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Sample records for radon progeny measurements

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

    International Nuclear Information System (INIS)

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

    1996-01-01

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

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

    International Nuclear Information System (INIS)

    Akber, R.A.; Harris, F.

    1994-01-01

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

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

    International Nuclear Information System (INIS)

    Efendi, Z.; Jennings, P.

    1993-01-01

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

  4. Indoor thoron and radon progeny measurements

    International Nuclear Information System (INIS)

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

    1992-01-01

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

  5. 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)

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

    International Nuclear Information System (INIS)

    Zhang Lei; Liu Cuihong; Guo Qiuju

    2008-01-01

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

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

    International Nuclear Information System (INIS)

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

    1989-01-01

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

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

    International Nuclear Information System (INIS)

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

    1999-01-01

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

  9. Measurements of radon progeny activity on typical indoor surfaces

    International Nuclear Information System (INIS)

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

    1992-01-01

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

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

    International Nuclear Information System (INIS)

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

    2010-01-01

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

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

    International Nuclear Information System (INIS)

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

    1995-12-01

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

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

    International Nuclear Information System (INIS)

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

    1994-01-01

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

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

    International Nuclear Information System (INIS)

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

    2015-01-01

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

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

    International Nuclear Information System (INIS)

    Zhang Huaiqin; Su Jingling; Yao Wanyuan; Liu Jinhua

    1989-01-01

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

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

    International Nuclear Information System (INIS)

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

    1998-01-01

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

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

    International Nuclear Information System (INIS)

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

    1996-10-01

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

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

    International Nuclear Information System (INIS)

    Janica, R.

    1996-07-01

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

  18. Interaction of radon progeny with atmospheric aerosols

    International Nuclear Information System (INIS)

    Morawska, Lidia

    1994-01-01

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

  19. Development of a portable radon progeny monitor

    International Nuclear Information System (INIS)

    Iimoto, Takeshi; Kosako, Toshiso; Sugiura, Nobuyuki

    2000-01-01

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

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

    International Nuclear Information System (INIS)

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

    1991-01-01

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

  1. Bronchial dosimeter for radon progeny

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-05-01

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

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

    International Nuclear Information System (INIS)

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

    1986-01-01

    Levels of radon and its short-lived airborne progeny are being measured in a year-long study of 70 houses in four states in the Tennessee Valley. Various methods were used to solicit volunteers with differing degrees of success. Criteria for selection of houses in the study included presence of a lower level with cement floor and one or more block walls in contact with the soil, absence of obvious indications of technologically enhanced sources of radium, and proximity to one of four cities, (Knoxville, Chattanooga, Birmingham, or Florence). By design, most houses in the study are in the same neighborhood as at least one other house in the study. Houses range in age from newly constructed to about 40 years old. Most of the houses have more than 2000 square feet of finished floor space. The lower level encompasses a garage in most cases. More complete information pertaining to house characteristics will be gathered in the course of the study. Measurements are being made to obtain information on both location- and season-dependent variation of radon and radon progeny. Simultaneous measurements are made quarterly on both upper and lower levels of each house. Grab samples of air are collected and analyzed for radon using a modified Lucas cell technique. Short-term (10-minute) samples of airborne particulate material are collected and analyzed for radon progeny. One-week integrated measurements of working levels are made once each quarter using modified thermoluminescent dosimeters. Both three- and twelve-month integrated measurements of radon using track-etch monitors are being made. 19 references, 1 figures

  3. Radon Progeny in Egyptian Underground Phosphate Mines

    International Nuclear Information System (INIS)

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

    2001-01-01

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

  4. Control of indoor radon and radon progeny concentrations

    International Nuclear Information System (INIS)

    Sextro, R.G.

    1985-05-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-05-15

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

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

    International Nuclear Information System (INIS)

    Chutima Kranrod; Supitcha Chanyotha; Nares Chankow

    2013-01-01

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

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

    International Nuclear Information System (INIS)

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

    1990-01-01

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

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

    International Nuclear Information System (INIS)

    Boulaud, D.; Chouard, J.C.

    1992-01-01

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

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

    International Nuclear Information System (INIS)

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

    1990-01-01

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

  10. A radon progeny deposition model

    International Nuclear Information System (INIS)

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

    2010-01-01

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

  11. A Radon Progeny Deposition Model

    International Nuclear Information System (INIS)

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

    2011-01-01

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

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

    International Nuclear Information System (INIS)

    Kerr, G.D.

    1975-07-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Acena, M L; Crespo, M T

    1989-07-01

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

  14. 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.

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

    Directory of Open Access Journals (Sweden)

    Mehta Vimal

    2016-01-01

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

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

    International Nuclear Information System (INIS)

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

    1996-01-01

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

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

    International Nuclear Information System (INIS)

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

    1986-01-01

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

  18. Health effects of inhaled radon progeny

    International Nuclear Information System (INIS)

    Monchaux, G.

    1997-01-01

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

  19. 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

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

    International Nuclear Information System (INIS)

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

    2010-01-01

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

  1. Dosimetry of inhaled radon and thoron progeny

    International Nuclear Information System (INIS)

    James, A.C.

    1994-06-01

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

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

    International Nuclear Information System (INIS)

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

    1992-01-01

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

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

    International Nuclear Information System (INIS)

    Marley, F.

    2000-01-01

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

  4. Radon progeny mitigation using unipolar ion generators

    International Nuclear Information System (INIS)

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

    2006-01-01

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

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

    International Nuclear Information System (INIS)

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

    1998-01-01

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

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

    International Nuclear Information System (INIS)

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

    2014-01-01

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

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

    International Nuclear Information System (INIS)

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

    1995-02-01

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

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

    International Nuclear Information System (INIS)

    Estrada, Julio Jose da Silva

    1994-01-01

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

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

    International Nuclear Information System (INIS)

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

    1998-01-01

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

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

    International Nuclear Information System (INIS)

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

    1999-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-03-21

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

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

    International Nuclear Information System (INIS)

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

    2010-01-01

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

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

    Czech Academy of Sciences Publication Activity Database

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

    2016-01-01

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

  14. Concentration ratio of radon progeny in air

    International Nuclear Information System (INIS)

    Kobayashi, Tsuneo

    2000-01-01

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

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

    International Nuclear Information System (INIS)

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

    1997-01-01

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

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

    Science.gov (United States)

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

    2009-08-01

    The quantitative relationships between radon gas concentration, the surface-deposited activities of various radon progeny, the airborne radon progeny dose rate, and various residential environmental factors were investigated through actual field measurements in 38 selected Iowa houses occupied by either smokers or nonsmokers. Airborne dose rate was calculated from unattached and attached potential alpha energy concentrations (PAECs) using two dosimetric models with different activity-size weighting factors. These models are labeled Pdose and Jdose, respectively. Surface-deposited 218Po and 214Po were found significantly correlated to radon, unattached PAEC, and both airborne dose rates (p fireplace, or usage of a ceiling fan significantly, or marginally significantly, reduced the Pdose to 0.65 (90% CI 0.42-0.996), 0.54 (90% CI 0.28-1.02), and 0.66 (90% CI 0.45-0.96), respectively. For Jdose, only the usage of a ceiling fan significantly reduced the dose rate to 0.57 (90% CI 0.39-0.85). In smoking environments, deposited 218Po was a significant negative predictor for Pdose (RR 0.68, 90% CI 0.55-0.84) after adjusting for long-term 222Rn and environmental factors. A significant decrease of 0.72 (90% CI 0.64-0.83) in the mean Pdose was noted, after adjusting for the radon and radon progeny effects and other environmental factors, for every 10 additional cigarettes smoked in the room. A significant increase of 1.71 in the mean Pdose was found for large room size relative to small room size (90% CI 1.08-2.79) after adjusting for the radon and radon progeny effects as well as other environmental factors. Fireplace usage was found to significantly increase the mean Pdose to 1.71 (90% CI 1.20-2.45) after adjusting for other factors.

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

    Energy Technology Data Exchange (ETDEWEB)

    Canoba, A C; Lopez, F O

    1999-07-01

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

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

    International Nuclear Information System (INIS)

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

    1996-01-01

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

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

    Czech Academy of Sciences Publication Activity Database

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

    2008-01-01

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

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

    International Nuclear Information System (INIS)

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

    1984-02-01

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

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

    International Nuclear Information System (INIS)

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

    2000-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Haninger, T

    1998-12-31

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Haninger, T.

    1997-12-31

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

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

    International Nuclear Information System (INIS)

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

    2012-01-01

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

  5. 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)

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

    International Nuclear Information System (INIS)

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

    2015-01-01

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

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

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

    International Nuclear Information System (INIS)

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

    1992-01-01

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

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

    Science.gov (United States)

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

    2009-01-01

    The quantitative relationships between radon gas concentration, the surface-deposited activities of various radon progeny, the airborne radon progeny dose rate, and various residential environmental factors were investigated through actual field measurements in 38 selected Iowa houses occupied by either smokers or nonsmokers. Airborne dose rate was calculated from unattached and attached potential alpha energy concentrations (PAECs) using two dosimetric models with different activity-size weighting factors. These models are labeled Pdose and Jdose, respectively. Surface-deposited 218Po and 214Po were found significantly correlated to radon, unattached PAEC, and both airborne dose rates (p fireplace, or usage of a ceiling fan significantly, or marginal significantly, reduced the Pdose to 0.65 (90% CI 0.42–0.996), 0.54 (90% CI 0.28–1.02) and 0.66 (90% CI 0.45–0.96), respectively. For Jdose, only the usage of a ceiling fan significantly reduced the dose rate to 0.57 (90% CI 0.39–0.85). In smoking environments, deposited 218Po was a significant negative predictor for Pdose (RR 0.68, 90% CI 0.55–0.84) after adjusting for long-term 222Rn and environmental factors. A significant decrease of 0.72 (90% CI 0.64–0.83) in the mean Pdose was noted, after adjusting for the radon and radon progeny effects and other environmental factors, for every 10 increasing cigarettes smoked in the room. A significant increase of 1.71 in the mean Pdose was found for large room size relative to small room size (90% CI 1.08–2.79) after adjusting for the radon and radon progeny effects as well as other environmental factors. Fireplace usage was found to significantly increase the mean Pdose to 1.71 (90% CI 1.20–2.45) after adjusting for other factors. PMID:19590273

  10. Measurements of equilibrium factor between radon and its progeny by using of SSNTD and quality assurance

    International Nuclear Information System (INIS)

    Nikezic, D.

    2009-01-01

    In this paper, a critical survey of existing methods for equilibrium factor determination by using SSNTD is given. An original method, developed by Nikezic and Yu [11,12], that is based on application of LR115 detector is presented. New introduced quantity, so called, proxy factor, that is measurable with LR115 detector, is well correlated with equilibrium factor. (author) [sr

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

    International Nuclear Information System (INIS)

    Zhang Huaiqin; Yao Wanyuan; Su Jingling; Liu Jinhua

    1990-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-12-01

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

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

    International Nuclear Information System (INIS)

    Khan, A.; Phillips, C.R.

    1987-01-01

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

  14. Standardization of radon measurements

    International Nuclear Information System (INIS)

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

    1988-01-01

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

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

    International Nuclear Information System (INIS)

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

    1998-01-01

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

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

    International Nuclear Information System (INIS)

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

    1990-01-01

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

  17. 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

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

    International Nuclear Information System (INIS)

    Gong, S.L.

    1993-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1994-12-31

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

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

    International Nuclear Information System (INIS)

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

    2001-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-02-25

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

  2. Lung dosimetry for inhaled radon progeny

    International Nuclear Information System (INIS)

    Hofmann, W.

    1986-01-01

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

  3. Radon progeny distribution in cylindrical diffusion chambers

    International Nuclear Information System (INIS)

    Pressyanov, Dobromir S.

    2008-01-01

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

  4. Deposition of radon progeny in nonhuman primate nasal airways

    International Nuclear Information System (INIS)

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

    1992-01-01

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

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

    International Nuclear Information System (INIS)

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

    2012-01-01

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

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

    CERN Document Server

    Steck, D J

    1999-01-01

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

  7. Microdosimetry of radon progeny: Application to risk assessment

    International Nuclear Information System (INIS)

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

    1990-01-01

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

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

    Science.gov (United States)

    Wołoszczuk, Katarzyna; Skubacz, Krystian

    2018-01-01

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

  9. Unattached fraction of radon progeny in Polish coal mines

    International Nuclear Information System (INIS)

    Skubacz, K.; Michalik, B.

    2002-01-01

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

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

    International Nuclear Information System (INIS)

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

    1993-06-01

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

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

    International Nuclear Information System (INIS)

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

    2002-01-01

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

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

    Science.gov (United States)

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

    2014-01-01

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

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

    International Nuclear Information System (INIS)

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

    2014-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-08-15

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

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

    International Nuclear Information System (INIS)

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

    1991-01-01

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

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

    International Nuclear Information System (INIS)

    He Quan; Xiong Zhaoxing; He Zuan; Zheng Youqing

    1993-01-01

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

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

    International Nuclear Information System (INIS)

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

    1994-01-01

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

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

    International Nuclear Information System (INIS)

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

    2003-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Prasad Ganesh

    2010-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-02-15

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

  1. External gamma exposure to radon progeny in indoor air

    International Nuclear Information System (INIS)

    Fujimoto, Kenzo

    1985-01-01

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

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

    International Nuclear Information System (INIS)

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

    1993-01-01

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

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

    International Nuclear Information System (INIS)

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

    2015-01-01

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

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

    Science.gov (United States)

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

    2015-11-01

    Characteristics of radon and its progeny were investigated in different air conditions by turning four types of indoor air appliances on and off in a two-story concrete Japanese dwelling. The four appliances were air conditioner, air cleaner, gas heater and cooker hood. The measurements were done using two devices: (1) a Si-based semiconductor detector for continuous measurement of indoor radon concentration and (2) a ZnS(Ag) scintillation counting system for equilibrium-equivalent radon concentration. Throughout the entire experiment, the cooker hood was the most effective in decreasing indoor radon concentration over a long period of time and the less effective was the air conditioner, while the air cleaner and gas heater did not affect the concentration of radon. However, the results measured in each air condition will differ according to the lifestyles and activities of the inhabitants. In this study, indoor radon and its progeny in a Japanese dwelling will be characterised by the different air conditions. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

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

    International Nuclear Information System (INIS)

    Kemal Uzun, Sefa; Demiroez, Isik

    2016-01-01

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

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

    International Nuclear Information System (INIS)

    Castleman, A.W. Jr.

    1996-01-01

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

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

    International Nuclear Information System (INIS)

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

    2006-01-01

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

  8. Lung Deposition And Biological Effects Of Inhaled Radon Progenies

    International Nuclear Information System (INIS)

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

    2010-01-01

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

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

    Science.gov (United States)

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

    2016-10-01

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

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

    Directory of Open Access Journals (Sweden)

    Wołoszczuk Katarzyna

    2018-01-01

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

  11. Lung dosimetry for inhaled radon progeny in smokers

    International Nuclear Information System (INIS)

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

    2010-01-01

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

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

    International Nuclear Information System (INIS)

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

    1984-01-01

    Eleven portable air cleaing devices have been evaluated for control of indoor concentrations of respirable particles, and their concomitant effects on radon progeny concentrations have been investigated. Of the devices we examined the electrostatic precipitators and extended surface filters had significant particle removal rates, while the particle removal rates for several small panel-filters, an ion-generator, and a pair of mixing fans were found to be negligible. The evaluation of radon progeny control produced similar results; the air cleaners which were effective in removing particles were also effective in reducing radon progeny concentrations. Futhermore, at the low particle concentrations, plateout of the unattached radon progeny was found to be a significant removal mechanism. The overall removal rates due to deposition of attached and unattached progeny have been estimated from these data, and the equilibrium factors for total and unattached progeny concentrations have been calculated as a function of particle concentration. (Author)

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

    International Nuclear Information System (INIS)

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

    1984-02-01

    Eleven portable air cleaning devices have been evaluated for control of indoor concentrations of respirable particles, and their concomitant effects on radon progeny concentrations have been investigated. Of the devices we examined the electrostatic precipitators and extended surface filters had significant particle removal rates, while the particle removal rates for several small panel-filters, an ion-generator, and a pair of mixing fans were found to be negligible. The evaluation of radon progeny control produced similar results; the air cleaners which were effective in removing particles were also effective in reducing radon progeny concentrations. Furthermore, at the low particle concentrations, plateout of the unattached radon progeny was found to be a significant removal mechanism. The overall removal rates due to deposition of attached and unattached progeny have been estimated from these data, and the equilibrium factors for total and unattached progeny concentrations have been calculated as a function of particle concentration. 7 references, 2 figures

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

    Energy Technology Data Exchange (ETDEWEB)

    Tokonami, Shinji

    2000-01-01

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

  15. 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

  16. Development of a standard for indoor radon measurements in Australia

    International Nuclear Information System (INIS)

    O'Brien, R.S.; Solomon, S.B.

    1994-01-01

    A standard covering methodologies for the measurement of indoor radon and radon progeny concentrations in air in Australian buildings is currently under preparation as part of a set of standards covering total indoor air quality. This paper outlines the suggested methodology for radon and discusses some of the problems associated with the development of the standard. The draft standard recommends measurement of the radon concentration in air using scintillation cells, charcoal cups and solid state nuclear track detectors, and measurement of radon progeny concentration in air using the Rolle method or the Nazaroff method. 14 refs., 1 tab

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

    International Nuclear Information System (INIS)

    Mayya, Y.S.

    2008-01-01

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

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

    International Nuclear Information System (INIS)

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

    1988-01-01

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

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

    International Nuclear Information System (INIS)

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

    1984-11-01

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

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

    International Nuclear Information System (INIS)

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

    2009-01-01

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

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

    International Nuclear Information System (INIS)

    Kraus, W.; Schwedt, J.

    2002-01-01

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

  2. 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)

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

    International Nuclear Information System (INIS)

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

    2015-01-01

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

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

    International Nuclear Information System (INIS)

    Langner, G.H. Jr.

    1987-06-01

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

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

    International Nuclear Information System (INIS)

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

    2000-01-01

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

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

    International Nuclear Information System (INIS)

    Fujinami, Naoto

    2009-01-01

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

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

    International Nuclear Information System (INIS)

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

    1980-01-01

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

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

    International Nuclear Information System (INIS)

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

    2015-10-01

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

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

    International Nuclear Information System (INIS)

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

    1992-01-01

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

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

    International Nuclear Information System (INIS)

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

    1990-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Estrada, Julio Jose da Silva

    1994-07-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Estrada, Julio Jose da Silva

    1994-07-01

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

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

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

    International Nuclear Information System (INIS)

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

    1992-01-01

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

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

    International Nuclear Information System (INIS)

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

    2018-01-01

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

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

    International Nuclear Information System (INIS)

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

    1989-01-01

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

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

    International Nuclear Information System (INIS)

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

    1994-01-01

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

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

    International Nuclear Information System (INIS)

    Dezsoe, Z.

    2004-01-01

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

  19. Radon flux measurement methodologies

    International Nuclear Information System (INIS)

    Nielson, K.K.; Rogers, V.C.

    1984-01-01

    Five methods for measuring radon fluxes are evaluated: the accumulator can, a small charcoal sampler, a large-area charcoal sampler, the ''Big Louie'' charcoal sampler, and the charcoal tent sampler. An experimental comparison of the five flux measurement techniques was also conducted. Excellent agreement was obtained between the measured radon fluxes and fluxes predicted from radium and emanation measurements

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

    International Nuclear Information System (INIS)

    Papp, Z.

    2006-01-01

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

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

    International Nuclear Information System (INIS)

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

    1996-01-01

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

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

    Science.gov (United States)

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

    2015-04-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Hopke, P.K.

    1992-07-01

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

  4. 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)

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

    International Nuclear Information System (INIS)

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

    2010-01-01

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

  6. Radon and its measurement

    International Nuclear Information System (INIS)

    Penzo, Silvia

    2006-03-01

    The work reviews the topics concerning the problem of the indoor radon and its measurement. The initial stage deals with the general features of radon, from the historical remarks about its discovery to the formation mechanisms in the soil, then passing to describe the transport processes that lead the radon to enter into the buildings. The mean radon concentration distribution among the Italian regions is reported and compared with the situation in the other countries of the world. A particular importance is given to present the national law concerning the radioprotection from the natural sources of ionizing radiations; a paragraph is completely devoted to this argument and to discuss the differences between the Italian approach and the regulations applied in the Test of Europe for both workplaces and dwellings. Chapter 3 describes the different detectors and methods to measure the radon and its short mean live decay products concentrations, together with the operative procedures and guides provided by the Italian law and by the international bodies. As an example of typical radon passive measurement device. the new ENEA detector developed at the Institute of Radioprotection is presented and discussed. Appendix 1 is entirely devoted to discuss the main remedial actions for decreasing the radon indoor concentration both for old and new buildings; appendix 2 reports the main quantities related to radon and radioprotection [it

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

    Science.gov (United States)

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

    2013-03-01

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

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

    International Nuclear Information System (INIS)

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

    1994-01-01

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

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

    International Nuclear Information System (INIS)

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

    2015-01-01

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

  10. Measurements of radon in soil gas

    International Nuclear Information System (INIS)

    Paschuk, Sergei A.; Correa, Janine Nicolosi; Schelin, Hugo R.; Barbosa, Laercio; Sadula, Tatyana; Matsuzaki, Cristiana A.

    2009-01-01

    Full text: After the decades of systematic and numerous studies performed at different countries of the World, it has been concluded that radon as well as its progeny is the main cause of lung cancer. It is well known that more than 50% of the effective annual radiation dose received by a human being is related to the radon and its progenies. Among the principle mechanisms that bring the radon inside the dwelling is the soil exhalation as well as exhalation and release from the water. Radon concentration in the soil and its transport (emanation, diffusion, advection and adsorption) to the surface depends on different physical, geological and ambient parameters such as the geology of the area, geochemical composition of the soil, its porosity and permeability, grain size, soil humidity, bottom sediments and inputs from streams, temperature, atmospheric pressure, etc. Since the main part of indoor radon originates in the soil, the measurements of radon concentration in soil gas have to be considered as an important tool and indicator of probable high levels of radon inside the dwellings. Present work describes the radon in soil gas measurements performed during the last two years in cooperation between the Laboratory of Applied Nuclear Physics of the Federal University of Technology (UTFPR), the Nuclear Technology Development Center (CDTN) and the Institute of Radiation Protection and Dosimetry (IRD) from the Brazilian Nuclear Energy Commission (CNEN). Following previously concluded measurements of radon concentration in dwellings and the measurements of 222 Rn activity in drinking water collected at artesian bores of Curitiba urban area, present step of activities has been dedicated to measurements of radon concentration in soil gas. Experimental setup was based on the Professional Radon Monitor (ALPHA GUARD) connected to specially developed for such measurements Soil Gas Probe through the air pump and filter system. The equipment was adjusted with air flow of 0

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

    Energy Technology Data Exchange (ETDEWEB)

    Hopke, P.K.

    1992-07-01

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

  12. Measuring your radon risk

    International Nuclear Information System (INIS)

    Mackmurdo, R.

