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Sample records for residential radon daughter

  1. Residential radon daughter monitor based on alpha spectroscopy

    International Nuclear Information System (INIS)

    Nazaroff, W.W.

    1980-05-01

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

  2. Personal radon daughter dosimetry

    International Nuclear Information System (INIS)

    Stocker, H.

    1979-12-01

    The conventional means of radon daughter exposure estimatikn for uranium miners in Canada is by grab sampling and time weighting. Personal dosimetry is a possible alternative method with its own advantages and limitations. The author poses basic questions with regard to two methods of radon daughter detection, thermoluminescent chips and track-etch film. An historical review of previous and current research and development programs in Canada and in other countries is presented, as are brief results and conclusions of each dosimeter evaluation

  3. Passive radon daughter dosimeters

    International Nuclear Information System (INIS)

    McElroy, R.G.C.; Johnson, J.R.

    1986-03-01

    On the basis of an extensive review of the recent literature concerning passive radon daughter dosimeters, we have reached the following conclusions: 1) Passive dosimeters for measuring radon are available and reliable. 2) There does not presently exist an acceptable passive dosimeter for radon daughters. There is little if any hope for the development of such a device in the foreseeable future. 3) We are pessimistic about the potential of 'semi-passive dosimeters' but are less firm about stating categorically that these devices cannot be developed into a useful radon daughter dosimeter. This report documents and justifies these conclusions. It does not address the question of the worker's acceptance of these devices because at the present time, no device is sufficiently advanced for this question to be meaningful. 118 refs

  4. Radon and radon daughter monitoring (including thoron daughter monitoring)

    International Nuclear Information System (INIS)

    Leach, V.A.; Grealy, G.; Gan, W.

    1982-01-01

    Radon/radon daughter and thoron daughter measurement techniques are outlined. The necessary precautions and critical assessments of each method are also presented with a view to providing a better understanding of the various measurement methods

  5. Radon daughter dosimeter

    International Nuclear Information System (INIS)

    Durkin, J.

    1977-01-01

    This patent describes a portable radon daughter dosimeter unit used to measure radon gas alpha daughters in ambient air. These measurements can then be related to preselected preestablished standards contained in a remote central readout unit. The dosimeter unit is adapted to be worn by an operator in areas having alpha particle radiation such as in uranium mines. Within the dosimeter is a detector head housing having a filter head and a solid state surface barrier radiation detector; an air pump to get air to the detector head; a self contained portable power supply for the unit; and electronic circuitry to process detected charged electrons from the detector head to convert and count their pulses representatives of two alpha radon emitter daughters. These counted pulses are in binary form and are sent to a readout unit where a numerical readout displays the result in terms of working level-hours

  6. Radon daughter dosimeter

    International Nuclear Information System (INIS)

    Durkin, J.

    1977-01-01

    A portable radon daughter dosimeter unit used to measure Radon gas alpha daughters in ambient air is described. These measurements can then be related to preselected preestablished standards contained in a remote central readout unit. The dosimeter unit is adapted to be worn by an operator in areas having alpha particle radiation such as uranium mines. Within the dosimeter is a detector head housing having a filter head and a solid state surface barrier radiation detector; an air pump to get air to the detector head; a self contained portable power supply for the unit; and electronic circuitry to process detected charged electrons from the detector head to convert and count their pulses representatives of two alpha radon emitter daughters. These counted pulses are in binary form and are sent to a readout unit where a numerical readout diplays the result in terms of working level-hours

  7. Prevention of lung cancer by remediation of residential exposure to radon daughters

    International Nuclear Information System (INIS)

    Mahaffey, J.A.; Cross, F.T.; Johnson, J.R.; Baechler, M.C.

    1991-01-01

    The United States Bonneville Power Administration (BPA), as part of an energy conservation programme in the states of Washington, Oregon, Idaho, Wyoming, and Montana, has collected over 36,000 residential radon concentration measurements. Data were collected between 1983 and 1989 with ambient α etched track dosemeters. Based on the linear risk coefficient from the BEIR IV report for lifetime lung cancer in smokers and non-smokers, numbers of lung cancer cases attributable to radon exposure were predicted. Numbers of baseline lung cancer cases and numbers of these that were preventable by remediation were also estimated. Remediation to 10 pCi.1 -1 , to 4 pCi.1 -1 , and to outdoor levels were considered. With vital statistics data, results were extrapolated to populations in the states represented by the BPA data. Costs of remediation were estimated. Results were evaluated in terms of cost per cancer saved and per cent reduction in fatal lung cancer cases from the baseline estimate. (author)

  8. Updating radon daughter bronchial dosimetry

    International Nuclear Information System (INIS)

    Harley, N.H.; Cohen, B.S.

    1990-01-01

    It is of value to update radon daughter bronchial dosimetry as new information becomes available. Measurements have now been performed using hollow casts of the human bronchial tree with a larynx to determine convective or turbulent deposition in the upper airways. These measurements allow a more realistic calculation of bronchial deposition by diffusion. Particle diameters of 0.15 and 0.2 μm were used which correspond to the activity median diameters for radon daughters in both environmental and mining atmospheres. The total model incorporates Yeh/Schum bronchial morphometry, deposition of unattached and attached radon daughters, build up and decay of the daughters and mucociliary clearance. The alpha dose to target cells in the bronchial epithelium is calculated for the updated model and compared with previous calculations of bronchial dose

  9. Effectiveness of air vapor barriers combined with ventilated crawlspaces in decreasing residential exposure to radon daughters to radon daughters: preliminary report

    International Nuclear Information System (INIS)

    Sterling, T.D.; Arundel, A.; McIntyre, D.; Sterling, E.; Sterling, T.D.

    1986-01-01

    Radon gas is present in many homes. Concentrations may be increased in airtight, energy-efficient structures. This is especially true in cold climates where energy conservation is an important factor leading to the widespread application of sealing and tightening techniques both in older renovated homes and new construction. To reduce radon concentrations, it may be effective to ventilate crawlspaces and prevent infiltration of radon gas into the house by means of an air/vapor barrier. The authors report first results of comparing radon levels in homes with and without ventilated crawlspaces and air/vapor barriers. Radon emissions were measured in a tightly sealed home with ventilated crawlspaces and an air/vapor barrier and in two homes without such vapor barriers and ventilated crawlspaces, but differing in ventilation. Preliminary results suggest that use of ventilated crawlspaces and bottomside vapor barriers may reduce indoor radon levels by approximately 60%. 15 references, 1 table

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

    International Nuclear Information System (INIS)

    1983-01-01

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

  11. Efficient measurement of radon daughters

    International Nuclear Information System (INIS)

    Rolle, R.

    1992-01-01

    In environmental control there is an increasing need for efficient measurement of radon and thoron daughters in air. Measuring instruments should be rugged and portable for field use, while also permitting unattended operation for several days. Simple operating procedures should permit evaluation of rapidly changing concentrations over extended periods. These requirements demand careful balance in the design of hardware and measuring procedures. The design principles for a continuous flow-through spectrometer, that has been developed for precision sequential measurement of radon and thoron daughters, are described. Because of the high precision of measurement, this type of instrument should find application in environments from technologically enhanced natural radiation to the very lowest natural background situations. (author)

  12. Radon and its daughters in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Rundo, J

    1984-05-01

    Prolonged exposure to radon should build up a reservoir of radon in body fat and fluids. If the subject moved to an environment with a lower radon concentration from an environment with a higher level of radon, the result would be an exhalation of radon, and the initial exhalation rate of radon should depend of the radon concentration inhaled. This paper describes the behavior of radon and its daughters in vivo and a relationship between the radon exhalation rate and the time after a meal. A major but short-lived postprandial increase in the exhalation rate of radon was observed. The author reports a similar effect in the exhalation rate of radon by persons containing no radium. It should be noted that the possibility exists that a large amount of radon daughters in the chest may interfere in the investigation of possible internal contamination with plutonium or other actinides by external counting. 8 figures.

  13. Radon and its daughters in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Rundo, J

    1984-05-01

    Prolonged exposure to radon should build up a reservoir of radon in body fat and fluids. Movement of the subject to an environment with a lower radon concentration from an environment with a higher level of radon would result in an exhalation of radon, and the initial exhalation rate of radon should depend on the radon concentration inhaled. This paper describes the behavior of radon and its daughters in vivo and a relationship between the radon exhalation rate and the time after a meal. A major but short-lived postprandial increase in the exhalation rate of radon was observed. We report a similar effect in the exhalation rate of radon by persons containing no radium. It should be noted that the possibility exists that a large amount of radon daughters in the chest may interfere in the investigation of possible internal contamination with plutonium or other actinides by external counting. (author).

  14. Background concentrations of radon and radon daughters in Canadian homes

    International Nuclear Information System (INIS)

    McGregor, R.G.; Vasudev, P.; Letourneau, E.G.; McCullough, R.S.; Prantl, F.A.; Taniguchi, H.

    1980-01-01

    Measurements of radon and radon daughters were carried out in 14 Canadian cities on a total of 9999 homes selected in a statistically random manner. The geometric means of the different cities varied from 0.14 to 0.88 pCi/l. for radon and 0.0009 to 0.0036 Working Levels for radon daughters. The radon originates from natural radioactivity in the soil surrounding the homes. (author)

  15. Predicting radon/radon daughter concentrations in underground mines

    International Nuclear Information System (INIS)

    Leach, V.A.

    1984-01-01

    A detailed description of a computer programme is outlined for the calculation of radon/radon daughter concentrations in air. This computer model is used to predict the radon/radon daughter concentrations in Working Level (WL) at the workplace and at the various junctions at either end of the branches in a typical ventilation network proposed for the Jabiluka mine in the Northern Territory

  16. Orphan radon daughters at Denver Radium site

    International Nuclear Information System (INIS)

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

    1992-01-01

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

  17. Radon and its daughters in vivo

    International Nuclear Information System (INIS)

    Rundo, J.

    1983-01-01

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

  18. Control of radon daughters in underground mining

    International Nuclear Information System (INIS)

    Swent, L.W.

    1983-01-01

    This paper discusses technical developments that may enable uranium mine operators to improve engineering controls of radon daughter concentrations in mines, and developments in regulatory controls. The origin of radon daughters in underground mines is explained. The procedure for sampling and determining the concentration of alpha radiation in sampled air is reviewed. The principal technical development in the last few years has been the perfection and use of a class of meters which determine radon daughter concentrations in an air sample in a matter of two or three minutes without any aging period. A number of underground uranium mine operators are now using ''instant'' type meters and the Mine Safety and Health Administration (MSHA) has approved their use in a number of mines. The difficulty experienced by uranium mine operators in complying with a MSHA regulation which requires that no person be exposed to radon daughter concentrations exceeding 1 Working Level (WL) in any active working place is discussed

  19. Perspective on cancer and radon daughters

    International Nuclear Information System (INIS)

    Archer, V.E.

    1981-01-01

    This paper discusses the hazards from radon and its daughters in the environment and the role they may play in contributing to the general cancer burden. Only in exceptional circumstances can one pick out one mutagen or one carcinogen and scientifically determine what its contribution is o our burden of birth defects and cancer. The risks associated with radon and its daughters are examined in light of this philosophy

  20. Unattached radon daughter atoms and radon daughter equilibrium ratios in uranium mines. Final report

    International Nuclear Information System (INIS)

    Holaday, D.A.

    1972-01-01

    Uranium mines in Colorado and New Mexico were surveyed for airborne concentrations of radon (10043922) and radon daughters. A procedure for measuring individual daughters and the fraction of each existing as free atoms was developed and used for field monitoring. Samples were taken in working areas and particle counts were made. The data was analyzed to determine the ratio of radon to radon daughters as well as the ratios among the radon daughters. The author concludes that since the radon to working level ratios have not changed much in 20 years, using the ratio as the basis for estimating relative biological hazard is just as uncertain now as then. The large number of daughters present as free atoms indicate that the lung radiation doses calculated using any of the lung models need reexamination

  1. Radon/radon-daughter measurement methods and instrumentation

    International Nuclear Information System (INIS)

    Rock, R.L.

    1977-01-01

    Radon-daughter measurement equipment and techniques have been continuously improved over the last 25 years. Improvements have been in the areas of accuracy, time and convenience. We now have miniaturized scalers and detectors available for measuring the alpha particle count rates from aerosol samples collected on filter papers. We also have small lightweight efficient pumps for conveniently collecting samples and we have various counting methods which allow us to choose between making very precise measurements or nominal measurements. Radon-daughter measurement methods used in uranium mines and mills are discussed including a personal radon-daughter-exposure integrating device which can be worn by miners

  2. Compact detector for radon and radon daughter products

    International Nuclear Information System (INIS)

    Alter, H.W.; Oswald, R.A.

    1986-01-01

    This invention provides an improved compact track registration detector for radon gas. The detector comprises a housing having an open mouth, a bottom, and side walls; track registration means, supported inside the housing, which forms damage tracks along paths traversed by alpha particles; a microporous filter positioned across the mouth of the housing to prevent entry of radon daughters and particulate matter; and a cap that may be placed on the mouth of the housing to retain the filter. The housing has internal wall surfaces dimensioned to optimize the registration of alpha particles from radon and radon daughters present in the housing

  3. Contribution of radon and radon daughters to respiratory cancer

    International Nuclear Information System (INIS)

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

    1986-01-01

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

  4. Dosimetry, measurement and properties of radon daughters and thoron daughters

    International Nuclear Information System (INIS)

    Phillips, C.R.

    1982-03-01

    Various properties of radon and thoron daughter products are examined. Dosimeter methods and instrumentation (TLD and personal alpha dosimeters) are investigated as to performance under varying conditions such as humidity and pure or mixed atmospheric conditions. Optimized counting schemes are determined for the daughters of radon and thoron. An optimized counting scheme was experimentally examined under mine conditions. The optimization procedure takes into account the uncertainties associated with concentration, flow rate and radioactive decay. Measurements were made in two uranium mines at Elliot Lake, Ontario of the charged and unattached fractions of radon daughters in the mines. The physicochemical state of 218 Po in air was determined by measurement of rate of neutralization, diffusion coefficient and fraction born charge. Careful control of experimental conditions made it possible to obtain more precise and detailed quantitative data than previously possible

  5. Removal of radon daughters from indoor air

    International Nuclear Information System (INIS)

    Jonassen, N.

    1985-01-01

    The internal radiological exposure of the general population is largely due to the airborne daughter products of radon and thoron, which are found in two states, attached to aerosols or unattached, of which the latter species according to several dose models have the highest radiological dose efficiency of the two. The radon daughters may be removed from indoor air by a series of processes like ventilation, filtration, plateout, and electrostatic deposition. Ventilation (with radon-free air) is, on the one hand, a very effective measure, but usually involves introduction of colder air, in variance with energy-saving efforts. Internal filtration will not affect the radon concentration but may reduce the level of daughter activities, roughly inversely proportional to the filtration rate. At the same time, however, filtration may also change the aerosol distribution and concentration of the air and, consequently, the partitioning of the radon daughters between the attached and unattached state. This, in turn, influences the rate of deposition of radon daughters both by diffusional plateout and as an effect of an electric field. Experiments are reported demonstrating reductions in the airborne potential alpha energy by factors of 4 to 5 by use of filtration rates of 3-4 times per hour. In case of low aerosol concentrations, however, the corresponding reduction in radiological dose to critical parts of the respiratory tract may be much smaller, due to the shift toward higher fractions of the radon daughters being in the unattached state caused by the filtration. The possibility of using electrostatic deposition of radon daughters is also discussed

  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. Construction of radon/radon daughter calibraton chamber

    International Nuclear Information System (INIS)

    Fry, J.; Gan, T.H.; Leach, V.A.; Saddlier, J.; Solomon, S.B.; Tam, K.K.; Travis, E.; Wykes, P.

    1983-01-01

    The radon/radon daughter test chamber is a copper lined room 1.65x1.75x2.75m with an effective volume of 8000 litres. The air residence time is controlled by circulating the air in the chamber through absolute filters which remove 99.9% of particulates. Radon is drawn into the chamber from a 17 μCi 226 RaCl source using the pressure differential across the blowers (<3 psi)

  8. Radon and radon daughters in South African underground mines

    International Nuclear Information System (INIS)

    Rolle, R.

    1980-01-01

    Radon and the radon daughters are the radionuclides which primarily determine the level of the radiation hazard in underground uranium mines and to a smaller extent in non-uranium mines. Radon is a gas, and its daughters adsorb on aerosol particles which are of respirable size. The hazard thus arises from the alpha decay of radon and its daughters in contact with lung tissue. Radon is itself part of the uranium decay chain. The major radionuclide, 238 U, decays successively through thirteen shorter-lived radionuclides to 206 Pb. Radon is the only gaseous decay product at room temperature; the other twelve are solids. The main hazard presented by the uranium decay chain is normally determined by the radon concentration because gaseous transport can bring alpha emitters close to sensitive tissue. There is no such transport route for the other alpha emitters, and the level of beta and gamma radiation caused by the uranium decay chain generally presents a far lower external radiation hazard. Radon itself is the heaviest of the noble gases, which are He, Ne, Ar, Kr, Xe and Rn. Its chemical reactions are of no concern in regard to its potential hazard in mines as it may be considered inert. It does, however, have a solubility ten times higher than oxygen in water, and this can play a significant part in assisting the movement of the gas from the rock into airways. Radon continuously emanates into mine workings from uranium ores and from the uranium present at low concentrations in practically any rock. It has been found that the control of the exposure level is most effectively achieved by sound ventilation practices. In South African mines the standard of ventilation is generally high and exposure to radon and radon daughters is at acceptably low levels

  9. Radon daughters and work at display devices

    International Nuclear Information System (INIS)

    Falk, R.; Nyblom, L.

    1986-01-01

    It has been shown that ions and electrically charged particles in the air can be transported in the electrostatic field between a face and a display device to either the face or the screen. Radon daughters can occur as ions, or sitting on charged particles. This prestudy shows that radon daughters were manifold concentrated on the face of a doll placed in front of a display device, or in a electrostatic field of the kind typical for displaying devices. The radiation dose, in the skin from the radon daughters in an ordinary office environment plus the addition caused by work at a display device, is not strong enough to cause skin damages alone. (BoK)

  10. Workshop on dosimetry for radon and radon daughters

    International Nuclear Information System (INIS)

    Turner, J.E.; Holoway, C.F.; Loebl, A.S.

    1978-05-01

    Emphasis is placed on the dosimetry for radon and daughters, rather than on monitoring and instrumentation. The objectives of the meeting were to exchange scientific information, to identify problem areas in radon-daughter dosimetry, and to make any observations or recommendations by the participants through issuance of this report. The discussion topics included the history of dosimetry for radon and daughters, human data, aerosols, deposition and movement in the respiratory tract, dose calculations, dose-to-working-level-month (WLM) conversion factors, animal experiments, and the development of regulations and remedial criteria for reducing population exposures to radon daughters. This report contains a summary of Workshop discussions plus individual statements contributed by several of the participants. The outstanding problem areas from the standpoint of dosimetry appear to involve the appropriate lung organ mass to be used (average lung-tissue dose vs. high-level local dose); recognition of the discrete, rather than continuous, structure of the mucus; lack of knowledge about lung clearance; the variability of dose with the degree of disequilibrium and the unattached fraction of radon daughters for a given WLM; and questions about the character of uranium mine atmospheres actually breathed in the older mines from which much of the epidemiological information originates. The development of criteria for taking remedial action to reduce exposures involves additional concerns of basing long-term risk assessment on short-term sampling and applying WLM data for miners to general populations

  11. Preliminary evaluation of the control of indoor radon daughter levels in new structures

    International Nuclear Information System (INIS)

    Fitzgerald, J.E. Jr.; Guimond, R.J.

    1976-01-01

    As part of its assessment of the radiological impact of the phosphate industry in Florida, the US Environmental Protection Agency has surveyed residences built atop uraniferous reclaimed phosphate mining land. These surveys have shown elevated radon daughter levels to exist in structures built on this land. In order to allow safer use of this land for residential construction, various state-of-the-art radon daughter control technologies were evaluated by the Agency. These included forced ventilation, polymeric sealants, excavation, crawl space construction, and improved slab quality. From a cost-effectiveness evaluation, improved slab quality and crawl space construction were determined to best satisfy the criteria for optimal radon daughter control

  12. 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.)

  13. 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)

  14. Radon daughter plate-out onto Teflon

    Science.gov (United States)

    Morrison, E. S.; Frels, T.; Miller, E. H.; Schnee, R. W.; Street, J.

    2018-01-01

    Radiopure materials for detector components in rare event searches may be contaminated after manufacturing with long-lived 210Pb produced by the decay of atmospheric radon. Charged radon daughters deposited on the surface or implanted in the bulk of detector materials have the potential to cause noticeable backgrounds within dark matter regions of interest. Understanding the mechanics governing these background signals is therefore a paramount concern in dark matter experiments in order to distinguish a real signal from internal detector backgrounds. Teflon (i.e. PTFE) is a specific material of interest because it makes up the walls of the inner detector of many liquid noble detectors such as the LUX-ZEPLIN experiment. The rate of radon daughter plate-out onto Teflon can be orders of magnitude larger than the plate-out rate onto other materials. Mitigation of plate-out onto Teflon and steel by proximity to other materials is demonstrated.

  15. Application of single-chip microcomputer to portable radon and radon daughters monitor

    International Nuclear Information System (INIS)

    Meng Yecheng; Huang Zhanyun; She Chengye

    1992-01-01

    Application of single-chip microcomputer to portable radon and radon daughters monitor is introduced in this paper. With the single-chip microcomputer automation comes into effect in the process from sampling to measuring of radon and radon daughters. The concentrations of radon and radon daughters can be easily shown when the conversion coefficients are pre-settled before the measurement. Moreover, the principle and design are briefly discussed according to the characteristics of the monitor

  16. 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

  17. [Mutagenicity of radon and radon daughters

    International Nuclear Information System (INIS)

    1990-01-01

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

  18. Radon-daughter chamber instrumentation system reference manual

    International Nuclear Information System (INIS)

    Showalter, R.; Johnson, L.

    1985-01-01

    The radon-daughter chamber instrumentation system collects environmental data from the radon-daughter chamber. These data are then recorded on a Tandberg system tape cartridge and transmitted to the HP-1000 computer for processing. Generators which inject radon and condensation nuclei into the chamber are also included with the instrumentation system

  19. Factors influencing indoor concentrations of radon and daughter products

    International Nuclear Information System (INIS)

    Wang Hengde

    1985-01-01

    The correlation between indoor concentrations of 222 Rn and its daughters and some influencing factors is discussed and expressions of concentrations are derived with relation to radon exhalation rate from indoor surfaces, air exchange rate and daughter deposition velocities on indoor surfaces. Experimental methods for determining radon exhalation rate, air exchange rate and daughter deposition velocities are also mentioned

  20. Comparison of radon and radon-daughter grab samples obtained during the winter and summer

    International Nuclear Information System (INIS)

    Karp, K.E.

    1987-08-01

    The Technical Measurements Center (TMC), under the auspices of the US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) program, is investigating short-term methods for estimating annual average indoor radon-daughter concentrations (RDC). A field study at 40 sample locations in 26 residential structures in Grand Junction, Colorado, was conducted once in the winter and once in the summer. The short-term methods investigated as part of this study include ten-minute radon and radon-daughter grab sampling and hourly RDC measurements. The results of the field study indicate that ten-minute radon grab samples from basement locations are reproducible over different seasons during controlled sampling conditions. Nonbasement radon and RDC grab samples are highly variable even when the use of the location by the occupant is controlled and the ventilation rate is restricted. The grab sampling was performed under controlled occupied conditions. These results confirm that a short-term radon or RDC measurement in a nonbasement location in a house is not a standardized measurement that can be used to infer an annual average concentration. The hourly RDC measurements were performed under three sets of conditions over a 72-hour period. The three sets of conditions were uncontrolled occupied, controlled occupied, and controlled unoccupied. These results indicate that it is not necessary to relocate the occupants during the time of grab sampling. 8 refs., 8 figs., 10 tabs

  1. Working level measurement of radon daughters and thoron daughters by personal dosimetry and continuous monitoring

    International Nuclear Information System (INIS)

    Phillips, C.R.; Leung, H.

    1981-01-01

    The performance of personal alpha dosimeters in mixed radon daughter and thoron daughter atmospheres in Ontario uranium mines is described together with monitoring developments which enable the radon daughter working level to be determined separately. The theoretical bases for continuous and integrated working level measurements based on individual and gross counts are presented in terms of the weighting factor for combining the thoron daughter working level with the radon daughter working level, and in terms of the in-growth time of the air. Implications for the determination of working level in the presence of thoron daughters are discussed

  2. Instrumentation for collecting and measuring radon and its daughters

    International Nuclear Information System (INIS)

    Essling, M.A.; Hengde, W.; Markun, F.; Toohey, R.E.; Rundo, J.; Miranda, J.E. Jr.

    1982-01-01

    A new sampling can is described for collecting an air sample for determination of its radon content. Instruments which are employed for the continuous monitoring of radon or its daughters in houses are described and their performances discussed

  3. Environmental radon and radon daughter dosimetry in the respiratory tract

    International Nuclear Information System (INIS)

    McPherson, R.B.

    1979-04-01

    This report describes work performed by Pacific Northwest Laboratory (PNL) for the Nuclear Regulatory Commission's program to determine safety and costs related to decommissioning nuclear fuel cycle facilities. Individual dose factors for the inhalation of radon and its daughter products are calculated for use in environmental dose assessments. The calculated committed dose equivalent factors for 222 Rn and its daughters are tabulated for lungs, bronchi tract and other organs. An activity median aerodynamic diameter of 0.1 μm was used. The dose to an individual is calculated by multiplying the estimated intake from inhalation for a particular radionuclide by the corresponding dose factor. A working level month-to-dose conversion factor is calculated to be 1 rad/WLM to the epithelial tissue of the T-B region, assuming 100% daughter equilibrium and 10% free 218 Po ions. This value is in reasonable agreement with recently reported values

  4. Health hazards due to radon and its daughters

    International Nuclear Information System (INIS)

    Khan, H.A.; Qureshi, I.E.; Tufail, M.

    1993-01-01

    The health hazards liked to radon and its daughters have become a matter of great public concern. When inhaled, a fraction of radon is dissolved into the lung fluid, from where it is transported to other parts of the body. The radiation damage is caused to the lungs due to alpha decay of radon during its transit time within the respiratory tract. Radon daughters are found to be even more dangerous than radon itself. These daughters attach themselves to dust particles present in the air. Some of the aerosols so produced enter the lungs and enter the blood stream. It has now been confirmed that radon and its daughters contribute about 70% of the internal dose received by an individual from natural radiation sources. The danger of indoor radon and its daughters is even higher for energy-saving houses and those having poor ventilation systems. This paper briefly describes the health hazards due to radon and its daughters. Different methods employed for the measurement of concentrations of radon and their daughters are described. The experience gained from the nation-wide surveys carried out in different countries is also given. (author). 18 refs, 3 figs, 1 tab

  5. Mortality and indoor radon daughter concentrations in 13 Canadian cities

    International Nuclear Information System (INIS)

    Letourneau, E.G.; Wigle, D.T.

    1980-01-01

    A study was carried out to determine if lung cancer and general mortality rates in 13 Canadian cities were significantly correlated with average indoor radon daughter concentrations. The radon daughter measurements were obtained from a study of 10,000 homes chosen in a statistically valid grab sample basis. Cancer deaths by year of death, sex, age, and cause were retrieved for each of the cities for the period 1957-1976. Age specific and age standardized mortality rates were calculated. The results showed no evidence of any substantial association between general or lung cancer mortality rates and indoor radon daughter concentrations. The limitations of this study and the feasibility of a common international program of epidemiology of radon daughter exposure are discussed. A proposal is made for the use of case control studies of lung cancer to assess the relative importance of smoking, occupational and domestic exposure to radon daughters

  6. Residential radon survey in Finland

    International Nuclear Information System (INIS)

    Arvela, H.; Maekelaeinen, I.; Castren, O.

    1993-02-01

    The study measured the indoor radon concentration in the dwellings of 3074 persons, selected randomly from the central population register of Finland. Alpha track detectors and two consecutive half year measuring periods were used. The national mean of indoor radon concentration for persons living in low-rise residential buildings as well as blocks of flats was 145 and 82 Bq/m 3 , respectively. The mean for the total population was 123 Bq/m 3 . Based on the decision of the Ministry of Social Affairs and Health in 1992, the indoor radon concentration should not exceed 400 Bq/m 3 in already existing houses, the target for new construction being less than 200 Bq/m 3 . According to the study, the percentage of the Finnish population living in houses with an indoor radon concentration exceeding 200, 400 and 800 Bq/m 3 was 12.3 %, 3.6 % and 1.0 %

  7. A personal dosemeter of radon daughter products

    International Nuclear Information System (INIS)

    Burian, I.; Richter, M.; Ochec, J.; Dohnal, J.

    1990-01-01

    The OD 88 personal dosemeter for radon daughter products uses an alpha particle track detector and is of active type, with forced air aspiration through the detecting system. The pumping device consists of a miniature membrane pump and an electronic speed controller. The air flow rate is little affected by normal changes in supply voltage and/or pneumatic resistance of the pump circuit. The dosemeter is embedded in a miner's lamp and is fed from its accumulator battery. The pumping device is activated as the lamp is taken out of the charger and deactivated as it is slid into the charger again. The dosemeter head accommodates an AFPC filter on which the radon daughter products deposit. The energy of the alpha particles is reduced by an air layer and a Makrofol decelerating foil. The particles hitting the detector give rise to defects with an intensity proportional to the total linear stopping power at the moment of incidence; ideal tracks 10 μm in size require incident energy of 1.1 to 1.3 MeV. The detector is replaced in a month and worked up in an etching vessel, making use of the higher solubility of the detecting layer of the foil in NaOH at the spot of the alpha particle incidence. (P.A.). 4 figs., 17 refs

  8. Radon and its daughters in various British mines

    International Nuclear Information System (INIS)

    Strong, J.C.; Laidlaw, A.J.; O'Riordan, M.C.

    1975-11-01

    The results of surveys of radon and radon daughter concentrations in a large number of mines, other than coal mines, in Great Britain are presented. Measurement methods are described, and estimates of the average radon daughter concentrations are given. A comparison is made between the results of radon and radon daughter determination. The radon daughter exposure of about 40% of the non-coal miners covered by a survey in 1973 was estimated to be above the recommended limit of 4 WLM in a year. Recommendations were made for reducing this exposure and for radiological surveillance. A follow-up survey shows some improvement partly due to the implementation of these recommendations, and by October 1975, the number of miners estimated to have an annual exposure above the recommended limit had fallen to about 30% of those included in the survey. (author)

  9. New ICRP recommendations on occupational limits for radon daughters

    International Nuclear Information System (INIS)

    Jacobi, W.

    1981-01-01

    The ICRP has recommended in 1959 for the first time a maximum permissible concentration (MPC) for the occupational exposure to radon and its short-lived daughters. Since this time more realistic dosimetric models for radon daughters have been developed. Taking into account epidemiological and new dosimetric findings the ICRP has adopted in March this year new recommendations on occupational limits for inhalation of 222 Rn, 220 Rn and their short-lived daughters. This report will be published this year as ICRP Publication 32 (ICRP 1981). The recommended limits for radon daughters were derived from the basic dose and risk limits as they were proposed by ICRP in its new basic recommendations (ICRP Publ. 26, 1977). In the following this basic system of dose limitation is shortly outlined before the special recommendations for radon daughters are described

  10. 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

  11. Reduction of radon daughter concentrations in structures

    International Nuclear Information System (INIS)

    1982-12-01

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

  12. Indoor radon and radon daughters survey at Campinas-Brazil using CR-39: First results

    International Nuclear Information System (INIS)

    Guedes, S.; Hadler, J.C.N.; Iunes, P.J.; Navia, L.M.S.; Neman, R.S.; Paulo, S.R.; Rodrigues, V.C.; Souza, W.F.; Tello, C.A.S.; Zuniga, A.

    1999-01-01

    The first results of a radon and radon daughters (RD) survey performed at Campinas-SP, Brazil, are presented. We employed a technique that, potentially, makes possible to measure the radon and RD activity in the air and to separate from this result the activity of radon, alone. In this preliminary paper only the former activity is studied

  13. Indoor radon and radon daughters survey at Campinas-Brazil using CR-39: First results

    CERN Document Server

    Guedes, S; Iunes, P J; Navia, L M S; Neman, R S; Paulo, S R; Rodrigues, V C; Souza, W F; Tello, C A S; Zúñiga, A G

    1999-01-01

    The first results of a radon and radon daughters (RD) survey performed at Campinas-SP, Brazil, are presented. We employed a technique that, potentially, makes possible to measure the radon and RD activity in the air and to separate from this result the activity of radon, alone. In this preliminary paper only the former activity is studied.

  14. Second workshop on radon and radon daughters in urban communities associated with uranium mining and processing

    International Nuclear Information System (INIS)

    1979-01-01

    A second meeting of Atomic Energy Control Board staff, federal and provincial government representatives, and consultants was held to discuss progress in reducing the concentrations of radon and its daughter products in houses in communities like Bancroft, Elliot Lake, Port Hope, and Uranium City. Participants discussed successful and unsuccessful remedial techniques, possible sources of radon, and methods of measuring radon and radon daughters in buildings

  15. Doses and affects of radon and its daughters

    International Nuclear Information System (INIS)

    Snihs, J.O.

    1982-01-01

    Radon and its short-lived daughters are one of the main contributors to the natural exposures of ionizing radiation to man. Their sources, levels and characteristics are described. By inhalation of radon and its daughters tissues in the lung are irritated by α-particles leading to an increased risk of lung cancer. Methods of calculation of doses and risks using the dosimetric approach and the epidemiological approach are described and discussed. (Author)

  16. Limitation schemes to decrease the radon daughters in indoor air

    International Nuclear Information System (INIS)

    Swedjemark, G.A.

    1986-01-01

    The limitation schemes to decrease the radon daughter concentrations in Swedish homes are described. The application of the Swedish provisional limitation system in use since 1980 is also reported. As a background the radon source and the international and national recommedations in other countries are reviewed. (author)

  17. Health hazards from radon daughters in dwellings in Sweden

    International Nuclear Information System (INIS)

    Axelson, O.; Edling, C.

    1980-01-01

    To clarify the possible etiological role for lung cancer from exposure to the low levels of radon and its daughters in dwellings, a case-control study was made, comparing cases of lung cancer with controls with respect to residency in different types of houses. This pilot study was restricted to include only people who lived in typically rural areas. The results support the hypothesis that radon and radon daughter exposure in dwellings is pertinent to the question of the etiology of lung cancer

  18. The radon daughter radiation hazard in controlled recirculation systems

    International Nuclear Information System (INIS)

    Rolle, R.; Burton, R.C.

    1987-01-01

    In deep South African gold mines, controlled recirculation systems with air cooling are being used to an increasing extent to improve the thermal environment. Recirculation causes some air to reside in the working area for a longer time than would have occurred without recirculation. Since radon daughters grow spontaneously from radon there is some concern that, with the extended residence time, the potential radiation hazard could increase to an unacceptable level. This paper describes the results obtained from a theoretical model of a controlled recirculation system. Guidelines for the design of recirculation systems to control the radon daughter radiation, and to keep it within acceptable limits are provided. 3 refs., 5 figs

  19. Review of epidemiological studies on hazards of radon daughters

    International Nuclear Information System (INIS)

    Myers, D.K.; Stewart, C.G.; Johnson, J.R.

    1981-01-01

    A review, with nearly 100 references, of the biological effects of radon and radon daughters is presented. Calculations of the relative dose from daughter products, as well as of the variation in dose with such things as unattached fraction, particle size, age and breathing rate are discussed. Estimates of annual risk of lung cancer in miners after inhalation of thoron daughters are given, and compared with hazards of employment in various US industries. The implications of these epidemiological studies for future regulations are discussed

  20. Workshop on radon and radon daughters in urban communities associated with uranium mining and processing

    International Nuclear Information System (INIS)

    1978-01-01

    This meeting of Atomic Energy Control Board staff, representatives of other government departments, and consultants was called to exchange information on steps taken to lower radiation levels in houses in communities such as Elliot Lake, Uranium City, and Port Hope. Discussions covered the sources of radon and radon daughters in these houses, radon measurement techniques, and remedial methods that worked or were not successful

  1. Comparison of two methods for investigating indoor radon daughters

    International Nuclear Information System (INIS)

    Vanmarcke, H.; Raes, F.

    1988-01-01

    The dynamics of radon daughters in realistic indoor environments has been investigated experimentally at the Universities of Gottingen and Gent. Both studies yielded the important result that the fraction of unattached radon daughters is higher than is assumed in earlier studies. Reineking-Porstendorfer and Vanmarcke-Raes adopted quite different methodologies to determine the unattached fraction. In this paper the methodologies are compared by means of joint measurements performed in a house with elevated radon concentrations. The results for the attachment rate, the deposition rate of the unattached daughters and the unattached fraction differ significantly, while the results for the deposition rate of the attached daughters and the equilibrium factor broadly agree. (author)

  2. 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)

  3. Radon and radon daughter measurements at and near the former Middlesex Sampling Plant, Middlesex, New Jersey

    International Nuclear Information System (INIS)

    Haywood, F.F.; Perdue, P.T.; Christian, D.J.; Leggett, R.W.; Dickson, H.W.; Myrick, T.E.

    1980-03-01

    The results of the radon and radon daughter measurements made to date (1978) at the Middlesex Sampling Plant in Middlesex, New Jersey, are presented in this report. These measurements were one portion of a more comprehensive radiological survey conducted at this site and the surrounding area from 1976 to 1978. The surveyed property served as a uranium ore sampling plant during the 1940's and early 1950's and as a result contains elevated levels of surface an subsurface contamination. On-site indoor radon daughter and radon concentrations exceeded both the US Surgeon General Guidelines and the Nuclear Regulatory Commission's maximum permissible concentration limits for radon (10 CFR Part 20) in all structures surveyed. Off-site structures showed concentrations of radon and radon daughters at or only slightly above background levels, except for one site where the radon levels were found to be above the 10 CFR Part 20 guidelines. Outdoor radon ad radon daughter concentrations, measured both on and off the site, were well below the guidelines, and the data give no indication of significant radon transport from the site

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

    International Nuclear Information System (INIS)

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

    1982-12-01

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

  5. Contribution of radon in natural gas to the dose from aiborne radon-daughters in homes

    International Nuclear Information System (INIS)

    Barton, C.J.; Moore, R.E.; Rohwer, P.S.

    1973-01-01

    Data have been obtained on the radon concentration in natural gas supplied to several metropolitan areas in the United States. The average value of 20 pCi/l was selected to estimate the contribution of this source of natural radioactivity to doses from radon-daughters received by individuals in homes. Radon-daughter concentrations in the home atmosphere were calculated by use of computer programs for an 8000 ft 3 house in which 27 ft 3 of gas per day was used for cooking in an unvented kitchen range. The total estimated dose to the bronchial epithelium included contributions from radon plus daughters in the outside ventilation air, each of which was assumed to be present at a concentration of 0.13 pCi/l, and from the radon plus daughters in the natural gas. The latter contribution averaged approximately 3 percent of the total dose. There was a 3.5 percent decrease in the estimated total dose when the air change rate increased from 0.25 to 2.0 per hour. We conclude that radon and radon-daughters entering the home with natural gas produce a negligible fraction of the total dose to the respiratory system of home occupants from airborne radon-daughters

  6. Scavenging of radon daughters by precipitation from the atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Fujinami, Naoto [Kyoto Prefectural Inst. of Hygienic and Environmental Sciences (Japan)

    1997-02-01

    By the continuous measurement of the radon daughters concentration in the rain and snow water and atmosphere and the data analysis, the following results were obtained. The radon daughters concentration was almost constant in the rain and snow water in spite of the length during weather without precipitation. It has not tendency to show the high concentration of radon daughters in precipitation and snow during beginning of them. When the precipitation intensity is constant, it`s concentration does not change during precipitation and snowfall. The concentration does not depend on the amount of precipitation, but on the precipitation intensity. We did not observe a correlation between the radon daughters concentration in the rain and snow water and that in the surface air. The atmospheric concentration was decreased by precipitation and snowfall, but that of rain and snow water did not decrease. The above results seems to show that the contribution of washout under the cloud to radon daughters in rain and snow water is small and that of rainout in the cloud is large. This result is agreement with the Jacob`s experimental results. (S.Y.)

  7. Evaluation of the performance characteristics of radon and radon-daughter concentration measurement devices under controlled environmental conditions

    International Nuclear Information System (INIS)

    Pearson, M.D.

    1989-04-01

    The Technical Measurements Center (TMC) conducted a study to expose 10 radon and 7 radon-daughter concentration measurement devices in the DOE/GJPO Radon/Radon-Daughter Environmental Chamber for a series of 24 controlled-environment tests. The tests evaluated the devices' response to temperature, relative humidity, dew point, condensation-nuclei concentration, radon-daughter/radon equilibrium ratio, and non-uniform radon and radon-daughter concentration. Devices were evaluated for linear response as a function of concentration. In addition to response to environmental parameters, the evaluation included determining the utility of the devices in providing reasonable assurance of compliance with the radon and radon-daughter concentration standards for DOE remedial action programs. This reasonable assurance criterion is based on a coefficient of variation of 25 percent for devices deployed for year-long measurements and a coefficient of variation of 18 percent for devices deployed for intermittent sampling. 39 refs., 65 figs., 33 tabs

  8. Radon and radon daughters' concentration in spring and wells waters from Presidente Prudente: preliminary results

    International Nuclear Information System (INIS)

    Osorio, Ana Maria Araya; Saenz, Carlos Alberto Tello; Pereira, Luiz Augusto Stuani

    2009-01-01

    This work presents the preliminary results about the concentration of radon and radon daughters in wells and springs water from Presidente Prudente. Six water samples were studied: three from well-water, two from springs water and one from potable water. For the determination of α-activity the samples were placed inside plastic containers where the CR-39 tracks detectors were outside the water. The track density of α-particles were measured by using optical microscopy. The results show that one sample from well-water presented higher concentration of radon and radon daughters than the other samples. (author)

  9. On the radiation dose to lung tissues from radon daughters

    International Nuclear Information System (INIS)

    Wise, K.N.

    1980-04-01

    The work of Harley and Pasternak on calculating dose conversion factors for radon daughters is re-examined. It is found that their estimates of the deposit of radon daughters on the lung airways are too low and the factor for converting from equilibrium activity of radon daughters on the airways to dose to basal cells is too high; these are re-calculated. However, it is shown that inter-subject variability of the depth of the basal cells leads to considerable uncertainty in the individual dose. Finally average dose conversion factors are re-calculated for atmospheres which may be charactersitic of underground mines; the dose conversion factors range from 8 mGy/WLM to 40 mGy/WLM as calculated from the Weibel lung model and from 3 mGy/WLM to 17 mGy/WLM as calculated from the Landahl lung model

  10. Radon daughter control in the Uravan Mineral Belt

    International Nuclear Information System (INIS)

    Swindle, R.W.

    1977-01-01

    The control of radon daughter products in mines of the Uravan Mineral Belt is strongly affected by the erratic nature of the ore deposits. Another problem is the frequent necessity of reactivating mine workings that have been inactive for many years. Ventilation holes and other airways are usually too small to provide adequate ventilation to satisfy current requirements, and they are often caved. The greatest change in ventilation systems in recent years has been the trend toward larger-diameter, drilled ventilation raises that provide more ventilation at considerably lower cost. The increase in raise size has aggrevated ground-support and ice-formation, difficulties, but these problems are being solved by lining the raises with shotcrete and grouting the water bearing horizons. Electronic air cleaners have been effectively used to remove radon daughter products from mine air for several years but their utility is limited by the rate of regrowth of the radon daughters after the air is cleaned. 5 figures

  11. Atmospheric radon daughters concentration inside and outside of cloud

    International Nuclear Information System (INIS)

    Nishikawa, Tsuguo; Okabe, Shigeru; Aoki, Masayoshi; Imamura, Takakazu; Iwata, Yoshitomo; Tamura, Yukihide; Tsuboguchi, Masayasu

    1987-01-01

    The measurements of the atmospheric radon daughters concentration in and out of the cloud were carried out on the top of the mountain, and in the upper air of the sea by using the airplane. The difference of the concentrations between inside and outside of the stratus measured on the top of the mountain was not clear. The atmospheric radon daughters concentration at the top of the mountain decreased when the amount of precipitation at that point was large. Concerning the cumulus investigated by using the airplane, the concentration in the cloud was a little higher than the concentration out of the cloud. Results of the measurements show that the cloud seems to be constructed of the various air masses whose radon daughters concentrations are different from each other even though it appears to be uniform. (author)

  12. Size distribution of radon daughter particles in uranium mine atmospheres

    International Nuclear Information System (INIS)

    George, A.C.; Hinchliffe, L.; Sladowski, R.

    1975-01-01

    The size distribution of radon daughters was measured in several uranium mines using four compact diffusion batteries and a round jet cascade impactor. Simultaneously, measurements were made of uncombined fractions of radon daughters, radon concentration, working level, and particle concentration. The size distributions found for radon daughters were log normal. The activity median diameters ranged from 0.09 μm to 0.3 μm with a mean value of 0.17 μm. Geometric standard deviations were in the range from 1.3 to 4 with a mean value of 2.7. Uncombined fractions expressed in accordance with the ICRP definition ranged from 0.004 to 0.16 with a mean value of 0.04. The radon daughter sizes in these mines are greater than the sizes assumed by various authors in calculating respiratory tract dose. The disparity may reflect the widening use of diesel-powered equipment in large uranium mines. (U.S.)

  13. Comparison of five-minute radon-daughter measurements with long-term radon and radon-daughter concentrations

    International Nuclear Information System (INIS)

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

    1983-01-01

    Five-minute air filter radon daughter measurements were made in 84 buildings in Edgemont, South Dakota, in which annual average radon daughter concentrations have been determined from six 100-hour Radon Progeny Integrating Sampling Unit (RPISU) measurements. Averaging radon concentrations were also determined in 50 of these buildings using Terradex Track Etch detectors. The standard deviation of the difference between the (natural) logarithms of the RPISU annual averages and the logarithms of the air filter measurements (SD-ln) was found to be 0.52. This SD-ln is considerably smaller than the SD-ln of 0.71 between the RPISU annual averages and the air filter measurements reported by ALARA at Grand Junction, Colorado; presumably because a considerable number of air filter measurements in Edgemont were disregarded because of short turnover times or high wind speeds. Using the SD-ln of 0.52 it can be calculated that there would only be a 5% probability in Edgemont that the RPISU annual average would be greater than 0.015 WL if the five-minute measurement were equal to 0.010 WL. This indicates that the procedure used in Edgemont of clearing buildings from remedial action if the five-minute measurement were less than 0.010 WL was reasonable. There was about a 28% probability that the RPISU annual average would be less than 0.015 WL if the five-minute measurement were 0.033 WL, indicating that the procedure of performing an engineering assessment if the average of two five-minute measurements was greater than 0.033 WL was also reasonable. Comparison indicates that the average of two RPISU measurements taken six months apart would provide a dependable estimate of the annual average

  14. Measurement of airborne concentrations of radon-220 daughter products by alpha-particle spectrometry

    International Nuclear Information System (INIS)

    Kerr, G.D.; Ryan, M.T.; Perdue, P.T.

