of intervention impacts, development and optimization of specific strategies for a permanent risk communication in schools. Results of the pilot study are summarized.

  19. Radon

    Energy Technology Data Exchange (ETDEWEB)

    Weigel, F [Muenchen Univ. (Germany, F.R.). Inst. fuer Anorganische Chemie

    1978-09-01

    The noble gas radon, formerly called emanation, was discovered a few years after radium. /sup 222/Rn, the longest-lived isotope, has a half-life of 3,82 days. This half life is so short that the experimental techniques available at present (1978) are not sufficient for a characterization of defined radon compounds, even though there are definite indications for the existence of such compounds, and one may expect such radon compounds to be even more stable than the numerous known xenon compounds. - The radon isotopes /sup 219/Rn (Actinon), /sup 220/Rn (Thoron), and /sup 222/Rn (Radon) occur in nature despite their rather short half-lives, because they are continously generated from their mothers /sup 223/Ra, /sup 224/Ra, and /sup 226/Ra, which are in secular equilibrium with long-lived isotopes /sup 235/U, /sup 238/U, and /sup 232/Th, and are in turn continously formed from these long-lived isotopes. Since the radon isotopes are gases, they enter the atmosphere and are carried for long distances with air currents. - Because radon is so short-lived, its practical applications are rather limited. For medical applications, small sealed glass tubes filled with radon are used as radiation sources after the radon has decayed, because the whole series of Po-, Bi-, and Pb-isotopes of the radium decay chain are formed, whose penetrating radiation is useful for therapy. When solids are spiked with Ra isotopes, radon is evolved at a constant rate. On heating such solids, phase transitions show up by sudden increased radon evolution (Hahn's emanation method). - On the basis of nuclear theoretical calculations, there is hardly a chance for the discovery of a long-lived radon species. Therefore, major progress in radon chemistry is hardly to be expected in the near future.

  20. Elevated radon levels in buildings: an investigation of potential sources in Region V arising from energy-conserving practices

    International Nuclear Information System (INIS)

    May, H.A.

    1979-01-01

    Some trends in single dwelling construction, and the resulting possibility of increased radiation exposure from radon progeny to the inhabitants, are identified. The number of such dwellings available and convenient for an ANL study is estimated. Preliminary measurements are reported

  1. Radon and its short-lived decay nuclides in the living environment

    International Nuclear Information System (INIS)

    Abe, Siro

    1988-01-01

    The problem about radon and its shortlived decay nuclides in the living environment has been frequently closed-up. The problem is focused on the exposure of human being due to radon and its progeny. This paper reports the reason to the occurrence of the problem. Radon source as well as its pathway into our rooms are outlined here. The behavior of radon and its progeny indoors is also shown in this paper in comparison with outdoor situation and from the persons' activity's point of view. (author)

  2. Environmental radon dosimetry in Indian dwellings and workplaces

    Energy Technology Data Exchange (ETDEWEB)

    Kant, K. [K.L.Mehta Dayanand College for Women, Dept. of Physics, Haryana (India); Upadhyay, S.B. [B.S.A. College, Dept. of Physics, Mathura, (India)

    2006-07-01

    Measurements of radon and its progeny in the dwellings and environment of workplaces are important because the radiation dose to human population due to inhalation of radon and its progeny contribute more than 50% of the total dose from natural sources and is the second leading cause of lung cancer after smoking. Recent experimental and epidemiological studies suggest that inhalation of radon progeny, which are the most important source of irradiation of the human respiratory track in workplace and domestic environment could be a cause of lung cancer. The quantification of iidual radon exposure over a long time period is one of the main issues. In the present study, we will report the results of radon monitoring carried out in the environment of workplaces of an oil refinery, LPG bottling plant, thermal power plant and gas power plant, besides the typical and modern Indian dwellings using alpha sensitive L.R.-115 type II solid-state nuclear track detectors in order to quantify the dose to the workers and the inhabitants. For comparison, the radon and its progeny levels were also measured in dwellings far away from the plants. Radon and its progeny levels were found higher in the environment of workplaces and dwellings in the vicinity of the plants. The details of the results obtained will be reported in the full paper. (authors)

  3. Environmental radon dosimetry in Indian dwellings and workplaces

    International Nuclear Information System (INIS)

    Kant, K.; Upadhyay, S.B.

    2006-01-01

    Measurements of radon and its progeny in the dwellings and environment of workplaces are important because the radiation dose to human population due to inhalation of radon and its progeny contribute more than 50% of the total dose from natural sources and is the second leading cause of lung cancer after smoking. Recent experimental and epidemiological studies suggest that inhalation of radon progeny, which are the most important source of irradiation of the human respiratory track in workplace and domestic environment could be a cause of lung cancer. The quantification of individual radon exposure over a long time period is one of the main issues. In the present study, we will report the results of radon monitoring carried out in the environment of workplaces of an oil refinery, LPG bottling plant, thermal power plant and gas power plant, besides the typical and modern Indian dwellings using alpha sensitive L.R.-115 type II solid-state nuclear track detectors in order to quantify the dose to the workers and the inhabitants. For comparison, the radon and its progeny levels were also measured in dwellings far away from the plants. Radon and its progeny levels were found higher in the environment of workplaces and dwellings in the vicinity of the plants. The details of the results obtained will be reported in the full paper. (authors)

  4. Epigenetic, histopathological and transcriptomic effects following exposure to depleted uranium in adult zebrafish and their progeny

    Energy Technology Data Exchange (ETDEWEB)

    Gombeau, Kewin, E-mail: kewin.gombeau@gmail.com [Institut de Radioprotection et de SÛreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Bourdineaud, Jean-Paul, E-mail: jean-paul.bourdineaud@u-bordeaux.fr [Université de Bordeaux, CNRS, UMR 5805, EPOC, 33400 Talence (France); Ravanat, Jean-Luc, E-mail: jean-luc.ravanat@cea.fr [Univ. Grenoble Alpes, INAC-SyMMES, 38000 Grenoble (France); CEA, INAC-SCIB Laboratoire des Lésions des Acides Nucléiques, 38000 Grenoble (France); Armant, Olivier, E-mail: olivier.armant@irsn.fr [Institut de Radioprotection et de SÛreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Camilleri, Virginie, E-mail: virginie.camilleri@irsn.fr [Institut de Radioprotection et de SÛreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Cavalie, Isabelle, E-mail: isabelle.cavalie@irsn.fr [Institut de Radioprotection et de SÛreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Floriani, Magali, E-mail: magali.floriani@irsn.fr [Institut de Radioprotection et de SÛreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); and others

    2017-03-15

    Highlights: • The parental DU-exposure induced a significant transfer of uranium into eggs. • Du-exposed progeny exhibited a significant 2-fold increased DNA methylation level. • The transcriptomic response was deeply modified in the DU-exposed organisms. • DU-exposed adult and offspring presented significant histopathological injuries. - Abstract: This study investigated the effects of adult zebrafish exposure to a nominal concentration of 20 μg L{sup −1} of depleted uranium (DU) for six days upon DNA methylation, gene expression and the appearance of histopathological damage in their progeny. In the embryos at the 2–8 cell stage, the parental exposure induced significant DU accumulation, with levels seven times higher than those measured in the control embryos, but in larvae 96 h post-fertilisation (hpf), uranium concentration had already returned to a level identical to that of the control larvae. A significant two-fold increase in the global level of DNA methylation was observed in embryos as early as the prim5 (24 hpf) stage and was still maintained at the 96 hpf stage despite the fact that DU had already been depurated at the later stage. RNA sequencing analysis indicated an impact of parental exposure upon the total RNAs transmitted from the mother to eggs, and the up-regulated genes were those associated with post-traductional protein modification and trafficking and cellular signalling pathways, whereas the down-regulated genes concerned the translational process, cell cycle regulation and several cell signalling pathways. Alterations of photoreceptor cells and the axon-axon junctions between photoreceptors were observed in the eyes of adult fish exposed for 10 days to DU. Actin and myosin filament disorganisation was observed in the skeletal muscles of 96 hpf larvae, at a stage when the maternally transmitted DU had already been excreted. These data reveal the extreme sensitivity of zebrafish embryos to DU transmitted through the oocyte by

  5. Epigenetic, histopathological and transcriptomic effects following exposure to depleted uranium in adult zebrafish and their progeny

    International Nuclear Information System (INIS)

    Gombeau, Kewin; Bourdineaud, Jean-Paul; Ravanat, Jean-Luc; Armant, Olivier; Camilleri, Virginie; Cavalie, Isabelle; Floriani, Magali

    2017-01-01

    Highlights: • The parental DU-exposure induced a significant transfer of uranium into eggs. • Du-exposed progeny exhibited a significant 2-fold increased DNA methylation level. • The transcriptomic response was deeply modified in the DU-exposed organisms. • DU-exposed adult and offspring presented significant histopathological injuries. - Abstract: This study investigated the effects of adult zebrafish exposure to a nominal concentration of 20 μg L −1 of depleted uranium (DU) for six days upon DNA methylation, gene expression and the appearance of histopathological damage in their progeny. In the embryos at the 2–8 cell stage, the parental exposure induced significant DU accumulation, with levels seven times higher than those measured in the control embryos, but in larvae 96 h post-fertilisation (hpf), uranium concentration had already returned to a level identical to that of the control larvae. A significant two-fold increase in the global level of DNA methylation was observed in embryos as early as the prim5 (24 hpf) stage and was still maintained at the 96 hpf stage despite the fact that DU had already been depurated at the later stage. RNA sequencing analysis indicated an impact of parental exposure upon the total RNAs transmitted from the mother to eggs, and the up-regulated genes were those associated with post-traductional protein modification and trafficking and cellular signalling pathways, whereas the down-regulated genes concerned the translational process, cell cycle regulation and several cell signalling pathways. Alterations of photoreceptor cells and the axon-axon junctions between photoreceptors were observed in the eyes of adult fish exposed for 10 days to DU. Actin and myosin filament disorganisation was observed in the skeletal muscles of 96 hpf larvae, at a stage when the maternally transmitted DU had already been excreted. These data reveal the extreme sensitivity of zebrafish embryos to DU transmitted through the oocyte by exposed

  6. Dosimetry of radon, thorium and their progenies in the environment of a chemistry lab and crude in Zulia State, Venezuela

    International Nuclear Information System (INIS)

    Pineda, L.; Viloria, T.; Palacios, D.; Sajo-Bohus, L.

    2013-01-01

    The main objective of this study was to estimate the dose rate of inhalation and the annual contribution of effective dose in the mixed field of radon and thoron in the environment of laboratory chemicals and oil from Zulia State, Venezuela, due to manipulation and storage of oil samples and water production

  7. Scopingreport radon

    International Nuclear Information System (INIS)

    Blaauboer, R.O.; Vaas, L.H.; Hesse, J.M.; Slooff, W.

    1989-09-01

    This report contains general information on radon concerning the existing standards, sources and emissions, the exposure levels and effect levels. lt serves as a basis for the discussion during the exploratory melting to be held in November/December 1989, aimed at determining the contents of the Integrated Criteria Document Radon. Attention is focussd on Rn-222 (radon) and Rn-220 (thoron), presently of public interest because of radon gas pollution in private homes. In the Netherlands air quality standards nor product standards for the exhalation rate of building materials have been recommended. The major source of radon in the Netherlands is the soil gas (> 97%), minor sources are phosphate residues and building materials (> 2% in total). Hence, the major concern is the transfer through the inhalation of air, the lung being the most critical organ at risk to develop cancer. Compared to risks for humans, the risks of radon and its daughters for aquatic and terrestric organisms, as well as for agricultural crops and livestock, are assumed to be limited. In the Netherlands the average dose for man due to radon and thoron progeny is appr. 1.2 mSv per year, the estimated dose range being 0.1-3.5 mSv per year. This dose contributes for about 50% to rhe total exposure due to all sources of ionizing radiation. Of this dose respectively 80% is caused by radon and about 90% is received indoor. The estimated dose for the general population corresponds to a risk for inducing fatal cancers of about 15 x 10-6 per year, ranging from 1.2 x 10-6 to 44 x 10-6 which exceeds the risk limit of 1 x 10-6 per year -as defined in the standardization policy in the Netherlands for a single source of ionizing radiation-with a factor 15 (1- 44). Reduction of exposure is only possible in the indoor environment. Several techniques have been described to reduce the indoor dose, resulting from exhalation of the soil and building materials. )aut- hor). 37 refs.; 3 figs.; 8 tabs

  8. Internal Exposure of a Seoul Subway Passenger due to Radon Inhalation: Before and After PSD Installation

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Ji-Yong; Kim, Eun-Hee [Seoul National University, Seoul (Korea, Republic of)

    2015-05-15

    Radon is the major source of public exposure to natural radiation and is also known to cause lung cancer. Platform screen doors (PSD) were installed primarily for passenger's safety purposes. Radon concentration and aerosol distribution have been changed since PSD installation. In this study, we have assessed the annual effective dose of regular subway passengers, before and after PSD installation, by employing current available data on air concentration of radon in Seoul subways with aerosol size distributions taken into account. ICRP recommends that the reference value for internal dose from radon be between 1.0 and 20.0 mSv. Korean Ministry of Environment enacted the indoor radon regulation, which requires the indoor radon level should not exceed 148 Bq/m{sup 3}. Radon concentrations in Seoul subways and annual dose estimates meet the requirements.

  9. Internal Exposure of a Seoul Subway Passenger due to Radon Inhalation: Before and After PSD Installation

    International Nuclear Information System (INIS)

    Shin, Ji-Yong; Kim, Eun-Hee

    2015-01-01

    Radon is the major source of public exposure to natural radiation and is also known to cause lung cancer. Platform screen doors (PSD) were installed primarily for passenger's safety purposes. Radon concentration and aerosol distribution have been changed since PSD installation. In this study, we have assessed the annual effective dose of regular subway passengers, before and after PSD installation, by employing current available data on air concentration of radon in Seoul subways with aerosol size distributions taken into account. ICRP recommends that the reference value for internal dose from radon be between 1.0 and 20.0 mSv. Korean Ministry of Environment enacted the indoor radon regulation, which requires the indoor radon level should not exceed 148 Bq/m 3 . Radon concentrations in Seoul subways and annual dose estimates meet the requirements

  10. Radon in workplaces

    International Nuclear Information System (INIS)

    Reichelt, A.; Lehmann, K.-H.; Reineking, A.; Porstendoerfer, J.; Schwedt, J.; Streil, T.

    2000-01-01

    The radiological assessment of the results of radon measurements in dwellings is not automatically applicable to workplaces due to different forms of utilization, constructional conditions, time of exposure, heating and ventilation conditions, additional aerosol sources, aerosol parameters, chemical substances, etc. In order to investigate the peculiarities of the radon situation in workplaces located inside buildings compared with that in dwellings, long-time recordings of radon, attached radon progeny and unattached radon progeny concentrations ( 218 Po, 214 Pb, 214 Bi) are carried out at several categories of workplaces (e.g. offices, social establishments, schools, production rooms, workshops, kitchens, agricultural facilities). 36 workplaces have been investigated. There have been carried out at least 2-3 long-time recordings for each workplace during different seasons. At the same time the gamma dose rate, meteorological conditions, aerosol particle concentrations have been registered. Many special dates from the workplaces and the buildings have been recorded. Activity size distribution of the aerosol-attached and unattached fraction of short-lived radon decay products have been determinated in 20 workplaces. Mainly the following measurement systems were used: Radon- and Radon Progeny Monitor EQF 3020, SARAD GmbH, Germany. Alpha-Track Radon Detectors, BfS Berlin, Germany. Screen Diffusion Batteries with Different Screens, University of Goettingen, Germany. Low-Pressure Cascade Impactor, Type BERNER. Condensation Nuclei Counter, General Electric, USA. PAEC-f p -Rn-Monitor, University of Goettingen, Germany. Through the measurements, many peculiarities in the course of the radon-concentration, the equilibrium factor F, the unattached fraction f p and the activity size distribution have been determined. These amounts are influenced mainly by the working conditions and the working intervals. The influence of these peculiarities in workplaces on the dose have

  11. Influence of radon daughter exposure rate, unattachment fraction, and disequilibrium on occurrence of lung tumours

    International Nuclear Information System (INIS)

    Cross, F.T.; Palmer, R.F.; Dagle, G.E.; Busch, R.H.; Buschbom, R.L.

    1984-01-01

    Groups of male, specific-pathogen-free (SPF), Wistar rats were exposed to several concentrations of radon daughters and uranium ore dust to clarify the roles of exposure rate, unattached RaA daughters, and the degree of radon daughter disequilibrium, in the development of respiratory system disease. Modelled, human dosimetric data indicate that the dose to sensitive tissues of the respiratory tract increases with increasing radon daughter unattachment fraction and degree of disequilibrium. Data bearing on these developments as well as updated results of experiments designed to test the role of radon daughter exposure rate on lung tumour incidence are reported. (author)

  12. Work to save dose: contrasting effective dose rates from radon exposure in workplaces and residences against the backdrop of public and occupational limits

    Energy Technology Data Exchange (ETDEWEB)

    Whicker, Jeffrey J [Los Alamos National Laboratory; Mcnaughton, Michael W [Los Alamos National Laboratory

    2009-01-01

    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 non-mine workplaces are lacking. Additionally, there are few, if any, comparative analyses of radon exposures at more 'typical' workplace with residential exposures within the same county. 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 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 8 times greater exposure at home than while in the office (2.3 mSv yr-! versus 0.3 mSv yr-!). The estimated effective dose rate for a more homebound person was about 3 mSv yr-!. Estimating effective doses from background radon exposure in the same county as Los Alamos National Laboratory, with thousands of'radiological workers,' highlights interesting contrasts in radiation protection standards that span public and occupational settings. For example, the effective dose rate from background radon exposure in unregulated office spaces ranged up to 1.1 mSv yr-!, which is similar to the 1 mSv yr-! threshold for regulation ofa 'radiological worker,' as defined in the Department of Energy regulations for occupational exposure. Additionally, the estimated average effective dose total of> 3 mSv yf! from radon background exposure in homes stands in

  13. Work to save dose: contrasting effective dose rates from radon exposure in workplaces and residences against the backdrop of public and occupational limits

    International Nuclear Information System (INIS)

    Whicker, Jeffrey J.; Mcnaughton, Michael W.

    2009-01-01

    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 non-mine workplaces are lacking. Additionally, there are few, if any, comparative analyses of radon exposures at more 'typical' workplace with residential exposures within the same county. 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 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 8 times greater exposure at home than while in the office (2.3 mSv yr- versus 0.3 mSv yr-). The estimated effective dose rate for a more homebound person was about 3 mSv yr-. Estimating effective doses from background radon exposure in the same county as Los Alamos National Laboratory, with thousands of'radiological workers,' highlights interesting contrasts in radiation protection standards that span public and occupational settings. For example, the effective dose rate from background radon exposure in unregulated office spaces ranged up to 1.1 mSv yr-, which is similar to the 1 mSv yr- threshold for regulation ofa 'radiological worker,' as defined in the Department of Energy regulations for occupational exposure. Additionally, the estimated average effective dose total of> 3 mSv yf from radon background exposure in homes stands in contrast to the 0.1 mSv yr- air pathway

  14. Radon problem in uranium industry

    International Nuclear Information System (INIS)

    Khan, A.H.; Raghavayya, M.

    1991-01-01

    Radon emission is invariably associated with the mining and processing of uranium ores. Radon (sup(222)Rn) enters mine atmosphere through diffusion from exposed ore body, fractures and fissures in the rocks and is also brought in by ground water. Being the progenitor of a series of short lived radioisotopes it contributes over 70% of the radiation dose to mine workers and thus accounts for nearly 30% of the total radiation doses received by workers in the whole nuclear industry. This paper summarises the data on radon emanation from the ore body, backfilled sands and mine water. Radon and its progeny concentrations in different haulage levels and stopes of the Jaduguda uranium mine are presented to emphasise the need for a well planned ventilation system to control radiation exposure of miners. Results of radon monitoring from a few exploratory uranium mines are included to indicate the need for a good ventilation system from inception of the mining operations. Relative contribution of mine exhaust and tailings surfaces to the environmental radon are also given. Some instruments developed locally for monitoring of radon and its progeny in mines and in the environment are briefly described to indicate the progress made in this field. (author). 17 refs., 2 figs., 6 tabs

  15. Calculation of lung cancer incidence in the Netherlands by smoking and radon exposure. Implications for the effect of radon

    International Nuclear Information System (INIS)

    Leenhouts, H.P.; Brugmans, J.P.

    2001-01-01

    Although the main cause of lung cancer is smoking cigarettes, part of the cases are subscribed to radon exposure, in particular α-radiation from daughter products. However, the relation between lung cancer and radon exposure is rather insecure. Based on international reports (e.g. BEIR VI) and extrapolation of lung cancer incidence in uranium mine workers to the population of the USA and subsequently to the Netherlands, the number of lung cancer cases in the Netherlands is estimated to be circa 800 per year, varying between 200-2000. Results of the analysis are summarized in this article. 10 refs

  16. Strategy for the assessment of the radiation exposure at workplaces due to radon and radon decay products

    International Nuclear Information System (INIS)

    Czarwinski, R.; Lehmann, R.

    1996-01-01

    According to the future EU basic standards the exposures to radon decay products have to be taken into consideration. Therefore it is necessary to investigate: * which working operation could be connected with an increased exposure to radon decay products, * which workplaces have to be considered, * how many employees could be afflicted, * which methods should be applied for the investigation and - as for as necessary - for supervision. On the basis of the current radiation protection legislation in the new Federal Lands working operations which are connected with radon exposures have already been monitored. For instance, in 1994 3095 persons were supervised, 2422 of them were engaged in clean-up operations at wismut facilities (including underground work) and 673 at non-uranium mines and facilities (conventional mining), water treatment plants, show caves and spas. The extension of the monitoring to similar workplaces in the old Federal Lands is going to discussed in implementation of the EU standards. Beyond it further workplaces affected by radon and radon decay products exist. Therefore it is helpful to get an overview about the kinds of workplaces and the number of afflicted employees. (author)

  17. Evaluation of the external exposure to Rn-222 progeny in air

    International Nuclear Information System (INIS)

    Ali, E.M.; Taha, T.M.; Gomaa, M.A.; El-Hussein, A.M.; Ahmed, A.A.