    1994-01-01

    In its annual report for 1992/93, the NRPB has warned that tens of thousands of UK employees may be exposed to high levels of radon at work. In addition to those who work underground, employees at risk of radon-induced lung cancer are typically those who spend long periods indoors. This article reviews the implications for all employers especially those in low or unknown levels of radon who resist taking measurements in the belief that by not measuring, they are not liable. (UK)

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

    International Nuclear Information System (INIS)

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

    1994-01-01

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

  14. Sources and protective measures of indoor radon

    International Nuclear Information System (INIS)

    Gou Quanlu; Wang Hengde

    1993-01-01

    This paper presents the relative contribution to indoor radon 222 Rn of various sources in twenty three rooms of three kinds in Taiyuan area. The results show that the major sources in this area are radon emanation from surfaces of soil and building materials and that from outdoor air, while the contribution of water and gas consumed in the rooms is less important. These results suggest a basis for taking suitable protective measures against indoor radon. Some materials are also recommended which are effective in restraining radon exhalation and low in price, by testing more than ten kinds of materials and comparing them using cost-effectiveness analysis technique, such as painting materials, polyvinyl alcohol (CH 2 :CHOH)n, etc. Their sealing effects on radon exhalation were examined with home-made REM-89 Radon Exhalation Monitor. The deposition effects of negative ion generator and humidifier on radon progeny were also tested. The maximum deposition may reach 70-90%, which proves they are also effective and economical in radon protection. (2 tabs., 3 figs.)

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

    International Nuclear Information System (INIS)

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

    2009-01-01

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

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

    International Nuclear Information System (INIS)

    Hopke, P.K.

    1996-09-01

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

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

    International Nuclear Information System (INIS)

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

    1989-01-01

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

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

    International Nuclear Information System (INIS)

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

    1997-01-01

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

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

    International Nuclear Information System (INIS)

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

    2004-01-01

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

  20. Measurement of size distribution for 220Rn progeny attached aerosols

    International Nuclear Information System (INIS)

    Zhang Lei; Guo Qiuju; Zhuo Weihai

    2008-01-01

    The size distribution of radioactive aerosols is a very important factor for evaluating the inner exposure dose contributed by radon and thoron progeny in environments. In order to measure the size distribution of thoron progeny attached radioactive aerosols, a device was developed using wire screens. The count median diameter (CMD) and the geometric standard deviation (GSD) of attached radioactive aerosols were calculated by collecting ThB and using CR-39 as detector. Field measurement results at Yangjiang City in Guangdong Province show that the CMDs distribute between 30 and 130 nm, and the GSDs are between 1.9 and 3.3. It also shows that the more humid country, the smaller CMDs, and the ventilation has great influence on the size distribution of aerosols. The CMDs of adobe house are smaller than that of the concrete houses. (authors)

  1. Indoor radon measurements and methodologies in Latin American countries

    International Nuclear Information System (INIS)

    Canoba, A.; Lopez, F.O.; Arnaud, M.I.; Oliveira, A.A.; Neman, R.S.; Hadler, J.C.; Iunes, P.J.; Paulo, S.R.; Osorio, A.M.; Aparecido, R.; Rodriguez, C.; Moreno, V.; Vasquez, R.; Espinosa, G.; Golzarri, J.I.; Martinez, T.; Navarrete, M.; Cabrera, I.; Segovia, N.; Pena, P.; Tamez, E.; Pereyra, P.; Lopez-Herrera, M.E.; Sajo-Bohus, L.

    2001-01-01

    According to the current international guidelines concerning environmental problems, it is necessary to evaluate and to know the indoor radon levels, specially since most of the natural radiation dose to man comes from radon gas and its progeny. Several countries have established National Institutions and National Programs for the study of radon and its connection with lung cancer risk and public health. The aim of this work is to present the indoor radon measurements and the detection methods used for different regions of Latin America (LA) in countries such as Argentina, Brazil, Ecuador, Mexico, Peru and Venezuela. This study shows that the passive radon devices based on alpha particle nuclear track methodology (NTM) is one of the more generalized methods in LA for long term indoor radon measurements, CR-39, LR-115 and Makrofol being the more commonly used detector materials. The participating institutions and the radon level measurements in the different countries are presented in this contribution

  2. Radiation doses from radon and progeny in Irish houses

    International Nuclear Information System (INIS)

    McLaughlin, J.P.

    1985-08-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-11-11

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

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

    International Nuclear Information System (INIS)

    Streil, T.; Oeser, V.

    2002-01-01

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

  5. Calibration of SSNDT detectors for radon measurements

    International Nuclear Information System (INIS)

    Takahashi, Laura C.; Santos, Talita O.; Pinheiro, Rose Mary M.; Rocha, Zildete

    2017-01-01

    The methods and instrumentation used to measure the concentration of radon need to be calibrated to obtain accurate results. The Nuclear Track Detector is considered the main method of analysis of radon research. Thus, the Natural Radioactivity Laboratory of the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG, Brazil) uses the detector CR-39 (Landauer) to measure the concentration of radon in homes, workplaces, underground mines, soils and in environment. Epidemiological studies reveal the strong relationship between lung cancer and radon exposure. Therefore, it is important to monitor this gas and its progeny in order to assess the radiological risk. The alpha particles emitted by radon and its progeny leave traces on CR-39 due to Coulombian interactions with the atoms of the material. The liquid density of traces is converted to radon concentration by means of a calibration factor obtained in calibrated systems. This work aims to determine the LRN / CDTN calibration factor. To do so, the CR-39 detectors were placed inside the calibration chambers, along with two AlphaGUARD (Saphymo GmbH) detectors and Ra-266 sources with activities of 3,379 kBq or 0.483 kBq, referenced by NIST. From this, six levels of exposure were obtained, which were: 44 kBq.d.m 3 , 4 kBq.d.m 3 , 3 kBq.d.m 3 , 15 kBq.d.m 3 , 30 kBq.d.m 3 , 26 kBq.d.m 3 . The conversion factor between the liquid density of traces and the total exposure time obtained was K = 52.028 ± 0.752 [(trace density.cm -2 ) / (kBq.d.m -3 )]. After the determination of the conversion factor, it was used to measure the concentration of radon in underground mines, obtaining concentration results between 122 ± 24 and 7384 ± 517 kBq.m -3

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

    International Nuclear Information System (INIS)

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

    2016-01-01

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

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

    Science.gov (United States)

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

    2016-10-01

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

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

    International Nuclear Information System (INIS)

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

    2013-01-01

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

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

    International Nuclear Information System (INIS)

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

    2001-01-01

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

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

    International Nuclear Information System (INIS)

    Yamasaki, K.; Shimo, M.

    1992-01-01

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

  11. Integrating measurements of indoor thoron and its progeny concentrations

    International Nuclear Information System (INIS)

    Zhuo, W.H.; Iida, T.; Hashiguchi, Y.

    2000-01-01

    In recent years, indoor surveys in Europe and Asia revealed that the dose contribution from thoron and its progeny can equal or even exceed that of radon and its progeny. For measuring thoron and its progeny, several methods had been reported. However, convenient, low-cost and time-integrating measuring methods which are suitable for large-scale surveys are still unavailable. To solve this problem, three integrating measuring methods with allyl diglycol carbonate plastic (CR-39) as detectors have recently been. The results indicated that they are suitable for estimating the indoor thoron and its progeny concentrations when the public exposure to thoron and its progeny is taken into account. Cup monitor - Former types of passive integrating 222 Rn and 220 Rn cup monitors had been reported. Recently, in order to improve the sensitivity of thoron detection, the air exchange rate between the inner and outer cup was enhanced, and the radius of the hemisphere was reduced to 37.5 mm. Furthermore, the procedure of detector exchange was made to be more convenient. Equilibrium-equivalent 222 Rn and 220 Rn concentrations monitor (EEC monitor) - The measuring system is composed of a monitor head and a diaphragm pump. The total weight of the system is less than 1.5 kg, which makes it portable. The construction of the monitor head and the measuring principle were also reported by the authors. Thoron progeny deposition rate monitor - The monitor is simply constituted a piece of CR-39 covered with thin sheets of absorbers. The thickness of the absorbers are adjusted to let only the α particles emitted from 212 Pb impinge on the detector. The concentrations of thoron progeny are estimated from the deposition rates, assuming that the deposition velocities of thoron progeny are constant in general dwellings. The improved cup monitor has higher sensitivity than former monitors, with a calibration factor of 1.59x10 -3 tracks·cm -2 (Bq·m -3 ·h) -1 for thoron. The accuracy of the ECC

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-07-01

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

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

    International Nuclear Information System (INIS)

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

    1988-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-10-15

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

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

    International Nuclear Information System (INIS)

    Ding Jiansong; Nie Jihua; Tong Jian

    2006-01-01

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

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

    Science.gov (United States)

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

    2016-04-01

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

  17. Airborne radon-222 measurement by active sampling with charcoal adsorption and gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Shizuma, Kiyoshi; Wen, Xiao-qiong; Fukami, Kenji; Iwatani, Kazuo; Hamanaka, Shun-ichi

    1998-01-01

    A simple method for measuring radon concentration in air is presented. Airborne radon is adsorbed in a charcoal bed by an active air sampling. In time, the adsorbed radon comes to attain radioactive equilibrium with its short-lived progeny 214 Pb. Utilizing this fact, radon concentration is derived from γ-ray measurement of 214 Pb. This method is estimated to be capable of detecting radon concentration in air down to 0.79 Bq·m -3 . The adsorption coefficient obtained with the method is compared with what is obtainable with passive sampling. Applications of this method to indoor and outdoor radon measurements are described. (author)

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

    International Nuclear Information System (INIS)

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

    2003-01-01

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

  19. 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).

  20. 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)

  1. 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)

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

    International Nuclear Information System (INIS)

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

    2013-01-01

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

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

    International Nuclear Information System (INIS)

    Abu-Jarad, F.; Fazal-ur-Rehman

    2003-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-07-01

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

  5. 220Radon (Thoron) and progeny exposures in the front-end of nuclear fuel cycle activities with special reference to radioactive minerals, thorium and rare earths processing

    International Nuclear Information System (INIS)

    Pillai, P.M.B.

    2008-01-01

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

  6. Development of a portable instantaneous soil radon measurement instrument

    International Nuclear Information System (INIS)

    Wang Yushuang; Ge Liangquan; Jiang Haijing; Lin Yanchang

    2007-01-01

    A dual-channel instantaneous soil radon measurement instrument based on the method of electrostatic collection is designed. It has the features of small size, low cost, and high sensitivity, etc. A single chip microcomputer is adopted as the data processing and control unit. The concentration of radon can be reported in field. The result is also corrected by the pressure sensing system. A double channel discriminator is used so that the detector can eliminate the interference from the progenies of radon except RaA. LCD and MCU based encoding keyboard are used to give users a friendly interface. Operating and function setting is easy. (authors)

  7. Measuring radon in the workplace

    International Nuclear Information System (INIS)

    Boyd, M.

    1990-01-01

    The Environmental Protection Agency (EPA) has issued guidance for testing for radon in homes and interim guidance for testing in schools. Information on testing for radon in the workplace is the next initiative and this paper describes the current status of this effort. The results of measurements made in several buildings in the Washington, DC area are discussed. In this paper a discussion of preliminary guidance on radon survey design that has been offered to Federal agencies is presented

  8. 210Pb in bone in vivo - a biodosimeter for assessing uranium miner radon progeny exposure

    International Nuclear Information System (INIS)

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

    2002-01-01

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

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

    International Nuclear Information System (INIS)

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

    1978-01-01

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

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

    International Nuclear Information System (INIS)

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

    2006-01-01

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

  11. Air radon equilibrium factor measurement in a Waste Water Pre-Treatment Plant

    International Nuclear Information System (INIS)

    Martinez, J.E.; Juste, B.; Ortiz, J.; Martorell, S.; Verdu, G.

    2017-01-01

    We analyze in this paper a Waste Water Pre-Treatment Plant (WWTP) located at the Mediterranean coast with air radon concentration above Spanish action level (600 Bq per cubic meter). This paper presents a method for radon equilibrium determination by gamma spectrometry measuring of the radon progeny concentrations in the air, in order to estimate WWTP workers effective dose more exactly. The method is based on simultaneous sampling of air through a filter paper and alpha spectrometry measurement of radon activity concentration in the air. According to the measured radon activity concentration in the air of 368±45 Bq/m 3 the equilibrium factor between radon and progenies is estimated to be F=0.27, which is in good agreement with expected values. - Highlights: • High levels of Radon in a workplace can increase health risks in the employees. • Using the typical equilibrium factor 0.4 could lead to an error in the estimation of radon doses. • We present a method for radon equilibrium determination. • Equilibrium factor is calculated by gamma spectrometry measuring of radon progeny concentrations in the air.

  12. 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

  13. Radon measurements in indoor workplaces

    International Nuclear Information System (INIS)

    Tokonami, S.; Matsumoto, M.; Furukawa, M.; Fujimoto, K.; Fujitaka, K.; Pan, J.; Kurosawa, R.

    1996-01-01

    Radon measurements in several office buildings located in Tokyo were carried out with two types of device to study the time-dependent radon concentration in indoor workplaces. Both types of device use the electrostatic field for the collection of 218 Po onto the electrode of the detector. One provides an average radon concentration throughout the day. The other, in which a weekly timer is installed in the circuit of the electrode of the device, provides an average radon concentration during working hours (9:00-17:00, Monday-Friday). Although radon concentrations in Japanese dwellings have been found to be generally low, relatively high concentrations were observed in the office buildings. No consistent seasonal variation was recognised in this study. Little difference of average radon concentrations between working hours and the whole day was found throughout the year in two offices. On the other hand, a significant difference was observed in other offices. The operation of an air conditioner might change the radon concentration during working hours. From the results of radon measurements the average effective dose in the workplace was estimated to be 0.23 mSv for 2000 working hours in a year. (Author)

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

    Energy Technology Data Exchange (ETDEWEB)

    Hopke, P.K.

    1993-01-01

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

  15. Age-dependent lung dosimetry of radon progeny

    International Nuclear Information System (INIS)

    Hofmann, W.; Martonen, T.B.; Menache, M.G.

    1988-02-01

    Two morphometric models differing in the tracheobronchial region, were compared in the present paper: Model 1 is based on the adult morphology of Weibel, assuming that all bronchial airways grow in equal proportion; while Model 2 adopts the adult structure proposed by Yeh and Schum, using measured airway dimensions in the right upper lobe as a function of age. Tidal volume and respiratory frequency also vary with age: while the breathing frequency decreases with rising age, tidal volume increases. Radiation doses in each bronchial airway generation were computed for the deep lying basal cells as well as for the more uniformly distributed serous (SMGS) cells, which are currently assumed to be the progenitor cells for bronchial carcinomas. Radiation doses to both target cells were significantly higher in the newborn than in the adult, for all simulated breathing patterns, showing the highest relative increase in upper bronchial airways. Comparing both tracheobronchial growth models, Model 1 predicts higher doses at early ages, but produced lower doses in the adult lung

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

    International Nuclear Information System (INIS)

    Hofmann, Werner; Fakir, Hatim; Pihet, Pascal

    2007-01-01

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

  17. Measurement of unattached aerosols of 222 Rn progeny by means of an electrostatic deposition method

    International Nuclear Information System (INIS)

    Canoba, Analia C.; Lopez, Fabio O.

    2001-01-01

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

  18. Radon measurements in hispaniola dwellings

    International Nuclear Information System (INIS)

    Gutierrez, J.; Colgan, P.A.; Cancio, D.

    1996-01-01

    The results of a national radon survey and a number of regional surveys of radon in spanish dwelling are reviewed. The best estimate of the geometric mean of indoor radon concentrations is 41.1. Bq/m -3 and single-family dwellings have been shown to be more at risk than apartments. Results need to be interpreted with some caution due to differences in survey methodologies and measurement procedures. The risks from radon exposure are put in perspective by comparison with other voluntary risks. Finally, although a number of 'high risk' areas have already been identified, it is concluded that implementation of a national programme to reduce radon exposure may await a better definition of the problem extent. (authors). 20 refs., 1 tab

  19. Radon integral measurement system

    International Nuclear Information System (INIS)

    Garcia H, J.M.

    1994-01-01

    The Radon Integral Measurement System (SMIR) is a device designed specially to detect, to count and to store the data of the acquisition of alpha particles emitted by Radon-222 coming from the underground. The system includes a detection chamber, a radiation detector, a digital system with bateries backup and an auxiliary photovoltaic cell. A personal computer fixes the mode in which the system works, transmitting the commands to the system by the serial port. The heart of the system is a microprocesor working with interrupts by hardware. Every external device to the microprocessor sends his own interrupt request and the microprocessor handles the interrupts with a defined priority. The system uses a real time clock, compatible with the microprocessor, to take care of the real timing and date of the acquisition. A non volatile RAM is used to store data of two bytes every 15 minutes along 41 days as a maximum. After the setting up to the system by the computer, it can operate in stand alone way for up 41 days in the working place without the lose of any data. If the memory is full the next data will be written in the first locations of the memory. The memory is divided in pages corresponding every one of this to a different day of the acquisition. The counting time for every acquisition can be programmed by the user from 15 minutes to 65535 minutes but it is recommended to use a small time not to reach the limit of 65535 counts in every acquisition period. We can take information of the system without affecting the acquisition process in the field by using a lap top computer, then the information can be stored in a file. There is a program in the computer that can show the information in a table of values or in a bar graph. (Author)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-12-01

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

  1. Radon measurement studies in Kazakhstan

    International Nuclear Information System (INIS)

    Sevost'yanov, V.N.

    2003-01-01

    Today, one has to admit that despite the important role and certain achievements in providing the radiation control in Kazakhstan, radon measurements still present some problems related to clear definition of physical quantities applied, correct use of methods, and application of adequate measuring devices to meet requirements of regulatory documents currently in effect, such as NRB-99. The paper provides some data on radon measurements, describes the problem status in Kazakhstan and proposes ways to solve it. (author)

  2. The design and realization of calibration apparatus for measuring the concentration of radon in three models

    Energy Technology Data Exchange (ETDEWEB)

    Huiping, Guo [The Second Artillery Engineering College, Xi' an (China)

    2007-06-15

    For satisfying calibration request of radon measure in the laboratory, the calibration apparatus for radon activity measure is designed and realized. The calibration apparatus can auto-control and auto-measure in three models. sequent mode, pulse mode and constant mode. The stability and reliability of the calibration apparatus was tested under the three models. The experimental result shows that the apparatus can provides an adjustable and steady radon activity concentration environment for the research of radon and its progeny and for the calibration of its measure. (authors)

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

    International Nuclear Information System (INIS)

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

    1987-01-01

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

  4. Radon measurements in Greece

    International Nuclear Information System (INIS)

    Georgiou, E.; Ntalles, K.; Molfetas, M.; Athanassiadis, A.; Proukakis, C.

    1988-01-01

    Studies of radon concentration in greek spas, in a cave, in constituents of the greek cement, in building materials in Greece and in greek mines have been published. Some preliminary studies of radon concentration in greek dwellings have been published. In order to get an idea of the problem in Greece we decided to carry out a national survey. Two different sites were selected: Athens, where domicile about 40% of the greek population and Domatia, a small village in northern Greece 600Km from Athens, located in an area known to have soil with increased uranium concentrations

  5. Radon measurements in underground and ground constructions in Tashkent city

    International Nuclear Information System (INIS)

    Akimov, V.A.; Yafasov, A.Y.; Vasidov, A.; En, Z.; Tillaev, T.; Tsipin, V.Z.

    2002-01-01

    More than half of the dose of the natural radioactivity received by population is related to radon and its progeny. Investigations of scientists all over the world have shown that excessive radon and its progeny exposure dose is associated with a risk of lung cancer. Short-lived radon daughters (Po-218 and Po-214) are considered to be of the most dangers. At a relaxation process resulting from an earthquake, the radon gas can release from the accumulators and get indoors, that enhances greatly the radon level there. According to seismologists data, as a result of the strong Tashkent earthquake in 1966, extensive breaks and faults have been formed along the city and its neighborhoods. The aim of our work was evaluation of radon concentration level and its variation in Tashkent subway stations and related underground offices and also in apartments of multi story buildings and detached houses. The measurements were conducted by two different techniques-with ionization chamber radiometer 'Alpha GUARD' and with solid state nuclear track detectors. The Alpha GUARD radiometer operates either in the mode of passive sampling, or by pumping air through the ionization camera being of 0.6 l in volume. The radiometer is capable of measuring a volumetric activity of radon-222 in air (Bq/m3), and it is equipped with the devices that measure some environmental parameters such as temperature, relative humidity and air pressure. The range of V A of 222 Rn in air the device is able to measure is 10 to 2x10 6 Bq/m 3 , sensitivity is 1 pulse/min for 20 Bq/m 3 , and its self-background is less than 1 Bq/m 3 . The radon measurements in Tashkent subway stations and underground offices have shown that daily mean radon values were in the range of 14-65 Bq/m 3 , except for the Pushkin Station, where the daily mean V A was 137 Bq/m3. Such a high radon level is connected with availability near the station of one of the numerous faults and fractures of the terrestrial crust responsible for the

  6. Radon gas measurement in Corum

    International Nuclear Information System (INIS)

    Uzbey, S.; Celebi, N.

    2009-01-01

    The existence of the natural radioactive sources in earth's crust which has long half-life and the degradation products of these in the environmental medium such as earth, rocks, foods, water, air, forms the basis of radiation which people are exposed to. Radon is the unique radioactive gas in the nature and it is made up of radium which is the result of uranium degradation. It is necessary to determine the radon concentration because of the difference in the concentration of uranium existence in different places. TAEK (Turkish Atomic Energy Authority) allows 400 Bq/m 3 of radon concentration at houses, 1000 Bq/m 3 at offices per year. In this attempt, government buildings, houses and offices were determined as the sampling places in Corum city center and towns to represent Corum. While disposing the radon measuring detectors, places which are close to the ground level were preferred. 74 radon detectors were left in those places for 60 days and in the end the detectors were collected while discontinuing the connection of environment and they were assessed. According to the results, the average radon gas concentration in 14 government buildings is 71,71 Bq/m 3 , in 15 offices 32,26 Bq/m 3 and at houses 42,34 Bq/m 3 .

  7. Radon Measurements in Egypt using passive etched track detectors. A Review

    Energy Technology Data Exchange (ETDEWEB)

    Gomaa, M A [National Network of Radiation Physics. Atomic Energy Authority (Egypt); Hussein, A S [Radiation Protection Department, Nuclear Power Plants Authority, (Egypt); El-Arabi, A M [Physics Department, Faculty of Science, South Valley University, Qena, (Egypt)

    2005-04-01

    Radon and its progeny may cause serious radiation harm to human health such as lung cancer and other types. Radon measurements based on alpha particles etched track detectors (LR-115, CR-39) are very attractive for assessment of radon exposure. This is due to their high sensitivity, low cost, easy to handle and retain a permanent record of data. Also these detectors can incorporate the effects of seasonal and diurnal fluctuation of radon activity concentrations due to physical, geological and meteorological factors. The present review is based mainly on the topic of passive etched track detectors for the measurements of radon in Egypt in the recent years. Published papers includes the measurements of radon in dwellings, working places, Cairo Metro stations, ancient Pharaonic places and uranium exploration galleries as well as assessment of radon in drinking water.

  8. Radon Measurements in Egypt using passive etched track detectors. A Review

    International Nuclear Information System (INIS)

    Gomaa, M.A.; Hussein, A.S.; El-Arabi, A.M.