    1978-01-01

    The decay of naturally occurring uranium-238 and thorium-232 produces radon-222 and radon-220 isotopes which can escape into the atmosphere. If these radon gases become concentrated in air, their daughter products may present an inhalation hazard to man. The airborne concentrations of radon-222 can usually be measured very accurately in the presence of normal airborne concentrations of radon-220 and its daughters. In contrast, the measurements of the airborne concentrations of radon-220 daughters are usually complicated by the presence of radon-222 and its daughters even at normally occurring airborne concentrations. The complications involved in these measurements can be overcome in most situations by using an alpha particle spectrometer to distinguish the activity of radon-222 daughters from that due to radon-220 daughters collected on a filter. A practical spectrometer for field measurements of alpha particle activity on a filter is discussed

  15. 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)

  16. Development and implementation of radon daughter measurement in Egypt

    International Nuclear Information System (INIS)

    Hussein, A.Z.; Mohamed, I.H.

    2005-01-01

    During the last decade, a programme was developed to study radon daughter risks and to carry out field and experimental measurements. The Egyptian Atomic Energy Authority lead the implementation of this programme in cooperation with the International Atomic Energy Agency through the coordination project EGY/9/020 and EGY/9/030. Several national authorities participated also in this study such as Nuclear Materials Corporation. This work involved the preparation and calibration of equipment, establishment of measuring techniques, survey in some cities and mines countrywide, and preparation of regulations for radiation safety of the workers who may be exposed to high levels of radon daughters. The study shows that there is no major environmental problem for the public due to exposure to radon daughter. Occupational problem may be probable in some underground mines with bad ventilation. Reported values for radon daughter levels in units of working level ranged from 0-0.26 in some buildings and ruins in the Egyptian cities and from 0-3 working level in underground phosphate and uranium mine in the Egyptian Eastern Desert

  17. A law of removing radon by ventilation and air requirement calculation for eliminating radon daughters in uranium mines

    International Nuclear Information System (INIS)

    Wu Gang

    1988-06-01

    In accordance with testing data of removing radon and its daughters by ventilation from shrinkage and filling stopes of uranium mines, a law of removing radon by ventilation from the stopes is analyzed and summed. According to the decay law of radon and its daughters, an accumulation equation of potential alpha energy from radon daughters is presented with hyperbolic regression equation. the calculating formulae of ventilation flow are derived from the accumulation equation for eliminating radon daughters in inlet flow with or without contamination. It has been proved that the amount of ventilation air calcuated could meet the requirements of radiation safety rationally and economically

  18. Decommissioning/closeout of Malargue site: measurement of radon daughter

    International Nuclear Information System (INIS)

    Avila Cadena, Guadalberto

    2000-01-01

    In Malargue complex there are about 700,000 mt of uranium tailings disposed off during 32 years of operation of the Malargue facility. The objective of the Malargue Site is to undertake the necessary actions to execute remediation programs. A summary of measurements of concentrations of radon daughter taken in different buildings of the city and in the field shows the influence of radon source. The results obtain for concentrations of radon daughter indicate that they do not differ significantly between each others. The environmental remediation of uranium mill tailings at Malargue Site is a requirement of Nuclear Regulatory Authority (NRA) and of the Mendoza province and a commitment to reduce the doses as low as reasonably achievable, social and economic factors being taken into account (ALARA concept). (author)

  19. Radon risk in residential buildings

    International Nuclear Information System (INIS)

    Niewiadomski, T.

    1996-01-01

    The author discusses the risk related to the inhalation of radon decay products. This products are the cause of almost the half of the doses absorbed by the people. The concentration of radon in buildings is much higher than in the open areas and its country average in Poland is 50 Bq/m 3 . It is difficult to predict the concentration of radon in the building without measurement. Author concludes that there are technical means to decrease radon concentration in buildings

  20. Occupational studies of radon daughters and lung cancer

    International Nuclear Information System (INIS)

    Hornung, R.W.; Ballew, M.A.

    1988-01-01

    The relationship between exposure to radon daughters and lung cancer mortality has been established. The purpose of this paper is to review some of the major studies of the health effects due to exposure to the decay products of radon gas and to discuss their potential implications with regard to risk associated with indoor radon. There has been much recent interest in the health hazards associated with radon largely motivated by the discovery of high levels of this radioactive gas in the Reading Prong (a geological area in Pennsylvania and New Jersey) and subsequently throughout the United States. Although at least three studies in the U.S. have been initiated to better estimate the lung cancer risks from low level indoor radon exposure, the results will not be known for several years. Consequently, present knowledge concerning such risks is almost entirely derived from studies of underground exposure to miners. Those studies effectively exclude women and children; therefore, assumptions must be made with regard to risk to a large segment of the population. Before discussing current health studies of radon daughter exposure, some background information is presented

  1. Multivariate signal processing in measurements of radon and radon daughters in air

    International Nuclear Information System (INIS)

    Urbanski, P.; Machaj, B.

    2000-01-01

    Extensive measurements of radon and radon daughters concentration gauge in a radon chamber were carried out. Count rate 'spectra' against time at the output of radiation detectors were measured and registered. The count rate spectra were then processed employing Principal Component Regression (PCR). A root mean square error of the count rate was estimated. It was found that PCR processing removes a great part of count rate random fluctuations originating from the radiation statistics that results in a decrease of count rate random error. The root mean square error of count rate in a radon daughter monitor is about 3 times lower, which is equivalent to the error of the gauge with a 9 times higher air flow rate if no PCR processing is used. In case of the radon concentration gauge the increase of sensitivity is even higher and amounts to 5 times. (author)

  2. 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

  3. Size distribution of radon daughter particles in uranium mine atmospheres

    International Nuclear Information System (INIS)

    George, A.C.; Hinchliffe, L.; Sladowski, R.

    1977-07-01

    An investigation of the particle size distribution and other properties of radon daughters in uranium mines was reported earlier but only summaries of the data were presented. This report consists mainly of tables of detailed measurements that were omitted in the original article. The tabulated data include the size distributions, uncombined fractions and ratios of radon daughters as well as the working levels, radon concentrations, condensation nuclei concentrations, temperature, and relative humidity. The measurements were made in 27 locations in four large underground mines in New Mexico during typical mining operations. The size distributions of the radon daughters were log normal. The activity median diameters ranged from 0.09 μm to 0.3 μm with a mean of 0.17 μm. Geometric standard deviations were from 1.3 to 4 with a mean of 2.7. Uncombined fractions expressed in accordance with the ICRP definition ranged from 0.004 to 0.16 with a mean of 0.04

  4. Experimental pulmonary carcinogenesis by radon and its daughters

    International Nuclear Information System (INIS)

    Sato, Fumiaki

    1989-01-01

    Information on experimental pulmonary carcinogenesis by radon and its daughters has come mostly from experiments carried out in France and United States of America. In rats a dose response relation was estimated to be linear with dose at low dose region. Studies of rats exposed daily to radon and radon daughters indicated that the frequency of pulmonary cancer at total exposure greater than 3000 WLM was greater when the exposure rates were low. At low total exposures the dose-rate effect was less apparent. Cigarette smoke increased the pulmonary cancer in rats but decreased in dogs. The decrease may be due to a decrease of absorbed doses with increased secretion of mucus and to an enhancement of mucociliary clearance. After inhalation of 222 Ru at equilibrium with radon daughters, rats were inoculated intrapleurally with asbestos fibres or glass fibres. The additive co-carcinogenic effects of this type of insult were demonstrated by the increased incidence of malignant thoracic tumours. As for species differences, dogs and hamsters are relatively resistant to cancer induction and rats are sensitive. While bronchogenic carcinomas are the most frequently observed radiation-induced pulmonary cancer in humans, bronchioloalveolar carcinomas are the most frequent type in most animal species. (author)

  5. Comparing summer and winter indoor radon and radon daughters activity in Campinas, Brazil

    International Nuclear Information System (INIS)

    Guedes, O.S.; Hadler, N.J.C.; Iunes, P.J.; Neman, R.S.; Souza, W.F.; Tello, S.C.A.; Paulo, S.R.

    2002-01-01

    We developed a technique - based on alpha particle track detection using CR-39 - where the activity originated from indoor radon can be potentially separated into three fraction: (i) radon in the air, (ii) radon daughters (RD), 218 Po and 214 Po, in the air and (iii) RD plated-out on the detector surface during exposure. In this work only a partial separation was carried out, then our results are limited to radon plus RD in the air and RD attached to detector surface. These activities can be separated if size and gray level of the round tracks are measured using an automatic optical microscopy system.Our group carried out an indoor radon and radon daughters (RD) survey in Campinas made up by a summer (November, 96 to May, 97) and a winter (May, 97 to November, 97) exposure, where the detectors were placed in the same rooms of the same dwellings (approximately 100) in both cases. Comparing winter and summer alpha activity for the detectors analyzed up to now, approximately 45 dwellings, we observed that: i) it seems that the source of radon is the material (brick and concrete mainly) making up walls, floor and ceiling of the dwellings, ii) there is no clear relationship between intensity of aeration and the activities measured in this work, and iii) the average ratio between winter and summer activity in the air (radon plus RD) is approximately equal to similar ratios observed in other countries, but for radon only. (author)

  6. Some measurements of radon and its daughters in houses

    International Nuclear Information System (INIS)

    Rundo, J.; Markun, F.; May, H.A.; Plondke, N.J.; Keefe, D.J.

    1979-01-01

    The bare soil in the unpaved crawl space of a house is the source of unusually high levels (greater than or equal to 185 Bq m -3 ) of radon in the air of some houses (46% of those investigated), although the radium content of the soil is normal (approx. 40 Bq kg -1 ). High concentrations can also be found in the air in the basement sump. Measurements made with an Environmental Working Level Monitor in two houses showed that the average annual concentration of radon daughters may be in the region of 0.01 WL

  7. Model dosimetric for Radon and Daughters

    International Nuclear Information System (INIS)

    Puerta, J.A.; Cardenas, H.F.

    1998-01-01

    You elaborates a model dosimetric for radon and their products of decline of short half life starting from the new model of the breathing tract of the publication 66 of the ICRP and the use of the systemic models proposed in the publication 67, 68 and 69 of the same commission. The correlated used methodology the incorporation of these radionuclides with the activity in organs and you excrete, considering the difference of metabolic behavior of the products of decline and of their predecessor

  8. Third workshop on radon and radon daughters in urban communities associated with uranium mining and processing. Pt. 1

    International Nuclear Information System (INIS)

    1980-01-01

    This third meeting of Atomic Energy Control Board staff, contractors, federal and provincial government representatives, and delegates from outside Canada was held to discuss progress in reducing concentrations of radon and radon daughters in houses. Speakers talked about successful and unsuccessful remedial measures, methods of measuring and monitoring thoron and radon in houses, and indoor radon concentrations in Canada, Britain and Sweden

  9. 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)

  10. Radon: Residential attitudes toward the risk

    International Nuclear Information System (INIS)

    Fort, R.; Hinman, G.; Rosenman, R.; Wandschneider, P.

    1990-01-01

    Veradale, Washington (east of Spokane) is a region of high residential radon concentrations. Three hundred eighty residents of Veradale recently responded to a mail survey designed to elicit (1) their knowledge of and attitudes toward the risks of radon in their homes, (2) the actions they have taken or intend to take to identify and reduce those risks, and (3) policy preferences toward radon. Results reveal that these residents know that they live in an area with high radon levels, that radon causes lung cancer, and that radon will affect their health. However only 11% of respondents have had their homes tested for radon. This especially is puzzling because a large number of respondents claimed that (1) radon was important in home buying decisions, (2) they would test their own homes, (3) they would take action if such tests revealed problems, and (4) their willingness to pay for tests and improvements was well within the current costs of these actions. It remains a mystery why testing is at such a low level. Three other results are of note. First, subsidies for radon tests and home improvements may be having the unintended consequences of unneeded improvements and (potentially) moves without improvements. Second, individuals want radon testing required and results made known during home purchase decisions. Third, at present, weatherization programs that concentrate radon are acceptable to individuals. Of course, the future may hold different results. Administrators of weatherization programs, who are trusted by respondents according to this survey, would do well to institute weatherization programs with reduced radon concentrations in mind

  11. 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

  12. Investigations of radon and radon daughters in surficial aquifers of florida

    International Nuclear Information System (INIS)

    1991-05-01

    The principal purpose of the investigation was to test the hypothesis that radon soil flux, considered the principal source of indoor radon contamination, has an underlying relationship to the radon content of associated shallow groundwaters. The working hypothesis was that radon build-up in both soil and shallow groundwater is basically a consequence of the same factor, radon emanation from soil grains and the solid surfaces of the aquifers. Groundwater may be advantageous as an indicator of radon potential. Another object of the project was to investigate temporal and spatial trends of radon daughter products in shallow aquifers. After analyzing all of the radon soil, flux, and groundwater measurements made over the two-year study period, it is clear that while there is no direct relationship between either radon soil concentration or flux and groundwater radon. Measurements in wells where polonium is present at very high concentrations have shown that 210Po is largely unsupported by its radioactive predecessor, and that polonium is considerably more variable, in both space and time than other parameters measured in the same wells, including radon

  13. Influence of various room parameters upon radon daughter equilibrium indoors

    International Nuclear Information System (INIS)

    Islam, G.S.; Mazumdar, S.C.; Ashraf, M.A.

    1995-06-01

    The parameters such as ventilation rate, attachment rate to aerosols and deposition processes, which influence the radon daughter equilibrium indoors, are discussed and the validity of the theoretical model checked by experiments. In agreement with the model calculations, the experimental data show, that the equilibrium factor F in rooms is mainly influenced by the rate of attachment to aerosols and the plateout of radon daughters. The equilibrium factor varies between 0.3 and 0.4 at an attachment rate of 300 h -1 . The influence of ventilation upon the free fraction of RaA( 218 Pp)-atoms is also investigated. This is in good agreement with the results of the measurements carried out in different types of rooms at the University Campus of Rajshahi. (author). 20 refs, 3 figs, 3 tabs

  14. Electronic instrument for radon daughter dosimetry. Report of investigations

    International Nuclear Information System (INIS)

    Durkin, J.

    1977-01-01

    Due to the daily exposures of uranium mining personnel to 222Rn daughters, a device is needed which will continually monitor the individual's exposure. Such a device has been built and tested and is known as the Radon Daughter Dosimeter. This is an electronic instrument using a solid-state detector and circuitry. The system permits the evaluation of cumulative exposures to airborne radon progeny, expressed in units of Working Level Hours (WL-HRS). The instrument is a personal device worn by the individual throughout the working shift. Since the instrument is in close proximity to the miner and measures continual exposure, it provides an accurate account of total cumulative exposure, thus avoiding the errors caused by the present technique of spot checking of the environment

  15. Develop generic equations to determine radon daughters concentrations in air

    International Nuclear Information System (INIS)

    Shweikani, R.; Jerby, B.

    2011-06-01

    Measurements of radon daughter concentrations in air are very important to determine the human dose from background radiation. Therefore, many studies tried to find measurements methods depending on many specific parameters such as measurement time, air pumping period and sample volume. In this study a general equations to determine radon daughter's concentrations in air was found using direct samples. The Equations results were closed to the results obtained from other well known methods. Many measurements with different places and various conditions were performed; the results showed that the new equations are able to be used with an error less than 10%, The relative error can be reduced by increasing the pumping rate or measuring high concentration cases.(author)

  16. Methodology and monitoring of radon, thoron and their daughters

    International Nuclear Information System (INIS)

    Townsend, M.G.

    1984-02-01

    Methods are described for monitoring radon and thoron gases and their daughter products in occupational and non-occupational environments. Grab-sampling, continuous monitoring, integrated measurements and personal dosimetry are discussed. Errors in different measurement methods are compared. Calibration aspects of measurement techniques are described and procedures for interlaboratory calibration are suggested. An account of unattached fraction and plateout of radon daughters is included. Sampling strategies for occupational and non-occupational environments are discussed and a table of regulations and recommendations for monitoring radiation in countries of the OECD is provided. Radiation protection training requirements are identified. Where sufficient information and consensus of opinion exist, guidelines on apparatus, methods and procedures for monitoring are developed

  17. Development of diffusion-based radon daughter dosimeters

    International Nuclear Information System (INIS)

    Phillips, C.R.; Khan, A.; Leung, H.

    1983-07-01

    The objective of this work is to investigate the possible application of the mechanisms of thermophoresis and electrostatic collection via electrets to the collection of radon daughters with reference to personal alpha dosimeters for use in uranium mines. The potential advantage accruing from adoption of either one of these collection mechanisms is that collection is passive and does not depend upon the use of a pump (active), and is, therefore, intrinsically much more reliable

  18. Radon and radon-daughter concentrations in air in the vicinity of the Anaconda Uranium Mill

    Energy Technology Data Exchange (ETDEWEB)

    Momeni, M H; Lindstrom, J B; Dungey, C E; Kisieleski, W E

    1979-11-01

    Radon concentration, working level, and meteorological variables were measured continuously from June 1977 through June 1978 at three stations in the vicinity of the Anaconda Uranium Mill with measurements integrated to hourly intervals. Both radon and daughters show strong variations associated with low wind velocities and stable atmospheric conditions, and diurnal variations associated with thermal inversions. Average radon concentration shows seasonal dependence with highest concentrations observed during fall and winter. Comparison of radon concentrations and working levels between three stations shows strong dependence on wind direction and velocity. Radon concentrations and working-level distributions for each month and each station were analyzed. The average maximum, minimum, and modal concentration and working levels were estimated with observed frequencies. The highest concentration is 11,000 pCi/m/sup 3/ on the tailings. Working-level variations parallel radon variations but lag by less than one hour. The highest working levels were observed at night when conditions of higher secular radioactive equilibrium for radon daughters exist. Background radon concentration was measured at two stations, each located about 25 km from the mill, and the average is 408 pCi/m/sup 3/. Average working-level background is 3.6 x 10/sup -3/.

  19. Radon and radon-daughter concentrations in air in the vicinity of the Anaconda Uranium Mill

    International Nuclear Information System (INIS)

    Momeni, M.H.; Lindstrom, J.B.; Dungey, C.E.; Kisieleski, W.E.

    1979-11-01

    Radon concentration, working level, and meteorological variables were measured continuously from June 1977 through June 1978 at three stations in the vicinity of the Anaconda Uranium Mill with measurements integrated to hourly intervals. Both radon and daughters show strong variations associated with low wind velocities and stable atmospheric conditions, and diurnal variations associated with thermal inversions. Average radon concentration shows seasonal dependence with highest concentrations observed during fall and winter. Comparison of radon concentrations and working levels between three stations shows strong dependence on wind direction and velocity. Radon concentrations and working-level distributions for each month and each station were analyzed. The average maximum, minimum, and modal concentration and working levels were estimated with observed frequencies. The highest concentration is 11,000 pCi/m 3 on the tailings. Working-level variations parallel radon variations but lag by less than one hour. The highest working levels were observed at night when conditions of higher secular radioactive equilibrium for radon daughters exist. Background radon concentration was measured at two stations, each located about 25 km from the mill, and the average is 408 pCi/m 3 . Average working-level background is 3.6 x 10 -3

  20. The use of mechanical ventilation with heat recovery for controlling radon and radon-daughter concentrations

    International Nuclear Information System (INIS)

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

    1980-01-01

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

  1. Evaluation and control of radon daughter hazards in uranium mines

    International Nuclear Information System (INIS)

    Holaday, D.A.

    1974-11-01

    This monograph discusses primarily those health hazards to uranium miners which are produced by exposure to ionizing radiation. Emphasis is placed on the areas of evaluation of exposures to the radioactive gas radon-222 and its short-lived transformation products, and methods of controlling such exposures. A limited discussion of the biological effects of radon and radon daughters is undertaken, and some procedures are given for evaluating hazards created by other common contaminants of mine atmospheres. A large amount of information exists on these topics, some of which is unpublished or is not readily available. While efforts were made to obtain data from all sources, undoubtedly some valuable work was overlooked. The monograph is an endeavor to assemble pertinent information and make it available to those who are concerned with producing uranium at minimal risks. Where they were available, a variety of procedures for evaluating hazards are given, and examples of systems for controlling hazards are included. 154 references

  2. Reducing radon daughter background in alpha continuous air monitors

    International Nuclear Information System (INIS)

    Rodgers, J.C.; McFarland, A.R.

    1991-01-01

    Alpha continuous air monitors are instruments designed to sample aerosols which may contain alpha-emitting radionuclides and, in near-real time, to monitor the sample for alpha emissions. This process is subject to interference from radon decay products. The usual method for overcoming this interference is by signal processing or data processing in such a manner as to accurately subtract a portion of the background from the transuranic count. An innovative alternative approach has been jointly developed in a collaboration between Los Alamos National Laboratory and Texas A ampersand M University. The concept is to attempt to physically remove a portion of the interfering radon daughters from the incoming sample by a diffusion screen before the sample is collected. The results of laboratory tests indicate that a very high removal efficiency for unattached radon progeny can be obtained without excessive loss of efficiency for collection of the contaminant aerosols of concern. 15 refs., 4 figs., 1 tab

  3. Studies on deposition of radon daughters on glass surface

    International Nuclear Information System (INIS)

    Loerinc, M.; Feher, I.; Palfalvi, J.

    1998-01-01

    In a certain village in Northern Hungary, in some houses the radon concentration was found to be in the order of kBq.m -3 . In an attempt to decide whether an earthquake or the near-by mining activity is to blame, past radon concentration was studied making use of radon daughters embedded in the surface layer of glass sheets. In the investigation several conclusions were reached: drastic changes in Rn concentration could be excluded, ie., the high Rn concentration existed over the last 50 years; the continuing deposition of dirt on the glass surface and the occasional cleaning had no significant effect; the effect of corrosion processes at the glass surface should be further investigated. (A.K.)

  4. Metrology and monitoring of radon, thoron and their daughter products

    International Nuclear Information System (INIS)

    1985-01-01

    The principles of measurement and monitoring are described as applied to radon- and thoron gases and their daughter products in occupational and non-occupational environments. Various methods of measurement, such as grab-sampling, continuous monitoring, integrated measurements and personal dosimetry are discussed. Uncertainties in different measurement methods are compared. An account of unattached fraction and plateout of radon daughters is included. General principles and guidelines for monitoring are presented for the purposes of practical radiation protection as well as research applications. Calibration aspects of measurement instruments are described and procedures for interlaboratory calibration are suggested. Sampling strategies for occupational and non-occupational environments are discussed and radiation protection training requirements are identified. Where sufficient information and consensus exist, guidelines on apparatus, methods and procedures for monitoring are provided. A summary of regulations in force or being developed and recommendations for monitoring radiation exposure to radon and its decay products in countries of the OECD is provided, together with cost estimates for national indoor radon surveys

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

    International Nuclear Information System (INIS)

    Evans, H.H.

    1997-01-01

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

  6. A computer method for simulating the decay of radon daughters

    International Nuclear Information System (INIS)

    Hartley, B.M.

    1988-01-01

    The analytical equations representing the decay of a series of radioactive atoms through a number of daughter products are well known. These equations are for an idealized case in which the expectation value of the number of atoms which decay in a certain time can be represented by a smooth curve. The real curve of the total number of disintegrations from a radioactive species consists of a series of Heaviside step functions, with the steps occurring at the time of the disintegration. The disintegration of radioactive atoms is said to be random but this random behaviour is such that a single species forms an ensemble of which the times of disintegration give a geometric distribution. Numbers which have a geometric distribution can be generated by computer and can be used to simulate the decay of one or more radioactive species. A computer method is described for simulating such decay of radioactive atoms and this method is applied specifically to the decay of the short half life daughters of radon 222 and the emission of alpha particles from polonium 218 and polonium 214. Repeating the simulation of the decay a number of times provides a method for investigating the statistical uncertainty inherent in methods for measurement of exposure to radon daughters. This statistical uncertainty is difficult to investigate analytically since the time of decay of an atom of polonium 218 is not independent of the time of decay of subsequent polonium 214. The method is currently being used to investigate the statistical uncertainties of a number of commonly used methods for the counting of alpha particles from radon daughters and the calculations of exposure

  7. Tracing and dealing with dwellings with high radon and radon daughter concentrations

    International Nuclear Information System (INIS)

    Ehdwall, Hans

    1980-01-01

    In the late 1970s it was found that a number of buildings in Sweden, primarily those made from alum shale-based concretes, had elevated radon and radon daughter levels. A special commission investigated the problem and established provisional limiting values for radon daughter exposures, gamma radiation from the ground, and the concentrations of radioactive materials in building materials. With regard to gamma radiation from the ground the commission proposed that no building be built in an area where outside gamma radiation exceeds 100 μR/h. For building materials a gamma index (mγ) and a radium index (mRa) are suggested: mγ = Csub(K)/10000 + Csub(Ra)/1000 + Csub(Th)/700; mRa = Csub(Ra)/200 (Csub(K), Csub(Ra) and Csub(Th) are the concentrations of potassium, radium and thorium respectively). The proposed limiting values are such that the gamma index and the radium index be less than 1. It is also suggested that action should be taken to reduce radon levels in buildings with radon daughter concentrations of 0.27 WL within two years and 0.10 WL within 5 years

  8. The attachment of radon daughters to submicron aerosol particles

    International Nuclear Information System (INIS)

    Grenier, M.G.; Bigu, J.

    1984-04-01

    A study of the effects of aerosol concentration, aerosol size distribution and relative humidity on the Working Level and the radon daughter concentration was conducted in a 3000 L radon environmental chamber. Typical values of the aerosol concentration varied in the 1 x 10 3 particles/cm 3 to 4.5 x 10 5 particles/cm 3 range. Various size distributions of aerosols that have mean diffusional aerodynamic diameters of .025 μm, .045 μm and .090 μm were tested. A good correlation was found between the Working Level and the aerosol concentration as well as the relative humidity. Most of the activity seems to be associated with particles of diameter between .05 μm and .2 μm. The results presented here are in agreement with work done by other investigators in the health physics field

  9. Dosimetry of radon and its daughters by two SSNT detectors

    International Nuclear Information System (INIS)

    Faj, Z.; Planinic, J.

    1991-01-01

    Disintegration, ventilation and deposition (plateout effect) were considered as removal processes for radon and its daughters in the air and their concentration equations were used in deriving a relationship between the equilibrium factor (F) and track densities of the bare SSNT detector (D) and the filtered one (D 0 ). Using the calibrated sensitivity coefficient of the LR-115 detector, k=2.64x10 -3 m, and the measured average track densities (D,D 0 ) in a single house living room in Osijek during the year 1989, the radon concentration c 0 =40.15 Bq.m -3 , equilibrium factor F=0.46 and effective dose equivalent H E =1.48 mSv.y -1 were obtained. (author)

  10. 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

  11. Ventilation cost impact of reduced radon-daughter working levels

    International Nuclear Information System (INIS)

    Bates, R.C.

    1981-01-01

    Published information on costs of radon-daughter control in uranium mines was analyzed to develop estimates of the cost per ton for any level of radiation exposure control. All data were converted to 1967 cost of living index to provide a common analysis base. Results of the analysis show that the cost per ton increases exponentially as the radiation level is lowered. A linear relationship with the cost of living index is assumed, and equations and graphs are provided to estimate control cost per ton for any exposure control level and cost of living index

  12. Bio-mathematical models for radon daughters inhalation. The ModeLung software

    International Nuclear Information System (INIS)

    Tomulescu, Vlad C.; Rusu, Mircea

    2002-01-01

    Radon and its decay daughters are the most important sources for natural irradiation of population. ModeLung software is based on the human respiratory tract compartment model and is computing radiation doses on several internal organs and tissues for subjects inhaling radon daughters attached to aerosols. Radiation doses are presented for several subjects performing different types of activity under specific environmental conditions. (authors)

  13. Studies on the migration rule and mechanism of radon and its daughters

    International Nuclear Information System (INIS)

    Jia Wenyi; Fang Fang; Zhou Rongsheng; Ma Yingjie; Qiu Yuande; Hou Xinsheng; Wu Yunping; Zu Xiulan; Wang Xiaoqin

    2000-01-01

    By using very precise, highly sensitive, static accumulated, easily repeated CD-1 α-cup, the migration rule and mechanism of radon and its daughters was studied. Significant results were obtained: (1) Under laboratory conditions, the vertical component of migration of radon and its daughters was much greater than the horizontal component, the former was over 90% and the latter was less than 10%. (2) Despite the very big specific gravity of radon and its daughters, the descending component of migration was less than 45%, while the ascending component was more than 45%. (3) After α-particles (emitted from radon and its daughters) being slowed down. 4 He combined with the radon and its daughters to form clusters. When the density of the cluster was less than that of the air, the self-ascending would occur

  14. 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)

  15. Biological effects of daily inhalation of radon and its short-lived daughters in experimental animals

    International Nuclear Information System (INIS)

    Palmer, R.F.; Stuart, B.O.; Filipy, R.E.

    1973-01-01

    Syrian golden hamsters, C57BL mice, and specific-pathogen-free rats were exposed simultaneously in groups of 16 animals each for 90 hours per week to aerosols consisting of radon plus 3000--6000 Working Levels of radon-daughters with and without 18 mg/m 3 carnotite uranium ore dust. Condensation nuclei concentrations ranged from 2000--4000 per ml and from 90,000--120,000 per ml in the chamber without and with uranium ore dust, respectively. At 4 months of exposure only one of the rodents remained alive. Histopathology of radon-daughter exposed mice includes acute interstitial pneumonitis, severe pulmonary congestion, and supperative rhinitis; mice inhaling radon-daughters with ore showed these lesions plus macrophage proliferation, alveolar septal cell hyperplasia, and bronchial epithelial hyperplasia. Hamsters inhaling radon-daughters showed proliferating lesions characterized by alveolar septal thickening, bronchiolar epithelial hyperplasia, septal fibrosis, and occasionally adenomatoid metaplasia and squamous metaplasia. Hamsters inhaling radon-daughters with ore dust showed similar effects plus granulomatous response and intense septal fibrosis. Rats inhaling radon-daughters showed lesions similar to those of hamsters but more focalized with classic radiation pneumonitis; rats exposed to radon-daughters with ore showed similar lesions, with greater consolidation and pneumoconiosis. These findings will be discussed in relation to pulmonary pathology in uranium miners

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

    International Nuclear Information System (INIS)

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

    1986-01-01

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

  17. Radon and radon daughters indoors, problems in the determination of the annual average

    International Nuclear Information System (INIS)

    Swedjemark, G.A.

    1984-01-01

    The annual average of the concentration of radon and radon daughters in indoor air is required both in studies such as determining the collective dose to a population and at comparing with limits. Measurements are often carried out during a time period shorter than a year for practical reasons. Methods for estimating the uncertainties due to temporal variations in an annual average calculated from measurements carried out during various lengths of the sampling periods. These methods have been applied to the results from long-term measurements of radon-222 in a few houses. The possibilities to use correction factors in order to get a more adequate annual average have also been studied and some examples have been given. (orig.)

  18. 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

  19. Mapping of residential radon in the world

    International Nuclear Information System (INIS)

    Zielinskia, Jan M.; Chambers, Douglas B.

    2008-01-01

    European countries (out of 46) with data. Using data from the database, we have created a map of national levels of residential radon around the world. In addition to static map, we have also implemented a preliminary web version and Google Earth version of the map. (author)

  20. Assessment of radon-daughter deposition in the respiratory tract

    International Nuclear Information System (INIS)

    Oberstedt, S.; Vanmarcke, H.

    1996-01-01

    Since some decades it is known, that most of the radiation dose to the lung is due to the inhalation of the short-lived decay products of 222 Rn. Their deposition in the respiratory tract strongly depends on the attachment rate to aerosol-particles present in the indoor air and their plate-out rate to the surfaces, instead of measuring the activity size distribution of the airborne decay products, knowledge on the respiratory tract retention has been incorporated in the design of a measurement system, called bronchial dosemeter, to assess the lung dose directly. The simulation of the deposition characteristics of the short-lived radon daughters in the nasal cavity and the bronchial tree is based on the comparison of the model of the respiratory tract with results from screen penetration theory. A bronchial dosemeter consisting of three sampling heads has been built and calibrated. Additionally, an outline of future activities will be given. (author)

  1. 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

  2. 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

  3. 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

  4. Measurement of simulated lung deposition of radon daughters

    International Nuclear Information System (INIS)

    Jonassen, N.; Jensen, B.

    1992-01-01

    A measurement system for the lung deposition of radon daughters based on respiratory models was suggested by Hopke et al. By choosing suitable mesh size and flow velocities it is possible to design a multiple-wire screen sampler simulating deposition in the respiratory tract of aerosols over the size range 0.5-1000 nm. This paper describes a preliminary investigation where simulated deposition in the nasal tract and in the bronchii (for mouth breathing as well as nasal breathing) is determined. The measurements were performed in atmospheres where the normalised exposure rate (equilibrium factor) was varied by changing the aerosol loading of the air as well as by enhanced electrostatic plateout. The general results of the measurements are that the energy deposited in the nose with nasal breathing and in the bronchii with mouth breathing varies as the calculated dose while the energy deposited in the bronchii with nasal breathing follows the exposure. It is also demonstrated that the energy deposited for a fixed value of the radon concentration may vary by a factor of 2-7 depending on the treatment of the air. (author)

  5. Problems of the inclusion of workplaces with enhanced radon and radon daughter concentrations into occupational radiation protection control

    International Nuclear Information System (INIS)

    Przyborowski, S.

    1993-01-01

    New international recommendations (ICRP-60) on inclusion of workplaces with enhanced radon and radon daughter concentrations into occupational control are expected. Based on present regulations in Germany the problems of their implementation into radiation protection practice will be discussed. For underground workplaces and workplaces in radon spas and waterworks problems may be exist in particular points, whereas inclusion of workplaces in buildings seems to be problematicly in general. (orig./HP) [de

  6. Some aspects of radon and its daughter-products in man and his environment

    International Nuclear Information System (INIS)

    Rundo, J.; Markun, F.; Plondke, N.J.; Sha, J.Y.

    1981-01-01

    A major but short-lived postprandial increase in the exhalation rate of radon by persons containing no radium was observed. The concentrations of radon and its short-lived daughter-products in houses was unusually high (> 5 to 10 pCi l - 1 , > 185 to 370 Bq m - 3 ) in some houses with unpaved crawl spaces, and with concrete basements. External counting of radon daughter-products in the residents of one of the radon-contaminated houses indicated that there may be interference with the assay of plutonium in the lungs of persons who live in those houses

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

    International Nuclear Information System (INIS)

    Wang, H.; Essling, M.A.; Toohey, R.E.; Rundo, J.

    1982-01-01

    The deposition rates of radon daughters on indoor surfaces have been measured by exposing the window of a proportional counter to the air of a house with high concentrations of radon and its daughters. Deposition velocities for unattached 218 Po (RaA) and 214 Pb (RaB) of approximately 4 mm sec - 1 were obtained by dividing the deposition rates by the concentrations of unattached daughters in the air. These results agree with those obtained by other workers but are dependent on the assumptions made about the fractions of the daughters which are attached to the atmospheric aerosol

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

    International Nuclear Information System (INIS)

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

    1989-01-01

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

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

    International Nuclear Information System (INIS)

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

    1996-01-01

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

  10. The determination of a continuous radon daughter equilibrium factor in an operating uranium mine

    International Nuclear Information System (INIS)

    Billingsley, D.

    1992-01-01

    Radon daughter exposures to workers at the Olympic Dam Operations copper and uranium mine are calculated from a series of grab samples obtained from various work locations around the mine. Currently under consideration is the introduction of personal passive radon dosimeters to determine the workers' radon daughter exposures. The study reported in this paper involved the determination of long-term equilibrium factors using real-time monitoring of radon and radon daughters. Consequently, variation in equilibrium factor for different tasks can be identified. In practice, the equilibrium factor varies with location and task; however, a conservative over-estimate of 0.28 can be confidently applied to all tasks. The error due to over-estimation remains minimal for all workers. This real-time monitoring method will reduce potential errors in dose assessment compared with the grab sampling technique. 5 refs., 1 tab., 4 figs

  11. Internal causes of radon and its daughters upward migration and cluster phenomenon

    International Nuclear Information System (INIS)

    Jia Wenyi; Fang Fang; Zhou Rongsheng; Ma Yingjie; Qiu Yuande; Hou Xinsheng; Wu Yunping; Zu Xiulan; Wang Xiaoqin

    1999-01-01

    Radon and its daughters have a very big specific gravity. But under laboratory conditions, they have the ability to migrate upward. The phenomenon can't be interpreted by an external cause but by an internal cause. The mechanism is that radon and most of its daughters and parents are decaying bodies able to radiate α-particles. After deceleration, 4He can combine with radon and its daughters and parents to form clusters. When the buoyancy of air is greater than the gravity of the clusters, self-ascending occurs. Accordingly, the distance that Rn covered during 3.825 days (Rn half-life) should not be regarded as Rn and its daughters migrating distance, but should be calculated according to all effects. That clusters can be formed by 4He, Rn and its daughters are valuable to study because of the similarity between Rn and heavy metal particles

  12. Working towards residential Radon survey in South America

    International Nuclear Information System (INIS)

    Zielinski, Jan M.; University of Ottawa, ON; Canoba, Analia C.; Shilnikova, Natalia S.; Veiga, Lene H. S.

    2008-01-01

    Information about residential radon levels in low and middle income countries is very sparse. In response to the World Health Organization initiative in the International Radon Project, we propose a research project that will address this knowledge gap in South America by conducting a residential radon survey. Following initial in vitro and in vivo studies of radon and studies of uranium miners exposed to radon, over twenty large case-control studies of lung cancer risk from exposure to residential radon have been completed worldwide by year 2004. Recently pooled data from these individual studies have been analyzed. These collaborative analyses of the indoor studies in Europe, North America, and China provide strong direct evidence that radon is causing a substantial number of lung cancers in the general population. To reduce radon lung cancer risk, national authorities must have methods and tools based on solid scientific evidence to develop sound public health policies. We propose to conduct a survey in ten South American countries using the distribution and analysis of passive alpha tracking detectors in houses selected at random in pre-selected cities in each participating country. We also present an approach to estimate the cost of carrying out such a survey and the radon laboratory infrastructure needed. The results of the proposed survey will allow to conduct assessment of the exposure to residential radon in the populations of South American countries and to assess the health impact of this exposure. The results of the project will also help national health authorities in developing national residential radon action levels and regulations, as well as provide public health guidance for radon awareness and mitigation. (author)

  13. Residential radon in Finland: sources, variation, modelling and dose comparisons

    Energy Technology Data Exchange (ETDEWEB)

    Arvela, H

    1995-09-01

    The study deals with sources of indoor radon in Finland, seasonal variations in radon concentration, the effect of house construction and ventilation and also with the radiation dose from indoor radon and terrestrial gamma radiation. The results are based on radon measurements in approximately 4000 dwellings and on air exchange measurements in 250 dwellings as well as on model calculations. The results confirm that convective soil air flow is by far the most important source of indoor radon in Finnish low-rise residential housing. (97 refs., 61 figs., 30 tabs.).

  14. Residential radon in Finland: sources, variation, modelling and dose comparisons

    International Nuclear Information System (INIS)

    Arvela, H.

    1995-09-01

    The study deals with sources of indoor radon in Finland, seasonal variations in radon concentration, the effect of house construction and ventilation and also with the radiation dose from indoor radon and terrestrial gamma radiation. The results are based on radon measurements in approximately 4000 dwellings and on air exchange measurements in 250 dwellings as well as on model calculations. The results confirm that convective soil air flow is by far the most important source of indoor radon in Finnish low-rise residential housing. (97 refs., 61 figs., 30 tabs.)

  15. Measurements of radon daughter concentrations in structures built on or near uranium mine tailings

    International Nuclear Information System (INIS)

    Haywood, F.F.; Kerr, G.D.; Goldsmith, W.A.; Perdue, P.T.; Thorngate, J.H.

    1976-01-01

    A technique is discussed that has been used to measure air concentrations of short-lived daughters of 222 Rn in residential and commercial structures built on or near uranium mill tailings in the western part of the United States. In this technique, the concentrations 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. A computer program is available to calculate the concentrations of RaA, RaB, and RaC in air and to estimate the accuracy in these calculated concentrations. This program is written in the BASIC language. Also discussed in this paper are the alpha-particle spectrometer used to count activity on the air filters and the results of our radon daughter measurements in Colorado, Utah, and New Mexico. These results and results of other measurements discussed in a companion paper are now being used in a comprehensive study of potential radiation exposures to the public from uranium mill tailing piles

  16. Laboratory measurements of the influence of air treatment devices on radon daughters

    International Nuclear Information System (INIS)

    Rajala, M.; Janka, K.; Graeffe, G.; Kulmala, V.; Lehtimaeki, M.

    1984-01-01

    This paper presents laboratory measurements in which the effect of air cleaners on radon decay products has been studied. Experiments show that both a high-efficiency particulate air filter and an electrostatic precipitator substantially decrease the total airborne radon daughter concentration leading to a situation where most of the decay products are unattached. However, in some situations the concentration of fine particles generated by the corona discharge in the electronic air cleaner becomes high enough to increase the total radon daughter concentration and decrease the free decay product concentration. Impurities in the air may have a notable role in the formation of these condensation nuclei. (Author)

  17. Measurement of radon, radon daughters and thoron concentrations by multi-detector devices. No. E/12

    International Nuclear Information System (INIS)

    Somogyi, G.; Varga, Zs.

    1983-01-01

    There is a growing interest in collection of data concerning human exposures to naturally occurring alpha-emitting radionuclides (e.g. in mines, dwellings, building materials, industrial wastes, coal fuel cycle, water supply, soil, plants, etc.). Most of such studies are incomplete for the following reasons: in radon measurements the contribution of thoron is generally neglected, the determination of equilibrium factor is complicated or not possible at all, short- and long-term concentration fluctuations cause difficulties in obtaining representative mean values, the plate-out effect is generally not taken into account. A variety of simple methods were studied that could be used to overcome some of these difficulties by using cups equipped with two or more alpha-sensitive nuclear track detectors. A theoretical foundation of the quantitative measurements with such devices is presented. Experimental data are reported on radon, radon daughters and thoron concentrations measured by multi-detector devices in cave soil gas and in air of Hungarian dwellings. (author)

  18. Carcinogenic effects of radon daughters, uranium ore dust and cigarette smoke in beagle dogs

    International Nuclear Information System (INIS)

    Cross, F.T.; Palmer, R.F.; Filipy, R.E.; Dagle, G.E.; Stuart, B.O.

    1982-01-01

    The development of pulmonary lesions in beagle dogs was studied following chronic inhalation exposures to radon (at 105 +- 20 nCi/l), radon daughters (at 605 +- 169 WL), uranium ore dust (at 12.9 +- 6.7 mg/m 3 ) and cigarette smoke. Chronic exposures to mixtures of these agents caused significant lifespan shortening compared with controls. Survival times of controls and smoke-exposed dogs were equivalent during the 4 to 5-yr mean survival time of the dogs exposed to radon-daughter and ore-dust mixtures (with or without added cigarette smoke). Animals with tumors of the respiratory tract generally has cumulative radon-daughter exposures exceeding 13,000 WLM; their survival time was longer than that of nontumor-bearing animals. Exposure to cigarette smoke had a mitigating effect on radon daughter-induced tumors. Exposures to smoke from 10 cigarettes/d, 7 d/wk produced no significant respiratory tract lesions. Exposure to 20 cigarettes/d, 7 d/wk resulted in pulmonary emphysema, fibrosis and chronic bronchitis and bronchiolitis. Emphysema and fibrosis were much more prevalent and severe in the dogs exposed to mixtures including radon daughters and uranium/ore dust. These dogs also had adenomatous lesions which progressed to squamous metaplasia of alveolar epithelium, epidermoid carcinoma and bronchioloalveolar carcinoma. Pathologic changes in the airways of these dogs were most prominent in the nasal mucosa, and included a few squamous carcinomas in the nasal cavity. (author)

  19. Mine engineering and ventilation problems unique to the control of radon daughters

    International Nuclear Information System (INIS)

    Rock, R.L.

    1975-01-01

    Quality and quantity of ventilation are the two interrelated but key factors in any radon-daughter control programme. The better the intake air quality (little or no contamination from radon and its daughters), the less are the total air requirements for ventilation of active mining areas. Engineering principles for quantity distribution of air through underground working areas are straightforward and the formulae and theories governing forced ventilation are not within the scope of this paper. Rather, this paper discusses the principal methods of utilizing mine planning to facilitate radon-daughter control and also treats the more subtle features of mine ventilation which are especially critical in the ventilation of mines where radon gas constitutes an environmental contamination problem. (author)

  20. Technical evaluation of a radon daughter continuous monitor in an underground uranium mine

    International Nuclear Information System (INIS)

    Bigu, J.; Grenier, M.

    1982-07-01

    An evaluation of a radon daughter monitor was carried out in an underground uranium mine. The monitor operates on continuous sampling and time integrating principles. Experimental and theoretical data were compared. Experimental results show that the monitor underestimates the Working Level, a fact which is partly attributed to plate-out of decay products in the monitor sampling head. However, a correction factor experimentally determined by standard calibration procedures can be programmed into the monitor to take into account losses by plate-out and other losses. Although the monitor was originally designed for radon daughters, it can equally be used in thoron daughter atmospheres and radon daughter/thoron daughter mixtures such as those encountered in some Canadian uranium mines. An analytical procedure is outlined to allow the calculation of Working Levels in radon daughter/thoron daughter atmospheres from the monitor α-count rate. The memory capability of the monitor should make it quite useful and flexible in underground and surface environments in the uranium mining industry

  1. Risks from Radon: Reconciling Miner and Residential Epidemiology

    International Nuclear Information System (INIS)

    Chambers, Douglas B.; Harley, Naomi H.