    2003-01-01

    The aim of this paper is to evaluate the Rn-222 progeny annual effective dose, skin dose and effective doses to different organs such as Gonad, Lung, Red Marrow, Bone surface, Thyroid, and the Remainder. Dose Coefficients of external exposure to Rn-222 in air was used in mSv s/Bqm -3 to calculate the organ doses. The study was monitored for two places, Nuclear Research Center and Al-Minia University. We have confirmed that the inhalation modes, sleep, sitting, light and heavy exercise influence the activity inhalation rate Bq/hr. It varies from 0.3 to 39.6 Bq/hr., the organ doses of Pb-214 is higher than Bi-214/Po-214 and Po-218 respectively in the case of the organ dose relative to environmental media

  18. BEIR VI report. Public summary: the health effects of exposure to indoor radon

    International Nuclear Information System (INIS)

    1998-01-01

    For centuries it has been known that some underground miners suffered from higher rates of lung cancer than the general population. In recent decades, a growing body of evidence has casually linked their lung cancers to exposure to high levels of radon and also to cigarette smoking. The connection between radon and lung cancer in miners has raised concern that radon in homes might be causing lung cancer in the general population, although the radon levels in most homes are much lower than in most mines. The National Research Council study, which has been carried out by the sixth Committee on Biological Effects of Ionizing Radiations (BEIR VI), has used the most recent information available to estimate the risks posed by exposure to radon in homes. The most direct way to assess the risks posed by radon in homes is to measure radon exposures among people who have lung cancer and compare them with exposures among people who have not developed lung cancer. Several such studies have been completed, and several are under way. The studies have not produced a definitive answer, primarily because the risk is likely to be very small at the low exposure encountered from most homes and because it is difficult to estimate radon exposures that people have received over their lifetimes. In addition, it is clear that far more lung cancers are caused by smoking that are caused by radon. The risk of lung cancer caused by smoking is much higher than the risk of lung cancer caused by indoor radon. Most of the radon-related deaths among smokers would not have occurred if the victims had not smoked. Furthermore, there is evidence for a synergistic interaction between smoking and radon. In other words, the number of cancers induced in ever-smokers by radon is greater than one would expect from the additive effects of smoking along and radon alone. Nevertheless, the estimated 15400 or 21800 deaths attributed to radon in combination with cigarette-smoking and radon alone in never

  19. Levels of thoron and progeny in high background radiation area of southeastern coast of Odisha (India))

    International Nuclear Information System (INIS)

    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.

    2012-01-01

    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. (authors)

  20. Levels of thoron and progeny in high background radiation area of southeastern coast of Odisha (India))

    Energy Technology Data Exchange (ETDEWEB)

    Ramola, R C; Gusain, G S; Rautela, B S [Dept. of Physics, H.N.B. Garhwal Univ., Badshahi Thaul Campus, Tehri Garhwal 249199 (India); Sagar, D V [Health Physics Unit EAD, BARC, IRE, OSCOM, Matikhalo, Ganjam, Odisha 761 045 (India); Prasad, G; Shahoo, S K; Ishikawa, T; Omori, Y; Janik, M [National Inst. of Radiological Sciences, Anagawa 4-9-1, Inage-ku, Chiba 263-8555 (Japan); Sorimachi, A; Tokonami, S [Inst. of Radiation Emergency Medicine, Hirosaki Univ., Aomori 036-8564 (Japan)

    2012-07-01

    Exposure to radon, {sup 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, {sup 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 {sup 220}Rn and its progeny can equal or several time exceed that of {sup 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. (authors)

  1. The use of SSNTDs in the retrospective assessment of radon exposure in high radon rural communities in Yugoslavia

    CERN Document Server

    Zunic, Z S; Walsh, C; Benderac, R

    1999-01-01

    A description is given of the field application of a technique using CR-39 and LR 115 detectors to determine alpha recoil implanted sup 2 sup 1 sup 0 Po surface activity on domestic glass artefacts in dwellings. These investigations took place in two small stable rural communities in uraniferous areas of Yugoslavia where between 32% and 74% of contemporary indoor radon levels were found to be above the commonly used Action Level of 200 Bq m sup - sup 3 and individual levels as high as 8700 Bq m sup - sup 3 were measured. The sup 2 sup 1 sup 0 Po data is used to retrospectively estimate radon exposures in these communities. Comparisons between the retrospectively estimated radon exposures and those being received at present are made.

  2. Radon studies in selected workplaces

    International Nuclear Information System (INIS)

    Randle, M.W.

    2000-01-01

    Radon progeny levels were measured in coal mines, a hard rock mine and two underground hydro power stations, to indicate if there is a health problem associated with exposure to radon and radon progeny in these workplaces. The average alpha concentrations ranged from 37 to 276 Bq m -3 , with the highest levels being found in a mine with no ventillation that was being decommissioned. Average dosages were calculated to be 0.1 - 0.7 mSv y -1 . Radon progeny levels in coal mines measured in the return air circuit are indicative of levels to which a worker at the face would be exposed. They were well below international guidelines for intervention in New Zealand mines, as were the slightly higher levels in two underground hydro power stations. These results confirm that radon levels in New Zealand are low. Even in the extreme situation represented by the Sullivan mine with no ventillation the levels do not warrant concern. 11 refs., 2 tabs

  3. Slovenian approach in managing exposure to radon at workplaces

    International Nuclear Information System (INIS)

    Vaupotic, J.

    2010-01-01

    Radon was surveyed in all the kindergartens and schools, major hospitals, water plants, wineries, spas, in a number of other public buildings, and karst caves with emphasis on the Postojna Cave (Slovenia). In addition to radon, also the concentration of radon short-lived decay products, equilibrium factor between radon and decay products, and unattached fraction of decay products have been monitored. Effective doses were calculated and used as a criterion to require remediation. (author)

  4. Exposure to radon in dwellings: risk assessment and management. Health and Society Collection nr 8

    International Nuclear Information System (INIS)

    Bard, Denis; Jouan, Michel; Lochard, Jacques; Festy, Bernard; Piechowski, Jean; Sauvalle, Bertrand; Tymen, Georges; Masse, Roland; Monchaux, Georges; Tirmarche, Margot; Boice, John D.; Cohen, Bernard L.; Hubert, Philippe; Pirard, Philippe; Zmirou, Denis; Lefaure, Christian; Poffijn, Andre; Van Nuffelen, Dominique; Chayapathi, Laksmhi; Thevissen, Frank; Eggermont, Gilbert; Massuelle, Marie-Helene; Robe, Marie-Christine; Grassin, Delphine; Collignan, Bernard; Millet, Jean-Robert; Cochet, Christian; Mansotte, Francois; Dab, William; Gilbert, Claude; Richert, Philippe; Charreyron, Bruno; Kalifa, Gabriel; Chartier, Philippe; FReMAUX, ELIANE; Jean-Louis Decossas; Andru, M.; Bernard, Sylvain; Bonnefoy, Xavier

    2000-04-01

    The contributions of this colloquium propose reports issues related to radon and on practices of neighbouring countries in radon risk assessment and management, on the management of the environmental risk and of public information at the district level in France, on situations involving not only radon but also some other potentially toxic agents (problems of indoor air quality), and on problems other than health problems which could emerge while implementing prevention or mitigating measures related to radon. After a general presentation of radon (Georges Tymen), a first set of contributions addresses the identification of hazards: Carcinogenesis and ionizing radiations put in question again (Roland Masse); Data from animal experimentation on radon (Georges Monchaux); Epidemiology of the radon risk in France (Margot Timarche); Joint analysis of underground miners and risks of radon-induced lung cancer (John D. Boice); Studies of the geographic correlation of radon risk (Bernard L. Cohen). The second set of contributions addresses the building up of an exposure-risk relationship: Why and how to build up dose-effect relationship? Approaches by international institutions (Philippe Hubert); Extrapolation of the dose-response relationship for public health evaluation (John D. Boice). A contribution addressed Exposures and risk assessment in France (Philippe Pirard). A synthesis on stakes in then proposes (Denis Zmirou). The last set of contributions addressed the analysis of management options: Management of the radon-related radiological risk in dwellings (Christian Lefaure); Reflections on the perception and communication of the radon risk (Gilbert Eggermont); Exposure boundary values? Alternatives and practical information (Marie-Helene Massuelle); Practical ways of action in present housing and costs (Marie-Christine Robe, Jean-Robert Millet); Management of the radon problem within a global perspective of indoor air quality (Christian Cochet); Risk management and

  5. UK standards for exposure to radon daughters in dwellings

    International Nuclear Information System (INIS)

    Webb, G.A.M.; O'Riordan, M.C.

    1988-01-01

    The National Radiological Protection Board has issued formal advice on the standards to be adopted in the UK for control of exposures to radon daughters in existing dwellings and for changes in building procedures for future dwellings. The standards are based on those recommended by the International Commission on Radiological Protection but adapted to circumstances in the United Kingdom. The matters taken into account by the Board when formulating its advice include the conversion from measured concentrations of radon to effective dose equivalent and the implied levels of risk, the comparison of these levels with risks from other causes, the numbers of dwellings in which various annual doses are likely to be exceeded, the geographical distribution of these dwellings, the likely costs and effectiveness of various remedial measures and the degree of domestic disruption. The action level for existing dwellings selected by the Board was the same, 20 mSv per annum, as that recommended by the ICRP, but the upper bound for new dwellings of 5 mSv per annum was lower than that suggested by the ICRP

  6. UK standards for exposure to radon daughters in dwellings

    International Nuclear Information System (INIS)

    Webb, G.A.M.; O'Riordan, M.C.

    1988-01-01

    The National Radiological Protection Board has issued formal advice on the standards to be adopted in the UK for control of exposures to radon daughters in existing dwellings and for changes in building procedures for future dwellings. The standards are based on those recommended by the international commission on radiological protection but adapted to circumstances in the United Kingdom. The matters taken into account by the Board when formulating its advice, and which are discussed in the paper, include the conversion from measured concentrations of radon to effective dose equivalent and the implied levels of risk, the comparison of these levels with risks from other causes, the numbers of dwellings in which various annual doses are likely to be exceeded, the geographical distribution of these dwellings, the likely costs and effectiveness of various remedial measures and the degree of domestic disruption. The action level for existing dwellings selected by the Board was the same, 20 mSv per annum, as that recommended by the ICRP, but the upper bound for new dwellings of 5 mSv per annum was lower than that suggested by the ICRP [fr

  7. On the influence of environmental factors on radon levels in caves of Ribeira valley state parks, SP and evaluation of radioactive equilibrium and equilibrium factor between radon and its progeny

    International Nuclear Information System (INIS)

    Alberigi, Simone

    2011-01-01

    In the present study it was carried out the monitoring of radon in caves distributed among three state parks of Sao Paulo. The radon concentration were determinate in Morro Preto and Santana caves, located at PETAR - Parque Estadual Turistico do Alto Ribeira (High Ribeira River Tourist State Park), Diabo cave, situated in PEJ - Parque Estadual de Jacupiranga (Jacupiranga State Park) and Colorida cave located in PEI - Parque Estadual Intervales (Intervales State Park PEI). The monitoring covered measurements between April 2009 and June 2010. Radon concentrations were carried out by using the technique of passive detection with CR-39 solid state nuclear track detectors and NRPB diffusion chambers. The detectors were exposed in periods ranging from 30 to 150 days. Radon concentrations varied from 132 Bq/m 3 to 9456 Bq/m 3 . The values of radon concentrations were analyzed together with information about rainfall and internal and external temperature values of the Santana cave environment and regional literature values for a possible relationship between radon variations and weather information. Both the determinations of 22 '6Ra in water samples collected in some caves and rivers and radon emanation from a stalactite collected at Santana cave allowed to verify that the radon in the caves comes from the walls rocks. The verification of the radioactive equilibrium between 222 Rn, 218 Po and '2 14 Po in the exposed detectors was prejudiced by the high tracks densities, committing the methodology effectiveness. The annual effective dose was calculated for three values obtained from the literature for the equilibrium factor. Considering the most realistic scenario, with equilibrium factor of 0.5 and 52 working weeks, the annual effective dose was 5.1 mSv/y. Concerning the worst scenario, which simulates an extreme case, adopting an equilibrium factor equal to 1 and 52 weeks of work per year, the annual effective dose is 10.2 mSv/y. Also with information received from a

  8. The ratio of long-lived to short-lived radon-222 progeny concentrations in ground-level air

    Energy Technology Data Exchange (ETDEWEB)

    Hoetzl, H.; Winkler, R. [Institut fuer Strahlenschutz, GSF-Forschungszentrum fuer Umwelt und Gesundheit, Neuherberg Oberschleissheim (Germany)

    1996-02-09

    The ratio of {sup 210}Pb air concentration to the short-lived radon ({sup 222}Rn) decay products concentration at ground level was investigated at a semi-rural location 10 km north of Munich, south Germany, for a period of 11 years (1982-1992). The average ratio from 132 monthly mean values has been found to be (7.5{+-}2.2) x 10{sup -5} (arithmetic mean{+-}S.D.). While the time series of the short-lived radon daughter concentration exhibit a distinct seasonal pattern with maxima mostly in October of each year, the course of {sup 210}Pb air concentration is characterized by high values from October through February. Consequently, high ratios of {sup 210}Pb to short-lived decay product concentration are often observed in the winter months of December-February. To study the influence of meteorological conditions on this behaviour, {sup 210}Pb and {sup 214}Pb concentrations were measured on a short-term basis with sampling intervals of 2-3 days from October 1991 to November 1992. The air concentrations obtained within those intervals were then correlated with actual meteorological parameters. On the base of this investigation the seasonal behaviour can essentially be explained by the more frequent inversion weather conditions in winter than in the summer months. At the same location, the average ratio of {sup 210}Po to {sup 210}Pb concentration in ground level air has been found to be 0.079 from 459 weakly mean values between 1976 and 1985. Hence, the corresponding average ratios of the short-lived radon daughters (EEC) to {sup 210}Pb and {sup 210}Po, were 1:7.5x10{sup -5} and 1:0.6 x 10{sup -5}, respectively.

  9. The ratio of long-lived to short-lived radon-222 progeny concentrations in ground-level air

    International Nuclear Information System (INIS)

    Hoetzl, H.; Winkler, R.

    1996-01-01

    The ratio of 210 Pb air concentration to the short-lived radon ( 222 Rn) decay products concentration at ground level was investigated at a semi-rural location 10 km north of Munich, south Germany, for a period of 11 years (1982-1992). The average ratio from 132 monthly mean values has been found to be (7.5±2.2) x 10 -5 (arithmetic mean±S.D.). While the time series of the short-lived radon daughter concentration exhibit a distinct seasonal pattern with maxima mostly in October of each year, the course of 210 Pb air concentration is characterized by high values from October through February. Consequently, high ratios of 210 Pb to short-lived decay product concentration are often observed in the winter months of December-February. To study the influence of meteorological conditions on this behaviour, 210 Pb and 214 Pb concentrations were measured on a short-term basis with sampling intervals of 2-3 days from October 1991 to November 1992. The air concentrations obtained within those intervals were then correlated with actual meteorological parameters. On the base of this investigation the seasonal behaviour can essentially be explained by the more frequent inversion weather conditions in winter than in the summer months. At the same location, the average ratio of 210 Po to 210 Pb concentration in ground level air has been found to be 0.079 from 459 weakly mean values between 1976 and 1985. Hence, the corresponding average ratios of the short-lived radon daughters (EEC) to 210 Pb and 210 Po, were 1:7.5x10 -5 and 1:0.6 x 10 -5 , respectively

  10. Radon-thoron exposures in high background radiation areas: a review

    International Nuclear Information System (INIS)

    Nambi, K.S.

    1994-01-01

    The radon-thoron measurements reported in literature for the high background radiation areas (HBRAs) of the world are summarised here. The most important areas covered are the Radon Spas and the thorium bearing monazite deposits. Special mention is made of the ongoing programmes of radon-thoron survey in the monazite beach areas of India; preliminary measurements indicate significant levels of thoron exposures. The diurnal and seasonal variations are quite wide underscoring the importance of carrying out integrated measurements for meaningful assessments of population exposures. Radon-thoron inhalation dose rates upto 30 mSv/y have been measured in lran as well as India. It has been generally observed that the cumulative population doses due to radon-thoron inhalation are as high as those due to the external exposures in these HBRAs. (author). 7 refs., 2 tabs., 3 figs

  11. Lung cancer incidence after smoking and exposure to radon using a two-mutation model

    International Nuclear Information System (INIS)

    Leenhouts, H.P.

    1997-01-01

    A study to analyze lung cancer in humans as a function of exposure to radon and smoking, used three types of data: population statistics in non-smokers habits of British radiologists and radon exposure of the Colorado uranium miners. Using a simplified two-mutation carcinogenesis model and only six unknown variables yielded a coherent description of lung cancer dependence on exposure to radon and smoking. For risk estimates the radiation effect of radon can be concluded to be highly dependent on smoking habits, e.g. the radiation effect differs (in absolute terms) by a factor of about 7 between non-smokers, but the relative risk is much higher in non-smokers than in smokers. The results to data justify a thorough investigation of the analysis method to realize improved radon risk estimates. (author)

  12. Lung cancer incidence after smoking and exposure to radon using a two-mutation model

    Energy Technology Data Exchange (ETDEWEB)

    Leenhouts, H.P. [RIVM, Bilthoven (Netherlands)

    1997-03-01

    A study to analyze lung cancer in humans as a function of exposure to radon and smoking, used three types of data: population statistics in non-smokers habits of British radiologists and radon exposure of the Colorado uranium miners. Using a simplified two-mutation carcinogenesis model and only six unknown variables yielded a coherent description of lung cancer dependence on exposure to radon and smoking. For risk estimates the radiation effect of radon can be concluded to be highly dependent on smoking habits, e.g. the radiation effect differs (in absolute terms) by a factor of about 7 between non-smokers, but the relative risk is much higher in non-smokers than in smokers. The results to data justify a thorough investigation of the analysis method to realize improved radon risk estimates. (author)

  13. The radon issue: Considerations on regulatory approaches and exposure evaluations on the basis of recent epidemiological results

    International Nuclear Information System (INIS)

    Bochicchio, Francesco

    2008-01-01

    Recent epidemiological results have shown consistent statistically significant increases of lung cancer risk due to exposure to radon in dwellings at moderate levels of exposure, and a strong synergism with cigarette smoking. These results are summarized and discussed in relation to their possible implications for the regulatory control of radon and for future policies for the control of radon risk

  14. Effects of Radon and UV Exposure on Skin Cancer Mortality in Switzerland

    NARCIS (Netherlands)

    Vienneau, Danielle; de Hoogh, Kees; Hauri, Dimitri D.; Vicedo-Cabrera, Ana M; Schindler, Christian; Huss, Anke; Röösli, Martin

    2017-01-01

    BACKGROUND: Skin cancer incidence in Switzerland is among the highest in the world. In addition to exposure to ultraviolet (UV) radiation, radon alpha particles attached to aerosols can adhere to the skin and potentially cause carcinogenic effects. OBJECTIVES: We investigated the effects of radon

  15. The unintentional and unconscious exposure to radon (and other natural radionuclides)

    International Nuclear Information System (INIS)

    Thomas, J.

    1998-01-01

    The radon programmes for dwellings (remediation of the risk and prevention of the risk) as well as radon programmes for workplaces in the Czech Republic are described. To implementation radiation protection against natural radiation sources on workplaces with unintentional and unconscious exposure to these sources of radiation is a new, but interesting and important task which need new approaches, time staff and effort

  16. Cigarette smoking increases radon working level exposures to all occupants of the smoker's home

    International Nuclear Information System (INIS)

    Johnson, R.H. Jr.; Rosario, A. Jr.

    1990-01-01

    This paper reports that the 1988 National Academy of Sciences report on radon health risks evaluated the combined effects of radon exposures and cigarettes on the lung cancer risk to smokers. This report showed that the risk of lung cancer is about 10 times greater for smokers than for nonsmokers at the same Working Level exposures. In 1986, the Surgeon General reported that 106,000 lung cancer deaths occurred among smokers. Therefore, the health risks of cigarettes alone or in combination with radon exposures are well recognized. What has not been studied is the effect of cigarette smoke on the Working Levels in homes that increases the exposure to radon decay products to all occupants, both smokers and nonsmokers. Preliminary studies in a radon chamber at Radon QC showed that the smoke from a single cigarette increased the Working Levels by a factor of five within four hours. Furthermore, the Working Levels remained at an elevated level for more than 24 hours. The equilibrium ratio of radon decay products to radon gas also went from about 14% up to 71%, with a slow decrease over 24 hours. Similar studies in the homes of a smoker and nonsmoker confirmed the laboratory observations. The studies in homes also showed the effects of thoron decay products

  17. estimation of the sanitary impact associated to the domestic exposure to radon in Franche-Comte

    International Nuclear Information System (INIS)

    Catelinois, O.; Pirard, P.; Clinard, F.; Aury, K.; Tillier, C.; Aury, K.; Noury, L.; Hochard, A.

    2008-01-01

    The importance of the impact of public health associate to domestic radon exposure in Franche-Comte is clearly formulated. The radon concentrations are higher in the granite areas. However, the impact is essentially concentrated in the Franche-Comte sedimentary areas where the essential of the population lives. (N.C.)

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

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    Semler, M.O.; Sensintaffar, E.L. [National Air and Radiation Environmental Laboratory, Montgomery, AL (United States)

    1993-12-31

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

  20. Radon Exposure and the Definition of Low Doses-The Problem of Spatial Dose Distribution.

    Science.gov (United States)

    Madas, Balázs G

    2016-07-01

    Investigating the health effects of low doses of ionizing radiation is considered to be one of the most important fields in radiological protection research. Although the definition of low dose given by a dose range seems to be clear, it leaves some open questions. For example, the time frame and the target volume in which absorbed dose is measured have to be defined. While dose rate is considered in the current system of radiological protection, the same cancer risk is associated with all exposures, resulting in a given amount of energy absorbed by a single target cell or distributed among all the target cells of a given organ. However, the biological effects and so the health consequences of these extreme exposure scenarios are unlikely to be the same. Due to the heterogeneous deposition of radon progeny within the lungs, heterogeneous radiation exposure becomes a practical issue in radiological protection. While the macroscopic dose is still within the low dose range, local tissue doses on the order of Grays can be reached in the most exposed parts of the bronchial airways. It can be concluded that progress in low dose research needs not only low dose but also high dose experiments where small parts of a biological sample receive doses on the order of Grays, while the average dose over the whole sample remains low. A narrow interpretation of low dose research might exclude investigations with high relevance to radiological protection. Therefore, studies important to radiological protection should be performed in the frame of low dose research even if the applied doses do not fit in the dose range used for the definition of low doses.