    2005-01-01

    Radon and its progeny may cause serious radiation harm to human health such as lung cancer and other types. Radon measurements based on alpha particles etched track detectors (LR-115, CR-39) are very attractive for assessment of radon exposure. This is due to their high sensitivity, low cost, easy to handle and retain a permanent record of data. Also these detectors can incorporate the effects of seasonal and diurnal fluctuation of radon activity concentrations due to physical, geological and meteorological factors. The present review is based mainly on the topic of passive etched track detectors for the measurements of radon in Egypt in the recent years. Published papers includes the measurements of radon in dwellings, working places, Cairo Metro stations, ancient Pharaonic places and uranium exploration galleries as well as assessment of radon in drinking water

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

    International Nuclear Information System (INIS)

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

    2015-01-01

    Could jewellery made from uranium glass beads pose an increased risk to skin cancer? The literature Eatough (Alpha-particle dosimetry for the basal layer of the skin and the radon progeny 218 Po and 214 Po. Phys. Med. Biol. 1997;42:1899-1911.) suggests that the alphas from the short-lived radon daughters, 218 Po and 214 Po, may reach the basal layer of the epidermis, which is believed to be important in the induction of skin cancers. The deposition of the alphas from the 218 Po and 214 Po daughters was investigated using PADC detector material. The expectation would be that no alpha particles would penetrate through the dead skin layer, assuming the average of 70 microns used in radiation protection, but the skin around the collar bone could potentially be thinner than the assumed average. It should be noticed that by inserting a slice of pig skin in between the necklace and the PADC, no great excess of alpha tracks were seen after 1 week of exposure in the freezer. There was, however, a clear signal through the pig skin from beta particles, confirming the potential of a uranium bead necklace posing a health risk. (authors)

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

    International Nuclear Information System (INIS)

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

    1998-01-01

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

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

    International Nuclear Information System (INIS)

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

    2013-01-01

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

  12. Measurement of concentration and size distribution of radon decay products in homes using air cleaners

    International Nuclear Information System (INIS)

    Montassier, N.; Hopke, P.K.; Shi, Y.; McCallum, B.

    1992-01-01

    By removing particles, air cleaners can also eliminate radon decay products. However, by removing the particles, the open-quotes unattachedclose quotes fraction of the radon progeny is increased leading to a higher dose per unit exposure. Thus, both the concentration and size distributions of the radon decay products are needed to evaluate air cleaners. Three types of room air cleaners, NO-RAD Radon Removal System, Electronic Air Cleaner and PUREFLOW Air Treatment System were tested in a single family home in Arnprior, Ontario (Canada). Semi-continuous measurements of radon gas concentration and radon decay product activity weighted size distribution were performed in the kitchen/dining room under real living conditions. The effects of air cleaners on both the concentration and size distribution of the radon decay products were measured, and their impact on the dose of radiation given to the lung tissue were examined

  13. Quality assurance for radon measurements in Germany

    International Nuclear Information System (INIS)

    Beck, T.R.; Buchroeder, H.; Foerster, E.; Schmidt, V.

    2005-01-01

    Full text: Radiation protection regarding work activities at workplaces with naturally occurring radiation has been regulated in the German Radiation Protection Ordinance. Regulations refer only to workplaces where the presence of natural radiation leads to a significant increase in the exposure of workers. These workplaces were identified in the following working areas with enhanced exposures to radon-222: underground mines, including visitor mines and show caves; radon-spas and galleries; water supply and distribution industries. Presently, regulations are being initiated by the German government to limit the exposures to radon in homes. For radon measurements at workplaces passive radon devices for individual monitoring as well as active measuring systems for workplace monitoring can be used. However, passive radon devices are preferred for radon measurements in homes because of low costs and availability in large quantities. To assure the quality of radon measurements the German Federal Office for Radiation Protection (BfS) has established annual interlaboratory comparisons for passive radon devices. The comparisons are carried out in the BfS radon calibration laboratory accredited by the German Calibration Service. Passive radon devices which use solid state track detectors, electrets or activated charcoal can be submitted. Approved radon services which offer radon measurements to determine radon exposure in homes and at workplaces have to pass the comparisons successfully. (author)

  14. Comparison of different methods for thoron progeny measurement

    International Nuclear Information System (INIS)

    Bi Lei; Zhu Li; Shang Bing; Cui Hongxing; Zhang Qingzhao

    2009-01-01

    Four popular methods for thoron progeny measurement were discussed, including the aspects of detector,principle, precondition, calculation advantages and disadvantages. Comparison experiments were made in mine and houses with high background in Yunnan Province. Since indoor thoron progeny changes with time obviously and with no rule, α track method is recommended in the area of radiation protection for environmental detection and assessment. (authors)

  15. Why measure radon decay products?

    International Nuclear Information System (INIS)

    Rolle, R.; Lettner, H.

    1997-01-01

    Combined development in spectrometry, instrumentation and ventilation modelling with its dependence on short- and long-term weather fluctuations renders possible a new, economical metrology for radon decay products. Short-term measurements can, with few restrictions, be converted to annual exposures of an accuracy superior to that from conventional medium-term Rn gas measurements. (orig.) [de

  16. Radon-222 measurements at Chester

    International Nuclear Information System (INIS)

    Fisenne, I.M.

    1982-01-01

    The Environmental Measurements Laboratory has compiled a five year record of continuous hourly radon-222 measurements at Chester, New Jersey. The data for the 1977-1978, 1978-1979, 1979-1980, and 1980-1981 have been reported previously

  17. Radon Measurements In Preschool And School Facilities In The Municipality Of Bank's Kapur

    International Nuclear Information System (INIS)

    Kadic, I.; Deljkic, D.; Ilic, Z.

    2015-01-01

    Radon is a radioactive noble gas, chemically inert and motile at room temperature. It is a colorless and odorless gas, but the characteristic of radioactivity enables us to detect it and measure it by two methods - the passive and the active one. The results of a research on concentration of radon activity in the air of preschool's and school's indoors in the area of the municipality of Bosanska Krupa in 2013 is shown in this work. To determine radon concentration, passive measuring method was used, canisters of radon with active carbon, with correction for the air humidity. The active carbon is placed into a canister that is opened during measurements and placed on the wanted location. Radon from the air arrives into the canister and is adsorbed on the active carbon which has high affinity towards few gases and steams, including 222Rn. Adsorbed radon in granules of active carbon is decomposed to short-living progeny: 218Po, 214Pb, 214Bi, 214Po and 210Pb. Radon's progeny 214Pb and 214Bi emit gamma-rays, it permits determination of the radon concentration via gamma-spectrometry through mentioned transitions, because three hours later the equilibrium between radon and its progeny in the carbon has already been established. The measurements have been conducted on high-resolution gamma spectrometer Ortec with 30 percent relative efficiency, integrated electronic system (Ortec) and GAMMA VISION (Ortec) software for spectra processing, analysis and evaluation of the results of measurements. The purpose of this work was to detect the levels of radon, targeting the protection of the youngest population in case of high radon concentrations in residential areas. (author).

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

    International Nuclear Information System (INIS)

    Marsh, J.W.; Birchall, A.

    1999-01-01

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

  19. 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

  20. Measured radon inside housings the Republic Argentina

    International Nuclear Information System (INIS)

    Canoba, A.; Arnaud, M.; Lopez, F.; Oliveira, A.A.

    1998-01-01

    They have been measured the radon concentration in houses in different city's in Argentina Republic. For they were used it as method mensuration detectors appearances nuclear detecting electrets and detectors based on the adsorption radon in activated carbon

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

    International Nuclear Information System (INIS)

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

    2003-01-01

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

  2. 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

  3. 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

  4. Instrumentation for radon measurement and diagnosis

    International Nuclear Information System (INIS)

    Whyte, N.; Ellacott, K.; Brabant, L.

    1990-01-01

    Knowledge of existing protocols and guidelines, coupled with equipment acumen can make for a successful endeavor in the radon field. But where do you collect a users perspective on radon equipment? Obtaining a first hand understanding of how radon detection equipment may be applied can be a lengthy and expensive process. In this paper first principals of progeny collection, and counting, are covered. Use of Thomson and Nielsen equipment to screen, and diagnose radon will e presented. Equipment performance in a wide variety of field applications and in calibration chambers will be brought to light. The distinctive nature and versatility of the equipment will e outlined with applications information, system performance, and unique configurations

  5. Application of underwater radon measurements in geology

    Energy Technology Data Exchange (ETDEWEB)

    Varhegyi, A.; Baranyi, I.; Gerzson, I. (Mecsek Ore Mining Enterprise, Pecs (Hungary)); Somogyi, G.; Hakl, J.; Hunyadi, I. (Magyar Tudomanyos Akademia, Debrecen (Hungary). Atommag Kutato Intezete)

    1988-01-01

    Based on the observed phenomenon of geogas migration in microbubble form from deeper regions, the authors have developed a new model for the vertical transport of radon released from deeper sources. The physical properties of the rock relating to the upflow of microbubbles below the groundwater level are considered and the radon transport parameter of rocks is introduced. The vertical distribution of radon concentration in the case of a multi-layered geological model is given and the penetration depth of underwater radon measurements is examined. Aspects of underwater radon detection by the nuclear track detector technique are analyzed. The radon transport model gives a new theoretical basis for several applications of radon measurements in geology. The advantages of underwater radon detection have already been proved in uranium exploration. Further geological applications are proposed in earthquake prediction, in volcanology, in the survey of active faults and thermal waters. (author).

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

    International Nuclear Information System (INIS)

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

    2010-01-01

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

  7. Measurement of the radon concentration in an underground public facility and dose assessment. Fukuoka Tenjin Shopping Center

    International Nuclear Information System (INIS)

    Narazaki, Yukinori; Tokonami, Shinji; Sanada, Tetsuya; Kanno, Nobuyuki; Yamada, Yuji

    2000-01-01

    Radon concentrations were measured with a passive radon detector from April 1998 through June 1999 in the Fukuoka Tenjin Underground Shopping Center to assess the dose affecting workers because of radon progeny inhalation. The radon concentration during the period was distributed from a range of 1.9 to 13.6 Bq/m 3 . The arithmetic average concentration was estimated to be 6.9±2.4 Bq/ 3 . The radon level was lower than that in dwellings in Japan and other countries. No spatial distribution of radon concentration was found in that area. From continuous measurement, the radon concentration was found to be high from midnight to noon and low in the afternoon. Little difference was noted between the daily average radon concentration and that during working hours. There was no seasonal variation. The equilibrium factor of 0.21±0.10 was obtained during working hours. The activity-weighted size distribution of radon progeny was evaluated by using the number distribution of ambient aerosols and the classical attachment theory. Consequently, the activity median diameter was 150 nm. The unattached fraction of radon progeny was estimated to be 0.025 with an empirical equation. The annual effective dose of workers at the Tenjin center was calculated with the dose conversion factor from the UNSCEAR 1993 report and estimated to be 0.024 mSv/y. (author)

  8. 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)

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

    Energy Technology Data Exchange (ETDEWEB)

    Hopke, P.K.

    1992-07-01

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

  10. Ethanol as radon storage: applications for measurement

    International Nuclear Information System (INIS)

    Winter, I.; Philipsborn, H. von

    1997-01-01

    Ethanol as Radon Storage: Applications for Measurement Ethanol has a solubility for radon of 6 Bq/l per kBq/m 3 air, 24 times higher than water. On filtration of ethanol, radon decay products are completely adsorbed on glass fiber filters, as previously reported for water. Hence: 1. A new simple method for measuring radon in soil air, without expensive equipment. 2. The production of mailable radon calibration sources ('radonol') with 50-100 kBq/l in PET-bottles with 3.8 days half-life, using uraniferous rocks as primary source. (orig.) [de

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

    Energy Technology Data Exchange (ETDEWEB)

    Hopke, P.K.

    1992-07-01

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

  12. 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

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

    International Nuclear Information System (INIS)

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

    2006-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-07-01

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

  15. 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)

  16. Integral measurement system for radon

    International Nuclear Information System (INIS)

    Garcia H, J.M.; Pena E, R.

    1996-01-01

    The Integral measurement system for Radon is an equipment to detect, counting and storage data of alpha particles produced by Radon 222 which is emanated through the terrestrial peel surface. This equipment was designed in the Special Designs Department of the National Institute of Nuclear Research. It supplies information about the behavior at long time (41 days) on each type of alpha radiation that is present into the environment as well as into the terrestrial peel. The program is formed by an User program, where it is possible to determine the operation parameters of a portable probe that contains, a semiconductor detector, a microprocessor as a control central unit, a real time clock and calendar to determine the occurred events chronology, a non-volatile memory device for storage the acquired data and an interface to establish the serial communications with other personal computers. (Author)

  17. 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.)

  18. The field measurements of the activity-weighted size distributions of radon decay products

    International Nuclear Information System (INIS)

    Wasiolek, P.; Montassier, N.; Hopke, P.K.

    1991-01-01

    Because of the importance of particle size in the calculations of dose deposited in the respiratory tract by radon progeny, the determination of the size distribution of radon decay products in indoor air had increased in interest in recent years. A system for the measurement of the activity-weighted size distribution of radon decay products at environmental levels has been developed. The system (ASC-GSA) utilizes a combination of six multiple wire screens (Graded Screen Array) sampler detector units operated in parallel. The cut off points of the samplers and the data deconvolution procedure allow to obtain the activity fractions of radon progeny in the size range 0.5-500 mn. The computer control of sampling, alpha counting and data storage permits the operation of the system on the semi-continuous basis. The primary application of the ASC-GSA system has been to collect data of activity-weighted size distributions of radon progeny in real house environments. The results of field measurements in several houses with elevated radon levels are presented

  19. Improved thomas formula for radon measurement

    International Nuclear Information System (INIS)

    Ji Changsong

    1991-06-01

    The FT 648 type portable absolute radon meter has been developed and the designing principle of this instrument is introduced. The absolute radon meter differs from relative radon meter. By using structure parameters, operating parameters and readout of this instrument, the radon content of measured gas is obtained directly without calibration in advance. Normally, the calibration is done by a standard radioactive gaseous source of which the radon concentration is known. The systematic error is removed by adding filter-efficiency Σ, α self-absorption correction β, energy spectrum correction S, geometric factor Ω of probe and gravity dropping correction factor G to the Thomas formula for radon measurement of two-filter method. The atmosphere radon content, which is given in hour-average, in Beijing area was measured by FT 648 type absolute radon meter. The measurement lasted continuously for several days and nights and a 'saddle shape' of radon content-time curve was observed. The day's average radon content was 8.5 Bq·m -3

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

    International Nuclear Information System (INIS)

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

    1982-09-01

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

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

    International Nuclear Information System (INIS)

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

    2006-01-01

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

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

    International Nuclear Information System (INIS)

    Khan, Atika; Phillips, C.R.

    1988-01-01

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

  3. Methods of radon measurement and devices

    International Nuclear Information System (INIS)

    Miles, J.

    2004-01-01

    The following topics and instrumentation are discussed: The quantity to be measured; Active measurement methods (scintillation cells, ionisation chambers, electrostatic collection of decay products); Passive measurement methods (charcoal detectors; electret ion chambers; etched track detectors); and Detector considerations for large-scale surveys ('always on' or 'switchable' detectors?; response to radon-220; avoidance of electrostatic effects; quality assurance for passive radon detectors; quality control within the laboratory; external quality assurance; detectors need to be easily deliverable). It is concluded that the ideal detector for large scale surveys of radon in houses is a small, closed detector in a conducting holder which excludes radon-220, supported by rigorous quality assurance procedures. (P.A.)

  4. Result of the intercomparison exercise on radon measuring instruments and radon detectors 'bev- radon ring 2005'

    International Nuclear Information System (INIS)

    Baumgartner, A.; Maringer, F.J.; Michai, P.; Kreuziger, M.

    2006-01-01

    In spring 2005 the Federal Office of Metrology and Surveying (B.E.V.) invited all in Austria working radon measuring institutes to an intercomparison exercise at the radon calibration laboratory in the Arsenal. The aim of this intercomparison was on the one hand an objective inquiry and documentation of the current metrological potential on the section of radon measurement in Austria - both quantitative and qualitative- and on the other hand an initiative for the participating laboratories to optimize and improve their applied calibration-, measurement and analyse technique. Ten contacted Austrian radon laboratories were prepared to participate on the radon intercomparison exercise. The intercomparison exercise was carried out from 14. till 29. June at the radon calibration laboratory in the Arsenal of the B.E.V.. As radon emanation source a five stepped arranged, at the Arsenal built radon source was used. The source ( A.D.O.T.T.O. 1 is filled with a certified Ra- 226-standard solution of the Czech Metrological Institute (C.M.I.), Prag. A simple statistic based model was used for the evaluation and assessment of the results from the participants, which consider the statistic nature of the radioactive decay combined uncertainty. Altogether 183 measuring instruments participated the intercomparison exercise. Two reference measuring instruments, 22 active and 159 passive measuring instruments. The active measuring instruments formed 6 types of instruments and as passive radon detectors were 7 different types used from the participants. The positioning of the radon measuring instruments and detectors in the radon calibration laboratory was executed in regard to statistic points of view. From the active measuring instruments 17 could qualify and from the passive methods six from eight participants were in compliance to the given criteria. Radon measurements, which could have financial and economics relating implications (e.g. architectural redevelopment or

  5. Radon in the indoor environment

    International Nuclear Information System (INIS)

    Vanmarcke, H.

    1998-01-01

    The objectives of R and D on radon in the indoor environment at SCK-CEN is to (1) to investigate the deposition of radon progeny in the human respiratory tract by means of direct measurements as a function of aerosol conditions; to assess the radon concentrations in buildings retrospectively with volume traps. Progress and main achievements in 1997 are reported on

  6. Radon in the indoor environment

    International Nuclear Information System (INIS)

    Vanmarcke, H.

    1998-01-01

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

  7. Operating instructions for LBL radon measurement facilities

    International Nuclear Information System (INIS)

    Ingersoll, J.G.

    1980-06-01

    This manual is intended for users of the radon-measuring facilities of the Radon Project of the Building Ventilation and Indoor Air Quality Program at Lawrence Berkeley Laboratory. The manual comprises three parts. Part 1 sets out the steps involved in collecting, transferring, and counting radon. Part 2 describes the calibration of the transfer system and of the Lucas cells in the counting system. Part 3 outlines the maintenance procedures for the facility

  8. 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

  9. Radon measurements in 130 schools

    International Nuclear Information System (INIS)

    Peake, R.T.; Schmidt, A.; MacWaters, J.T.; Chmelynski, H.

    1990-01-01

    During the winter of 1989, Rn screening measurements were made in 130 schools distributed across the United States. The primary purpose of the paper is to identify schools suitable for a year-long follow-up study, the results of which will be used to update EPA's guidance for Rn testing in schools. The 130 schools were selected nonrandomly using school characteristics and accessibility in areas where there were known or suspected Rn problems in homes. Levels found in this screening study may indicate the potential for Rn problems in US schools. Over half of the 130 schools tested had at least one radon measurement ≥4 pCi/L, and nearly 20% of the 3028 rooms measured ≥4 pCi/L. The number of rooms ≥4 pCi/L is often three rooms or less. However, schools with more than five rooms ≥4 pCi/L are common in some areas. The data include schools that could be typical of much of the US school population as well as schools which exhibit extreme radon problems, such as those tested in Nashville, TN and Spokane, WA

  10. 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

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

    International Nuclear Information System (INIS)

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

    2018-01-01

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

  12. Radon measurements in mines and dwellings

    International Nuclear Information System (INIS)

    Urban, M.

    1985-01-01

    Radon measurements using a time integrating passive radon dosemeter (MAKROFOL track etch detector) have been performed in Brazilian and German mines and dwellings. The present state of the measurement technique is summarized. The results are presented together with exposure calculations and dose estimations for occupational exposure in open pit and underground mines and for the general public in houses. (orig./HP) [de

  13. Indoor radon measurements in Athens, Greece

    International Nuclear Information System (INIS)

    Proukakis, C.; Molfetas, M.; Ntalles, K.; Georgiou, E.; Serefoglou, A.

    1987-01-01

    A pilot study was carried out in order to measure air concentrations of radon 222 and 220 isotopes in Athenian houses, as a first step of a national survey in Greece. In this paper the authors deal with radon concentration in air and water and will rely on measurements conducted in Greece. (author)

  14. 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

  15. Radon diagnostics and tracer gas measurements

    International Nuclear Information System (INIS)

    Jilek, K.; Brabec, M.

    2004-01-01

    An outline is presented of the tracer gas technique, which is used for continuous measurements of air ventilation rate (generally time-varying) and for simultaneous estimation of air ventilation rate and radon entry rate, and some of its limitations are discussed. The performance of this technique in the calculation of the air ventilation rate is demonstrated on real data from routine measurements. The potential for air ventilation rate estimation based on radon measurements only is discussed. A practical application is described of the tracer gas technique to a simultaneous estimation of the air ventilation rate and radon entry rate in a real house where the effectiveness of radon remedy was tested. The following main advantages of the CO tracer gas techniques are stressed: (i) The averaging method continuous determination of the ventilation rate with good accuracy (≤ 20 %). (ii) The newly presented and verified method based on simultaneous measurements of radon concentration and CO gas concentration enables separate continuous measurements of the radon entry rate and ventilation rate. The results of comparative measurements performed with the aim to estimate the inaccuracy in determination of radon entry rate showed acceptable and good agreement up to approximately 10 %. The results of comparative measurements performed with the aim to estimate the mutual commensuration of the method to the determination of the ventilation rate confirmed the expected unreliability the two parametric non-linear regression method, which is the most frequently used method in radon diagnostic in the Czech Republic

  16. Measurement of unattached aerosols of {sup 222} Rn progeny by means of an electrostatic deposition method; Medicion de la fraccion no unida a aerosoles de la progenie de {sup 222} Rn mediante un metodo de deposicion electrostatica

    Energy Technology Data Exchange (ETDEWEB)

    Canoba, Analia C; Lopez, Fabio O [Autoridad Regulatoria Nuclear, Buenos Aires (Argentina)

    2001-07-01

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

  17. Comparison of methods and instruments for 222Rn/220Rn progeny measurement

    International Nuclear Information System (INIS)

    Liu Yanyang; Shang Bing; Wu Yunyun; Zhou Qingzhi

    2012-01-01

    In this paper, comparisons were made among three methods of measurement (grab measurement, continuous measurement and integrating measurement) and also measurement of different instruments for a radon/thoron mixed chamber. Taking the optimized five-segment method as a comparison criterion, for the equilibrium-equivalent concentration of 222 Rn, measured results of Balm and 24 h integrating detectors are 31% and 29% higher than the criterion, the results of Wl x, however, is 20% lower; and for 220 Rn progeny, the results of Fiji-142, Kf-602D, BWLM and 24 h integrating detector are 86%, 18%, 28% and 36% higher than the criterion respectively, except that of WLx, which is 5% lower. For the differences shown, further research is needed. (authors)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-05-15

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

  19. Radon measurements at the FEMP

    International Nuclear Information System (INIS)

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

    1993-08-01

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

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

    International Nuclear Information System (INIS)

    Nikezic, D.; Yu, K.N.

    2010-01-01

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

  1. Study of radon dispersion in typical dwelling using CFD modeling combined with passive-active measurements

    Science.gov (United States)

    Rabi, R.; Oufni, L.