    2008-01-01

    Everyone is exposed to radon, an inert radioactive gas that occurs naturally and is present everywhere in the atmosphere. The annual dose from radon and its (short-lived) decay products is typically about one-half of the dose received by members of the public from all natural sources of ionizing radiation. Data on exposures and consequent effects have recently been reviewed by the National Council on Radiation Protection and Measurements (NCRP) and the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). Studies of underground miners provides a well-established basis for estimating risks from occupational exposures to radon and for studying factors that may affect the dose response relationship such as the reduction of risk (coefficients) with increasing time since exposure. Miners' studies previously formed the basis for estimating risks to people exposed to radon at home, with downward extrapolation from exposures in mines to residential levels of radon. Presently, the risk estimates from residential studies are adequate to estimate radon risks in homes. Although there are major uncertainties in extrapolating the risks of exposure to radon from the miner studies to assessing risks in the home, there is remarkably good agreement between the average of risk factors derived from miner studies and those from pooled residential case-control studies. There are now over 20 analytical studies of residential radon and lung cancer. These studies typically assess the relative risk from exposure to radon based on estimates of residential exposure over a period of 25 to 30 years prior to diagnosis of lung cancer. Recent pooled analyses of residential case-control studies support a small but detectable lung cancer risk from residential exposure, and this risk increases with increasing concentrations. The excess relative risk of lung cancer from long-term residential exposure is about the same for both smokers and non-smokers; however, because the

  2. Present practices of the Department of National Health and Welfare for the area monitoring of radon and daughter products

    International Nuclear Information System (INIS)

    Taniguchi, H.

    1977-01-01

    The present practices of the Radiation Protection Bureau for the measurement of radon and daughter products have been briefly described. For radon gas, the Lucas chamber method is in use. Short-lived radon daughter products are determined by the modified Kusnetz method. These field methods are supported by radioanalytical procedures carried out at the environmental radioactivity laboratory. Some recent studies using these methods have been briefly summarized. Concentrations of daughter products up to 29 WL were found in a columbium mine and 63 WL in a tin mine under development. The level of radon daughters in some homes in a uranium mining community ranged up to 2 WL

  3. The importance of radon and its daughter products in environmental hygiene

    International Nuclear Information System (INIS)

    Schuettmann, W.

    1985-01-01

    Radon and its daughter products have recently been paid great attention as components of natural ionizing radiation. Their presence in houses and flats are focus of interest. The radon isotopes and their short-lived daughter products are represented briefly, followed by a condensed survey of the historical development of this topic. There are various reasons why this became topical only 80 years after radon had been proved in the atmospheric air. After the listing of the different sources of radon, a rough risk estimation is given regarding the role of radon in lung cancer incidence in the GDR. For environmental hygiene the houses with particularly high radon content of the air, the causes of which are given, are of special importance. Among these causes the ventilation of rooms is the factor having the greatest influence on the radon concentration. From the evidence of occasional, extremely high radon values efforts are derived to elaborate limits of radon concentrations in flats. Finally, the priority of the radon problem for environmental hygiene is pointed out by indicating the current interest of this problem in literature and at congresses. (author)

  4. Residential radon and lung cancer incidence in a Danish cohort

    DEFF Research Database (Denmark)

    Bräuner, Elvira Vaclavik; Andersen, Claus Erik; Sørensen, Mette

    2012-01-01

    High-level occupational radon exposure is an established risk factor for lung cancer. We assessed the long-term association between residential radon and lung cancer risk using a prospective Danish cohort using 57,053 persons recruited during 1993–1997. We followed each cohort member for cancer...... occurrence until 27 June 2006, identifying 589 lung cancer cases. We traced residential addresses from 1 January 1971 until 27 June 2006 and calculated radon at each of these addresses using information from central databases regarding geology and house construction. Cox proportional hazards models were used...... to estimate incidence rate ratios (IRR) and 95% confidence intervals (CI) for lung cancer risk associated with residential radon exposure with and without adjustment for sex, smoking variables, education, socio-economic status, occupation, body mass index, air pollution and consumption of fruit and alcohol...

  5. International intercalibration and intercomparison programme for radon, thoron and daughters measuring equipment. Part. 1: Radon measurement

    International Nuclear Information System (INIS)

    Knutson, E.O.; Solomon, S.B.

    1986-01-01

    The International Intercalibration and Intercomparison Programme for Radon, Thoron and Daughters Monitoring Equipment, abbreviated IIIP, is a program organized jointly by Nuclear Energy Agency of the Organization for Economic Cooperation and Development and the Radiation Protection Research Programme of the Commission of European Communities. The broad purpose of the IIIP is to determine if the somewhat diverse calibration procedures used in different countries are equivalent. The general approach was to select four regional reference laboratories and entrust them with the details of project definition and execution. The four selected laboratories are: Australian Radiation Laboratory, US DOE Environmental Measurements Laboratory, UK National Radiation Protection Board, US DOI Bureau of Mines. The Organizing Committee that selected the four laboratories remained intact and served an oversight function in all work to date

  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. Radon and radon daughters in public, private and commercial buildings in communities associated with uranium mining and processing in Canada

    International Nuclear Information System (INIS)

    Eaton, R.S.

    1982-01-01

    The elevated indoor radon levels in certain communities in Canada have been studied. An overview of the investigational and remedial action programs are presented in this paper. It is suggested that radon daughter concentrations can be controlled by: (a) removing source; (b) placing a barrier between the source and the living space; (c) diverting the radon before it enters a building: (d) increasing the ventilation rate. All methods have been proven but no one technique is the most cost effective because of widely varying conditions found in older housing

  8. Procedure manual for the estimation of average indoor radon-daughter concentrations using the radon grab-sampling method

    International Nuclear Information System (INIS)

    George, J.L.

    1986-04-01

    The US Department of Energy (DOE) Office of Remedial Action and Waste Technology established the Technical Measurements Center to provide standardization, calibration, comparability, verification of data, quality assurance, and cost-effectiveness for the measurement requirements of DOE remedial action programs. One of the remedial-action measurement needs is the estimation of average indoor radon-daughter concentration. One method for accomplishing such estimations in support of DOE remedial action programs is the radon grab-sampling method. This manual describes procedures for radon grab sampling, with the application specifically directed to the estimation of average indoor radon-daughter concentration (RDC) in highly ventilated structures. This particular application of the measurement method is for cases where RDC estimates derived from long-term integrated measurements under occupied conditions are below the standard and where the structure being evaluated is considered to be highly ventilated. The radon grab-sampling method requires that sampling be conducted under standard maximized conditions. Briefly, the procedure for radon grab sampling involves the following steps: selection of sampling and counting equipment; sample acquisition and processing, including data reduction; calibration of equipment, including provisions to correct for pressure effects when sampling at various elevations; and incorporation of quality-control and assurance measures. This manual describes each of the above steps in detail and presents an example of a step-by-step radon grab-sampling procedure using a scintillation cell

  9. Indoor concentrations of radon 222 and its daughters: sources, range, and environmental influences

    International Nuclear Information System (INIS)

    Nero, A.V. Jr.

    1985-04-01

    The author here reviews what is presently known about factors affecting indoor concentrations of radon 222 and its daughters. In US single-family homes, radon concentrations are found to average about 1.5 pCi/1, but substantially higher concentrations occur frequently: perhaps a million US homes have concentrations exceeding 8 pCi/1 (from which occupants receive radiation doses comparable to those now experienced by uranium miners). The major contributor to indoor radon is ordinary soil underlying homes, with this radon being transported indoors primarily by the slight depressurization that occurs toward the bottom of a house interior (due to indoor-outdoor temperature differences and winds). Water from underground sources contributes significantly in a minority of cases, primarily residences with private wells, with public water supplies contributing only a few percent of indoor radon, even when drawn from wells. The strong variability in indoor concentrations is associated primarily with variability in the amount of radon entering homes from these various sources, and secondarily with differences in ventilation rates. However, for a given entry rate, the ventilation rate is the key determinant of indoor concentrations. Human doses are also influenced strongly by the chemical behavior of the daughters (i.e., decay products of radon), and considerable progress has been made recently in investigating a major aspect of this behavior, i.e., the manner in which daughters attach to airborne particles, to walls, and - indeed - to the lining of the lung itself, where the key radiation dose occurs

  10. Combined effects of inhalation of Radon daughter products and tobacco smoke

    International Nuclear Information System (INIS)

    Chameaud, J.; Perraud, R.; Chretien, J.; Masse, R.; Lafuma, J.

    1980-01-01

    Over the last 10 years, more than 500 lung cancers have been induced in rats by inhalations of radon daughter products at various concentrations and cumulated doses. These cancers were compared with human cancers. Another study examines the cocarcinogenic effect of tobacco smoke. In the first experiment, 100 rats were exposed to a 4000-WLM (working level month) cumulated dose of radon daughter products. Fifty animals were then administered tobacco smoke by inhalation in a fume box during 5 months (i.e., for a total of 352 hr). In the group inhaling radon only, 17 cancers appeared; in the radon-tobacco group, 32 cancers were observed, many of them larger and more invasive than those seen in animals exposed to radon only. Under the same conditions tobacco smoke was inhaled by rats previously exposed to lower doses of radon daughter products (two groups of 30 rats each, at 500 and 100 WLM, respectively). Again, the number of cancers observed was greater than the number of cancers expected if the rats had inhaled radon only. The carcinogenic and potentiating action of tobacco smoke was clearly demonstrated

  11. 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)

  12. Comparative toxicity in rats vs hamsters of inhaled radon daughters with and without uranium ore dust

    International Nuclear Information System (INIS)

    Gaven, J.C.; Palmer, R.F.; McDonald, K.E.; Lund, J.E.; Stuart, B.O.

    1977-01-01

    Simultaneous exposures of rats and hamsters to inhaled radon daughters, with and without uranium ore dust, were performed daily for five months. Pulmonary pathology developing in 6 to 13 mo after cessation of daily exposures included interstitial fibrosis, emphysema, epithelial hyperplasia, squamous metaplasia, and malignant neoplasia. Rats showed a greater variety and more severe response to these uranium mine inhalation exposures than did hamsters. Inhalation of radon daughters with uranium ore dust displayed the site of greatest damage, including squamous carcinoma, from the nasopharynx to the lungs. Sixty percent of the rats exposed to radon daughters with ore dust developed primary pulmonary carcinomas, providing an appropriate short-term experimental animal model for investigation of respiratory tract carcinogenesis in uranium miners

  13. An experimental chamber simulating the equilibrium between radon and its daughters in mine air

    International Nuclear Information System (INIS)

    Domanski, T.; Chruscielewski, W.; Orzechowski, W.

    1981-01-01

    An experimental chamber simulating the equilibrium between radon and its daughters in uranium mine air is described. The apparatus is useful for testing track detectors, air samplers, masks and filters and for determining occupational exposures. Increasing the humidity of the chamber air and increasing the amounts of aerosol injected both increase the values of the equilibrium factor, F. The equilibrium in the chamber air decreases after the aerosol injection but by using controlled pulse injections it was shown that the stability of F could be maintained inside the chamber for 4 hours. Results are also given for the structure of the equilibrium between radon and its daughters Qsub(i)/Q 0 in the chamber air as a function of the chamber air factor F and also for the potential α-energy of unattached products in relation to the total α-potential energy of radon daughter products in the chamber air as a function of factor F. (U.K.)

  14. The effect of filtration on radon daughter atmospheres: Laboratory and field experiments

    International Nuclear Information System (INIS)

    Jonassen, N.; Jensen, B.

    1987-01-01

    Airborne radon daughters may be removed from the air by internal filtration using mechanical or electrofilters. The effect of the filtration may be evaluated in absolute measure by the decrease in the potential alpha energy concentration (or equivalent equilibrium concentration) or relatively by the decrease in the equilibrium factor. The filtration, however, may also change the distribution of airborne radon daughter activity between the unattached and the aerosol-attached state in a way to increase the radiological dose corresponding to a given potential alpha energy concentration. The paper describes a series of laboratory and field experiments which indicate that it is possible by the use of household electrofilters with filtration rates of 2-3 h -1 to lower the radon daughter concentrations to about 20 -30 % and the average radiological dose to about 50-60 % of the value in unfiltered air

  15. A review of instrumentation for determination of radon and its daughters concentration

    International Nuclear Information System (INIS)

    Kurosawa, Ryuhei

    1989-01-01

    The aim of the review is to provide the aid for selection and understanding of the radon and its daughters measurement techniques which have been developed for radiation protection activities in various environments such as working of living environment. The practical purpose of the measurement for surveillance in environmental situation is the dose estimation for the public due to the inhalation of natural occurring radioactive materials. The techniques for the determination of radon and thoron concentratin by the active methods with the grab and continuous sampling, and also structures of radon monitors of various passive type are described. Explanation was made on the typical instruments for the determination of the potential alpha energy concentration (PAEC) of radon daughters by the various detecting systems such as solid state detector, and for the estimation of integrated PAEC in the various environments by the PAEC monitors using the cellulose nitrate film or TLD elements (author)

  16. Ventilation systems as an effective tool for control of radon daughter concentration in mines

    International Nuclear Information System (INIS)

    Dory, A.B.

    1981-10-01

    Introduced with a brief discussion of the key role of ventilation in controlling mine atmospheres, the effects of the design of the ventilation system on the control of radon daughter concentrations are illustrated with specific reference to Alcan's Director Mine, St-Lawrence, Nfld. (This fluorspar mine was found to have high radon concentrations due to mine water bringing in dissolved radon.) After a discussion of the health physics history of the mine, the various phases of the ventilation system design and the general results are detailed. The author draws some conclusions having general application to the design of any mine with a radon or thoron daughter concentration. These include minimizing the 'age' of the air; the need for continuous ventilation in all areas; the value of remote control and monitoring; and the benefits of mine pressurization

  17. The reduction of airborne radon daughter concentration by plateout on an air mixing fan

    International Nuclear Information System (INIS)

    Holub, R.F.; Droullard, R.F.; Ho, W.L.; Hopke, P.K.; Parsley, R.; Stukel, J.J.

    1979-01-01

    A series of experiments have been made in the U.S. Bureau of Mines Radon Test Chamber to study the effects of condensation nuclei, humidity and turbulence on the rapid deposition or plateout of radon daughter activity on the chamber walls. Under low humidity conditions the presence of a small fan reduced the working level by 41%. The activity was not deposited on the walls by the turbulent flow from the fan but actually became attached to the fan blades. High relative humidity (> 80%) totally inhibited this observed effect. A detailed mechanism for transport of the daughter species seems to be the critical factor in interpreting the experimental results. (author)

  18. Ventilation systems as an effective tool for control of radon daughter concentration in mines

    International Nuclear Information System (INIS)

    Dory, A.B.

    1981-10-01

    Experience in mines shows that a very high concentration of radon daughters builds up in an unventilated dead end heading. Even minimal air movement results in a drastic reduction in radon daughter concentration. Designing the ventilation system to provide an optimized flow of fresh air into the workplace results in acceptable climatic conditions and radon daughter levels. The example of the Director fluorospar mine in Newfoundland is used to illustrate the actual design and operation of a ventilation system that provided effective radon daughter control. It was found at this mine that the age of the air underground should be kept as low as possible; that no areas of the mine should be left unventilated unless they could be kept at negative pressure; that a comparatively simple remote control and monitoring system helped stabilize ventilation and detected upsets; that the ventilation system should operate continuously, even when the mine is shut down for short periods; and that pressurization of the mine seemed to inhibit radon influx

  19. Experimental study of the combined effects of inhalation of radon daughter products and tobacco smoke

    International Nuclear Information System (INIS)

    Chameaud, J.; Perraud, R.; Chretien, J.; Masse, R.; Lafuma, J.

    1979-01-01

    For 10 years, over 500 lung cancers have been induced in rats by inhalations of radon daughter products at various concentrations and cumulated doses. Considering several points and the dose-effect relationship especially, such cancers can be compared with human cancers. This type of experiments, fully mastered, has made it possible to undertake under good conditions the study of the co-carcinogenic effect of various inhaled pollutants such as tobacco smoke. In a first experiment, 100 rats were exposed to a 4000WLM cumulated dose of radon daughter products, knowing that this level induces some 30% of lung cancers. 50 animals were then administered tobacco smoke by inhalation in a fume box during 5 months (350 h.) In the group inhaling radon only, 17 cancers appeared; in the radon -tobacco group 32 cancers bigger and more invasive were observed. Under the same conditions, tobacco smoke was inhaled by rats previously exposed to lower doses of radon daughter products (2 groups of 30 rats, 500 and 100 WLM respectively). Again, the number of cancers observed was higher that the number of cancers expected if the rats had inhaled radon only. This co-carcinogenic and potentiating action of tobacco was clearly demonstrated. Further experiments are considered in order to determine the processes involved

  20. Recent trends in monitoring radon and daughter products in Indian uranium mines

    International Nuclear Information System (INIS)

    Khan, A.H.; Raghavayya, M.

    1977-01-01

    Uranium mining is of comparatively recent origin in India. In keeping with the ICRP (1959) and IAEA (1967) recommendations on the subject, the radiation practice in this country has been to monitor the mine air for radon. But the fact that radon daughter products are responsible for a major contribution to the radiation dose to the lungs and the comparative ease of correlating incidence of lung cancer with cumulative exposure to radon daughters (WLM), as demonstrated by epidemiologists, cannot be lost sight of. The results of a series of simultaneous measurements of radon, its decay products and their unattached fractions are presented. These measurements of radon have been carried out under different operational and passive conditions in mines. It has been observed that in the mine air, not only RaA but significant fractions of RaB and RaC too, exist in 'free state'. Wide variations have been observed in the unattached fractions with median values around 6% for RaA, 3% for RaB and 1% for RaC. The unattached daughter activities in the return air are maximum under passive conditions and show declining trend as the mining operations assume momentum causing increase in the aerosol concentrations. Relative merits of monitoring the mine air for radon and/or its decay products are also discussed

  1. 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

  2. Aerosol properties and unattached fraction of radon daughters close to the human face

    International Nuclear Information System (INIS)

    Eklund, P.; Bohgard, M

    1993-01-01

    The characterization of the air in a dwelling with a radon problem can be done by measuring several parameters, such as radon concentration, radon daughter concentration, passive and active aerosol size distribution, unattached fraction etc. This is often done by placing the monitors at a certain location in the room, for example 1 m above the floor and away from the walls. The question then is: is this sampled air representative for the air that we breathe, that is, the air close to the face. In this study we have investigated two of the parameters: the size distribution of the inactive aerosol, and the unattached fraction of the activity concentration. (author)

  3. Investigation on residential radon concentration in Jingchuan county

    International Nuclear Information System (INIS)

    Zhang Wei; Wan Yihong; Chen Hongxiao; Shang Bin

    2009-01-01

    This paper reports an investigated result of residential radon concentration in Jingchuan County, Gansu Province, during May 2004 to November 2006. Alpha track detectors were used to measure radon level. Construction types of house and percentages of residents living in the county were also investigated through questionnaires. The result showed that the mean radon concentration in 62 investigated houses was 96.2 Bq·m -3 . The radon concentration in cave dwelling was the highest among all type of dwellings. The average level in cave dwelling is 110.2 Bq·m -3 , which was significantly higher than the national mean value published in literatures, and exceed the WHO recommended value of 100 Bq·m -3 . A considerable number of rural residents are living in cave dwellings in Jingchuan County. Attention should be paid to the radon problem and some proper protection measures taken. (authors)

  4. Estimation of radon daughter levels in the ventilation planning of an underground uranium mine

    International Nuclear Information System (INIS)

    Gan, T.H.; Wise, K.N.; Leach, V.A.

    1981-01-01

    Diffusion parameters determined by laboratory measurements can be utilized for predictions of radon daughter exposures in underground mining environments, as well as providing data for ventilation planning purposes. Wherever possible field measured data for the various diffusion parameters should be used. Underground mining methods, the tunnel model and diffusion theory are considered

  5. Biological effects in beagle dogs of inhaled radon daughters, uranium ore dust, and cigarette smoke

    International Nuclear Information System (INIS)

    Palmer, R.F.; Filipy, R.E.; Stuart, B.O.; Hackett, P.; Ragan, H.A.; McDonald, K.E.

    1975-01-01

    After 5 years of daily inhalation exposures to 600 WL radon daughters plus uranium ore dust and/or cigarette smoking, observed pulmonary lesions include macrophage proliferation, septal fibrosis, epithelial hyperplasia, emphysema, endothelial proliferation, and bronchiolar-alveolar epithelial changes involving multiple foci of squamous metaplasia with atypia. Epithelial neoplasms were found in the respiratory tracts of three dogs. (U.S.)

  6. Protocol for the estimation of average indoor radon-daughter concentrations: Second edition

    International Nuclear Information System (INIS)

    Langner, G.H. Jr.; Pacer, J.C.

    1988-05-01

    The Technical Measurements Center has developed a protocol which specifies the procedures to be used for determining indoor radon-daughter concentrations in support of Department of Energy remedial action programs. This document is the central part of the protocol and is to be used in conjunction with the individual procedure manuals. The manuals contain the information and procedures required to implement the proven methods for estimating average indoor radon-daughter concentration. Proven in this case means that these methods have been determined to provide reasonable assurance that the average radon-daughter concentration within a structure is either above, at, or below the standards established for remedial action programs. This document contains descriptions of the generic aspects of methods used for estimating radon-daughter concentration and provides guidance with respect to method selection for a given situation. It is expected that the latter section of this document will be revised whenever another estimation method is proven to be capable of satisfying the criteria of reasonable assurance and cost minimization. 22 refs., 6 figs., 3 tabs

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

    International Nuclear Information System (INIS)

    Roscoe, R.J.; Stenland, K.; Halperin, W.E.; Waxweiler, R.J.

    1990-01-01

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

  8. Residential radon and lung cancer incidence in a Danish cohort

    Energy Technology Data Exchange (ETDEWEB)

    Braeuner, Elvira V., E-mail: ole@cancer.dk [Diet, Genes and Environment, Danish Cancer Society Research Centre, Copenhagen (Denmark); Danish Building Research Institute, Aalborg University (Denmark); Andersen, Claus E. [Center for Nuclear Technologies, Radiation Research Division, Riso National Laboratory for Sustainable Energy, Technical University of Denmark, Roskilde (Denmark); Sorensen, Mette [Diet, Genes and Environment, Danish Cancer Society Research Centre, Copenhagen (Denmark); Jovanovic Andersen, Zorana [Diet, Genes and Environment, Danish Cancer Society Research Centre, Copenhagen (Denmark); Center for Epidemiology Screening, Department of Public Health, University of Copenhagen (Denmark); Gravesen, Peter [Geological Survey of Denmark and Greenland, Copenhagen (Denmark); Ulbak, Kaare [National Institute of Radiation Protection, Herlev (Denmark); Hertel, Ole [Department of Environmental Science, Aarhus University, Aarhus (Denmark); Pedersen, Camilla [Diet, Genes and Environment, Danish Cancer Society Research Centre, Copenhagen (Denmark); Overvad, Kim [Department of Epidemiology, School of Public Health, Aarhus University, Aarhus (Denmark); Tjonneland, Anne; Raaschou-Nielsen, Ole [Diet, Genes and Environment, Danish Cancer Society Research Centre, Copenhagen (Denmark)

    2012-10-15

    High-level occupational radon exposure is an established risk factor for lung cancer. We assessed the long-term association between residential radon and lung cancer risk using a prospective Danish cohort using 57,053 persons recruited during 1993-1997. We followed each cohort member for cancer occurrence until 27 June 2006, identifying 589 lung cancer cases. We traced residential addresses from 1 January 1971 until 27 June 2006 and calculated radon at each of these addresses using information from central databases regarding geology and house construction. Cox proportional hazards models were used to estimate incidence rate ratios (IRR) and 95% confidence intervals (CI) for lung cancer risk associated with residential radon exposure with and without adjustment for sex, smoking variables, education, socio-economic status, occupation, body mass index, air pollution and consumption of fruit and alcohol. Potential effect modification by sex, traffic-related air pollution and environmental tobacco smoke was assessed. Median estimated radon was 35.8 Bq/m{sup 3}. The adjusted IRR for lung cancer was 1.04 (95% CI: 0.69-1.56) in association with a 100 Bq/m{sup 3} higher radon concentration and 1.67 (95% CI: 0.69-4.04) among non-smokers. We found no evidence of effect modification. We find a positive association between radon and lung cancer risk consistent with previous studies but the role of chance cannot be excluded as these associations were not statistically significant. Our results provide valuable information at the low-level radon dose range.

  9. Residential radon and lung cancer incidence in a Danish cohort

    International Nuclear Information System (INIS)

    Bräuner, Elvira V.; Andersen, Claus E.; Sørensen, Mette; Jovanovic Andersen, Zorana; Gravesen, Peter; Ulbak, Kaare; Hertel, Ole; Pedersen, Camilla; Overvad, Kim; Tjønneland, Anne; Raaschou-Nielsen, Ole

    2012-01-01

    High-level occupational radon exposure is an established risk factor for lung cancer. We assessed the long-term association between residential radon and lung cancer risk using a prospective Danish cohort using 57,053 persons recruited during 1993–1997. We followed each cohort member for cancer occurrence until 27 June 2006, identifying 589 lung cancer cases. We traced residential addresses from 1 January 1971 until 27 June 2006 and calculated radon at each of these addresses using information from central databases regarding geology and house construction. Cox proportional hazards models were used to estimate incidence rate ratios (IRR) and 95% confidence intervals (CI) for lung cancer risk associated with residential radon exposure with and without adjustment for sex, smoking variables, education, socio-economic status, occupation, body mass index, air pollution and consumption of fruit and alcohol. Potential effect modification by sex, traffic-related air pollution and environmental tobacco smoke was assessed. Median estimated radon was 35.8 Bq/m 3 . The adjusted IRR for lung cancer was 1.04 (95% CI: 0.69–1.56) in association with a 100 Bq/m 3 higher radon concentration and 1.67 (95% CI: 0.69–4.04) among non-smokers. We found no evidence of effect modification. We find a positive association between radon and lung cancer risk consistent with previous studies but the role of chance cannot be excluded as these associations were not statistically significant. Our results provide valuable information at the low-level radon dose range.

  10. Lung dose and lung cancer risk by inhalation of radon daughters

    International Nuclear Information System (INIS)

    Jacobi, W.

    1983-01-01

    The inhalation of short-lived radon daughters constitutes the most important occupational radiation exposure in mines, particularly in uranium mines. Among some groups of miners exposed in the past to relatively high radon levels, an excess lung cancer incidence has been observed. In addition to this occupational hazard, the observed radon levels in domestic houses indicate that the inhalation of short-lived radon daughters seems to be the most important component of the radiation exposure of the population from natural sources. For the quantification and judgment of the radiological impact by inhalation of radon daughters in mines as well as in houses, it is necessary to estimate the relationships between the inhaled activity or potential alpha (α) energy of these radionuclides, the dose to target tissues in the lung, and the possible associated lung cancer (LC) risk. It is the purpose of this paper to give a condensed review of our present knowledge in this field and to indicate the main gaps and uncertainties where future research seems necessary

  11. Preliminary findings radon daughter levels in structures constructed on reclaimed Florida phosphate land

    International Nuclear Information System (INIS)

    1975-09-01

    Preliminary results are reported from a survey of the radon daughter levels in structures in Polk County, Florida, built on reclaimed phosphate tailings containing various amounts of 226 Ra. The structures surveyed consisted primarily of private dwellings although a few office buildings were also surveyed. Track-etch films and TLD air samplers were used to measure the levels of radon daughters within the structures and in structures built on non-phosphate land. Radiation levels were converted to WL units (the working level (WL) unit is defined as the potential α energy from the short-lived daughters of Rn which will produce 1.3 x 10 5 MeV in one liter of air). The highest observed level in any structure was 0.2 WL. Possible health hazards to long-time occupants are discussed

  12. A retrospective study of radon daughter concentrations in the workplace in the fluorspar mines of St. Lawrence, Newfoundland

    International Nuclear Information System (INIS)

    Corkhill, D.A.; Dory, A.B.

    1984-07-01

    Fluorspar mining began in St. Lawrence, Newfoundland in the early thirties. In the early years the existing economic and social conditions resulted in poor health and safety practices in the mines. A high incidence of many types of pulmonary diseases, including lung cancer, among the miners was investigated by the Department of National Health and Welfare, and by 1960 radiation in the mines was recognized as the major cause. The original epidemiological study used radon daughter exposure estimates determined from a limited number of radon daughter measurements in one of the mines. Insufficient experience existed at that time to allow a proper technical assessment of the mines and to modify the estimated radon daughter concentrations accordingly. A review of the environmental conditions in the early years of mining and a revision of the estimates of radon daughter concentrations in those mines is presented. Environmental working conditions were determined based on a review of maps, inspectors' reports, Commission hearings, recollections of former workers and of the authors. Comparison to the conditions in the mines in later years, when radiation samples were taken more frequently allowed estimations of the probable radon daughter concentrations that would have existed in the mines earlier. Ranges of estimated average concentrations were made by mines for each year and wherever possible for broad types of job classes. Rather than attempting to propose single numbers for radon daughter concentrations, which in turn might have implied an accuracy that did not exist, ranges of average radon daughter concentrations were estimated

  13. Risks and radiation doses due to residential radon in Germany

    International Nuclear Information System (INIS)

    Beck, T.R.

    2017-01-01

    The population-averaged risk rate and the annual average effective dose due to residential radon in Germany were calculated. The calculations were based on an epidemiological approach taking into account the age- and gender-specific lung cancer incidence rates for the German population and the excess relative risk of 0.16 per 100 Bq.m"-"3 for residential radon. In addition, the risk estimates adjusted for the smoking habits were determined. The population-averaged risk rate for the whole population was estimated with 4.1.10"-"5 y"-"1 (95% confidence interval (CI) 1.4.10"-"5 - 7.6.10"-"5 y"-"1). Residential radon causes a detriment per year of 3.3.10"-"5 y"-"1 (95% CI 1.1.10"-"5 - 6.0.10"-"5 y"-"1), which corresponds to an annual average effective dose of 0.6 mSv (95% CI 0.2-1.1 mSv). Annually, ∼3400 lung cancer incidences are attributed to residential radon. The results from the epidemiological approach exercised in this study are considerably lower than the effective dose, which would be obtained from the dose conversion coefficient calculated using biokinetic and dosimetric models. (author)

  14. Measuring radon source magnitude in residential buildings

    International Nuclear Information System (INIS)

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

    1981-08-01

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

  15. An Alpha spectrometer for measuring radon daughter individual activity concentration

    International Nuclear Information System (INIS)

    Berico, M.; Formignani, M.; Mariotti, F.

    2001-01-01

    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 218 Po, 214 Pb and 214 Bi in air. Radon and thoron effective doses using a dosimetric, instead of an epidemiologic approach, will be then evaluated [it

  16. 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)

  17. Measurement of radon daughters in air samples by alpha spectroscopy

    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 polonium 214 and polonium 218. A known volume of air was passed through a filter, then the alpha activity was directly measured on this filter (Author)

  18. Some measurements of the equilibrium factor for radon daughters in houses

    International Nuclear Information System (INIS)

    Toohey, R.E.; Essling, M.A.; Wang, H.; Rundo, J.

    1982-01-01

    Because the radiation dose to the lung from environmental radon is due almost entirely to the inhalation of the short-lived daughter products, measurements of radon levels alone are not sufficient to determine the dose. Typically the activities of the daughter products in air are not in daughters themselves. The working level (WL) was introduced as a convenient unit to overcome this problem in uranium mines, and it is also applicable to other environments where radiation dosimetry is the principal concern. Since it is easier to determine the radon concentration than the working level, the task of determining lung doses would be simplified if those factors which determine equilibrium could be identified and their effects quantified. In order to do this, simultaneous measurements of radon concentrations and working levels must be made in houses under a variety of conditions. In addition, parameters that may affect the equilibrium factor, such as aerosol concentration and ventilation rate, must also be identified and monitored. Although the effects of such parameters may be best determined under controlled conditions in a laboratory, the results must be validated by measurements in houses. This paper describes these measurements

  19. Residential Radon and Brain Tumour Incidence in a Danish Cohort

    DEFF Research Database (Denmark)

    Bräuner, Elvira V.; Andersen, Zorana J.; Andersen, Claus Erik

    2013-01-01

    Background: Increased brain tumour incidence over recent decades may reflect improved diagnostic methods and clinical practice, but remain unexplained. Although estimated doses are low a relationship between radon and brain tumours may exist. Objective: To investigate the long-term effect of expo...... significant associations and exposure-response patterns between long-term residential radon exposure radon in a general population and risk of primary brain tumours, adding new knowledge to this field. This finding could be chance and needs to be challenged in future studies.......Background: Increased brain tumour incidence over recent decades may reflect improved diagnostic methods and clinical practice, but remain unexplained. Although estimated doses are low a relationship between radon and brain tumours may exist. Objective: To investigate the long-term effect...... of exposure to residential radon on the risk of primary brain tumour in a prospective Danish cohort. Methods: During 1993–1997 we recruited 57,053 persons. We followed each cohort member for cancer occurrence from enrolment until 31 December 2009, identifying 121 primary brain tumour cases. We traced...

  20. 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

  1. 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

  2. Investigation of the concentrations of radon-222 and its daughter products in Loutraki spas (Peloponnese, Greece)

    International Nuclear Information System (INIS)

    Kritidis, Panaiotis; Angelou, Panaiotis.

    1984-07-01

    An express variant of the three-interval total alpha-counting filter method being suitable for the determination of elevated concentrations of 222 Rn decay products in air of increased humidity is described. The method has been used for the determination of radon daughters in air in the major radon spas of Loutraki. Concentrations of 222 Rn and 226 Ra in spa water have been determined as well. Annual effective dose equivalents for the personnel and the patients have been estimated. The need of certain radiation protection measures is pointed out. (author)

  3. Recent investigations and conclusions on radiation exposure from radon and its daughters in rooms

    International Nuclear Information System (INIS)

    Willau, E.

    1984-04-01

    Radon and its daughters emanate from structural materials and are concentrated in closed rooms. Measurements were first made in Vienna in concrete and brick buildings. The difference between these two materials is explained by the effect of different window tightness this being lower in the older brick buildings. It is conjectured that plaster is more important than the bulk wall material. In order to test the influence of the geological ground these measurement in Vienna (rubble ground) were complemented by those in Wagrain (shale ground) and the difference again explained by different window tightness. With regard to height above the ground the radon and daughter concentration was found to 2-3 times higher in cellars and at ground flour than at higher levels. The variation of concentration during and after airing was also investigated. (G.Q.)

  4. Control of radon and daughters in uranium mines and calculations on biologic effects

    International Nuclear Information System (INIS)

    Holaday, Duncan A.; Rushing, David E.; Coleman, Richard D.; Woolrich, Paul F.; Kusnetz, Howard L.; Bale, William F.

    2006-01-01

    A long range study under way by the Public Health Service since 1950 seeks to define the effects of uranium mining operations on the health of the miners and to derive data leading to the establishment of a healthful working environment. Although no evidence of health damage has been found among American miners, the European experience points to possible serious health effects. As a preventive measure, steps were therefore taken early in the industry's growth to safeguard the health of the miners. The current bulletin describes the results of the environmental study to date, together with the work of other investigators, with reference to methods of measuring atmospheric concentrations of radon and daughter products, the establishment of a safe working level for radon daughter products, and the development of effective control measures. It is believed that the material presented will be found useful by the industry and others, particularly in evaluating health hazards and in deriving economically feasible control methods

  5. Simulation of radon short lived decay daughters' inhalation using the lung compartmental model

    International Nuclear Information System (INIS)

    Tomulescu, Vlad C.

    2002-01-01

    Radon and its short-lived decay daughters are the main source of radiation on natural ways for population. The radon gas, released from soil, water or construction materials is producing by radioactive decay the following solid daughters: Po-218, Bi-214, Pb-214, and Po-214, which can attach to aerosols, and consequently penetrate the organism by inhalation. The human respiratory tract can be approximated by aid of a compartment model that takes into account the different anatomical structures exposed to contamination and irradiation, as well as the respective physiological processes. This model is associated to a mathematical equation system that describes the behavior of the radioactive material inside the body. The results represent the dose equivalent on different organs and tissues, as a function of subject and the activity performed in contaminating environment. (author)

  6. Mean size among the particles of short-lived radon daughter products in the atmosphere

    International Nuclear Information System (INIS)

    Nakatani, S.

    1980-01-01

    The diffusion-battery method is used to classify the radioactive particles according to their sizes. The diffusion coefficient is determined from the fractional penetration of the particles through the battery. Particle radii are derived from the diffusion coefficients with the Stokes-Cunningham-Millikan formula. At the exit and entrance of the battery, individual concentrations of radon daughter products 218 Po, 214 Pb, 214 Bi are determined. Thus the mean sizes of individual radon daughters can be obtained from the fractional penetration of individual nuclides through the diffusion battery. Despite large statistical fluctuations the mean size of 214 Bi is always shifted toward the larger size region as compared with those of other radionuclides

  7. Radon and its daughters in the maritime atmosphere near Japan islands

    International Nuclear Information System (INIS)

    Mochizuki, Sadamu

    1982-01-01

    In the maritime atmosphere near the land, natural radon and its daughters dispersed from land to over ocean are found gradually to attain their radioactive equilibrium with time lapse after they left land sources. Radioactive equilibrium is found to be established at the distance 100 - 150 km from the land, at least in winter season. Farther off from the distance about 150 km from the land, radioactive equilibrium will get deviation mode from their equilibrium state. (author)

  8. Non-neoplastic pulmonary disease from inhaled radon daughters with uranium ore dust in beagle dogs

    International Nuclear Information System (INIS)

    Filipy, R.E.; Palmer, R.F.; Stuart, B.O.

    1977-01-01

    Daily exposures of adult beagle dogs to inhaled radon daughters plus uranium ore dust, with and without concurrent cigarette smoking, for 2 to 5-1/2 yr have produced massive pulmonary fibrosis and severe emphysema. The cumulative exposure doses are similar to those associated with a 5-fold or greater increase in death rate of uranium miners due to chronic respiratory insufficiency, including pneumoconiosis, pulmonary fibrosis, and emphysema

  9. CANALPH-3: a portable three-channel alpha spectrometer for measuring the daughter products of radon and thoron

    International Nuclear Information System (INIS)

    Carson, D.W.

    1979-07-01

    A portable three-channel alpha spectrometer for the measurment of radon and thoron daughters in uranium mines or homes is described. The computer programs for analysing the data to give the working levels of radon and thoron by both the alpha spectrometric and modified Kusnetz methods are included along with some typical results

  10. In the ideal condition an experimental study on migration of radon and its daughters in the atmosphere

    International Nuclear Information System (INIS)

    Zeng Bing; Zhang Jinzhao; Wang Qing

    2010-01-01

    According to the relevant theory of thermodynamics, this presentation which based on the radon migration of the cluster theory has deduced ordinarily the ideal velocity period and displacement. The purpose was to establish the theoretical model of migration of radon and its daughters in the atmosphere in the ideal case, which would provide a underlying theoretical basis for the further research. (authors)

  11. Comparison of a continuous working level monitor for radon daughters with conventional grab-sampling

    International Nuclear Information System (INIS)

    Bigu, J.; Grenier, M.

    1982-08-01

    An evaluation of a radon daughter monitor was carried out under laboratory controlled conditions. The monitor operates on continuous sampling and time integrating principles and was tested in conjunction with a newly designed, large radon/thoron room calibration facility. The monitor was tested under constant and rapidly fluctuating radiation conditions. Experimental data obtained with the monitor were compared with data obtained by conventional grab-sampling and with an automated radon daughter/thoron daughter 'grab-sampler'. The Working Level used in the tests ranged from less than 0.01 WL to approximately 10 WL. The measurements were carried out under low aerosol concentration (1 x 10 3 - 2 x 10 3 cm -3 , approximately) to study plate-out effects in the sampling head. Good agreement (within about 10 %) was found between the monitor, conventional grab-sampling and the automated grab-sampler. The monitor should prove quite flexible, useful and reliable for monitoring underground and surface environments in the uranium mining industry

  12. Contribution of radon daughters plated-out in a cylindrical device by track-technique

    Energy Technology Data Exchange (ETDEWEB)

    Hafez, A.F. (Alexandria Univ. (Egypt). Dept. of Physics); Kotb, M.A. (Alexandria Univ. (Egypt). Biophysics Dept.); Toth-Szilagyi, M. (Magyar Tudomanyos Akademia, Debrecen (Hungary). Atommag Kutato Intezete)

    1991-01-01

    CR-39 plastic nuclear track detector is used to measure the fraction of alpha-particle tracks due to radon daughters activities plated-out on the internal walls of a cylindrical-shaped plastic can. Radium chloride solution is used as a radon source, the exposure time is ranged from 4 hours to 3 days. To assess the percentage of plate-out effect on CR-39 nuclear track detector, two different methods were used. In one experiment, a few circular parallel pairs of CR-39 sheets were hanged in the can device. In the other experiment, the estimation of the plate-out effect has been performed, after exposure to the radon source, by detecting tracks with a second unexposed sheet placed in close contact to the exposed wall and detectors. In the two methods, it was found that the chemically etched tracks related to plated-out activities contribute about 50% of the measured alpha-particles tracks. (orig.).

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

    International Nuclear Information System (INIS)

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

    2012-01-01

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

  14. [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.

  15. Radon and thoron daughter activities in the environment of the King George Island (West Antarctica

    Directory of Open Access Journals (Sweden)

    A. T. Solecki

    2005-06-01

    Full Text Available Results of 253 gamma spectrometric analyses of radon daughters in soil and bedrocks of the King George Island (West Antarctica are presented. Measured values range from 0.1 to 58.4 Bq/kg, and from 4.9 to 75.5 Bq/kg for 214Bi and 208Tl respectively, but most measurements fall in the lower part of this range due to predominantly basaltic character of the geological basement. Obtained gamma spectrometric data correspond well to very low soil gas radon content measured by means of Kodak LR115 being below 454 Bqm-3. Low soil gas radon content and characteristic type of architecture is responsible for low indoor radon activity in Arctowski Station being as low as 10- 15 Bqm-3. The highest 105 Bqm-3 indoor Rn activity has been measured in the greenhouse bungalow of the station. This increased value was probably connected with the presence of about 1000 kg of imported soil material in the greenhouse room of the bungalow. Local zones of increased uranium and thorium content, discovered as a result of radiometric mapping, can potentaily influence atmospheric radon used for meteorological interpretation.

  16. Phenomena associated with rain deposition of radon daughters

    Energy Technology Data Exchange (ETDEWEB)

    Fujitaka, Kazunobu [National Inst. of Radiological Sciences, Chiba (Japan)

    1997-02-01

    Since Rn daughter nuclides generated from Rn gas in the air are generally absorbed on aerosol, its radioactivities are apt to deposit onto the ground with raindrop. Here, the effects of raining on the radiation level were investigated. The amount of precipitation was determined using a highly sensitive rain gauge (the nominal sensitivity of 0.0043 mm) and air radioactive level was measured using a scintillation monitor of 2``{phi}x2``NaI(Tl) which was set at 1.5 m height above the ground. The rising of {gamma}-radiation level associated with rainfall was expressed as percentage of the base line activity. The radiation level increased depending on the intervals between the successive rainfalls and the increase of radioactivity from base line was greater when the rainfall interval was less than 12 hours. Therefore, the amount of radiation deposit was suggested to be small when the rainfall interval is short. Ordinarily, the increase of air radiation level caused by rain deposition was thought to be within a range of 20-50%. (M.N.)

  17. 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

  18. Radon and its short-lived daughter products in the lower atmosphere

    International Nuclear Information System (INIS)

    Servant, J.

    1964-01-01

    The variations of vertical and temporal distributions of natural radioactivity with geographical location in the lower atmospheric layers are shown. The content of radon and its short lived daughters products are measured. Radon content is measured continually with a new apparatus, the sensibility of which is 0,2.10 -11 Ci m -3 i.e. the fiftieth of the mean concentration near the soil, this apparatus allowed us to show that radioactive equilibrium between radon and its daughter products is realised when the atmosphere is stable. Air observations between 0 and 100 meters above the ground point out that radon and its decay products are valuable tracers to mark the stability of the atmosphere. Under very stable nighttime conditions the radon accumulates in the former 30 meters of the air layer, at sunrise it ascends and at 9 o'clock attains 100 meters high. The removal rate of the air in the lower atmosphere is computed from the movement of this radon mass, it is equal to 90 per cent for a summer day. We have show that this radon comes from the soil in which it diffuses by brownian motion the intensity of which varies with the water content of the soil, its value for June 1958 is 6,10 -17 Ci cm -2 s -1 and for January 1959 0.2,10 -17 Ci cm -2 s - 1. During the year 1958-1959 general mean of flux for the sedimentary soil studied is equal to 3. 8 ± 1.3, 10 -17 Ci cm -2 s -1 it is identical to the world wide mean computed by H. Israel. In a hilly site in the Morvan, air movements are well marked by this radioactivity. We observed from one hand downslope and up-slope breezes having, respectively, speeds of 0.2 m s -1 and 0.7 m s -1 and from the other hand by night, in the valley and with a light wind favours the stagnation of the air near the ground, a strong increase of the radioactivity which is proportional to the one of the granitic rocks of the region. The radon flux of this soil is 74,10 -17 Ci cm -2 s -1 and the radioactivity of the air can attain 1.5,10 -8 Ci m

  19. Measurement of concentrations of radon and its daughters in indoor atmosphere using CR-39 nuclear track detector

    International Nuclear Information System (INIS)

    Khan, A.J.; Sharma, K.C.; Varshney, A.K.; Prasad, Rajendra; Tyagi, R.K.