  1. Review of radon and lung cancer risk

    International Nuclear Information System (INIS)

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

    1990-01-01

    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

  2. A passive method for the determination of the equilibrium factor between radon gas and its short period progeny

    International Nuclear Information System (INIS)

    Lopez, Fabio O.; Canoba, Analia C.

    2001-01-01

    Due to the radiological importance of 222 Rn gas and its progeny of short period it is extremely necessary to count with an adequate methodology for the determination of its concentration in the different atmospheres in which human activity is developed. In this work a method was developed to determine the concentration of 222 Rn gas and the equilibrium factor between the concentration of the gas and its descendants, by means of a single device that has two Makrofol passive tracks detector. This device is completely passive and integrating, conditions that make it very appropriate to be used in any atmospheres in which human activity is developed, for example in houses, schools, places of work, underground mines, etc. (author)

  3. Assessment of radon exposure in Austria based on geology and settlement

    International Nuclear Information System (INIS)

    Gruber, Valeria; Seidel, Claudia

    2008-01-01

    In Austria a fundamental radon indoor data net (about 40 000 measurements) exists. These radon indoor data are standardized and provide averaged political communities' values. This data net should be enhanced by soil gas measurements with regard to geological conditions, to avoid averaging and influences by political boundaries. Different geological units (characterized by geology, geochemical conditions, mineralogy, geophysics) will be surveyed regarding radon concentration by soil gas measurements and estimated to their potential radon hazard. To assess the radon exposure of the population geological units are selected which are either existing settlement areas or potential ones. So this survey can also provide a basis for land use planning. In this paper results of first studies for this purpose are shown. 160 soil gas measurements were carried out in different soil and sediment deposits originating from different ice age glacier movements in the Alps. These deposits are popular settlement areas, and indoor radon levels of some 1000 Bq/l were detected. 50 % of the results of soil gas radon measurements were above 60 kBq/m 3 , 18 % above 120 kBq/m 3 , which is likely to exceed the indoor radon standard of 400 Bq/l according to the Austrian standard ONORM S 5280-2. Higher radon activity concentrations were found in older ice ages, because of further progressed weathering. The radon soil gas measurements were carried out in different seasons to verify seasonal variations, and other parameters like Ra-226, Ra-228 activity concentration in soils, radon emanation factor, soil permeability and soil moisture were determined and related to the radon activity concentration. According to the example of this study, further soil gas measurements will be carried out in selected geological units. Additional research on the impact of actual dwelling and inhabitation situation on public exposure due to radon in Austria is being done currently. The soil gas radon measurement data

  4. Internal exposure to 222Rn progeny of the underground workers in Bulgarian uranian mines in 1958-1989

    International Nuclear Information System (INIS)

    Dimitrov, M.; Presiyanov, D.

    1998-01-01

    The results of more than 50000 measurements of 222 Rn and 22R n progeny measurements made in 1958-1989 in 9 large Bulgarian uranium mines (namely: '9 septemvri', 'Seslavci', 'Eleshnitsa 1, 2, 3', 'Smolyan', 'Byalata voda', 'Balkan' and 'Smolyanovtsi') have been summarized. The average WLM-exposures have been determined for each of the mines. The results make possible to estimate internal WLM exposure of any miner, provided that his underground working experience is known

  5. A combined method for evaluating radon and progeny in waters and its use at Guarani aquifer, São Paulo State, Brazil.

    Science.gov (United States)

    Bonotto, D M; Mello, C B

    2006-01-01

    A combined method for evaluating radon (222Rn) and progeny (214Pb and 214Bi) in water was developed by using inexpensive alpha scintillation counting and gamma ray spectrometry through NaI(Tl) scintillation detectors. A groundwater sample collected at the Poços de Caldas alkaline massif in Brazil was submitted to the technique in order to assure its applicability by comparing the volumetric activities by different methods. Similar volumetric activity was determined for 214Pb and 214Bi in the sample analyzed that is compatible with the expected condition of radioactive equilibrium between these nuclides. The combined method was successfully used to analyze groundwater samples from Guarani aquifer in São Paulo State, Brazil, and the results of the measurements indicated that 214Pb and 214Bi provide useful information concerning the evaluation of the drinking water quality in terms of radiological aspects. This is because they are directly identified in the water samples, without the need of requiring the assumption of the establishment of the transient equilibrium condition with its parent 222Rn.

  6. Residential Radon Exposure and Incidence of Childhood Lymphoma in Texas, 1995–2011

    Directory of Open Access Journals (Sweden)

    Erin C. Peckham

    2015-09-01

    Full Text Available There is warranted interest in assessing the association between residential radon exposure and the risk of childhood cancer. We sought to evaluate the association between residential radon exposure and the incidence of childhood lymphoma in Texas. The Texas Cancer Registry (n = 2147 provided case information for the period 1995–2011. Denominator data were obtained from the United States Census. Regional arithmetic mean radon concentrations were obtained from the Texas Indoor Radon Survey and linked to residence at diagnosis. Exposure was assessed categorically: ≤25th percentile (reference, >25th to ≤50th percentile, >50th to ≤75th percentile, and >75th percentile. Negative binomial regression generated adjusted incidence rate ratios (aIRR and 95% confidence intervals (CI. We evaluated lymphoma overall and by subtype: Hodgkin (HL; n = 1248, Non-Hodgkin excluding Burkitt (non-BL NHL; n = 658, Burkitt (BL; n = 241, and Diffuse Large B-cell (DLBCL; n = 315. There was no evidence that residential radon exposure was positively associated with lymphoma overall, HL, or BL. Areas with radon concentrations >75th percentile had a marginal increase in DLBCL incidence (aIRR = 1.73, 95% CI: 1.03–2.91. In one of the largest studies of residential radon exposure and the incidence of childhood lymphoma, we found little evidence to suggest a positive or negative association; an observation consistent with previous studies.

  7. 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

    International Nuclear Information System (INIS)

    Nelson, I.C.

    1993-01-01

    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

  8. Assessment of radiation exposure to miners due to radon and radon daughters

    International Nuclear Information System (INIS)

    Przyborowski, S.

    1979-01-01

    An overview is given of the basic considerations regarding the establishment of lung limits for miners exposed to radon and radon daughters. Problems associated with the practical conduct of radiation protection monitoring are also dealt with, for example, the implications of temporal and local variations in activity levels to the mode of sampling and the interpretation of results. (author)

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

    International Nuclear Information System (INIS)

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

    2000-01-01

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

  10. Initial damage in human interphase chromosomes from alpha particles with linear energy transfers relevant to radon exposure

    International Nuclear Information System (INIS)

    Loucas, B.D.; Geard, C.R.

    1994-01-01

    To determine the efficiency at which α particles at LETs chosen to simulate exposure to radon progeny break chromosomes, the premature chromosome condensation technique was used to measure breaks soon after irradiation. Noncycling human fibroblasts were irradiated with graded doses of monoenergetic α particles accelerated to produce LETs of 90, 120, 150, 180 and 200 keV/pm at the midpoint of the cell nuclei. Premature chromosome condensation was initiated immediately after irradiation and cells were scored for the total number of prematurely condensed chromosomes and fragments per cell. Similar experiments were conducted with 250 kVp X rays for comparison. Irradiation with α particles produced 8.6 to 13.1 excess fragments per gray, while X rays produced 5.8 excess fragments, resulting in RBEs around 2. Calculations of the number of breaks produced on average by a single particle traversal of a cell nucleus indicated that at the LETs tested more than one break was produced by each traversal, the maximum being that produced by 180 keV/μm α particles. When chromosome aberrations are scored at metaphase after high-LET irradiation, RBEs considerably greater than those recorded here have been reported. These results showing relatively small differences in initial break levels for α particles in the LET range of the radon progeny relative to X rays indicate that the great aberration frequencies are not due principally to an increase in breakage efficiency, but interactions between breaks along the same particle track are important. 16 refs., 4 figs

  11. Radon

    International Nuclear Information System (INIS)

    Holmen, R.W.

    1987-01-01

    The discovery that radon enters into residential and commercial structures and produces adverse health consequences to occupants thereof has raised issues for the real estate profession in connection with transactions involving affected structures. The legal responsibilities of real estate professionals in relation to such structures have not yet been clearly defined. Moreover, consistent and reliable testing methods and results, clear identification of circumstances where testing is necessary, and consensus as to health risks suggested by various radon levels have yet to be achieved. When these legal and technical questions are clarified, real estate buyer and sellers as well as agents and brokers will be greatly benefited

  12. Characterization of the personal dosimeter Rn-disk for monitoring radon exposure

    International Nuclear Information System (INIS)

    Orlando, P.; Arcovito, G.; Amici, M.; Orlando, C.; Cardellini, F.; Fiorentino, A.; Trevisi, R.

    2009-01-01

    Rn-disk is a new passive device for measuring occupational exposure to radon 222, are presented the results of tests for the characterization of the dosimeter as a tool for estimating the individual dose for workers. [it

  13. Colloquium:exposure to radon in houses: evaluation and risk management

    International Nuclear Information System (INIS)

    Anon.

    1998-01-01

    In this article, one intends to develop elements describing the behaviour of radon and its daughters in atmosphere, while pointing out the physical parameters allowing to characterize the personal natural exposure ( alpha potential energy, equilibrium fraction). (N.C.)

  14. Indoor air radon

    International Nuclear Information System (INIS)

    Cothern, C.R.

    1990-01-01

    This review concerns primarily the health effects that result from indoor air exposure to radon gas and its progeny. Radon enters homes mainly from the soil through cracks in the foundation and other holes to the geologic deposits beneath these structures. Once inside the home the gas decays (half-life 3.8 d) and the ionized atoms adsorb to dust particles and are inhaled. These particles lodge in the lung and can cause lung cancer. The introduction to this review gives some background properties of radon and its progeny that are important to understanding this public health problem as well as a discussion of the units used to describe its concentrations. The data describing the health effects of inhaled radon and its progeny come both from epidemiological and animal studies. The estimates of risk from these two data bases are consistent within a factor of two. The epidemiological studies are primarily for hard rock miners, although some data exist for environmental exposures. The most complete studies are those of the US, Canadian, and Czechoslovakian uranium miners. Although all studies have some deficiencies, those of major importance include uranium miners in Saskatchewan, Canada, Swedish iron miners, and Newfoundland fluorspar miners. These six studies provide varying degrees of detail in the form of dose-response curves. Other epidemiological studies that do not provide quantitative dose-response information, but are useful in describing the health effects, include coal, iron ore and tin miners in the UK, iron ore miners in the Grangesburg and Kiruna, Sweden, metal miners in the US, Navajo uranium miners in the US, Norwegian niobian and magnitite miners, South African gold and uranium miners, French uranium miners, zinc-lead miners in Sweden and a variety of small studies of environmental exposure. An analysis of the epidemiological studies reveals a variety of interpretation problem areas.172 references

  15. Effect of smoking on the radon risk in dependence on the time elapsed from exposure

    International Nuclear Information System (INIS)

    Boehm, Radoslav; Holy, Karol; Sedlak, A.

    2013-01-01

    The synergistic effect of cigarette smoking and radon exposure on the lung cancer risk was assessed by using the threshold energy model, which allows the biological effects of radon daughter products on the lung tissue to be analyzed. The shape of the curves describing the relation between the risk and the time after exposure was estimated. The change in the lung function caused by chronic smoking was considered in the calculations. (orig.)

  16. The determination of airborne concentrations of radon and thoron progeny by repetitive alpha counting of filter samples

    International Nuclear Information System (INIS)

    French, Clayton S. Jr.; Skrable, Kenneth W.; Chabot, George E.

    1978-01-01

    Analytical equations have been used to determine the airborne concentrations of the particulate daughters of radon and thoron from five net alpha counts obtained at preset time intervals post sampling. The same expressions were used to propagate the associated standard deviations. These propagated errors were minimized by the selection of optimum sampling and counting intervals. An extensive error analysis examined sources of interference and their influence on the calculated concentrations. This system offers sufficient precision for research applications, yet is simple and inexpensive enough for application in field studies. The radon and thoron daughters measured with this technique are 218 Po, 214 Pb, 214 Bi, 212 Pb, and 212 Bi. Because of the decay kinetics involved, the calculated concentrations of 218 Po and 212 Bi involve the greatest uncertainty. The proper choice of sampling and counting intervals optimizes the system for any one of the above radionuclides or for all five collectively. A sampling time of 15 minutes is best for the simultaneous estimation of all five concentrations. Millipore filter samples were obtained from a large, unventilated sub-basement of the University of Lowell research reactor facility and were counted later in direct contact with the window of a gas flow proportional detector having alpha particle counting efficiencies near 0.4 ca -1 and an alpha background of about 1 c min -1 . A typical 15 minute sample obtained at a flow rate of 2 x 10 4 cm 3 min -1 yielded estimates of the airborne concentrations and relative standard deviations: 218 Po, 4.75 x 10 -9 μCi cm -3 ± 18.9%; 214 Pb, 5.15 x 10 -9 μCi cm -3 ± 2.5%; 214 Bi, 4.86 x 10 -9 μCi cm -3 ± 2.4%; 212 Pb, 1.41 x 10 -10 μCi cm -3 ± 2.0%; and 212 Bi, 2.15 x 10 -10 μCi cm -3 ± 27.0%. (author)

  17. Indoor radon level in schools of Shillong, Meghalaya

    International Nuclear Information System (INIS)

    Saxena, A.; Sharma, Y.; Maibam, D.; Walia, D.; Diengdoh, E.

    2010-01-01

    Radon ( 222 Rn) in the atmosphere is the most important contributor to human exposure from natural sources. Radon is a noble inert gas; and it decays to radionuclides that are chemically active and relatively short lived. Inhalation of the short lived radon progeny imparts a radiation dose to the lung, to which an increased risk of lung cancer is attributed due to the alpha particle irradiation of the secretory and basal cells of the respiratory tract. The indoor radon concentration is dependent on the texture, porosity, permeability, water content of the soil underlying the structure and the radon behaviour in soils on aspects of geology and climate. The direct cause of high radon entry rates into structures exhibiting high indoor radon concentrations are fractures in bedrock formations, cracks in the soil, and similar inhomogeneities in the materials of the foundation of the structures. Other factors influencing indoor radon concentration includes exhalations from the walls and ceilings, building design and material, cracks and openings in the foundation of the buildings. The geological factors in the study area promote radon accumulation especially in buildings and dwellings. The world average annual effective dose in the indoor environments is 1.01 mSv.y -1 . The importance of radon level measurements in school buildings is of interest as children are more sensitive to radon exposure than adults. Hence, radon measurements in 10 schools have been undertaken in the present study

  18. Seasonal correction factors in radon exposure assessment: are they help or hindrance?

    International Nuclear Information System (INIS)

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

    2008-01-01

    Northern Hemisphere radon levels are generally higher in Winter than in Summer, primarily due to the increased interior/exterior temperature difference during the heating season, which results in greater atmospheric pressure differential and enhanced radon ingress. Following a survey of domestic radon levels in the United Kingdom (UK), the former National Radiological Protection Board (NRPB) established measurement protocols and promulgated nationally-applicable Seasonal Correction Factors (SCF). These factors convert a one-month or three-month radon concentration measurement, commencing in any month of the year, to an annual mean radon concentration. Subsequent study suggests that this approach may not be sufficiently sensitive to local conditions, and a major independent investigation reported seasonal correction factors specific to nine geographic regions, together with a composite set applicable to all regions. Similar geographical variability has been observed in other countries. In a recent evaluation of the applicability of short-term exposures in quantifying long-term domestic radon levels, radon levels in 34 houses were monitored over a 12-month period with 1-week, 1-month and 3-month exposures. Radon concentration variation departed significantly from that expected on the basis of the recommended SCFs, with year-end discontinuities at all exposure durations. Weekly monitoring with electrets was continued in three of these locations for four years. Short-term variations in radon levels were observed, particularly during the shorter exposures, and this dataset has also shown year-on-year variations. Overall, SCFs derived from this dataset are significantly lower than those recommended, but are comparable with other results from the UK and elsewhere, particularly those that recognise geological diversity and are consequently prepared on a regional rather than a national basis. These findings call into question the validity of using nationally

  19. Radiation levels of radon gas and its progeny in labor activities of mine interior and their effects in the Bolivian workers to 4000 m

    International Nuclear Information System (INIS)

    Mamani M, R.; Claros J, J. T.; Vasquez A, R.; Chirveches, H.; Weyer, J.; Arnold, D.

    2014-08-01

    The objectives of this study are guided to determine the radiation charges to those that the mining workers are exposed, in order to assume the appropriate protection measures. The first phase of this study begun in March of 2009, with the support of the Freiberg University (Germany), has been preceded of different scientific events and preparatory measurements in the Universidad Autonoma Tomas Frias (UATF) and Cerro Rico de Potosi. Experimentally the presence of radon gas has been quantified by means of measurements in 7 mines of Cerro Rico de Potosi, the COMSUR mines (today SINCHY WAYRA) and the state mining company COMIBOL (Oruro-Huanuni), using the measurement equipment Alpha Zaeller-2 (AZ-2). The Radon-222 that emerges of the interior of the fractured rocks and/or loose rocks, with more intensity if they are fresh, is inhaled by the mining worker. Considering the breathing parameters (1, 2 m 3 /h), recommended by the ICRP, was observed that the miners breathing of the region is more bigger, due to the high effort that they develop in the work. Therefore, the calculation results of the concentration of the radiation activity of Radon, allow assuming that this is the causing of the damage to the lungs in the human body. Outdoor or in superficial tunnels, the impact is low or imperceptible. But when the process is verified to more depths in an underground mine, or not properly ventilated, the concentration as well as the exposure dose to the radiation of radon gas is increased to amazing values. Assuming that the maximum permissible limit is of 20 mSv, the study has established some values that exceeded this limit in the Bolivian mining, not controlled in this field until now. The component of the medical study, through exams: hematology and spirometric, notes that, by the complex inhalation of: air + powders + Radon gas and others in his working environment, contribute strongly to the generation of lethal illnesses in the mining worker, as the Poliglobulia

  20. Radon concentration levels in Fatima Jinnah women university Pakistan

    International Nuclear Information System (INIS)

    Khan, S.A.; Ali, S.; Tufail, A.; Qureshi, A.A.

    2005-01-01

    Public exposure to radioactive gas radon and its progeny present in the air results in the largest contribution to total effective dose received by human beings. It is therefore of great concern to monitor radon concentration in energy conserved air tight buildings. Measurements of radon in the Fatima Jinnah Women University (FJWU) have been carried out for investigation and comparison of radon concentration in the new and old buildings of the campus at Rawalpindi, Pakistan. The study was done because according to the international guidelines concerning environmental problems, it is necessary to evaluate and know the radon levels, especially since most of the natural radiation dose to human beings comes from radon gas and its progeny. Solid State Nuclear Track Detectors (SSNTDs) being efficient, therefore, the measurements were carried out by passive, time integrated method, using CR-39 detector in polythene bags. The detectors were exposed for more than six month in various locations indoors and outdoors. The detectors were etched using NaOH, the tracks were counted manually, and the track density was converted to radon concentration. Radon concentration varied from 31 to 213 Bq.m -3 in old building and from 27 to 143 Bq.m -3 in new buildings, showing slight elevated values in the old buildings. Radon concentration values were found to be less than the values quoted by radiation protection agencies. Radiation dose due to radon varied in the university campus depending on occupancy factor. (author)

  1. Human disease from radon exposures: the impact of energy conservation in buildings

    International Nuclear Information System (INIS)

    Budnitz, R.J.; Berk, J.V.; Hollowell, C.D.; Nazaroff, W.W.; Nero, A.V.; Rosenfeld, A.H.

    1978-01-01

    The level of radon and its daughters inside conventional buildings is often higher than the ambient background level. Interest in conserving energy is motivating home-owners and builders to reduce the rate of infiltration of fresh air into homes, and hence to increase the concentration of indoor air contaminants, including radon. It is unlikely, but possible, that the present radiation levels from radon daughters account for much of the lung cancer rate in non-smokers. In any event, it is likely that some increased lung cancer risk would result from increased radon exposures; hence, it is desirable not to allow radon concentrations to rise significantly. There are several ways to circumvent the increased risk without compromising energy conservation considerations

  2. Evaluation of radon occurrence in groundwater from 16 geologic units in Pennsylvania, 1986–2015, with application to potential radon exposure from groundwater and indoor air

    Science.gov (United States)

    Gross, Eliza L.