    2017-10-01

    Inhalation of radon (222Rn) and its decay products are a major source of natural radiation exposure. 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. Indoor air conditions and ventilation systems strongly influence the indoor radon concentration. This study focuses on investigating both numerically and experimentally the influence of environmental conditions on the indoor radon concentration and spatial distribution. The numerical results showed that ventilation rate, temperature and humidity have significant impacts on both radon content and distribution. The variations of radon concentration with the ventilation, temperature and relative humidity are discussed. The measurement results show the diurnal variations of the indoor radon concentration are found to exhibit a positive correlation with relative humidity and negatively correlate with the air temperature. The analytic solution is used to validate the numeric results. The comparison amongst analytical, numerical and measurement results shows close agreement.

  2. 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)

  3. Absolute measurement of environmental radon content

    International Nuclear Information System (INIS)

    Ji Changsong

    1987-01-01

    A transportable meter for environmental radon measurement with a 40 liter decay chamber is designed on the principle of Thomas two-filter radon content absolute measurement. The sensitivity is 0.37 Bq·m -3 with 95% confidence level. This paper describes the experimental method of measuremment and it's intrinsic uncertainty. The typical intrinsic uncertainty (for n x 3.7 Bq·m -3 radon concentration) is <10%. The parameter of exit filter effeciency is introduced into the formula, and the verification is done for the case when the diameter of the exit filter is much less than the inlet one

  4. 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

  5. Radon remedial measures in cold climate

    International Nuclear Information System (INIS)

    Birovljev, A.

    2004-01-01

    A view is taken that mitigation of an indoor radon problem is often more complex than usually assumed, and that additional factors should be considered to avoid situations in which after mitigation the radon problem may be solved, but other problems have been created. Emphasis is put on how the choice and design of radon remedial measures are influenced not only by effectiveness in reducing radon levels indoors, but also by climatic factors, energy-saving aspects, as well as economic and psycho-social factors. Climatic conditions give rise to several concerns when attempting to mitigate a radon problem in areas with large seasonal temperature variations. Problems with humidity, energy consumption and durability of sealing materials are probably the most prominent issues. Commonly used radon remedial measures and their effectiveness in Norway is reviewed. Discussion is focused on principles and technical solutions which produce good results, and those which don't perform so well in cold Norwegian climate. Innovative technical solutions which successfully resolve some of the main conflicting issues are discussed. Results of some preliminary tests showing performance of such solutions in reduction of radon levels are presented. Other aspects of mitigation systems, such as need and cost of maintenance, longevity, noise levels, 'additional benefits', etc., are briefly mentioned. Homeowners' perceptions and willingness to implement various mitigation solutions are briefly reviewed. Based on discussion, several guiding principles which may be adopted in search for optimal solutions are suggested. (author)

  6. Measurements of radon levels inside Mexican caves

    International Nuclear Information System (INIS)

    Borau, J.; Gonzalez, A.; Espinosa, G.; Golzarri, J.I.

    1993-01-01

    Living animal species on earth have been exposed to environmental radon from the very beginning of time. The effects of radiation, combined with other natural parameters such as temperature, humidity, salt contents, etc., have most likely influenced the evaluation of different species. Thus, it is important to know and to evaluate the radon levels, among other radioactive elements present in enclosed environments such as caves, especially since those caves were also the dwellings and refuge of the predecessor of man. In this work we present radon level measurements inside some caves with vestiges of ancient inhabitats and some recently discovered natural caves, using Nuclear Track Detectors. (author)

  7. Radon measurements in Rio de Janeiro

    International Nuclear Information System (INIS)

    Magalhaes, M.H.; Amaral, E.C.S.; Sachett, I.

    2002-01-01

    Few data are available on the dynamic of radon in the air for tropical climate conditions. The strong influence of the climatological characteristics on the transport of gases and particulates in air makes not adequate the use of data obtained at regions with different climate. Outdoor and indoor measurements of radon equilibrium equivalent concentrations (EEC) have been done for one-year period in Rio de Janeiro. Continuous measurements were performed using a radon monitor with an alpha spectrometry detector. Pluviometric index, temperature and humidity were registered. The paper presents the long term behaviour of outdoor radon equilibrium equivalent concentration results, their correlation with temperature and the influence of the pluviometric index. Maximum values were obtained during winter and minimum in summer, strongly influenced by the rain. A strong inverse correlation with temperature was found. (author)

  8. Indoor radon measurements in dwellings of Mizoram

    International Nuclear Information System (INIS)

    Lalramengzami, R.; Laldawngliana, C.; Sinha, D.; Ghosh, S.; Dwivedi, K.K.

    1995-01-01

    The concentration of indoor radon has been measured in some dwellings of Mizoram state by employing time integrated method using solid state nuclear track detector. This state is located in the north eastern region of India which has been identified as a high background area. The indoor radon levels determined in this work are compared with data obtained from other regions of India and the Environmental Protection Agency (EPA) prescribed safe limit. (author). 7 refs., 2 figs

  9. Radon measurement in Malaysia water samples

    International Nuclear Information System (INIS)

    Ibrahim, A.B.; Rosli Mahat; Yusof Md Amin

    1995-01-01

    This paper reported the results of the measurement of radon in local water. The water samples collected were rainwater, river water, seawater, well water or ground water at area of State of Selangor and Kuala Lumpur. The samples were collected in scintillation cell ZnS(Ag) through Radon Degassing Unit RDU 200. Alpha activity was counted with scintillation counters RD 200 at energy 5.5 MeV. (author)

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

    Science.gov (United States)

    Sharma, Sumit; Kumar, Ajay; Mehra, Rohit

    2018-05-16

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

  11. Measurement of radon concentration in water using the portable radon survey meter.

    Science.gov (United States)

    Yokoyama, S; Mori, N; Shimo, M; Fukushi, M; Ohnuma, S

    2011-07-01

    A measurement method for measuring radon in water using the portable radon survey meter (RnSM) was developed. The container with propeller was used to stir the water samples and release radon from the water into the air in a sample box of the RnSM. In this method, the measurement of error would be water was >20 Bq l(-1).

  12. Radon measurement in the spa of Bizovac

    International Nuclear Information System (INIS)

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

    1996-01-01

    The spa of Bizovac is located 20 km on the west of Osijek in east Croatia. Radon concentrations in the air and water of the Bizovac spa were measured by the Radhome silicon detector and the average values were obtained as 70 Bq/m 3 in the indoor pool, 40 Bq/m 3 in the hotel room and 135 Bq/m 3 in the closed therapeutic bathroom. A special experiment was performed in a closed therapeutic bathroom by three bathtubes filled up with geothermal water as well as normal (potable) one from water-supply. Using measured radon concentrations in air by Radhome detector under the mentioned conditions in the closed bathroom, radon concentrations were assessed for the geothermal water as 25.3 Bq/m 3 and 2.7 Bq/m 3 for potable water. Radon in potable water, measured by the sampling glass ampoule and scintillation cell, had the concentration of 3.5 Bq/m 3 . The radon transfer factor from water to air in the indoor pool and therapeutic bathroom was 10 and 40 times higher than for normal dwelling factor (10 -4 ), respectively. The effective dose equivalent of inhaled radon for permanent personnel under the worst conditions in the spa (closed therapeutic bathroom) was 5.4 mSv/y, but visitors spending two weeks in the Bizovac spa could receive the dose of 77 μSv. (author)

  13. Indoor radon level measurements in Iran using AEOI passive dosimeters

    International Nuclear Information System (INIS)

    Sohrabi, M.; Solaymanian, A.R.

    1988-01-01

    A passive radon diffusion dosimeter was developed at the RPD of AEOI for nationwide indoor radon level measurements. Several parameters of the dosimeter were studied. Radon levels were determined in about 250 houses in Ramsar (a high natural radiation area), Tehran, Babolsar and Gonabad. In this paper, the results of some dosimeter parameters as well as radon levels in indoor air are reported

  14. Regressionanalysis of radon measurements; Regressionsanalysen von Radonmessungen

    Energy Technology Data Exchange (ETDEWEB)

    Buermeyer, J.; Neugebauer, T.; Hingmann, H.; Grimm, V.; Breckow, J. [Technische Hochschule Mittelhessen (THM), Giessen (Germany). Inst. fuer Medizinische Physik und Strahlenschutz (IMPS); Gundlach, M. [Technische Hochschule Mittelhessen (THM), Giessen (Germany). Fachbereich fuer Mathematik, Naturwissenschaften und Informatik

    2016-07-01

    In the course of the renewal of the Radiation Protection Guidelines for Germany, radon becomes a more prominent concern. Thus, it is important to gain more information on the temporal behaviour of radon and its measureable parameters. This work focuses on the determination on possible influencing factors using regression-analysis methods. So far the radon concentration has been analysed and it was revealed, that the most important impact comes from the gradient of the temperature and pressure as the difference of the values in and outside the building. The carbon dioxide, which was logged as an indicator for the influences of the inhabitant does not show the high influence on the Radon levels as expected.

  15. 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}.

  16. Radon measurement works in Dhaka city and central part of Bangladesh

    International Nuclear Information System (INIS)

    Talukder, S.R.; Hamid Khan, M.A.

    2011-01-01

    The major source of natural radiation that irradiates the human body is primarily due to inhalation of Radon and its short-lived progeny nuclides. It is well known that exposure of population to high concentration of Radon and its daughters for a long period leads to pathological effects like the respiratory functional changes and the occurrence of lung cancer. Solid State Nuclear Track Detectors (CR-39) are being used for detection and measurement works of radon and its progeny in Bangladesh. Dhaka the capital of Bangladesh and some areas of the central region of Bangladesh are chosen for the present study to measure the Radon concentration level of the country. Dhaka is one of the most populous cities in Bangladesh as well as in the world. High working levels (WL) were found in some locations of Dhaka city specially in the old part of the city where so many ancient building are established and in some villages of the central part of the country. The aim of the study is to prepare a Radon Map of Bangladesh and the results so far obtained have been presented in the paper. (author)

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

    International Nuclear Information System (INIS)

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

    2011-10-01

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

  18. A Radon Chamber without Radium Source for Detector Calibration and Radon Measurements

    International Nuclear Information System (INIS)

    Al-Azmi, D.; Karunakara, N.

    2008-01-01

    A radon chamber of volume 216 liters was designed and constructed for calibration of radon detectors and radon test measurements. The main feature of this chamber is that the active 226 Ra source, to generate the 222 Rn inside the chamber volume, is not required. Instead, 222 Rn from soil gas is utilized for this purpose. The supply of radon comes from the soil gas. Soil gas is drawn from the soil to fill the chamber with high radon concentration levels (∼ 80 kBq/m3). Desired radon concentration levels can be obtained by drawing the soil gas for different time durations and/or flow rate (author)

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

    Czech Academy of Sciences Publication Activity Database

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

    2010-01-01

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

  20. Express method and radon gas measurement detector

    International Nuclear Information System (INIS)

    Khajdarov, R.A.; Khajdarov, R.R.

    2004-01-01

    The purpose of this work was to improve the activated charcoal adsorption method. The detector consisted of an electronic unit (200 mm x 180 mm x 80 mm) and a scintillation cell (a tube 200 mm long, 60 mm diam.). The electronic unit contained a power supply, amplifier, discriminator, timer, counter and indicator. The scintillation cell contained a zinc sulfide scintillator, photomultiplier, preamplifier, high voltage power supply and a 200 ml chamber above the scintillator. This chamber was intended to situate activated carbon fibrous absorber and air compressor. In this method, air is drawn through a filter to remove radon decay products and then through the activated carbon cloth by using a compressor. Sampling takes between 5 and 15 minutes. After the sampling, the cloth is heated for 5-10 sec up to 200-250 deg C by electric current passing through the fiber. Radon gas evaporates from the cloth and the device detects scintillation pulses. Owing to a high radon preconcentration factor (by adsorption of radon on the activated carbon cloth from 50-150 L of air of and evaporation into the small volume of the chamber), the detection limit of the method is 2-4 Bq/m 3 . Since the distance between the filter, cloth and scintillator is over 80 mm, the detector only measures radiation from radon without interference from the radon decay products, remaining in the filter and cloth

  1. 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

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

    International Nuclear Information System (INIS)

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

    2014-10-01

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

  3. Protective measures during construction against radon exposure

    International Nuclear Information System (INIS)

    Horn, W.

    1990-01-01

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

  4. Passive and active measurements of radon-related parameters inside ancient Egyptian tombs in Luxor

    Energy Technology Data Exchange (ETDEWEB)

    Abo-Elmagd, M [Radiation Measurements Department, National Institute for Standard, Giza (Egypt); Metwally, S M [Faculty of Science, Department of Physics, Ain Shams University, Cairo (Egypt); El-Fiki, S A [Faculty of Science, Department of Physics, Ain Shams University, Cairo (Egypt); Eissa, H M [Radiation Measurements Department, National Institute for Standard, Giza (Egypt); Salama, E [Faculty of Science, Department of Physics, Ain Shams University, Cairo (Egypt)

    2007-01-15

    Radon and its related parameters were measured using passive (CR-39) and active (Alpha-Guard analyzer) techniques inside seven ancient Egyptian tombs of the Valley of the Kings in Luxor. The measurements were performed throughout the winter and summer seasons. The average radon concentration inside the tombs ranges from 96.9+/-10.8 to 415+/-43Bqm{sup -3} in winter and from 86.4+/-13.8 to 6102.8+/-573.6 in summer. Because of the variations of tombs dimensions and their ventilation systems, the equilibrium factor between radon and its progeny ranges from 0.228+/-0.02 to 0.95+/-0.05. The effective doses for the tomb workers, the tour guide and visitors were calculated. Active measurements show that radon exhalation rates range from 0.68+/-0.30 to 1.47+/-0.27Bqm{sup -2}h{sup -1} and from 0.60+/-0.03 to 1.42+/-0.05Bqm{sup -2}h{sup -1} for passive measurements. The real radium content was determined for all examined tombs by HPGe detector, while the effective radium content was obtained by Alpha-Guard and sealed cup techniques. Radon exhalation rates were correlated with the real radium content. A good correlation was found between active and passive measurements of radon exhalation rate.

  5. Passive and active measurements of radon-related parameters inside ancient Egyptian tombs in Luxor

    International Nuclear Information System (INIS)

    Abo-Elmagd, M.; Metwally, S.M.; El-Fiki, S.A.; Eissa, H.M.; Salama, E.

    2007-01-01

    Radon and its related parameters were measured using passive (CR-39) and active (Alpha-Guard analyzer) techniques inside seven ancient Egyptian tombs of the Valley of the Kings in Luxor. The measurements were performed throughout the winter and summer seasons. The average radon concentration inside the tombs ranges from 96.9+/-10.8 to 415+/-43Bqm -3 in winter and from 86.4+/-13.8 to 6102.8+/-573.6 in summer. Because of the variations of tombs dimensions and their ventilation systems, the equilibrium factor between radon and its progeny ranges from 0.228+/-0.02 to 0.95+/-0.05. The effective doses for the tomb workers, the tour guide and visitors were calculated. Active measurements show that radon exhalation rates range from 0.68+/-0.30 to 1.47+/-0.27Bqm -2 h -1 and from 0.60+/-0.03 to 1.42+/-0.05Bqm -2 h -1 for passive measurements. The real radium content was determined for all examined tombs by HPGe detector, while the effective radium content was obtained by Alpha-Guard and sealed cup techniques. Radon exhalation rates were correlated with the real radium content. A good correlation was found between active and passive measurements of radon exhalation rate

  6. Experience from using plastic film in radon measurement

    International Nuclear Information System (INIS)

    Joensson, G.

    1999-01-01

    Plastic film is a useful detector of radon gas. The method of detection of the gas is used for several decades to measure radon concentrations both indoors and in soil. Experiences from radon measurements in Sweden indoors, in soil and in water using the plastic film Kodak LR 115-II are discussed in this report. Some examples are given from various projects. One example is taken from a large scale mapping of indoor radon levels in houses, where the building material is the main source of radon. In another example the measurements from a large scale soil radon mapping are discussed. The use of the plastic film for measurements of radon levels in water is also discussed. All the investigations are made in order to give the authorities concerned information of the radon situation and to study the connection between high indoor radon levels and various types of cancers

  7. Seasonal Variability in European Radon Measurements

    Science.gov (United States)

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

    2009-04-01

    In temperate climates, domestic radon concentration levels are generally seasonally dependent, the level in the home reflecting the convolution of two time-dependent functions. These are the source soil-gas radon concentration itself, and the principal force driving radon into the building from the soil, namely the pressure-difference between interior and exterior environment. While the meteorological influence can be regarded as relatively uniform on a European scale, its variability being defined largely by the influence of North-Atlantic weather systems, soil-gas radon is generally more variable as it is essentially geologically dependent. Seasonal variability of domestic radon concentration can therefore be expected to exhibit geographical variability, as is indeed the case. To compensate for the variability of domestic radon levels when assessing the long term radon health risks, the results of individual short-term measurements are generally converted to equivalent mean annual levels by application of a Seasonal Correction Factor (SCF). This is a multiplying factor, typically derived from measurements of a large number of homes, applied to the measured short-term radon concentration to provide a meaningful annual mean concentration for dose-estimation purposes. Following concern as to the universal applicability of a single SCF set, detailed studies in both the UK and France have reported location-specific SCF sets for different regions of each country. Further results indicate that SCFs applicable to the UK differ significantly from those applicable elsewhere in Europe and North America in both amplitude and phase, supporting the thesis that seasonal variability in indoor radon concentration cannot realistically be compensated for by a single national or international SCF scheme. Published data characterising the seasonal variability of European national domestic radon concentrations, has been collated and analysed, with the objective of identifying

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

    International Nuclear Information System (INIS)

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

    1995-07-01

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

  9. Study on radon and thoron levels in different types of granitic work industries around Tumkur city

    International Nuclear Information System (INIS)

    Nagabhushan, S.R.; Ujjinappa; Srilatha; Sannappa, J.

    2013-01-01

    Radon, Thoron and its progeny monitoring has become a global phenomenon due to its health hazards on human being. The concentration of radon, thoron and their progeny levels have been measured in different types of Granite and brick work industries around Tumkur city by using LR-115 type II Solid State Nuclear Track Detectors (SSNTDs) have been used for the measurement of these gases. The higher concentration of radon, thoron and their progeny were observed in the dwellings near brick industries compared to Granite cutting and polishing industries. The inhalation dose due to Radon, Thoron and their progeny to the workers and public living near these industries have been estimated. (author)

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

    International Nuclear Information System (INIS)

    Gupta, Nitin; Kant, Krishan; Garg, Maneesha

    2013-01-01

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

  11. The measure and control system of mini-type radon room based on PC104

    International Nuclear Information System (INIS)

    Zhou Shumin; East China Inst. of Technology, Fuzhou; Tang Bin; Sun Yamin

    2005-01-01

    Radon room is one of the standard equipment which demarcates radon measure instrument. The paper discusses the dynamic method and mathematic model which keeps the radon consistence stability in radon room. The system is developed on PC104. The system can monitor the radon consistence and replenishment radon according the radon control parameter. (authors)

  12. Activity measurements of radon from construction materials

    Energy Technology Data Exchange (ETDEWEB)

    Fior, L.; Nicolosi Correa, J. [Federal University of Technology - Parana, UTFPR, Av. Sete de Setembro, 3165, Curitiba, PR 80230-901 (Brazil); Paschuk, S.A., E-mail: spaschuk@gmail.com [Federal University of Technology - Parana, UTFPR, Av. Sete de Setembro, 3165, Curitiba, PR 80230-901 (Brazil); Denyak, V.V. [Federal University of Technology - Parana, UTFPR, Av. Sete de Setembro, 3165, Curitiba, PR 80230-901 (Brazil); Schelin, H.R. [Federal University of Technology - Parana, UTFPR, Av. Sete de Setembro, 3165, Curitiba, PR 80230-901 (Brazil); Pele Pequeno Principe Research Institute, Av. Silva Jardim, 1632, Curitiba, PR 80250-200 (Brazil); Soreanu Pecequilo, B.R. [Institute of Nuclear and Energetic Researches, IPEN, Av. Prof. Lineu Prestes, 2242-/05508-000 Sao Paulo (Brazil); Kappke, J. [Federal University of Technology - Parana, UTFPR, Av. Sete de Setembro, 3165, Curitiba, PR 80230-901 (Brazil)

    2012-07-15

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

  13. Measurements of indoor radon concentration in Libyan cities

    International Nuclear Information System (INIS)

    Elarabiy, S. F.; Khalifa, M.; Misrati, N.; Chahboune, N.; Ahmed, M.

    2012-12-01

    Studies confirm that the risk of exposure to indor radon is attributable to lung cancer worldwide. The relationship between radon exposure and cancer is a linear one which necessitates for need for measurements of indoor radon concentration. This paper presents the results of measurements of indoor radon in several libya cities using CR-39 plastic. The results showed that the average radon concentration in the cities of Tripoli, Al-harcha and Alrajaban were 48.8 Bg/m 3 , 51.4 Bg/m 3 and 55.5 Bg/m 3 respectively. The average indoor radon concentration in Libya is low comparing with other studies. (Author)

  14. 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

  15. Passive and Active Measurements of Radon related parameters inside ancient Egyptian Tombs in Luxor

    International Nuclear Information System (INIS)

    Abo-Elmagd, M.; Eissa, H.M.; Metwally, S.M.; Fiki, S.A.; Salama, E.

    2005-01-01

    Radon concentration and its exhalation rate were measured using active (Alpha-Guard analyzer) and passive (CR-39) techniques inside seven ancient Egyptian tombs of the Kings valley in Luxor. The measurements were performed during the winter season of tourism (15/10/2003 up to 09/02/2004). The real radium content was determine for all examined tombs by HPGe detector, while the effective radium content was obtained by Alpha-Guard and sealed cup techniques. The average radon concentration inside the tombs based on the active technique ranges from 116 42 to 362 115 Bq m-3 and the exhalation rate ranges from 0.68 to 1.47 Bq m-2 h-1. For passive measurements, the average radon concentrations inside the tombs vary from 88 5 to 517 8 Bq m-3 while the exhalation rate ranges from 0.60 to 1.42 0.05 Bq m-2 h-1. Because of the variations of tombs dimensions and their ventilation systems, the equilibrium factor between radon and its progeny ranges from 0.10 0.04 to 0.99 0.14 based on Can and Bare measurement method. The effective dose rate inside the tombs varies from 0.11 0.04 to 4.28 0.68 Sv/h, based on UNSCEAR 2000 dose conversion factors for radon and its progeny. Radon exhalation rate was correlated with the real radium content. Moreover, a good correlation was found between active and passive measurements. So it may be useful to use passive technique in large scale instead of the active one

  16. Passive and Active Measurements of Radon related parameters inside ancient Egyptian Tombs in Luxor

    Energy Technology Data Exchange (ETDEWEB)

    Abo-Elmagd, M; Eissa, H M [National institute for standerd, radiation Measurements department, Giza (Egypt); Metwally, S M; Fiki, S A; Salama, E [Faculty of Science Department of physics, Ain Shams University, Cairo (Egypt)

    2005-04-01

    Radon concentration and its exhalation rate were measured using active (Alpha-Guard analyzer) and passive (CR-39) techniques inside seven ancient Egyptian tombs of the Kings valley in Luxor. The measurements were performed during the winter season of tourism (15/10/2003 up to 09/02/2004). The real radium content was determine for all examined tombs by HPGe detector, while the effective radium content was obtained by Alpha-Guard and sealed cup techniques. The average radon concentration inside the tombs based on the active technique ranges from 116 42 to 362 115 Bq m-3 and the exhalation rate ranges from 0.68 to 1.47 Bq m-2 h-1. For passive measurements, the average radon concentrations inside the tombs vary from 88 5 to 517 8 Bq m-3 while the exhalation rate ranges from 0.60 to 1.42 0.05 Bq m-2 h-1. Because of the variations of tombs dimensions and their ventilation systems, the equilibrium factor between radon and its progeny ranges from 0.10 0.04 to 0.99 0.14 based on Can and Bare measurement method. The effective dose rate inside the tombs varies from 0.11 0.04 to 4.28 0.68 Sv/h, based on UNSCEAR 2000 dose conversion factors for radon and its progeny. Radon exhalation rate was correlated with the real radium content. Moreover, a good correlation was found between active and passive measurements. So it may be useful to use passive technique in large scale instead of the active one.