    1988-01-01

    The concentrations of radon and its daughters in rooms having different environmental conditions are measured using CR-39 nuclear track detector. It has been found that the radon concentration inside the rooms depends on ventilation, sub-soil emanation and the housed materials. The use of internal wall coverings such as plaster, distemper and white washing may reduce the radon emanation inside the rooms. The use of paints on walls is the best for reducing the radon concentration inside the rooms. (author). 11 refs

  20. Comparison of radon and thoron daughter behaviour in two underground uranium mine environments

    International Nuclear Information System (INIS)

    1985-09-01

    Measurements were made of aerosol concentration and size distribution in 5 locations downstream of working areas in two Canadian uranium mines which use track and trackless mining methods. In the track mining area the aerosol concentration ranged from 3x10 4 to 7x10 4 /cm 3 , averaging 5x10 4 /cm 3 . The highest values were associated with the passage of diesel equipment. The count median diameter of the aerosol varied from 32 to 94 nm, with the smaller sizes associated with the presence of diesel exhaust. The activity median diameter was measured for radon and thoron daughters in each environment. In the track mine the diameter of 218 Po, 214 Pb, 214 Bi averaged 54, 50, 54 nm respectively, and of 212 Pb averaged 70 nm. In the trackless mine, these diameters were 73, 70, 85 and 100 nm, respectively. The activity median diameter in terms of radon Total Potential Alpha Energy was found to be 89 nm

  1. 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

  2. Radon daughter plate-out measurements at SNOLAB for polyethylene and copper

    Energy Technology Data Exchange (ETDEWEB)

    Stein, Matthew; Bauer, Dan; Bunker, Ray; Calkins, Rob; Cooley, Jodi; Loer, Ben; Scorza, Silvia

    2018-02-01

    Polyethylene and copper samples were exposed to the underground air at SNOLAB for approximately three months while several environmental factors were monitored. Predictions of the radon-daughter plate-out rate are compared to the resulting surface activities, obtained from high-sensitivity measurements of alpha emissivity using the XIA UltraLo-1800 spectrometer at SMU. From these measurements, we determine an average $^{210}$Pb plate-out rate of 249 and 423~atoms/day/cm$^{2}$ for polyethylene and copper, respectively, when exposed to radon activity of 135 Bq/m$^{3}$ at SNOLAB. A time-dependent model of alpha activity is discussed for these materials placed in similar environmental conditions.

  3. Calibration of apparatus for short living radon daughters monitoring in air

    International Nuclear Information System (INIS)

    Chalupnik, S.; Lebecka, J.; Skubacz, K.

    1988-01-01

    A liquid scintillation method was developed for absolute measurement of radon daughters concentration in air. Calibration of site IRDM equipment appears as a significant problem. Usually it employs simultaneous measurements with the calibrated device and the reference one, of known detection efficiency. This yields systematic errors resulting from errors in evaluation of the detection efficiency. The presenting method is an absolute one. The efficiency for α and β particles is of about 100%. Thanks to this the developed method is excellent as a comparative one for calibration purposes. (author)

  4. 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

  5. Radon concentrations in residential housing in Hiroshima and Nagasaki

    International Nuclear Information System (INIS)

    Yonehara, Hidenori; Aoyama, Takashi; Radford, E.P.; Kato, Hiroo; Sakanoue, Masanobu.

    1992-01-01

    A measurement of indoor radon ( 222 Rn) concentrations in Hiroshima and Nagasaki was carried out to examine an effect of the exposure on atomic bomb (A-bomb) survivors. Two hundred dwellings (100 from each city), chiefly of members of the Life Span Study population which is a fixed cohort studied by Radiation Effects Research Foundation (RERF), were selected for this survey. We used two types of alpha-track detector: a Terradex detector type SF and a bare-track detector improved by Yonehara et al. Comparative measurements showed that although there was an adequate correlation between the values obtained using the two detectors, the geometric mean value for the bare-track detector was 45% of that for the Terradex detector. This difference was considered to be due to differences in the calibration methods and sensitivities of the detectors to thoron ( 220 Rn). The arithmetic mean values of the radon concentrations for 193 locations in Hiroshima and 192 locations in Nagasaki measured by Terradex SF detector were 103 Bq m -3 and 40.6 Bq m -3 , respectively. The values at 100 locations in Hiroshima and at 93 locations in Nagasaki measured by the bare detector were 43.1. Bq m -3 and 13.6 Bq m -3 , respectively. The significant difference between the geometric mean values of the concentration in Hiroshima and Nagasaki measured by both methods was observed. The difference might be attributable to the different geological environments of the two cities. The difference between the estimated dose equivalents for exposure to radon daughters in dwellings in Hiroshima and Nagasaki over the last 30 years might amount to 0.4 or 0.8 Sv; however, no statistically significant difference was observed in lung cancer mortality in the low-dose range in either city. Nevertheless, the indoor-radon concentrations estimated in this survey could significantly influence the dose-response relationships for A-bomb exposure. (author)

  6. Stratified random sampling plans designed to assist in the determination of radon and radon daughter concentrations in underground uranium mine atmosphere

    International Nuclear Information System (INIS)

    Makepeace, C.E.

    1981-01-01

    Sampling strategies for the monitoring of deleterious agents present in uranium mine air in underground and surface mining areas are described. These methods are designed to prevent overexposure of the lining of the respiratory system of uranium miners to ionizing radiation from radon and radon daughters, and whole body overexposure to external gamma radiation. A detailed description is provided of stratified random sampling monitoring methodology for obtaining baseline data to be used as a reference for subsequent compliance assessment

  7. In situ Ge(Li)-spectrometric measurements of gamma radiation from radon daughters under different weather conditions

    International Nuclear Information System (INIS)

    Finck, R.R.; Persson, B.R.R.

    1980-01-01

    The photon fluence from radionuclides in the ground and air was measured continuously with a Ge(Li) spectrometer during several weeks. The most prominent change in photon fluence rate near the ground was obtained during periods of heavy rainfall. Deposition of the short-lived radon daughters 214 Pb and 214 Bi on the ground surface can cause a temporary increase in the external absorbed dose rate of approximately 2μrads/h. The photon fluence from airborne radon daughters can be correlated to the degree of atmospheric stability. During stable conditions the photon fluence increases and the activity ratio 214 Bi/ 214 Pb decreases

  8. Planning meeting combined analysis, North America residential radon studies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-01

    This report describes the Third International Department of Energy/ Commission of European Communities Workshop on Residential Radon Epidemiology held in February 1995 in Baltimore, MD. This culminates a major effort begun 1988, co-sponsored by the DOE and the CEC Radiation Protection Programme to identify and bring together all those scientists worldwide performing epidemiological case control studies of residential radon and lung cancer. Two prior meetings were held in 1989 and 1991. The goal of this effort is to work with the investigators and to pool these studies to increase their limited statistical power and to maximize any information that could be gained from them. That goal has now been met. At this Workshop the task moved from planning and agreement to implementation, as many of the studies were finally being completed and published. This report provides a summary of the Workshop as well as that of the first implementation workgroup meeting hosted by Health Canada. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

  9. An investigation into control of radon and its daughter products in some Cornish mine atmospheres

    International Nuclear Information System (INIS)

    Dungey, C.J.; Hore, J.; Waller, M.D.

    1979-01-01

    Elements of the uranium series are widespread as trace elements in the granitic rocks in which much of Cornwall's mining takes place. The radon gas, together with its decay or daughter products, can be inhaled by the underground worker. It is now realised that even a small concentration of the gas can be harmful; this is reflected by the tightening of control standards in the U.S.A. by a factor of 30 in the past 10 years. The current standards are such that many non-uranium mines must now provide some means of control. As yet, no statutory limits have been set in the United Kingdom mining regulations, but the industry locally is hopeful of achieving reduced levels that will pre-empt any forthcoming legislation. The first requirement of any control technique is the ability to monitor the effects of any action. An instrument developed recently in the U.S.A. now enables the radon daughter concentration to be determined quickly on the spot, so the effectiveness of any control measures can be evaluated more rapidly. The evaluation of the best potential methods of control requires some understanding of the behaviour of the decay products in typical mine environments. Several control techniques are being tested, both in controlled experimental conditions at the Camborne School of Mines and in field conditions at South Crofty and Wheal Pendarves mines. The experience and results of these tests so far are examined. (author)

  10. Comments upon 'basis of intake limits for radon and thoron daughters'

    International Nuclear Information System (INIS)

    Stewart, C.G.

    1984-05-01

    AECB consultative document C-78 proposes that the different types of exposure in uranium mines should be combined in such a fashion that the sum of the fractions contributing to annual dose (each fraction being the annual exposure of each type divided by the corresponding maximum permissible annual exposure) does not exceed unity. In order for this approach to be valid it is necessary for each of the demoninators to represent the same risk of mortality from malignancy, in this instance mortality from lung cancer where malignancy and mortality are very nearly equal. Document C-78 indicates that the limit of 50 mSv/a for whole body gamma irradiation and 4.7 WLM/a exposure to radon daughters are assumed to carry the same risk of mortality from malignancy. In the following document it is demonstrated that this assumption is not valid and consequently the current recommendations of C-78 for combining risk from gamma radiation and radon daughters are also not tenable

  11. Field monitoring versus individual miner dosimetry of radon daughter products in mines.

    Science.gov (United States)

    Domański, T; Kluszczyński, D; Olszewski, J; Chruscielewski, W

    1989-01-01

    The paper presents the results realised simultaneously by two different and independent systems of measurement of an assessment of miners' exposure to radon daughter products which naturally occur in the air of mines. The first one, called the Air Sampling System (ASS), was based on the field monitoring of radon progeny in air, the second one, called the Individual Dosimetry System (IDS), was based on the individual dosimeters worn by miners. Experimental comparison of these two systems has been conducted for six years in eleven Polish underground metal-ore mines. This study reveals that no correlation exists between the concentration and annual miners' exposures evaluated by the ASS and IDS. The ratio ASS/IDS for mine population varies from 11.0 to 0.14 in respect of annual concentration means, and in respect to annual exposures, this ratio varies from 4.5 to 0.14. The conclusion to be drawn from six years' observation and comparison of both systems is that correct and true evaluation of miners' exposure to radon progeny can be made only by the use of the Individual Dosimetry System, since the Air Sampling System is too sensitive and too dependent on the Strategy of sampling and its radiation.

  12. Radon daughter concentrations in and around dwellings in the northern part of the Netherlands

    International Nuclear Information System (INIS)

    Wolfs, F.; Hofstede, H.; Meijer, R.J. de; Put, L.W.

    1984-01-01

    The concentration of radon daughters in and around 80 dwellings located in the northern part of the Netherlands has been determined using a one-filter method. Median values of 2.0 and 0.4 mWL were measured for the indoor and outdoor concentrations, respectively. The average outdoor concentration was about an order of magnitude higher for wind directions between SE-SW than for SW-NW. On average, dwellings with double pane windows and/or concrete floors were found to have significantly higher radon concentrations than those with single pane windows and/or wooden floors. For the living room of a particular dwelling, 18 measurements were carried out. The data for this dwelling indicate a linear relation between the concentration indoors and outdoors with a slope of 3.8 +- 2.0. This unexpected behaviour is thought to be related to ventilation via the crawl space. Measurements of ventilation patterns and measurements of radon concentrations in the living room and the crawl space are consistent with this picture. (author)

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

    International Nuclear Information System (INIS)

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

    2015-01-01

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

  14. A combined analysis of North American case-control studies of residential radon and lung cancer.

    Science.gov (United States)

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

    2006-04-01

    Cohort studies have consistently shown underground miners exposed to high levels of radon to be at excess risk of lung cancer, and extrapolations based on those results indicate that residential radon may be responsible for nearly 10-15% of all lung cancer deaths per year in the United States. However, case-control studies of residential radon and lung cancer have provided ambiguous evidence of radon lung cancer risks. Regardless, alpha-particle emissions from the short-lived radioactive radon decay products can damage cellular DNA. The possibility that a demonstrated lung carcinogen may be present in large numbers of homes raises a serious public health concern. Thus, a systematic analysis of pooled data from all North American residential radon studies was undertaken to provide a more direct characterization of the public health risk posed by prolonged radon exposure. To evaluate the risk associated with prolonged residential radon exposure, a combined analysis of the primary data from seven large scale case-control studies of residential radon and lung cancer risk was conducted. The combined data set included a total of 4081 cases and 5281 controls, representing the largest aggregation of data on residential radon and lung cancer conducted to date. Residential radon concentrations were determined primarily by a-track detectors placed in the living areas of homes of the study subjects in order to obtain an integrated 1-yr average radon concentration in indoor air. Conditional likelihood regression was used to estimate the excess risk of lung cancer due to residential radon exposure, with adjustment for attained age, sex, study, smoking factors, residential mobility, and completeness of radon measurements. Although the main analyses were based on the combined data set as a whole, we also considered subsets of the data considered to have more accurate radon dosimetry. This included a subset of the data involving 3662 cases and 4966 controls with a-track radon

  15. 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

  16. Interference from radon-thoron daughters in plutonium channel of a continuous plutonium-in-air monitor

    International Nuclear Information System (INIS)

    Pendharkar, K.A.; Krishnamony, S.

    1983-01-01

    This paper summarises the results of a study conducted to define the extent of interference from the daughter products of radon/thoron to the plutonium channel of a continuous plutonium-in-air monitor. The effect on the detection limits of the instrument due to chemical form (transportable or non-transportable) and isotopic composition of plutonium aerosol are briefly discussed. (author)

  17. Radon and radon daughter measurements and methods utilized by EPA's Eastern Environmental Radiation Facility

    International Nuclear Information System (INIS)

    Phillips, C.R.

    1977-01-01

    The Eastern Environmental Radiation Facility (EERF), Office of Radiation Programs, has the responsibility for conducting the Environmental Protection Agency's study of the radiological impact of the phosphate industry. Numerous measurements in structures constructed on land reclaimed from phosphate mining showed that working levels in these structures range from 0.001 to 0.9 WL. Sampling is performed by drawing air through a 0.8 micrometer pore size, 25 mm diameter filter at a flow rate of 10 to 15 liters/minute for from 5 to 20 minutes, depending on the daughter levels anticipated. The detection system consists of a ruggedized silicon surface barrier detector (450 mm 2 -100 micrometer depletion) connected through an appropriate pre-amplifier-amplifier to a 1024-channel multichannel analyzer. Other measurement methods are also discussed

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

    International Nuclear Information System (INIS)

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

    1981-09-01

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

  19. Methods and measurements of indoor levels of radon and its daughter products

    International Nuclear Information System (INIS)

    Subba Ramu, M.C.; Muraleedharan, T.S.; Ramachandran, T.V.; Shaikh, G.N.

    1988-01-01

    General population is exposed, some times, to enhanced levels of radon (Rn) and its progeny concontrations in the indoor environment of dwellings, depending on various parameters like type of construction, location and ventilation features of the dwelling as well as on the occupancy factor. The risk involved in the indoor Rn exposure is briefly discussed in this report. Several methods are available for the measurement of Rn and its daughters in dwellings. This report describes in detail some of the suitable and convenient methods for the measurements. Methods for evluating ventilation rate in dwellings is also given. Grab sampling and time integrated measurements are described. The report also gives the results of some preliminary measurements carried out in some rooms and lecture halls of the Bhabha Atomic Research Centre, Bombay. The results are discussed and conclusions drawn with particular reference to a country-wide survey of Rn exposure. (author)

  20. House characteristics associated with gamma radiation and radon daughter working levels in eastern Pennsylvania

    International Nuclear Information System (INIS)

    Stebbings, J.H.; Dignam, J.J.; Anast, G.A.; Reilly, M.A.; Gerusky, T.M.; Hartman, T.T.

    1988-01-01

    Working levels (WL) of radon daughters and γ measurements in basements are described for ∼ 1200 houses near the Reading Prong. House variables included condition and construction materials of basement floors and walls, basement heights and areas, heating systems, air conditioning, water supply, and presence of drains and sump pumps. WLs were poorly predicted by house characteristics or γ measurements, while γ levels were well predicted by house characteristics and WL. Factors predicting high γ levels tended to be associated with low WLs and vice versa. Dirt basement floors and fieldstone basement walls were strongly associated with high γ levels, as were poor wall conditions in multivariate analyses. Gamma levels were low in electrically heated homes. High WLs were strongly associated with electric heat, low WLs with basement walls of fieldstone and/or in poor condition. Large house volumes and well water supply were also associated with higher WLs. (author)

  1. POSSIBLE ROLE OF INDOOR RADON REDUCTION SYSTEMS IN BACK-DRAFTING RESIDENTIAL COMBUSTION APPLIANCES

    Science.gov (United States)

    The article gives results of a computational sensitivity analysis conducted to identify conditions under which residential active soil depressurization (ASD) systems for indoor radon reduction might contribute to or create back-drafting of natural draft combustion appliances. Par...

  2. Rapid determination of radon daughters and of artificial radionuclides in air by online gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Hoetzl, H.; Winkler, R.

    1993-01-01

    For the determination of airborne radionuclide concentrations in real time, a fixed filter device was constructed which fits directly onto a germanium detector with standard nuclear electronics and a multichannel analyzer buffer connected via a data line to a personal computer for remote control and on-line spectrum evaluation. The on-line gamma-ray spectrometer was applied to the study of radon decay product concentrations in ground-level air and to the rapid detection of only contamination of the environmental air by artificial radionuclides. At Munich-Neuherberg, depending on the meteorological conditions, the measured air concentrations of 214 Pb, the first gamma-ray-emitting member of the 222 Rn decay series, varied from about 1 to 50 Bq m -3 . For the artifical radionuclides 60 Co, 131 I and 137 Cs the detection limits were determined as a function of the varying natural radon daughter concentrations at sampling and counting times of 1 h or 1 day. For these radionuclides minimum detectable air activity concentrations of 0.3 or 0.001 Bq m -3 , respectively, were obtained at low radon daughter levels. At high radon daughter levels the respective detection limits were found to be higher by a factor of only about 2. (orig.)

  3. Rapid determination of radon daughters and of artificial radionuclides in air by online gamma-ray spectrometry

    Energy Technology Data Exchange (ETDEWEB)

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

    1993-04-01

    For the determination of airborne radionuclide concentrations in real time, a fixed filter device was constructed which fits directly onto a germanium detector with standard nuclear electronics and a multichannel analyzer buffer connected via a data line to a personal computer for remote control and on-line spectrum evaluation. The on-line gamma-ray spectrometer was applied to the study of radon decay product concentrations in ground-level air and to the rapid detection of only contamination of the environmental air by artificial radionuclides. At Munich-Neuherberg, depending on the meteorological conditions, the measured air concentrations of [sup 214]Pb, the first gamma-ray-emitting member of the [sup 222]Rn decay series, varied from about 1 to 50 Bq m[sup -3]. For the artifical radionuclides [sup 60]Co, [sup 131]I and [sup 137]Cs the detection limits were determined as a function of the varying natural radon daughter concentrations at sampling and counting times of 1 h or 1 day. For these radionuclides minimum detectable air activity concentrations of 0.3 or 0.001 Bq m[sup -3], respectively, were obtained at low radon daughter levels. At high radon daughter levels the respective detection limits were found to be higher by a factor of only about 2. (orig.).

  4. Seasonal variation of radon daughters concentrations in the atmosphere and in precipitation at the Japanese coast of the Sea of Japan

    International Nuclear Information System (INIS)

    Nishikawa, T.; Okabe, S.; Aoki, M.

    1988-01-01

    The atmospheric radon daughters concentration at Fukui in the Japanese coastal region of the Sea of Japan shows a seasonal variation whose high values appear in summer and low values in winter. On the other hand, the radon daughters concentration in precipitation at Fukui and that in the maritime atmosphere over the Sea of Japan are high in winter and low in summer. It is concluded from these phenomena that the greater part of the continental radon and its daughters are transported by seasonal winds from Siberia and China to Japan across the Sea of Japan in winter. However, when the air masses approach the shore, the cumulonimbus grows and the heavy snowfall scavenges out the radon daughters from the air masses in large quantities at the Japanese coastal region of the Sea of Japan. (author)

  5. 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.

  6. Some comments on the feasibility of an epidemiological study on incidence of lung cancer due to exposure to radon daughters

    International Nuclear Information System (INIS)

    Elsasser, U.

    1988-01-01

    For two different designs of a study - cohort and case control study - estimates of required sample size have been made on the basis of lung cancer risk assessment data for exposure to radon and radon daughters. The estimates have shown that a cohort study is not feasible for reasons of unjustifiably high requirements. A case control study, however, may contribute to clarifying the lung cancer risk, especially if the basic overall entity is limited to the population group of over 50 years of age. (orig.) [de

  7. Estimate of lifetime excess lung cancer risk due to indoor exposure to natural radon-222 daughters in Korea

    International Nuclear Information System (INIS)

    Si-Young Chang; Jeong-Ho Lee; Chung-Woo Ha

    1993-01-01

    Lifetime excess lung cancer risk due to indoor 222 Rn daughters exposure in Korea was quantitatively estimated by a modified relative risk projection model proposed by the U.S. National Academy of Science and the recent Korean life table data. The lifetime excess risk of lung cancer death attributable to annual constant exposure to Korean indoor radon daughters was estimated to be about 230/10 6 per WLM, which seemed to be nearly in the median of the range of 150-450/10 6 per WLM reported by the UNSCEAR in 1988. (1 fig., 2 tabs.)

  8. Radon and radon daughters' concentration in spring and wells waters from Presidente Prudente: preliminary results; Concentracao de Rn-222 e filhos em aguas provenientes de pocos e emergencias de agua da regiao de Presidente Prudente: resultados preliminares

    Energy Technology Data Exchange (ETDEWEB)

    Osorio, Ana Maria Araya; Saenz, Carlos Alberto Tello [Universidade Estadual Paulista Julio de Mesquita Filho (FCT/UNESP), Presidente Prudente, SP (Brazil). Departamento de Fisica Quimica e Biologia; Aguiar, Claudinei Rodrigues de [Universidade Tecnologica Federal do Parana (UTFPR), PR (Brazil); Pereira, Luiz Augusto Stuani [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Presidente Prudente, SP (Brazil)

    2009-07-15

    This work presents the preliminary results about the concentration of radon and radon daughters in wells and springs water from Presidente Prudente. Six water samples were studied: three from well-water, two from springs water and one from potable water. For the determination of α-activity the samples were placed inside plastic containers where the CR-39 tracks detectors were outside the water. The track density of α-particles were measured by using optical microscopy. The results show that one sample from well-water presented higher concentration of radon and radon daughters than the other samples. (author)

  9. Respiratory tract carcinogenesis in large and small experimental animal following daily inhalation of radon daughters and uranium ore dust

    International Nuclear Information System (INIS)

    Stuart, B.O.; Palmer, R.F.; Filipy, R.E.; Dagle, G.E.; McDonald, K.E.

    1977-01-01

    Uranium ore miners of the Colorado plateau suffer more than 6 times the normal incidence of lung cancer, and their mortality rates due to pneumoconiosis and emphysema are 5 times greater than in the general population. Inhalation exposures of beagle dogs and rodents to radon daughters and uranium ore dust were undertaken to determine which of these uranium mine air contaminants, and at what levels, are responsible for the high incidences of these diseases. Results are discussed

  10. Problems related to the carcinogenic impact of radon and daughters, as a source of exposure of population and underground miners

    International Nuclear Information System (INIS)

    Todorov, A.; Vasilev, G.; Vyrbanov, P.

    1998-01-01

    The population radiation exposure to radon and its daughters is a specific problem. In real conditions, ling irradiation in some population groups exceeds the allowable limit of occupational exposure for A category, but no increase in carcinogenesis is observed. At the same time, a correlation between dose and incidence of lung cancer is recorded in underground miners. There are various explanations of these effects, but a number of questions are still disputable. Thus in ICRP publication 60, for evaluation of radon irradiation exposure expressed in WLM is used, rather than effective dose. Epidemiological data are published, questioning the use of the linear non-threshold model for the carcinogenic impact of radon, as well as the role of some accompanying factors, such as smoking (author)

  11. Local energy deposited for alpha particles emitted from inhaled radon daughters

    International Nuclear Information System (INIS)

    Al-affan, I.A.M.; Haque, A.K.M.M.

    1989-01-01

    An analytical method has been developed to calculate the local energy deposited by alpha particles emitted from radon daughters deposited on the mucus surface in the lung airways. For the particular case of 218 Po (Ra A) and 214 Bi (Ra C'), microdose spectra have been evaluated in test spheres of 1 μm diameter which were taken to lie within airways of diameters 18 000, 3500 and 600 μm. In each case, the contributions of the near and far wall were computed separately. The average microdosimetric parameters y-bar F and y-bar D have also been calculated. For the two smaller airways, y-bar F and y-bar D values were found to be about 110 and 135 keV μm -1 for 218 Po and about 87 and 107 keV μm -1 for 214 Bi respectively. The corresponding values were about 10% higher for the largest airway. (author)

  12. House characteristics associated with gamma radiation and radon daughter working levels in eastern Pennsylvania

    International Nuclear Information System (INIS)

    Stebbings, J.H.; Dignam, J.J.; Reilly, M.A.; Gerusky, T.M.; Hartman, T.T.; Anast, G.A.

    1987-01-01

    Working levels (WL) of radon daughters and γ measurements in basements are described for ∼1200 houses near the Reading Prong. House variables studied included condition and construction materials of basement floors and walls, basement heights and areas, heating systems, air conditioning, water supply, and presence of drains and sump pumps. WL's were poorly predicted by house characteristics or γ measurements, while γ levels were well predicted by house characteristics and WL. Except for windowless basements, associated with both high γ andl high WL measurements, factors predicting high γ levels tended to be associated with low WL's and vice versa. Dirt basement floors and fieldstone basement walls were strongly associated with high γ levels, as were poor wall conditions in multivariate analyses. Gamma levels were low in electrically heated homes. High WL's were strongly associated with electric heat, low WL's with basement walls of fieldstone and/or in poor condition. Large house volumes and well water supply were also associated with higher WL's. 4 refs., 1 fig., 4 tabs

  13. Reliability of up-to-date risk factor between residential radon and lung cancer

    International Nuclear Information System (INIS)

    Tokonami, Shinji; Ishikawa, Tetsuo; Sorimachi, Atsuyuki; Kobayashi, Yosuke; Yoshinaga, Shinji; Quanfu, Sun; Akiba, Suminori

    2008-01-01

    Full text: The WHO launched an international radon project in January, 2005 because two major scientific articles on the residential-radon-and-lung-cancer risk have been published. Furthermore, the ICRP has just issued a new recommendation (Publ. 103). In the publication, radon issues have been mentioned using these references. They show that there is a significant correlation between radon exposures and lung cancer risks even with a somewhat lower radon concentration than an internationally recommended level (200 Bq m -3 ). In most cases, residential radon concentrations were measured by passive integrating radon monitors based on the alpha track detection techniques in their studies. We examined detection responses for the presence of thoron with some typical alpha track detectors (Kf K: Germany, Radtrak: USA and NRPB: UK), which were widely used in many epidemiological studies. In addition, we measured indoor radon and thoron concentrations in cave dwellings in Gansu Province, China, in which the National Cancer Institute (NCI) conducted a large-scale epidemiological study. The NCI concluded that there was also a significant correlation between the two aforementioned parameters, which was a similar value to recently acceptable one. However, our results on radon concentrations were obviously different from them because there was much thoron in that area. The present study demonstrates whether these risk factors are really correct throughout our data or not. Tokonami (2005) has pointed out that some of popular alpha track detectors are sensitive to thoron ( 220 Rn). This finding implies that radon readings will be overestimated and consequently may lead to biased estimates of lung cancer risk. The present study describes thoron interference on accurate radon measurements from the viewpoint of both experimental studies and field experiences. (author)

  14. 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....

  15. Radon and its daughter products behaviour in the air of an underground tourist route in the former arsenic and gold mine in Zloty Stok (Sudety Mountains, SW Poland)

    International Nuclear Information System (INIS)

    Przylibski, Tadeusz Andrzej

    2001-01-01

    This paper describes the occurrence of radon and its daughter products in the accessible workings, partially open to the public, in the former arsenic and gold mine in Zloty Stok. The geology of the area and the characteristics of the workings provide the background for explanation of the genesis of radon and its daughter products and of the spatial and temporal variations in their concentrations. The results demonstrate that well-ventilated areas along the tourist route have the lowest values of all the measured parameters and that temporal variations of these parameters are irregular. The highest concentration values for radon (up to 18.50 kBq/m 3 ) and its daughter products (up to 14.49 kBq/m 3 ) have been recorded in the workings with obstructed natural ventilation. These are the areas where seasonal oscillations in the concentrations of these isotopes have been registered, with the maxima in summer and the minima in winter. These sections of the workings are inaccessible to the casual visitor. Radon is supplied to the workings from the side walls and its concentration is influenced, most of all, by ventilation and the degree of rock fissuring. The reason is the uniform and not very high content of 226 Ra in the rocks where the galleries were excavated. Only locally, in the workings of the Gertruda adit lying outside the tourist route, do open fault zones have significant influence on enhanced concentrations of radon and its daughter products. These fault zones constitute effective routes of radon migration to the workings. In spite of this, it must be stated that neither guides nor tourists are exposed to excessive concentrations of radon or its daughter products in the tourist route area. However, the extension of the route to other workings will require the introduction of forced ventilation in order to lower the concentration of radon and its daughter products

  16. 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

  17. A new instrument for quick determination of radon and radon-daughter concentrations in air. Concept, analytical basis, calibration, caveats, the embodiment and field results

    International Nuclear Information System (INIS)

    Shreve, J.D. Jr.; Miller, R.W.; Cleveland, J.E.

    1977-01-01

    A new technique for measuring the radiation exposure hazard associated with radon daughters has been developed over a three-year period by Kerr McGee Nuclear Corporation. General physical configurations of the instrument were field evaluated and redesigned for maximum utility and user convenience in an underground mining situation. The principle of operation is based on the observation that the sum of ALPHA and BETA activity of a radon daughter sample collected on a particulate filter is a slowly vrying constant over a wide range of air 'age' and radon gas concentrations. The model 811 Instant Working Level Meter can provide a working level readout directly in 3 1/2 minutes after the start of air sampling as opposed to the 30-90 minutes necessary when using the other available techniques. The model 811 weighs 11 pounds, has digital LED readout directly in working level, can be used to estimate gamma exposure, and is operated by Ni Cad rechargeable batteries capable of providing 40 working level determinations in an 8 hour period. The working level measurements can be used together with a nomograph to calculate the approximate 'age of air' and to estimate the concentration of radon gas that produced the sample. A comparison and analysis of results obtained using the 811 and the Kusnetz and Tsivoglou methods both in the field and the laboratory, indicates the Instant Working Level Meter provides comparable data in about one-tenth the time. The economics and capacity for greater protection will be discussed as well as operating mechanics and principles

  18. 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)

  19. Comparison of radon-daughter exposures calculated for US- underground uranium miners based on MSHA and company records

    International Nuclear Information System (INIS)

    Cooper, W.E.

    1981-01-01

    How accurate are past and present employee radon-daughter exposure records of underground uranium miners employed in the United States. This often-debated question is essential for future substantiation of safe exposure limits. An apparent discrepancy between company-reported exposures and Mining Enforcement and Safety Administration (MESA) projected exposures was detected in 1977. For these reasons a need for an updated comparison of these exposure data was indicated. This paper gives some of the conclusions of the earlier study and compares more recent exposure records compiled by the Atomic Industrial Forum, Inc., with projected exposures based on sampling by Federal mine inspectors

  20. Proceedings of the specialist meeting on personal dosimetry and area monitoring suitable for radon and daughter products

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    The programme of work of the OECD Nuclear Energy Agency includes topics relating to radiation and environmental protection matters in mining and milling operations. A first Specialist Meeting on Personal Dosimetry and Area Monitoring suitable for Radon and Daughter Products was organised in October 1976 at Elliot Lake, Canada. The proceedings were published by NEA some months later. Following an enquiry among interested persons, NEA decided to organise a new meeting on the same subject in Paris from 20th to 22nd November 1978. The meeting dealt with questions relating to personal dosimetry techniques, the monitoring of the atmosphere in mines and their neighbourhood, as well as in buildings

  1. Protection of workers in radon-rich atmospheres: the mandate for quick determination of radon-daughter concentrations and a solution

    International Nuclear Information System (INIS)

    Shreve, J.D. Jr.

    1977-01-01

    The elementary observation of near-constancy of the sum of alpha and beta activity on a air sampling filter has led to a novel instrument. By exploiting this observation, a good working level determination can be made in a total time of 3.5 minutes. Second cycling and a total elapsed time of 7.5 minutes permits two determinations on the same filter, the second of which is more indifferent to daughter equilibration factors than either the 3.5 minute value or that defined by the Kusnetz method. This instrument and auxiliaries, designed by Kerr-McGee Corporation and licensed to MDA Scientific, Inc. for manufacturing and marketing, also permit estimates of external gamma radiation present at the uranium mine site, the equilibration factor of the radon daughters and the radon concentration itself. Its capacity to reduce exposure of underground workers via quicker detection and correction of high radiation areas is unmatched in a portable device. It has been found to at least double the efficiency of ventilation technicians. This sum of attributes is unobtainable in any other known instrument marketed in the world today

  2. Measurements of the radon-222 and its daughters concentrations throughout Gaza strip, Palestine

    International Nuclear Information System (INIS)

    Rasas, M.F.; Yassin, S.S.; Shabat, M.M.

    2005-01-01

    High Radon levels are present in the granite and grandiositic rocks that. spread in sand dunes along coast of Gaza. Such materials are rich in uranium and T widely used in the construction of dwelling in the Gaza, and their contribution to high indoor Radon levels is most relevant.The present work aims to investigate approaches, measures and detection of indoor Radon level throughout Gaza Strip. Five hundred CR-39 dosimeters were distributed over six locations in the middle Yv-region of Gaza Strip. Results suggest that Radon concentrations range from l3.36 to 83.82 Bq/m 3 and a maximum value of 97.01 Bq/m 3 .The average Radon concentrations was 37.83 Bq/m 3 with standard deviation of 11.23.The results provide a framework for future studies that include a large, broader survey of Radon concentration in Palestine

  3. Relation between residential radon concentrations and housing characteristics. The Cracow study

    International Nuclear Information System (INIS)

    Jedrychowski, W.; Flak, E.; Wesolowski, J.; Liu Kaishen

    1995-01-01

    The survey on indoor radon exposure was undertaken to explain whether the excess in lung cancer deaths in the Cracow city center may be attributed to this particular exposure. A total of 310 detectors was placed in households randomly chosen from three homogeneous strata of residential buildings. The first stratum included houses in the old city center constructed predominantly from stone bricks. The second stratum covered the city area with big apartment condominiums built from concrete blocks. The third stratum consisted of single family houses located in a suburban area. From each of these residency strata a random sample of an equal number of households was chosen, and the radon detectors were placed in households located at various levels of the buildings. The three-month radon sampling data were used to determine the distribution of various levels of radon in the households. In the measurement of radon exposure, Landauer α-track samplers were used. The data collected show that the type of building was the best single predictor of indoor radon concentrations. Other variables found to be associated significantly with indoor concentrations were the household level in the building and the house age. In general, residences with concrete slabs and dwellings with rarely-opened windows were found to have slightly higher radon concentrations. (author) 2 tabs., 15 refs

  4. Transport and deposition of nano-particles. Application to the free action of short-lived radon daughters

    International Nuclear Information System (INIS)

    Malet, J.

    1997-01-01

    Short-lived radon daughters ( 218 Po, 214 Pb, 214 Bi, and 214 Po) are important contributors to the natural average annual individual dose. The models describing the evolution of these aerosol in a house depend critically on a parameter, the 218 Po deposition velocity, which, although aerosol deposition has been extensively studied, is poorly known. A numerical and experimental study is thus carried out for a simple case: deposition in a cylindrical tube under laminar flow condition. The numerical results help understanding the difference between the transport and deposition of these radionuclides and those of non radioactive aerosols. Comparison of these well environment does not give satisfactory correlation, requiring the study of phenomena that may affect deposition. The first of these is the possible variation in the e 218 Po diffusion coefficient. Furthermore, experiments coupled with numerical calculations show that this variation could be due to 218 Po neutralization. The second phenomenon concerns the effect of the surface type, which is also shown experimentally. By modelling the neutralization and using results with a piratically smooth surface, good numerical/experimental correlations are obtained. Understanding this simple case than makes possible studying a more complex case: deposition in controlled turbulent flow. Two theories are thus experimentally validated. In addition, a 218 Po deposition velocity representative of our experimental conditions is determined. Finally, we report a feasibility study of radon daughters transport and deposition in a ventilated chamber taking into account all the involved phenomena. (author)

  5. Radon and its short-lived daughter products in the lower atmosphere; Le radon et ses derives a vie courte dans la basse atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Servant, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    The variations of vertical and temporal distributions of natural radioactivity with geographical location in the lower atmospheric layers are shown. The content of radon and its short lived daughters products are measured. Radon content is measured continually with a new apparatus, the sensibility of which is 0,2.10{sup -11} Ci m{sup -3} i.e. the fiftieth of the mean concentration near the soil, this apparatus allowed us to show that radioactive equilibrium between radon and its daughter products is realised when the atmosphere is stable. Air observations between 0 and 100 meters above the ground point out that radon and its decay products are valuable tracers to mark the stability of the atmosphere. Under very stable nighttime conditions the radon accumulates in the former 30 meters of the air layer, at sunrise it ascends and at 9 o'clock attains 100 meters high. The removal rate of the air in the lower atmosphere is computed from the movement of this radon mass, it is equal to 90 per cent for a summer day. We have show that this radon comes from the soil in which it diffuses by brownian motion the intensity of which varies with the water content of the soil, its value for June 1958 is 6,10{sup -17} Ci cm{sup -2}s{sup -1} and for January 1959 0.2,10{sup -17} Ci cm{sup -2} s{sup -}1. During the year 1958-1959 general mean of flux for the sedimentary soil studied is equal to 3. 8 {+-} 1.3, 10{sup -17} Ci cm{sup -2} s{sup -1} it is identical to the world wide mean computed by H. Israel. In a hilly site in the Morvan, air movements are well marked by this radioactivity. We observed from one hand downslope and up-slope breezes having, respectively, speeds of 0.2 m s{sup -1} and 0.7 m s{sup -1} and from the other hand by night, in the valley and with a light wind favours the stagnation of the air near the ground, a strong increase of the radioactivity which is proportional to the one of the granitic rocks of the region. The radon flux of this soil is 74,10{sup -17} Ci

  6. Report on the second international workshop on residential radon: Workshop proceedings

    International Nuclear Information System (INIS)

    1991-07-01

    As a follow-on to the first International Workshop on Residential Radon Epidemiology held in Alexandria VA, on July 24-26, 1989, a Second Workshop was convened, in Alexandria, VA, July 22-23 1991, also under the auspices of the US Department of Energy and the Commission of European Communities. The Workshop, co-chaired by Jonathan Samet and Jan Stolwijk, was attended by 20 active participants from seven countries representing epidemiologic studies recently completed, currently in progress, or in the last stages of preparation. The studies reported on are being conducted in the United States, Canada, Sweden, the United Kingdom, France, Belgium, Germany and the Peoples' Republic of China. The invited presentations that initiated the Workshop focused on a number of methodological problems that have surfaced in the last few years. Among these were: (1) the difficulties in predicting indoor radon concentrations, based on geologic information, (discussed by Alan Tanner, formerly of the US Geologic Survey); (2) the relationships between indoor radon concentrations and building characteristics (discussed by Richard Sextro, Lawrence Berkeley Laboratory, USA); (3) the approaches to analysis of case-control studies in radon epidemiology (discussed by Sarah Darby, Imperial Cancer Research Fund, UK); (4) statistical approaches to error in measurements and missing data (discussed by Donna Spiegelman, Tufts University, USA); (5) preliminary results of a data pooling effort dealing with several different studies of residential radon epidemiology and the lessons to be drawn from this effort (discussed by Jay Lubin, US National Cancer Institute)

  7. Appendix to radon and radon-daughter concentrations in air in the vicinity of the Anaconda Uranium Mill

    International Nuclear Information System (INIS)

    Momeni, M.H.; Lindstrom, J.B.; Dungey, C.E.; Kisieleski, W.E.

    1979-11-01

    Information is presented on the following subjects: site characteristics - stratigraphic description and water-bearing characteristics; meteorology - pooled observations made at two stations of windspeed, wind direction, and stability class; radon concentrations in air at various stations; and, frequencies of occurrence of given working levels at various stations

  8. Radon concentrations in residential housing in hiroshima and nagasaki

    International Nuclear Information System (INIS)

    Aoyama, Takashi; Radford, E.P.; Yonehara, Hidenori; Kato, Hiroo; Sakanoue, Masanobu.

    1993-05-01

    A survey of indoor radon ( 222 Rn) concentrations in Hiroshima and Nagasaki was carried out to assess the range of exposures expected among atomic-bomb survivors. Two hundred dwellings (100 from each city), chiefly of members of the Radiation Effects Research Foundation Life Span Study, were selected for this survey. We used two types of etched-track alpha-particle detectors: a Terradex detector (type SF) and an improved bare-track detector. Comparative measurements showed that although there was an adequate correlation between the values obtained using the two detectors, the geometric mean value for the bare-track detector was 45% lower than that for the Terradex detector. This difference was considered to be due to differences in the calibration methods and in the sensitivities of the detectors to thoron ( 220 Rn). The geometric mean values of the radon concentrations for 193 locations in Hiroshima and 192 locations in Nagasaki measured by Terradex SF detectors were 51.8 Bq/m 3 and 26.5 Bq/m 3 , respectively. The large difference is attributable to the different geological environments of the two cities. Factors correlating with the indoor radon concentrations were also studied. The geometric mean concentration was significantly higher in wooden houses with clay walls than in other types of house. This tendency was especially strong in Hiroshima. The difference between the estimated dose equivalents for exposure to radon decay products in dwellings in Hiroshima and Nagasaki during the last 30 years might amount to 0.8 Sv; however, no statistically significant difference was observed in lung-cancer mortality in the low-dose range in either city. Nevertheless, the indoor radon concentrations estimated in this survey could have a significant influence on the dose-response relationship for atomic-bomb exposure. (author)

  9. Study of the combined effects of smoking and inhalation of uranium ore dust, radon daughters and diesel oil exhaust fumes in hamsters and dogs. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Cross, F.T.; Palmer, R.F.; Filipy, R.E.; Busch, R.H.; Stuart, B.O.

    1978-09-01

    Exposure to particulates from uranium ore dust and diesel exhaust soot provoked inflammatory and proliferative responses in lungs. Also exposure to radon and radon daughters yielded increased occurrences of bronchiolar epithelial hyperplasia and metaplastic changes of alveolar epithelium. The data suggest that this cellular change is also a precursor of premalignant change in hamsters. The authors suggest an animal model other than the hamster based on two observations: (1) the Syrian golden hamster has been shown to be highly refractory to carcinoma induction; and (2) that when exposed to realistic levels of agents in life-span exposure regimens, the hamster does not develop lesions. Dog studies with cigarette smoke exposure showed mitigating effects on radon daughter induced respiratory tract cancer. Two reasons are suggested although no empirical evidence was gathered. A strict comparison of human and animal exposures and interpolative models are not possible at this time. (PCS)

  10. Residential radon and lung cancer: a cohort study in Galicia, Spain

    Directory of Open Access Journals (Sweden)

    Raquel Barbosa-Lorenzo

    Full Text Available Case-control studies show an association between residential radon and lung cancer. The aim of this paper is to investigate this association through a cohort study. We designed an ambispective cohort study using the Galician radon map, Spain, with controls drawn from a previous case-control study. Subjects were recruited between 2002 and 2009. The data were cross-checked to ascertain lung cancer incidence and then analysed using a Cox regression model. A total of 2,127 subjects participated; 24 lung cancer cases were identified; 76.6% of subjects were drawn from the radon map. The adjusted hazard ratio was 1.2 (95%CI: 0.5-2.8 for the category of subjects exposed to 50Bq/m3 or more. This risk rose when subjects from the case-control study were analyzed separately. In conclusion, we did not observe any statistically significant association between residential radon exposure and lung cancer; however, it appears that with a sample of greater median age (such as participants from the case-control study, the risk of lung cancer would have been higher.

  11. Asian/Australasian region intercalibration and intercomparison programme for radon, thoron and daughters. Asian/Australasian region radon intercomparison, September 1987 - September 1988

    Energy Technology Data Exchange (ETDEWEB)

    Peggie, J.R.; Gan, Tianghong; Solomon, S.B.

    1993-05-01

    The International Intercalibration and Intercomparison Programme for radon, thoron and daughters monitoring equipment, abbreviated IIIP, was a programme organized jointly by the Nuclear Energy Agency of the Organization for Economic Cooperation and Development and the Radiation Protection Research Programme of the Commission of European Communities. The broad purpose of the IIIP was to determine if the diverse calibration procedures used in different countries were equivalent. The general approach was to select four regional reference laboratories and entrust then with the details of project definition and execution. The Australian Radiation Laboratory (ARL) was selected to co-ordinate IIIP activities between OECD member countries in the Pacific region. As the regional programme precluded the participation of non-OECD member countries in the Western Pacific Region, an intercomparison series for radon was initiated by ARL in 1987 between twenty eight laboratories from nine countries in the Asian/Australasian region. The methodology and protocols for grab sampler, solid state nuclear track detectors (SSNTD) and charcoal measurements are described in this report. Generally the results showed reasonable agreement between the majority of laboratories for grab sampler measurements consistent with previous intercomparison. However there were large systematic differences in the results of the passive monitors for some laboratories. For all samplers, it was found that the overall random uncertainty or replication error, which included random uncertainties associated with the counting and calibration, were the main sources of variability between individual measurements of participants and the ARL reference value, with calibration uncertainties predominating. 23 tabs.

  12. Asian/Australasian region intercalibration and intercomparison programme for radon, thoron and daughters. Asian/Australasian region radon intercomparison, September 1987 - September 1988

    International Nuclear Information System (INIS)

    Peggie, J.R.; Gan, Tianghong; Solomon, S.B.

    1993-05-01

    The International Intercalibration and Intercomparison Programme for radon, thoron and daughters monitoring equipment, abbreviated IIIP, was a programme organized jointly by the Nuclear Energy Agency of the Organization for Economic Cooperation and Development and the Radiation Protection Research Programme of the Commission of European Communities. The broad purpose of the IIIP was to determine if the diverse calibration procedures used in different countries were equivalent. The general approach was to select four regional reference laboratories and entrust then with the details of project definition and execution. The Australian Radiation Laboratory (ARL) was selected to co-ordinate IIIP activities between OECD member countries in the Pacific region. As the regional programme precluded the participation of non-OECD member countries in the Western Pacific Region, an intercomparison series for radon was initiated by ARL in 1987 between twenty eight laboratories from nine countries in the Asian/Australasian region. The methodology and protocols for grab sampler, solid state nuclear track detectors (SSNTD) and charcoal measurements are described in this report. Generally the results showed reasonable agreement between the majority of laboratories for grab sampler measurements consistent with previous intercomparison. However there were large systematic differences in the results of the passive monitors for some laboratories. For all samplers, it was found that the overall random uncertainty or replication error, which included random uncertainties associated with the counting and calibration, were the main sources of variability between individual measurements of participants and the ARL reference value, with calibration uncertainties predominating. 23 tabs

  13. Procedure manual for the estimation of average indoor radon-daughter concentrations using the filtered alpha-track method

    International Nuclear Information System (INIS)

    George, J.L.