    2017-05-11

    Results from 1,041 groundwater samples collected during 1986‒2015 from 16 geologic units in Pennsylvania, associated with 25 or more groundwater samples with concentrations of radon-222, were evaluated in an effort to identify variations in radon-222 activities or concentrations and to classify potential radon-222 exposure from groundwater and indoor air. Radon-222 is hereafter referred to as “radon.” Radon concentrations in groundwater greater than or equal to the proposed U.S. Environmental Protection Agency (EPA) maximum contaminant level (MCL) for public-water supply systems of 300 picocuries per liter (pCi/L) were present in about 87 percent of the water samples, whereas concentrations greater than or equal to the proposed alternative MCL (AMCL) for public water-supply systems of 4,000 pCi/L were present in 14 percent. The highest radon concentrations were measured in groundwater from the schists, gneisses, and quartzites of the Piedmont Physiographic Province.In this study, conducted by the U.S. Geological Survey in cooperation with the Pennsylvania Department of Health and the Pennsylvania Department of Environmental Protection, groundwater samples were aggregated among 16 geologic units in Pennsylvania to identify units with high median radon concentrations in groundwater. Graphical plots and statistical tests were used to determine variations in radon concentrations in groundwater and indoor air. Median radon concentrations in groundwater samples and median radon concentrations in indoor air samples within the 16 geologic units were classified according to proposed and recommended regulatory limits to explore potential radon exposure from groundwater and indoor air. All of the geologic units, except for the Allegheny (Pa) and Glenshaw (Pcg) Formations in the Appalachian Plateaus Physiographic Province, had median radon concentrations greater than the proposed EPA MCL of 300 pCi/L, and the Peters Creek Schist (Xpc), which is in the Piedmont

  3. Establishing the level of exposure to radon gas in dwellings

    International Nuclear Information System (INIS)

    Karupa, Jackson Uakaningirua

    2016-04-01

    The main source of natural internal irradiation of man is radon and its decay products. In this study, the radon concentration levels in selected dwellings in Erongo region, Swakopmund, Namibia will be estimated using passive or active radon detector. The primary objective of the study is to measure and establish radon levels in selected dwellings in Erongo region, Swakopmund of Namibia. Measurements will be carried out for the period of twelve months and after three months period the detectors will be exchanged for laboratory analysis. The results obtained from the study will reveal the concentration of radon in most of the selected dwellings in Erongo region, Swakopmund, Namibia. Once Radon level is measured or identified, the results with data from work done in other environments in Africa and elsewhere will be compared. In case of high radon concentrations in dwelling, the occupants will be advised to ensure good ventilation practices as cost effective means of mitigation of indoor radon gas level in the area. (au)

  4. Occupational exposure to radon in Australian Tourist Caves an Australian-wide study of radon levels

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, S B; Langroo, R; Peggie, J R [Australian Radiation Laboratory. Yallambie, VIC (Australia); Lyons, R G [University of Auckland, Auckland, (New Zealand). Department of Physics; James, J M [University of Sydney, Sydney, NSW (Australia). Department of Chemisty

    1996-02-01

    The study described in this report sets out to determine which Australian show caves have long- term radon levels in excess of the proposed action level of 1000 Bq m{sup -3}. The collaborative study between the Australian Radiation Laboratory (ARL), the University of Sydney and the University of Auckland, was carried out with the support of a Research Grant from Worksafe Australia. The aims of this study were to measure radon levels for each season over a period of one year, at representative sites in all developed show caves around Australia, to determine yearly average radon levels for each cave tour, based on these site measurements, to estimate the radiation doses to the tour guides employed in these caves, and to identify caves with radon concentrations in excess of the action level. (authors) 7 refs., 10 tabs., 2 figs.

  5. Occupational exposure to radon in Australian Tourist Caves an Australian-wide study of radon levels

    International Nuclear Information System (INIS)

    Solomon, S.B.; Langroo, R.; Peggie, J.R.; Lyons, R.G.; James, J.M.

    1996-02-01

    The study described in this report sets out to determine which Australian show caves have long- term radon levels in excess of the proposed action level of 1000 Bq m -3 . The collaborative study between the Australian Radiation Laboratory (ARL), the University of Sydney and the University of Auckland, was carried out with the support of a Research Grant from Worksafe Australia. The aims of this study were to measure radon levels for each season over a period of one year, at representative sites in all developed show caves around Australia, to determine yearly average radon levels for each cave tour, based on these site measurements, to estimate the radiation doses to the tour guides employed in these caves, and to identify caves with radon concentrations in excess of the action level. (authors)

  6. Development of lesions in Syrian golden hamsters following exposure to radon daughters and uranium ore dust

    International Nuclear Information System (INIS)

    Cross, F.T.; Palmer, R.F.; Busch, R.H.; Filipy, R.E.; Stuart, B.O.

    1981-01-01

    The development of lesions in Syrian Golden hamsters was studied following life-span inhalation exposures to radon, radon daughters and uranium ore dust. Clinical measurements revealed that life-span exposures to radon daughters and uranium ore dust, singly or in combination, caused no significant changes in mortality patterns, body weights or hematological parameters compared with controls. Pulmonary and nonpulmonary lesions are presented. Exposure to uranium ore dust provoked inflammatory and proliferative responses in the lungs consisting of macrophage accumulation, alveolar cell hyperplasia, and adenomatous alteration of alveolar epithelium. The adenomatous lesions did not undergo further morphologic change. Exposure to radon and radon daughters was associated with increased occurrence of bronchiolar epithelial hyperplasia and with metaplastic changes of alveolar epithelium. Squamous carcinoma developed in only a few hamsters and only in those animals receiving radon daughter exposures exceeding 8000 WLM. It is concluded that an animal model other than the hamster would be more appropriate for study of the pulmonary carcinogenic potential of uranium ore alone. (author)

  7. Effects of Radon and UV Exposure on Skin Cancer Mortality in Switzerland

    Science.gov (United States)

    de Hoogh, Kees; Hauri, Dimitri; Vicedo-Cabrera, Ana M.; Schindler, Christian; Huss, Anke; Röösli, Martin

    2017-01-01

    Background: Skin cancer incidence in Switzerland is among the highest in the world. In addition to exposure to ultraviolet (UV) radiation, radon alpha particles attached to aerosols can adhere to the skin and potentially cause carcinogenic effects. Objectives: We investigated the effects of radon and UV exposure on skin cancer mortality. Methods: Cox proportional hazard regression was used to study the association between exposures and skin cancer mortality in adults from the Swiss National Cohort. Modeled radon exposure and erythemal-weighted UV dose were assigned to addresses at baseline. Effect estimates were adjusted for sex, civil status, mother tongue, education, job position, neighborhood socioeconomic position, and UV exposure from outdoor occupation. Results: The study included 5.2 million adults (mean age 48 y) and 2,989 skin cancer deaths, with 1,900 indicating malignant melanoma (MM) as the primary cause of death. Adjusted hazard ratios (HR) for MM at age 60 were 1.16 (95% CI: 1.04, 1.29) per 100Bq/m3 radon and 1.11 (1.01, 1.23) per W/m2 in UV dose. Radon effects decreased with age. Risk of MM death associated with residential UV exposure was higher for individuals engaged in outdoor work with UV exposure (HR 1.94 [1.17, 3.23]), though not statistically significantly different compared to not working outdoors (HR 1.09 [0.99, 1.21], p=0.09). Conclusions: There is considerable variation in radon and UV exposure across Switzerland. Our study suggests both are relevant risk factors for skin cancer mortality. A better understanding of the role of the UV radiation and radon exposure is of high public health relevance. https://doi.org/10.1289/EHP825 PMID:28686556

  8. Environmental assessment of indoor radon gas exposure health hazards and some of its public risks

    International Nuclear Information System (INIS)

    Hussein, Abd El-Razik. Z.; Ibrahim, M.Se.; Ragab, M.H.; El-Bukhari, M.S.

    2005-01-01

    This study examine the relationship between indoor radon gas exposure and the cancer risk and housing characteristics in lung cancer risk houses (CRH) compared to non lung cancer risk houses (NCRH). Mean radon concentrations measured by active method were significantly higher among CRH compared to NCRH, 9:93 pCi/L versus 4.56 pCi/L, respectively. There was no statistically significant diurnal variation as regards radon levels in all examined houses. Indoor radon concentrations show statistically significance in houses with bad ventilation (low air change rate) compared to houses with good ventilation (high air change rate). Houses with floor material of tiles, had statistically significant higher radon concentrations. Neither finishing wall material nor indoor gas source shows statistically significance as regard radon levels. Radon levels > 4 pCi/L (US EPA action level) were statistically significance higher in bed rooms compared levels in living rooms. High radon concentrations were reported in lung cane risk houses and in houses with bad ventilation

  9. Indoor radon distribution in metropolitan region of Belo Horizonte, Brazil

    International Nuclear Information System (INIS)

    Santos, Talita O.; Oliveira, Arno H. de

    2009-01-01

    Human beings are exposed to ionizing radiation from many natural sources. Radon and its progeny have been recognized as the most important contributors to the natural radioactivity dose, accounting for about half of all human exposure to ionizing radiation. Radon ( 222 Rn) is a α-radioactive noble gas derived from the natural series of uranium (2 38 U), which occurs in a wide concentration range in all geological materials, especially, in rocks, soils and waters. By diffusion and convection, radon migrates from the rocks and soils to atmosphere and through fissures, pipes and holes it may enter the dwellings and other buildings. Another important radon source in dwellings is its emanation from the construction material. The radon progeny concentration in dwellings has been receiving considerable global attention due to its potential effect in causing lung cancer if it deposited in upper respiratory tract when inhaled. This paper presents radon concentration distribution in dwellings in Metropolitan Region of Belo Horizonte - RMBH. The effective dose estimate is also presented for the RMBH inhabitants. The geological settings of the area are Archean rocks of Granitic Gnaissic Complex and of metasediments sequences of the great Precambrian unit of the Iron Quadrangle of Minas Gerais, Brazil. Radon concentration measurements were carried out with continuous detector AlphaGUARD PQ200PRO (Genitron), in passive mode and with passive detectors E-PERM R Eletret Ion Chamber-EIC. The radon progeny concentration was carried out with a solid state alpha spectroscope, the DOSEman PRO (Sarad). It was found an indoor radon concentration varying in a large range from 18.5 to 2671.4 Bq/m -3 , with an average value of 148.0 Bqm -3 and geometric mean equal to 128.2 Bqm -3 . The variable results are due mainly to region geological factors and building material composition of dwellings. The equilibrium factor between radon and its progeny were determined in dwellings, as 0.3 in

  10. Outlines of a study of some indicators of exposure of underground workers to radon in Slovakia

    Energy Technology Data Exchange (ETDEWEB)

    Beno, M; Nikodemova, D; Vladar, M; Fueloep, M; Vicanova, M [Inst. of Preventive and Clinical Medicine, Bratislava (Slovakia)

    1996-12-31

    In this paper some indicators of exposure of underground workers to radon in Slovakia which will be used for determination of miners radiation burden and for the radon dose estimate was explained. The projected study has a dose-effect scaffold and its projected goals are on the side of dose assessment: 1) to determine the professional exposure of underground workers to radon by personal dosimetry and to establish a database of integrated personal doses for future epidemiological studies; 2) to introduce the method of counting the radionuclide {sup 210}Pb in the bones and skulls of underground workers. On the side of effect assessment the goals are: 1) to find out if a dependence of the number of chromosomal aberrations (CA) and micronuclei in the lymphocytes from radon dose exists. The measurements of radon in mines, preferentially those by personal dosimeters as well as an existing database of radon concentration measurements in dwellings and caves will serve for the radon dose estimate; 2) to compare the DNA-repair rate in the lymphocytes of people professionally exposed to radon in Slovak caves with the same rate as assessed in unexposed people; 3) to find out the proportional role of confounding factors such as smoking, alcohol abuse, exposure to dust etc., which might influence upon the interpretation of the dose from radon to health response relationship; 4) to establish a central database of lung cancer cases in professionally exposed underground workers for future epidemiological studies. The direct method will rely upon determination of miners radiation burden based on the {sup 210}Pb activity deposited in skeleton. The experimental design to assess the effects will have three main methodological parts: 1) determination of the count of chromosomal aberrations and micronuclei using classical methods; 2) determination of the chromosomal changes using the fluorescent in situ hybridization method; 3) determination of the DNA-repair rate. (J.K.) 8 refs.

  11. Seasonal variation of radon concentration in different rooms of dwellings

    International Nuclear Information System (INIS)

    Jayasheelan, A.; Manjunatha, S.; Chandrashekaraiah, G.; Shankar, P.; Umeshareddy, K.; Ningappa, C.

    2016-01-01

    Indoor air is a dominant exposure for humans, where more than half of the body's intake during a lifetime. The main natural sources of indoor radon are soil, building materials like sand, rocks, cement, marble, bricks, ceramics, natural gas and the underground-derived water supply. In the present research, dwellings with similar building style (similar floorings and dimensions) from Tumkur city were studied for indoor radon, thoron and their progeny measurements for various seasons

  12. Radon dosimetry for workers: ICRP's approach

    International Nuclear Information System (INIS)

    Marsh, James W.; Laurier, Dominique; Tirmarche, Margot

    2017-01-01

    The International Commission on Radiological Protection (ICRP) has recently published two reports on radon exposure; Publication 115 on lung cancer risks from radon and radon progeny and Publication 126 on radiological protection against radon exposure. A specific graded approach for the control of radon in workplaces is recommended where a dose assessment is required in certain situations. In its forthcoming publication on Occupational Intakes of Radionuclides (OIR) document, Part 3, effective dose coefficients for radon and thoron will be provided. These will be calculated using ICRP reference biokinetic and dosimetric models. Sufficient information and dosimetric data will be given so that site-specific dose coefficients can be calculated based on measured aerosol parameter values. However, ICRP will recommend a single dose coefficient of 12 mSv per working level month (WLM) for inhaled radon progeny to be used in most circumstances. This chosen reference value was based on both dosimetry and epidemiological data. In this paper, the application and use of dose coefficients for workplaces are discussed including the reasons for the choice of the reference value. Preliminary results of dose calculations for indoor workplaces and mines are presented. The paper also briefly describes the general approach for the management of radon exposure in workplaces based both on ICRP recommendations and the European directive (2013/59/EURATOM). (authors)

  13. LIFETIME LUNG CANCER RISKS ASSOCIATED WITH INDOOR RADON EXPOSURE BASED ON VARIOUS RADON RISK MODELS FOR CANADIAN POPULATION.

    Science.gov (United States)

    Chen, Jing

    2017-04-01

    This study calculates and compares the lifetime lung cancer risks associated with indoor radon exposure based on well-known risk models in the literature; two risk models are from joint studies among miners and the other three models were developed from pooling studies on residential radon exposure from China, Europe and North America respectively. The aim of this article is to make clear that the various models are mathematical descriptions of epidemiologically observed real risks in different environmental settings. The risk from exposure to indoor radon is real and it is normal that variations could exist among different risk models even when they were applied to the same dataset. The results show that lifetime risk estimates vary significantly between the various risk models considered here: the model based on the European residential data provides the lowest risk estimates, while models based on the European miners and Chinese residential pooling with complete dosimetry give the highest values. The lifetime risk estimates based on the EPA/BEIR-VI model lie within this range and agree reasonably well with the averages of risk estimates from the five risk models considered in this study. © Crown copyright 2016.

  14. Radon in uranium mining industry and application of SSNTD in monitoring and dose evaluation

    International Nuclear Information System (INIS)

    Khan, A.H.

    2006-01-01

    Radon is present everywhere and accounts for a globally major share of natural radiation exposure of the population. Though it is present in most of the underground workings it is a source of concern in uranium mining and ore processing industry as well as in many other operations carried out in confined spaces below the ground, like railway tunnels and non-uranium underground mines. Many monitoring techniques are available for evaluation of radon and its short-lived progeny concentrations. Scintillation cell techniques, also called Lucas cell, is one of the earliest developed methods of radon monitoring still widely used in mines where appreciable concentrations of radon above about 40-50 Bq.m -3 are expected. For low concentration of radon as observed in the atmosphere, dwellings and other workplaces, the radon absorption in charcoal followed by gamma counting, two filter method and electrostatic techniques are available. Solid state nuclear track detectors (SSNTD) are now widely used for a variety of situations for monitoring of low level of radon over an extended period of time. It is now extensively used in radon monitoring in dwellings and also in radon dosimetry in mines. Radon daughters being the more important contributors to the internal radiation exposure are also being monitored using conventional techniques as well as SSNTD. Various monitoring techniques for radon and its progeny and the concentrations observed at different stages of uranium mining, ore processing and tailings management are discussed in this presentation. (author)

  15. Residential Radon Exposure and Skin Cancer Incidence in a Prospective Danish Cohort

    DEFF Research Database (Denmark)

    Brauner, Elvira Vaclavik; Loft, Steffen; Sørensen, Mette

    2015-01-01

    Background Although exposure to UV radiation is the major risk factor for skin cancer, theoretical models suggest that radon exposure can contribute to risk, and this is supported by ecological studies. We sought to confirm or refute an association between long-term exposure to residential radon...... and the risk for malignant melanoma (MM) and non-melanoma skin cancer (NMSC) using a prospective cohort design and long-term residential radon exposure. Methods During 1993-1997, we recruited 57,053 Danish persons and collected baseline information. We traced and geocoded all residential addresses...... exposure may contribute to development of basal cell carcinoma of the skin. We cannot exclude confounding from sunlight and cannot conclude on causality, as the relationship was stronger amongst persons living in apartments and nonexistent amongst those living in single detached homes....

  16. Assessing exposure to radon in the United States: An EPA [Environmental Protection Agency] perspective

    International Nuclear Information System (INIS)

    Guimond, R.J.; Magno, P.J.

    1990-01-01

    A number of investigators have suggested that exposure to radon decay products may be a significant factor associated with the incidence of some lung cancers in the US. Various scientists have estimated that 5,000 to greater than 20,000 lung cancers per year may be attributable to radon if the average level in the US is 0.004 working levels (WL). To help assess the significance of exposure to radon across the US and within specific geographical regions, more information is needed. The paper describes efforts in the Environmental Protection Agency to assess this problem and determine the most appropriate means for dealing with risks posed by radon in new and existing housing

  17. Calculation of lung cancer incidence in the Netherlands by smoking and radon exposure. Implications for the effect of radon; Berekening van de longkankerincidentie in Nederland door roken en blootstelling aan radon. Implicaties voor het effect van radon

    Energy Technology Data Exchange (ETDEWEB)

    Leenhouts, H.P.; Brugmans, J.P. [Laboratorium voor Stralingsonderzoek, Rijksinstituut voor Volksgezondheid en Milieu RIVM, Bilthoven (Netherlands)

    2001-09-01

    Although the main cause of lung cancer is smoking cigarettes, part of the cases are subscribed to radon exposure, in particular {alpha}-radiation from daughter products. However, the relation between lung cancer and radon exposure is rather insecure. Based on international reports (e.g. BEIR VI) and extrapolation of lung cancer incidence in uranium mine workers to the population of the USA and subsequently to the Netherlands, the number of lung cancer cases in the Netherlands is estimated to be circa 800 per year, varying between 200-2000. Results of the analysis are summarized in this article. 10 refs.

  18. Level of radon and its daughters, and internal exposure doses in Shaanxi province

    International Nuclear Information System (INIS)

    Fan Xin; Zhang Yawei; Yu Huilian

    1992-01-01

    About 4500 indoor and outdoor air samples were collected with FDT-84 sampler throughout Shaanxi Province in various seasons, and the concentrations of radon and its daughters in the air were determined with FD-3016 scintillator. Meanwhile, the diurnal, seasonal and altitudinal variation of radon and its progeny in Xi'an area were observed. The annual effective dose equivalent for individual adult resident was estimated to be 1.73 mSv·a -1 and the annual collective effective dose equivalent for the residents- in the whole province was estimated to be 5.09 ± 10 4 man.Sv·a -1 . The concentration levels and the doses are within the range of the data published in UNSCEAR reports in recent years, and all of them are in the normal range of the natural background

  19. Current status of programmes to measure and reduce radon exposure in Irish workplaces

    International Nuclear Information System (INIS)

    Colgan, P A; Madden, J S; Synnott, H; Fennell, S; Pollard, D; Fenton, D

    2004-01-01

    National legislation, which implements European Council Directive 96/29/EURATOM in Ireland, sets a reference level of 400 Bq m -3 averaged over any 3 month period for radon exposure in the workplace and also empowers the Radiological Protection Institute of Ireland to direct employers to have radon measurements carried out. This legislation came into effect in May 2000. Radon measurements have already been completed in show caves and other underground workplaces. Between 1998 and 2001, over 33 800 individual radon measurements were carried out in all ground floor offices and classrooms in 3444 schools nationwide as part of a programme undertaken jointly with the Department of Education and Science. Where the average indoor radon concentration in one or more rooms exceeded 200 Bq m -3 , remedial measures were implemented. For concentrations up to 400 Bq m -3 this involved increased ventilation while for higher concentrations an active sump was normally installed. The results of the survey, as well as the effectiveness of the different remedial strategies, are discussed. In the case of other above ground workplaces, different approaches have been adopted. As a first step, workplaces in two known high radon areas were directed to have radon measurements carried out. This programme had limited success because of problems in obtaining accurate workplace databases and a general lack of awareness on the part of employers of the issues involved. From a sample of 2610 employers directed to measure radon, only 408 actually completed measurements and 37 workplaces were identified as having average 3 month average radon concentrations above 400 Bq m -3 . A total of 1356 employers ignored all correspondence, some of which was sent by registered post and signed for on receipt. Current initiatives are focused on the provision of information and include newspaper advertising as well as publications aimed specifically at both employer and employee representative groups. The ability

  20. Measure of exposure of short-lived radon products using an alpha spectrometer for measuring indoor aerosol activity concentration and dose evaluation; Misure di esposizione ai prodotti di decadimento del radon a breve vita tramite uno spettrometro alfa per la misura dell'attivita' del particolato atmosferico indoor e valutazioni dosimetriche

    Energy Technology Data Exchange (ETDEWEB)

    Berico, M.; Castellani, C.M.; Formignani, M. [ENEA, Divisione Protezione dell' Uomo e degli Ecosistemi, Centro Ricerche Ezio Clementel, Bologna (Italy); Mariotti, F. [Bologna Univ., Bologna (Italy). Dipt. di Fisica

    2001-07-01

    A new italian law introduces the regulation of occupational exposure to radon. To evaluate the inhalation of radon daughters by the workers a sampling device has been assembled with the aim of evaluation of unattached and aerosol attached radon daughters' fractions. The instrument, based on selection of the aerosuspended particles by means of a wire screen type battery and subsequent collection on a total filter, allows to describe the behaviour of both fractions using defined temporal pattern of collecting particles and counting them by alpha spectroscopy. A measurement campaign to test the radon daughter dichotomous spectrometer in comparison with a commercial Radon Working Level meter, has been performed in a research laboratory of central Italy affected by high radon concentrations. The radon concentration during the measurement campaign has been also measured. The equilibrium factor F{sub e}q ad the attachment factor fp have been evaluated during 3 days campaign. Using the measured mean parameters (radon concentration, F{sub e}q, f{sub p}) the dose evaluation for workers using dosimetric approach has been performed. A comparison between the epidemiologic approach, based on the radon concentration, and dosimetric approach is also presented. [Italian] L'esposizione a radon in ambiente lavorativo e la conseguente inalazione dei suoi prodotti di decadimento in forma particolata e' oggetto di una recente normativa italiana in materia di protezione dalle radiazioni ionizzanti. Per rispondere a questa necessita', presso l'Istituto per la Radioprotezione dell'ENEA di Bologna e' stato progettato e realizzato uno spettrometro alfa per la misura della progenie del radon con la finalita' di valutare, su brevi periodi di tempo, la concentrazione individuale dei suoi prodotti di decadimento e, con l'impiego di batterie a diffusione a reti, consentire inoltre la discriminazione della concentrazione della frazione attaccata e non

  1. An assessment of indoor radon exposure in Ireland

    International Nuclear Information System (INIS)

    McLaughlin, J.P.