  17. Radon measurements: the sources of uncertainties

    International Nuclear Information System (INIS)

    Zhukovsky, Michael; Onischenko, Alexandra; Bastrikov, Vladislav

    2008-01-01

    Full text: Radon measurements are quite complicated process and the correct estimation of uncertainties is very important. The sources of uncertainties for grab sampling, short term measurements (charcoal canisters), long term measurements (track detectors) and retrospective measurements (surface traps) are analyzed. The main sources of uncertainties for grab sampling measurements are: systematic bias of reference equipment; random Poisson and non-Poisson errors during calibration; random Poisson and non-Poisson errors during measurements. These sources are also common both for short term measurements (charcoal canisters) and long term measurements (track detectors). Usually during the calibration the high radon concentrations are used (1-5 kBq/m 3 ) and the Poisson random error rarely exceed some percents. Nevertheless the dispersion of measured values even during the calibration usually exceeds the Poisson dispersion expected on the basis of counting statistic. The origins of such non-Poisson random errors during calibration are different for different kinds of instrumental measurements. At present not all sources of non-Poisson random errors are trustworthy identified. The initial calibration accuracy of working devices rarely exceeds the value 20%. The real radon concentrations usually are in the range from some tens to some hundreds Becquerel per cubic meter and for low radon levels Poisson random error can reach up to 20%. The random non-Poisson errors and residual systematic biases are depends on the kind of measurement technique and the environmental conditions during radon measurements. For charcoal canisters there are additional sources of the measurement errors due to influence of air humidity and the variations of radon concentration during the canister exposure. The accuracy of long term measurements by track detectors will depend on the quality of chemical etching after exposure and the influence of season radon variations. The main sources of

  18. Measurement of exhalation rate of radon and radon concentration in air using open vial method

    International Nuclear Information System (INIS)

    Horiuchi, Kimiko; Ishii, Tadashi.

    1991-01-01

    It was recognized that more than half of total exposure dose on human subject is caused by radon and its decay products which originate from naturally occurring radioactive substances (1988 UNSCEAR). Since then the exhalation of radon from the ground surface has received increasing attention. The authors have developed a new method for the determination of radon in natural water using toluene extraction of radon and applying a liquid scintillation counter of an integral counting technique which is able to get the absolute counting of radon. During these studies, the authors found out that when a counting vial containing of Liquid scintillator (LS)-toluene solution, without a lid, is exposed to the atmosphere for a while, dissolution of radon clearly occurs due to high solubility of radon into toluene layer. To extend this finding for the determination of radon in the atmosphere, the authors devised a new method to actively collect the atmosphere containing radon in a glass bottle by discharging a definite amount of water in it, which is named as open-vial dynamic method. The radon concentration can be easily calculated after the necessary corrections such as the partition coefficient and others. Applying proposed method to measure the radon exhalation rate from the ground surface and radon concentration in air of the dwelling environment, radioactive mineral spring zone and various geological formation such as granitic or sedimentary rocks. (author)

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

    Science.gov (United States)

    Farkas, Árpád; Balásházy, Imre

    2015-04-01

    A more exact determination of dose conversion factors associated with radon progeny inhalation was possible due to the advancements in epidemiological health risk estimates in the last years. The enhancement of computational power and the development of numerical techniques allow computing dose conversion factors with increasing reliability. The objective of this study was to develop an integrated model and software based on a self-developed airway deposition code, an own bronchial dosimetry model and the computational methods accepted by International Commission on Radiological Protection (ICRP) to calculate dose conversion coefficients for different exposure conditions. The model was tested by its application for exposure and breathing conditions characteristic of mines and homes. The dose conversion factors were 8 and 16 mSv WLM(-1) for homes and mines when applying a stochastic deposition model combined with the ICRP dosimetry model (named PM-A model), and 9 and 17 mSv WLM(-1) when applying the same deposition model combined with authors' bronchial dosimetry model and the ICRP bronchiolar and alveolar-interstitial dosimetry model (called PM-B model). User friendly software for the computation of dose conversion factors has also been developed. The software allows one to compute conversion factors for a large range of exposure and breathing parameters and to perform sensitivity analyses. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Radon in indoor air. Health risk, measurement methods and remedial measures

    International Nuclear Information System (INIS)

    Strand, T.

    1996-02-01

    Radon in indoor air is the main source of ionizing radiation in Norway. The booklet contains a presentation of radon sources, measurement methods, indoor radon concentrations, action levels, health risk and remedial measures

  1. 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

  2. Rehabilitation Measures against radon gas entry

    International Nuclear Information System (INIS)

    Frutos Vazquez, Borja; Olaya Adan, Manuel; Esteban Saiz, Jose Luis

    2011-01-01

    Radon gas is a pathological agent for inhabitants of buildings where it is present. Due to its origin in uranium decay chain, it bears radioactive effects that inside human body lead to higher risks of developing lung cancer. It comes from soils containing granite masses or other substrates containing uranium. It enters through common material used in constructions, such as concrete ground slabs, basement walls, etc. In order to avoid such gas immission into inhabited rooms, several measurements cab be considered for existing buildings. This study intends to show the results obtained for radon reductions by means of different constructive solutions, already designed and executed so as to stop radon gas immission into a prototype building constructed for this specific purpose

  3. Indoor radon measurements and radon prognosis for the province of Kymi, southeastern Finland

    International Nuclear Information System (INIS)

    Pennanen, M.; Maekelaeinen, I.; Voutilainen, A.

    1996-12-01

    The purpose of the regional radon prognosis is to classify areas with different levels of radon risk. The radon prognosis gives the percentages of future homes expected to have indoor radon concentrations exceeding the levels of 200 and 400 Bq/m 3 . It is assumed that no protection against the entry of radon is used in construction. In this study about 5900 indoor radon measurements made in single family houses, semi-detached houses and row houses were used. Data on the location, geology and construction of buildings were determined from maps and questionnaires. An empirical statistical model, the adjusted indoor radon measurements and geological data were used to assess the radon risk from soil and bedrock in different areas. The building sites of the province of Kymi were divided into thirteen sub-areas. The radon prognosis are calculated for the most radon-prone foundation types including 1) houses with a slab-on-grade and 2) houses with a basement or hillside houses with open stairwells between basement and first floor. The radon levels are generally greater in the western part of the area. The radon risk is highest in gravel-dominated esker areas in southwestern, western (in Pyhtaa, Kotka, Anjalankoski, litti, Valkeala) and central (Taipalsaari) parts of the area. The radon risk is also high in some bedrock and till areas, also in southwestern and western parts of the area. In these areas the level of 200 Bq/m 3 will be exceeded in 80 % of new houses. About half of the future houses in these areas will have indoor radon concentrations exceeding 400 Bq/m 3 . The radon risk is lowest in the eastern part of the province of Kymi in every soil type. In this area the level of 200 Bq/m 3 will be exceeded in 30 % of new houses. Below 10 % will exceed 400 Bq/m 3 . (orig.) (14 refs.)

  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. 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

  6. 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.)

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

    International Nuclear Information System (INIS)

    Fei, Lin.

    1996-04-01

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

  8. Radon in balneology - measurement of radon retention by patients and radiation protection for personell

    International Nuclear Information System (INIS)

    Just, G.; Falkenbach, A.; Grunewald, W.A.; Philipsborn, H. von

    2001-01-01

    In radon balneology patients are exposed to radon either from water or air through the skin or through inhalation. Drinking radon water was not included in the study. Previously, the radon transfer has been determined for an estimate of the medically active amount of radon retained in the patient. A simpler approach of measuring radon in expiration under and after exposure has now been standardised and applied to probands under different conditions of exposure. In addition, radon decay products were measured in sweat, saliva and in the skin. Experimental parameters were evaluated for a comparison of different concentrations observed under different conditions. Results are likely to improve both therapy for patients and radiation protection for members of the personnel. (orig.) [de

  9. Difficulties in radon measurements at workplaces

    International Nuclear Information System (INIS)

    Kavasi, Norbert; Kovacs, Tibor; Nemeth, Csaba; Szabo, Tibor; Gorjanacz, Zoran; Varhegyi, Andras; Hakl, Jozsef; Somlai, Janos

    2006-01-01

    Different legislation systems can be found in the world concerning radon levels at workplaces. Following the European Union suggestion, a reference level for radon concentration in the air at workplaces was established in several European countries. In Hungary, the relevant legislation has come into effect on 1 January 2003. The determination of average radon concentration might present a problem, especially in places where the monthly average concentrations vary to a great extent. For example, the monthly averages measured in a hospital cave used for treating respiratory diseases showed a 24-fold difference depending on the chosen month. In such cases, attention should be paid when choosing the months and using the results of measurements for dose assessment. Another uncertainty emerges when estimating the annual dose, based on the data coming from long-term measurements, usually using integrated methods such as track detectors. There is a considerable difference between the averages measured during the working hours and over the total time (including nights and weekends), mostly in the cases of rooms with frequent air change like schools, kindergartens and ventilated workplaces. This can lead to a significant overestimation in dose calculation. Special attention needs to be paid to workplaces such as mines, tunnels and open air uranium tailings sites. This paper discusses the possible inaccuracies caused by the improper selection of time periods and methods in the measurements of the average radon concentration at workplaces

  10. Radon dose and aerosols

    International Nuclear Information System (INIS)

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

    2000-01-01

    The equilibrium factor value (F) was measured in the NRPB radon chamber and the corresponding track density ratio (r = D/D 0 ) of bare (D) and diffusion (D 0 ) LR-115 nuclear track detectors was determined, as well as the regression equation F(r). Experiments with LR-115 nuclear track detectors and aerosol sources (burning candle and cigarette) were carried out in the Osijek University radon chamber and afterwards an empirical relationship between the equilibrium factor and aerosol concentration was derived. For the purpose of radon dose equivalent assessment, procedures for determining the unattached fraction of radon progeny were introduced using two nuclear track detectors. (author)

  11. Technique and equipment for measuring volume activity of radon in the air of radon laboratories and clinics

    International Nuclear Information System (INIS)

    Vorob'ev, I.B.; Krivokhatskij, A.S.; Nekrasov, E.V.; Nikolaev, V.A.; Potapov, V.G.; Terent'ev, M.V.

    1990-01-01

    Usability of a new equipment-technique combination for measuring radon activity in the air of radon laboratories and balneological clinics is studied. The complex includes nitrate-cellulose detector, radon chamber, Aist, Istra type spark counters and technique of spark counting. The method sensitivity is 50 Bqxm 3 , the error is 30%. Usability and advisability of track method in radon laboratories and balneological clinics for simultaneous measurement in several points of integral volumetric radon activities are confirmred. The method permits to carry out rapid and accurate bulk investigations. The results of determining mean volumetric radon activity in the air in different points of radon laboratory and radon clinics are presented

  12. Indoor radon measurements in Mexico City

    Energy Technology Data Exchange (ETDEWEB)

    Espinosa, G. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Apartado Postal 20364, 01000 Mexico, D.F. (Mexico)], E-mail: espinosa@fisica.unam.mx; Golzarri, J.I. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Apartado Postal 20364, 01000 Mexico, D.F. (Mexico); Bogard, J. [Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831-6480 (United States); Gaso, I. [Instituto Nacional de Investigaciones Nucleares, Apartado Postal 18-1027, 11801 Mexico, D.F. (Mexico); Ponciano, G. [Facultad de Medicina, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, 04510 Mexico, D.F. (Mexico); Mena, M.; Segovia, N. [Instituto de Geofisica, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, 04510 Mexico, D.F. (Mexico)

    2008-08-15

    Mexico City is one of the most populated cities in the world with almost 22 million inhabitants, located at an altitude of 2200 m. The old city was founded on an ancient lake and the zone is known by its high seismicity; indoor radon determination is an important public health issue. In this paper the data of indoor radon levels in Mexico City, measured independently by two research groups, both using Nuclear Track Detector systems but different methodologies, are correlated. The measurements were done during similar exposure periods of time, at family houses from the political administrative regions of the city. The results indicate a correlation coefficient between the two sets of data of R=0.886. Most of the differences between the two sets of data are inherent to houses having extreme (very high or very low indoor radon) included in the statistics of each group. The total average indoor radon found in Mexico City considering the two methods was 87Bqm{sup -3}.

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

    Science.gov (United States)

    Bonotto, D M; Mello, C B

    2006-01-01

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

  14. Activity measurements of radon from construction materials.

    Science.gov (United States)

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

    2012-07-01

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

  15. Radon measurements of groundwater in Mexico

    International Nuclear Information System (INIS)

    Espinosa, G.; Golzarri, J.I.; Cortes, A.

    1991-01-01

    Radon measurement has important applications in hydrogeological studies. Specifically, radon measurement is used to determine the fluctuations of the piezometric levels in groundwater and, in some cases, the path of the water, which is one of the key parameters for evaluating hydrogeological resources. Water from springs and deep wells in the Basin of Mexico and the valley of San Luis Potosi were sampled, measured and analyzed by previous authors. In this work, a method for measuring 222 Rn in groundwater by using a passive detector is presented and the results are compared with a similar experiment performed at the same time, using a dynamic method. The aim of the work is to develop a method for detecting, evaluating and measuring the 222 Rn in groundwater by using SSNTD technology. (author)

  16. Moisture dependence of radon transport in concrete : Measurements and modeling

    NARCIS (Netherlands)

    Cozmuta, [No Value; van der Graaf, ER; de Meijer, RJ

    2003-01-01

    The moisture dependence of the radon-release rate of concrete was measured under well controlled conditions. It was found that the radon-release rate almost linearly increases up to moisture contents of 50 to 60%. At 70 to 80% a maximum was found and for higher moisture contents the radon-release

  17. Indoor radon measurements in Adelaide, South Australia

    International Nuclear Information System (INIS)

    Paix, D.

    1989-01-01

    In 1986 a study of radon levels in homes in Melbourne was made, using activated charcoal to adsorb the gas from indoor air. Cups containing 25g of activated charcoal were exposed for periods of nominally 7 days. The cups were sealed and the accumulated activity was measured by gamma counting. Cup activity was related to ambient radon concentration by calibrations done in the Australian Radiation Laboratory's radon reference chamber. This work was continued in Adelaide, South Australia (S.A.) between July and November 1986 using the same methods. Cups were exposed in their homes by 213 volunteers from the staff of the S.A. Institute of Technology and the S.A. Health Commission. The median concentration of radon in air was 10 Bq/m 3 , with 90% of values below 35 Bq/m 3 , and 100% below 75 Bq/m 3 . The lower bound of the distribution is poorly defined because of inadequate counting statistics. 4 refs., 6 figs

  18. The Radon Book. Preventive measures in new buildings

    International Nuclear Information System (INIS)

    Clavensjoe, Bertil; Aakerblom, Gustav

    2004-01-01

    This book describes in text and picture how one can prevent that the radon concentrations in new buildings become to high. The book's centre of gravity lies on how to build in order to prevent that radon gas from the ground enters the building. The book contains extensive information about ground radon and how to examine the ground before constructing a new building. Release of radon from ground water and construction material is treated, as well as technology for measurement of radon and gamma radiation. The book presents current threshold values/recommended values for radon and the authorities' regulations and recommendations. The book is directed to persons who professionally need knowledge about radon and how to prevent that radon is accumulated in new buildings

  19. Result of the intercomparison exercise on radon measuring instruments and radon detectors 'bev- radon ring 2005'

    Energy Technology Data Exchange (ETDEWEB)

    Baumgartner, A. [Vienna Univ. of Technology, Atominstitut, Wien (Austria); Maringer, F.J.; Michai, P.; Kreuziger, M. [BEV-Federal Office of Metrology and Surveying, Wien (Austria)

    2006-07-01

    In spring 2005 the Federal Office of Metrology and Surveying (B.E.V.) invited all in Austria working radon measuring institutes to an intercomparison exercise at the radon calibration laboratory in the Arsenal. The aim of this intercomparison was on the one hand an objective inquiry and documentation of the current metrological potential on the section of radon measurement in Austria - both quantitative and qualitative- and on the other hand an initiative for the participating laboratories to optimize and improve their applied calibration-, measurement and analyse technique. Ten contacted Austrian radon laboratories were prepared to participate on the radon intercomparison exercise. The intercomparison exercise was carried out from 14. till 29. June at the radon calibration laboratory in the Arsenal of the B.E.V.. As radon emanation source a five stepped arranged, at the Arsenal built radon source was used. The source ( A.D.O.T.T.O. 1 is filled with a certified Ra- 226-standard solution of the Czech Metrological Institute (C.M.I.), Prag. A simple statistic based model was used for the evaluation and assessment of the results from the participants, which consider the statistic nature of the radioactive decay combined uncertainty. Altogether 183 measuring instruments participated the intercomparison exercise. Two reference measuring instruments, 22 active and 159 passive measuring instruments. The active measuring instruments formed 6 types of instruments and as passive radon detectors were 7 different types used from the participants. The positioning of the radon measuring instruments and detectors in the radon calibration laboratory was executed in regard to statistic points of view. From the active measuring instruments 17 could qualify and from the passive methods six from eight participants were in compliance to the given criteria. Radon measurements, which could have financial and economics relating implications (e.g. architectural redevelopment or

  20. Long-term Radon Levels and Equilibrium Factor in Some Spanish Workplaces Measured with a Passive Integrating Detector

    International Nuclear Information System (INIS)

    Baixeras, C.; Amgarou, K.; Font, Ll.; Domingo, C.

    1999-01-01

    The measurement of long-term radon levels and equilibrium factor is important to estimate the annual averaged dose due to radon progeny inhalation indoors. According to the European Union directive 96/26/EURATOM it is necessary to control the radon level in workplaces. This paper presents the radon concentration and equilibrium factor values obtained in some workplaces from the Barcelona area with a passive integrating dosemeter exposed for two months. The dosemeter consists of two Makrofol-DE nuclear etched track foils, one within a diffusion chamber and the other one bare, allowing the separated measurement of 222 Rn (C 0 ) and 214 Po (C 4 ) activity concentration respectively. The equilibrium factor is estimated from the disequilibrium degree (k 4 = C 4 /C 0 ). A description of the dosemeter and the methodology used, and an estimation of the annual dose received for the workers at the different workplaces are presented. (author)

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

    International Nuclear Information System (INIS)

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

    1999-01-01

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

  2. Measurements of radon and chemical elements: Popocatepetl volcano; Mediciones de radon y elementos quimicos: Volcan Popocatepetl

    Energy Technology Data Exchange (ETDEWEB)

    Pena, P.; Segovia, N.; Lopez, B.; Reyes, A.V. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Armienta, M.A.; Valdes, C.; Mena, M. [IGFUNAM, Ciudad Universitaria, 04510 Mexico D.F. (Mexico); Seidel, J.L.; Monnin, M. [UMR 5569 CNRS Hydrosciences, Montpellier (France)

    2002-07-01

    The Popocatepetl volcano is a higher risk volcano located at 60 Km from Mexico City. Radon measurements on soil in two fixed seasons located in the north slope of volcano were carried out. Moreover the radon content, major chemical elements and tracks in water samples of three springs was studied. The radon of soil was determined with solid detectors of nuclear tracks (DSTN). The radon in subterranean water was evaluated through the liquid scintillation method and it was corroborated with an Alpha Guard equipment. The major chemical elements were determined with conventional chemical methods and the track elements were measured using an Icp-Ms equipment. The radon on soil levels were lower, indicating a moderate diffusion of the gas across the slope of the volcano. The radon in subterranean water shown few changes in relation with the active scene of the volcano. The major chemical elements and tracks showed a stable behavior during the sampling period. (Author)

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

    Energy Technology Data Exchange (ETDEWEB)

    Fazal-ur-Rehman E-mail: fazalr@kfupm.edu.sa; Al-Jarallah, M.I.; Musazay, M.S.; Abu-Jarad, F

    2003-12-01

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

  4. Measurement of the radon exhalation rate from the medium surface by tracing the radon concentration

    International Nuclear Information System (INIS)

    Yanliang Tan; Detao Xiao

    2013-01-01

    The paper will present a method based on the accumulation chamber technique for measuring of radon exhalation from the medium surface. A radon monitor traces the change of radon concentration in the accumulation chamber, and then the radon exhalation can be obtained accurately through linear fit. Based on our recent experiments, the radon exhalation rate from the medium surface obtained from this method is in good agreement with the actual exhalation rate of our simulation facility. This method is superior to the competition method which obtains the radon exhalation through the exponential fit by an external PC-system. The calculation for the exponential fit is very easy by computer and related software. However, for portable instruments, the single chip microcomputer can't calculate the exponential fit rapidly. Thus, this method is usable for developing the new portable instrument to classify building materials, etc. (author)

  5. 222Rn and short live progeny in atmospheric environment. Origin and measurement techniques

    International Nuclear Information System (INIS)

    Charuau, J.; Labed, V.; Robe, M.C.; Thevenin, J.C.; Fazileabasse, J.; Klein, D.; Heleschewitz, H.; Tymen, G.; Aubert, C.; Gibaud, C.

    1996-01-01

    Radon is the main source of man's exposure to natural ionizing radiation. This document summarizes the general knowledge of the origin of radon 222 and its development in various air environments. It presents several methods for measuring radon activity concentration and the potential alpha energy from its short life daughters. It has been prepared by the commission M60-3, of the Office for the standardization of nuclear equipments (BNEN in French) under the French association for standardization (AFNOR in French). (author)

  6. 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 ...