    1988-04-01

    One of the measurement needs of US Department of Energy (DOE) remedial action programs is the estimation of the annual-average indoor radon-daughter concentration (RDC) in structures. The filtered alpha-track method, using a 1-year exposure period, can be used to accomplish RDC estimations for the DOE remedial action programs. This manual describes the procedure used to obtain filtered alpha-track measurements to derive average RDC estimates from the measurrements. Appropriate quality-assurance and quality-control programs are also presented. The ''prompt'' alpha-track method of exposing monitors for 2 to 6 months during specific periods of the year is also briefly discussed in this manual. However, the prompt alpha-track method has been validated only for use in the Mesa County, Colorado, area. 3 refs., 3 figs

  14. Experimental determination of the unattached radon daughter fraction and dust size distribution in some Canadian uranium mines

    International Nuclear Information System (INIS)

    Bigu, J.; Kirk, J.

    1982-01-01

    The unattached radon daughter fraction has been experimentally determined in some Canadian uranium mines. Two experimental methods have been used, the wire screen method and a diffusion sampler based on Mercer's theory of diffusional deposition on parallel circular plates. Experiments were conducted in 'non-diesel' and 'diesel' areas of the mines, i.e. locations where mining was done with diesel machinery. Unattached fractions ranged from about 2-8 per cent for non-diesel area. For diesel areas the unattached fraction was substantially lower, less than about one per cent. The aerosol concentration in the range 0.0015 - 0.13 μm was measured with a condensation nuclei counter. Dust concentration was determined with conventional samplers. Particle size distribution in the respirable range was determined with a fine particle spectrometer in conjunction with eriometric techniques

  15. Studies on the diffusional and electrical transport of the daughter aerosols of radon and thoron in moving gases

    International Nuclear Information System (INIS)

    Mayya, Y.S.; Sahni, D.C.

    1994-01-01

    This report presents a detailed theoretical study of the transport characteristics of the daughter products of radon and thoron gases in channel flow devices. Specific aspects examined include: (i) development of the Green's function of the convective-diffusion operator and its boundary layer forms with and without axial diffusion, (ii) transport probabilities of recoil atoms (RaB) emitted into stagnant and moving gases, due to alpha decays of the parent atoms (RaA) deposited on surfaces, (iii) a comprehensive theory of double filter systems and (iv) microscopic theory of particle transport in moving fluids based on the Fokker-Planck equation. Both uniform and parabolic velocity profiles are considered. Various applications of the solutions in interpreting the measured data are presented. Chief among them is the application of the advanced theory of double-filter systems employed in Trombay studies for the measurements of thoron in the exhaled breath of thorium workers. (author). 130 refs., 4 figs

  16. Influence of radon-daughter exposure rate and uranium ore dust concentration on occurrence of lung tumors

    International Nuclear Information System (INIS)

    Cross, F.T.; Palmer, R.F.; Busch, R.H.

    1980-01-01

    Groups of male SPF Wistar rats were exposed concurrently to several levels of radon daughters and uranium ore dust to study the effect of these variables on pulmonary disease states. Clinical pathology data at 1 yr postexposure indicate no significant differences among exposed animals when compared with controls. Preliminary histopathologic data suggest a trend toward increasing lung tumor risk as the exposure rate is decreased (constant total dose), but the differences are not statistically significant at the 0.05 level. A similar trend occurs with decrease in ore dust concentration (except for the 2560-WLM exposure group), but these differences are also not significant at the 0.05 level. The tumor risk is significantly (0.05 level) increased as the exposure level increases from approximately 320 and 640 WLM to 2560 WLM at the high ore dust concentration

  17. Determination of radon daughter activities of different aerosol fractions by gross-α and gross-β measurements

    International Nuclear Information System (INIS)

    Katona, T.; Kanyar, B.; Jobbagy, V.; Kavasi, N.; Molnar, A.; Imre, K.

    2004-01-01

    The aim was to determine the radioactivities of the radon progenies ( 218 Po, 214 Pb, 214 Bi and 214 Po) attached to the carrier aerosol particles with respect to the size distribution in order to improve the assessment of the inhalation dose. We derived the radionuclide-specific activity concentrations from gross alpha and gross beta measurements provided during 2 hours after sampling and model calculations including parameter estimation. For the aerosol sampling we used an electrical low pressure impactor, which is able to collect aerosol particles in 12 different diameter ranges. In our test investigations the aerosol particles were collected from a closed chamber in a common laboratory building. The chamber contained a relatively high radon concentration (60-90 kBq/m 3 ) in equilibrium with the short lived daughters generated previously without any additional aerosol sources. For the nuclear measurements of the aerosol samples ZnS/plastic sandwich detectors have been used. The time series data of gross alpha and gross beta activities were fitted simultaneously and the initial activities of the daughters were estimated. According to the results from two different fractions (0.06 and 0.7 μm) just followed the end of sampling they contain a higher 218 Po activity than the 214 Pb and 214 Bi ones. The preliminary assessments for the special air conditions show that the 214 Pb-to- 218 Po activity ratios are higher for the small aerosol particles than for the larger ones. The estimated errors of the initial activities were near to 50% in a large part of cases. (author)

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

    International Nuclear Information System (INIS)

    Fabrikant, J.I.

    1982-06-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Fabrikant, J.I.

    1982-06-01

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

  20. The potential for bias in Cohen's ecological analysis of lung cancer and residential radon

    International Nuclear Information System (INIS)

    Lubin, Jay H.

    2002-01-01

    Cohen's ecological analysis of US lung cancer mortality rates and mean county radon concentration shows decreasing mortality rates with increasing radon concentration (Cohen 1995 Health Phys. 68 157-74). The results prompted his rejection of the linear-no-threshold (LNT) model for radon and lung cancer. Although several authors have demonstrated that risk patterns in ecological analyses provide no inferential value for assessment of risk to individuals, Cohen advances two arguments in a recent response to Darby and Doll (2000 J. Radiol. Prot. 20 221-2) who suggest Cohen's results are and will always be burdened by the ecological fallacy. Cohen asserts that the ecological fallacy does not apply when testing the LNT model, for which average exposure determines average risk, and that the influence of confounding factors is obviated by the use of large numbers of stratification variables. These assertions are erroneous. Average dose determines average risk only for models which are linear in all covariates, in which case ecological analyses are valid. However, lung cancer risk and radon exposure, while linear in the relative risk, are not linearly related to the scale of absolute risk, and thus Cohen's rejection of the LNT model is based on a false premise of linearity. In addition, it is demonstrated that the deleterious association for radon and lung cancer observed in residential and miner studies is consistent with negative trends from ecological studies, of the type described by Cohen. (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. EWLMII: a measurement and data-acquisition system for radon daughters

    Energy Technology Data Exchange (ETDEWEB)

    Keefe, D.J.; McDowell, W.P.; Groer, P.G.

    1981-01-01

    Development of new methods and instruments for the measurement of WL and Rn-daughter concentrations has been in progress for several years. However, efficient methods of data acquisition has not been the primary thrust of this research. If large volumes of data from automated instruments are to be efficiently analyzed, a built in data acquisition system is needed. One such instrument, the EWLMII, is described. The need for accelerated research for the understanding and control of Rn-daughters can be enhanced by such an instrument.

  4. EWLMII: a measurement and data-acquisition system for radon daughters

    International Nuclear Information System (INIS)

    Keefe, D.J.; McDowell, W.P.; Groer, P.G.

    1981-01-01

    Development of new methods and instruments for the measurement of WL and Rn-daughter concentrations has been in progress for several years. However, efficient methods of data acquisition has not been the primary thrust of this research. If large volumes of data from automated instruments are to be efficiently analyzed, a built in data acquisition system is needed. One such instrument, the EWLMII, is described. The need for accelerated research for the understanding and control of Rn-daughters can be enhanced by such an instrument

  5. The issue of radon and daughters in water and in air detection using the detection unit 'YAPMARE'

    International Nuclear Information System (INIS)

    Thinova, L.; Trojek, T.; Kunka, A.; Maly, P.; Blazek, K.; Notaristefani, F. de; Moucka, L.

    2004-01-01

    The specialized detection unit YAPMARE was developed by company CRYTUR Ltd. The main part of the detection unit is a detection probe based on a 100 mm x 25 mm diam. YAP:Ce detector, made of monocrystalline YAP:Ce (chemical formula is YAlO 3 doped Ce) grown by Crytur Ltd. YAP:Ce crystal advantages are in chemical resistance, good mechanical properties, nonhygroscopicity and ease of polishing; remainder of radionuclides deposited on the Teflon surface can be easily deactivated using HCl acid. The detection unit was developed for 222 Rn and its daughter's measurement in water under extreme conditions (pressure, temperature and acidity) to obtain additional information about flow dynamics in Earth crust. The detection volume for water (or air) is 12 ml and in this case the measured medium covers approximately 95% of the crystal surface, while the remaining 5% is a spiral groove machined into the Teflon enclosure (used as a reflector). Spectrometry results of the measurement are an advantage for data processing. The main points of 'YAPMARE' unit testing are as follows: Methodology of water sample collection, defining the optimum measurement time interval; Energetic stability monitoring; Gamma ray energetic calibration using etalons and natural radioactive rock; Alpha ray energetic calibration using dry (air) standards of 222 Rn and 220 Rn, with peaks in alpha spectrum identification; The gamma background elimination during measurement and in data processing; Measuring the high 222 Rn water activity (Svornost mine in Jachymov - radon activity 17 kBq/l); Probe calibration for radon-in-water determination (using fresh water from a drilled well in Lounovice near Prague and using a 222 Rn water standard). Due to the large crystal volume all measurements were conducted inside a Pb shield 25 mm thick. The water alpha activity was also monitored using radon monitor RADIM 4. All results of testing will be presented. (author)

  6. New Jersey's residential radon remediation program - methods and experience

    International Nuclear Information System (INIS)

    Pluta, T.A.; Cosolita, F.J.; Rothfuss, E.

    1986-01-01

    As part of a remedial action program to decontaminate over 200 residential properties, 12 typical properties were selected and a demonstration program was initiated in the spring of 1985. The residences selected represented a range of contamination levels and configurations and differing architectural styles representative of the age of construction. The physical limitations of the sites and the overall nature of a decontamination project in active residential communities imposed a number of severe restrictions on work methods and equipment. Regulations governing transportation and disposal set virtually zero defect standards for the condition of containers. The intrusive nature of the work in residential neighborhoods required continual interaction with local residents, public officials and citizen task forces. Media coverage was very high. Numerous briefings were held to allay fears and promote public understanding. Numerous issues ranging in content from public health and safety to engineering and construction methods arose during the remedial action program. These issues were resolved by a multi-disciplined management team which was knowledgeable in public administration, radiation physics, and engineering design and construction. This paper discusses the nature of the problem, the methods applied to resolve the problem and the experience gained as a result of a remedial action program

  7. Disturbance from Am-241 Photons of the Cellular Dose by Am-241 Alpha Emissions: Am-241 as an alternative source of alpha particles to radon daughters

    International Nuclear Information System (INIS)

    Lee, Ki-Man; Kim, Eun-Hee

    2015-01-01

    The Radiation Bioengineering Laboratory (RadBio Lab) at Seoul National University (SNU) has built an Am-241 alpha particle irradiator for study of cellular responses to radiation from radon daughters. The radon daughters of concern that cause internal exposure from inhalation of radon-contaminated air are Po-218, Po-214 and Po-210. In their alpha decay schemes, the yields of photon emissions are negligible. Unfortunately, Am-241, the source of alpha irradiator in RadBio Lab, emits photons at every alpha decay while transforming to Np-237 of long half-life. Employing Am-241 as the source simulating radon daughters, therefore, requires that photon emissions from Am-241 be specified in term of dose contribution. In this study, Monte Carlo calculations have been made to characterize dose contributions of Am-241 photon emissions. This study confirms that disturbance from Am-241 photon emissions of the cellular dose by Am-241 alpha emissions is negligible. Dose contamination fraction from photon emissions was 8.02 .. 10 -6 at 25 mm SSD at maximum. Also, note that LET in tissue-equivalent medium varies within about 20% for alpha particles at energies over 5 MeV

  8. Environmental dosimetry of radon-222 and daughters: measurement of absolute calibration factors of CR-39 considering the plate-out effects and environmental factors

    International Nuclear Information System (INIS)

    Paulo, S.R. de.

    1991-08-01

    The subject of this work concerns with the measurement of absolute calibration factors for the use of CR-39 as an absolute detector in indoor and daughters monitoring. Up to now the usefulness of calibration factors was restricted to environmental conditions equal (or very close) to those worthing during their determinations. This fact is consequence of the difficulties related to the understanding of the plate-out properties of radon daughters activity in the air. The plate-out effects on radon daughters monitoring performed by SSNTDs are studied. Our experimental results are in agreement with those of other authors about the great sensitivity of CR-39 to the plate-out effects, fact that recommended its use in this work. Being succeeded in the employment of CR-39 as an alpha-spectrometer we concluded that some important information (like the radon daughters deposition rates on the walls of an environment) can be achieved. The knowledge about the behavior of plate-out made possible the determination of the ranges in zenithal angle and energy where CR-39 can detect alpha-particles with efficiency of 100%, at our conditions of track observation. In this way, we obtained calibration factors for CR-39 that are weakly dependent on environmental conditions. We think that these results can contribute to the improvement of RD (Radiation Detector) detection techniques. (author). 159 refs, 106 figs, 05 tabs

  9. Determination of detection efficiency for radon and radon daughters with CR 39 track detector - a Monte Carlo study

    International Nuclear Information System (INIS)

    Nikezic, D.

    1994-01-01

    The detection effciency, ρ, (or a calibration coefficient k) for radon measurements with a solid state nuclear track detector CR 39 was determined by many authors. There is a considerable discrepancy among reported values for ρ. This situation was a challenge to develop a software program to calculation ρ. This software is based on Bethe-Bloch's expression for the stopping power for heavy charged particles in a medium, as wll as on the Monte Carlo Method. Track parameters were calculated by using an iterative procedure as given in G. Somogyi et al., Nucl. Instr. and Meth. 109 (1973) 211. Results for an open detector and for the detector in a diffusion chamber were presented in this article. (orig.)

  10. Radon Measurements in Vojvodina

    International Nuclear Information System (INIS)

    Bikit, I.; Bikit, K.; Forkapic, S.; Mrda, D.; Nikolov, J.; Todorovic, N.; Veskovic, M.

    2013-01-01

    Recent analyses of epidemiological studies of lung cancer risk from residential exposures demonstrate a statistically significant increase per unit of exposure below average annual concentrations of about 200 Bq/m 3 . Indoor radon measurements performed in Novi Sad in about 400 houses and flats are presented and discussed in this paper. By measuring gamma-activity of radon daughters, radon activity concentration was determined to be 50 Bq/m 3 . In Vojvodina region indoor radon levels were measured by alpha track detectors CR-39 on about 3000 locations during the winter seasons in the period of three years (2003-2005). The main aim of the present study was to explore the critical group of population for radon exposure and to estimate maximal annual doses. Existing radon maps which identify regions with elevated radon levels will improve data collection and analysis for the future radon campaigns. Collaboration on the JRC program of European indoor radon map and implementation of grid system are also discussed.(author)

  11. Radiation burden in dwelling-houses by Radon and its daughter elements

    International Nuclear Information System (INIS)

    Hofmann, W.

    1982-01-01

    The content of 222 Rn and its short-lived decay products in room air shows large local as well as temporal fluctuations. The local differences are caused mainly by the concentration of 226 Ra in building materials and the exhalation of radon from the walls. Temporal variations result from varying ventilation conditions and changing meteorological parameters. The influence of all these factors on the natural radiation burden of man is discussed. (Author) [de

  12. Internal irradiation by radon daughters in Bulgarian uranium mines over the period 1956-1990

    International Nuclear Information System (INIS)

    Dimitrov, M.; Presiyanov, D.

    1993-01-01

    The results of over 30-years' radiation monitoring in Bulgarian uranium mines are summed up in retrospect. The overall organization and the parameters monitored during the different periods are discussed. A radiological characteristic of the working environment is presented which includes radon and its decay products. The internal irradiation levels during different time periods and in different mines have been estimated. The health costs of uranium mining in Bulgaria are discussed and conclusions and recommendations for radiological control are made. (author)

  13. Development of electret technology to measure indoor radon-daughter concentrations: Final report (Phase 1)

    International Nuclear Information System (INIS)

    Kotrappa, P.; Dempsey, J.C.; Stieff, L.R.

    1989-05-01

    A new type of radon progeny monitor called an electret radon progeny integrating sampling unit (E-RPISU) was developed and demonstrated which uses an electret ion chamber to measure the progeny concentration. A conventional 1 LPM particulate air sampling system is used to collect the progeny on a 35 cm 2 filter which is mounted on the side of the electret ion chamber such that the collected progeny are exposed to the inside of the chamber. The alpha radiation emitted by the progeny collected on the filter ionizes the air in the 220 ml chamber. The ions of opposite polarity collect on the surface of the 127 μm thick electret and reduce its surface voltage. A specially built surface voltmeter is used to measure the electret voltage before and after sampling. The electret voltage drop which occurs during the sampling period is shown to be proportional to the time integrated progeny concentration. Two prototype systems were fabricated and tested in homes and in calibrated radon chambers. The resulting data are presented and analyzed. The calibration factor for the E-RPISU ranged from 1.5 to 2.0 V/mWL-day depending on the electret voltage. Two of the E-RPISUs were delivered to UNC Geotech for further testing. 32 refs., 11 figs., 5 tabs

  14. Stochastic model of radon daughter deposition and clearance in human bronchial airways

    International Nuclear Information System (INIS)

    Hofmann, W.

    1996-01-01

    Morphometric measurements of human airway casts have repealed that the human bronchial tree is an asymmetrically dividing network, exhibiting individual variations of airway dimensions within a given airway generation Thus, a statistical correlation exists between the linear dimensions of a given parent airway and those of the asymmetrically dividing daughter branches. This statistical relationship, however, is constrained by correlations among various geometrical parameters. i.e., the human lung is not a fully stochastic system. From a statistical analysis of these morphometric data, the following geometrical parameters could be obtained for each airway generation or bifurcation: (i) probability distributions for diameters and lengths, ratios of parent cross section to the combined cross section of both daughters, ratios of major to minor daughter diameters, and branching angles for major and minor branches; (ii) correlations of diameters and lengths; and (iii) the probability of terminating the bronchial region as a function of both diameter and generation number. Since the original lung morphometry refers to total lung capacity, airway diameters and lengths were scaled down to functional residual capacity. (author)

  15. Internal irradiation with radon daughters in some Bulgarian polymetal mines over the period 1962-1993

    International Nuclear Information System (INIS)

    Presiyanov, D.; Dimotrov, M.

    1993-01-01

    The results of radiation monitoring of the working environment in the Bulgarian metal mines are evaluated. The irradiation levels in the Burgas Copper Mines and their variations over the years have been estimated. A radiological characteristic of the working environment is provided together with a risk assessment for workers in different mines. A retrospective risk assessment is attempted for mines where increased radon 222 levels have been detected recently. The organization of radiometric monitoring and measures to limit the risk of internal irradiation are discussed. (author)

  16. Residential radon exposure, diet and lung cancer: a case-control study in a Mediterranean region.

    Science.gov (United States)

    Bochicchio, Francesco; Forastiere, Francesco; Farchi, Sara; Quarto, Maria; Axelson, Olav

    2005-05-10

    We performed a case-control study in Lazio, a region in central Italy characterized by high levels of indoor radon, Mediterranean climate and diet. Cases (384) and controls (404) aged 35-90 years were recruited in the hospital. Detailed information regarding smoking, diet and other risk factors were collected by direct interview. Residential history during the 30-year period ending 5 years before enrollment was ascertained. In each dwelling, radon detectors were placed in both the main bedroom and the living room for 2 consecutive 6-month periods. We computed odds ratios (ORs) and 95% confidence intervals (CIs) for time-weighted radon concentrations using both categorical and continuous unconditional logistic regression analysis and adjusting for smoking, diet and other variables. Radon measurements were available from 89% and 91% of the time period for cases and controls, respectively. The adjusted ORs were 1.30 (1.03-1.64), 1.48 (1.08-2.02), 1.49 (0.82-2.71) and 2.89 (0.45-18.6) for 50-99, 100-199, 200-399 and 400+ Bq/m(3), respectively, compared with 0-49 Bq/m(3) (OR = 1; 0.56-1.79). The excess odds ratio (EOR) per 100 Bq/m(3) was 0.14 (-0.11, 0.46) for all subjects, 0.24 (-0.09, 0.70) for subjects with complete radon measurements and 0.30 (-0.08, 0.82) for subjects who had lived in 1 or 2 dwellings. There was a tendency of higher risk estimates among subjects with low-medium consumption of dietary antioxidants (EOR = 0.32; -0.19, 1.16) and for adenocarcinoma, small cell and epidermoid cancers. This study indicates an association, although generally not statistically significant, between residential radon and lung cancer with both categorical and continuous analyses. Subjects with presumably lower uncertainty in the exposure assessment showed a higher risk. Dietary antioxidants may act as an effect modifier.

  17. A radon (thoron) daughter personal alpha-dosimeter of the passive type using a diffused-junction detector and an electrostatic collector

    International Nuclear Information System (INIS)

    Bigu, J.; Frattini, A.

    1984-05-01

    A solid-state alpha-dosimeter has been designed and found to be suitable for personal and environmental radon-thoron daughter monitoring. The dosimeter basically consists of an electrostatic collector and an alpha-particle counting system with spectroscopy capabilities. The sensitive volume (∼20 cm 3 ) of the electrostatic collector consists of a cylindrically-shaped metal wire screen and a diffused-junction silicon alpha-detector covered with a thin aluminized mylar sheet. A DC voltage (∼450 V) is applied between the wire screen and the mylar sheet, the latter held at negative potential relative to the metal screen. Data can be retrieved during or after sampling by means of a micro-computer (Epson HX20) via a RS-232 communcation interface unit. The dosimeter has been calibrated in a large (26 m 3 ) radon/thoron test facility. A linear relationship was found between radon gas concentration and radon daughter Working Level, and the dosimeter's alpha-count. The dosimeter is mounted on top of an ordinary miner's cap lamp battery and is ideally suited for personal monitoring in underground uranium mines and other working areas. The dosimeter presented here is a considerably improved version of an earlier prototype

  18. 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 ...

  19. Measurements of seasonal and daily radon daughter concentration fluctuations in National Park Service caves

    International Nuclear Information System (INIS)

    Yarborough, K.A.

    1977-01-01

    The National Park Service (NPS) is studying levels of airborne alpha radiation from radon and thoron in all NPS administered caves in which tours for visitors are regularly conducted. The NPS research has the dual but complementary objectives of safeguarding health at the NPS administered caves, and to develop data on alpha radiation levels and on natural airflows in NPS caves. The results reported here for NPS caves describe concepts hypothesized for the objectives. In addition the data can be used by various agencies to clarify health standards for exposures to low airborne alpha radiation levels in cave environments. These results show daily and seasonal trends and the influence of natural ventilation by air circulation for each cave investigated

  20. Radon and its daughter products behaviour in the air of an underground tourist route in the former arsenic and gold mine in Złoty Stok (Sudety Mountains, SW Poland).

    Science.gov (United States)

    Przylibski, T A

    2001-01-01

    This paper describes the occurrence of radon and its daughter products in the accessible workings, partially open to the public, in the former arsenic and gold mine in Zloty Stok. The geology of the area and the characteristics of the workings provide the background for explanation of the genesis of radon and its daughter products and of the spatial and temporal variations in their concentrations. The results demonstrate that well-ventilated areas along the tourist route have the lowest values of all the measured parameters and that temporal variations of these parameters are irregular. The highest concentration values for radon (up to 18.50kBq/m3) and its daughter products (up to 14.49kBq/m3) have been recorded in the workings with obstructed natural ventilation. These are the areas where seasonal oscillations in the concentrations of these isotopes have been registered, with the maxima in summer and the minima in winter. These sections of the workings are inaccessible to the casual visitor. Radon is supplied to the workings from the side walls and its concentration is influenced, most of all, by ventilation and the degree of rock fissuring. The reason is the uniform and not very high content of 226Ra in the rocks where the galleries were excavated. Only locally, in the workings of the Gertruda adit lying outside the tourist route, do open fault zones have significant influence on enhanced concentrations of radon and its daughter products. These fault zones constitute effective routes of radon migration to the workings. In spite of this, it must be stated that neither guides nor tourists are exposed to excessive concentrations of radon or its daughter products in the tourist route area. However, the extension of the route to other workings will require the introduction of forced ventilation in order to lower theconcentration of radon and its daughter products. reserved.

  1. Chromosomal aberrations of blood lymphocytes induced in vitro by radon-222 daughter α-irradiation

    International Nuclear Information System (INIS)

    Pohl-Rueling, J.; Lettner, H.; Hofmann, W.; Atzmueller, C; Eckl, P.; Haas, O.A.; Obe, G.; Grell-Buechtmann, I.; Van Buul, P.P.W.; Natarajan, A.T.; Schroeder-Kurth, T.; Sasaki, M.S.; Fischer, P.; Kubiak, R.

    2000-01-01

    Blood samples were irradiated in vitro with α-rays emitted from short-lived radon decay products dissolved in the culture medium at doses between 0.03 and 41.4 mGy. The data were collected from experiments conducted during the period 1984-1992 and comprise a total of about 64000 scored metaphases. For statistical reasons, only 60,022 metaphases were used for the subsequent analysis. The results for total chromosome aberrations and dicentrics indicate a linear dose dependence in the dose range above about 10 mGy, consistent with other experimental observations. At doses below about 10 mGy, aberration frequencies cannot be linearly extrapolated from higher doses, suggesting that there is no dependence on dose within a certain low-dose range. In addition, a statistically significant minimum has been observed at a dose of about 0.03 mGy, which is consistently lower than the related control values. The behavior of the aberration frequencies in the low-dose region seems to be influenced by the control values, which also depend on the environmental radiation burdens to the donors before blood sampling and thus were significantly affected by the Chernobyl fallout

  2. Uncertainty in exposure of underground miners to radon daughters and the effect of uncertainty on risk estimates

    International Nuclear Information System (INIS)

    1989-10-01

    Studies of underground miners provide the principal basis for assessing the risk from radon daughter exposure. An important problem in all epidemiological studies of underground miners is the reliability of the estimates of the miners' exposures. This study examines the various sources of uncertainty in exposure estimation for the principal epidemiologic studies reported in the literature including the temporal and spatial variability of radon sources and, with the passage of time, changes to both mining methods and ventilation conditions. Uncertainties about work histories and the role of other hard rock mining experience are also discussed. The report also describes two statistical approaches, both based on Bayesian methods, by which the effects on the estimated risk coefficient of uncertainty in exposure (WLM) can be examined. One approach requires only an estimate of the cumulative WLM exposure of a group of miners, an estimate of the number of (excess) lung cancers potentially attributable to that exposure, and a specification of the uncertainty about the cumulative exposure of the group. The second approach is based on a linear regression model which incorporates errors (uncertainty) in the independent variable (WLM) and allows the dependent variable (cases) to be Poisson distributed. The method permits the calculation of marginal probability distributions for either slope (risk coefficient) or intercept. The regression model approach is applied to several published data sets from epidemiological studies of miners. Specific results are provided for each data set and apparent differences in risk coefficients are discussed. The studies of U.S. uranium miners, Ontario uranium miners and Czechoslovakian uranium miners are argued to provide the best basis for risk estimation at this time. In general terms, none of the analyses performed are inconsistent with a linear exposure-effect relation. Based on analyses of the overall miner groups, the most likely ranges

  3. Estimating the risk of lung cancer from inhalation of radon daughters indoors: review and evaluation. Final report, October 1986-April 1988

    International Nuclear Information System (INIS)

    Borak, T.B.; Johnson, J.A.

    1988-06-01

    A review of the dosimetric models and epidemiological studies with regard to the relation between indoor radon exposure and lung cancer indicates that the Working Level is an appropriate unit for indoor radon exposure; that the uncertainty in applying risk estimates derived from uranium miner data may be reduced by determining nose vs. mouth breathing ratios, residential aerosol characteristics, and lung cancer risk vs. age at exposure; that there is persuasive evidence of an association between radon exposure indoors and lung cancer; and that epidemiological studies in progress may provide a basis for revision or validation of current models but only is experimental designs are employed that will permit pooling of data to obtain greater statistical power

  4. A survey of the concentration of radon and its daughters in air of the dugouts in three cities of Changsha, Hengyang and Zhuzhou

    International Nuclear Information System (INIS)

    Liu Hanqin; Xian Renyi; Zeng Xinyuan

    1986-01-01

    The concentrations of radon and its daughters in air of the dugouts was reported. This survey was made in three cities of Changsha, Hengyang and Zhuzhou. In dugouts which are used for cultivation of mushrooms (category I) or which have been reconstructed as hotels and the places for recreation (category II), the average concentration of radon and its daughter were found to be 0.451 Bq/l (12.2 pCi/l) and 0.872 μJ/m 3 (0.0419 WL) in Changsha, 0.710 Bq/l (19.2 pCi/l) and 1.47 μJ/m 3 (0.0709 WL) in Hengyang and 0.236 Bq/l (6.39 pCi/l) and 0.418 μJ/m 3 (0.0201 WL) in Zhuzhou, respectively. However, in those dugouts which have been reconstructed as the places for recreation the averange concentration of radon and its daughters were obtained to 0.566 Bq/l (15.3 pCi/l) and 0.940 μJ/m 3 (0.0452 WL) in Changsha, 1.10 Bq/l (29.8 pCi/l) and 2.83 μJ/m 3 (0.136 WL) in Hengyang and 0.511 Bq/l (13.8 pCi/l) and 0.982 μJ/m 3 (0.0472 WL) in Zhuzhou. For γ-rays, the range of exposure rate was 6-22 μR/h with a mean of 12 μR/h. The effective dose equivalent for persons working in these dugouts was estimated and some measures for radiation protection were suggested

  5. 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)

  6. Method of determining the variation of concentration of the potential alpha energy of radon daughters with time without changing the filter

    International Nuclear Information System (INIS)

    Feddersen, C.

    1979-01-01

    Considering the drawbacks of sample measurement of radon daughter concentration or potential alpha energy concentration, a method is described allowing to determine the variation with time of the measuring quantities mentioned. For this purpose, the same filter is exposed in defined time intervals and the decay curve is evaluated using Markov's method. Residual activity of preceding measurements is estimated as a function of the density of measuring points. A practicable technique is given for taking into account residual activity together with the background. An apparatus consisting of commercial devices and special accessories of own manufacture is described. The results obtained with this apparatus are illustrated and discussed using two examples. (author)

  7. 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.

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

    International Nuclear Information System (INIS)

    Weinberg, C.R.

    1995-01-01

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

  9. Transport and deposition of nano-particles. Application to the free action of short-lived radon daughters; Transport et depot des aerosols nanometriques. Application a la fraction libre des descendants a vie courte du radon

    Energy Technology Data Exchange (ETDEWEB)

    Malet, J

    1997-10-10

    Short-lived radon daughters ({sup 218}Po, {sup 214}Pb, {sup 214}Bi, and {sup 214}Po) are important contributors to the natural average annual individual dose. The models describing the evolution of these aerosol in a house depend critically on a parameter, the {sup 218}Po deposition velocity, which, although aerosol deposition has been extensively studied, is poorly known. A numerical and experimental study is thus carried out for a simple case: deposition in a cylindrical tube under laminar flow condition. The numerical results help understanding the difference between the transport and deposition of these radionuclides and those of non radioactive aerosols. Comparison of these well environment does not give satisfactory correlation, requiring the study of phenomena that may affect deposition. The first of these is the possible variation in the e {sup 218}Po diffusion coefficient. Furthermore, experiments coupled with numerical calculations show that this variation could be due to {sup 218}Po neutralization. The second phenomenon concerns the effect of the surface type, which is also shown experimentally. By modelling the neutralization and using results with a piratically smooth surface, good numerical/experimental correlations are obtained. Understanding this simple case than makes possible studying a more complex case: deposition in controlled turbulent flow. Two theories are thus experimentally validated. In addition, a {sup 218}Po deposition velocity representative of our experimental conditions is determined. Finally, we report a feasibility study of radon daughters transport and deposition in a ventilated chamber taking into account all the involved phenomena. (author)

  10. Preliminary results regarding the first map of residential radon in some regions in Romania

    International Nuclear Information System (INIS)

    Cosma, C.; Cucos Dinu, A.; Dicu, T.

    2013-01-01

    Radon represents the most important contribution of population exposure to natural ionising radiation. This article presents the first indoor radon map in some regions of Romania based on 883 surveyed buildings in the Stei-Baita radon-prone region and 864 in other regions of Romania. Indoor radon measurements were performed in the last 10 y by using CR-39 nuclear track detectors exposed for 3-12 months on ground floor levels of dwellings. Excluding the Stei-Baita radon-prone region, an average indoor radon concentration of 126 Bq m -3 was calculated for Romanian houses. In the Stei-Baita radon-prone area, the average indoor concentration was 292 Bq m -3 . About 21 % of the investigated dwellings in the Stei-Baita radon-prone region exceed the threshold of 400 Bq m -3 , while 5 % of the dwellings in other areas of Romania exceed the same threshold. As expected, indoor radon concentration is not uniformly distributed throughout Romania. The map shows a high variability among surveyed regions, mainly due to the differences in geology. The radon emanation rate is substantially influenced by the soil characteristics, such as the soil permeability and soil gas radon concentration. Since higher permeability enables the increased migration of soil gas and radon from the soil into the building, elevated levels of indoor radon can be expected in more permeable soil environments. (authors)

  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. 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…

  13. Relationship of radioactive radon daughters and cigarette smoking in the genesis of lung cancer in uranium miners

    International Nuclear Information System (INIS)

    Saccomanno, G.; Huth, G.C.; Auerbach, O.; Kuschner, M.

    1988-01-01

    This article documents the study of 383 cases of lung cancer in uranium miners and presents for the first time the relationship of radioactive radon gas and cigarette smoking. There is evidence that alpha radiation from radon gas at exposure levels above 465 working level months (WLM) is a strong contributor to the development of lung cancer. Cigarette smoking plays the most significant role in causing lung tumor; this is also noticed in nonminers who smoke cigarettes. A synergistic or additive effect of these two carcinogens is strongly suggested. The data indicate that small cell tumors develop in younger nonsmoking miners exposed to radon levels above 465 WLM. Lung cancers develop in smoking miners at lower levels of radon exposure than in nonsmoking miners. Based on an average mining experience of 15 years, there is substantial evidence that the present maximum allowable limit of 0.3 working levels (WL), or 4 working level months (WLM) per year, is safe, representing a margin of safety of approximately 10:1. Furthermore, a comparison of these data with the radon levels in some homes, averaging in the neighborhood of 0.025 WL, would indicate that health risks at these levels are negligible. It is suggested that 20 picocuries/liter, which equals 0.10 WL, be the maximum allowable level in homes

  14. 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

  15. The possible role of indoor radon reduction systems in back-drafting residential combustion appliances

    International Nuclear Information System (INIS)

    Henschel, D.B.

    1997-01-01

    A computational sensitivity analysis was conducted to identify the conditions under which residential active soil depressurization (ASD) systems for indoor radon reduction might most likely exacerbate or create back-drafting of natural-draft combustion appliances. Parameters varied included: house size; normalized leakage area; exhaust rate of exhaust appliances other than the ASD system; and the amount of house air exhausted by the ASD system. Even with a reasonably conservative set of assumptions, it is predicted that ASD systems should not exacerbate or create back- drafting in most of the U.S. housing stock. Only at normalized leakage areas lower than 3 to 4 cm 2 commercial at 4 Pa) per m 2 of floor area should ASD contribute to back-drafting, even in small houses at high ASD exhaust rates (compared to a mean of over 10 cm 2 /m 2 determined from data on over 12,000 U.S. houses). But on the other hand, even with a more forgiving set of assumptions, it is predicted that ASD systems could contribute to back-drafting in some fraction of the housing stock -houses tighter than about 1 to 2 cm 2 /m 2 - even in large houses at minimal ASD exhaust rates. It is not possible to use parameters such as house size or ASD system flow rate to estimate reliably the risk that an ASD system might contribute to back-drafting in a given house. Spillage/back-draft testing would be needed for essentially all installations. (au) 18 refs

  16. Methodology for determination of radon-222 production rate of residential building and experimental verification

    International Nuclear Information System (INIS)

    Tung, Thomas C.W.; Niu, J.L.; Burnett, J.; Lau, Judy O.W.

    2005-01-01

    Indoor radon concentration is mainly associated with the radon production rate of building material, ventilation rate, and the outdoor radon concentrations. Radon production rate of a room is defined as the sum of the products of the radon emanation rates and the exposed areas of the materials. Since the selection of the building materials and the exposed areas are different from room to room, it makes the radon production rate of homes fall in a wide range. Here, the radon production rate of a room is suggested to be quantified by a sealing method, in which the systematic radon growth curve is obtained. The radon production rate of the room can be determined from the initial slope of the growth curve. Three rooms at different homes in Hong Kong were selected in the study for verifying the methodology. The uncertainty characterized by data scatter arisen from the coupling effect of the leakage rate and outdoor radon was also included in the discussion. During the measurements, no occupant was allowed into the home. No mechanical ventilation was involved in the measurement. The indoor and outdoor radon concentrations of the sampled homes were monitored simultaneously and lasted for more than three days. The radon production rates and the uncertainties of three rooms at Homes 1, 2, and 3 were found to be 232.8, 46.0, 414.6, and 20.3, 9.4, 59.2Bqh -1 , respectively. The approach is valid when the air leakage rate of the room is controlled below 0.1h -1

  17. Setting the Scene for a Healthier Indoor Living Environment: Citizens’ Knowledge, Awareness, and Habits Related to Residential Radon Exposure in Romania

    Directory of Open Access Journals (Sweden)

    Dacinia Crina Petrescu

    2017-11-01

    Full Text Available The present research is based on the premise that people perceive radiation risks in different ways, depending on their cultural background, information exposure, economic level, and educational status, which are specific to each country. The main objective was to assess and report, for the first time, the Romanians’ attitude (perceptions, knowledge, and behaviors related to residential radon, in order to contribute to the creation of a healthier living environment. A convenience sample of 229 people from different parts of Romania, including radon prone areas, was used. Results profiled a population vulnerable to radon threats from the perspective of their awareness and perceptions. Thus, study results showed that most participants did not perceive the risk generated by radon exposure as significant to their health; only 13.1% of interviewed people considered the danger to their health as “high” or “very high”. Additionally, it was found that awareness of radon itself was low: 62.4% of the sample did not know what radon was. From a practical perspective, the study shows that in Romania, increasing awareness, through the provision of valid information, should be a major objective of strategies that aim to reduce radon exposure. The present study takes a bottom-up perspective by assessing Romanian citizens’ attitudes toward radon. Therefore, it compensates for a gap in the behavioral studies literature by providing practical support for radon risk mitigation and creating the premises for a healthier living environment.

  18. Residential radon in Kansas City-black shales aren't the prime suspect

    International Nuclear Information System (INIS)

    Spencer, C.G.

    1993-01-01

    The US EPA preliminary assessment of potential radon risk (EPA, 1986) depicted a large area of the mid-continent in which radon levels might be elevated due to the presence of uranium-rich black shales. A preliminary study (Hilpman, Coveney ampersand Spencer, 1988) indicated that a significant percentage of homes in the greater Kansas City area had radon screening levels above 4 pCi/L. However, their lab tests with crushed black shale, and radon tests in limestone mines with black shale floors showed that the shale did not yield extremely high radon levels. This expanded study presents additional results of screening tests in homes, and correlates those results to bedrock geology and soil type. High radon levels in the Kansas city area are not due primarily to black shale sources. The highest readings are associated with limestone and non-organic shale. Mean radon level is higher in younger cyclothemic deposits, and a loessial soil. The EPA initial assessment overstated the radon risk attributable to black uraniferous shale sources. Assessment of the overall potential risk for the greater Kansas City area requires further evaluation of other sources

  19. Quantitative evaluation of the lung cancer deaths attributable to residential radon: A simple method and results for all the 21 Italian Regions

    International Nuclear Information System (INIS)

    Bochicchio, F.; Antignani, S.; Venoso, G.; Forastiere, F.

    2013-01-01

    Pooled analyses of epidemiological case-control studies on lung cancer and residential radon have shown that radon exposure in dwellings increases lung cancer risk, and that the increase is statistically significant also for prolonged exposures to low-medium level of radon concentration, i.e. levels commonly found in many dwellings. In this paper, a simple method to evaluate the health burden due to the presence of radon in homes (i.e. the number of lung cancer deaths attributable to radon exposure in dwellings) was presented. This method is based on the following parameters: i) the excess relative risk per unit of exposure evaluated in case-control studies; ii) the average radon concentration that can be considered representative of population exposure in dwellings; iii) the total number of lung cancer deaths occurring each year. Moreover, the interaction between radon and cigarette smoking is needed to be taken into account: in fact, although most of the persons are non-smokers, most of the lung cancer deaths attributed to radon are actually due to the multiplicative effect of radon and cigarette smoking. To show this effect, the number of radon related lung cancer deaths estimated to occur among current, former and never smokers was calculated separately for males and females, taking into account the relative risk of lung cancer for the different smoking categories and the prevalence of smoking habits. The methodology described in this work was applied to all the 21 Italian Regions in order to illustrate it. The overall fraction of lung cancer deaths attributable to radon in Italy is about 10%, with values in individual Regions ranging from 4% to 16%. The greater part of the lung cancers attributable to radon is estimated to occur among current smokers for both males and females (72% and 60%, respectively, at national level). This is due to the synergistic effects of radon and cigarette smoking, which should therefore be taken into account in policies aimed to

  20. Emission of radon from soil

    International Nuclear Information System (INIS)

    Ahlberg, P.; Lindmark, A.; Rosen, B.

    1980-03-01

    The report deals with the measurement of radon daughters in the soil Radon migrates readily through the limestone which is superpositioned the alum shale. The level of gamma radiation is normal. Measurements have been made by the track etch technique and with Kodak film. The contents of radon daughters are shown to be due to the measuring depth. (G.B.)

  1. Lung cancer risks from residential radon among smokers and non-smokers

    International Nuclear Information System (INIS)

    Enflo, Anita

    2002-01-01

    Primary lung cancer occurs mainly among elderly smokers. Smoking and radon are generally considered to be the main causes of lung cancer. By simply studying the age dependence of all primary lung cancer incidences it seems plausible to suggest that the risk for obtaining lung cancer from domestic radon is low for children. In addition, as there are few non-smoking primary lung cancer cases at older ages, it seems plausible to suggest that most of the radon-induced lung cancer cases are to be found among the smoking population. Reduction of smoking habits would appear to be the most cost effective method to reduce lung cancer cases. (author)

  2. Preliminary assessment of errors of radon daughters concentration in air; Wstepna ocena bledow miernika koncentracji produktow rozpadu radonu w powietrzu

    Energy Technology Data Exchange (ETDEWEB)

    Machaj, B. [Institute of Nuclear Chemistry and Technology, Warsaw (Poland)

    1996-12-31

    Employing an earlier elaborated computer program for simulation of depositing radon decay products: {sup 214}Po, {sup 214}Pb, {sup 214}Bi ({sup 214}Po) on air filter and for computing variation of their activity against time, an assessment of errors was carried out of a methods employing measurement of {sup 218}Po + {sup 214}Po alpha activity in three time intervals. Additionally errors of the methods measuring {sup 218}Po + {sup 214}Po alpha activity in three, two and one time intervals, were assessed. A few attempts were also made to measure the alpha activity in different time intervals and to assess their measuring errors. (authors). 10 refs, 4 figs, 14 tabs.

  3. Evaluation of thoron-daughter instruments

    International Nuclear Information System (INIS)

    George, J.L.

    1992-09-01

    Several DOE decontamination and decommissioning sites need to accurately measure thoron-daughter concentrations during decontamination efforts. Because the workers at these sites receive their dose from thoron-daughters rather than thoron gas, the thoron-daughter concentration is the measurement of interest. Some instruments currently used for making radon-daughter concentration measurements also claim the ability to measure thoron-daughter concentrations. This study evaluated the validity of those claims

  4. Radon and daughters in cigarette smoke measured with SSNTD and corresponding committed equivalent dose to respiratory tract

    International Nuclear Information System (INIS)

    Misdaq, M.A.; Flata, K.

    2003-01-01

    Uranium ( 238 U) and Thorium ( 232 Th) contents were measured inside various tobacco samples by using a method based on determining detection efficiencies of the CR-39 and LR-115 II solid state nuclear track detector (SSNTD) for the emitted alpha particles. Alpha and beta activities per unit volume, due to radon ( 222 Rn), thoron ( 220 Rn) and their decay products, were evaluated inside cigarette smokes of tobacco samples studied. Annual committed equivalent doses due to short-lived radon decay products from the inhalation of various cigarette smokes were determined in the thoracic and extrathoracic regions of the respiratory tract. Three types of cigarettes made in Morocco of black tobacco show higher annual committed equivalent doses in the extrathoracic and thoracic regions of the respiratory tract than the other studied cigarettes (except one type of cigarettes made in France of yellow tobacco); their corresponding annual committed equivalent dose ratios are larger than 1.8. Measured annual committed equivalent doses ranged from 1.8x10 -9 to 1.10x10 -3 Sv yr -1 in the extrathoracic region and from 1.3x10 -10 to 7.6x10 -6 Sv yr -1 in the thoracic region of the respiratory tract for a smoker consuming 20 cigarettes a day

  5. Radon in dwellings

    International Nuclear Information System (INIS)

    Erikson, B.E.; Boman, C.A.; Nyblom, L.; Swedjemark, G.A.

    1980-06-01

    The report presents the function of the ventilation by natural draught in three-storey houses. In some cases also the measurement of gamma radiation, radon and radon daughters was made. The investigation took place in Uppsala. The houses were built of light weight concrete made of alum-shale. The measurements showed that the contents of radon daughters were far below the provisional limits. (G.B.)

  6. Prediction of residential radon exposure of the whole Swiss population: comparison of model-based predictions with measurement-based predictions.

    Science.gov (United States)

    Hauri, D D; Huss, A; Zimmermann, F; Kuehni, C E; Röösli, M

    2013-10-01

    Radon plays an important role for human exposure to natural sources of ionizing radiation. The aim of this article is to compare two approaches to estimate mean radon exposure in the Swiss population: model-based predictions at individual level and measurement-based predictions based on measurements aggregated at municipality level. A nationwide model was used to predict radon levels in each household and for each individual based on the corresponding tectonic unit, building age, building type, soil texture, degree of urbanization, and floor. Measurement-based predictions were carried out within a health impact assessment on residential radon and lung cancer. Mean measured radon levels were corrected for the average floor distribution and weighted with population size of each municipality. Model-based predictions yielded a mean radon exposure of the Swiss population of 84.1 Bq/m(3) . Measurement-based predictions yielded an average exposure of 78 Bq/m(3) . This study demonstrates that the model- and the measurement-based predictions provided similar results. The advantage of the measurement-based approach is its simplicity, which is sufficient for assessing exposure distribution in a population. The model-based approach allows predicting radon levels at specific sites, which is needed in an epidemiological study, and the results do not depend on how the measurement sites have been selected. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Measurement of concentrations of radon and its daughters in indoor atmosphere using CR-39 nuclear track detector

    International Nuclear Information System (INIS)

    Farid, S.M.