    1987-01-01

    The results of measurements of indoor radon in over 700 dwellings chosen at ''random'' throughout the Republic of Ireland are presented. The median value of radon in these dwellings was found to be 37 Bq/m 3 (1 pCi/1). The distribution of indoor radon concentration appears to be approximately log-normal with about 2% of the dwellings surveyed having concentrations greater than 400 Bq/m 3 . High radon values were generally found to be more common in western and southern regions of the country than in the more densely populated eastern seabord. Using dose conversion factors in keeping with recent developments in lung dosimetry the median effective dose equivalent to occupants arising from the inhalation of radon daughters in the dwellings surveyed is estimated to be about 1.8 mSv per year. On the same basis for dwellings with indoor radon above 400 Bq/m 3 the continuous effective dose equivalent is estimated to be in excess of 20 mSv per year

  2. Simulation model of lung cancer incidence related to smoking and radon daughter exposure

    International Nuclear Information System (INIS)

    Stolowijk, J.A.J.

    1990-01-01

    A mathematical model of lung cancer and radon daughter exposure is presented. It is aimed to provide a quantitative estimate in the form of dose-effect relationship. The nature of the cigarette smoking and radon exposure interaction it is shown to be a multiplicative or sub-multiplicative function rather than a simpler model in which the effect of the two exposures would be summed. The model was written in the SAS programming language. An annotated listing of the program is given. 4 refs

  3. Radon exposure at a radioactive waste storage facility.

    Science.gov (United States)

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

    2014-06-01

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

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

    Science.gov (United States)

    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.

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

    International Nuclear Information System (INIS)

    Mudd, Gavin M.

    2008-01-01

    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

  6. Correlation of 210Po implanted in glass with radon gas exposure: sensitivity analysis of critical parameters using a Monte-Carlo approach.

    Science.gov (United States)

    Walsh, C; McLaughlin, J P

    2001-05-14

    In recent years, 210Po implanted in glass artefacts has been used as an indicator of the mean radon gas concentration in dwellings in the past. Glass artefacts have been selected in many dwellings and the alpha-recoil implanted 210Po concentration has been measured using various techniques. Some of these retrospective techniques use a model to estimate the retrospective radon gas on the basis of this surface 210Po activity. The accumulation of 210Po on glass surfaces is determined by the deposition regime over the exposure period. The 210Po activity is determined not only by the radon progeny deposition velocities, but by other room parameters such as ventilation rate, aerosol conditions and the surface to volume ratio of the room. Up to now in using room models, a nominal or 'base-case' scenario is used, i.e. a single value is chosen for each input parameter. In this paper a Monte-Carlo analysis is presented in which a probability distribution for each parameter is chosen, based on measurements quoted in the literature. A 210Po surface activity is calculated using a single value drawn from each of the parameter distributions using a pseudo-random number generator. This process is repeated n times (up to 20,000), producing n independent scenarios with corresponding 210Po values. This process permits a sensitivity analysis to be carried out to see the effect of changes in inputs on the model output.

  7. Radon exposure in abandoned metalliferous mines of South America

    International Nuclear Information System (INIS)

    Silva, A.A.R. da; Umisedo, N.; Yoshimura, E.M.; Anjos, R.M.; Valladares, D.L.; Velasco, H.; Rizzotto, M.

    2011-01-01

    Since the days of the Spanish and Portuguese conquerors, South America has been closely associated with the metalliferous ore mining. Gold, silver, tin, lead, tungsten, nickel, copper, and palladium ores have been explored over the last centuries. In addition, there has also been the development and promotion of other economic activities related to mining, as the underground mine tourism. A few works have been published on radon levels in the South American mining. In this study, we investigated the radon transport process and its health hazard in two exhausted and abandoned mines in San Luis Province, Argentina. These mines were chosen because they have different physical configurations in their cavities, features which can affect the air flow patterns and radon concentrations. La Carolina gold mine (32 deg 48' 0'' S, 66 deg 60' 0'' W) is currently a blind end system, corresponding to a horizontal excavation into the side of a mountain, with only a main adit. Los Condores wolfram mine (32 deg 33' 25'' S, 65 deg 15' 20'' W) is also a horizontal excavation into the side of a mountain, but has a vertical output (a shaft) at the end of the main gallery. Three different experimental methodologies were used. Radon concentration measurements were performed by CR-39 nuclear track detectors. The distribution of natural radionuclide activities ( 40 K, 232 Th and 238 U) was determined from rock samples collected along their main adits, using in laboratory gamma-ray spectrometry. The external gamma dose rate was evaluated using thermoluminescent dosimeters and a portable survey meter. The values for the 222 Rn concentration ranged from 0.43 ± 0.04 to 1.48 ± 0.12 kBq/m 3 in the Los Condores wolfram mine and from 1.8 ± 0.1 to 6.0±0.5 kBq/m 3 in the La Carolina gold mine, indicating that, in this mine, the radon levels exceed up to four times the action level of 1.5 kBq/m 3 recommended by the ICRP. The patterns of the radon transport process revealed that the La Carolina

  8. Diseases of uranium miners and other underground miners exposed to radon

    International Nuclear Information System (INIS)

    Samet, J.M.

    1991-01-01

    Excess lung cancer has been demonstrated in many groups of underground miners exposed to radon, including uranium miners and those mining other substances in radon-contaminated mines. In the United States, most underground uranium mines had shut down by the late 1980s, but occupational exposure to radon progeny remains a concern for many other types of underground miners and other underground workers. Worldwide, uranium mining continues, with documented production in Canada, South Africa and other African countries, and Australia. Thus, radon in underground mines remains a significant occupational hazard as the end of the twentieth century approaches.39 references

  9. The theoretical risk of non-melanoma skin cancer from environmental radon exposure

    International Nuclear Information System (INIS)

    Eatough, J.P.; Henshaw, D.L.

    1995-01-01

    The skin cancer risk theoretically attributable to radon associated alpha particle radiation is calculated on the basis of recent dosimetry, and published radiation risk factors. The results suggest that of the order of 2% (range 1%-10%) of non-melanoma skin cancers in the UK may be associated with radon exposure at the average UK radon concentration of 20 Bq m -3 . The range quoted is due solely to uncertainties in the estimate of the radon dose to the basal layer of the skin, and additional sources of uncertainty are discussed. The estimate is dependent on the assumption that the target cells for radiation induced skin cancer lie in the basal layer of the epidermis, and that irradiation of the dermis is not necessary for skin cancer induction. Due to the effect of ultraviolet radiation on the risk factors for ionising radiation, ultraviolet radiation exposure must also be involved in the induction of the majority of any skin cancer cases linked to radon exposure. (author)

  10. Rapid determination of radon daughter concentrations

    International Nuclear Information System (INIS)

    Bigu, J.

    1990-08-01

    A technical evaluation of four radon 222 progeny measuring instruments has been conducted. The evaluation has been carried out under laboratory controlled conditions and at several locations in an underground uranium mine. The laboratory evaluation consisted of a thorough study of the behaviour and performance of the instruments under a wide variety of environmental conditions such as radon 222 gas concentration, radon 222 progeny concentration, temperature, relative humidity, aerosol concentration, and gamma-field exposure. The four instruments tested were: the Pylon WL-1000C, the MDA IWLM-811, the MIMIL IIM, and the EDA WLM-30. The readings of the instruments were compared with a widely accepted radon 222 progeny concentration measuring method, namely, the Thomas-Tsivoglou method. Two variables affected two instruments significantly, namely, under high aerosol concentration conditions, one of the instruments (EDA WLM-30) ceased to operate because of filter loading. The other variable was gamma-field exposure which affected another instrument (MDA-811) adversely. The instruments were rated according to several criteria. The overall best performer was the MIMIL IIM, although other instruments also fared quite well under a variety of experimental conditions

  11. Radon in Africa: South African Lessons Learnt

    International Nuclear Information System (INIS)

    Simanga, A.T.

    2010-01-01

    Radon remained a chemical curiosity for decades, promoted at some stage as a health giving gas. Mining related history: (based on ICRP 65) dating back to 15 Century when high mortality from lung cancer was observed among miners in Schneeberg. After the Curies had extracted Radium from Jachymov ores (1898), radon was identified. When measurements were done in Schneeberger and Jachymov mines high concentrations of radon were found. Initially a link was assumed between lung cancer and high radon concentration based on the measurements. (The assumption was not generally accepted).In 1953 William F. Bale indicated that the causative agents of lung cancer was the radon progeny and not radon gas. A possible lung cancer risk to members of the public was discovered very recently (first published results were based on the indoor measurements done in Sweden in a study initiated by Rolf Sievert) Much attention has been given to radon as a radiological health hazard: Recently human exposure to radon progeny in buildings has emerged as an important issue. Lung cancer is the principal concern associated with Rn exposure. The principal concern is associated with radon progeny. These species are chemically reactive, and may be deposited on respiratory tract tissues when inhaled. Subsequent alpha particle decay may damage cells near the deposition site, contributing to increased risk of lung cancer Radon: In Occupational Exposure Protection against Rn Exposure is a Techno-Legal Legal Aspects: There has to be a national legislative framework for the protection of workers against radon The legal framework should entail, inter alia: - Set up of regulator, development of regulations and standards to enable compliance assurance and other protection issues, training of technical people. 10 Legislative Framework in South Africa National Nuclear Regulatory Act (1999) Enables the regulator (NNR) to exercise oversight for Rn protection Occupational Exposure is mainly in Mining and Mineral

  12. Radiation levels of radon gas and its progeny in labor activities of mine interior and their effects in the Bolivian workers to 4000 m; Niveles de radiacion de gas radon y su progenie en actividades laborales de interior mina y sus efectos en los trabajadores bolivianos a 4000 m

    Energy Technology Data Exchange (ETDEWEB)

    Mamani M, R.; Claros J, J. T.; Vasquez A, R.; Chirveches, H. [Universidad Autonoma Tomas Frias, Villa Imperial de Potosi (Bolivia, Plurinational State of); Weyer, J.; Arnold, D., E-mail: raulm2k13@hotmail.com [Universidad Tecnica de Freiberg, Academia de Minas, Akademiestrabe 6, 09599 Freiberg (Georgia)

    2014-08-15

    The objectives of this study are guided to determine the radiation charges to those that the mining workers are exposed, in order to assume the appropriate protection measures. The first phase of this study begun in March of 2009, with the support of the Freiberg University (Germany), has been preceded of different scientific events and preparatory measurements in the Universidad Autonoma Tomas Frias (UATF) and Cerro Rico de Potosi. Experimentally the presence of radon gas has been quantified by means of measurements in 7 mines of Cerro Rico de Potosi, the COMSUR mines (today SINCHY WAYRA) and the state mining company COMIBOL (Oruro-Huanuni), using the measurement equipment Alpha Zaeller-2 (AZ-2). The Radon-222 that emerges of the interior of the fractured rocks and/or loose rocks, with more intensity if they are fresh, is inhaled by the mining worker. Considering the breathing parameters (1, 2 m{sup 3}/h), recommended by the ICRP, was observed that the miners breathing of the region is more bigger, due to the high effort that they develop in the work. Therefore, the calculation results of the concentration of the radiation activity of Radon, allow assuming that this is the causing of the damage to the lungs in the human body. Outdoor or in superficial tunnels, the impact is low or imperceptible. But when the process is verified to more depths in an underground mine, or not properly ventilated, the concentration as well as the exposure dose to the radiation of radon gas is increased to amazing values. Assuming that the maximum permissible limit is of 20 mSv, the study has established some values that exceeded this limit in the Bolivian mining, not controlled in this field until now. The component of the medical study, through exams: hematology and spirometric, notes that, by the complex inhalation of: air + powders + Radon gas and others in his working environment, contribute strongly to the generation of lethal illnesses in the mining worker, as the Poliglobulia

  13. Indoor radon survey in Eastern Sicily

    International Nuclear Information System (INIS)

    Catalano, R.; Immè, G.; Mangano, G.; Morelli, D.; Tazzer, A. Rosselli

    2012-01-01

    Inhalation of radon (Rn-222) and its progeny is one of the most significant sources of natural radiation exposure of the population. Nowadays, high radon exposures have been shown to cause lung cancer and many governments all over the world have therefore recommended that radon exposures in dwellings and indoor workplaces should be limited. Radon levels in buildings vary widely from area to area depending on local geology. This paper presents the results of a long-term survey of radon concentrations carried out from 2005 till 2010 in schools and dwellings of Eastern Sicily, using the solid-state nuclear track detector (SSNTD) technique. The investigated area shows medium-high indoor radon concentrations, higher than the Italian average of about 70 Bq/m 3 , with peaks of 500 Bq/m 3 or more in buildings near active faults. Fortunately, only a small fraction of the measurements, about 1.5% of total, was found greater than EU and Italian action limits for indoor and workplaces. - Highlights: ► In this paper we report radon monitoring survey carried out in the east Sicily in schools and dwellings. ► The detection methodology was the solid-state nuclear track detector one. ► The work was supported by a national projects financed by the National Institute of Nuclear Physics.

  14. Lung cancer attributable to indoor radon exposure in France using different risk models

    International Nuclear Information System (INIS)

    Catelinois, O.C.; Laurier, D.L.; Rogel, A.R.; Billon, S.B.; Tirmarche, M.T.; Hemon, Dh.; Verger, P.V.

    2006-01-01

    Full text of publication follows: Radon exposure is omnipresent for the general public, but at variable levels, because radon mainly comes from granitic and volcanic subs oils as well as from certain construction materials. Inhalation of radon is the main source of exposure to radioactivity in the general population of most countries. In 1988, the International Agency for Research on Cancer declared radon to be carcinogenic for humans (lung cancer): radon is classed in the group 1. The exposure of the overall general population to a carcinogenic component led scientists to assess the lung cancer risk associated to indoor radon. The aim of this work is to provide the first lung cancer risk assessment associated with indoor radon exposure in France, using all available epidemiological results and performing an uncertainty analysis. The number of lung cancer deaths potentially associated with radon in houses is estimated for the year 1999 according to several dose-response relationships which come from either cohorts of miners or joint analysis of residential case-controls studies. The variability of indoor radon exposure in France and uncertainties related to each of the dose-response relationships are considered. The assessment of lung cancer risk associated with domestic radon exposure considers 10 dose-response relationships resulting from miners cohorts and case-control studies in the general population. A critical review of available data on smoking habits has been performed and allowed to consider the interaction between radon and tobacco. The exposure data come from measurements campaigns carried out since the beginning of the 1980's by the Institute for Radiation protection and Nuclear Safety and the Health General Directory in France. The French lung cancer mortality data are provided by the INSERM. Estimates of the number of attributable cancers are carried out for the whole country, stratified by 8 large regions and b y 96 departments for the year 1999

  15. Indoor exposure to radon and its health effects

    International Nuclear Information System (INIS)

    Loskiewicz, J.

    1997-10-01

    Radon (Rn-222) is a noble radioactive gas which originates during U-238 series decay. As a noble gas it is not reacting with soils and building materials and therefore is showing large mobility due to its half-life of 3.82 days. It decays through alpha emission and is producing other radioactive isotopes (Po-218, Bi-214 etc.) which are solid. The migration of radon and its decay products can be in unattached form or attached to aerosols. The size of aerosol particles is important for adhesion coefficient value and for inhalation probability by human respiratory system. The unattached radon is penetrating more easily into lung space and there it may decay into radioactive and alpha emitting solid isotopes. The emitted alpha particle can damage sensitive cells. An alpha particle that penetrates that epithelial cells can deposit enough energy in a cell to kill or transform it. The transformed cell, alone or through interaction with some other agent, has the potential to develop eventually into a lung cancer. The data on risk of a lung cancer occurrence for high and medium concentrations of radon in the air will also be presented. (author)

  16. Propositions for the implementation and reinforcement of surveillance activities of exposure and risks associated to radon inhalation

    International Nuclear Information System (INIS)

    2003-10-01

    This report treats exclusively of exposure by inhalation. It expresses the propositions relative to the implantation and the development of an information network allowing to characterize the radon exposures by inhalation and associated risks. (N.C.)

  17. Radon Measurements in Egypt using passive etched track detectors. A Review

    Energy Technology Data Exchange (ETDEWEB)

    Gomaa, M A [National Network of Radiation Physics. Atomic Energy Authority (Egypt); Hussein, A S [Radiation Protection Department, Nuclear Power Plants Authority, (Egypt); El-Arabi, A M [Physics Department, Faculty of Science, South Valley University, Qena, (Egypt)

    2005-04-01

    Radon and its progeny may cause serious radiation harm to human health such as lung cancer and other types. Radon measurements based on alpha particles etched track detectors (LR-115, CR-39) are very attractive for assessment of radon exposure. This is due to their high sensitivity, low cost, easy to handle and retain a permanent record of data. Also these detectors can incorporate the effects of seasonal and diurnal fluctuation of radon activity concentrations due to physical, geological and meteorological factors. The present review is based mainly on the topic of passive etched track detectors for the measurements of radon in Egypt in the recent years. Published papers includes the measurements of radon in dwellings, working places, Cairo Metro stations, ancient Pharaonic places and uranium exploration galleries as well as assessment of radon in drinking water.

  18. Measurement of concentration and size distribution of radon decay products in homes using air cleaners

    International Nuclear Information System (INIS)

    Montassier, N.; Hopke, P.K.; Shi, Y.; McCallum, B.

    1992-01-01

    By removing particles, air cleaners can also eliminate radon decay products. However, by removing the particles, the open-quotes unattachedclose quotes fraction of the radon progeny is increased leading to a higher dose per unit exposure. Thus, both the concentration and size distributions of the radon decay products are needed to evaluate air cleaners. Three types of room air cleaners, NO-RAD Radon Removal System, Electronic Air Cleaner and PUREFLOW Air Treatment System were tested in a single family home in Arnprior, Ontario (Canada). Semi-continuous measurements of radon gas concentration and radon decay product activity weighted size distribution were performed in the kitchen/dining room under real living conditions. The effects of air cleaners on both the concentration and size distribution of the radon decay products were measured, and their impact on the dose of radiation given to the lung tissue were examined

  19. Radon Measurements in Egypt using passive etched track detectors. A Review

    International Nuclear Information System (INIS)

    Gomaa, M.A.; Hussein, A.S.; El-Arabi, A.M.

    2005-01-01

    Radon and its progeny may cause serious radiation harm to human health such as lung cancer and other types. Radon measurements based on alpha particles etched track detectors (LR-115, CR-39) are very attractive for assessment of radon exposure. This is due to their high sensitivity, low cost, easy to handle and retain a permanent record of data. Also these detectors can incorporate the effects of seasonal and diurnal fluctuation of radon activity concentrations due to physical, geological and meteorological factors. The present review is based mainly on the topic of passive etched track detectors for the measurements of radon in Egypt in the recent years. Published papers includes the measurements of radon in dwellings, working places, Cairo Metro stations, ancient Pharaonic places and uranium exploration galleries as well as assessment of radon in drinking water

  20. Radon level and radon effective dose rate determination in Moroccan dwellings using SSNTDs

    International Nuclear Information System (INIS)

    Oufni, L.; Misdaq, M.A.; Amrane, M.

    2005-01-01

    Inhalation of radon ( 222 Rn) and its daughter product are a major source of natural radiation exposure. The measurement of radon activity in dwelling is assuming ever increasing importance. It is known from recent surveys in many countries that radon and its progeny contribute significantly to total inhalation dose and it is fairly established that radon when inhaled in large quantity causes lung disorder. Keeping this in view, the indoor radon activity level and radon effective dose rate were carried out in the dwellings of Beni-Mellal, Khouribgra and Ben Guerir cities, Morocco, using the solid state nuclear track detectors (SSNTD) technique. Assuming an indoor occupancy factor of 0.8 and 0.4 for the equilibrium factor of radon indoors, we found that the 222 Rn effective dose rate in the studied dwellings ranges from 1.01 to 7.90mSvy -1 . The radon activity in the corresponding dwellings was found to vary from 40 to 532Bqm -3 . The radon activity has not only been found to vary with seasonal changes, but also with the age, the construction mode of houses, the ventilation conditions and with specific sites and geological materials

  1. Prediction of the variation in risks from exposure to radon at home or at work

    International Nuclear Information System (INIS)

    Chambers, D. B.; Stager, R. H.

    2011-01-01

    On the basis of a review of recent epidemiology, the ICRP recently issued a statement outlining a new approach to radon. The ICRP indicates that the Publication 65 dose conversion convention will be replaced using the dosimetric approach currently used for other radionuclides. Moreover, the ICRP indicates that the dose conversion factor is expected to increase by about a factor of 2. This paper independently examines the risks associated with exposure to radon and decay products through estimation of lifetime excess absolute risks per WLM for a variety of epidemiological risk projection models and baseline cancer and mortality rates. This paper suggests that current ICRP dosimetric models do not reflect the effect of smoking and suggest that basic risk estimates and dose conversion factors be based on risks to non-smoking populations with recognition that lifestyle choices, especially smoking, have a large effect on the risk from exposure to radon. (authors)

  2. Quantitative aspects of radon daughter exposure and lung cancer in underground miners

    International Nuclear Information System (INIS)

    Edling, C.; Axelson, O.

    1983-01-01

    Epidemiological studies have shown an excessive incidence of lung cancer in miners with exposure to radon daughters. The various risk estimates have ranged from six to 47 excess cases per 10 6 person years and working level month, but the effect of smoking has not been fully evaluated. A group of iron ore miners was studied in an attempt to obtain quantitative information about the risk of lung cancer due to radon and its daughters among smoking and non-smoking miners. The results show a considerable risk for miners to develop lung cancer; even non-smoking miners seem to be at a rather high risk. An additive effect of smoking and exposure to radon daughters is indicated and an estimate of about 30-40 excess cases per 10 6 person years and working level month seems to apply on a life time basis to both smoking and non-smoking miners aged over 50. (author)

  3. Radon risks in animals with reference to man

    International Nuclear Information System (INIS)

    Gilbert, E.S.; Cross, F.T.