  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. Continuous measurements of soil radon under regular field conditions

    International Nuclear Information System (INIS)

    Font, LL

    1999-01-01

    Continuous soil radon measurements were performed in the frame of an European Community-radon network using the Clipperton II detector. It has been found that in some periods, soil radon levels obtained with one Clipperton II probe are very different from those obtained with another probe placed at the same depth but a short distance apart. It has been also found that the response of the probes to a sudden change of radon concentration is controlled by the diffusion process along the bottom tube of the probe. Therefore, this study shows that the experimental data can be attributed to the natural behaviour of soil radon

  9. Measurements and statistical analyses of indoor radon concentrations in Tokyo and surrounding areas

    International Nuclear Information System (INIS)

    Sugiura, Shiroharu; Suzuki, Takashi; Inokoshi, Yukio

    1995-01-01

    Since the UNSCEAR report published in 1982, radiation exposure to the respiratory tract due to radon and its progeny has been regarded as the single largest contributor to the natural radiation exposure of the general public. In Japan, the measurement of radon gas concentrations in many types of buildings have been surveyed by national and private institutes. We also carried out the measurement of radon gas concentrations in different types of residential buildings in Tokyo and its adjoining prefectures from October 1988 to September 1991, to evaluate the potential radiation risk of the people living there. One or two simplified passive radon monitors were set up in each of the 34 residential buildings located in the above-mentioned area for an exposure period of 3 months each. Comparing the average concentrations in the buildings of different materials and structures, those in the concrete steel buildings were always higher than those in the wooden and the prefabricated mortared buildings. The radon concentrations were proved to become higher in autumn and winter, and lower in spring and summer. Radon concentrations in an underground room of a concrete steel building showed the highest value throughout our investigation, and statistically significant seasonal variation was detected by the X-11 method developed by the U.S. Bureau of Census. The values measured in a room at the first floor of the same concrete steel building also showed seasonal variation, but the phase of variation was different. Another multivariate analysis suggested that the building material and structure are the most important factors concerning the levels of radon concentration among other factors such as the age of the building and the use of ventilators. (author)

  10. Measurement of radon activity concentration in buildings

    International Nuclear Information System (INIS)

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

    2010-01-01

    Radon exposure, along with medical-related exposure, is the leading source of exposure to ionising radiation for the French population. Measurement campaigns are done in the action plan, drawn up by the French nuclear safety authority (ASN), in cooperation with the French directorate for housing, town planning and countryside (DHUP), the French radiation protection and nuclear safety institute (IRSN), the French health monitoring institute (InVS) and the French scientific and technical centre for construction (CSTB). The review of 2005-2008 measurement campaign shows that of the 7356 buildings screened, 84.8% had activity concentration levels below the 400 Bq/m 3 action level. For the other buildings (15.2%), action will be required to reduce human exposure to radon, possibly including building renovation/redevelopment work. In the 1999-2002 measurement campaign,12% of the 13,000 buildings screened had a radon activity concentration level higher than 400 Bq/m 3 . In addition, the ASN and the French general directorate of labour (DGT) are continuing to work on drawing up regulations for occupational risk management. The second national health and environment plan (PNSE 2) was published on 26 June 2009. It follows on from the actions initiated in PNSE 1, a document provided for under the Public Health Act dated 9 August 2004 and under the French 'Grenelle' environmental agreements. On the basis of guidelines laid out in PNSE 2, a radon action plan for 2009-2012 will be drawn up, enabling some of the actions to be continued, particularly in the fields of new building projects and dwellings. (author)

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

    International Nuclear Information System (INIS)

    Zunic, Z.S.; Yarmoshenko, I.V.; Kelleher, K.; Paridaens, J.; Mc Laughlin, J.P.; Celikovic, I.; Ujic, P.; Onischenko, A.D.; Jovanovic, S.; Demajo, A.; Birovljev, A.; Bochicchio, F.

    2007-01-01

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

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

    International Nuclear Information System (INIS)

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

    2004-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-02-09

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

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

    International Nuclear Information System (INIS)

    Hoetzl, H.; Winkler, R.

    1996-01-01

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

  15. In-field radon measurement in water: a novel approach

    International Nuclear Information System (INIS)

    Talha, S.A.; Meijer, R.J. de; Lindsay, R.; Newman, R.T.; Maleka, P.P.; Hlatshwayo, I.N.

    2010-01-01

    This paper presents a novel approach of measuring radon in-water in the field by inserting a MEDUSA gamma-ray detector into a 210 L or 1000 L container. The experimental measurements include investigating the effect of ambient background gamma-rays on in-field radon measurement, calibrating the detector efficiency using several amounts of KCl salt dissolved in tap water, and measuring radon in borehole water. The results showed that there is fairly good agreement between the field and laboratory measurements of radon in water, based on measurements with Marinelli beakers on a HPGe detector. The MDA of the method is 0.5 Bq L -1 radon in-water. -- Research highlights: →Radon-in-water, large volume container, in-field measurements, MEDUSA gamma-ray detection system.

  16. 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

  17. Determination of air-loop volume and radon partition coefficient for measuring radon in water sample.

    Science.gov (United States)

    Lee, Kil Yong; Burnett, William C

    A simple method for the direct determination of the air-loop volume in a RAD7 system as well as the radon partition coefficient was developed allowing for an accurate measurement of the radon activity in any type of water. The air-loop volume may be measured directly using an external radon source and an empty bottle with a precisely measured volume. The partition coefficient and activity of radon in the water sample may then be determined via the RAD7 using the determined air-loop volume. Activity ratios instead of absolute activities were used to measure the air-loop volume and the radon partition coefficient. In order to verify this approach, we measured the radon partition coefficient in deionized water in the temperature range of 10-30 °C and compared the values to those calculated from the well-known Weigel equation. The results were within 5 % variance throughout the temperature range. We also applied the approach for measurement of the radon partition coefficient in synthetic saline water (0-75 ppt salinity) as well as tap water. The radon activity of the tap water sample was determined by this method as well as the standard RAD-H 2 O and BigBottle RAD-H 2 O. The results have shown good agreement between this method and the standard methods.

  18. Determination of air-loop volume and radon partition coefficient for measuring radon in water sample

    International Nuclear Information System (INIS)

    Kil Yong Lee; Burnett, W.C.

    2013-01-01

    A simple method for the direct determination of the air-loop volume in a RAD7 system as well as the radon partition coefficient was developed allowing for an accurate measurement of the radon activity in any type of water. The air-loop volume may be measured directly using an external radon source and an empty bottle with a precisely measured volume. The partition coefficient and activity of radon in the water sample may then be determined via the RAD7 using the determined air-loop volume. Activity ratios instead of absolute activities were used to measure the air-loop volume and the radon partition coefficient. In order to verify this approach, we measured the radon partition coefficient in deionized water in the temperature range of 10-30 deg C and compared the values to those calculated from the well-known Weigel equation. The results were within 5 % variance throughout the temperature range. We also applied the approach for measurement of the radon partition coefficient in synthetic saline water (0-75 ppt salinity) as well as tap water. The radon activity of the tap water sample was determined by this method as well as the standard RAD-H 2 O and BigBottle RAD-H 2 O. The results have shown good agreement between this method and the standard methods. (author)

  19. Accurate measurement of indoor radon concentration using a low-effective volume radon monitor

    International Nuclear Information System (INIS)

    Tanaka, Aya; Minami, Nodoka; Mukai, Takahiro; Yasuoka, Yumi; Iimoto, Takeshi; Omori, Yasutaka; Nagahama, Hiroyuki; Muto, Jun

    2017-01-01

    AlphaGUARD is a low-effective volume detector and one of the most popular portable radon monitors which is currently available. This study investigated whether AlphaGUARD can accurately measure the variable indoor radon levels. The consistency of the radon-concentration data obtained by AlphaGUARD is evaluated against simultaneous measurements by two other monitors (each ∼10 times more sensitive than AlphaGUARD). When accurately measuring radon concentration with AlphaGUARD, we found that the net counts of the AlphaGUARD were required of at least 500 counts, <25% of the relative percent difference. AlphaGUARD can provide accurate measurements of radon concentration for the world average level (∼50 Bq m -3 ) and the reference level of workplace (1000 Bq m -3 ), using integrated data over at least 3 h and 10 min, respectively. (authors)

  20. Optimized collection, storage and measurement of radon and radon decay products - school experiments

    International Nuclear Information System (INIS)

    Philipsborn, H. von; Geipel, R.; Just, G.

    1998-01-01

    Schools are expected more than ever to teach in physics and chemistry an understanding of radioactivity in its many aspects. Simple experiments on the occurrence, the measurement and the properties of radionuclides are necessary for true understanding. Such experiments are now possible with novel methods of collection and storage of ubiquitous radon and radon decay products from air, water and solids. (orig.) [de

  1. Reinforced natural radioactivity: the case of radon measurement

    International Nuclear Information System (INIS)

    Bernhard, S.; Desray, M.

    2009-01-01

    Summarizing a presentation of radon measurement instruments, of their use and of the interpretation of their results, the authors briefly recall the origin of exposures to radon (geological or occupational), indicate the three types of control (detection of presence of radon, search for and characterization of sources and transfer ways, worker dosimetric follow-on) and the three types of measurement (selective, integrated or continuous), and evoke the range of measurement instruments

  2. Effectiveness of ventilation improvements as a protective measure against radon

    International Nuclear Information System (INIS)

    Hoving, P.; Arvela, H.

    1993-01-01

    Radon reduction rates for ventilation improvement measures vary considerably. In 70% of the cases studied, further mitigation is needed to reach a level of 400 Bq/m 3 . Ventilation measures in crawl spaces and basements have resulted in reduction rates of up to 90%, though more typically 30-70%. Installing new mechanical systems in dwellings has resulted in 20-80% reduction rates. If fan use or fan efficiency is increased, radon levels can be reduced as much as when new systems are installed. Increasing fresh-air supply through vents or window gaps reduces radon concentrations 10-40%. Low ventilation rates, measured after mitigation using the passive per fluorocarbon tracer gas method, seem to be accompanied by also low radon reduction rates. Multiple zone tracer gas measurements were conducted in order to reveal radon entry from the soil and radon transport between zones. (orig.). (3 refs., 3 figs., 2 tabs.)

  3. Measurement of radon exhalation rate and soil gas radon concentration in areas of southern Punjab (Pakistan)

    International Nuclear Information System (INIS)

    Mujahid, S. A.; Hussain, S.; Ramzan, M.

    2010-01-01

    Plastic track detectors were used to measure the radon concentration and exhalation rate from the soil samples. The samples were collected from areas of southern Punjab (Pakistan). In a laboratory experiment, passive alpha dosemeters were installed inside cylindrical bottles containing the soil samples. The radon concentrations and the radon exhalation rate were found in the ranges of 34±7 to 260±42 Bq m -3 and 38±8 to 288±46 mBq m -2 h -1 , respectively. The on-site measurements of radon in the soil gas were also carried out in these areas using a scintillation alpha counter. The concentration of radon in the soil gas was found in the range of 423±82-3565±438 Bq m -3 . (authors)

  4. 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)

  5. Continuous measurements of outdoor radon concentrations

    International Nuclear Information System (INIS)

    Iida, T.; Ikebe, Y.; Suzuki, K.; Ueno, K.; Komura, K.; Kato, I.; Jin Yihe

    1993-01-01

    The authors studied and developed an electrostatic 222 Rn monitor and have measured continuously outdoor radon ( 222 Rn) concentrations at Nagoya University since 1985. Four 222 Rn monitors were newly constructed to measure outdoor 222 Rn concentrations at other locations. The 222 Rn concentrations at Nagoya and Kasugai show a clear diurnal variation in autumn, and a seasonal pattern of a spring-summer minimum and a autumn-winter maximum. The results at Toki are the same pattern as that at Nagoya except spring. The concentrations at Kanazawa show a slight seasonal variation. A clear diurnal variation is observed in summer. (4 figs.)

  6. 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...

  7. Nuclear tracks in solids and gas radon measurements

    International Nuclear Information System (INIS)

    Espinosa, G.

    2007-01-01

    Full text: The Department of Energy (DOE), the Environmental Protection Agency (EPA) in USA, and the European Community, have dedicated significant budget to the Radon study, its health effects and remedial actions for controlling and achieving lower levels, in these cases, nationwide research programs have been organized. With the aim to contribute on the radon levels knowledge in our country, the Applied Dosimetry Project at the Physics Institute of the University of Mexico has developed an indoor and outdoor radon measurement methodology. In this paper a passive radon detector device based on CR-39 polycarbonate for use in radon research and routine measurements is presented. As well the methodology for the track formation, automatic reading system, calibration procedure and measurements in a different location, are shown in this work. The results had been compared with dynamic detection systems, and another methodologies and research groups in order to have a high confidence in the radon levels reported. (Author)

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

    Science.gov (United States)

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

    2013-12-01

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

  9. Interim protocols for screening and follow-up radon and radon-decay product measurements. Interim report

    International Nuclear Information System (INIS)

    Magno, P.; Nyberg, P.; Ronca-Battista, M.

    1987-02-01

    This report outlines the recommended strategy for assessing indoor radon levels and provides guidance for interpreting measurement results. It recommends a two-step strategy for making the fewest measurements possible, while ensuring that radon concentrations are not seriously underestimated

  10. Measurement of mean radon concentrations in the Tokai districts

    International Nuclear Information System (INIS)

    Iida, Takao; Ikebe, Yukimasa; Yamanishi, Hirokuni

    1989-01-01

    This paper describes an electrostatic integrating radon monitor designed for the environmental radon monitoring and longterm measurements of mean radon concentrations in outdoor and indoor air. The position of the collecting electrode within the monitor was determined based on the calculation of the internal electric field. The radon exchange rate between the monitor and the outside air through the filter was 0.75 h -1 . The exchange rate can make the radon concentration inside the monitor to follow thoroughly the outside concentration. Since the electrostatic collection of RaA + ( 218 Po + ) atoms depends on the humidity of the air, the inside of the monitor was dehumidified with a diphosphorus pentaoxide (P 2 O 5 ) drying agent which is powerful and dose not absorb radon gas. From the relationship between track density and radon exposure, the calibration factor was derived to be 0.52 ± 0.002 tracks cm -2 (Bq m -3 h) -1 . The detection limit of mean radon level is 1.2 Bq m -3 for an exposure time fo 2 months. The mean radon concentrations in various environments were measured through the year using the monitors this developed. The annual mean outdoor radon level in the Tokai districts was 7.0 Bq m -3 . The mean radon concentrations was found to vary from 3.5 to 11.7 Bq m -3 depending upon the geographical conditions even in this relatively small region. The annual indoor radon concentrations at Nagoya and Sapporo ranged from 6.4 to 11.9 Bq m -3 and from 15.5 to 121.1 Bq m -3 , respectively, with the type of building material and the ventilation rate. The mean radon concentrations in tightly built houses selected at Sapporo are about 10 times as high as those in drafty houses at Nagoya. (author)

  11. Development of a PIN diode based on-line measurement system for Radon (222Rn) and Thoron (220Rn) in environment

    International Nuclear Information System (INIS)

    Ashokkumar, P.; Chaudhury, Probal; Sumesh, C.G.; Sahoo, B.K.; Gaware, J.J.; Mayya, Y.S.

    2014-01-01

    Radon, thoron and their progenies are universally present in outdoor air, and can reach higher levels in indoor air due to poor ventilation. Several instruments have been developed for accurate measurement of radon and thoron in the environment. Semiconductor detector based system employing spectroscopic method has been proved to be the best among them. A PIN diode based electrostatic collection type online real-time instrument has been developed in Bhabha Atomic Research Centre for simultaneous measurement of radon and thoron in an environment while both 222 Rn and 220 Rn are present. This system can be used for determination of radon and thoron concentrations at residence or workplace. Furthermore, since the 222 Rn and 220 Rn are differentiated from each other through spectroscopy, this monitor can be used even in a mixed radon/thoron environment

  12. Measurements of radon and chemical elements: Popocatepetl volcano

    International Nuclear Information System (INIS)

    Pena, P.; Segovia, N.; Lopez, B.; Reyes, A.V.; Armienta, M.A.; Valdes, C.; Mena, M.; Seidel, J.L.; Monnin, M.

    2002-01-01

    The Popocatepetl volcano is a higher risk volcano located at 60 Km from Mexico City. Radon measurements on soil in two fixed seasons located in the north slope of volcano were carried out. Moreover the radon content, major chemical elements and tracks in water samples of three springs was studied. The radon of soil was determined with solid detectors of nuclear tracks (DSTN). The radon in subterranean water was evaluated through the liquid scintillation method and it was corroborated with an Alpha Guard equipment. The major chemical elements were determined with conventional chemical methods and the track elements were measured using an Icp-Ms equipment. The radon on soil levels were lower, indicating a moderate diffusion of the gas across the slope of the volcano. The radon in subterranean water shown few changes in relation with the active scene of the volcano. The major chemical elements and tracks showed a stable behavior during the sampling period. (Author)

  13. 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

  14. Measurements of radon activity concentrations in air at Niska spa

    International Nuclear Information System (INIS)

    Adrovic, F.; Vuckovic, B.; Ninkovic, M.

    2004-01-01

    Radon activity concentrations in air were measured in the recreational-tourist center of Niska Banja. Alpha Guard PQ 2000/ MC50 instrumentation (Genitron instruments, Frankfurt) was used. The observed indoor radon concentrations in the air of the Radon Hotel pool lay within the range of 0.980-1.908 kBq/m 3 and were directly dependent on the exhalation of radon from thermomineral waters. Radon concentrations were also measured outdoors, at locations for capping thermomineral water, as well as at locations for draining used water from the Radon Hotel pool. Outdoor radon concentrations as high as over 500 Bq/m 3 were observed. Gamma dose rates were measured in parallel and found to lie within the range of 72-420 nSv/h. The gamma doses correlated well with the observed radon levels. The largest gamma dose rates in air were measured in the pool of Radon Hotel and at the site where this thermomineral water is being capped

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

    International Nuclear Information System (INIS)

    Misdaq, M.A.; Flata, K.

    2003-01-01

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

  16. Radon measurements in the interior of the great pyramid

    Energy Technology Data Exchange (ETDEWEB)

    Kenawy, M A; Morsy, A A [Ain Shams Univ., Cairo (Egypt). College for Girls

    1991-01-01

    Radon concentration measurements were made in the interior of the great pyramid of ''Cheops'' at Giza. Measurements were carried out using CR-39 as a solid state nuclear track detector. The CR-39 sheets were placed inside the Queen's and King's chambers and along the ascending corridor leading to them. An evaluation of the radon concentration is presented and discussed. (author).

  17. Radon measurements concerning engineering-geological problems in lignite mining

    Energy Technology Data Exchange (ETDEWEB)

    Heinicke, J

    1986-07-01

    Radon measurements have been carried out by the aid of solid-state track detectors at the highwall of a lignite mine in order to forecast the eventual course of a landslide. The measured radon distributions and their changes as a function of time indicated that the slope was geodynamically active, but it was not possible to forecast the rate of sliding.

  18. Radon measurements in the interior of the great pyramid

    International Nuclear Information System (INIS)

    Kenawy, M.A.; Morsy, A.A.

    1991-01-01

    Radon concentration measurements were made in the interior of the great pyramid of ''Cheops'' at Giza. Measurements were carried out using CR-39 as a solid state nuclear track detector. The CR-39 sheets were placed inside the Queen's and King's chambers and along the ascending corridor leading to them. An evaluation of the radon concentration is presented and discussed. (author)

  19. FOLLOW-UP RADON MEASUREMENTS IN 14 MITIGATED SCHOOLS

    Science.gov (United States)

    The report gives results of a determination of the long-term performance of radon mitigation systems installed in U. S. EPA research schools: radon measurements were conducted in 14 schools that had been mitigated between 1988 and 1991. The measurements were made between Februar...

  20. Study on the influence factors about the soil radon measurement

    International Nuclear Information System (INIS)

    Wu Zixiang; Liu Yanbin; Jia Yuxin; Mai Weiji; Liu Xiaolian; Yang Yuhua

    2006-01-01

    Objective: To explore relevant factors about the soil radon measurement and provide gist of formulating correct measure method by studying the way of the soil radon measurement. Methods: Deflation-ionization room standard is adopted. Results: The concentration of soil radon becomes higher with the sample's volume added, it also augmented with the measure depth increased in certain degree; The concentration of soil radon changes little when sample's depth is above 60 cm; The time of deflation has no obvious influence on the concentration of soil radon, but microwave show serious effect on it; The results will be lowered when the desiccant is humidified, raining has the same affection on it; Plant has some impact on it. Conclusion: The measured results will be affected by microwave, oscillate and plant. Sample's volume and depth, soil's humidity can influence it too. The result's veracity can be guaranteed by choosing appropriate sample and measure condition. (authors)

  1. 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 - ...

  2. Evaluation of the open vial method in the radon measurement

    International Nuclear Information System (INIS)

    Lopez del Rio, H.; Davila R, J. I.; Mireles G, F.

    2014-10-01

    The open vial method is a simple technique, under-utilized but that take advantage of the great radon solubility in organic solvents, therefore applies in the measurement of the radon concentration exhaled in soil. The method consists on the exposition to the gas radon of an open vial with scintillating solution. An integral mathematical model for indoors that describes the emanation processes and gas radon exhalation was developed, as well as the radon dissolution in the scintillation liquid, besides obtaining the characteristic parameters of the experimental system proposed for the radon concentration calculation exhaled by soils. Two experimental arrangements were designed with exposition cameras of 12 and 6 L and quantity of different soil. The open vial was prepared with a mixture of 8 ml of deionized water and 12 ml of scintillation liquid OptiPhase Hi Safe 3 in polyethylene vials; the measurements of the dissolved radon were carried out in scintillation liquid equipment. As a result, on average 2.0% of the exhaled radon is dissolved in the open vial and the dissolved fraction is independent of the experimental arrangement. Also was observed that the exposition time does not affect the radon dissolution significantly, in correspondence with the reported in the literature. (Author)

  3. 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)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-12-01

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

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

    International Nuclear Information System (INIS)

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

    1995-01-01

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

  6. Protocol Implementation for Radon Concentration Measurements in Houses in Croatia - Baranja Case

    International Nuclear Information System (INIS)

    Radolic, V.; Miklavcic, I.; Poje, M.; Stanic, D.; Varga Pajtler, M.; Vukovic, B.

    2011-01-01

    The newly established protocol for radon measurements in homes was implemented on the radon survey in houses of Baranja region which was carried out from July 2009 until July 2010. The radon measurements were performed with passive track etched detectors. The method consists of cylindrical plastic vessel and two strippable LR-115 films type II (Kodak-Path, France). This method with two detector films enables the estimation of equilibrium factor as well.Croatian territory is divided in 10 x 10 km 2 cells which were part of a reference grid map which is used in a preparation of European radon concentration map. Detector locations were randomly chosen inside each grid and their number was determined by the number of inhabitants inside (one locations per 350 inhabitants). Radon detectors were exposed for a year in a living room or a bedroom away from strong ventilation and 30 cm from side walls (usually on closet at height of 2 m). After the exposure, detectors were collected and etched in 10 % NaOH aqueous solution at 50 degrees of C for 180 minutes. The tracks were automatically counted using spark counter AIST-2V. The obtained results were in the range from 6 to 355 Bq m -3 with arithmetic mean of 88 Bq m -3 and standard deviation of 69.0 Bq m -3 . The geometric mean was 67.2 Bq m -3 while the geometric standard deviation was 2.1 Bq m -3 . The statistical χ2 -test showed that the empirical frequency distribution for radon in houses of Baranja region belonged to the log-normal distribution. The percentage of houses with radon concentrations between 200 and 400 Bq m -3 was 6.7% and 1.0% of houses have radon concentration above 400 Bq m -3 . The annual effective dose from the indoor radon and its short-lived progenies for the inhabitants of Baranja region (for the average equilibrium factor of 0.53 and occupancy factor of 0.6) was 1.5 mSv. (author)

  7. New apparatus for measuring radon adsorption on solid adsorbents

    International Nuclear Information System (INIS)

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

    1991-01-01

    A new experimental system was designed to measure radon uptake by solid adsorbents from air or other carrier gases/vapors. The total amount of radon adsorbed corresponding to a specific gas-phase concentration was determined by simultaneously measuring the solid-phase and gas-phase concentrations. The system was used to measure radon adsorption isotherms on BPL activated carbon at 288, 298, and 308 K and on silica gel and molecular sieve 13X at 298 K. The isotherms were of type III according to Brunauer's classification. The heat of adsorption data indicated that the BPL activated carbon provided a heterogeneous surface for radon adsorption. The equilibrium data were correlated by the Freundlich equation. In this paper the possible adsorption mechanism and the use of the adsorption isotherms to measure indoor radon concentrations are discussed

  8. Radon: guidance on protective measures for new dwellings

    International Nuclear Information System (INIS)

    1991-01-01

    This report gives guidance for reducing the presence of radon in new dwellings and hence reducing the risk to occupants of exposure to radon. This is a follow-up to the interim guidance of 1988. The report provides comprehensive practical details on the methods of protection including both primary and secondary measures. (UK)

  9. Intercomparison 2003 for Radon measurement services at PSI

    CERN Document Server

    Butterweck, G

    2003-01-01

    Twelve radon measurement services participated in the 2003 Radon Intercomparison Exercise performed at the Reference Laboratory for Radon Gas Activity Concentration Measurements at Paul Scherrer Institut (PSI) during March 13th to 24th, 2003. Ten of these laboratories were approved by the Swiss Federal Office of Public Health and their participation in the intercomparison exercise was a requirement to warrant quality of measurement. Radon gas detectors (etched-track and electret ionisation chambers) and instruments (ionisation chambers and electrostatic precipitation) were exposed in the PSI Radon Chamber in a reference atmosphere with an average radon gas concentration of 1950 Bqm sup - sup 3 leading to a radon gas exposure of 517 kBqhm sup - sup 3. Additional five electret-detectors of an approved measuring service were purchased by the Swiss Federal Office of Public Health for a spot check. Two of these were exposed as described above, two had an exposure of 247 kBqhm sup - sup 3 at an average radon concen...