    1993-01-01

    This paper presents the results of the measurements of indoor 222 Rn and daughter levels in houses of different types located in different parts of Bangladesh. The passive time-integrated method of using a solid state nuclear track detector (CR-39) was employed for measuring both the 222 Rn gas concentration as well as the potential alpha energy exposure (PAEE) level from the short lived daughters of 222 Rn. The 222 Rn concentration from cup exposure and the PAEE from the bare exposure were obtained directly from the track density using calibration curves. A total of 275 exposures were made in the bare mode in 15 locations and 71 exposures in the cup mode in 6 locations. The geometric mean PAEE level obtained is 9.5 mWL with a geometric standard deviation of 1.9. The corresponding value for 222 Rn concentration are 61.3 Bq.M -3 and 2.4. The total data was collected over a period of one and a half year. The monthly variation of the geometric mean of PAEE is also shown. The annual effective dose equivalent has been estimated for each location by using the conversion factor of 9 mWv per WLM as obtained from ICRP-50. The average PAEE level obtained from the total data is below the intervention level as suggested by US EPA. However, the individual averages for each location show that in 8 out of 15 locations intervention may be considered and in others not intervention is called for. The 222 Rn concentrations at the seven locations are equal or less than the equilibrium equivalent 222 Rn concentration value as suggested by EPA. Attempts have also been made to see the variation in the PAEE levels according to different type of construction material used for the houses. (Author)

  8. Radon decay product in-door behaviour - parameter, measurement method, and model review

    International Nuclear Information System (INIS)

    Scofield, P.

    1988-01-01

    This report reviews parameters used to characterize indoor radon daughter behavior and concentrations. Certain parameters that affect indoor radon daughter concentrations are described and the values obtained experimentally or theoretically are summarized. Radon daughter measurement methods are reviewed, such as, PAEC, unattached daughters, particle size distributions, and plateout measurement methods. In addition, certain radon pressure driven/diffusion models and indoor radon daughter models are briefly described. (orig.)

  9. Distribution pattern of radon and daughters in an urban environment and determination of organ-dose frequency distributions

    International Nuclear Information System (INIS)

    Steinhaeusler, F.; Hofmann, W.; Pohl, E.; Pohl-Rueling, J.

    1980-01-01

    In a normal urban environment, inhaled radon and its decay products cause an important part of the human radiation burden not only for the respiratory tract but also for several other organs. A study was made with 729 test persons in Salzburg, Austria. Each person was questioned regarding his living activity, i.e., the mean times he spent in individual sleeping, living, and working places and the corresponding physical activities that strongly influence the respiratory minute volume and consequently the inhaled radioactivity. At all these places, the annual means of the external gamma radiation as well as of the air content of 222 Rn and its short-lived decay products were determined. From all these measurements (more than 8000) and the information obtained, mean annual organ doses were calculated for each test person. The doses due to cosmic radiation, 40 K, and other radionuclides incorporated were totaled. The range of the mean annual doses in millirems is only from 73 to 126 for gonads and 70 to 336 for the kidneys and finally reaches from 117 to 10,700 for the basal cells of the bronchial epithelium

  10. Study of lung cancer and residential radon in the Czech Republic

    International Nuclear Information System (INIS)

    Tomasek, L.; Mueller, T.; Kunz, E.; Heribanova, A.; Matzner, J.; Placek, V.; Burian, I.; Holecek, J.

    2001-01-01

    The lung cancer mortality study was designed as a follow-up study of the population (N = 12,004) in a radon-prone area in the Czech Republic, covering the 1960-1999 period. Information on the vital status and causes of death was mostly obtained from local authorities and extracted from the national population registry. Exposure estimates were based on one-year measurements of radon progeny in the majority of houses within the study area (74 %). Exposures outside the area (16%) were based on radon mapping of the Czech Republic. The mean concentration, 509 Bq/m 3 , is five-fold higher than the country-wide average. By 1999, a total of 210 lung cancers had been observed, which is somewhat more than the nationally expected value (O/E = 1.10), as compared to the generally low numbers regarding cancer types other than lung cancer (O/E = 0.81). The excess relative risk for the standard radon concentration (100 Bq/m 3 ) was 0.087 (90 % CI: 0.017-0.208), which is consistent with the risk coefficients derived from other indoor studies. The increased lung cancer incidence was found to depend linearly on exposure in terms of the mean radon concentration during the past 5-34 years. The estimate was not affected appreciably by adjustment to smoking; although the risk coefficient was higher for non-smokers than for smokers (0.130 vs 0.069), the difference was not statistically significant

  11. Measurements of radon in residential buildings in Maryland and Pennsylvania, U.S.A

    International Nuclear Information System (INIS)

    George, A.C.; Duncan, M.; Franklin, H.

    1984-01-01

    Radon concentrations were measured in six all-electric and 31 randomly selected homes in Pennslyvania, and 41 homes in Maryland. The measurements were made in the basements and living areas of each home using integrating passive activated carbon detectors for an exposure period of about 3 days. The average concentration varied substantially among the homes and correlated well with the age of the home, the degree of insulation, and ventilation. On average, concentrations in the living areas were lower than those in the basements. Radon levels in the living areas of a substantial number of homes (39% in Pennslyvania, excluding the six all-electric homes, and 51% in Maryland) were greater than or equal to 3 pCi.1 -1 , resulting in a substantial annual absorbed dose to the bronchial epithelial cells of the occupants of the homes. (author)

  12. Radon dynamics in underwater thermal radon therapy

    International Nuclear Information System (INIS)

    Lettner, H.; Hofmann, W.; Winkler, R.; Rolle, R.; Foisner, W.

    1998-01-01

    At a facility for underwater thermal radon therapy in Bad Hofgastein, experiments were carried out with the aim of establishing radon in the air exhaled by the treated patients and of radon decay products on the skin of the patients. The time course of radon concentration in the exhaled air shows a maximum a few minutes after entering the bath, then the Rn concentration remains constant over the remaining time spent in the bath. Taking into account several simplifying assumptions, the average dose to the epidermis from radon daughters is about 50 μGy. (A.K.)

  13. Radon and thoron monitoring in the environment of Kumaun Himalayas: survey and outcomes

    International Nuclear Information System (INIS)

    Ramola, R.C.; Negi, M.S.; Choubey, V.M.

    2005-01-01

    Monitoring of radon, thoron and their daughter products was carried out in houses of Kumaun Himalaya, India using LR-115 plastic track detectors. The measurements were made in residential houses from June 1999 to May 2000 at a height of 2.5 m from ground level using a twin chamber radon dosimeter. The twin chamber radon dosimeter can record the values of radon, thoron and their decay products separately. Maximum and minimum indoor radon and thoron concentrations were evaluated and activity concentrations of radon and thoron daughters were estimated. The resulting dose rates due to radon, thoron and their decay products varied from 0.04 to 1.89 μSv/h. A detailed analysis of the distribution of radon, thoron and their decay products inside the house is also reported. The observed dose rates inside the houses of Kumaun Himalaya were found to be lower than the ICRP recommended value of 200 Bq/m 3 and thus are within safe limits

  14. The Pennsylvania radon story

    International Nuclear Information System (INIS)

    Gerusky, T.M.

    1987-01-01

    In December 1984, the Pennsylvania Bureau of Radiation Protection found itself confronted with the discovery of a home in eastern Pennsylvania having the highest level of radon daughters ever reported. The Bureau responded with a massive radon monitoring, educational, and remediation effort. As of November, 1986, over 18,000 homes had been screen for radon daughters, of which approximately 59% were found to have levels in excess of the 0.020 Working Level guideline. Pennsylvania's response to the indoor radon problem is detailed in this article

  15. Mortality of a residential cohort exposed to radon from industrially contaminated soil

    International Nuclear Information System (INIS)

    Klotz, J.B.; Petix, J.R.; Zagraniski, R.T.

    1989-01-01

    A historical cohort mortality study was conducted in three neighborhoods of Essex County, New Jersey, to investigate the mortality patterns of persons who had inhabited 45 homes documented to be contaminated by radon gas emanating from radium processing waste. Residency history and vital status were collected for 752 persons, comprising 91% of the subjects enumerated who had resided in the index homes for at least one year during the years 1923-1983. Standardized mortality ratios (SMR) were used to compare the death rates of the study group with the death rates of the United States and New Jersey. While there were no statistically significant excesses of lung cancer for the cohort or its subgroups, an elevated mortality rate for lung cancer was found for white males in the comparison of lung cancer mortality rates in the United States (SMR = 1.5, 95% confidence interval (CI) 0.7-2.7) and New Jersey (SMR = 1.7, 95% CI 0.8-3.2). No excess of lung cancer was observed in females or nonwhites. The small size of the cohort and the inability to collect smoking histories or complete occupational data limited the study. Nevertheless, the degree of excess lung cancer among white males was in agreement with both the attributable and relative risk estimates per unit of exposure derived for radon from mining studies

  16. Lung cancer mortality (1950-80) in relation to radon daughter exposure in a cohort of workers at the Eldorado Port Radium uranium mine: possible modification of risk by exposure rate

    International Nuclear Information System (INIS)

    Howe, G.R.; Nair, R.C.; Newcombe, H.B.; Miller, A.B.; Burch, J.D.; Abbatt, J.D.

    1987-01-01

    A cohort study of 2103 workers employed between 1942 and 1960 at a uranium mine in the Northwest Territories, Canada, was conducted. A total of 57 lung cancer deaths was observed (expected = 24.73, P less than .0001). There was a highly significant linear relationship between exposure and increased risk of lung cancer, giving estimates for the relative and attributable risk coefficients of 0.27 per working level month (WLM) and 3.10 per WLM per 10(6) person-years. These risk coefficients were substantially less than those estimated from the experience of miners in the Beaverlodge mine, which have previously been reported. Any biases in the present estimates are likely to have been upward, and therefore they probably represent an upper limit. The major difference between the two mine cohorts is in the exposure rate, since the Port Radium miners were exposed to much greater concentrations of radon daughters than the Beaverlodge miners. It is postulated that risk of lung cancer from radon daughter exposure may be modified by exposure rate, for which hypothesis there is some support from other epidemiologic data

  17. 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

  18. Distribution of 210-Po and 210-Bi Radon Daughters in the Brain Proteins of a Subject who Suffered from Alzheimer's Disease

    International Nuclear Information System (INIS)

    Momcilovic, B.; Lykken, G. I.

    2003-01-01

    Alzheimer Disease (AD), the most common cause of dementia in the elderly, is a progressive neurodegenerative disorder of unknown origin that gradually robs the patient of cognitive function and eventually causes death. Recently, we showed that radon daughters selectively accrue in both the gray and white brain matter proteins in AD. There, we proposed that AD is the systemic disease of the brain cells involving the cell membrane protein structures of ion gates, pores and channels, with the consequent chlorine leaking into the cells and fall of the cell membrane gradient. The quoted studies were performed on the cortex and subcortex of the frontal and temporal human brain lobe and, therefore, the aim of this case report is to further investigate the distribution of radon daughters in the brain of an AD subject. The respective radioactivity of 2 10P o and 2 10B i accumulated in the frontal and temporal lobe of this subject is in a close agreement with that of the group of subjects who suffered from AD and what we reported earlier. That fact allows us to assume with the great deal of certainty that the distribution of RAD in the other studied brain structures is reliable in this single subject case report. Hippocampus has been long considered to be an essential part of so called Papez circle involved in the memory process of the brain. Therefor, considering our previous report that RAD accumulate in the brain proteins in AD, their high accumulation in the hippocampus was somewhat anticipated. Hippocampus was shown to be the seat of generation of new brain cells, the type of specific nerve cells, which occur in the three out of six cell layers of the brain cortex. Interestingly enough, the RAD in Hippocampus are about two times higher than that in the brain cortext what indicates the intriguing possibility that these three common layers in these two different brain structures may have some identical features. Nucleus Amygdala, an anatomical structure close anterior and

  19. EML indoor radon workshop, 1982

    International Nuclear Information System (INIS)

    George, A.C.; Lowder, W.; Fisenne, I.; Knutson, E.O.; Hinchliffe, L.

    1983-07-01

    A workshop on indoor radon, held at the Environmental Measurements Laboratory (EML) on November 30 and December 1, 1982, covered recent developments in radon daughter research and development. Thirty papers were presented dealing with standardization and quality assurance measurement methods, surveys, measurements strategy, physical mechanisms of radon and radon daughter transport and development of guidance standards for indoor exposures. The workshop concluded with a planning session that identified the following needs: (1) national and international intercomparisons of techniques for measuring radon and radon daughter concentrations, working level and radon exhalation flux density; (2) development and refinement of practical measurement techniques for thoron and its daughter products; (3) quantitative definition of the sources of indoor radon and the mechanisms of transport into structures; (4) better knowledge of the physical properties of radon daughters; (5) more complete and accurate data on the population exposure to radon, which can only be met by broadly based surveys; and (6) more international cooperation and information exchange among countries with major research programs

  20. Radon as a hydrological indicator

    Energy Technology Data Exchange (ETDEWEB)

    Komae, Takami [National Research Inst. of Agricultural Engineering, Tsukuba, Ibaraki (Japan)

    1997-02-01

    The radon concentration in water is measured by a liquid scintillation method. After the radioactive equilibrium between radon and the daughter nuclides was attained, the radon concentration was determined by the liquid scintillation analyzer. {alpha}-ray from radon, then two {beta}- and two {alpha}-ray from the daughter nuclei group were released, so that 500% of the apparent counting efficiency was obtained. The detector limit is about 0.03 Bq/l, the low value, which corresponds to about 5.4x10{sup -15} ppm. By determining the radon concentration in groundwater, behavior of radon in hydrological process, the groundwater exchange caused by pumping and exchange between river water and groundwater were investigated. The water circulation analysis by means of radon indicator in the environment was shown. By using the large difference of radon concentration between in river water and in groundwater, arrival of injected water to the sampling point of groundwater was detected. (S.Y.)

  1. Public radiation exposure due to radon transport from a uranium mine

    International Nuclear Information System (INIS)

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

    1992-01-01

    Radon and radon daughter concentrations at locations several kilometres away from a uranium mine are due both to the background sources and the mine-related sources. The contribution of these two types of sources should be distinguished because the authorised limits on public radiation dose apply only to the mine-related sources. Such a distinction can be achieved by measuring radon and radon daughter concentration in the wind sectors containing only the background sources and those in the wind sectors containing both the background and the mine-related sources. This approach has been used to make estimates of public radiation dose due to radon transport from the Ranger Uranium Mine in Australia. The residential town of Jabiru, the non-residential working town of Jabiru East, and the aboriginal camp sites in the vicinity of the mine were considered. The results indicate that, for the groups of population considered, the annual mine-related dose varies between 0.04 and 0.2 mSv. (author)

  2. Radon diffusion chamber

    International Nuclear Information System (INIS)

    Pretzsch, G.; Boerner, E.; Lehmann, R.; Sarenio, O.

    1986-01-01

    The invention relates to the detection of radioactive gases emitting alpha particles like radon, thoron and their alpha-decaying daughters by means of a diffusion chamber with a passive detector, preferably with a solid state track detector. In the chamber above and towards the detector there is a single metallized electret with negative polarity. The distance between electret and detector corresponds to the range of the alpha particles of radon daughters in air at the most. The electret collects the positively charged daughters and functions as surface source. The electret increases the sensitivity by the factor 4

  3. A field method for monitoring thoron-daughter working level

    International Nuclear Information System (INIS)

    Khan, A.H.; Dhandayatham, R.; Raghavayya, M.; Nambiar, P.P.V.J.

    1975-01-01

    The concept of working level, generally used for radon daughters, has been extended to the daughter products of thoron. Accordingly, thorondaughter working level (TWL) has been defined as the alpha energy released from the ultimate decay of 100 pCi/1 each of the short-lived decay products of thoron. In order to facilitate the evaluation of inhalation hazard in thorium handling areas, a simple field method has been suggested to measure the thoron-daughter working level. A comparison of the potential alpha energies from radon-daughters and that from thoron-daughter is included. (K.B.)

  4. Environmental dosimetry of radon-222 and daughters: measurement of absolute calibration factors of CR-39 considering the plate-out effects and environmental factors; Dosimetria ambiental de Rn-222 e filhos: medida da eficiencia absoluta do CR-39 levando-se em conta os efeitos do plate-out e fatores ambientais

    Energy Technology Data Exchange (ETDEWEB)

    Paulo, S.R. de

    1991-08-01

    The subject of this work concerns with the measurement of absolute calibration factors for the use of CR-39 as an absolute detector in indoor and daughters monitoring. Up to now the usefulness of calibration factors was restricted to environmental conditions equal (or very close) to those worthing during their determinations. This fact is consequence of the difficulties related to the understanding of the plate-out properties of radon daughters activity in the air. The plate-out effects on radon daughters monitoring performed by SSNTDs are studied. Our experimental results are in agreement with those of other authors about the great sensitivity of CR-39 to the plate-out effects, fact that recommended its use in this work. Being succeeded in the employment of CR-39 as an alpha-spectrometer we concluded that some important information (like the radon daughters deposition rates on the walls of an environment) can be achieved. The knowledge about the behavior of plate-out made possible the determination of the ranges in zenithal angle and energy where CR-39 can detect alpha-particles with efficiency of 100%, at our conditions of track observation. In this way, we obtained calibration factors for CR-39 that are weakly dependent on environmental conditions. We think that these results can contribute to the improvement of RD (Radiation Detector) detection techniques. (author). 159 refs, 106 figs, 05 tabs.

  5. Radon measurements in Ghana: health risk assesment at the Lake Bosomtwi basin

    International Nuclear Information System (INIS)

    Andam, A.A.B.; Addison, E.C.K.; Nani, E.K.; Amankwah, E.A.

    2007-01-01

    The need to assess the risk of exposure to radon and its daughters stems from the reality, that radon is a potential carcinogenic. We report Radon-222 risk assessment, from measurements on soil and sediments taken from six towns along the Lake Bosomtwi basin at two levels of 10cm and 20cm. The current and future prospects of Lake Bosomtwi, the largest natural lake in Ghana, make this assessment imperative, since radon forms half of natural background radiation. Spatial Analyser Decision Assistant (SADA) algorithms were used to model the measured radon concentrations under two land-use scenarios, namely residential and recreational. Setting the data under a targeted risk of 1E-6,we found that the external exposure was below that of the maximum concentrations to the measurements. This indicates that the radon levels around those towns as of the time of the measurements is low and below limits which can cause carcinogenic threats. The mean risk associated with the sampled locations was found to be 9E-11 at the recreational areas and 2E-8 at residential centres. To confirm the authenticity of the point risk analysis, geospatial modelling based on inverse distance interpolation schemes were performed. The results tally closely with that of the measured point risk analysis with and error margin of 2% and 1.3 % for both land use scenarios at 10 cm and 20 cm depth respectively. (au)

  6. Evaluation of a Po-210 bioassay as an index of the exposure of uranium mine workers in Japan to radon daughters

    International Nuclear Information System (INIS)

    Okabayashi, Hiroyuki; Suzuki, Masashi; Hongo, Shozo; Watanabe, Seiki.

    1975-01-01

    As an indicator nuclide for inhalation exposure of mine workders to Rn daughters in a Japanses uranium mine, 210 Po urinalyses of the workers and surveys of some environmental factors were conducted. An estimation study of concentrations of Rn daughters in a mine, indicated that about 800-50 pCi of 210 Po could have been accumulated in each miner's body. However, according to the results of urinalyses performed several times in 5 years, a statistical difference in the quantity of 210 Po in urine among miners and non-mining workers there was not clearly identified. Investigations of 210 Po concentrations in the mine's air, water, foods (of about 30 kinds) and cigarets, and investigations of feces-urine 210 Po ratios in humans revealed that these factors would greatly affect the metabolism and 210 Po excretion of the workers. In particular, some marine foods in Japan contained a great amount of 210 Po (several hundreds times that of other foods) and cigarets showed 0.3-0.8 pCi of 210 Po per gramme. Smokers definitely excreted more 210 Po in urine than non-smokers. Feces-urine ratios ranged between 5.2-42.9 in one human subject. Therefore, it can be concluded that 210 Po would not be a good indicator for human exposure to Rn daughters, unless great care is taken regarding the eating and smoking habits of mine workers, as well as the exposure conditions in the uranium mine. (Evans, J.)

  7. The risks from radon in homes

    International Nuclear Information System (INIS)

    Duggan, M.J.

    1990-01-01

    A report has been proposed by a Working group of the Institute of Radiation Protection on the risks from radon in homes. The report includes a historical perspective, properties and behavior of radon and its daughters, measurement of radon exposure in UK homes, remedial action, quantification of the risk and lifetime risks from other causes. (UK)

  8. Radon surveys and their implications

    International Nuclear Information System (INIS)

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

    1989-01-01

    In the UK, as in other countries, radon daughter inhalation is the most significant cause of human exposure to ionising radiation either at home or at work whether one considers the mean or the maximum dose. Substantial studies of radon are under way in the UK, and the importance of radon is recognised in several spheres. NRPB investigations of the radon levels in buildings and mines are reported, the distributions of doses presented and risk factors calculated. The bases of radon limitation for workers and members of the public are given and the means of compliance discussed. (author)

  9. Evaluation of radon and their daughters concentration and estimative of effective dose in a waste deposits at the ore treatment unity of INB/Pocos de Caldas, Brazil; Avaliacao da concentracao de radonio e seus filhos e estimativa de dose efetiva em um deposito de rejeitos na unidade de tratamento de minerios da INB/Caldas

    Energy Technology Data Exchange (ETDEWEB)

    Dantas, Marcelino V.A.; Garcia Filho, Oswaldo; Antunes, Marcos M.; Junior, Joao V.S.; Py Junior, Delcy A., E-mail: marcelino@inb.gov.b, E-mail: wspereira@inb.gov.b, E-mail: ogarcia@inb.gov.b, E-mail: antunes@inb.gov.b, E-mail: Joao@inb.gov.b, E-mail: delcy@inb.gov.b [Industrias Nucleares do Brasil (UTM/INB), Caldas, MG (Brazil). Unidade de Tratamento de Minerios; Pereira, Wagner S. [Industrias Nucleares do Brasil (UTM/INB), Caldas, MG (Brazil). Unidade de Tratamento de Minerios; Universidade Federal Fluminense (IB/UFF), Niteroi, RJ (Brazil). Inst. de Biologia. Lab. de Radiobiologia e Radiometria Pedro Lopes dos Santos

    2011-10-26

    This paper conducts a surveillance of radon and their short half-life daughters gas concentration, inside the warehouse due to these gas inhalation. The results showed that the average concentration inside the warehouse ix approximately 700 Bq/m{sup 3} and the effective dose of an IOE, related to that concentration would be 5.0 mSv/year, therefore being 4 times lower than the established limit of 20 mSv/year

  10. Influence of random daughter exposure rate, unattachment fraction, and disequilibrium on occurrence of lung tumors

    International Nuclear Information System (INIS)

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

    1983-10-01

    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. Modeled, 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. Experimental verification of these dose-effect relationships is needed to protect the health of workers and of the public exposed to radon-daughter environments. Data bearing on these relationships as well as updated results of experiments designed to test the role of radon-daughter exposure rate on lung-tumor incidence are reported. 13 references, 3 tables

  11. Evaluation of a Po-210 bioassay as an index of the exposure of uranium mine workers in Japan to radon daughters

    Energy Technology Data Exchange (ETDEWEB)

    Okabayashi, H; Suzuki, M; Hongo, S [National Inst. of Radiological Sciences, Chiba (Japan); Watanabe, S

    1975-06-01

    As an indicator nuclide for inhalation exposure of mine workders to Rn daughters in a Japanses uranium mine, /sup 210/Po urinalyses of the workers and surveys of some environmental factors were conducted. An estimation study of concentrations of Rn daughters in a mine, indicated that about 800-50 pCi of /sup 210/Po could have been accumulated in each miner's body. However, according to the results of urinalyses performed several times in 5 years, a statistical difference in the quantity of /sup 210/Po in urine among miners and non-mining workers there was not clearly identified. Investigations of /sup 210/Po concentrations in the mine's air, water, foods (of about 30 kinds) and cigarets, and investigations of feces-urine /sup 210/Po ratios in humans revealed that these factors would greatly affect the metabolism and /sup 210/Po excretion of the workers. In particular, some marine foods in Japan contained a great amount of /sup 210/Po (several hundreds times that of other foods) and cigarets showed 0.3-0.8 pCi of /sup 210/Po per gramme. Smokers definitely excreted more /sup 210/Po in urine than non-smokers. Feces-urine ratios ranged between 5.2-42.9 in one human subject. Therefore, it can be concluded that /sup 210/Po would not be a good indicator for human exposure to Rn daughters, unless great care is taken regarding the eating and smoking habits of mine workers, as well as the exposure conditions in the uranium mine.

  12. Radon concentration in The Netherlands

    International Nuclear Information System (INIS)

    Meijer, R.J. de; Put, L.W.; Veldhuizen, A.

    1986-02-01

    In 1000 dwellings, which can be assumed to be an reasonable representation of the average Dutch dwellings, time averaged radon concentrations, radon daughter concentrations and gamma-exposure tempi are determined during a year with passive dosemeters. They are also determined outdoor at circa 200 measure points. (Auth.)

  13. Instrumentation for a radon research house

    International Nuclear Information System (INIS)

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

    1981-07-01

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

  14. Uranium mill tailings and radon

    International Nuclear Information System (INIS)

    Hanchey, L.A.

    1981-01-01

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

  15. Uranium mill tailings and radon

    Energy Technology Data Exchange (ETDEWEB)

    Hanchey, L A

    1981-04-01

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

  16. Uranium mill tailings and radon

    Energy Technology Data Exchange (ETDEWEB)

    Hanchey, L A

    1981-01-01

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

  17. 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

  18. The reduction of radon hazard in smoke-free working environments

    International Nuclear Information System (INIS)

    Yu, K.N.; Young, E.C.M.; Guan, Z.J.; Liu, X.W.

    1996-01-01

    The variations in a number of properties related to radon as a result of the presence of cigarette smoke have been investigated in an unventilated room. These properties include the radon concentration, the total potential alpha energy concentration of radon daughters, the equilibrium factor and the fraction of unattached radon daughters. From the data collected, a sample calculation of the reduction of the radon dose in smoke-free working environments has been carried out. (Author)

  19. Application of CR-39 to radon measurement

    International Nuclear Information System (INIS)

    Miyake, Hiroshi

    1988-01-01

    CR-39, an ally diglycol carbonate, has recently come into wider use as material for solid-state track detector. Etching with NaOH or KOH solution allow CR-39 to develop extremely clear etch pits attributed to alpha rays. The most widely used method for measuring radon concentration employs a plastic cup with a solid-state track detector mounted at its bottom to detect alpha rays resulting from radon or its daughters that disintegrate within or on the wall of the cup. Simple in mechanism and low in cost, this method is suitable for such a case where the radon concentration distribution over a wide area has to be measured by using a large number of devices. The concentration of radon alone can be measured with the aid of a filter attached to the mouth of the cup to remove the daughters of radon and thoron. The simplest and most effective way of improving the sensitivity of a solid-state track detector for radon concentration measurement is to electrostatically collect daughters resulting from decay of radon onto the surface of the detector. Another method widely used to determine the radon concentration is to measure the concentration of the radon daughters instead of direct measurement of the concentration of radon itself. (Nogami, K.)

  20. Application of nuclear track detectors for radon related measurments

    International Nuclear Information System (INIS)

    Abu-Jarad, F.A.

    1988-01-01

    The application of nuclear track detectors for radon related measurements is discussed. The ''Can Technique'', used for measuring radon emanation from building materials, walls and soil; the ''Working Level Monitor'', used for measuring short period working levels of radon daughters in houses; and ''Passive Radon Dosimeters'', used to measure radon levels in houses for long term (few months) periods are described. Application of nuclear track detectors for measuring the radon daughters plate-out on the surface of mixing fan blades and walls are discussed. The uranium content of some wall papers was found to be 6 ppm. The variation of radon progeny concentration in the same room was measured and supported by another study through Gas Chromatograph measurements. The independence of radon concentration on room level in high-rise buildings was established. The effect of sub-floor radon emanation on radon concentration in houses is dependent on whether there is sub-floor ventilation or not. (author)

  1. Radon: an environmental pollutant

    International Nuclear Information System (INIS)

    Mills, W.A.

    1979-01-01

    Radiological concerns with the disposal and use of mining and milling residues have heightened to the point that federal agencies are asking or being asked to formulate new regulactions for controlling radon daughters from a variety of sources - radioactivity previously considered to be part of our natural environment. Based on information derived from epidemiologic studies of underground miners, particularly uranium miners, the health impact on the general public is being projected. Depending on the assumptions made, these projections vary widely. Because of these variations in health risks, decisions on control measures have even wider implications on economic and social considerations. Thus the question: is radon an environmental pollutant. While not fully answering the question, recognizing the uncertainties in assessing and controlling radon daughters can put the question in better perspective

  2. Automatically processed alpha-track radon monitor

    International Nuclear Information System (INIS)

    Langner, G.H. Jr.

    1993-01-01

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

  3. Modeling of indoor radon

    International Nuclear Information System (INIS)

    Paschoa, A.S.

    1990-01-01

    This paper reports on models for radon, which are developed not only to describe the behavior of radon and daughters since the moment that radon is created in natural sources by the alpha decay of 226 Ra up to the point that doses to humans are estimated based on the inhalation of radon and its progeny. The objective of a model should be determinant in defining the model structure and boundaries. Modeling indoors radon is particularly useful when the 226 Ra concentration in building materials and soils can be known before a house will be built with such 226 Ra bearing materials and over 226 Ra rich soils. The reported concentrations of 226 Ra in building materials range from 0.3 Bq · kg -1 in wood to about 2.6 x 10 3 Bq · kg -1 in aerated concrete based on alum shale. 30 In addition, when a house is built on a soil containing a high 226 Ra concentration, radon exhalation from the soil contributes to increase radon concentration indoors. The reported radon exhalation from soils range from 3.4 Bq · m -2 · s -1 in latosolic soil from Osaka, Japan to about 53 mBq · m -2 · s -1 in chernozemic soil from Illinois

  4. Monitoring of radon concentration in dwellings

    International Nuclear Information System (INIS)

    Kurosawa, Ryuhei

    1991-01-01

    Radon problems in dwellings have recently received much attention. Radon concentration in dwellings, as well as in the general environment, varies with various factors such as meteorological conditions and soil components. Therefore, a long term monitoring of radon concentration is required to obtain an average concentration. This paper reviews a passive type radon monitor that is handy and allows a long term radon monitoring. It provides the structure and principle of the radon monitor, covering the type, filter function, sensitivity of diffusion collecting type (cup type), electrostatic collecting type, adsorption collecting type, and detector of radon monitor. Actual examples of the radon monitor are also given. Radon daughter nuclides will have become major foci of exposure countermeasures. In the future, the development of a passive type monitor for determining potential alpha energy concentration is required. (N.K.)

  5. Behaviors of radon in indoor environment

    International Nuclear Information System (INIS)

    Mochizuki, Sadamu; Shimo, Michikuni.

    1987-01-01

    The source of radon ( 222 Rn) in the atmosphere is radioactive nuclide, uranium ( 238 U), which exists fairly common throughout the earth's crust. Radium ( 226 Ra) descended from uranium produce radon ( 222 Rn) of noble gas by decay. After formation in the ground, radon diffuses into the atmosphere. Without exception radon decay products are heavy metals which soon become attached to natural aerosols. Therefore, radon and its daughters (decay products) appear also in indoor environment, and generally, their concentration levels become higher than that of outdoor air due to build-up effects in the closed indoor environments. With the progress of the study on the influence of radon and its daughers on human health, it has become clear that they act effectively as an exciting cause of lung cancer. So, the study on the risk evaluation of them in room air has become to be very important. Concequently, the behaviors of radon and its daughters in indoor environment, first of all, should be studied in detail for the accurate estimation of the risk caused by them. In this special edition, fundamental characteristics of radon and its daughters, some measuring methods, theoretical considerations and some observational evidences obtained from various circumstances of indoor environment are described inorder to grasp and understand the behaviors of radon and its daughters in the indoor environment. (author)

  6. Radon measurements in some areas in Bangladesh

    International Nuclear Information System (INIS)

    Hamid Khan, M.A.; Chowdhury, M.S.

    2008-01-01

    A survey of radon level measurements using CR-39 has been carried out in some of urban and rural residential areas and one gas explosion area in Bangladesh. The lowest level of radon concentration was found to be 49Bqm -3 inside a hospital in Cox's Bazar district and the highest level was found to be 835Bqm -3 inside a mud-made old residential house in Sylhet city. It was observed that old residential houses were found to have higher levels of radon concentrations compared to newly built houses. The radon level at the gas explosion area at Magurchara in Moulvibazar district was found to be 408±98Bqm -3

  7. Radon activities in natural gases

    International Nuclear Information System (INIS)

    Sajo, B.L.; Palfalvi, J.

    1995-01-01

    Radon activities have been measured in gas samples used for residential heading, in Venezuela and in Hungary. Gas bottles were selected randomly in different regions, and radon activities were monitored with ionization clambers and solid stoke track detections. Radon concentrations in household natural gas are presented for regions in Venezuela and in Budapest, Hungary. The latter was found to be in the range of 88-135 Bq/m 3 . (R.P.)

  8. Thoron and radon measurements in houses

    International Nuclear Information System (INIS)

    Gauthier, C.

    1980-01-01

    Studies were made to determine what effect thoron daughters have on radon working level measurements in occupied houses at Elliot Lake. The decay of radon daughters is faster than that of thoron daughters. Six hours after sampling radon daughters are no longer present on the filter, and essentially all alpha activity is due to thoron C in transient equilibrium with thoron B. The concentrations can be extrapolated back to the time of the Kuznetz count, and the WL overestimation due to the presence of thoron daughters calculated. It was found using this method that in 70 percent of the samples the thoron contribution was no more than one mWL equivalent, less than the statistical error in the estimation of working levels. Only in buildings with very low ventilation rates and large areas of exposed concrete may corrections for the presence of thoron be necessary

  9. Certain problems about radon. Pt.1

    International Nuclear Information System (INIS)

    Wu Huishan

    2005-01-01

    Discussion has been made on certain pointed out problems which presently influence the work and development of radon survey, and certain specific problems have been put forward which should be paid much attention and taken measures. Among the problems, some come from cognition, i.e. two kinds of balance and examination about radon, chief culprit of radon's daughter, multiply control and migration, the significance of radon in the water and soil, important standards for designing and evaluating the sites of construction projects, thoughts on the mechanism of the harm of radon and its daughters, diseases causing of both high and low radon, difficulty of emanation of indoor radon, normal low radon from natural marble; and others must be resolved specifically, i.e. establishment of national radon standards as quickly as possible, improvement of on-the-spot examination technique, national-wide radon survey with multiple disciplines and technology, the research on the mechanism of radon's harm and the establishment national radon study center. (authors)

  10. Measurements of radon concentrations in dwelling houses

    International Nuclear Information System (INIS)

    Birkholz, W.; Klink, T.

    1993-01-01

    Radon and its daughter products gain in importance in health protection and radiation safety. Especially in the southern region of Saxony radon concentrations in dwellings may be high by former silver and uranium mines. We found radon contents of about 20.000 Bq/m 3 in dwellings. To redevelop such houses it is necessary to know intrude path of radon. In present work we studied different measuring systems, active and passive detectors, short and long term integrating devices. By means of investigation of radon sources several redeveloping methods are rates as well from radiological as from civil engineering point of view. (author)

  11. Radon concentration in a house of Calvados

    International Nuclear Information System (INIS)

    Leleyter, L.; Riffault, B.; Mazenc, B.

    2010-01-01

    Recent studies indicate a link between the risk of lung cancer and residential radon exposure. However, in France, awareness of this problem was made relatively late. Accordingly this study examines the radon concentration in a private home in Calvados (Normandy region). Findings show that the presence of a fireplace in a house can accelerate radon convective transfer, and that simple adjustments to interior and exterior accommodation can significantly reduce radon concentrations in the home. (authors)

  12. Locating and limiting radon in dwellings

    International Nuclear Information System (INIS)

    Hildingson, O.; Gustafsson, J.; Nilsson, I.

    1984-01-01

    More than 3,300 Swedish dwellings have an indoor radon daughter concentration above 400 Bq.m -3 (or 0.108 WL). It is considered to be unsafe to live in any of these dwellings and the radon daughter concentration has to be reduced. Before deciding what measures to take, it is important to determine the radon sources. Possible sources are exhalation from building materials and/or radon transport from the ground into the building through cracks and joints in the slab. Different methods of locating the sources have been developed. To locate cracks and joints in slabs the ventilation rate and the air pressure difference relative to the ground are changed while monitoring radon/radon daughter concentration. The effect of five different measures to reduce the indoor radon daughter concentration have also been evaluated: increased ventilation rate by mechanical ventilation, ventilation of the small spaces between the floor and the slab, sealing the surface of radon exhaling walls, sealing joints and cracks in the slab, and ventilation of the drainage under the slab. (author)

  13. Radon assay for SNO+

    Energy Technology Data Exchange (ETDEWEB)

    Rumleskie, Janet [Laurentian University, Greater Sudbury, Ontario (Canada)

    2015-12-31

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

  14. Radon in the life environment and its countermeasures of prevention and control

    International Nuclear Information System (INIS)

    Li Zhenyuan; Zhang Shucheng

    2004-01-01

    Radon and its daughters are a primary component for human body received total natural radiation. They will hurt human body, even fall ill when human body is over-received radiation permitted in the life environment, especially indoors. The paper introduces mainly production mechanism of the radon and its daughters at indoor environment, the live environment investigation and monitoring technology, and effect factors on the radon concentration and distribution, as well as protection and control countermeasures for radon. (authors)

  15. Dust and radon: the legal implications

    International Nuclear Information System (INIS)

    Van Sittert, J.M.O.

    1990-01-01

    It is known that radon gas is not generally considered to be a major problem when encountered in the working environment. However, in its process of decay, a series of four short lived daughter products are formed. In a dust-laden atmosphere these daughter products, which are ionized readily, attach to the particulate material and when inhaled are deposited in the alveoli of the lungs. Therefore, if respirable dust is controlled, the effects of radon daughters will also be minimized. The legal requirements for dust control in South Africa and their implications are discussed. 1 ill

  16. A continuous monitor for the measurement of environmental radon

    International Nuclear Information System (INIS)

    Chittaporn, P.; Eisenbud, M.; Harley, N.H.

    1981-01-01

    Although inhaled short-lived 222 Rn daughters deliver the pertinent α dose for assessing human health effects, radon daughters do not of themselves exist in any atmosphere for more than 2-3 hr. Their long-lived parent (3.82 day) 222 Rn supports the daughter activity and it is the transport of 222 Rn which ultimately determines dose. Without an understanding of the long and short-term temporal patterns of indoor and outdoor 222 Rn it is impossible to understand the factors which are important in establishing any human health hazard from the daughters. This work describes a new continuous environmental radon monitor which measures radon alone without interference from radon daughters. The detector is a cylinder (13 cm diameter x 14 cm high), is lined with alpha scintillation phospor on a Mylar substrate and is portable and easily constructed from inexpensive and commercially available materials. (author)

  17. Individual dosimeter for radon and thoron daughters

    International Nuclear Information System (INIS)

    Chapuis, A.M.; Duport, P.; Zettwoog, P.

    1979-01-01

    The dosimeter is designed for the continuous measurement of the concentration of α emitters from the uranium 238 and thorium 232 series. It enables the measurement of, firstly the aerosol concentration of 218 Po (Radium A), 214 Po (Radium C') and 212 Po (Thorium C') and secondly the activity of long-lived α emitters in aerosols coming from ore dusts. One light weight version of this dosimeter is autonomous for 18 hours and is designed to measure individual doses, due to inhalation, for workers employed in uranium mines and ore processing plants. An other version using the same sampling head allows the monitoring of air concentrations in working environments. Living quarters, or free air

  18. Radon in Croatian spas

    International Nuclear Information System (INIS)

    Radolic, V.; Vukovic, B.; Planinic, J.

    2004-01-01

    There are ten thermal spas in Croatia and all of them provide health services for patients and visitors. Radon measurements were performed since there is a lack of data concerning natural radioactivity originated from radon and its short-lived progenies in such environments. The thermal water at two different sites (the indoor swimming pool with geothermal water and the spring) in each spa was sampled and radon concentrations were measured by AlphaGUARD radon measuring system. The obtained values were in the range of 0.7 to 19 Bq.dm -3 and 2 to 94 Bq.dm -3 for indoor swimming pools and springs, respectively. Integrated measurements of radon concentration in air were performed by two solid state nuclear track detectors LR-115 II (open and diffusion one) thus enabling estimation of equilibrium factor between radon and its daughters. The annual effective doses received by spa workers were found to be about 1 mSv/y (below the lower limit value of 3 mSv/y recommended by ICRP 65). The doses of patients and visitors were one or two order of magnitude lower than that of the personnel. (author)

  19. An overview of PNL radon experiments with reference to epidemiological data

    International Nuclear Information System (INIS)

    Cross, F.T.; Palmer, R.F.; Busch, R.H.; Dagle, G.E.; Filipy, R.E.; Ragan, H.A.

    1986-01-01

    Biological effects observed in dogs and rodents after the inhalation of radon and radon daughters have included, primarily, respiratory carcinoma, pulmonary fibrosis, emphysema, and life-span shortening. Extrapulmonary lesions observed are not considered significant except for certain hematological effects. In this paper we present biological effects data resulting from chronic exposures of hamsters, rats, and beagle dogs. Emphasis is placed on the carcinogenic effects of radon and radon daughters, including the influences of radon-daughter exposure rate, unattachment fraction, and disequilibrium and of concomitant exposure to other pollutants. These data are correlated with results from human epidemiological studies. Plausible values for the radon (radon-daughter) lifetime lung-cancer risk coefficient are provided. 30 refs., 3 tabs

  20. Radon epidemiology: A guide to the literature

    International Nuclear Information System (INIS)

    Marks, S.

    1988-12-01

    This document was written as a comprehensive overview of the voluminous literature on both uranium miner and residential radon epidemiology studies. This document provides the reader with a fairly complete list of radon epidemiology publications and key features of each, so that readers may further pursue only those publications of interest in the vast body of radon literature. A companion document, exploring all on-going residential radon epidemiology studies will be published by the Office of Health and Environmental Research (OHER), the Department of Energy (DOE) in the spring of 1989

  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. Radon: a bibliography

    International Nuclear Information System (INIS)

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

    1981-01-01

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

  3. Radon: a bibliography

    Energy Technology Data Exchange (ETDEWEB)

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

    1981-01-01

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

  4. Environmental radon

    International Nuclear Information System (INIS)

    Majumdar, S.K.; Schmalz, R.F.; Miller, E.W.

    1990-01-01

    This book covers many aspects of environmental radon, including: historical perspectives; occurrence and properties; detection, measurement, and mitigation, radon and health; and political, economic, and legislative impacts

  5. Indoor radon concentration in Poland

    International Nuclear Information System (INIS)

    Mamont-Ciesla, K.; Jagielak, J.; Rosinski, S.W.; Sosinka, A.; Bysiek, M.; Henschke, J.

    1996-01-01

    Preliminary survey of Rn concentration indoors by means of track detectors and y-ray dose rate with the use of TLD in almost 500 homes in selected areas of Poland was performed in the late 1980s. It was concluded that radon contributes 1.16 mSv i.e. about 46 per cent of the total natural environment ionizing radiation dose to the Polish population. Comparison of the average radon concentrations in 4 seasons of a year and in 3 groups of buildings: masonry, concrete and wood, revealed that the ground beneath the building structure is likely the dominant source of radon indoors. Since the National Atomic Energy Agency in its regulations of 1988-03-31 set up the permissible limit of the equilibrium equivalent concentration of radon in new buildings (equal 100 Bq/m3), the nation-scale survey project for radon in buildings has been undertaken. These regulations were supposed to take effect in 1995-01-01. The project has 3 objectives: to estimate the radiation exposure due to radon daughters received by Polish population to identify radon-prone areas in Poland to investigate dependence of the indoor radon concentrations on such parameters as: type of construction material, presence (or absence) of cellar under the building, number of floor

  6. Lung cancer mortality and indoor radon concentrations in 18 Canadian cities

    International Nuclear Information System (INIS)

    Letourneau, E.G.; Mao, Y.; McGregor, R.G.; Semenciw, R.; Smith, M.H.; Wigle, D.T.

    1983-01-01

    Indoor radon and radon daughter concentrations were measured in a survey of 14,000 homes in 18 Canadian cities conducted in the summers of 1978 through 1980. Mortality and population data for the period 1966 through 1979 were retrieved for the geographic areas surveyed in each city. The results of analysis of the relation between lung cancer and radon daughter concentration, smoking habits and socioeconomic indicators for each city showed no detectable association between radon daughter concentrations and lung cancer mortality rates with or without adjustment for differences in smoking habits between cities

  7. Radon in water aeration system operational performance

    International Nuclear Information System (INIS)

    Lamarre, B.L.

    1990-01-01

    North East Environmental Products, Inc. is a manufacturer of residential scale aeration systems for removal of radon and volatile organic chemicals from private water supplies. This paper is a review of the operational history of residential scale point of entry (POE) radon aeration systems. Emphasis is placed on the difficulties and solutions encountered in actual installations caused by both mechanical difficulties and water quality parameters. A summary of radon reduction efficiency is presented for wells with radon concentrations from 21,000 to 2,600,000 pCi/L. A discussion of customer concerns and attitudes is presented along with other areas for further technical improvement. Training techniques for dealers and installers are also discussed. An update of the current status of the radon in water industry includes current sales volumes as compared to the potential market and an update on the radon in water MCL standard setting process from an industry perspective

  8. Ventilation measurements as an adjunct to radon measurements in buildings

    International Nuclear Information System (INIS)

    Knutson, E.O.; Franklin, H.