    1988-10-01

    Radon inhalation studies in animals provide important supplementary information to human data. Because the measurement of exposure characteristics in experimental studies is more accurate than in epidemiological studies, animal studies may provide a more reliable assessment of the dependence of risks on radon-daughter cumulative exposure. Experimental data have also provided information on the dependence of risks on radon-progeny exposure rate, unattached fraction, and disequilibrium, as well as on concomitant exposures to cigarette smoke. A summary of radon studies in animals has been published. Two examples of results from these studies are included; in both cases, results were based on the percent of animals with lung tumors. 8 refs., 4 figs., 3 tabs

  4. Mechanisms of radon injury

    International Nuclear Information System (INIS)

    Cross, F.T.

    1988-01-01

    In this new project, they conduct molecular, cellular and whole-animal research relevant to understanding the inhalation toxicology of radon and radon-daughter exposures. The work specifically addresses the exposure-rate effect in radon-daughter carcinogenesis; the induction-promotion relationships associated with exposure to radon and cigarette-smoke mixtures; the role of oncogenes in radon-induced cancers; the effects of radon on DNA as well as on DNA repair processes; and the involvement of growth factors and their receptors in radon-induced carcinogenesis. Preliminary experiments showed that oncogenes are activated in radon-induced lung tumors. They have therefore begun further exposures pertinent to the oncogene and growth-factor studies. An in vitro radon cellular-exposure system was designed, and cell exposures were initiated. Initiation-promotion-initiation studies with radon and cigarette-smoke mixtures have also begun; and they are compiling a radon health-effects bibliography

  5. The conversion of exposures due to radon into the effective dose: the epidemiological approach

    Energy Technology Data Exchange (ETDEWEB)

    Beck, T.R. [Federal Office for Radiation Protection, Berlin (Germany)

    2017-11-15

    The risks and dose conversion coefficients for residential and occupational exposures due to radon were determined with applying the epidemiological risk models to ICRP representative populations. The dose conversion coefficient for residential radon was estimated with a value of 1.6 mSv year{sup -1} per 100 Bq m{sup -3} (3.6 mSv per WLM), which is significantly lower than the corresponding value derived from the biokinetic and dosimetric models. The dose conversion coefficient for occupational exposures with applying the risk models for miners was estimated with a value of 14 mSv per WLM, which is in good accordance with the results of the dosimetric models. To resolve the discrepancy regarding residential radon, the ICRP approaches for the determination of risks and doses were reviewed. It could be shown that ICRP overestimates the risk for lung cancer caused by residential radon. This can be attributed to a wrong population weighting of the radon-induced risks in its epidemiological approach. With the approach in this work, the average risks for lung cancer were determined, taking into account the age-specific risk contributions of all individuals in the population. As a result, a lower risk coefficient for residential radon was obtained. The results from the ICRP biokinetic and dosimetric models for both, the occupationally exposed working age population and the whole population exposed to residential radon, can be brought in better accordance with the corresponding results of the epidemiological approach, if the respective relative radiation detriments and a radiation-weighting factor for alpha particles of about ten are used. (orig.)

  6. The conversion of exposures due to radon into the effective dose: the epidemiological approach

    International Nuclear Information System (INIS)

    Beck, T.R.

    2017-01-01

    The risks and dose conversion coefficients for residential and occupational exposures due to radon were determined with applying the epidemiological risk models to ICRP representative populations. The dose conversion coefficient for residential radon was estimated with a value of 1.6 mSv year -1 per 100 Bq m -3 (3.6 mSv per WLM), which is significantly lower than the corresponding value derived from the biokinetic and dosimetric models. The dose conversion coefficient for occupational exposures with applying the risk models for miners was estimated with a value of 14 mSv per WLM, which is in good accordance with the results of the dosimetric models. To resolve the discrepancy regarding residential radon, the ICRP approaches for the determination of risks and doses were reviewed. It could be shown that ICRP overestimates the risk for lung cancer caused by residential radon. This can be attributed to a wrong population weighting of the radon-induced risks in its epidemiological approach. With the approach in this work, the average risks for lung cancer were determined, taking into account the age-specific risk contributions of all individuals in the population. As a result, a lower risk coefficient for residential radon was obtained. The results from the ICRP biokinetic and dosimetric models for both, the occupationally exposed working age population and the whole population exposed to residential radon, can be brought in better accordance with the corresponding results of the epidemiological approach, if the respective relative radiation detriments and a radiation-weighting factor for alpha particles of about ten are used. (orig.)

  7. Behavior toxicity to Caenorhabditis elegans transferred to the progeny after exposure to sulfamethoxazole at environmentally relevant concentrations

    Institute of Scientific and Technical Information of China (English)

    Zhenyang Yu; Lei Jiang; Daqiang Yin

    2011-01-01

    Sulfamethoxazole (SMX) is one of the most common detected antibiotics in the environment. In order to study whether SMX can affect behavior and growth and whether these effects could be transferred to the progeny, Caenorhabditis elegans was exposed at environmentally relevant concentrations for 24, 48, 72 and 96 hr, respectively. After exposure, the exposed parent generation (Po) was measured for behavior and growth indicators, which were presented as percentage of controls (POC). Then their corresponding unexposed progeny (F1) was separated and measured for the same indicators. The lowest POC for Po after 96 hr-exposure at 100 mg/L were 37.8%, 12.7%, 45.8% and 70.1% for body bending frequency (BBF), reversal movement (RM), Omega turns (OT) and body length (BL), respectively. And F1 suffered defects with the lowest POC as 55.8%, 24.1%, 48.5% and 60.7% for BBF, RM, OT and BL, respectively. Defects in both Po and F1 showed a time- and concentration-dependent fashion and behavior indicators showed better sensitivity than growth indicator. The observed effects on F1 demonstrated the transferable properties of SMX. Defects of SMX at environmental concentrations suggested that it is necessary to perform further systematical studies on its ecological risk in actual conditions.

  8. Radiation exposure and radon levels in some stations of the Syrian gas company

    International Nuclear Information System (INIS)

    Al-Masri, M. S.; Shwekani, R.; Jerbi, B.; Awad, I.

    2006-06-01

    In the present study, exposure levels and radon concentrations have been measured in natural gas production lines at the Syrian gas company. The study area includes gas stations for directories of Der Ezzor, Al-Jbessa, Al-Hassaka, and the middle region. The results showed that radiation exposure rates in remote stations and internal stations were within the natural levels except for two main locations, viz reflex pumps and propane production unites; 3 μSvhr -1 was reported. Radon concentration in Syrian natural gas varied between 15.4 Bqm - 3 and 1141 Bqm - 3; coproduced natural gas was found to contain higher concentration that the free natural gas. In addition, radon concentrations were higher in the central processing facilities that the well heads; these high levels are due to pressurizing and concentrating processes that enhance radon gas and its daughters concentrations in these stations. Moreover, a value of 659 Bqm - 3 in Al-Jbessa directorate gas and 225 Bqm - 3 in Al-Hassaka directorate gas were reported. While the concentration was lower in gas producing safur; a value of 80 Bqm - 3 was observed. On the other hand, maximum radon gas concentrations and its daughters in workplace air environment was found to be relatively high in the gas analysis laboratory and they are due to gas release inside the lab during analysis in addition to good separation of these laboratories from the surrounding environment. (author)

  9. Residential radon exposure and lung cancer risk in Misasa, Japan. A case-control study

    International Nuclear Information System (INIS)

    Sobue, Tomotaka; Lee, Valerie S.; Ye, Weimin; Tanooka, Hiroshi; Mifune, Masaaki; Suyama, Akihiko; Koga, Taeko; Morishima, Hiroshige; Kondo, Sohei

    2000-01-01

    In order to investigate an association between residential radon exposure and risk of lung cancer, a case-control study was conducted in Misasa Town, Tottori Prefecture, Japan. The case series consisted of 28 people who had died of lung cancer in the years 1976-96 and 36 controls chosen randomly from the residents in 1976, matched by sex and year of birth. Individual residential radon concentrations were measured for 1 year with alpha track detectors. The average radon concentration was 46 Bq/m 3 for cases and 51 Bq/m 3 for controls. Compared to the level of 24 or less Bq/m 3 , the adjusted odds ratios of lung cancer associated with radon levels of 25-49, 50-99 and 100 or more Bq/m 3 , were 1.13 (95% confidence interval; 0.29-4.40), 1.23 (0.16-9.39) and 0.25 (0.03-2.33), respectively. None of the estimates showed statistical significance, due to small sample size. When the subjects were limited to only include residents of more than 30 years, the estimates did not change substantially. This study did not find that the risk pattern of lung cancer, possibly associated with residential radon exposure, in Misasa Town differed from patterns observed in other countries. (author)

  10. Radon

    Science.gov (United States)

    ... in recognizing, evaluating, and treating illnesses resulting from exposure to hazardous substances. top Email Print Share Add this to... Favorites Del.icio.us Digg Facebook Google Bookmarks Yahoo MyWeb Page last reviewed: March ...

  11. Is exposure to over ground radon as dangerous as they say?

    International Nuclear Information System (INIS)

    Krishan Kant

    2007-01-01

    Complete text of publication follows. Natural sources of radioactivity are all around us, and man-made radioactive materials are a vital part of medicine and industry. Exposure to some radiation, natural or man-made, is inevitable. Sixty-eight percent of our exposure to natural sources of radiation usually comes from radon, a colorless, tasteless, and odorless gas that comes from the decay of uranium found in nearly all soils. Radioactive radon gas is widely considered to be a health hazard by environmental agencies in the United States and in Europe. Yet despite the warnings of these agencies, thousands of people annually expose themselves to radon for therapeutic purposes, in facilities ranging from rustic old mines, to upscale spas and clinics. Moreover, while modern biomedicine has been enormously successful in the treatment of acute illnesses, it has dealt less well with chronic illnesses. In living with radiation, we must understand the risks and benefits. In order to assess the risk at high doses, LNT hypothesis of ICRP (and consequently also of IAEA, EU, NCRP, BEIR VI, etc.) is used. Current radiation risk estimates, drawn by linear extrapolation, from high dose and dose rate of radiation from very high and complex miner's data orders of magnitude down to completely different current mining conditions, residential radon doses and dose-rates, and a multitude of other confounding factors, even very careful epidemiological studies have not demonstrated any cancerogenic radon effects up to levels around 1000 Bq/m 3 , or ca. 7 times the EPA limit. This paper addresses the possibility that the LNT model may not be applicable for low doses of radon, and that low doses of radon may in fact be beneficial for certain chronic illnesses. There are growing numbers of studies indicating an inverse relationship between cancer occurrence and low dose environmental radon exposure, as well as numerous studies examining the therapeutic effects of low dose radiation. This

  12. Radon exposure in abandoned metalliferous mines of South America

    Energy Technology Data Exchange (ETDEWEB)

    Silva, A.A.R. da; Umisedo, N.; Yoshimura, E.M. [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica. Lab. de Dosimetria; Anjos, R.M. [Universidade Federal Fluminense (LARA/UFF), Niteroi, RJ (Brazil). Inst. de Fisica. Lab. de Radioecologia; Valladares, D.L.; Velasco, H.; Rizzotto, M. [Universidad Nacional de San Luis (UNSL) (Argentina). Inst. de Matematica Aplicada San Luis

    2011-07-01

    Since the days of the Spanish and Portuguese conquerors, South America has been closely associated with the metalliferous ore mining. Gold, silver, tin, lead, tungsten, nickel, copper, and palladium ores have been explored over the last centuries. In addition, there has also been the development and promotion of other economic activities related to mining, as the underground mine tourism. A few works have been published on radon levels in the South American mining. In this study, we investigated the radon transport process and its health hazard in two exhausted and abandoned mines in San Luis Province, Argentina. These mines were chosen because they have different physical configurations in their cavities, features which can affect the air flow patterns and radon concentrations. La Carolina gold mine (32 deg 48' 0'' S, 66 deg 60' 0'' W) is currently a blind end system, corresponding to a horizontal excavation into the side of a mountain, with only a main adit. Los Condores wolfram mine (32 deg 33' 25'' S, 65 deg 15' 20'' W) is also a horizontal excavation into the side of a mountain, but has a vertical output (a shaft) at the end of the main gallery. Three different experimental methodologies were used. Radon concentration measurements were performed by CR-39 nuclear track detectors. The distribution of natural radionuclide activities ({sup 40}K, {sup 232}Th and {sup 238}U) was determined from rock samples collected along their main adits, using in laboratory gamma-ray spectrometry. The external gamma dose rate was evaluated using thermoluminescent dosimeters and a portable survey meter. The values for the {sup 222}Rn concentration ranged from 0.43 {+-} 0.04 to 1.48 {+-} 0.12 kBq/m{sup 3} in the Los Condores wolfram mine and from 1.8 {+-} 0.1 to 6.0{+-}0.5 kBq/m{sup 3} in the La Carolina gold mine, indicating that, in this mine, the radon levels exceed up to four times the action level of 1.5 kBq/m{sup 3

  13. Domestic Radon Exposure and Risk of Childhood Cancer: A Prospective Census-Based Cohort Study

    NARCIS (Netherlands)

    Hauri, D.; Spycher, B.; Huss, A.; Zimmermann, F.; Grotzer, M.; von der Weid, N.; Weber, D.; Spoerri, A.; Kuehni, C.E.; Röösli, M.

    2013-01-01

    Background: In contrast with established evidence linking high doses of ionizing radiation with childhood cancer, research on low-dose ionizing radiation and childhood cancer has produced inconsistent results.Objective: We investigated the association between domestic radon exposure and childhood

  14. Estimation of past radon exposure to indoor radon from embedded 210Po in household glass

    International Nuclear Information System (INIS)

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

    2012-01-01

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

  15. Quantification of lung cancer risk after low radon exposure and low exposure rate: synthesis from epidemiological and experimental data

    International Nuclear Information System (INIS)

    Timarche, M.

    2004-03-01

    Radon is a radioactive gas produced during the decay of uranium 238 that is present in soil. It was classified as a human lung carcinogen in 1988, based on evidence both from animal studies and from human studies of miners with high levels of radon exposure. Radon is present everywhere; therefore the quantification of the risk associated with exposure to it is a key public health issue. The project aimed to analyse the risk associated with radon inhalation at low doses and at low rates of exposure. It involved researchers from three different fields: epidemiology, animal experiments and mechanistic modelling and provided a unique opportunity to study the influence of dose rate, mainly in the range of low daily exposures over long periods, by analysing in parallel results from both animal and epidemiological studies. The project comprised 6 work packages (W.P.). Firstly, the partners involved in epidemiology and animal experiments worked on the validation and the analysis of the data. Secondly, the data from W.P.1 and W.P.4 were transferred to the partners involved in W.P.5 for the application of mechanistic models. In the final step a synthesis of the results was prepared. (N.C)

  16. Quantification of lung cancer risk after low radon exposure and low exposure rate: synthesis from epidemiological and experimental data

    Energy Technology Data Exchange (ETDEWEB)

    Timarche, M

    2004-03-15

    Radon is a radioactive gas produced during the decay of uranium 238 that is present in soil. It was classified as a human lung carcinogen in 1988, based on evidence both from animal studies and from human studies of miners with high levels of radon exposure. Radon is present everywhere; therefore the quantification of the risk associated with exposure to it is a key public health issue. The project aimed to analyse the risk associated with radon inhalation at low doses and at low rates of exposure. It involved researchers from three different fields: epidemiology, animal experiments and mechanistic modelling and provided a unique opportunity to study the influence of dose rate, mainly in the range of low daily exposures over long periods, by analysing in parallel results from both animal and epidemiological studies. The project comprised 6 work packages (W.P.). Firstly, the partners involved in epidemiology and animal experiments worked on the validation and the analysis of the data. Secondly, the data from W.P.1 and W.P.4 were transferred to the partners involved in W.P.5 for the application of mechanistic models. In the final step a synthesis of the results was prepared. (N.C)

  17. Current status of programmes to measure and reduce radon exposure in Irish workplaces

    Energy Technology Data Exchange (ETDEWEB)

    Colgan, P A; Madden, J S; Synnott, H; Fennell, S; Pollard, D; Fenton, D [Radiological Protection Institute of Ireland, 3 Clonskeagh Square, Dublin 14(Ireland)

    2004-06-01

    National legislation, which implements European Council Directive 96/29/EURATOM in Ireland, sets a reference level of 400 Bq m{sup -3} averaged over any 3 month period for radon exposure in the workplace and also empowers the Radiological Protection Institute of Ireland to direct employers to have radon measurements carried out. This legislation came into effect in May 2000. Radon measurements have already been completed in show caves and other underground workplaces. Between 1998 and 2001, over 33 800 individual radon measurements were carried out in all ground floor offices and classrooms in 3444 schools nationwide as part of a programme undertaken jointly with the Department of Education and Science. Where the average indoor radon concentration in one or more rooms exceeded 200 Bq m{sup -3}, remedial measures were implemented. For concentrations up to 400 Bq m{sup -3} this involved increased ventilation while for higher concentrations an active sump was normally installed. The results of the survey, as well as the effectiveness of the different remedial strategies, are discussed. In the case of other above ground workplaces, different approaches have been adopted. As a first step, workplaces in two known high radon areas were directed to have radon measurements carried out. This programme had limited success because of problems in obtaining accurate workplace databases and a general lack of awareness on the part of employers of the issues involved. From a sample of 2610 employers directed to measure radon, only 408 actually completed measurements and 37 workplaces were identified as having average 3 month average radon concentrations above 400 Bq m{sup -3}. A total of 1356 employers ignored all correspondence, some of which was sent by registered post and signed for on receipt. Current initiatives are focused on the provision of information and include newspaper advertising as well as publications aimed specifically at both employer and employee representative

  18. The radon in Corsica: evaluation of exposure and associated risks; Le radon en Corse: evaluation de l'exposition et des risques associes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-02-15

    The average level found in Corsica is superior to that one found in France. On the basis of the results of it campaign I.R.S.N.-D.G.S., the French average is of 90 Bq.m{sup 3} against 197 Bq.m{sup 3} for Corsica. The risk of dying from a lung cancer attributable to the radon was estimated at 13 % in France. The evaluation of risk led on Corsica shows a risk attributable to the radon included between 21.5 and 28 %.This evaluation of risk is only a stage. It is important to arrest better the exposure to the radon of the Corsican population. For a good estimation of the levels of radon and thus the impact of this one, additional measures are necessary. The results of the data analysis of exposure allow to guide the choice of the new measures: a campaign on the season effect in Corsica and a completion of the measures in housing are two main axes.Seen the importance of the interaction between the tobacco and the radon, a good estimation of the tobacco customs in Corsica and its evolution in the time seems essential to estimate indeed the impact of the radon in this region. (N.C.)

  19. Cleaners in reducing the hazards of indoor radon decay products

    International Nuclear Information System (INIS)

    Montassier, N.; Hopke, P.K.; Shi, Y.; Wasiolek, P.; McCallum, B.

    1992-01-01

    The objective of this study was to evaluate the influence of three types of air cleaners on the concentration and size distribution of radon progeny in a normally occupied house. Using an automated, semi-continuous, graded-screen array system and a radon monitor, the activity size distribution and radon concentration was measured and the exposure of the occupants of the home to radon could be assessed. The dose model developed as part of the recently released U.S. National Academy of Sciences report was used to related the exposure to deposited dose in the tissue of the bronchial epithelium. Thus, the effectiveness of the air cleaners in reducing both exposure and dose were evaluated. (author)

  20. Modelling radiation exposure in homes from siporex blocks by using exhalation rates of radon

    Directory of Open Access Journals (Sweden)

    Nikolić Mladen D.

    2015-01-01

    Full Text Available Building materials are the second major source of indoor radon, after soil. The contribution of building materials to indoor radon amount depends upon the radium content and exhalation rates, which can be used as a primary index for radon levels in the dwellings. This paper presents the results of using the experimentally determined exhalation rates of siporex blocks and concrete plates, to assess the radiation exposure in dwellings built of siporex blocks. The annual doses in rooms have been estimated depending on the established modes of ventilation. Realistic scenario was created to predict an annual effective dose for an old person, a housewife, a student, and an employed tenant, who live in the same apartment, spending different periods of time in it. The results indicate the crucial importance of good ventilation of the living space.

  1. Sex and smoking sensitive model of radon induced lung cancer

    International Nuclear Information System (INIS)

    Zhukovsky, M.; Yarmoshenko, I.