  10. 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)

  11. 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

  12. Gamma, radon, natural radioactivity measurements in Chile

    International Nuclear Information System (INIS)

    Stuardo, E.

    1997-01-01

    Different natural radiation measurements, performed since 1983, are analysed and discussed regarding the average effective population dose. A decade of absorbed gamma dose measurements in air (1983-93), were carried out using compensated TLD detectors, during long periods of integration time and with a network of 11 stations, along the country, from Arica to the Antarctic territory. An indoor Rn -222 and gamma survey dwellings, in high background zones, underground mines and drinking water was started in 1988 using different kind of detectors, including electret radon chambers. The methods, dose assessments and results are presented and discussed in the frame of worldwide average effective population doses. None of the average effective doses found over the evaluated areas, exceed the comparison levels. (author)

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

    International Nuclear Information System (INIS)

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

    1978-01-01

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

  14. 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)

  15. Method for radon measurement in the subsoil in geothermal prospectus

    International Nuclear Information System (INIS)

    Balcazar G, M.

    1991-02-01

    The present formless describe the technique for radon measurement in the underground, being able to be used as an additional study in the geothermal prospecting. This methodology has been developed in the National Institute of Nuclear Research of Mexico using a film of cellulose nitrate to detect those emanated alpha particles, by the Rn (222). By means of the trace account in this films its settle down the present radon levels in the underground. The present method thinks about as an alternating one to overcome in it leaves the limitations found in the development of the methodology using a radon emanometer ETR-1, of the trade mark SCINTREX. The radon detected by plastics is also an integral method of measuring in a geothermal field that avoids the problems of variations of radon to pluvial precipitations and barometric variations. These variations affect the results strongly when it is used the punctual sampler as it is the ETR-1. (Author)

  16. Measurement of radon permeability through polyethylene membrane using scintillation detector

    Energy Technology Data Exchange (ETDEWEB)

    Ashry, A.H.; Abou-Leila, M. [Department of Physics, Faculty of Education, Ain Shams University, Cairo (Egypt); Abdalla, A.M., E-mail: aymanabdalla62@hotmail.co [Department of Physics, Faculty of Education, Ain Shams University, Cairo (Egypt); Department of Physics, Faculty of Sciences and Arts, Najran University, Najran, P.O. Box. 11001 (Saudi Arabia); Advanced Materials and Nano-Engineering Laboratory (AMNEL), Centre for Advanced Materials and Nano-Engineering (CAMNE), Najran University, Najran, P.O. Box. 11001 (Saudi Arabia)

    2011-01-15

    The permeability of Radon 222 through polyethylene membranes has been studied using activated charcoal technique. The permeability constant of Radon 222 through low-density polyethylene, linear low-density Polyethylene and high density polyethylene samples has been measured. There is a considerable agreement between the values obtained by our method and the method suggested by W. Arafa [2002. Permeability of radon 222 through some materials. Radiat. Meas. 35, 207-211], and SSNTD technique suggested by A. Hafez and G. Somogyi [1986. Determination of radon and thoron permeability through some plastics by track technique. Int. J. Radiat. Appl. Instrum. Nucl. Track Radiat. Meas. 12 (1-6), 697-700]. In this work Radon permeability through different polyethylene membranes has been measured using three different methods, i.e. solid state nuclear track technique, W. Arafa [2002. Permeability of radon 222 through some materials. Radiat. Meas. 35, 207-211]method and our proposed method. In addition to this, in this study, the diffusion coefficient of radon in charcoal as well as solubility of Radon in polyethylene membrane has been taken into consideration.

  17. Low-level radon measurements by nuclear track detectors

    International Nuclear Information System (INIS)

    Koksal, E. M.; Goksel, S. A.; Alkan, H.

    1985-01-01

    In the work to be described here we have developed a passive nuclear track dosimeter to measure the integrated value of indoor radon (Rn-222) over a long period of time. Passive radon dosimeter which we have developed in our laboratories makes use of two small pieces of CR-39 plastic (Allyl diglycol carbonate) as detectors for registering tracks of alpha particles emitted by radon. These CR-39 plastic detectors are fixed on the inside bottom of a cup-shaped polystrene enclosure which is closed at the top by a tissue permeable for gases only. CR-39 detectors exposed to radon gas in the indoor air for a period of six months then are removed and chemically etched to make the alpha particle tracks visible under the microscope. The counts of tracks are evaluated to determine the radon concentration in the air in comparison with the number of tracks produced by a known concentration of radon gas. By using the passive dosimeters developed and the chemical etching procedure descriped here, measurements of indoor radon concentrations were carried out in 45 houses in different districts of the city of Istanbul. In this pilot experiment mean radon concentrations between 0.7 and 3.5 pCi/l have been found in these houses. In order to improve the counting of alpha tracks produced on the detectors a prototype electrochemical etching system in addition to chemical etching, is being developed. (author)

  18. Measurement of radon permeability through polyethylene membrane using scintillation detector

    International Nuclear Information System (INIS)

    Ashry, A.H.; Abou-Leila, M.; Abdalla, A.M.

    2011-01-01

    The permeability of Radon 222 through polyethylene membranes has been studied using activated charcoal technique. The permeability constant of Radon 222 through low-density polyethylene, linear low-density Polyethylene and high density polyethylene samples has been measured. There is a considerable agreement between the values obtained by our method and the method suggested by W. Arafa [2002. Permeability of radon 222 through some materials. Radiat. Meas. 35, 207-211], and SSNTD technique suggested by A. Hafez and G. Somogyi [1986. Determination of radon and thoron permeability through some plastics by track technique. Int. J. Radiat. Appl. Instrum. Nucl. Track Radiat. Meas. 12 (1-6), 697-700]. In this work Radon permeability through different polyethylene membranes has been measured using three different methods, i.e. solid state nuclear track technique, W. Arafa [2002. Permeability of radon 222 through some materials. Radiat. Meas. 35, 207-211] method and our proposed method. In addition to this, in this study, the diffusion coefficient of radon in charcoal as well as solubility of Radon in polyethylene membrane has been taken into consideration.

  19. Measurements of radon in dwellings with CR-39 track detectors

    DEFF Research Database (Denmark)

    Majborn, Benny

    1986-01-01

    A passive integrating dosemeter has been designed for measuring natural radiation in dwellings. The dosemeter contains one or two CR-39 track detectors to measure radon and three thermoluminescence dosemeters to measure external radiation. The dosemeter was investigated in a pilot study in 1983....../84, and it is now used in a nationwide survey of natural radiation in Danish dwellings. The characteristics of the dosemeter with respect to radon measurements are presented, and the radon monitoring results obtained in the pilot study are summarized...

  20. 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.

  1. Measurement protocol for radon measurements in workplaces above ground

    International Nuclear Information System (INIS)

    Mjoenes, L.; Soederman, A.-L.

    2004-01-01

    The Swedish Radiation Protection Authority, SSI, has established a measurement protocol for measurements of radon in workplaces. The result from a measurement according to the protocol can be compared to the limit for indoor radon at workplaces, 400 Bq/m 3 issued by the Swedish Work Environment Authority and also to the action level for schools, preschools and public buildings, 400 Bq/m 3 , issued by the National Board of Health and Welfare. The protocol recommends measurements to be done in two steps. The first measurement, called the preliminary measurement, will be done with an integrating measurement method over a period of at least two months. Track etch detectors or electret devices can be used. Since the preliminary measurements often overestimates the radon levels the workers are actually exposed to during working hours, a follow-up measurement has to be done if the preliminary measurement gives a result that exceeds 400 Bq/m 3 . In case there is need for an annual mean for comparison to the action level for schools a long-term measurement has to be done. Otherwise a method for follow-up measurements can be used at once. The follow-up measurement has to show the radon level during working hours. Two measurement strategies can be used depending on the function of the ventilation system. With the ventilation system running constantly, measurements can be done with track etch detectors for ten days or electret devices for five days. If the ventilation system is closed down at night electrets can be used for five days if the devise is open only during working hours or a continuous measurement device can be used for two days. Measurements have to be performed during the heating season, i.e. when the 24-hour average temperature is below +10 deg C, usually between October 1 and April 31. Most importantly the difference between interior and exterior temperatures must be big enough to allow natural draught ventilation system to activate. The result from a

  2. First measurement of radon transfer. Water - skin - blood - air

    International Nuclear Information System (INIS)

    Philipsborn, H. von; Grunewald, W.A.

    2000-01-01

    While radon is disliked in uranium mines and homes, it is used medically in radon spas for the treatment of several ailments. The transfer of radon gas from water, through skin into blood and into expiratory air was studied completely for the first time for a person resting 20-30 min in radon water. For waterborne radon concentrations of 1500±100 Bq/L, 4±1 Bq/L were measured in the blood and 2.4±0.5 kBq/m 3 (Bq/L) in the expiratory air. The results can be understood according to the principles of physiology. The nature of the experiments excluded persons other than the authors. Hence the study has been radiometric (physical), not clinical (medical). (orig.)

  3. Indoor radon measurements in dwellings of four Saudi Arabian cities

    Energy Technology Data Exchange (ETDEWEB)

    Al-Jarallah, M.I. E-mail: mibrahim@kfupm.edu.sa; Fazal-ur-Rehman; Abu-Jarad, F.; Al-Shukri, A

    2003-06-01

    An indoor radon survey of a total of 269 dwellings, with one dosimeter per house, distributed in four Saudi Arabian cities was carried out. The objective of this survey was to carry out indoor radon measurements of two cities in the Eastern Province, Khafji and Hafr Al-Batin and to compare this with two cities in the Western Province, Al-Madina and Taif. The survey provides additional information about indoor radon concentrations in Saudi Arabia. The results of the survey in these cities showed that the overall minimum, maximum and average radon concentration were 7,137 and 30 Bq m{sup -3}, respectively. The lowest average radon concentration (20 Bq m{sup -3}) was found in Hafr Al-Batin, while the highest average concentration was found in Khafji (40 Bq m{sup -3})

  4. Radon measurements in well and spring water in Lebanon

    International Nuclear Information System (INIS)

    Abdallah, Samer M.; Habib, Rima R.; Nuwayhid, Rida Y.; Chatila, Malek; Katul, Gabriel

    2007-01-01

    The variation of dissolved radon ( 222 Rn) levels in water supplies remains of interest because of the radiation-induced public health hazards. A large part of the Lebanese population relies on springs and wells for their drinking water. 222 Rn measurements in spring and well water sources were conducted using the E-PERM method at sites ranging from sea level to 1200m above sea level and across several geologic formations within Lebanon. The dissolved radon concentrations ranged from a low of 0.91BqL -1 in a coastal well source to a high of 49.6BqL -1 for a spring source in a mountainous region. Of the 20 sites sampled, only five had radon levels above 11BqL -1 and these mostly occurred in areas adjacent to well-known geological fault zones. A preliminary national average radon level was determined to be about 11.4BqL -1 . In general, as all determined concentrations were well below the 100 and 146BqL -1 revised reference levels proposed in the European Union and the United States, respectively, it is concluded that there is no reason to believe these water sources pose any radon-related hazard. On the other hand, at locations where water is collected directly from the springhead, it is advisable to have a settling/piping system installed allowing for further radon decay and radon loss into the air to alleviate any possible radon problem

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

    Science.gov (United States)

    Cauwels, P; Poffijn, A

    2000-05-01

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

  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. 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)

  8. Radon Measurement Proficiency (RMP) Program methods and devices

    International Nuclear Information System (INIS)

    Harrison, J.; Hoornbeek, J.; Jalbert, P.; Sensintaffar, E.; Hopper, R.

    1991-01-01

    The US EPA developed the voluntary Radon Measurement Proficiency Program in 1986 in response to a Federal and State need for measurement services firms to demonstrate their proficiency with radon measurement methods and devices. Since that time, the program has set basic standards for the radon measurement industry. The program has grown dramatically since its inception. In 1986, fewer than 50 companies participated in the program. By 1989, more than 5,000 companies were participating. Participants represent firms with an analytical capability as well as firms that rely upon another firm for analysis service. Since the beginning of the RMP Program, the Agency has learned a great deal about radon measurement methods and devices. This paper reviews the measurement devices used in the program and what the EPA has learned about them since the program's inception. Performance data from the RMP Program are used to highlight relevant findings

  9. Measurement of activity-weighted size distributions of radon decay products in a normally occupied home

    International Nuclear Information System (INIS)

    Hopke, P.K.; Wasiolek, P.; Montassier, N.; Cavallo, A.; Gadsby, K.; Socolow, R.

    1992-01-01

    In order to assess the exposure of individuals to the presence of indoor radioactivity arising from the decay of radon, an automated, semicontinuous graded screen array system was developed to permit the measurement of the activity-weighted size distributions of the radon progeny in homes. The system has been modified so that the electronics and sampling heads can be separated from the pump by approximately 15 m. The system was placed in the living room of a one-storey house with basement in Princeton, NJ and operated for 2 weeks while the house was occupied by the home owners in their normal manner. One of the house occupants was a cigarette smoker. Radon and potential alpha energy concentration (PAEC) measurements were also made, but condensation nuclei counts were not performed. PAEC values ranged from 23.4 to 461.6 mWL. In the measured activity size distributions, the amount of activity in the 0.5-1.5 nm size range can be considered to be the unattached fraction. The mean value for the 218 Po unattached fraction is 0.217 with a range of 0.054-0.549. The median value for the unattached fraction of PAEC is 0.077 with a range of 0.022-0.178. (author)

  10. Radon concentration measurements for determination of radiation dose and assessment of cancer risk in the premises of some colleges in Lahore, Pakistan

    International Nuclear Information System (INIS)

    Mahmood, A.; Tufail, M.; Iqbal, M.A.

    2010-01-01

    Radon concentration has been measured in campus and hostel buildings of some colleges in the city of Lahore. The technique of passive radon measurements was employed using CN-85 etched track detectors in the box type dosimeters. The observed radon concentration in different parts of monitored buildings was within the range 18-61 Bq m/sup -3/. The cause of radon in college buildings may be the construction materials, drinking water, natural gas, drainage, sewerage pipes, etc. Moving fans, open doors and windows in summer season diluted the radon concentration, while the air tight arrangement in the winter enhanced the radon concentration level. Alpha dose from radon to the students and supporting staff was estimated as 0.34 and 0.91 mSv y/sup -1/ in campus and hostel buildings respectively. The corresponding excess lifetime cancer risk attributed to the students and staff in the college campuses was found to be 0.20 %, while the staff and students residing in the hostels of the colleges received the excess lifetime risk of cancer 0.53 % due to radon progenies. (author)

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

    International Nuclear Information System (INIS)

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

    2013-01-01

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

  12. A brief overview on radon measurements in drinking water.

    Science.gov (United States)

    Jobbágy, Viktor; Altzitzoglou, Timotheos; Malo, Petya; Tanner, Vesa; Hult, Mikael

    2017-07-01

    The aim of this paper is to present information about currently used standard and routine methods for radon analysis in drinking waters. An overview is given about the current situation and the performance of different measurement methods based on literature data. The following parameters are compared and discussed: initial sample volume and sample preparation, detection systems, minimum detectable activity, counting efficiency, interferences, measurement uncertainty, sample capacity and overall turnaround time. Moreover, the parametric levels for radon in drinking water from the different legislations and directives/guidelines on radon are presented. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Radon measurement in the Architectonic Assembly of Guapulo

    International Nuclear Information System (INIS)

    Jarrin Cornejo, Andrea

    2001-01-01

    The radon is a radioactive gas that does not have color nor scent. The radon comes from the natural decomposition of uranium, an element that is in almost all the types of ground, even on the rock and the water. In general, the radon moves upwards, through the ground, until the air that you breathe. The radon-222 is considered like the second cause of the pulmonary cancer soon of the cigarette, existing greater probability of that a person acquires the greater disease whichever is the exhibition that she is put under. The radon comes from the natural decay (radioactive) of the radio-226 in the ground, rocks and water entering to any type of construction. Any construction can have a problem of radon; therefore to examine is the only way to know such risk. Of it is in favor reason, has determined the concentration of Radon-222 in the interior of the Architectonic Assembly of Guapulo. For it, the System E P ERM was used like quantification method (System Environmental Monitor of Radon) that finds the measurement from a diminution of voltage in an electrical ion camera; which, goes has to be proportional to the amount of present gas in the room. The monitoring points are the different parts from the Convent, the University, and the Church in which the predominant materials of construction are the brick, block, stone, tile, plank and marinate. Of the results, the found values average do not surpass in the Architectonic Assembly of Guapulo, the 200 Bq/m3 (maximum limit established internationally for the concentration of Radon). On the other hand, for the different materials from construction the walls of adobe have greater amount of radon to be formed almost in their totality by elements of the ground, followed those of brick, block and concrete respectively. (The author)

  14. Measurements of radon concentrations at caves in Jeju

    Energy Technology Data Exchange (ETDEWEB)

    Go, S. H.; Kang, D. H.; Jung, B. J. [Cheju National University, Cheju (Korea, Republic of)

    2004-07-01

    Radon is a radioactive gas emitting {alpha} particles. It is chemically stable due to its inert characteristic. While its daughter products, {sup 218}Po, {sup 214}Bi, {sup 214}Pb and {sup 214}Po, attached with aerosol particles, is known to cause lung cancer. As radon is produced from uranium and thorium, it accumulates in poorly ventilative underground voids such as caves and mine. Radon concentrations at caves in Jeju were measured in this study. The measurements were made by setting three CR-39 detectors for 70 days at 2 {approx} 4 positions in Manjang, Hyupjae and Ssangyong caves. The radon levels of the caves spread 403.1 . 606.7 Bq/m{sup 3}. With these results, it is concluded that the Jeju caves have 6 times higher radon concentrations than ordinary house of 65.3 Bq/m{sup 3} and that they are higher than Seoul subway stations due to poor ventilation. While, the caves in Jeju have lower radon concentrations than limestone caves of Robin Hood. The radon concentration in the middle of Manjang cave is slightly higher than the action level in the work place of 500 Bq/m{sup 3} suggested by the ICRP. The measurement errors are estimated to be less than 5 % from its calibration factor.

  15. Measurements of radon concentrations at caves in Jeju

    International Nuclear Information System (INIS)

    Go, S. H.; Kang, D. H.; Jung, B. J.

    2004-01-01

    Radon is a radioactive gas emitting α particles. It is chemically stable due to its inert characteristic. While its daughter products, 218 Po, 214 Bi, 214 Pb and 214 Po, attached with aerosol particles, is known to cause lung cancer. As radon is produced from uranium and thorium, it accumulates in poorly ventilative underground voids such as caves and mine. Radon concentrations at caves in Jeju were measured in this study. The measurements were made by setting three CR-39 detectors for 70 days at 2 ∼ 4 positions in Manjang, Hyupjae and Ssangyong caves. The radon levels of the caves spread 403.1 . 606.7 Bq/m 3 . With these results, it is concluded that the Jeju caves have 6 times higher radon concentrations than ordinary house of 65.3 Bq/m 3 and that they are higher than Seoul subway stations due to poor ventilation. While, the caves in Jeju have lower radon concentrations than limestone caves of Robin Hood. The radon concentration in the middle of Manjang cave is slightly higher than the action level in the work place of 500 Bq/m 3 suggested by the ICRP. The measurement errors are estimated to be less than 5 % from its calibration factor

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1987-12-01

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

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

    International Nuclear Information System (INIS)

    Matthews, T.G.; Dudney, C.S.; Monar, K.P.

    1987-12-01

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

  18. Indoor radon measurements in the dwellings of Kangra District of Himachal Pradesh, India, using LR-115 nuclear track detectors

    Energy Technology Data Exchange (ETDEWEB)

    Dhiman, M. [Punjab Technical University (India); Mehra, R. [Department of Physics, Dr. B.R. Ambedkar National Institute of Technology (India); Tyagi, A.K. [Department of Applied Sciences, Shaheed Bhagat Singh College of Engineering and Technology (India)

    2014-07-01

    Study of indoor radon was carried out in the domestic environment of 15 villages of Kangra district of Himachal Pradesh, India. Time integrated track etch technique has been used for the measurement of indoor radon levels. Bare cellulose nitrate LR-115 type II films have been used as detectors in the survey of indoor radon for four seasons of three months each covering a period of one year from March 2012 to March 2013. The houses were chosen randomly in such a way that the dwellings constructed with different types of building materials such as soil, bricks, cement, marble, concrete, wood in different localities of the village are covered. It has been found that indoor radon concentration depends upon the type of house, ventilation condition etc. The calibration constant of 1 track cm{sup -2} day{sup -1} which is equal to 50 Bqm{sup -3} has been used to express radon concentration in Bqm{sup -3}. The conversion factors have been used to calculate the exposure (an exposure of an individual to radon progeny of 1 WLM is equivalent to 3.54 mJ h m{sup -3}), the annual effective dose (1 WLM=3.88 mSv) and the lifetime fatality risk (3 x 10{sup -4} WLM). Indoor radon concentrations were found to vary from 132.25 Bqm{sup -3} to 449.75 Bqm{sup -3} with an average value of 261.40 Bqm{sup -3}. Annual effective dose in these dwellings were found to vary form 2.78 mSv to 7.68 mSv with an average value of 4.5 mSv. The average radon concentration in dwellings in most of the villages falls in the action level (200-600 Bqm{sup -3}) recommended by International Commission on Radiological Protection. Document available in abstract form only. (authors)

  19. National radon measurement-proficiency program: Individual proficiency report

    International Nuclear Information System (INIS)

    1992-05-01

    In February 1986, the U.S. Environmental Protection Agency (EPA) established the Radon Measurement Proficiency (RMP) Program to assist the public in identifying organizations capable of providing reliable radon measurement services. In December 1991, EPA announced the new individual proficiency listing category in the RMP Program. Individuals applying for this new listing status must demonstrate knowledge of radon measurement fundamentals by passing a written proficiency examination, maintain affiliation with an RMP listed organization, and meet other program requirements. This report lists those individuals who have met the requirements of the RMP Program as of April 30, 1992. These requirements are designed to provide minimum proficiency criteria for individuals who provide radon measurement services on-site in a residential environment

  20. Development of measure methods of radon in indoor air

    International Nuclear Information System (INIS)

    Yaginuma, L.T.; Pela, C.A.; Navas, E.A.; Ghilardi, A.J.P.