    1977-01-01

    The concentration of radon in a building is a function of the radon sources within the building and of the building's ventilation characteristics. To complement its radon measurement program, HASL is currently assessing apparatus and procedures for measuring building ventilation. Results are reported from ventilation measurements made in the laboratory and in a residential building

  9. Radon hazard from caisson and tunnel construction in Kong Kong

    International Nuclear Information System (INIS)

    Lam, W.K.; Tsin, T.W.; Ng, T.P.

    1988-01-01

    A possible occupational risk of caisson and tunnel excavation in Hong Kong results from the inhalation of natural radon daughters. In this study radon daughter concentrations ranging from 0.001 to 71.4 WL were recorded in caissons of various dimensions and from 0.03 to 0.95 WL in tunnels over 1 km in length under construction (ICRP exposure limit being 0.4 WL). There was clear indication of increased radon daughter accumulation in confined and unventilated areas and in unventilated caissons an exponential increase of radon daughter concentration with the ratio of depth to cross-sectional area was observed (r=0.9). The study revealed a potential radiation hazard facing underground construction workers and this is being examined by an ongoing epidemiological cohort study: meanwhile environmental control should be improved. (UK)

  10. Radon analyser

    International Nuclear Information System (INIS)

    1981-01-01

    The process claimed includes the steps of transferring radon gas produced by a sample to a charcoal trap, cooled to a temperature whereby the radon is absorbed by the charcoal, heating the charcoal trap to a sufficient temperature to release the radon, and transferring the radon to a counting device where the gas particles are counted

  11. Indoor radon measurements in dwellings of Garhwal Himalaya, Northern India

    International Nuclear Information System (INIS)

    Ramola, R.C.

    1996-01-01

    Measurement of indoor radon and daughters concentration were performed in several houses in Garhwal Himalaya during 1993-95 with solid state nuclear track detector films (LR-115 Type II). The detector films were exposed for a period of three month to one year. The films basically measured total airborne alpha activity but may be calibrated in unite of EEC RN (equilibrium equivalent concentration of radon with equilibrium factor F=0.45) in an environment with known radon and daughters concentrations. A numbers of dwelling in the area exhibited radon daughters concentrations (EEC RN ) exceeding the recommended level. The abnormal values are due to typical house construction (mud house) in the area. The houses are constructed with soil and local stone with a thin paste of mud. Behaviour and abnormality of radon in mud houses are discussed in details the corresponding annual effective dose has been calculated. (author)

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

    International Nuclear Information System (INIS)

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

    1996-01-01

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

  13. Contribution of waterborne radon to home air quality

    International Nuclear Information System (INIS)

    Deb, A.K.

    1994-01-01

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

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

    International Nuclear Information System (INIS)

    Harley, N.H.

    1990-01-01

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

  15. Assessing the risks from exposure to radon in dwellings

    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

  16. Radon campaigns. Status report 2008

    International Nuclear Information System (INIS)

    Arvela, H.; Valmari, T.; Reisbacka, H.; Niemelae, H.; Oinas, T.; Maekelaeinen, I.; Laitinen-Sorvari, R.

    2008-12-01

    Radon campaigns aim at activating citizens to make indoor radon measurements and remediation as well as increasing the common awareness of indoor radon questions. Indoor radon increases the risk of lung cancer. Through radon campaigns Radiation and Nuclear Safety Authority (STUK) also promotes the attainment of those goals that the Ministry of Social Affairs and Health has set for municipal authorities in Finland for prevention of the harmful effects of radon. The Ministry of Social Affairs and Health supports this campaign. Radon campaigns were started in autumn 2003. By autumn 2008 the campaigns have been organised already in 64 regions altogether in 160 municipalities. In some municipalities they have already arranged two campaigns. Altogether 14 100 houses have been measured and in 2 100 of these the action limit of radon remediation 400 Bq / m 3 has been exceeded. When participating in radon campaigns the house owners receive a special offer on radon detectors with a reduced price. In 2008 a new practice was introduced where the campaign advertisements were distributed by mail to low-rise residential houses in a certain region. The advertisement includes an order / deposit slip with postage paid that the house owner can send directly to STUK to easily make an order for radon measurement. In the previous radon campaigns in 2003 - 2007 the municipal authorities collected the orders from house owners and distributed later the radon detectors. The radon concentrations measured in the campaign regions have exceeded the action limit of 400 Bq / m 3 in 0 - 39% of houses, depending on the region. The total of 15% of all measurements made exceeded this limit. The remediation activities have been followed by sending a special questionnaire on remedies performed to the house owners. In 2006 - 2007 a questionnaire was sent to those households where the radon concentration of 400 Bq / m 3 was exceeded during the two first campaign seasons. Among the households that replied

  17. Radon in Schools

    Science.gov (United States)

    ... Search Search Radon Contact Us Share Radon in Schools Related Information Managing Radon in Schools Radon Measurement ... Radon Could Be a Serious Threat to Your School Chances are you've already heard of radon - ...

  18. Concentration en radon dans une maison du Calvados

    Science.gov (United States)

    Leleyter, Lydia; Riffault, Benoit; Mazenc, Bernard

    2010-03-01

    Recent studies indicate a link between the risk of lung cancer and residential radon exposure. However, in France, awareness of this problem was made relatively late. Accordingly this study examines the radon concentration in a private home in Calvados. Findings show that the presence of a fireplace in a house can accelerate radon convective transfer, and that simple adjustments to interior and exterior accommodation can significantly reduce radon concentrations in the home.

  19. Etched track radiometers in radon measurements: a review

    CERN Document Server

    Nikolaev, V A

    1999-01-01

    Passive radon radiometers, based on alpha particle etched track detectors, are very attractive for the assessment of radon exposure. The present review considers various devices used for measurement of the volume activity of radon isotopes and their daughters and determination of equilibrium coefficients. Such devices can be classified into 8 groups: (i) open or 'bare' detectors, (ii) open chambers, (iii) sup 2 sup 2 sup 2 Rn chambers with an inlet filter, (iv) advanced sup 2 sup 2 sup 2 Rn radiometers, (v) multipurpose radiometers, (vi) radiometers based on a combination of etched track detectors and an electrostatic field, (vii) radiometers based on etched track detectors and activated charcoal and (viii) devices for the measurement of radon isotopes and/or radon daughters by means of track parameter measurements. Some of them such as the open detector and the chamber with an inlet filter have a variety of modifications and are applied widely both in geophysical research and radon dosimetric surveys. At the...

  20. Radon and energy efficient homes

    International Nuclear Information System (INIS)

    Burkart, W.

    1981-09-01

    Radon and its daughters in indoor air are presently responsible for dose equivalents of about 31 mSv/year (3 rem/year) to parts of the respiratory tract. Linear extrapolation from the dose response values of uranium miners heavily exposed to radon and its decay products would suggest that almost all lung cancers in the non-smoking population are caused by environmental 222 Rn. Using epidemiological data on the types of lung cancer found in non-smokers of the general public as compared to the miners, a smaller effect of low level radon exposure is assumed, which would result in a lung cancer mortality rate due to radon of about 10 deaths per year and million or 25% of the non-smoker rate. Higher indoor radon concentrations in energy efficient homes mostly caused by reduced air exchange rates will lead to a several fold increase of the lung cancer incidence from radon. Based on the above assumption, about 100 additional lung cancer deaths/year-million will result both from an increase in radionuclide concentrations in indoor air and a concomitant rise in effectiveness of radiation to cause cancer with higher exposure levels. Possibilities to reduce indoor radon levels in existing buildings and costs involved are discussed. (Auth.)

  1. Soil Radon In The Nigerian Younger Granites | Dewu | Nigerian ...

    African Journals Online (AJOL)

    ... not had enough time to attain equilibrium with its daughters. In general, the results suggest that with proper control, soil radon measurements over the Younger Granite can be used for uranium exploration in the region. Keywords: Radon, younger granite, soil uranium, half-lifeand thorium. Nigerian Journal of Physics Vol.

  2. A study of radon variation in dwelling during 1988

    International Nuclear Information System (INIS)

    Shaikh, A.N.; Ramachandran, T.V.; Muraleedharan, T.S.; Subbaramu, M.C.

    1989-01-01

    Natural radioactivity due to radon and its progeny levels indoors contributes significantly to the total radiation to man. The main source of radon and its progeny in a dwelling is the emanation of radon gas from soil. The temperature and ventilation vary in a dwelling during the year. These parameters influence the indoor radon levels. The seasonal variation of radon was studied in a dwelling as well as in the outside air. The filter paper method and alpha counting, and the solid state track detector technique and track counting were used to study the radon levels. The geometric mean of radon daughters concentrations were 0.5 mWL and 0.8 mWL measured by filter-paper method and SSNTD method respectively. The geometric mean of radon concentrations were 6.2 Bqm -3 and 10.0 Bqm -3 by filter-paper method and SSNTD method respectively. (author). 3 figs., 3 tabs., 13 refs

  3. Radon measurements indoors

    International Nuclear Information System (INIS)

    Joensson, G.

    1983-02-01

    Measurements of Radon concentrations have been made using photographic film detectors in the communities of Uppsala, Soedertaelje and Tyresoe. The result from 6700 filmexposures in both one-family and apartment houses are reported. The fraction of dwellings with radon daughter concentrations exceeding 200 Bq/m 3 is between 3 and 14 percent for one-family houses and 0 to 5 percent for apartment buildings. 8 to 68 percent of the one-family houses and 57 to 83 percent of the apartment buildings had concentrations lower than 70 Bq/m 3 . The seasonal variations were recorded in one-family houses in Uppsala. In houses with low concentrations, the winter values were higher than the summer values. For houses with high concentrations the reversed variation was recorded. (Author)

  4. Definition of correcting factors for absolute radon content measurement formula

    International Nuclear Information System (INIS)

    Ji Changsong; Xiao Ziyun; Yang Jianfeng

    1992-01-01

    The absolute method of radio content measurement is based on thomas radon measurement formula. It was found in experiment that the systematic error existed in radon content measurement by means of thomas formula. By the analysis on the behaviour of radon daughter five factors including filter efficiency, detector construction factor, self-absorbance, energy spectrum factor, and gravity factor were introduced into the thomas formula, so that the systematic error was eliminated. The measuring methods of the five factors are given

  5. A survey of indoor radon concentrations inSweden

    International Nuclear Information System (INIS)

    Buren, A.; Mjoenes, L.; Wennberg, P.

    1982-01-01

    The average value for family houses is calculated to be 121 Bq/m 3 , and 87 Bq/m 3 for flats in apartment houses. Demographic statistics render an average value per person of 105 Bq/m 3 . Radon has been measured in small houses built 1978 to 1980 and their average value was found to be 59 Bq/m 3 . The values are presented for radon which permits calculating radon daughters. (GB)

  6. Alpha-particle dosimetry using solid state nuclear track detectors. Application to 222Rn and its daughters

    International Nuclear Information System (INIS)

    Barillon, R.; Chambaudet, A.

    2000-01-01

    A methodology for the determination of the detection efficiency of a solid state nuclear track detector for radon and its short-lived daughters was presented. First, particular attention is paid to the α-particles having energies and angles of incidence that lead to observable tracks after an adapted chemical etching. The results are then incorporated in a mathematical model to determine the theoretical radon detection efficiency of a polymeric detector placed in a cylindrical cell. When applied to LR115 and CR39 detectors, the model reveals the influence of the position of the radon daughters inside the cell. Radon daughters tend to link up with natural atmospheric aerosols and then settle on the cell's inside wall. This model allows to determine, among other things, the cell size for which the detector response is independent of the fraction daughters plated out. (author)

  7. Radon and hydrotherapy: application to French spas

    International Nuclear Information System (INIS)

    Ameon, R.

    2004-01-01

    Owing to the use of thermal water for treatments, the dissolved radon ends up, through degassing, in the atmosphere of the various spa premises. According to the type of treatments, the radon activity concentration in the air is very variable; it depends on two factors, the supply of thermal water, and therefore of radon, and the ventilation of the various premises. In unfavourable, even non-existent, ventilation conditions, it is not uncommon to measure radon concentration reaching several thousands of becquerels per air cubic meter. These high values of radon activity concentration, with or without its short-lived daughters, may lead to a staff exposure of approximately ten or several tens of mSv per year. A French spa was subject to a radon 'expertise' during which the radon source terms, 'ground in contact with the buildings' and 'thermal water' were characterized. The radon mapping in the internal atmosphere of the various spa premises and the workstations' analysis resulted in an assessment of the exposure due to radon inhalation. This study showed that on workstations, notably linked to hydrotherapy, the staff exposure to radon is in the same range as the dose assessments from foreign studies. The implementation of an appropriate ventilation of the treatment rooms and a better management of the thermal water in the spa resulted in a significant reduction of staff exposure

  8. A radon meter chamber

    International Nuclear Information System (INIS)

    Carlsson, R.

    1990-01-01

    The meter consists of a cylindrical house with two openings, at the ends, one of which is equipped with an alpha particle detector and the other covered with a metal net. The house is manufactured in an isolating material e.g. plastic, with a metallic layer applied to all internal surfaces. The metallic layer and net are kept at a positive electric potential, compared to the alpha detector, in order to attract the radon daughters to the detector and achieve a high efficiency. (L.E.)

  9. Development of a small-sized radon data logger

    International Nuclear Information System (INIS)

    Tasaka, Shigeki; Sasaki, Yoshimi

    1996-01-01

    A small-sized radon data logger and a electrostatic collecting radon monitor were developed for the continuous monitoring of environmental radon and radon daughters. A PIN photodiode (PD), an alpha particle defector, installed inside a container attracts radon daughters when charged electrostatically. Alpha particles are completely separated from each other according to the energy level. New logger has made it possible 10 analysts and save the radon data. Alpha particle count data from radon daughters are automatically integrated over preset time intervals and the energy regions. The desiccant P 2 O 5 was placed in the bottom of the monitor, since the collection efficiency of 218 Po atoms depends on the humidity of the air. We can get the 30 days continuous data logging at 30 min sampling frequency at any place with the car battery. We observed the radon concentration of the air inside the Super-Kamiokande dome from Jan-30 to Feb-8-1996. The average of radon concentration was found to be (46±13) Bq/m 3 . (author)

  10. Radon measurements in some areas in Bangladesh

    Energy Technology Data Exchange (ETDEWEB)

    Hamid Khan, M.A. [Physics Division, Atomic Energy Centre, Bangladesh Atomic Energy Commission, P.O. Box 164, Dhaka-1000 (Bangladesh)], E-mail: hamidkhan1950@yahoo.com; Chowdhury, M.S. [Physics Department, Dhaka University, Dhaka-1000 (Bangladesh)

    2008-08-15

    A survey of radon level measurements using CR-39 has been carried out in some of urban and rural residential areas and one gas explosion area in Bangladesh. The lowest level of radon concentration was found to be 49Bqm{sup -3} inside a hospital in Cox's Bazar district and the highest level was found to be 835Bqm{sup -3} inside a mud-made old residential house in Sylhet city. It was observed that old residential houses were found to have higher levels of radon concentrations compared to newly built houses. The radon level at the gas explosion area at Magurchara in Moulvibazar district was found to be 408{+-}98Bqm{sup -3}.

  11. Analysis of radon reduction by ventilation in uranium mines in China

    International Nuclear Information System (INIS)

    Hu Penghua; Li Xianjie

    2011-01-01

    Mine ventilation is the most important way to reduce radon in uranium mines. At present, the concentrations of radon and its daughters in underground air is 3-5 times higher than those in other countries, at the same protection conditions. In this paper, through the analysis of radon reduction status in Chinese uranium mines and the comparison of advantages and shortcomings between variety of ventilation and radon reduction measures, the reasons for higher radon and radon daughter concentration in Chinese uranium mines are discussed and some problems are put forward in three aspects: radon reduction ventilation theory, measures and management. Based on above problems, this paper puts forward some proposals and measures, such as strengthening examination and verification and monitoring practical situation, making clear ventilation plan, training ventilation technician, enhancing ventilation system management, developing radon reduction ventilation research and putting ventilation equipment in place as soon as possible in future. (authors)

  12. Environmental radon and thoron monitor

    International Nuclear Information System (INIS)

    Thomas, J.W.

    1977-01-01

    A large two-filter type monitor (ERM-3) has been developed for measuring environmental levels of radon and thoron to within several picocuries per cubic meter. The inlet filters of the monitor remove daughter activity from the entering air stream but permit radon and thoron to pass. Daughter activity formed in the 0.9 m 3 decay chamber is collected by the fixed exit filter. The alpha activity of the filter is detected with a zinc sulfide scintillator and a 12 cm phototube, counted with an automatic timer and scaler, and is printed out on a teletypewriter for predetermined counting intervals. The teletypewriter also punches a tape to provide computer-compatible readout

  13. 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

  14. Radon as a risk factor in mines and dwellings

    Energy Technology Data Exchange (ETDEWEB)

    Axelson, O [Yrkesmedicinska kliniken, Regionsjukhuset, Linkoeping (Sweden)

    1985-03-01

    In mines, exposure to radon and radon daughters is the most important factor for the initiation of lung cancer. Tobacco smoke probably acts as a lung cancer promotor, but the relationship between minework, smoking and lung cancer is complicated. It is suggested that smokers may have a relative protection from a mucous sheet covering their basal cells. There is a connection between radon exposure in dwellings and lung cancer. Radon in buildings comes from the building material or the ground. The risk for developing lung cancer seems to be enhanced considerably by smoking. Tobacco contains some radioactivity itself (Lead 210 and Polonium 210), but tobacco smoke also adsorb electrically charged radon daughters and keeps them floating in the breathing air. Measurements show a doubling of radon daughter concentration in a room of normal size if 3-4 cigarettes are burnt out in it. A raised risk for lung cancer has been observed in connection with passive smoking. The relative risk for lung cancer is 2-3 for passive smokers and 5-6 for active smoking women. Children of smoking mothers who start smoking themselves develop lung cancer more easily than other groups. There seems to be a connection between early exposure to radon daughters, passive smoking and lung cancer.

  15. Measurements of parameters for determining the radon load in the framework of the Dutch national research program SAWORA

    International Nuclear Information System (INIS)

    Groen, G.C.H.; Groot, T.J.H. de; Nyqvist, R.G.; Keverling Buisman, A.S.; Stoute, J.R.D.

    1986-06-01

    This report describes a series of measurements related to the indoor exposure to daughters of radon and thoron. Important parameters are the Potential Alpha Energy Concentration (PAEC) and the Activity Median Aerodynamic Diameter (AMAD). The results for indoor atmosphere are presented leading to an order of magnitude estimate of the effective dose-equivalent rate of 500 μSv/y. The thoron daughter concentrations are relatively high with respect to those of radon daughters. (Auth.)

  16. Analysis on present radon ventilation situation of Chinese uranium mines

    International Nuclear Information System (INIS)

    Li Xianjie; Hu Penghua

    2010-01-01

    Mine Ventilation is the most important way in lowering radon of uranium mines. At present, radon and radon daughter concentration of underground air is 3∼5 times higher than any other air concentration of foreign uranium mines, as the same input for Protective Ventilation between Chinese uranium mines with compaction methodology and international advanced uranium mines. In this passage, through the analysis of Ventilation Radon Reduction status in Chinese uranium mines and the comparison of advantages and shortcomings between variety of ventilation and radon reduction, it illuminated the reasons of higher radon and radon daughter concentration in Chinese uranium mines and put forward some problems in three aspects, which are Ventilation Radon Reduction Theory, Ventilation Radon Reduction Measures and Ventilation Management. And to above problems, this passage put forward some proposals and measures about some aspects, such as strengthen examination and verification and monitoring practical situation, making clear ventilation plan, in according to mining sequence strictly, training Ventilation technician forcefully, enhance Ventilation System management, development of Ventilation Radon Reduction technology research in uranium mines and carrying out ventilation equipments as soon as possible in further and so on. (authors)

  17. Methods and instruments available for the measurement and study of radium, radon and other alpha-particle-emitting radioisotopes of the 238U radioactive decay chain in soils, rocks and solutions

    International Nuclear Information System (INIS)

    McCorkell, R.

    1980-01-01

    The author describes methods used in his laboratory to determine radon, radon daughter, uranium and radium concentrations in air, soil gas, and aqueous solutions. These methods include emanometry, the use of track detectors or collectors, filtration, and autoradiography

  18. Relationship between indoor radon and lung cancer: a study of feasibility of an epidemiological study. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, S.; Neuberg, D.; DuMouchel, W.; Kleitman, D.; Chernoff, H.

    1981-01-01

    This report describes a study to assess the feasibility of an epidemiologic investigation of the relationship between residential radon exposure and lung cancer. Field measurements of residential radon levels in the State of Maine are described. Using these radon measurements and BEIR, 1980 risk assessments, it is estimated that at most 10% of lung cancers in Maine can be considered attributable to residential radon exposure. Calculations are made of sample sizes necessary for a case-control study of radon and lung cancer, for several levels of radon and smoking health effects. The effects of misclassification of exposure variables on the probability of detecting a radon health effect are discussed. A comparison is made of three different mathematical models which could be used for sample size estimation. Dollar cost estimates are given for conducting an epidemiologic case-control study of the relationship between residential radon exposure and lung cancer.

  19. Relationship between indoor radon and lung cancer: a study of feasibility of an epidemiological study. Final report

    International Nuclear Information System (INIS)

    Rasmussen, S.; Neuberg, D.; DuMouchel, W.; Kleitman, D.; Chernoff, H.

    1981-01-01

    This report describes a study to assess the feasibility of an epidemiologic investigation of the relationship between residential radon exposure and lung cancer. Field measurements of residential radon levels in the State of Maine are described. Using these radon measurements and BEIR, 1980 risk assessments, it is estimated that at most 10% of lung cancers in Maine can be considered attributable to residential radon exposure. Calculations are made of sample sizes necessary for a case-control study of radon and lung cancer, for several levels of radon and smoking health effects. The effects of misclassification of exposure variables on the probability of detecting a radon health effect are discussed. A comparison is made of three different mathematical models which could be used for sample size estimation. Dollar cost estimates are given for conducting an epidemiologic case-control study of the relationship between residential radon exposure and lung cancer

  20. Absolute measurement method of environment radon content

    International Nuclear Information System (INIS)

    Ji Changsong

    1989-11-01

    A portable environment radon content device with a 40 liter decay chamber based on the method of Thomas double filter radon content absolute measurement has been developed. The correctness of the method of Thomas double filter absolute measurement has been verified by the experiments to measure the sampling gas density of radon that the theoretical density has been known. In addition, the intrinsic uncertainty of this method is also determined in the experiments. The confidence of this device is about 95%, the sensitivity is better than 0.37 Bqm -3 and the intrinsic uncertainty is less than 10%. The results show that the selected measuring and structure parameters are reasonable and the experimental methods are acceptable. In this method, the influence on the measured values from the radioactive equilibrium of radon and its daughters, the ratio of combination daughters to the total daughters and the fraction of charged particles has been excluded in the theory and experimental methods. The formula of Thomas double filter absolute measuring radon is applicable to the cylinder decay chamber, and the applicability is also verified when the diameter of exit filter is much smaller than the diameter of inlet filter

  1. Survey of indoor radon concentrations in Fukuoka and Kagoshima prefectures

    International Nuclear Information System (INIS)

    Kunugita, Naoki; Norimura, Toshiyuki; Tsuchiya, Takehiko

    1990-01-01

    It is now well established that radon and its daughter products account for nearly half of the average population exposure to ionizing radiations and that radon is the greatest single source of natural radiation to the population. Radon and its daughters are alpha-emitters, which are more biologically damaging than beta- and gamma-radiations. A nationwide survey of radon concentration was conducted by the National Institute of Radiological Sciences in order to estimate the contribution of radon and its daughters to the population dose in Japan. Authors surveyed indoor radon concentrations in Fukuoka and Kagoshima prefectures as part of this project. A passive type radon dosimeter, in which a sheet of polycarbonate film as the alpha-ray detector was mounted, was used to measure indoor radon concentrations. The resulting distribution of the average annual indoor radon concentrations in both prefectures can be characterized by an arithmetic mean of 24.4 Bq/m 3 and a standard deviation of 13.1 Bq/m 3 , by a geometric mean of 22.2 Bq/m 3 , and by a median of 20.7 Bq/m 3 . The geometric means of the distributions for Fukuoka and Kagoshima were 25.4, and 18.4 Bq/m 3 , respectively. Radon concentrations were also generally high in winter and low in summer. Regarding the analysis of correlations between the concentrations and construction materials, radon concentrations were generally high in Japanese houses with earthen walls and in concrete structures. These results showed that seasons, the type of building materials, and regional differences were significant factors in the variation of indoor radon concentration. (author)

  2. 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

  3. Indoor radon epidemiological study

    Energy Technology Data Exchange (ETDEWEB)

    Kunz, E; Tomasek, L; Mueller, T [National Radiation Protection Institute, Prague (Czech Republic); Placek, V [Inst. for Expertises and Emergencies, Pribram-Kamenna (Czech Republic); Matzner, J; Heribanova, A [State Office for Nuclear Safety, Prague (Czech Republic)

    1996-12-31

    The study is a long-term prospective cohort study of lung cancer and possibility other causes of death. The study population includes inhabitants of the area, who had resided there for at three years and at least one of these between 1.1.1960 and 21.12.1989. A total of 11865 inhabitants satisfied these criteria. The cumulative exposure of each respondent is being assessed on the basis of measurements in dwellings, time spent there and estimation of previous exposure levels by a model accounting for constructional changes in buildings. One year lasting measurements of radon daughter products by integral dosimeters (Kodak film LR 115) were performed in practically all dwellings of the specified area. Radon measurements in houses in term of equilibrium concentration are compared with the results of a pilot study in Petrovice in 1990-91 which gave the stimulus for the epidemiological study. The distribution of death causes and ratio of observed (O) to expected (E) cases among collected death cases in the cohort, generally, somewhat lower ratios than one reflect the non-industrial character of the region, with the exception of lung cancer in man. The differences in the O/E ratios for lung cancer among the separate communities indicate that even in the situation of generally lower mortality, the dependence of lung cancer mortality on radon.

  4. Radon gas as a tracer for volcanic processes

    International Nuclear Information System (INIS)

    Thomas, D.M.

    1990-01-01

    Radon emissions from volcanic systems have been under investigation for several decades. Soil gas and groundwater radon activities have been used to map faults and to characterize geothermal systems, and measurements of atmospheric radon and radon daughter concentrations have been used to estimate the volume of magma chambers feeding active eruptions. Several studies have also shown that temporal variations in radon concentration have been associated with the onset of volcanic eruptions or changes in the rates or character of an eruption. Some of these studies have been able to clearly define the cause of the radon anomalies but others have proposed models of radon emission and transport that are not well supported by the known physical and chemical processes that occur in a volcanic system. In order to better characterize the processes that control radon activities in volcanic systems, it is recommended that future radon monitoring programs attempt to maintain continuous recording of radon activities; individual radon measurements should be made over the shortest time intervals possible that are consistent with acceptable counting statistics and geophysical, meteorological, and hydrological parameters should be measured in order to better define the physical processes that affect radon activities in volcanic systems. (author). 63 refs

  5. 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.)

  6. The measurement of airborne rodon daughter concentrations in the atmosphere

    International Nuclear Information System (INIS)

    Ha, C.W.; Lee, J.K.; Moon, P.S.

    1979-01-01

    A simple method for determining the airborne concentration of radon daughter products has been developed, which is based on gross alpha counting of the air filter collections at several time intervals after completion of air sampling. The concentration of each nuclide is then obtained from an equation involving the alpha disintegrations, the sampling time, and the known numerical coefficients. The state of radioactive disequilibrium is also inventigated. The atmosphere sampled in the TRIGA Mark-III reactor room was largely in disequilibrium. The extent of radioactive disequilibrium between radon daughter products seems likely depend on sampling times associated with turbulence conditions. The data obtained here will certainly provide useful information on the evaluation of internal exposure and calibration of effluent monitoring instruments. (author)

  7. Indoor radon

    International Nuclear Information System (INIS)

    1997-12-01

    The radon, a natural radioactive gas, is present almost everywhere on the earth's surface. It can be accumulated at high concentration in confined spaces (buildings, mines, etc). In the last decades many studies conducted in several countries showed that inhaling important amounts of radon rises the risk of lung cancer. Although, the radon is a naturally appearing radioactive source, it may be the subject of a human 'enhancement' of concentration. The increasing radon concentration in professional housing constitutes an example of enhanced natural radioactivity which can induce health risks on workers and public. Besides, the radon is present in the dwelling houses (the domestic radon). On 13 May 1996, the European Union Council issued the new EURATOM Instruction that establishes the basic standards of health protection of population and workers against the ionizing radiation hazards (Instruction 96/29/EURATOM, JOCE L-159 of 29 June 1996). This instruction does not apply to domestic radon but it is taken into consideration by another EURATOM document: the recommendation of the Commission 90/143/EURATOM of 21 February 1990 (JOCE L-80 of 27 March 1990). The present paper aims at establishing in accordance to European Union provisions the guidelines for radon risk management in working places, as well as in dwelling houses, where the implied risk is taken into account. This document does not deal with cases of high radon concentration on sites where fabrication, handling or storage of radium sources take place. These situations must be treated by special studies

  8. Radon compensation for alpha air monitoring systems

    International Nuclear Information System (INIS)

    Fleming, D.M.; Rising, F.L.; Zuerner, L.V.

    1975-01-01

    Continuous alpha air monitors, employing solid state detectors and single channel analyzers, for the detection of alpha particles of a specific energy have been available commercially for several years. The single channel pulse height analyzers provide good sensitivity to the isotope of interest and reject much of the unwanted activity from other isotopes such as naturally occurring radon and daughters. A small percentage of the radon daughters are degraded in energy by the air between the collecting filter and the diode to the extent that they coincide with energy of the isotope being measured and are counted as unwanted background. When 239 Pu is the isotope being measured the activity in the Pu channel resulting from radon is typically 2 percent of the total radon background. The majority of this unwanted background results from the degradation of the 6.0 MeV 218 Po (RaA) peak. This background is sufficient to cause instrument alarms during periods of radon activity. In attempts to reduce the frequency of false alarms, background subtraction circuits have been added as standard equipment to most of the alpha air monitors available on the market for the past several years. A method for calibrating these background subtraction circuits using a radon generator is described. (U.S.)

  9. QA/QC For Radon Concentration Measurement With Charcoal Canister

    International Nuclear Information System (INIS)

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

    2015-01-01

    The primary concern of any measuring of radon or radon progeny must be the quality of the results. A good quality assurance program, when properly designed and diligently followed, ensures that laboratory staff will be able to produce the type and quality of measurement results which is needed and expected. Active charcoal detectors are used for testing the concentration of radon in dwellings. The method of measurement is based on radon adsorption on coal and measurement of gamma radiation of radon daughters. Upon closing the detectors, the measurement was carried out after achieving the equilibrium between radon and its daughters (at least 3 hours) using NaI or HPGe detector. Radon concentrations as well as measurement uncertainties were calculated according to US EPA protocol 520/5-87-005. Detectors used for the measurements were calibrated by 226Ra standard of known activity in the same geometry. Standard and background canisters are used for QA and QC, as well as for the calibration of the measurement equipment. Standard canister is a sealed canister with the same matrix and geometry as the canisters used for measurements, but with the known activity of radon. Background canister is a regular radon measurement canister, which has never been exposed. The detector background and detector efficiency are measured to ascertain whether they are within the warning and acceptance limits. (author).

  10. 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.)

  11. 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

  12. Some reflections on radon and its measurement

    International Nuclear Information System (INIS)

    Becker, K.

    1991-01-01

    A brief editorial considers mainly two problems concerning radon measurement in residential buildings and its possible health effects. The first relates to the reporting in the literature of radon measurements to an accuracy which exceeds the accuracy of the measuring equipment. Secondly in radioepidemiological studies, care should be exercised in equating uranium miners and people living in houses since their working and living conditions are not comparable; this could sometimes explain an apparent lack of detectable negative health effects in residents. (UK)

  13. Radon as a remedy - radiobiological and medical aspects, risk; Radon als Heilmittel - strahlenbiologische und medizinische Aspekte, Risiko

    Energy Technology Data Exchange (ETDEWEB)

    Schwarz, E.R.; Nuernberger, E.; Martignoni, K. [Inst. fuer Strahlenhygiene des Bundesamtes fuer Strahlenschutz, Oberschleissheim/Neuherberg (Germany)

    1995-09-01

    For years there have been controversial discussions about the benefit and risk of radon-balneo-therapy. This is particularly true where the inhalation of radon and its daughter products in curative galleries is concerned. Animal experiments and studies on uranium miners have clearly shown that the exposure with radon and its daughter products is connected with an additional risk for lung cancer. Findings on balneo-therapeutic mechanisms are, at best, incomplete and the topic of controversial discussions in radiobiology. This applies specifically to `hormesis` or `adaptive response`, as indicated in this context. Given the numerous reports of therapeutic results, there appear to be curative effects from radon-balneotherapy for special indications. (orig.) [Deutsch] Nutzen und Risiko der Radon-Balneotherapie werden seit Jahren widerspruechlich diskutiert. Dies gilt insbesondere fuer die Inhalation des Radons und seiner Folgeprodukte in Heilstollen. Tierversuche und Untersuchungen bei Uranbergleuten haben eindeutig gezeigt, dass mit der Exposition durch Radon und seinen Folgeprodukten ein zusaetzliches Lungenkrebsrisiko verbunden ist. Erkenntnisse zum Wirkungsmechanismus der Radon-Balneotherapie liegen allenfalls in Ansaetzen vor und werden in der Strahlenbiologie kontrovers diskutiert. Dies gilt insbesondere fuer die in diesem Zusammenhang angefuehrte `Hormesis` bzw. `Adaptive Response`. Geht man von den zahlreich berichteten therapeutischen Erfahrungen aus, so scheint es Hinweise auf Heileffekte der Radon-Balneotherapie fuer spezielle Indikationen zu geben. (orig.)

  14. 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

  15. Scopingsreport Radon

    NARCIS (Netherlands)

    Blaauboer RO; Vaas LH; Hesse JM; Slooff W

    1989-01-01

    Dit scopingsrapport vormt een onderdeel van de voorbereiding tot het opstellen van het basisdocument radon. Het doel van dit rapport is het algemene kennisniveau van de deelnemers aan de scopingsbijeenkomst aangaande radon op eenzelfde peil te brengen en discussie- en beslispunten inzake de

  16. Project Radon

    International Nuclear Information System (INIS)

    Ekholm, S.

    1988-01-01

    The project started in March 1987. The objective is to perform radon monitoring in 2000 dwellings occupied by people employed by State Power Board and to continue to contribute to the development of radon filters. The project participates in developing methods for radon measurement and decontamination and in adapting the methods to large scale application. About 400 so called radon trace measurements (coarse measurement) and about 10 action measurements (decontamination measurement) have been made so far. Experience shows that methods are fully applicable and that the decontamination measures recommended give perfectly satisfactory results. It is also established that most of the houses with high radon levels have poor ventilation Many of them suffer from moisture and mould problems. The work planned for 1988 and 1989 will in addition to measurements be directed towards improvement of the measuring methods. An activity catalogue will be prepared in cooperation with ventilation enterprises. (O.S.)

  17. A comparison of contemporary and retrospective radon gas measurements in high radon dwellings in Ireland

    International Nuclear Information System (INIS)

    Kelleher, K.; McLaughlin, J.P.; Fenton, D.; Colgan, P.A.

    2006-01-01

    Little correlations has been found between contemporary radon gas measurements made in the past and retrospective radon gas measurements in Irish dwellings. This would suggest that these two techniques would result in two significantly different cumulative radon exposure estimates. Contemporary radon gas measurements made a few years apart in the same room of a dwelling were found to be significantly different. None of these differences could be explained by known changes to the rooms themselves., such ventilation or structural alterations to the room. This highlights the limitations of the contemporary radon gas measurements as a surrogate measurement for use in residential radon epidemiology. The contemporary radon gas measurements made by the Radiological Protection Institute of Ireland (R.P.I.I.) and University College of Dublin (U.C.D.) do not cover the same exposure period as the retrospective estimates and so the accuracy of the retrospective measurements cannot be demonstrated. A weak correlation can be seen between the retrospective radon gas estimates and a combination of the two contemporary radon gas estimates. It is not unreasonable to expect improvement in the correlation if further contemporary radon gas measurements were made in these rooms. (N.C.)

  18. Radiation hazard due to radon in indoor air

    International Nuclear Information System (INIS)

    Keller, G.

    1987-01-01

    Inhalation of the noble gas radon and its short-lived daughter products present in normal room air causes a considerable increase of the mean natural radiation exposure of the population. As there is an uncontested relationship between lung dose and cancer risk, measures should be taken to guarantee that the radon concentrations in room air do at least not reach maxima. The most simple measure is frequent, brief, good ventilation. Very high radon concentrations are measured in houses where radon pentrates direct from the soil into buildings. For this case, radon-tight insulation of the building from the soil is recommended. A forced ventilation system with heat recovery, installed by experts, has shown to be very successful in radon reduction in 'problematic' houses. (orig.) [de

  19. A passive monitor for radon using electrochemical track etch detector

    International Nuclear Information System (INIS)

    Massera, G.E.; Hassib, G.M.; Piesch, E.

    1980-01-01

    A passive, inexpensive monitor for radon detection and dosimetry is described in detail. It consists of a Makrofoil track etch detector inside a diffusion chamber which is sealed by a fibreglass filter through which radon may diffuse while radon daughters and aerosols are retained on the surface of the filter. The α-particle tracks are revealed by etching the Makrofoil in KOH. The lower detection limit of the radon dosimeter is equivalent to a mean dose in the lung of 130 mrem. After an exposure period of 3 months, a mean radon concentration of 0.3 pCi/l can be detected. The instrument is intended for use in a study to measure the long-term radon exposure in buildings in West Germany. (UK)

  20. Radon discrimination for work place air samples

    International Nuclear Information System (INIS)

    Bratvold, T.

    1994-01-01

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

  1. Measurement of Radon concentration in groundwater by technique of nuclear track detector

    International Nuclear Information System (INIS)

    Trinh Van Giap; Nguyen Manh Hung; Dang Duc Nhan

    2000-01-01

    A method for measuring radon concentration in groundwater using nuclear track detector LR-115 stripping is reported. The radon-monitoring device in groundwater is a small box with two pieces of nuclear track detector and all these materials is placed in a plastic bag made by polyethylene. It is very suitable to measure radon concentration in groundwater well in long term. Alpha tracks produced by radon and it daughter on nuclear track detector is counted automatically by spark counting method. The paper also presents some results of radon concentration in some groundwater well and mineral water sources. (author)

  2. Creating Geologically Based Radon Potential Maps for Kentucky

    Science.gov (United States)

    Overfield, B.; Hahn, E.; Wiggins, A.; Andrews, W. M., Jr.

    2017-12-01

    Radon potential in the United States, Kentucky in particular, has historically been communicated using a single hazard level for each county; however, physical phenomena are not controlled by administrative boundaries, so single-value county maps do not reflect the significant variations in radon potential in each county. A more accurate approach uses bedrock geology as a predictive tool. A team of nurses, health educators, statisticians, and geologists partnered to create 120 county maps showing spatial variations in radon potential by intersecting residential radon test kit results (N = 60,000) with a statewide 1:24,000-scale bedrock geology coverage to determine statistically valid radon-potential estimates for each geologic unit. Maps using geology as a predictive tool for radon potential are inherently more detailed than single-value county maps. This mapping project revealed that areas in central and south-central Kentucky with the highest radon potential are underlain by shales and karstic limestones.

  3. World Health Organization's International Radon Project 2005-2008

    International Nuclear Information System (INIS)

    Carr, Zhanat; Shannoun, Ferid; Zielinski, Jan M.

    2008-01-01

    Recent epidemiological studies of people exposed to indoor radon have confirmed that radon in homes is a serious health hazard that can be easily mitigated. To address the issue at an international level, the World Health Organization (WHO) established the International Radon Project (IRP). The project was launched in January 2005 with its first meeting attended by 36 experts representing 17 countries. The project's scope and the key objectives were outlined at this meeting and later refined: 1-) To identify effective strategies for reducing the health impact of radon; 2-) To promote sound policy options, prevention and mitigation programs (including monitoring and evaluation of programs; 3-) To raise public, political and economical awareness about the consequences of exposure to radon (including financial institutions as target group); 4-) To estimate the global health impact of exposure to residential radon using available data on radon worldwide. WHO and its member states strive through the WHO-IRP to succeed in putting indoor radon on the environmental health agenda in countries with lower awareness of radon as a health problem and in strengthening local and national radon-related activities in countries with ongoing radon programs. Two subsequent working meetings were held: in March, 2006 in Geneva with 63 participants from 25 countries, along with representatives of the International Atomic Energy Agency (IAEA), the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), the International Commission on Radiological Protection (ICRP), and European Commission (EC); and in March 2007 in Munich with 61 participants from 27 countries. Both meetings reviewed the IRP progress and focused on the two main outputs: 'The WHO Report on the Global Burden of Disease (GBD) due to Radon' and 'The WHO Radon Handbook'. The former applies the WHO methodology for GBD assessment and considers ways to graphically map residential radon concentrations

  4. Daughters on Hunger Strike

    Directory of Open Access Journals (Sweden)

    Ann Wan-lih Chang

    2008-03-01

    Full Text Available This essay explores the embattled interactions between mothers and daughters in the stories by Edna O’Brien, Mary Lavin, Éilís Ní Dhuibhne and Mary Leland. This conflict involves an underlying distorted intimacy between women within a patriarchal Irish context. The daughter in the stories seeks to rebel against the ‘choking love’ of the tyrannical ‘patriarchal mother’ through a symbolic anorexia, in which the daughter rejects the mother’s food or the food associated with the mother. The mother is also shown to feel ambivalent and resistant towards the daughter’s attempt to break from her dependence upon the mother. The conflict and resistance between mothers and daughters in these stories can be evaluated against the framework of the patriarchal context in which women as mothers are silenced and made powerless in front of the ‘Father,’ and therefore, this resistance can be interpreted as a reaction to this patriarchal ideology and its framework in Irish society. The lost bond between older and younger women needs to be rediscovered and restored by a realisation of patriarchal ideology and furthermore, identification with female subjectivity. This identification between women seems to act as a source of redemption for women of different generations, which results in both liberating themselves from the patriarchal dogma.

  5. Radon as a remedy - radiobiological and medical aspects, risk

    International Nuclear Information System (INIS)

    Schwarz, E.R.; Nuernberger, E.; Martignoni, K.

    1995-01-01

    For years there have been controversial discussions about the benefit and risk of radon-balneo-therapy. This is particularly true where the inhalation of radon and its daughter products in curative galleries is concerned. Animal experiments and studies on uranium miners have clearly shown that the exposure with radon and its daughter products is connected with an additional risk for lung cancer. Findings on balneo-therapeutic mechanisms are, at best, incomplete and the topic of controversial discussions in radiobiology. This applies specifically to 'hormesis' or 'adaptive response', as indicated in this context. Given the numerous reports of therapeutic results, there appear to be curative effects from radon-balneotherapy for special indications. (orig.) [de

  6. Accumulation of radon in the underground detector cups

    International Nuclear Information System (INIS)

    Qiu Yuanhuo.

    1985-01-01

    Theoretical calculations based on the radon migration mechanism (i. e. diffusion, convection and atmospheric pumping etc) show that the balance of radon concentration in underground detector cups buried and in surrounding soil gas requires about 0.7-10 hours. However, the equilibrium of radon with its daughter products in the cups needs about 4 hours. Therefore, it is considered that 4.5-12 hours are needed for these two processes. It takes 3-4 days for Tn to reach radioactive equilibrium with its short-lived daughter products. When thorium concentration is higher than background exposure time of the detector cups should be over 3-4 days. Using buried detector cups, field experiments give correlative results compared with those of theoretical calculations. The study is oriented both for optimizing the burial time of the detector cup and interpretation of radon anomalies detected

  7. A passive monitor for radon using electrochemical track etch detector

    International Nuclear Information System (INIS)

    Massera, G.E.; Hassib, G.M.; Piesch, E.

    1980-01-01

    A passive monitor for radon and its decay products based on the electrochemical etching (ECE) of α-particle tracks on Makrofol is described. The monitor has been constructed in such a way that radon and radon daughters attached to aerosols can easily pass through a chamber while dust, heavy particles and water droplets are collected outside. The decay products are accumulated on the bottom of the chamber and a Makrofol detector foil is fixed on the top to register alpha particles. The ECE condition was maintained to detect alpha particles coming mainly from radon daughters trapped on the bottom of the chamber. The response of the monitor was determined at different exposure conditions and compared with those of some active techniques such as working level meters. The merits of this system are low cost, good sensitivity, portability and reliable, unattended operation. (author)

  8. Radon problems

    International Nuclear Information System (INIS)

    Cohen, B.L.

    1985-01-01

    This chapter examines the health hazards resulting from the release of naturally occurring radioactive gas derived from the decay of uranium. It is estimated that random inhalation is now causing about 10,000 fatal lung cancers per year in the US. Radon is constantly being generated in rocks and soils (in which uranium is naturally present) and in materials produced from them (e.g., brick, stone, cement, plaster). It is emphasized that radon levels in buildings are typically 5 times higher than outdoors because radon diffusing up from the ground below or out of bricks, stone, cement, or plaster is trapped inside for a relatively long time

  9. Exposures to radon and thoron and their decay products. Annex D

    International Nuclear Information System (INIS)

    1982-01-01

    The purpose of this Annex, which has over 400 references, is to provide information about the levels and doses of radon and thoron and their decay products, and about physical parameters influencing and causing these levels and doses. The detrimental effects of radon and thoron daughters are not dealt with in this Annex.

  10. The comparison of doses and risks from radon, medical and accidental irradiation

    International Nuclear Information System (INIS)

    Zhukovskij, M.V.; Yarmoshenko, I.V.; Bayankin, S.N.

    1998-01-01

    The following radiation hazards to the population of the region of Sverdlovsk are compared: the hazard from the exposure to indoor radon in dwellings; the consequences of the radiation accident at the 'Mayak' nuclear power plant in 1957; radioactive contamination by thorium enrichment tails; medical diagnostic exposure. It is concluded that radon and its daughters constitute the most significant radiation hazard. (A.K.)

  11. 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

  12. Measurement Techniques for Radon in Mines, Dwellings and the Environment

    International Nuclear Information System (INIS)

    Snihs, J.O.