    2006-01-01

    Radon and radon progeny inhalation exposure are recognized to cause lung cancer. Only strong evidence of radon exposure health effects was results of epidemiological studies among underground miners. Any single epidemiological study among population failed to find reliable lung cancer risk due to indoor radon exposure. Indoor radon induced lung cancer risk models were developed exclusively basing on extrapolation of miners data. Meta analyses of indoor radon and lung cancer case control studies allowed only little improvements in approaches to radon induced lung cancer risk projections. Valuable data on characteristics of indoor radon health effects could be obtained after systematic analysis of pooled data from single residential radon studies. Two such analyses are recently published. Available new and previous data of epidemiological studies of workers and general population exposed to radon and other sources of ionizing radiation allow filling gaps in knowledge of lung cancer association with indoor radon exposure. The model of lung cancer induced by indoor radon exposure is suggested. The key point of this model is the assumption that excess relative risk depends on both sex and smoking habits of individual. This assumption based on data on occupational exposure by radon and plutonium and also on the data on external radiation exposure in Hiroshima and Nagasaki and the data on external exposure in Mayak nuclear facility. For non-corrected data of pooled European and North American studies the increased sensitivity of females to radon exposure is observed. The mean value of ks for non-corrected data obtained from independent source is in very good agreement with the L.S.S. study and Mayak plutonium workers data. Analysis of corrected data of pooled studies showed little influence of sex on E.R.R. value. The most probable cause of such effect is the change of men/women and smokers/nonsmokers ratios in corrected data sets in North American study. More correct

  2. Sex and smoking sensitive model of radon induced lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Zhukovsky, M.; Yarmoshenko, I. [Institute of Industrial Ecology of Ural Branch of Russian Academy of Sciences, Yekaterinburg (Russian Federation)

    2006-07-01

    Radon and radon progeny inhalation exposure are recognized to cause lung cancer. Only strong evidence of radon exposure health effects was results of epidemiological studies among underground miners. Any single epidemiological study among population failed to find reliable lung cancer risk due to indoor radon exposure. Indoor radon induced lung cancer risk models were developed exclusively basing on extrapolation of miners data. Meta analyses of indoor radon and lung cancer case control studies allowed only little improvements in approaches to radon induced lung cancer risk projections. Valuable data on characteristics of indoor radon health effects could be obtained after systematic analysis of pooled data from single residential radon studies. Two such analyses are recently published. Available new and previous data of epidemiological studies of workers and general population exposed to radon and other sources of ionizing radiation allow filling gaps in knowledge of lung cancer association with indoor radon exposure. The model of lung cancer induced by indoor radon exposure is suggested. The key point of this model is the assumption that excess relative risk depends on both sex and smoking habits of individual. This assumption based on data on occupational exposure by radon and plutonium and also on the data on external radiation exposure in Hiroshima and Nagasaki and the data on external exposure in Mayak nuclear facility. For non-corrected data of pooled European and North American studies the increased sensitivity of females to radon exposure is observed. The mean value of ks for non-corrected data obtained from independent source is in very good agreement with the L.S.S. study and Mayak plutonium workers data. Analysis of corrected data of pooled studies showed little influence of sex on E.R.R. value. The most probable cause of such effect is the change of men/women and smokers/nonsmokers ratios in corrected data sets in North American study. More correct

  3. Epidemiological study on the cancer mortality in an area with elevated radon daughter exposure

    International Nuclear Information System (INIS)

    Pohl-Rueling, J.

    1983-07-01

    In many countries water containing considerable amounts of Radon-222 is used in so-called ''Radon Spas'' for therapeutical purposes. In the Austrian radon spas Badgastein and Bad Hofgastein many detailed studies of the environmental natural radioactivity have been carried out for about 20 years. The accumulated annual doses to the basal cells of the segmental and subsegmental bronchiols (receiving the highest dose at inhalation of radon and daughters, and target for lung cancer) were calculated for several population groups in this area. The researcher calculated the exposure to radon and daughter accumulated over a lifetime for each single person who lived in Badgastein for at least 10 years and died between 1947 and 1980. The lifetime bronchial doses of 1366 residents who died between 1947 and 1980 from several causes of death were calculated. Altogether 56 lung cancer cases occurred. From that the annual lung cancer incidence rate for Badgastein (30 and 108 per 10 5 living people of all ages and for persons over 40 years respectively) is not statistically different from the mean observed lung cancer cases in the whole Federal Province of Salzburg (32 and 98 respectively). A case-control study has also been carried out to compare the mean annual lifetime exposure of lung cancer deaths with those of other. It can be seen that for the higher exposed population groups and even more so for the miners, the persons who died of lung cancer received a higher dose than those who died of other cancer and other causes. Therefore radon daughter inhalation may be responsible for lung cancer induction even in a non-mining environment

  4. Calibration of SSNDT detectors for radon measurements

    International Nuclear Information System (INIS)

    Takahashi, Laura C.; Santos, Talita O.; Pinheiro, Rose Mary M.; Rocha, Zildete

    2017-01-01

    The methods and instrumentation used to measure the concentration of radon need to be calibrated to obtain accurate results. The Nuclear Track Detector is considered the main method of analysis of radon research. Thus, the Natural Radioactivity Laboratory of the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG, Brazil) uses the detector CR-39 (Landauer) to measure the concentration of radon in homes, workplaces, underground mines, soils and in environment. Epidemiological studies reveal the strong relationship between lung cancer and radon exposure. Therefore, it is important to monitor this gas and its progeny in order to assess the radiological risk. The alpha particles emitted by radon and its progeny leave traces on CR-39 due to Coulombian interactions with the atoms of the material. The liquid density of traces is converted to radon concentration by means of a calibration factor obtained in calibrated systems. This work aims to determine the LRN / CDTN calibration factor. To do so, the CR-39 detectors were placed inside the calibration chambers, along with two AlphaGUARD (Saphymo GmbH) detectors and Ra-266 sources with activities of 3,379 kBq or 0.483 kBq, referenced by NIST. From this, six levels of exposure were obtained, which were: 44 kBq.d.m 3 , 4 kBq.d.m 3 , 3 kBq.d.m 3 , 15 kBq.d.m 3 , 30 kBq.d.m 3 , 26 kBq.d.m 3 . The conversion factor between the liquid density of traces and the total exposure time obtained was K = 52.028 ± 0.752 [(trace density.cm -2 ) / (kBq.d.m -3 )]. After the determination of the conversion factor, it was used to measure the concentration of radon in underground mines, obtaining concentration results between 122 ± 24 and 7384 ± 517 kBq.m -3

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

    International Nuclear Information System (INIS)

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

    1989-01-01

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

  6. Radon in the indoor environment

    International Nuclear Information System (INIS)

    Vanmarcke, H.

    1998-01-01

    The objectives of R and D on radon in the indoor environment at SCK-CEN is to (1) to investigate the deposition of radon progeny in the human respiratory tract by means of direct measurements as a function of aerosol conditions; to assess the radon concentrations in buildings retrospectively with volume traps. Progress and main achievements in 1997 are reported on

  7. Radon and health

    International Nuclear Information System (INIS)

    Chobanova, Nina

    2016-01-01

    Radon is radioactive noble gas that can be found in soil, water, outdoor and indoor air. Since environmental radon on average accounts for about half of all human exposure to radiation from natural sources, increasing attention has been paid to exposure to radon and its associated health risks. Many countries have introduced regulations to protect their population from radon in dwellings and workplaces. In this article are discussed main characteristics of radon, including sources of exposure, variation in radon exposure, how managing risks from radon exposure, how to measure the concentration of radon. There are results of measurements conducted under the 'National radon programme' in Bulgaria also. Key words: radon, sources of exposure, risk, cancer, measure to decrease the concentration [bg

  8. Exposure to radon in the Gadime Cave, Kosovo.

    Science.gov (United States)

    Bahtijari, M; Vaupotic, J; Gregoric, A; Stegnar, P; Kobal, I

    2008-02-01

    Air radon concentration was measured in summer and winter at 11 points along the tourist guided route in the Gadime Cave in Kosovo using alpha scintillation cells and etched track detectors. At two points in summer, values higher than 1700Bqm(-3) were observed; they otherwise were in the range 400-1000Bqm(-3). Values were lower in winter. The effective dose received by a person during a 90min visit is 3.7microSv in summer and 2.5microSv in winter. For a tourist guide the annual effective dose is less than 3.5mSv.

  9. Exposure to radon in the Gadime Cave, Kosovo

    International Nuclear Information System (INIS)

    Bahtijari, M.; Vaupotic, J.; Gregoric, A.; Stegnar, P.; Kobal, I.

    2008-01-01

    Air radon concentration was measured in summer and winter at 11 points along the tourist guided route in the Gadime Cave in Kosovo using alpha scintillation cells and etched track detectors. At two points in summer, values higher than 1700 Bq m -3 were observed; they otherwise were in the range 400-1000 Bq m -3 . Values were lower in winter. The effective dose received by a person during a 90 min visit is 3.7 μSv in summer and 2.5 μSv in winter. For a tourist guide the annual effective dose is less than 3.5 mSv

  10. Exposure to radon in the Gadime Cave, Kosovo

    Energy Technology Data Exchange (ETDEWEB)

    Bahtijari, M. [Faculty of Education, University of Prishtina, Prishtina, Kosovo (Country Unknown); Vaupotic, J.; Gregoric, A.; Stegnar, P. [Jozef Stefan Institute, PO Box 3000, 1001 Ljubljana (Slovenia); Kobal, I. [Jozef Stefan Institute, PO Box 3000, 1001 Ljubljana (Slovenia)], E-mail: ivan.kobal@ijs.si

    2008-02-15

    Air radon concentration was measured in summer and winter at 11 points along the tourist guided route in the Gadime Cave in Kosovo using alpha scintillation cells and etched track detectors. At two points in summer, values higher than 1700 Bq m{sup -3} were observed; they otherwise were in the range 400-1000 Bq m{sup -3}. Values were lower in winter. The effective dose received by a person during a 90 min visit is 3.7 {mu}Sv in summer and 2.5 {mu}Sv in winter. For a tourist guide the annual effective dose is less than 3.5 mSv.

  11. Radon exposure and mortality among the French cohort of uranium miners: 1946-1999

    International Nuclear Information System (INIS)

    Vacquier, B.; Tirmarche, M.; Laurier, D.; Caer, S.; Quesne, B.

    2006-01-01

    Full text of publication follows: The French cohort of uranium miners aims at evaluating the mortality risk of miners exposed to low levels of radon and its decay products and to other occupational hazards. Its primary aim is the quantification of the relationship between cumulated radon exposure and the risk of lung cancer death. However this study also allows to analyse risks for causes of death other than lung cancer. We present a new analysis of the mortality based on an extended follow-up of the cohort to end of 1999. Materials and methods: The French cohort of uranium miners has been followed by the Institut de Radioprotection et de Surete Nucleaire (I.R.S.N.) since the 1980's, in collaboration with the Occupational Medical Service of Compagnie Generale des Matieres Nucleaires (Cogema). The cohort was recently enlarged and the follow-up extended up to 1999. It includes men employed as miners for at least 1 year since 1946 at the Commissariat a l Energie Atomique (Cea) or at the Cogema. Individual vital status was ascertained through a national database and causes of death were determined according to death certificates. For each miner, yearly radon exposures was reconstructed and expressed in working level month (W.L.M.). Risk of death was estimated relatively to external reference rates from the general French male population. The classical method of standardized mortality ratios (S.M.R.s) was used to adjust for age and calendar year. Exposure-risk relationships have been estimated by Poisson regression, using a linear excess relative risk (E.R.R.) model with a lag time of 5 years. Results: The cohort comprises 5,098 miners. The mean duration of follow -up is 30.1 years (total of 153,272 person-years). The number of radon exposed miners is 4,134 with an average cumulative radon exposure of 36.5 W.L.M.. Miners lost to follow-up represent 1.4% of the cohort. A total of 1,471 deaths before age 85 is observed up to 1999. The analysis shows no excess for all

  12. Radon Exposures in the Caves of Tenerife (Canary Islands)

    International Nuclear Information System (INIS)

    Pinza-Molina, C.; Alcaide, J.M.; Rodriques-Bethencourt, R.; Hernandez-Armas, J.

    1999-01-01

    There are more than a hundred volcanic caves and pits of various lengths on the island of Tenerife (Canary Islands, Spain). The results are presented of atmospheric radon measurements performed in three of these caves and in three pits. One of the caves selected, El Viento Cave, is nearly 20 km in length and is the longest volcanic tube in the Canarian archipelago and the second longest in the world. The measurements were performed over two distinct periods during the year using passive polycarbonate detectors. The mean radon concentrations range between 0.3 and 8 kBq.m -3 , the maximum value corresponds to a site located at 1850 m from the mouth of El Viento Cave. Possible touristic development of these caves has been taken into account in estimating the effective doses for visitors and guides (considered separately). The values obtained range from 0.3 to 100 μSv per visit for visitors. The largest effective dose would correspond to that for guides at 41 mSv.y -1 in the Viento Cave. This result would make protection against radiological hazards obligatory if the cave were to be developed as a site for tourism. (author)

  13. Neurobehavioral Effects of Sodium Tungstate Exposure on Rats and Their Progeny

    National Research Council Canada - National Science Library

    Mclnturf, S. M; Bekkedal, M. Y; Olabisi, A; Arfsten, D; Wilfong, E; Casavant, R; Jederberg, W; Gunasekar, P. G; Chapman, G

    2007-01-01

    ... consequences of exposure. The purpose of this study was to use a battery of tests as an initial screen for potential neurobehavioral effects that may be associated with 70 days of daily tungsten exposure via drinking water...

  14. Lung cancer incidence after exposure of rats to low doses of radon: influence of dose rate

    Energy Technology Data Exchange (ETDEWEB)

    Morlier, J.P.; Morin, M.; Monchaux, G.; Fritsch, P.; Lafuma, J.; Masse, R. [CEA Centre d`Etudes Nucleaires de Fontenay-aux-Roses, 92 (France). Dept. de Protection Technique; Pineau, J.F. [ALGADE, Bessines (France); Chameaud, J. [Compagnie Generale des Matieres Nucleaires (COGEMA), 87 - Razes (France)

    1994-12-31

    To study the effect on lung cancer incidence of a long exposure to low levels of radon, 500 male 3-months-old Sprague-Dawley rats, were exposed to a cumulative dose of 25 WLM of radon and its daughters, 6 hours a day, 5 days a week, during 18 months. Exposure conditions were controlled in order to maintain a defined PAEC: 42 x 10{sup 6} J.m{sup -3} (2 WL), in the range of domestic and environmental exposures. Animals were kept until they died or given euthanasia when moribund. Mean survival times were similar in both irradiated and control groups: 828 days (SD = 169) and 830 days (SD = 137), as well as lung cancer incidence, 0.60% at 25 WLM and 0.63% for controls. The incidence of lung lesions was compared statistically with controls and those previously obtained at cumulative exposures of 25 and 50 WLM delivered over a 4-6 month period, inducing a significant increase of lung cancer, 2.2% and 3.8% respectively. Such a comparison showed a decreased lung cancer incidence related to a decrease in the dose rate for low levels of radon exposure. (author).

  15. Lung cancer incidence after exposure of rats to low doses of radon: influence of dose rate

    International Nuclear Information System (INIS)

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

    1994-01-01

    To study the effect on lung cancer incidence of a long exposure to low levels of radon, 500 male 3-months-old Sprague-Dawley rats, were exposed to a cumulative dose of 25 WLM of radon and its daughters, 6 hours a day, 5 days a week, during 18 months. Exposure conditions were controlled in order to maintain a defined PAEC: 42 x 10 6 J.m -3 (2 WL), in the range of domestic and environmental exposures. Animals were kept until they died or given euthanasia when moribund. Mean survival times were similar in both irradiated and control groups: 828 days (SD = 169) and 830 days (SD = 137), as well as lung cancer incidence, 0.60% at 25 WLM and 0.63% for controls. The incidence of lung lesions was compared statistically with controls and those previously obtained at cumulative exposures of 25 and 50 WLM delivered over a 4-6 month period, inducing a significant increase of lung cancer, 2.2% and 3.8% respectively. Such a comparison showed a decreased lung cancer incidence related to a decrease in the dose rate for low levels of radon exposure. (author)

  16. Radon programme: presence and future

    International Nuclear Information System (INIS)

    Hulka, J.

    2009-01-01

    In this presentation an overview of radon programme experiences is presented. The paper summarises national radon policy, national programmes, legislation, the role of preventive measures and interventions with respect to existing and future exposure and knowledge of radon risk, problems of remediation strategies, practical protection in dwellings, radon measurements strategies, progress in radon measurement of an individual house (radon diagnosis), radon mapping process and sense of delineation of radon prone areas, natural radioactivity of building materials and radioactivity in public water and their role in the radon programme, public awareness on radon issue and publicity campaign. Some research activities are proposed aiming at effective solutions of radon issues in future

  17. Study on radon and thoron levels in different types of granitic work industries around Tumkur city

    International Nuclear Information System (INIS)

    Nagabhushan, S.R.; Ningappa, C.; Srilatha; Shekar, Usha; Sannappa, J.

    2011-01-01

    Radon is a naturally occurring radioactive noble gas generated by the decay of uranium and thorium bearing minerals in rocks, soils and building materials. Radon and decay products are the major contributors to human exposure from natural radiation sources. Epidemiological evidence indicates that indoor radon and thoron were responsible for a substantial number of lung cancer in publics. UNSCEAR reported recently indicates that there is a remarkable coherence between the risk estimates developed from epidemiological studies from miners and residential case-control radon studies. Hence to select the study area for the estimation of dose due to radon and thoron to the publics and workers, concentration of radon, thoron and their progeny were measured by using SSNTD. Since, activity concentration in granite more, higher concentrations of radon and thoron have been observed in the dwellings near to granite industry and lesser concentration of radon and thoron have been observed in the dwellings near brick industries of Tumkur city. From the study, the concentration of radon and thoron varied from 31 to 70.4 Bq.m 3 and 11.6 to 46.3 Bq.m 3 , respectively. Corresponding progeny level varied from 0.11 to 2.5 mWL and 1.1 to 3.4 mWL, respectively. (author)

  18. Development of an electronic monitor for the determination of individual radon and thoron exposure

    Energy Technology Data Exchange (ETDEWEB)

    Irlinger, Josef

    2015-06-11

    The carcinogenic effect of the radio isotope {sup 222}Rn of the noble gas radon and its progeny, as well as its residential distribution, are well studied. In contrast, the knowledge about the effects and average dwelling concentration levels of its radio isotope {sup 220}Rn (thoron) is still limited. Generally, this isotope has been assumed to be a negligible contributor to the effective annual dose. However, only recently it has been pointed out in several international studies, that the dose due to thoron exceeds the one from {sup 222}Rn under certain conditions. Additionally, radon monitors may show a considerable sensitivity towards thoron which was also not accounted for in general. Therefore a reliable, inexpensive exposimeter, which allows to distinguish between decays of either radon and thoron, is required to conduct further studies. The scope of this thesis was to develop an electronic radon/thoron exposimeter which features small size, low weight and minimal power consumption. The design is based on the diffusion chamber principle and employs state-of-the-art alpha particle spectroscopy to measure activity concentrations. The device was optimized via inlet layout and filter selection for high thoron diffusion. Calibration measurements showed a similar sensitivity of the monitor towards radon and thoron, with a calibration factor of cf{sup {sub 2}{sub 2}{sub 2Rn}} = 16.2 ± 0.9 Bq m{sup -3}/cph and cf{sup {sub 2}{sub 2}{sub 0Rn}} = 14.4 ± 0.8 Bq m{sup -3}/cph, respectively. Thus, the radon sensitivity of the device was enhanced by a factor two compared to a previous prototype. The evaluation method developed in this work, in accordance with ISO 11665 standards, was validated by intercomparison measurements. The detection limits for radon and thoron were determined to be C{sup {sub 2}{sub 2}{sub 2Rn}} = 44.0 Bq m{sup -3} and C{sup {sub 2}{sub 2}{sub 0Rn}} = 40.0 Bq m{sup -3}, respectively, in case of a low radon environment, a one-hour measurement

  19. Development of an electronic monitor for the determination of individual radon and thoron exposure

    International Nuclear Information System (INIS)

    Irlinger, Josef

    2015-01-01

    The carcinogenic effect of the radio isotope 222 Rn of the noble gas radon and its progeny, as well as its residential distribution, are well studied. In contrast, the knowledge about the effects and average dwelling concentration levels of its radio isotope 220 Rn (thoron) is still limited. Generally, this isotope has been assumed to be a negligible contributor to the effective annual dose. However, only recently it has been pointed out in several international studies, that the dose due to thoron exceeds the one from 222 Rn under certain conditions. Additionally, radon monitors may show a considerable sensitivity towards thoron which was also not accounted for in general. Therefore a reliable, inexpensive exposimeter, which allows to distinguish between decays of either radon and thoron, is required to conduct further studies. The scope of this thesis was to develop an electronic radon/thoron exposimeter which features small size, low weight and minimal power consumption. The design is based on the diffusion chamber principle and employs state-of-the-art alpha particle spectroscopy to measure activity concentrations. The device was optimized via inlet layout and filter selection for high thoron diffusion. Calibration measurements showed a similar sensitivity of the monitor towards radon and thoron, with a calibration factor of cf 222 Rn = 16.2 ± 0.9 Bq m -3 /cph and cf 220 Rn = 14.4 ± 0.8 Bq m -3 /cph, respectively. Thus, the radon sensitivity of the device was enhanced by a factor two compared to a previous prototype. The evaluation method developed in this work, in accordance with ISO 11665 standards, was validated by intercomparison measurements. The detection limits for radon and thoron were determined to be C 2 22 Rn = 44.0 Bq m -3 and C 2 20 Rn = 40.0 Bq m -3 , respectively, in case of a low radon environment, a one-hour measurement interval, and a background count rate of zero. In contrast, in mixed radon/thoron concentrations where the 212 Po peak must

  20. Estimating the distribution of lifetime cumulative radon exposures for California residents: a brief summary

    International Nuclear Information System (INIS)

    Liu, K.-S.; Chang, Y.-L.; Hayward, S.B.; Gadgil, A.J.; Nero, A.V.