    1983-06-01

    Definitions and units appropriate for radon and radon daughters are given. The principle methods of detection are ionization chamber, scintillation technique, nuclear track detector, thermoluminescent discs and alpha spectrometry. The activity concentration is determined by grab sampling and subsequent measurement, frequent or continuous grab sampling and measurement and continuous sampling and long time integrated measurement. Sampling and measurement strategies for mines, dwellings and the environment are discussed. (author)

  13. 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

  14. A detailed study of inexpensive radon control techniques in New York state houses

    International Nuclear Information System (INIS)

    Nitschke, I.A.; Wadach, J.B.; Clarke, W.A.; Traynor, G.W.; Adams, G.P.; Rizzuto, J.E.

    1984-01-01

    As part of a comprehensive indoor air quality and infiltration field study, radon concentrations were measured in 60 houses in upstate New York using passive integrating monitors. Indoor air radon concentrations ranged from 0.2 pCi/l to 50 pCi/l. Four houses with the highest radon levels were then extensively monitored using real-time continuous instruments for the measurement of radon, radon daughters, respirable particles, infiltration, inside-outside pressure difference, and weather parameters. Several inexpensive radon mitigation techniques were tested in these four houses. Their effectiveness ranged widely. Techniques identified as effective were permanently installed in 14 houses having indoor air radon concentration above 2 pCi/l. Finally, the long-term effectiveness of the installed control techniques is being tested using passive integrating radon monitors. (Author)

  15. Effect of ventilation type on radon concentration at places of work

    International Nuclear Information System (INIS)

    Oksanen, E.

    1994-01-01

    Indoor radon ( 222 Rn) concentrations were measured at 76 child care facilities and 36 schools in southern Finland. The buildings had three different types of ventilation systems: mechanical air supply and exhaust, mechanical exhaust, and natural ventilation, the first being most common. The effect of the ventilation type on the long-term radon concentration was studied in child care facilities. The radon concentrations were highest in the naturally ventilated buildings. The mechanical air supply and exhaust system maintained the lowest values in cold wintertime. In school buildings both the long-term radon concentration and short-term radon and daughter concentrations were measured. The correlation of the ventilation type and the radon concentration was not obvious in this group of measurements, but the radon concentrations and the equilibrium factors were highest in buildings with natural ventilation. Radon concentrations were generally lower during the working hours than during the one-month period, as expected. (author)

  16. Radon reduction

    International Nuclear Information System (INIS)

    Hamilton, M.A.

    1990-01-01

    During a radon gas screening program, elevated levels of radon gas were detected in homes on Mackinac Island, Mich. Six homes on foundations with crawl spaces were selected for a research project aimed at reducing radon gas concentrations, which ranged from 12.9 to 82.3 pCi/l. Using isolation and ventilation techniques, and variations thereof, radon concentrations were reduced to less than 1 pCi/l. This paper reports that these reductions were achieved using 3.5 mil cross laminated or 10 mil high density polyethylene plastic as a barrier without sealing to the foundation or support piers, solid and/or perforated plastic pipe and mechanical fans. Wind turbines were found to be ineffective at reducing concentrations to acceptable levels. Homeowners themselves installed all materials

  17. Radon in dwellings in Sweden

    International Nuclear Information System (INIS)

    Swedjemark, G.A.

    1980-01-01

    Studies on specific activities in building materials, gamma-radiation levels in dwellings, the concentrations of radon and daughters in the air indoors and the concentration of radon in tap water are in progress in Sweden. On the basis of these investigations and of the investigation of Hultqvist from the beginning of the 1950's, an attempt has been made to show how the radiation doses in dwellings have changed or may be changed by human activities and what these changes imply in terms of collective dose. The annual collective absorbed dose in the basal cells of the critical bronchial region have increased from 11 x 10 3 man-Gy for the occupants of dwellings existing in 1950 to 25 x 10 3 man-Gy for dwellings existing in 1975

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

    International Nuclear Information System (INIS)

    Harley, N.H.

    1992-01-01

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

  19. The use of an empirical correlation between surface activity and integrated radon exposure in a retrospective radon measurement

    International Nuclear Information System (INIS)

    Cauwels, P.; Poffijn, A.

    1998-01-01

    Retrospective measurements of integrated radon concentration in dwellings over the past decades are dealt with, based on the fact that glass sheets act as a memory for the airborne radon activity due to the implanted 210 Po and 210 Bi activity. The room model established to this purpose by Jacobi in 1972 seems to need some modifications; calculated and measured data suggest the existence of a possible loss of implanted daughter products. (A.K.)

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

    International Nuclear Information System (INIS)

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

    1995-01-01

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

  1. 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

  2. Results of atmospheric radon survey from the tenth Antarctica expedition, 1990-1991

    International Nuclear Information System (INIS)

    Ramachandran, T.V.; Subba Ramu, M.C.; Nambi, K.S.V.

    1992-01-01

    Results of the measurement of atmospheric radon (Rn) levels carried out en route to and from Antarctica and indoor Rn daughter levels at Antarctica are presented in this paper. Grab sampling and integrated methods were used for the measurements. The atmospheric Rn levels are found to decrease steadily from 2400 mBq.m -3 at Goa to 40 mBq.m -3 at the equator. It is found to decrease further to 13 mBq.m -3 towards 70degS. At Maitree station (70degS, 11degE), it varied from 20 to 30 mBq.m -3 . Measured indoor Rn daughter levels (equilibrium equivalent concentration, EEC Rn ) at Maitree station varied from 1.7 Bq.m -3 to 21.3Bq.m -3 in various residential places of the Indian Station. Using ICRP dose conversion factor, the estimated effective dose equivalents range from 0.14 mSv/y to 1.8 mSv/y. (author). 8 refs., 2 tabs

  3. Measurement of the concentration of radon in the air

    International Nuclear Information System (INIS)

    Aten, J.B.Th.; Bierhuizen, H.W.J.; Hoek, L.P. van; Ros, D.; Weber, J.

    1975-01-01

    A simple transportable air monitoring apparatus was developed for controlling the radon contamination of air in laboratory rooms. It is not highly accurate but is sufficient to register the order of magnitude of the radon concentration. Air is pumped through a filter for one or two hours and an alpha decay curve of the dust on the filter is determined. Scintillation counting forty minutes after sampling indicates the radon activity. The calibration method of measuring the equilibrium of daughter product concentrations is discussed extensively

  4. Radon in dwellings and lung cancer - a discussion

    International Nuclear Information System (INIS)

    Stranden, E.

    1980-01-01

    A discussion of the lung cancer risk associated with radon exposure inside dwellings is presented. The risk factors found for miners are discussed and modified according to the lower mean breathing rates inside dwellings and the differences in atmosphere. Statistical information on the lung cancer incidence in the Norwegian population indicates that a 'doubling exposure rate' of radon daughters inside dwellings may be about 2-3 WLM/yr. This corresponds to a radon concentration of about 10-15 pCi/l. These values are used in a discussion of the consequences of a future reduction of the mean ventilation rates in modern houses. (author)

  5. Final report of evaluation of dose and measurement of radon concentration

    International Nuclear Information System (INIS)

    1998-03-01

    A mean annual exposure to radon daughters in indoor air was estimated on the basis of measurement of radon concentration in indoor air in Japan from fiscal 1992 to 1996. Doses were estimated by UNSCEAR method. The representative values in this report show the mean values in whole Japan. Each dose in the local area was different reflecting the different concentration of radon daughters. However, the same parameters were used in each area. When mean annual dose of radon daughters was estimated, we used 15.5 Bq m -3 mean annual exposure to radon daughters in indoor air, 5 Bq m -3 that in outdoor air, 0.4 the equilibrium factor indoor, 0.6 the equilibrium factor outdoor and 0.9 of P. The model of UNSCEAR based on these above values gave 0.46 mSv y -1 mean annual dose of radon daughters which were consisted of from 0.38 mSv y -1 in Kanto district to 0.52 mSv y -1 Kyushu, Okinawa district. (S.Y.)

  6. Final report of evaluation of dose and measurement of radon concentration

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    A mean annual exposure to radon daughters in indoor air was estimated on the basis of measurement of radon concentration in indoor air in Japan from fiscal 1992 to 1996. Doses were estimated by UNSCEAR method. The representative values in this report show the mean values in whole Japan. Each dose in the local area was different reflecting the different concentration of radon daughters. However, the same parameters were used in each area. When mean annual dose of radon daughters was estimated, we used 15.5 Bq m{sup -3} mean annual exposure to radon daughters in indoor air, 5 Bq m{sup -3} that in outdoor air, 0.4 the equilibrium factor indoor, 0.6 the equilibrium factor outdoor and 0.9 of P. The model of UNSCEAR based on these above values gave 0.46 mSv y{sup -1} mean annual dose of radon daughters which were consisted of from 0.38 mSv y{sup -1} in Kanto district to 0.52 mSv y{sup -1} Kyushu, Okinawa district. (S.Y.)

  7. A method for purifying air containing radioactive substances resulting from the disintegration of radon

    International Nuclear Information System (INIS)

    Stringer, C.W.

    1974-01-01

    The invention relates to the extraction of radioactive isotopes from air. It refers to a method for withdrawing the radioactive substances resulting from the disintegration of radon from air, said method of the type comprising filtrating the air contaminated by the radon daughter products in a filter wetted with water in order to trap said substances in water. It is characterized in that it comprises the steps of causing the water contaminated by the radon daughter products to flow through a filtrating substance containing a non hydrosoluble granular substrate, the outer surface of which has been dried then wetted by a normally-liquid hydrocarbon, and of returning then wetted by a normally-liquid hydrocarbon, and of returning the thus filtrated water so that it wets again the air filter and entraps further radon daughter products. This can be applied to the purification of the air in uranium mines [fr

  8. Radon in coal power plant areas

    International Nuclear Information System (INIS)

    Mauna, Traian; Mauna, Andriesica

    2006-01-01

    Radon, the radioactive colourless and inodorous noble gas, represents more than 55% of the natural average radioactivity. It is permanently released from the soil and majority of building materials, it builds up in the mine galleries, in dwelling houses and in other closed rooms. Radon gained increasingly in importance, particularly after 1990 when was doubtless identified as the second cause of lung cancer if a given concentration threshold is surpassed. This threshold is established differentially by each country as a function of the particular site and generally ranges between 150 Bq.m -3 and 600 Bq.m -3 . The telluric radon consists of two isotopes, 222 Rn, a daughter of radium descending from uranium, which induces 90% of the effects, and 220 Rn from thorium series which have too short a lifetime to count in the risk assessments of radon inhalation. The interest of the authorities and population for diminishing the radon effects was illustrated by specific studies which in USA were managed by the National Counsel of Research, the BEIR VI committee of which has issued a report concerning the lung cancer produced by radon and its descendants. Coal mining, the transport, processing, burning, slag and ash disposal are activities entailing radon release. The miners' dwellings are placed in areas with the high radon potential. The local building materials have a high content of radioactive elements from the uranium or thorium series so that radon can build up in the closed rooms of these buildings. Hence the social responsible authorities in the coal power industry zones should consider this aspect long time ignored in the Balkans macro zone so far. The radon issue must be differentially approached in different areas hence a zonal mapping of the radon emission should be first done. It is worth to underline that the gaseous radioactive emission from operational nuclear power plants amounts up to a few percents of the radon natural emissions what entails a

  9. Radon depletion in xenon boil-off gas

    Energy Technology Data Exchange (ETDEWEB)

    Bruenner, S.; Cichon, D.; Lindemann, S.; Undagoitia, T.M.; Simgen, H. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany)

    2017-03-15

    An important background in detectors using liquid xenon for rare event searches arises from the decays of radon and its daughters. We report for the first time a reduction of {sup 222}Rn in the gas phase above a liquid xenon reservoir. We show a reduction factor of >or similar 4 for the {sup 222}Rn concentration in boil-off xenon gas compared to the radon enriched liquid phase. A semiconductor-based α-detector and miniaturized proportional counters are used to detect the radon. As the radon depletion in the boil-off gas is understood as a single-stage distillation process, this result establishes the suitability of cryogenic distillation to separate radon from xenon down to the 10{sup -15} mol/mol level. (orig.)

  10. Realization of a reference system for the generation radon 222

    International Nuclear Information System (INIS)

    Guelin, M.

    1990-11-01

    After some general considerations on radon and its calibration techniques, the methods and technologies developed in order to realize a reference system for the generation of radon 222 are presented. Two original patented techniques have been developed. The former technique deals with the realization of radon 222 solid sources from radium 226 deposit on acrylic fibres. This new technology offers the advantage of very quickly obtaining a constant emission rate near to 100%. The latter technique deals with the standard measurement of radon 222 volumic activity via gamma spectrometry of its short-lived daughters. This new procedure is the only one allowing to relate this measure to gaseous standards. An aeraulic/ventilation circuit makes it possible to calibrate the radon measurement instrumentation within a wide volumic activity range from to 4 to 4 000 Bq/m 3

  11. Intercomparison of different instruments for measuring radon concentration in air

    International Nuclear Information System (INIS)

    Shimo, Michikuni; Iida, Takao

    1990-01-01

    An intercomparison of different instruments for measurement of radon concentration was carried out. The instruments include an ionization chamber, the charcoal-trap method, a flow-type ionization chamber (pulse-counting method), a two-filter method, an electrostatic collection method and a passive integration radon monitor. All instruments except for the passive radon monitor have been calibrated independently. Measurements were performed over a concentration range from about 3.5 Bq·m -3 (in outdoor air) to 110 Bq·m -3 (in indoor air). The results obtained by these techniques, except the two-filter technique, are comparable. Radon daughter concentration measured using a filter-sampling method was about 52% of radon concentration. (author)

  12. Intercomparison of different instruments that measure radon concentration in air

    International Nuclear Information System (INIS)

    Shimo, M.; Iida, T.; Ikebe, Y.

    1987-01-01

    An intercomparison of different instruments for measurement of radon concentration was carried out. The instruments include an ionization chamber, the charcoal-trap technique, a flow-type ionization chamber (pulse-counting technique), a two-filter method, an electrostatic collection method and a passive integrating radon monitor. All instruments except for the passive radon monitor have been calibrated independently. Measurements were performed over a concentration range from about 3.5 Bq/m/sup 3/ (in outdoor air) to 110 Bq/m/sup 3/ (in indoor air). The results obtained from these techniques, except the two-filter technique, are comparable. Radon daughter concentration measured using a filter-sampling technique was about 52% of radon concentrations

  13. Radon in streams and ground waters of Pennsylvania as a guide to uranium deposits

    International Nuclear Information System (INIS)

    Korner, L.A.; Rose, A.W.

    1977-06-01

    Radon-222, a daughter in the radioactive decay of uranium, has potential as a geochemical guide to uranium ores because of its chemical inertness and its relatively easy determination. The radon contents of 59 stream and 149 ground waters have been determined with a newly designed portable radon detector in order to test the method in uranium exploration. Radon contents of stream waters do not appear useful for reconnaissance uranium exploration of areas like Pennsylvania because of relatively rapid degassing of radon from turbulent waters, and because most radon is derived from nearby influx of ground waters into the streams. Radon in streams near uranium occurrences in Carbon and Lycoming counties is lower than many background streams. Radon in ground water is recommended as a reconnaissance method of uranium exploration because most samples from near mineralized areas are anomalous in radon. In contrast, uranium in ground waters is not anomalous near mineralized areas in Carbon County. Equations are derived to show the relation of radon in ground waters to uranium contents of enclosing rocks, emanation of radon from the solids to water, and porosity or fracture width. Limonites are found to be highly enriched in radium, the parent of radon. A model for detection of a nearby uranium ore body by radon measurement on a pumping well has been developed

  14. 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

  15. Calibration of CR-39 plastic detectors in various modes and radon measurement in the north-western region of Bangladesh

    International Nuclear Information System (INIS)

    Islam, G.S.; Islam, M.A.; Haque, A.K.F.

    1998-04-01

    Solid State track detectors have been extensively used for the measurement of time integrated radon levels in dwellings under different conditions. The CR-39 plastic detectors were calibrated for bare as well as cup with membrane mode, along with a mono dispersal aerosol 0.2μm in size in an exposure chamber, to find the relationship between track densities and the radon concentration as well as potential alpha energy concentration (WL) of radon. Measurement of the indoor radon and radon daughter concentrations were performed in houses in the north-western region of Bangladesh. In total 163 detectors were placed for measurement of indoor radon activities and 230 detectors for measurement of radon daughter concentrations. To study the underground radon activity, 114 CR-39 detectors in cylinders were used. The indoor radon activity in Naogaon was, in general, found to be higher than that in Rajshahi. The working levels in the mud-built houses were greater than that in brick-built houses. The underground radon activity of Naogaon was found to be 6 times higher than that of Rajshahi. No direct correlation was observed between the underground and indoor radon activity. The average values of radon activity and the working level for the north-western zone of Bangladesh are found to be 91 Bq. m -3 and 16 mWL respectively. (author)

  16. Aerosol microphysics of indoor radon

    International Nuclear Information System (INIS)

    1989-01-01

    To provide an improved description for the deposition of charge on ultrafine aerosol particles, we have introduced for the first time into aerosol studies the ''jellium'' model potential to quantitatively describe the interaction energy at long range between a conducting particle and an ion (here modeled as a point charge). The benefit of utilizing this potential, in its linearized approximation, is that it accounts for the response of the particle's conduction electrons to the field of the ion rather than relying upon a macroscopic picture whose validity is nuclear for sufficiently small particles. In the limit of large separations or of larger particles, the jellium and image potentials converge rapidly implying that no inconsistency exists between the generally-accepted approach for larger particles and our contribution. As a part of our work, we have given an accurate fit to the experimental data in the literature on the charging rate of neutral particles in the 4--50 nm range of radii without the need for assumptions other than of the charging ion properties. The results of this work will contribute to the ability to model charged radon daughter cluster ion attachment to high-diffusivity particles and conversely to the ability to model charge attachment on high-diffusivity uncharged particles containing a radon daughter

  17. A study of radon levels in the soil of Nasir's College of Agriculture - Yemen

    International Nuclear Information System (INIS)

    Ali, Taher M.; Ahmed, Hayel A.; Zumalian, Abubaker A.

    2000-01-01

    The radon diffusion in the atmosphere and dwelling interior comes from one source, it is the soil. Emitting alpha particles, radon daughters may be deposited in to the lungs and cause health hazards, so for this reason, estimation of radon levels in soil and dwelling were done in may countries. in the present work, we have used the passive dosimeters (SSNTD s ) containing (Cr-39) detectors. The dosimeters were distributed at the surface of the ground, in the soil horizontally (at depth 50 cm) and in soil with depth. The overall mean for radon levels in soil horizontally was (1.28 ± 0.05) KBq/m 3 and the mean radon concentration at the surface of the ground was (0.42 ± 0.03) KBq/m 3 . It is found that radon concentration increases as the depth increases up to (90 cm) depth after that radon levels decrease as the depth increases. (author)

  18. 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)

  19. 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

  20. Statistics and error considerations at the application of SSND T-technique in radon measurement

    International Nuclear Information System (INIS)

    Jonsson, G.

    1993-01-01

    Plastic films are used for the detection of alpha particles from disintegrating radon and radon daughter nuclei. After etching there are tracks (cones) or holes in the film as a result of the exposure. The step from a counted number of tracks/holes per surface unit of the film to a reliable value of the radon and radon daughter level is surrounded by statistical considerations of different nature. Some of them are the number of counted tracks, the length of the time of exposure, the season of the time of exposure, the etching technique and the method of counting the tracks or holes. The number of background tracks of an unexposed film increases the error of the measured radon level. Some of the mentioned effects of statistical nature will be discussed in the report. (Author)

  1. Managing Radon in Schools

    Science.gov (United States)

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

  2. New devices for radon measurements

    International Nuclear Information System (INIS)

    Sevostyanov, V.N.

    2004-01-01

    This work includes the description of two new devices for radon surveys developed by the authors and produced in Kazakhstan. The first appliance is 'Ramon-Radon-01' used to measure 222 Rn radon in various mediums such as air, water, soil, and radon exhalation. The major advantage of the appliance lies in the absence of radioactive pollution in it after measurements. The appliances widely used in the CIS such as 'RAA-01', 'Alpharad' (produced by 'MTM Zaschita', Russia) and 'Alphaguard' (Germany) take samples directly to the measuring camera. For instance, the activity concentration of samples after they are taken by 'RAA-01' and 'Alpharad' is measured by means of electrostatic precipitation of RaA ( 218 Po) atoms to the square of semiconductor detector with subsequent registration of RaA alpha decay. The obvious disadvantage is that the subsequent measurement of relatively small 222 Rn activity concentration values after great values of 222 Rn activity concentration have been obtained requires a considerable exposure of the appliance sometimes exceeding 10 hours. Therefore, appliances register a relatively low value of the top measurement range of 20 KBq/m 3 . 'Alphaguard' has similar limitation resulting from precipitation of radon daughter decay products on the walls of ionizing chamber where radon activity concentration is measured. The radioactive lag of 'RAA-01', 'Alpharad' and 'Alphaguard' makes them of little use as well for automatic monitoring in the conditions of abruptly time negative derivatives on change of radon activity concentration. The second advantage is that 'Ramon-Radon-01', as opposed to above described appliances, registers almost zero radioactive lag, thanks to its constructive peculiarities which enable an abrupt increase of top range of measured value up to 5x10 5 Bq/m 3 , only limited by velocity of electron units of the appliance. The third advantage is that measurement discontinuity is determined only by time of full measurement cycle

  3. The finnish guide to radon-resistant homes

    International Nuclear Information System (INIS)

    Arvela, H.

    2006-01-01

    Full text of publication follows: New regulations of the National Finnish Building Code require consideration of radon risks and as a main rule radon technical design in the building permission documents. Slab-on-grade is the prevalent substructure in Finnish low-rise residential buildings. Building statistics show that the prevalent practices in foundation construction promote the flow of radon-bearing soil air into living spaces. Without prevention the normal practices would result in high indoor radon concentrations in Finland. In wide areas more than 50% of houses exceed the reference level of 200 Bq/m 3 given for new buildings. The new guide published in 2003 requires installation of protective sheet in the slab-on-ground foundation and a preparatory radon piping. A protective sheet of durable reinforced bitumen felt with a width of 50 - 100 cm should be installed in the slab-foundation wall joint. Careful sealing of lead-troughs plays also an important role. In the case the sealing work does not result in low indoor radon concentration, the radon piping should be activated through radon-fan installation. Careful implementation of the sealing work reduces indoor radon concentration to a level of less than 50 Bq/m 3 , also in areas where the normal building practices result in indoor radon concentrations exceeding the reference level of 200 Bq/m 3 in more than 50% of new houses. Recent experiences from the implementation of the guide will be considered. (author)

  4. Randon daughter exposure of the U.K. population

    International Nuclear Information System (INIS)

    Cliff, K.D.

    1980-01-01

    The highest dose to the body tissues from natural radioactivity is that to the bronchial epithelium arising predominantly from the short-lived daughters of 222 Rn with a lesser contribution from the daughters of 220 Rn. This paper discusses the estimation of current United Kingdom population exposure to these nuclides. At present the exposure for an average member of the population of the UK is 0.15 WLM y -1 when the winter ventilation rate is 0.8 h -1 . This will increase to 0.58 WLM y -1 if the winter ventilation rate is reduced to 0.2 h -1 . The use of electrostatic precipitators would decrease the measured WL but would not affect the unattached fraction of 222 Rn daughter products, which determines the dose to the epithelium. Other methods of reducing 222 Rn daughter concentrations under investigation include prevention of the ingress of 222 Rn from the subsoil and the coating of construction materials with a radon barrier

  5. Functional test of a Radon sensor based on a high-resistivity-silicon BJT detector

    Energy Technology Data Exchange (ETDEWEB)

    Dalla Betta, G.F., E-mail: dallabe@disi.unitn.it [DISI, Università di Trento, and INFN Trento, Trento (Italy); RSens srl, Modena (Italy); Tyzhnevyi, V. [DISI, Università di Trento, and INFN Trento, Trento (Italy); Bosi, A.; Bonaiuti, M. [RSens srl, Modena (Italy); Angelini, C.; Batignani, G.; Bettarini, S.; Bosi, F.; Forti, F.; Giorgi, M.A.; Morsani, F.; Paoloni, E.; Rizzo, G.; Walsh, J. [Dipartimento di Fisica, Università di Pisa, and INFN Pisa, Pisa (Italy); Lusiani, A. [Scuola Normale Superiore and INFN Pisa, Pisa (Italy); Ciolini, R.; Curzio, G.; D' Errico, F.; Del Gratta, A. [Dipartimento di Ingegneria Meccanica, Nucleare e della Produzione, Università di Pisa, Pisa (Italy); Bidinelli, L. [En and tech, Università di Modena e Reggio Emilia, Reggio Emilia (Italy); RSens srl, Modena (Italy); and others

    2013-08-01

    A battery-powered, wireless Radon sensor has been designed and realized using a BJT, fabricated on a high-resistivity-silicon substrate, as a radiation detector. Radon daughters are electrostatically collected on the detector surface. Thanks to the BJT internal amplification, real-time α particle detection is possible using simple readout electronics, which records the particle arrival time and charge. Functional tests at known Radon concentrations, demonstrated a sensitivity up to 4.9 cph/(100 Bq/m{sup 3}) and a count rate of 0.05 cph at nominally-zero Radon concentration.

  6. Diurnal measurement of equilibrium equivalent radon/thoron concentration using time integrated flow mode grab sampler

    International Nuclear Information System (INIS)

    Pant, P.; Kandari, T.; Ramola, R.C.; Semwal, C.P.; Prasad, M.

    2018-01-01

    The basic processes which influenced the concentration of radon and thoron decay products are- attachment, recoil and deposition and by the room specific parameters of radon exhalation and ventilation. The freshly formed decay products have a high diffusivities (especially in air) and ability to stick to surfaces. According to UNSCEAR 1977, radon daughters may be combined as the so called equilibrium equivalent concentration which is related to the potential alpha energy distribution concentration. In the present study an effort has been made to see the diurnal variation of radon and thoron progeny concentration using time integrated flow mode sampler

  7. 30 CFR 57.5037 - Radon daughter exposure monitoring.

    Science.gov (United States)

    2010-07-01

    ... Floor, New York, NY 10036; http://www.ansi.org. The mine operator may request that the required exhaust..., haulageways, shops, stations, lunch rooms, magazines, and any other place or location where persons work...

  8. Radon Daughters Background Reduction in Alpha Particles Counting System

    International Nuclear Information System (INIS)

    Dadon, S. S.; Pelled, O.; Orion, I.

    2014-01-01

    The ABPC method is using a serially occurring events of the beta decay of the 214Bi fallow by alpha decay of the 214Po that take place almost simultaneously to detect the Pseudo Coincidence Event (PCE) from the RDP, and to subtract them from the gross alpha counts. 267 This work showed that it is possible to improve the efficiency of RDP background reduction, including subtracting the 218Po contribution by using the ABPC method based on a single solid state silicon PIPS detector. False counts percentage obtained at the output of the PCE circuit were smaller than 0.1%. The results show that the PCE circuit was not influenced by non RDP alpha emitters. The PCE system did not reduce the non PCE of the 218Po. After 20 minutes the 218Po was strongly decayed, and its contribution became negligible. In order to overcome this disadvantage, a mathematical matching calculations for the 214Po and the 218Po decay equations were employed, and a constant ratio of the APo214(0) / APo218(0) was obtained. This ratio can be used to estimate the count rate of the 218Po at the first 20 minutes, and to subtract it from the total count rate in order to obtain correct RDP reduction

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

    Energy Technology Data Exchange (ETDEWEB)

    Schlenker, R.A.

    1984-08-15

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

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

    International Nuclear Information System (INIS)

    Schlenker, R.A.

    1984-01-01

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

  11. Measurement of airborne radon daughters - a Bayesian approach

    International Nuclear Information System (INIS)

    Groer, P.G.; Lo, Y.

    1997-01-01

    The standard mathematical treatment of the build-up and decay of airborne radionuclides on a filter paper uses the solutions of the so-called Bateman equations adapted to the sampling process. These equations can be interpreted as differential equations for the expectation of an underlying stochastic process, which describes the random fluctuations in the accumulation and decay of the sampled radioactive atoms. The probability distribution for the number of 218 Po, 214 Pb and 214 Bi atoms, accumulated after sampling time t, is the product of three Poisson distributions. It is shown that the distribution of the number of counts, registered by a detector with efficiency ε during a counting period T after the end of sampling, is also the product of three Poisson distributions. Its mean is dependent on ε, t, T, flow rate, and N A 0 , N B 0 and N C 0 , the number of 218 Po, 214 Pb and 214 Bi atoms per unit volume. This joint Poisson distribution was used to construct the likelihood given the observed number of counts. Using Bayes' Theorem posterior densities were obtained for N A 0 , N B 0 and N C 0 . These densities characterise the remaining uncertainty about the unknown airborne concentrations of 218 Po, 214 Pb and 214 Bi atoms. (author)

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

    International Nuclear Information System (INIS)

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

    2008-01-01

    We test whether airborne gamma ray spectrometer measurements can be used to estimate levels of radon hazard in the Oslofjord region of Norway. We compile 43,000 line kilometres of gamma ray spectrometer data from 8 airborne surveys covering 10,000 km 2 and compare them with 6326 indoor radon measurements. We find a clear spatial correlation between areas with elevated concentrations of uranium daughters in the near surface of the ground and regions with high incidence of elevated radon concentrations in dwellings. This correlation permits cautious use of the airborne data in radon hazard evaluation where direct measurements of indoor radon concentrations are few or absent. In radon hazard evaluation there is a natural synergy between the mapping of radon in indoor air, bedrock and drift geology mapping and airborne gamma ray surveying. We produce radon hazard forecast maps for the Oslofjord region based on a spatial union of hazard indicators from all four of these data sources. Indication of elevated radon hazard in any one of the data sets leads to the classification of a region as having an elevated radon hazard potential. This approach is inclusive in nature and we find that the majority of actual radon hazards lie in the assumed elevated risk regions

  13. 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

  14. BGS Radon Protective Measures GIS

    International Nuclear Information System (INIS)

    Appleton, D.; Adlam, K.

    2000-01-01

    The British Geological Survey Radon Protective Measures Geographical Information System is described. The following issues are highlighted: Identification of development sites where radon protection is required in new dwellings; Mapping radon potential on the basis of house radon and geology; Radon Protective Measures GIS; Radon site reports; and Follow-up radon protective measures sire reports

  15. Systematic effects in radon mitigation by sump/pump remediation

    International Nuclear Information System (INIS)

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

    2006-01-01

    Sump/Pump remediation is widely used in the United Kingdom to mitigate indoor radon gas levels in residential properties. To quantify the effectiveness of this technology, a study was made of radon concentration data from a set of 173 homes situated in radon Affected Areas in and around Northamptonshire, U.K., re-mediated using conventional sump/pump technology. This approach is characterised by a high incidence of satisfactory mitigation outcomes, with more than 75% of the sample exhibiting mitigation factors (defined as the ratio of radon concentrations following and prior to remediation) of 0.2 or better. There is evidence of a systematic trend, where houses with higher initial radon concentrations have higher mitigation factors, suggesting that the total indoor radon concentration within a dwelling can be represented by two components, one susceptible to mitigation by sump/pump remediation, the other remaining essentially unaffected by these remediation strategies. The first component can be identified with ground-radon emanating from the subsoil and bedrock geologies, percolating through the foundations of the dwelling as a component of the soil-gas, potentially capable of being attenuated by sump/pump or radon-barrier remediation. The second contribution is attributed to radon emanating from materials used in the construction of the dwelling, principally concrete and gypsum plaster-board, with a further small contribution from the natural background level, and is essentially unaffected by ground-level remediation strategies. Modelling of such a two-component radon dependency using realistic ground-radon attenuation factors in conjunction with typical structural-radon levels yields behaviour in good agreement with the observed inverse-power dependence of mitigation factor on initial radon concentration. (authors)

  16. Environmental radon monitoring in Khartoum dwellings

    International Nuclear Information System (INIS)

    Mohamed, I. S.

    1992-03-01

    Radon is a naturally occurring radioactive gas that is released into the surrounding environment. Existence of this gas indoors ( house and dwelling ) mainly depends on its source in the building materials, the soil beneath the buildings and the ventilation of the rooms. In this study the technique of ground activated charcoal and gamma spectrometry system are used for Radon measurement. This technique has been calibrated and optimized. The main reason for radon determination in house comes from the fact that Radon and its daughters are directly responsible of lung cancer and some kidney diseases. The measurements, in this study, have been performed for Khartoum indoors. 644 rooms have been measured. These rooms were sorted out into groups according to their building material as well as the ventilation of each room. The measurements covered the whole year ( the three main seasons ) to see the variation of Radon level, since its emanation is affected by the temperature. Also monthly outdoor measurements have been performed in different locations in Khartoum. On the basis of the results obtained, the radiation dose received by the public due to the inhalation of this gas has been calculated. The average annual effective dose was found to be 1.2 m Sv. (author). 33 refs., 17 tabs., 24 figs

  17. Radon and its decay products in housing

    International Nuclear Information System (INIS)

    Swedjemark, G.A.

    1985-01-01

    Methods have been worked out for evaluation of the uncertainties due to temporal variations in the annual averages for the concentrations of radon-222 (radon) and radon daughters (RnD) indoors. These methods have been applied to the results from long-term measurements of radon in a few houses. The possible use of correction factors in order to get a more adequate annual average have also been studied and some examples have been given. On the basis of country-wide investigations carried out during 1955-56 and during 1972-75 averages of the radon concentrations in housing existing in 1950 and 1975 were calculated six years ago to be 29 and 71 Bq m -3 respectively. A new country-wide investigation with the aim of obtaining values representative for the country was carried out during 1980-82. On the basis of these results a new calculation was made of the concentrations in dwelllings existing in 1975 to 101 Bq m -3 and also for the 1980 housing stock to 98 Bq m -3 . These results are discussed and the collective dose equivalents in the Swedish population have been calculated. (author)

  18. Radon measurements with a PIN photodiode

    International Nuclear Information System (INIS)

    Martin-Martin, A.; Gutierrez-Villanueva, J.L.; Munoz, J.M.; Garcia-Talavera, M.; Adamiec, G.; Iniguez, M.P.

    2006-01-01

    Silicon photodiodes are well suited to detect alphas coming from different sources as neutron reactions or radon daughters. In this work a radon in air detecting device, using an 18x18 mm silicon PIN photodiode is studied. The ionized airborne decay products formed during radon diffusion were focused by an accelerating high voltage to the PIN surface. Several conducting rings were disposed inside a cylindrical PVC vessel in such a way that they reproduced the electric field created by a punctual charge located behind PIN position. Alpha spectra coming from the neutral and ionized species deposited on the PIN surface, dominated by 218 Po and 214 Po progeny peaks, were recorded for varying conditions. Those include radon concentration from a Pylon source, high voltage (thousands of volts) and PIN inverse bias voltage. Different parameters such as temperature and humidity were also registered during data acquisition. The increase in the particle collection efficiency with respect to zero electric field was compared with the corresponding to a parallel plates configuration. A discussion is made in terms of the most appropriate voltages for different radon concentrations

  19. Sampling strategies for indoor radon investigations

    International Nuclear Information System (INIS)

    Prichard, H.M.

    1983-01-01

    Recent investigations prompted by concern about the environmental effects of residential energy conservation have produced many accounts of indoor radon concentrations far above background levels. In many instances time-normalized annual exposures exceeded the 4 WLM per year standard currently used for uranium mining. Further investigations of indoor radon exposures are necessary to judge the extent of the problem and to estimate the practicality of health effects studies. A number of trends can be discerned as more indoor surveys are reported. It is becoming increasingly clear that local geological factors play a major, if not dominant role in determining the distribution of indoor radon concentrations in a given area. Within a giving locale, indoor radon concentrations tend to be log-normally distributed, and sample means differ markedly from one region to another. The appreciation of geological factors and the general log-normality of radon distributions will improve the accuracy of population dose estimates and facilitate the design of preliminary health effects studies. The relative merits of grab samples, short and long term integrated samples, and more complicated dose assessment strategies are discussed in the context of several types of epidemiological investigations. A new passive radon sampler with a 24 hour integration time is described and evaluated as a tool for pilot investigations

  20. 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.

  1. 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

  2. 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)

  3. Development of a data base on radon in US homes and applications. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, B.L.

    1991-12-31

    This research led to the development of the compilation of data on radon in homes which is included in this document. This research also contributed to the development of two papers analyzing the results. These are a case control study test and tests of the liner no-threshold theory for lung cancer induced by exposure to radon in residential buildings.

  4. Development of a data base on radon in US homes and applications

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, B.L.

    1991-01-01

    This research led to the development of the compilation of data on radon in homes which is included in this document. This research also contributed to the development of two papers analyzing the results. These are a case control study test and tests of the liner no-threshold theory for lung cancer induced by exposure to radon in residential buildings.

  5. 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

  6. Radon concentrations in some Egyptian dwellings using LR 115 detectors

    Energy Technology Data Exchange (ETDEWEB)

    Hussein, A S [Radiation Protection Department, Nuclear Power Plants Authority, Cairo (Egypt)

    2007-06-15

    Radon, a well-established risk factor for human lung cancer, is present at low concentrations in most homes. Consequently, many countries have established national guidelines for residential radon concentrations. This survey provides additional information about indoor radon concentrations in Egypt. Indoor radon survey of a total of 15 randomly selected houses in Qena city, Upper Egypt was carried out. LR 115 detectors were exposed for one year, covering all the seasons. The estimated indoor radon levels varied from 19 to 59 Bq m{sup 3} with an average of 40 Bq m{sup 3}. Using the bare and filtered LR 115 detectors, the average equilibrium factor F was assessed as 0.30 indoors. An average annual effective dose of 0.40 mSv has been estimated and was found to be lower than the ICRP-65.

  7. Radon and lung cancer among New Jersey women

    International Nuclear Information System (INIS)

    Schoenberg, J.; Klotz, J.; Wilcox, H.; Nicholls, G.

    1990-01-01

    An epidemiologic study previously conducted in New Jersey women was extended to examine the association of lung cancer with radon exposure. The substudy included 433 cases and 402 controls who lived in a single index residence for 10+ years during the period 10--30 years prior to diagnosis or selection. Lung cancer risks showed a significant trend (p = 0.04) with increasing year-round living area radon concentrations (based on alpha track measurements), and a weaker (p = 0.09) trend with estimated cumulative radon exposure. The relative risk coefficient of 3.4% per working level month (WLM) was consistent with the range of 0.5--4%/WLM generally reported for underground miners. This paper results must be interpreted cautiously due to the small number of subjects with high radon exposures and the possibility of selection biases. Nevertheless, the study suggests that findings of radon-related lung cancer in miners can be applied to the residential setting

  8. Radon concentrations in some Egyptian dwellings using LR 115 detectors

    International Nuclear Information System (INIS)

    Hussein, A.S.

    2007-01-01

    Radon, a well-established risk factor for human lung cancer, is present at low concentrations in most homes. Consequently, many countries have established national guidelines for residential radon concentrations. This survey provides additional information about indoor radon concentrations in Egypt. Indoor radon survey of a total of 15 randomly selected houses in Qena city, Upper Egypt was carried out. LR 115 detectors were exposed for one year, covering all the seasons. The estimated indoor radon levels varied from 19 to 59 Bq m 3 with an average of 40 Bq m 3 . Using the bare and filtered LR 115 detectors, the average equilibrium factor F was assessed as 0.30 indoors. An average annual effective dose of 0.40 mSv has been estimated and was found to be lower than the ICRP-65

  9. 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

  10. Radon in homes and other technologically enhanced radioactivity

    International Nuclear Information System (INIS)

    Rundo, J.; Toohey, R.E.

    1983-01-01

    The results are described of recent observations at Argonne National Laboratory, contributing to our knowledge of such factors as the origin of high levels of radon in houses, its variability with time or otherwise, its uniformity throughout the house or otherwise, and the behavior and fate of the short-lived daughter-products. In a sample of 110 houses, mostly in the west suburban area of Chicago, 15% had radon concentrations in excess of 6 pCi litre - 1 and 96% greater than 10 pCi litre - 1 . If this distribution is representative of all houses in the USA, the population being exposed to such high concentrations of radon is far greater than the number of people in Grand Junction being exposed to quite similar concentrations from technologically enhanced radioactivity. There is a great need for far more extensive data on radon in houses

  11. 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)

  12. Radon and its hazards

    International Nuclear Information System (INIS)

    Chang Guilan

    2002-01-01

    The author describes basic physical and chemical properties of radon and the emanation, introduces methods of radon measurement, expounds the hazards of non-mine radon accumulation to the health of human being and the protection, as well as the history how the human being recognizes the hazards of radon through the specific data and examples, and finally proposes protecting measures to avoid the hazards of radon to the health of human being, and to do ecologic evaluation of environments

  13. Radon: current challenges in cellular radiobiology

    International Nuclear Information System (INIS)

    Brenner, D.J.

    1992-01-01

    Most of what is known about the hazards of radon daughters comes from epidemiological studies of miners. There are a few well defined areas in which in vitro research can complement such studies: More data on the relative effects of differing energy (LET) α-particles would help: (1) understand the significance of the depth of sensitive cells in the bronchial epithelium-which varies between individuals, as well as between smokers and non-smokers, and between miners and non-miners; (2) understand the relative hazards of radon and thoron daughters. Reliable methods for predicting high LET responses from low LET response, would enable Japanese A-bomb survivor data to be applied with confidence. Understanding the effects of single-particle traversals of cells relative to multiple traversals could allow reliable extrapolation of epidemiological miner data to low exposures. A better understanding of the nature of the interaction between tobacco and radiation damage would help predict the effect of radon on non-smokers. (author)

  14. Design and application of a continuous, digital-output, environmental radon measuring instrument

    International Nuclear Information System (INIS)

    Spitz, H.; Wrenn, M.E.

    1977-01-01

    A radon measuring instrument has been developed which can continuously measure environmental concentrations of radon in the atmosphere without employing any air movers or pumps. The unit is entirely passive in design and relies upon the diffusion of radon for sample collection. Since radon is an inert noble gas it will follow the classical theory of motion and diffuse in a direction dependent upon the concentration gradient existing between the atmosphere and the sensitive portion of the detector. A porous foam filter allows radon, but not its daughters, to enter the detector where an electrostatic field is maintained to facilitate collection of the decay products of radon, i.e., initially the positive ions of RaA (Po-218). Alpha particles from RaA and RaC' (Po-214) within the sensitive volume are detected using a ZnS scintillator and photomultiplier tube with the usual complement of electronics

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

    International Nuclear Information System (INIS)

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

    2015-01-01

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

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

    Science.gov (United States)

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

    2015-08-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Street, J., E-mail: joseph.street@mines.sdsmt.edu; Bunker, R.; Dunagan, C.; Loose, X.; Schnee, R. W.; Stark, M.; Sundarnath, K.; Tronstad, D. [Department of Physics, South Dakota School of Mines & Technology, Rapid City, SD 57701 (United States)

    2015-08-17

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

  18. Improved radon-flux-measurement system for uranium-tailings pile measurement

    International Nuclear Information System (INIS)

    Freeman, H.D.

    1981-10-01

    The Pacific Northwest Laboratory (PNL) is developing cover technology for uranium mill tailings that will inhibit the diffusion of radon to the atmosphere. As part of this cover program, an improved radon flux measurement system has been developed. The radon measurement system is a recirculating, pressure-balanced, flow-through system that uses activated carbon at ambient temperatures to collect the radon. With the system, an area of 0.93 m 2 is sampled for periods ranging from 1 to 12 h. The activated carbon is removed from the radon trap and the collected radon is determined by counting the 214 Bi daughter product. Development of the system included studies to determine the efficiency of activated carbon, relative calibration measurements and field measurements made during 1980 at the inactive tailings pile in Grand Junction, Colorado. Results of these studies are presented

  19. Radon prevention in new construction. Sample survey 2009

    International Nuclear Information System (INIS)

    Arvela, H.; Maekelaeinen, I.; Holmgren, O.; Reisbacka, H.

    2010-05-01

    The building code for radon prevention and the associated practical guidelines were revised in Finland in 2003 to 2004. Thereafter, preventive measures have become more common and prevention practices more effective. Consequently, indoor radon concentrations in new construction have been markedly reduced. In this study, the indoor radon concentration was measured in 1 500 new lowrise residential houses. The houses were randomly selected and represented 7 % of houses that received building permission in 2006. The average radon concentration of all houses measured, which were completed in 2006 to 2008, was 95 Bq/m 3 , the median being 58 Bq/m 3 . The average was 30 % lower than in houses completed in 2000 to 2005. The decrease was 50 % in provinces with the highest indoor radon concentration and 20 % elsewhere in the country. In houses with a slab-on-ground foundation that had both passive radon piping and sealing measures carried out using a strip of bitumen felt in the joint between the foundation wall and floor slab, the radon concentration was on average reduced by 55 % compared to houses with no preventive measures. Preventive measures were taken in 50 % of single family houses, and in provinces with the highest radon concentration in 90 % of houses. Active prevention in areas with high indoor radon concentrations has reduced the regional differences in the radon concentration. Slab on ground is the prevailing type of foundation and necessitates careful radon prevention measures throughout the country. The most serious defects were observed in prevention practices in houses with walls made of lightweight concrete blocks that were in contact with soil. The foundation types with the lowest radon concentrations were those with a crawl space and a monolithic slab. (orig.)

  20. Indoor radon concentration and outdoor/indoor pressure difference correlation

    International Nuclear Information System (INIS)

    Cechak, T.; Fronka, A.; Moucka, L.

    2004-01-01

    In the current approach to the radon issue, the radon risk for people living in a building is estimated based on the average indoor radon concentration. Short-term measurements as usually applied fail to reflect the wide range of radon variations arising from ventilation, radon supply and, in particular, human activities in the building. For this reason, efforts are made to find a new approach to the assessment of the quality of a building as a radon barrier, independent of the weather conditions and residential habits. A simple model of radon volume activity entering the building at a constant rate and simultaneously ventilated at a constant rate is applicable to this task. The rate of radon ingress can be regarded as a parameter making it possible to quantify the leakage of structures provided the barrier against the radon in a soil gas. The ventilation rate, on the other hand, characterizes the leakage of the whole building envelope at a given outdoor/indoor pressure difference. A unique measuring technique called the blower door exists whereby a defined pressure difference between the indoor and outdoor atmosphere can be established. Under such conditions both the ventilation rate and the rate of radon ingress can be measured and expressed as a function of the pressure difference. An analysis of the model of a room with a constant ventilation and constant radon supply is presented and the relationship between radon supply and ventilation rate can be assumed. Some experimental results show how the model can be utilized. The real indoor-outdoor air pressure differences, the indoor-soil air pressure differences, and some effects of different ventilation regimes are given. Other experiments, which have been done by using the blower door method, illustrate the possible effects and some restrictions for a routine application are discussed