    1992-01-01

    Data on residential radon concentrations in California, together with information on California residents' moving houses and time-activity patterns, have been used to estimate the distribution of lifetime cumulative exposures to 222 Rn. This distribution was constructed using Monte Carlo techniques to simulate the lifetime occupancy histories and associated radon exposures of 10,000 California residents. For standard male and female lifespans, the simulation sampled from transition probability matrices representing changes of residence within and between six regions of California, as well as into and out of the other United States, and then sampled from the appropriate regional (or national) distribution of indoor concentrations. The resulting distribution of lifetime cumulative exposures has a significantly narrower relative width than the distribution of California indoor concentrations, with only a small fraction (less than 0.2%) of the population having lifetime exposures equivalent to living their lifetimes in a single home with a radon concentration of 148 Bq.m -3 or more. (author)

  1. Residential radon exposure and risk of incident hematologic malignancies in the Cancer Prevention Study-II Nutrition Cohort

    Energy Technology Data Exchange (ETDEWEB)

    Teras, Lauren R., E-mail: lauren.teras@cancer.org [Epidemiology Research Program, American Cancer Society, Atlanta, GA (United States); Diver, W. Ryan [Epidemiology Research Program, American Cancer Society, Atlanta, GA (United States); Turner, Michelle C. [Centre for Research in Environmental Epidemiology (CREAL), Barcelona (Spain); Universitat Pompeu Fabra (UPF), Barcelona (Spain); CIBER Epidemiología y Salud Pública (CIBERESP), Madrid (Spain); McLaughlin Centre for Population Health Risk Assessment, University of Ottawa, Ottawa (Canada); Krewski, Daniel [McLaughlin Centre for Population Health Risk Assessment, University of Ottawa, Ottawa (Canada); School of Epidemiology, Public Health and Disease Prevention, University of Ottawa, Ottawa, Ontario (Canada); Sahar, Liora [Statistics and Evaluation Center, American Cancer Society, Atlanta, GA (United States); Ward, Elizabeth [Intramural Research, American Cancer Society, Atlanta, GA (United States); Gapstur, Susan M. [Epidemiology Research Program, American Cancer Society, Atlanta, GA (United States)

    2016-07-15

    Dosimetric models show that radon, an established cause of lung cancer, delivers a non-negligible dose of alpha radiation to the bone marrow, as well as to lymphocytes in the tracheobronchial epithelium, and therefore could be related to risk of hematologic cancers. Studies of radon and hematologic cancer risk, however, have produced inconsistent results. To date there is no published prospective, population-based study of residential radon exposure and hematologic malignancy incidence. We used data from the American Cancer Society Cancer Prevention Study-II Nutrition Cohort established in 1992, to examine the association between county-level residential radon exposure and risk of hematologic cancer. The analytic cohort included 140,652 participants (66,572 men, 74,080 women) among which 3019 incident hematologic cancer cases (1711 men, 1308 women) were identified during 19 years of follow-up. Cox proportional hazard regression was used to calculate multivariable-adjusted hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) for radon exposure and hematologic cancer risk. Women living in counties with the highest mean radon concentrations (>148 Bq/m{sup 3}) had a statistically significant higher risk of hematologic cancer compared to those living in counties with the lowest (<74 Bq/m{sup 3}) radon levels (HR=1.63, 95% CI:1.23–2.18), and there was evidence of a dose-response relationship (HR{sub continuous}=1.38, 95% CI:1.15–1.65 per 100 Bq/m{sup 3}; p-trend=0.001). There was no association between county-level radon and hematologic cancer risk among men. The findings of this large, prospective study suggest residential radon may be a risk factor for lymphoid malignancies among women. Further study is needed to confirm these findings. - Highlights: • This is the first prospective, general population study of residential radon and risk of hematologic cancer. • Findings from this study suggest that residential radon exposure may be a risk factor

  2. Residential radon exposure and risk of incident hematologic malignancies in the Cancer Prevention Study-II Nutrition Cohort

    International Nuclear Information System (INIS)

    Teras, Lauren R.; Diver, W. Ryan; Turner, Michelle C.; Krewski, Daniel; Sahar, Liora; Ward, Elizabeth; Gapstur, Susan M.

    2016-01-01

    Dosimetric models show that radon, an established cause of lung cancer, delivers a non-negligible dose of alpha radiation to the bone marrow, as well as to lymphocytes in the tracheobronchial epithelium, and therefore could be related to risk of hematologic cancers. Studies of radon and hematologic cancer risk, however, have produced inconsistent results. To date there is no published prospective, population-based study of residential radon exposure and hematologic malignancy incidence. We used data from the American Cancer Society Cancer Prevention Study-II Nutrition Cohort established in 1992, to examine the association between county-level residential radon exposure and risk of hematologic cancer. The analytic cohort included 140,652 participants (66,572 men, 74,080 women) among which 3019 incident hematologic cancer cases (1711 men, 1308 women) were identified during 19 years of follow-up. Cox proportional hazard regression was used to calculate multivariable-adjusted hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) for radon exposure and hematologic cancer risk. Women living in counties with the highest mean radon concentrations (>148 Bq/m 3 ) had a statistically significant higher risk of hematologic cancer compared to those living in counties with the lowest (<74 Bq/m 3 ) radon levels (HR=1.63, 95% CI:1.23–2.18), and there was evidence of a dose-response relationship (HR continuous =1.38, 95% CI:1.15–1.65 per 100 Bq/m 3 ; p-trend=0.001). There was no association between county-level radon and hematologic cancer risk among men. The findings of this large, prospective study suggest residential radon may be a risk factor for lymphoid malignancies among women. Further study is needed to confirm these findings. - Highlights: • This is the first prospective, general population study of residential radon and risk of hematologic cancer. • Findings from this study suggest that residential radon exposure may be a risk factor for lymphoid

  3. Wire-mesh capped deposition sensors: Novel passive tool for coarse fraction flux estimation of radon thoron progeny in indoor environments

    International Nuclear Information System (INIS)

    Mayya, Y.S.; Mishra, Rosaline; Prajith, Rama; Sapra, B.K.; Kushwaha, H.S.

    2010-01-01

    Deposition-based 222 Rn and 220 Rn progeny sensors act as unique, passive tools for determining the long time-averaged progeny deposition fluxes in the environment. The use of these deposition sensors as progeny concentration monitors was demonstrated in typical indoor environments as conceptually superior alternatives to gas-based indirect monitoring methods. In the present work, the dependency of these deposition monitors on various environmental parameters is minimized by capping the deposition sensor with a suitable wire mesh. These wire-mesh capped deposition sensors measure the coarse fraction deposition flux, which is less dependent on the change in environmental parameters like ventilation rate and turbulence. The calibration of these wire-mesh capped coarse fraction progeny sensors was carried out by laboratory controlled experiments. These sensors were deployed both in indoor and in occupational environments having widely different ventilation rates. The obtained coarse fraction deposition velocities were fairly constant in these environments, which further confirmed that the signal on the wire-mesh capped sensors show the least dependency on the change in environmental parameters. This technique has the potential to serve as a passive particle sizer in the general context of nanoparticles using progeny species as surrogates. On the whole, there exists a strong case for developing a passive system that responds only to coarse fraction for providing alternative tools for dosimetry and environmental fine particle research. - Research highlights: → Wire-mesh capped deposition sensor measures the coarse fraction deposition flux → Coarse fraction deposition flux less dependent on environmental conditions → Wire-mesh capped deposition sensor as passive particle sizer

  4. Exposure to radon and mortality standard in a coal miner cohort in Brazil

    International Nuclear Information System (INIS)

    Veiga, Lene Holanda Sadler; Amaral, Eliana; Koifman, Sergio

    2002-01-01

    High levels of radon and his products have been found at a underground coal mine, at the Southern Brazil, in operation since 1945. The 222 Rn concentration levels measured were 7000 Bq/m 3 and 0.7 WL for the radon sons (7.7 WLM/year), which are values considered higher than the limits for intervention in a working environments (500 to 1500 Bq/m3 of 222 Rn) and the occupational exposure limit (4.0 WLM/year). Due to the unique opportunity found in these miner group, it was decided to construct a cohort with miners from that mining (underground and surface) viewing the evaluation of the possible effects to the health decurrens from that exposure

  5. National campaign of measurement of domestic exposure to radon IPSN-DGS

    International Nuclear Information System (INIS)

    Gailliez, E.

    2000-10-01

    The radon atlas in accommodation, published by the Institute of Nuclear Protection and Safety (I.P.S.N.) and the General Direction of Health (D.G.S.), and available from http://www.ipsn.fr, presents maps and statistical elements from 12 641 measures made in 10013 communes, from 1982 up to and including 1999. The objective pursued is to estimate in an overall way the French population exposure to domestic radon. An update is planned regularly (every two years). In its present version, the modesty of the measures number and the local strong disparities make very difficult the identification of risk areas at the communal level: high voluminal activities can be noticed in any commune; whereas a housing situated in a commune classified in the highest group will not show inescapably a strong concentration in radon leading to take rapid measures. The average value of radon voluminal activity measured in France is 90 Bq. by m 3 . For the risk management, the authorities have kept the value of 400 Bq. by m 3 as caution objective and this one of 1000 Bq. by m 3 as alert threshold, in yearly average value. (N.C.)

  6. Aspects of practical radiation protection in professional and non-professional exposure in radon spas

    International Nuclear Information System (INIS)

    Steger, F.

    1986-04-01

    The radiation protection legislation is generally based on the assumption of a linear dose-response relationship for stochastic effects, and of a dose-threshold for non stochastic effects, following a recommendation of the ICRP. The linear-dose-response relationship for the low dose range - and therefore for the exposure in Radon spas - is generally accepted. The paper discusses the consequences of this assumption and suggests guidlines for the practical performance of radiation protection in such locations. (Author)

  7. A comparison of the exposure response of French and Irish radon detectors during field measurements in houses in Brittany

    International Nuclear Information System (INIS)

    Tymen, G.; Mouden, A.; McLaughlin, J.P.; Wasiolek, P.; Rannou, A.

    1988-01-01

    Intercomparisons between French (CEA) and Irish (UCD) radon detectors were made during 1986/87 under field conditions in over 100 dwellings within the framework of a regional study in Britanny which commenced in 1984. Two different types of passive radon detectors, both using Kodak-Pathe LR-115 film, were used. The French type is of the open variety while the Irish type is closed. Preliminary analysis of the results obtained from about one hundred exposures shows that while good agreement was found in some cases a mean relative variation of 40% appears to exist between the French and Irish data. In general the Irish data gave the lower radon determinations. Likely reasons for any lack of agreement between the radon data sets obtained from the passive detectors are discussed and also comparisons are made in relation to potential alpha energy data, gamma exposure data and the exposure conditions in the dwellings. (author)

  8. Radon and its decay products in living spaces: estimation of radiation exposure and risks for radon levels measured in Switzerland

    International Nuclear Information System (INIS)

    Burkart, W.

    1984-03-01

    After a general introduction to radiation levels, radon and its daughter products are considered. Radon in living spaces is discussed, in particular the radon concentration in family houses. The influence of energy saving characteristics on the radon concentration in the indoor air includes a 'matched pair' analysis and ventilation installations and dwell duration of indoor air noxious agents. Estimation of the radiation risks are determined, including risks of lung cancer, human epidemiological investigations (miners and radiation levels in living spaces), and possible results of energy saving characteristics. Finally characteristics and recommendations in general are given. (A.N.K.)

  9. Investigation of the various factors affecting the response of passive configuration track etch dosimeters to working level hour exposure in radon and radon daughter atmospheres. Final report

    International Nuclear Information System (INIS)

    Lovett, D.B.

    1976-01-01

    The work described in this report was directed toward identifying and devising methods to minimize the previously observed variability between working level hour exposures and the alpha particle track densities resulting on Track Etch films exposed to mine atmospheres containing radon and radon daughters. The disequilibrium between radon and its daughters was shown to directly affect the Track Etch film calibration factor. The wide range of disequilibrium states possible in mine situations amply explains the variability in the previous tests. A file of published mine atmosphere composition data was compiled and was used, along with atmospheric compositions derived from several theoretical models of the atmospheric behavior, to evaluate the variability of several dosimeter configurations and concepts

  10. Measurement of size distribution for 220Rn progeny attached aerosols

    International Nuclear Information System (INIS)

    Zhang Lei; Guo Qiuju; Zhuo Weihai

    2008-01-01

    The size distribution of radioactive aerosols is a very important factor for evaluating the inner exposure dose contributed by radon and thoron progeny in environments. In order to measure the size distribution of thoron progeny attached radioactive aerosols, a device was developed using wire screens. The count median diameter (CMD) and the geometric standard deviation (GSD) of attached radioactive aerosols were calculated by collecting ThB and using CR-39 as detector. Field measurement results at Yangjiang City in Guangdong Province show that the CMDs distribute between 30 and 130 nm, and the GSDs are between 1.9 and 3.3. It also shows that the more humid country, the smaller CMDs, and the ventilation has great influence on the size distribution of aerosols. The CMDs of adobe house are smaller than that of the concrete houses. (authors)

  11. The radon

    International Nuclear Information System (INIS)

    1998-01-01

    This booklet is intended to answer briefly the most important questions about the nature and sources of radon, its pathways from environment to organism, as well as the ways to minimize its concentration in the habitat's atmosphere. The radon is a naturally appearing radioactive gas, produced through the decay of uranium and radium present in the terrestrial crust. It can be found everywhere on the planet's surface and it is emitted particularly from the granite and volcanic underground rocks as well as from certain construction materials. It is one of the agents producing pulmonary cancer, although not so dangerous as the tobacco is. The following items are elaborated in this booklet: - the place of radon in the average exposure to ionizing radiations of the French population; - the risk; - the radon in the environment (the meteorological conditions, the nature of the rocks); - radon in dwellings (radon measurements in the French dwellings, the entrance pathways of radon, the dependence of radon concentration on the profession and way of life of the inhabitants); - radon measurements; - how to reduce the radon concentration in dwellings

  12. The determined exposures by radon in uran ore mining by WISMUT are artifacts; Die ermittelten Radon-Expositionen im Uran-Erzbergbau der WISMUT sind Artefakte

    Energy Technology Data Exchange (ETDEWEB)

    Eigenwillig, Gerd Georg

    2017-04-01

    The uranium ore mining by WISMUT in Object 09 in Saxony and the inhalation exposure by radon ({sup 222}Rn) and its decay products in 1956 are used as example. Measurement results are not available any more. Ultimately only one arithmetic mean is used - a single value for hewer. This single value and models/concepts are applied to estimate exposures for thousands of underground workers. The result of the procedure are artifacts with unknown uncertainties. Nevertheless the artifacts are used uncritically.

  13. Gestational exposure to diethylstilbestrol alters cardiac structure/function, protein expression and DNA methylation in adult male mice progeny

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, Rami, E-mail: rami.haddad@mail.mcgill.ca [Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 chemin Cote Ste Catherine, Montréal, Québec, Canada H3T 1E2 (Canada); Division of Experimental Medicine, Department of Medicine, McGill University, 850 Sherbrooke Street, Montréal, Québec, Canada H3A 1A2 (Canada); Kasneci, Amanda, E-mail: amanda.kasneci@mail.mcgill.ca [Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 chemin Cote Ste Catherine, Montréal, Québec, Canada H3T 1E2 (Canada); Mepham, Kathryn, E-mail: katherine.mepham@mail.mcgill.ca [Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 chemin Cote Ste Catherine, Montréal, Québec, Canada H3T 1E2 (Canada); Division of Experimental Medicine, Department of Medicine, McGill University, 850 Sherbrooke Street, Montréal, Québec, Canada H3A 1A2 (Canada); Sebag, Igal A., E-mail: igal.sebag@mcgill.ca [Division of Cardiology, Jewish General Hospital, 3755 chemin Cote Ste Catherine, Montréal, Québec, Canada H3T 1E2 (Canada); and others

    2013-01-01

    Pregnant women, and thus their fetuses, are exposed to many endocrine disruptor compounds (EDCs). Fetal cardiomyocytes express sex hormone receptors making them potentially susceptible to re-programming by estrogenizing EDCs. Diethylstilbestrol (DES) is a proto-typical, non-steroidal estrogen. We hypothesized that changes in adult cardiac structure/function after gestational exposure to the test compound DES would be a proof in principle for the possibility of estrogenizing environmental EDCs to also alter the fetal heart. Vehicle (peanut oil) or DES (0.1, 1.0 and 10.0 μg/kg/da.) was orally delivered to pregnant C57bl/6n dams on gestation days 11.5–14.5. At 3 months, male progeny were left sedentary or were swim trained for 4 weeks. Echocardiography of isoflurane anesthetized mice revealed similar cardiac structure/function in all sedentary mice, but evidence of systolic dysfunction and increased diastolic relaxation after swim training at higher DES doses. The calcium homeostasis proteins, SERCA2a, phospholamban, phospho-serine 16 phospholamban and calsequestrin 2, are important for cardiac contraction and relaxation. Immunoblot analyses of ventricle homogenates showed increased expression of SERCA2a and calsequestrin 2 in DES mice and greater molecular remodeling of these proteins and phospho-serine 16 phospholamban in swim trained DES mice. DES increased cardiac DNA methyltransferase 3a expression and DNA methylation in the CpG island within the calsequestrin 2 promoter in heart. Thus, gestational DES epigenetically altered ventricular DNA, altered cardiac function and expression, and reduced the ability of adult progeny to cardiac remodel when physically challenged. We conclude that gestational exposure to estrogenizing EDCs may impact cardiac structure/function in adult males. -- Highlights: ► Gestational DES changes cardiac SERCA2a and CASQ2 expression. ► Echocardiography identified systolic dysfunction and increased diastolic relaxation. ► DES

  14. Measurement of unattached aerosols of 222 Rn progeny by means of an electrostatic deposition method

    International Nuclear Information System (INIS)

    Canoba, Analia C.; Lopez, Fabio O.

    2001-01-01

    A method for the measurement of unattached radon progeny based on its electrostatic deposition onto wire screens, using only one pump, has been implemented and calibrated. The importance of being able of making use of this method is related with the special radiological significance that has the unattached fraction of the short-lived radon progeny. Because of this, the assesment of exposure could be directly related to dose with far greater accuracy than before.The advantages of this method are its simplicity, even with the tools needed for the sample collection, as well as the measurement instruments used. Also, the suitability of this method is enhanced by the fact that it can effectively be used with a simple measuring procedure such as the Kusnetz method. (author)

  15. Radon-induced cancer: a cell-based model of tumorigenesis due to protracted exposures

    International Nuclear Information System (INIS)

    Elkind, M.M.

    1994-01-01

    In 1982, results with C3H mouse embryo cells showed that the frequency of neoplastic transformation was enhanced when exposures to fission-spectrum neutrons were protracted in time. This finding was unexpected because the opposite was found with low-LET radiations. Similar neutron enhancements were reported with normal life-span Syrian hamster embryo cells, and with human hybrid cells. Because other studies did not confirm the preceding, in 1990 - at a conference convened by the US Armed Forces Radiobiological Research Institute - a biophysical model was proposed to explain the basis for the enhancement observed in some experiments but not in others. The model attributed special sensitivities, related to killing and neoplastic transformation, to cells in and around mitosis. Subsequently, it was shown that late G 2 /M phase cells constituted this window of sensitivity. In the instance of tumorigenesis, the model predicted that protracted exposures to a high-LET radiation would result in enhanced frequencies of transformation providing that susceptible cells were cycling or could be induced to cycle. The model explained data on lung tumour induction in rats breathing radon at different concentrations, and uranium miners working in atmospheres containing different concentrations of radon. The model also explains the anomalous finding that lung cancer deaths are often sublinearly correlated with indoor radon concentration. (author)

  16. Indoor radiation exposures from radon and its daughters: a view of the issue

    International Nuclear Information System (INIS)

    Nero, A.V. Jr.

    1981-08-01

    Exposure to radon daughters indoors can result in significant risk to the general public, particularly those living in homes with much higher than average concentrations. This paper reviews what is known about indoor concentrations, associated risks, and the effect of measures to save energy by reducing ventilation rates. It concludes that, by employing appropriate control measures in homes having unacceptably high concentrations, the average exposure (and therefore risk) of the general public can remain at its present level, or even decrease, despite programs to save energy by tightening homes

  17. Radon in workplaces

    International Nuclear Information System (INIS)

    Gooding, Tracy

    1995-01-01

    The naturally occurring radioactive gas radon has been found at excessive levels in many workplaces other than mines throughout the country. Prolonged exposure to radon and its decay products increases the risk of developing lung cancer, and controls to protect employees from excessive exposure are included in the Ionising Radiations Regulations 1985. The control of occupational exposure to radon is discussed here. (author)

  18. Transient gestational exposure to drinking water containing excess hexavalent chromium modifies insulin signaling in liver and skeletal muscle of rat progeny.

    Science.gov (United States)

    Shobana, Navaneethabalakrishnan; Aruldhas, Mariajoseph Michael; Tochhawng, Lalmuankimi; Loganathan, Ayyalu; Balaji, Sadhasivam; Kumar, Mani Kathiresh; Banu, Liaquat Alikhan Sheerin; Navin, Ajit Kumar; Mayilvanan, Chinnaiyan; Ilangovan, Ramachandran; Balasubramanian, Karundevi

    2017-11-01

    Chromium (Cr), an essential micronutrient potentiates insulin action, whereas excess hexavalent Cr (CrVI) acts as an endocrine disruptor. Pregnant mothers living in areas abutting industries using the metal and chromite ore dumps are exposed to ground water contaminated with Cr. Nevertheless, the impact of prenatal exposure to excess CrVI on insulin signaling in the progeny remains obscure. We tested the hypothesis "transient gestational exposure to drinking water containing excess CrVI may modify insulin signaling during postnatal life". Pregnant Wistar rats were given drinking water containing 50, 100 and 200 ppm CrVI (K 2 Cr 2 O 7 ) from gestational day 9-14 encompassing the period of organogenesis; the male progenies were tested at postnatal day 60. Neither fasting blood glucose nor oral glucose tolerance was altered in CrVI treated progeny. Nevertheless, western blot detection pointed out attenuated expression level of insulin receptor (IR), its downstream signaling molecules (IRS-1, pIRS-1 Tyr632 , Akt and pAkt Ser473 ) and organ specific glucose transporters (GLUT2 in liver and GLUT4 in gastrocnemius muscle), along with a significant increase in serum insulin level in male progenies exposed to CrVI. While 14 C-2-deoxy glucose uptake increased in the liver, the same decreased in the skeletal muscle whereas, 14 C-glucose oxidation recorded a consistent decrease in both tissues of CrVI exposed rats. These findings support our hypothesis and suggest that transient gestational exposure to excess CrVI may affect insulin signaling and glucose oxidation in the progeny, predictably rendering them vulnerable to insulin resistance. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Joint analysis of French and Czech uranium miners: lung cancer risk at low radon exposure rates and modifying effects of time since exposure and age at exposure

    International Nuclear Information System (INIS)

    Ladislav Tomasek; Agnes Rogel; Margot Tirmarche; Dominique Laurier

    2006-01-01

    The present analysis was conducted in the frame of European project 'Quantification of lung cancer risk after low radon exposure and low exposure rate: synthesis from epidemiologic and experimental data'. The overall goal of the project related to uranium miners was the evaluation of lung cancer dose-response relationship and of dose rate effects among European uranium miners exposed to low doses and low dose rates of radon decay products. In addition, modifying factors like attained age, age at exposure and time since exposure were investigated. The joint analysis of French and Czech uranium miners was conducted mainly in order to increase the statistical power and to allow a more detailed description of the variation of dose-response relationship in time. (N.C.)

  20. Joint analysis of French and Czech uranium miners: lung cancer risk at low radon exposure rates and modifying effects of time since exposure