    1992-01-01

    The development of some conventional measuring methods, aiming obtain an estimation of radon concentration in air, mainly in indoor air is described, including the charcoal absorption collector, Lucas cell and thermoluminescent dosemeters. (C.G.C)

  1. Radon concentration measurements in the desert caves of Saudi Arabia

    International Nuclear Information System (INIS)

    Al-Mustafa, Hanan; Al-Jarallah, M.I.; Fazal-ur-Rehman; Abu-Jarad, F.

    2005-01-01

    Beneath the harsh deserts of Saudi Arabia lie dark chambers and complex mazes filled with strange shapes and wondrous beauty. Radon concentration measurements have been carried out in the desert caves of Al-Somman Plateau in the Eastern Province of Saudi Arabia. Passive radon dosimeters, based on alpha particle etch track detectors with an inlet filter, were used in this study. A total of 59 dosimeters were placed in five caves for a period of six months. Out of 59 dosimeters, 37 could be collected for analysis. Measurements showed significant variations in radon concentrations in caves depending upon their natural ventilation. The results of the study show that the average radon concentration in the different caves ranges from 74 up to 451Bqm -3 . The average radon concentration in four of the caves was low in the range 74-114Bqm -3 . However, one cave showed an average radon concentration of 451Bqm -3 . Radon is not a problem for tourists in the majority of caves. However, sometimes it may imply some limitation to the working time of guides

  2. Radon concentration measurements in the desert caves of Saudi Arabia

    Energy Technology Data Exchange (ETDEWEB)

    Al-Mustafa, Hanan [Women College, P. O. Box 838, Dammam 31113 (Saudi Arabia); Al-Jarallah, M.I. [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)]. E-mail: mibrahim@kfupm.edu.sa; Fazal-ur-Rehman [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Abu-Jarad, F. [Radiation Protection Unit, Environmental Protection Department, Saudi Aramco P.O. Box 13027, Dhahran 31311 (Saudi Arabia)

    2005-11-15

    Beneath the harsh deserts of Saudi Arabia lie dark chambers and complex mazes filled with strange shapes and wondrous beauty. Radon concentration measurements have been carried out in the desert caves of Al-Somman Plateau in the Eastern Province of Saudi Arabia. Passive radon dosimeters, based on alpha particle etch track detectors with an inlet filter, were used in this study. A total of 59 dosimeters were placed in five caves for a period of six months. Out of 59 dosimeters, 37 could be collected for analysis. Measurements showed significant variations in radon concentrations in caves depending upon their natural ventilation. The results of the study show that the average radon concentration in the different caves ranges from 74 up to 451Bqm{sup -3}. The average radon concentration in four of the caves was low in the range 74-114Bqm{sup -3}. However, one cave showed an average radon concentration of 451Bqm{sup -3}. Radon is not a problem for tourists in the majority of caves. However, sometimes it may imply some limitation to the working time of guides.

  3. Radon in workplaces

    International Nuclear Information System (INIS)

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

    2000-01-01

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

  4. Ground-truthing predicted indoor radon concentrations by using soil-gas radon measurements

    International Nuclear Information System (INIS)

    Reimer, G.M.

    2001-01-01

    Predicting indoor radon potential has gained in importance even as the national radon programs began to wane. A cooperative study to produce radon potential maps was conducted by the Environmental Protection Agency (EPA), U.S. Geological Survey (USGS), Department of Energy (DOE), and Lawrence Berkeley Laboratory (LBL) with the latter taking the lead role. A county-wide predictive model based dominantly on the National Uranium Resource Evaluation (NURE) aerorad data and secondly on geology, both small-scale data bases was developed. However, that model breaks down in counties of complex geology and does not provide a means to evaluate the potential of an individual home or building site. Soil-gas radon measurements on a large scale are currently shown to provide information for estimating radon potential at individual sites sort out the complex geology so that the small-scale prediction index can be validated. An example from Frederick County, Maryland indicates a positive correlation between indoor measurements and soil-gas data. The method does not rely on a single measurement, but a series that incorporate seasonal and meteorological considerations. (author)

  5. Measurement of radon activity concentrations in air of Tuzla city

    International Nuclear Information System (INIS)

    Adrovic, F.; Fazlic, R.; Tresnjo, Z.

    2004-01-01

    The survey was conducted over one year in the area of Tuzla city and its surrounding. At the measuring locations there were registered Daily and seasonal variations in outdoor radon concentration were observed, with average values lying within the region of 9 - 30 Bq/m 3 . The results of the measurements will be included in the concentration map of radon activity in Bosnia and Herzegovina, which is under preparation. (P.A.)

  6. Direct progeny detection techniques and random epidemiology

    International Nuclear Information System (INIS)

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

    2015-01-01

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

  7. 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

  8. Measurement of radon concentration in air employing Lucas chamber

    International Nuclear Information System (INIS)

    Machaj, B.

    1997-01-01

    The results of investigations aimed to determine the main features of radon concentration gauge in air, employing 0.17 L Lucas chamber, and air sample forced by an air pump are presented. For two hour sampling and measuring cycle time the dynamic error in the worst case (first read out) equals 5 % relative to the step jump of radon concentration. This is due to the increase of activity of the decay products in the chamber. It was observed that the short lived radon decay products (Po-218, Pb-214, Bi-214) are depositing on the walls of the chamber and they are not removed by flushing the chamber with air. (author)

  9. Calculating CR-39 Response to Radon in Water Using Monte Carlo Simulation

    International Nuclear Information System (INIS)

    Razaie Rayeni Nejad, M. R.

    2012-01-01

    CR-39 detectors are widely used for Radon and progeny measurement in the air. In this paper, using the Monte Carlo simulation, the possibility of using the CR-39 for direct measurement of Radon and progeny in water is investigated. Assuming the random position and angle of alpha particle emitted by Radon and progeny, alpha energy and angular spectrum that arrive at CR-39, the calibration factor, and the suitable depth of chemical etching of CR-39 in air and water was calculated. In this simulation, a range of data were obtained from SRIM2008 software. Calibration factor of CR-39 in water is calculated as 6.6 (kBq.d/m 3 )/(track/cm 2 ) that is corresponding with EPA standard level of Radon concentration in water (10-11 kBq/m 3 ). With replacing the skin instead of CR-39, the volume affected by Radon and progeny was determined to be 2.51 mm 3 for one m 2 of skin area. The annual dose conversion factor for Radon and progeny was calculated to be between 8.8-58.8 nSv/(Bq.h/m 3 ). Using the CR-39 for Radon measurement in water can be beneficial. The annual dose conversion factor for Radon and progeny was calculated to be between 8.8-58.8 nSv/ (Bq.h/m 3 ).

  10. Mathematical model of radon activity measurements

    Energy Technology Data Exchange (ETDEWEB)

    Paschuk, Sergei A.; Correa, Janine N.; Kappke, Jaqueline; Zambianchi, Pedro, E-mail: sergei@utfpr.edu.br, E-mail: janine_nicolosi@hotmail.com [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil); Denyak, Valeriy, E-mail: denyak@gmail.com [Instituto de Pesquisa Pele Pequeno Principe, Curitiba, PR (Brazil)

    2015-07-01

    Present work describes a mathematical model that quantifies the time dependent amount of {sup 222}Rn and {sup 220}Rn altogether and their activities within an ionization chamber as, for example, AlphaGUARD, which is used to measure activity concentration of Rn in soil gas. The differential equations take into account tree main processes, namely: the injection of Rn into the cavity of detector by the air pump including the effect of the traveling time Rn takes to reach the chamber; Rn release by the air exiting the chamber; and radioactive decay of Rn within the chamber. Developed code quantifies the activity of {sup 222}Rn and {sup 220}Rn isotopes separately. Following the standard methodology to measure Rn activity in soil gas, the air pump usually is turned off over a period of time in order to avoid the influx of Rn into the chamber. Since {sup 220}Rn has a short half-life time, approximately 56s, the model shows that after 7 minutes the activity concentration of this isotope is null. Consequently, the measured activity refers to {sup 222}Rn, only. Furthermore, the model also addresses the activity of {sup 220}Rn and {sup 222}Rn progeny, which being metals represent potential risk of ionization chamber contamination that could increase the background of further measurements. Some preliminary comparison of experimental data and theoretical calculations is presented. Obtained transient and steady-state solutions could be used for planning of Rn in soil gas measurements as well as for accuracy assessment of obtained results together with efficiency evaluation of chosen measurements procedure. (author)

  11. Remedial measures in Swedish and Norwegian houses - application of radon and radon decay product measurements

    International Nuclear Information System (INIS)

    Just, G.; Philipsborn, H. von; Matolin, M.; Molzahn, D.

    1998-01-01

    Houses and apartments in Sweden and Norway with excessive indoor radon concentrations were studied in detail with a variety of methods, standard and novel ones recently developed. For suitable remediation it is necessary to distinguish soil radon and exhalation from blue (porous) concrete. Our CARBOTEST-S is a simple, sensitive, in-situ method to quantify radon exhalation from existing walls, as well as radon permeability of different protective foils and final quality control of foils applied to existing walls. (orig.) [de

  12. Uncertainties of estimating average radon and radon decay product concentrations in occupied houses

    International Nuclear Information System (INIS)

    Ronca-Battista, M.; Magno, P.; Windham, S.

    1986-01-01

    Radon and radon decay product measurements made in up to 68 Butte, Montana homes over a period of 18 months were used to estimate the uncertainty in estimating long-term average radon and radon decay product concentrations from a short-term measurement. This analysis was performed in support of the development of radon and radon decay product measurement protocols by the Environmental Protection Agency (EPA). The results of six measurement methods were analyzed: continuous radon and working level monitors, radon progeny integrating sampling units, alpha-track detectors, and grab radon and radon decay product techniques. Uncertainties were found to decrease with increasing sampling time and to be smaller when measurements were conducted during the winter months. In general, radon measurements had a smaller uncertainty than radon decay product measurements. As a result of this analysis, the EPA measurements protocols specify that all measurements be made under closed-house (winter) conditions, and that sampling times of at least a 24 hour period be used when the measurement will be the basis for a decision about remedial action or long-term health risks. 13 references, 3 tables

  13. A self-calibrating radon monitor with statistical discrimination

    International Nuclear Information System (INIS)

    Valcov, N.; Purghel, L.

    2002-01-01

    A radon monitor, able to perform the measurement of the radon and its progeny volumic activity, in a gamma-ray or natural radiation background field, was developed. The instrument consists of a 10 l ionization chamber, a high voltage source, an integrating preamplifier, a data acquisition system and a personal computer. A new method for self-calibration of Radon volumic activity measurements, based on the alpha counting with an ionization chamber is also presented

  14. Reconstruction of national distribution of indoor radon concentration in Russia using results of regional indoor radon measurement programs

    International Nuclear Information System (INIS)

    Yarmoshenko, I.; Malinovsky, G.; Vasilyev, A.; Zhukovsky, M.

    2015-01-01

    The aim of the paper is a reconstruction of the national distribution and estimation of the arithmetic average indoor radon concentration in Russia using the data of official annual 4-DOZ reports. Annual 4-DOZ reports summarize results of radiation measurements in 83 regions of Russian Federation. Information on more than 400 000 indoor radon measurements includes the average indoor radon isotopes equilibrium equivalent concentration (EEC) and number of measurements by regions and by three main types of houses: wooden, one-storey non-wooden, and multi-storey non-wooden houses. To reconstruct the national distribution, all-Russian model sample was generated by integration of sub-samples created using the results of each annual regional program of indoor radon measurements in each type of buildings. According to indoor radon concentration distribution reconstruction, all-Russian average indoor radon concentration is 48 Bq/m"3. Average indoor radon concentration by region ranges from 12 to 207 Bq/m"3. The 95-th percentile of the distribution is reached at indoor radon concentration 160 Bq/m"3. - Highlights: • Reconstruction of indoor radon concentration distribution in Russia was carried out. • Data of official annual 4-DOZ reports were used. • All-Russian average indoor radon concentration is 48 Bq/m"3. • The 95-th percentile is 160 Bq/m"3.

  15. 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)

  16. Development of model DTY-104 radon measuring meter

    International Nuclear Information System (INIS)

    Shi Zhixia; Zhang Aiming; Li Yachun; Wang Qingheng

    2000-01-01

    Model DTY-104 radon measuring meter is an improvement on Model DTY-103. 'Difference value method' is used, which has been strictly developed and makes the radon exhalation rate more accurate, instead of using 'simplified difference value method'. The electronic circuit is redesigned and 80C31 single chip processor is used, which makes the operation more convenient and the function strengthened. In a more reasonable manner, the humidity sensor is mounted in the collection chamber. The collection efficiency can be automatically corrected. The technique of exchanging the collection mylar reduces the waiting time and improves work efficiency. The apparatus is applied to the measurement of the radon concentration in the environment and the radon exhalation from the surface of the building materials, walls and ground. The lower detection limit is about 4Bq/m 3 for 222 Rn concentration and 5 x 10 -5 Bq/s/m 2 for 222 Rn exhalation rate

  17. Environmental radon dosimetry in Indian dwellings and workplaces

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-07-01

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

  18. Environmental radon dosimetry in Indian dwellings and workplaces

    International Nuclear Information System (INIS)

    Kant, K.; Upadhyay, S.B.

    2006-01-01

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

  19. Establishment of a radon test chamber

    International Nuclear Information System (INIS)

    Chen Chingjiang; Liu Chichang; Lin Yuming

    1993-01-01

    A walk-in type radon test chamber of 23 m 3 has been built for testing and calibration of radon measurement instruments. The environmental conditions of the test chamber can be varied within a wide range of values. The design objectives specification, monitoring instruments and testing results of this chamber are discussed. This test chamber is available for domestic radon researchers and its accuracy can be traced to the international standard. A routine intercomparison study will be held annually by using this chamber. Other tests like radon progeny and thoron standard may also be performed in this chamber. (1 fig.)

  20. Wire-mesh capped deposition sensors: Novel passive tool for coarse fraction flux estimation of radon thoron progeny in indoor environments

    International Nuclear Information System (INIS)

    Mayya, Y.S.; Mishra, Rosaline; Prajith, Rama; Sapra, B.K.; Kushwaha, H.S.

    2010-01-01

    Deposition-based 222 Rn and 220 Rn progeny sensors act as unique, passive tools for determining the long time-averaged progeny deposition fluxes in the environment. The use of these deposition sensors as progeny concentration monitors was demonstrated in typical indoor environments as conceptually superior alternatives to gas-based indirect monitoring methods. In the present work, the dependency of these deposition monitors on various environmental parameters is minimized by capping the deposition sensor with a suitable wire mesh. These wire-mesh capped deposition sensors measure the coarse fraction deposition flux, which is less dependent on the change in environmental parameters like ventilation rate and turbulence. The calibration of these wire-mesh capped coarse fraction progeny sensors was carried out by laboratory controlled experiments. These sensors were deployed both in indoor and in occupational environments having widely different ventilation rates. The obtained coarse fraction deposition velocities were fairly constant in these environments, which further confirmed that the signal on the wire-mesh capped sensors show the least dependency on the change in environmental parameters. This technique has the potential to serve as a passive particle sizer in the general context of nanoparticles using progeny species as surrogates. On the whole, there exists a strong case for developing a passive system that responds only to coarse fraction for providing alternative tools for dosimetry and environmental fine particle research. - Research highlights: → Wire-mesh capped deposition sensor measures the coarse fraction deposition flux → Coarse fraction deposition flux less dependent on environmental conditions → Wire-mesh capped deposition sensor as passive particle sizer

  1. Radon measurements by track detectors in Calabrian workplaces

    Energy Technology Data Exchange (ETDEWEB)

    Nastro, V.; Niceforo, G.; Vuono, D.; Luca, P. de; Nastro, A. [Calabria Univ., Dipt. di Pianificazione Territoriale, Arcavacata di Rende, CS (Italy)

    2006-07-01

    Indoor radon studies have been carried out in some workplaces of the South Calabria (Italy) by track detectors CR-39. This study has been undertaken for the purpose of safeguarding the public healthy: since the European population spends, in average, the most greater part of their time in confined environments(residences and offices) the risks of exposure can be elevated. This radon passive measurements are been effectuated according to the recommendations. The exposure time in the workplaces was two different cycle: three months, and six months. The obtained results indicate a radon concentration not only in an average of low level but also in the range of action level (>500 Bq/m{sup 3}). In this last case will be necessary to reduce the radon pollution by adequate land operation works, and a continuous monitoring is also necessary.

  2. Can radon gas measurements be used to predict earthquakes?

    International Nuclear Information System (INIS)

    2009-01-01

    After the tragic earthquake of April 6, 2009 in Aquila (Abruzzo), a debate has begun in Italy regarding the alleged prediction of this earthquake by a scientist working in the Gran Sasso National Laboratory, based on radon content measurements. Radon is a radioactive gas originating from the decay of natural radioactive elements present in the soil. IRSN specialists are actively involved in ongoing research projects on the impact of mechanical stresses on radon emissions from underground structures, and some of their results dating from several years ago are being brought up in this debate. These specialists are therefore currently presenting their perspective on the relationships between radon emissions and seismic activity, based on publications on the subject. (authors)

  3. 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)

  4. Radon measurements by track detectors in Calabrian workplaces

    International Nuclear Information System (INIS)

    Nastro, V.; Niceforo, G.; Vuono, D.; Luca, P. de; Nastro, A.

    2006-01-01

    Indoor radon studies have been carried out in some workplaces of the South Calabria (Italy) by track detectors CR-39. This study has been undertaken for the purpose of safeguarding the public healthy: since the European population spends, in average, the most greater part of their time in confined environments(residences and offices) the risks of exposure can be elevated. This radon passive measurements are been effectuated according to the recommendations. The exposure time in the workplaces was two different cycle: three months, and six months. The obtained results indicate a radon concentration not only in an average of low level but also in the range of action level (>500 Bq/m 3 ). In this last case will be necessary to reduce the radon pollution by adequate land operation works, and a continuous monitoring is also necessary

  5. Determination of groundwater flow velocity by radon measurements

    International Nuclear Information System (INIS)

    Hohn, E.; von Gunten, H.R.

    1990-01-01

    The groundwater resources of glacio-fluvial perialpine valleys are recharged significantly by the infiltration from rivers. The groundwater residence times between rivers and wells should be known in groundwater management problems. Short residence times can be estimated using radon. Radon concentrations in rivers are usually very low. Upon filtration and movement of the water in the ground, radon is picked up and its concentration increases by 2-3 orders of magnitude according to radioactive growth laws. Residence times and flow velocities can be estimated from the increasing radon concentrations measured in groundwater sampling tubes at different distances from the river. Results obtained with this method agree with the results from experiments with artificial tracers

  6. Turbidimetry for measurement of radon concentration

    International Nuclear Information System (INIS)

    Wang Huanqiang

    1993-01-01

    This paper describes a turbidimetric technique counting the tracks registered on CR-39 foils exposed to radon. Instead of eyeview through microscope, by using the differential spectrophotometer, strong correlation between the radon cumulative concentration and track turbidence was observed(r=0.999). Under the etching condition of 7.07 mol·L -1 KOH water solution at 80 o C for 16 hr, linear regression showed that the ratio of track turbidence and cumulative concentration of radon exposure was 1.99 x 10 -1 turbidence (KBq m -1 h) -1 and the determination limit was 36 KBq m -3 h. The details of the experiments are represented in this paper. (Author)

  7. 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.)

  8. Radon in an underground cave system in Victoria

    International Nuclear Information System (INIS)

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

    1998-01-01

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

  9. Long term and equilibrium factor indoor radon measurements

    International Nuclear Information System (INIS)

    Martinez, T.; Lartigue, J.; Navarrete, M.; Cabrera, L.; Ramirez, A.; Elizarraras, V.

    1998-01-01

    This paper presents the annual radon gas concentrations obtained during the 1994-1995 monitoring campaign using passive electret system (type E-PERM). Radon levels were measured in 154 single family dwellings, in normal occupancy conditions (open house condition) in the metropolitan zone of Mexico City. At the same time radon monitoring was performed outdoors. The results show the general log-normal distribution of integrated indoor radon concentration with an annual indoor mean of 3.8 pCi x l -1 . The seasonal variations show the minimum mean values in the summer season which are 39% lower than that in autumn. Equilibrium factors (F) were measured in 12 typical houses both in autumn and winter using a continuous working level monitor for short-lived radon decay products and H-chamber loaded with a short term electret (HST, E-PERM) for radon gas. The obtained total mean equilibrium factors are: F=0.41±0.17 and F=0.29±0.04 for indoor and outdoor, respectively. A quality program was also improved. (author)

  10. Towards the use of small amounts of activated charcoal along with well-type NaI(Tl) detector for indoor radon measurements

    International Nuclear Information System (INIS)

    Al-Azmi, D.

    2006-01-01

    The feasibility of using small quantities of activated charcoal and a 7.6 cm x 7.6 cm NaI(Tl) well-type detector was investigated for indoor radon measurements. Vials, filled with 10 g of charcoal, were exposed for different indoor radon concentration levels typical of Kuwait dwellings. After exposure, the vials were sealed and kept for 3 h to allow radon to come into radioactive equilibrium with its progenies and were then analysed by gamma-ray spectrometry using the well-type NaI(Tl) detector. The variation of radon absorption by the vials filled with charcoal with exposure time was also studied. A comparative study of the present technique with the standard technique of using 70 g charcoal canisters and flat NaI detector was also performed. After establishing the suitability of the technique, the charcoal vials were then used to investigate the effect of air-ventilation on the concentration levels of the indoor radon. Results show that there is a reduction in the radon concentration level (up to 25%) when the air-ventilation system was switched on. The paper presents the results of the study on the feasibility of combining small amounts of activated charcoal with a well-type NaI(Tl) detector in the measurement of indoor radon concentrations. (authors)

  11. Studying the response of CR-39 to radon in non-polar liquids above water by Monte Carlo simulation and measurement

    International Nuclear Information System (INIS)

    Rezaie, Mohammad Reza; Sohrabi, Mehdi; Negarestani, Ali

    2013-01-01

    The application of CR-39 has been extensive for measurement of radon and progeny in air of dwellings, but limited as regards to measurements of radon in water. In this paper, a new method is introduced for efficient measurement of radon in water by registering alpha particle tracks in a CR-39 detector placed in a non-polar medium such as cyclohexane, hexane and olive oil when each mixed with water, then separated and fixed above water, as a two-phase media. The method introduced here is however different from the widely used liquid - liquid extraction technique by liquid scintillation spectrometry since it is a passive detection method (CR-39) in a non-polar liquid with enhanced absorption of radon in the liquid, it has a capability for long sample counting to decrease the minimum detection limit (MDL), it does not require sophisticated low light counting systems, and it has the potential for simultaneous measurements of large number of samples for large-scale applications. It also has a low cost and is readily available. A new Monte Carlo calculation of energy-distance travelled by alphas from radon and progeny in a medium was also investigated. The sensitivity of CR-39 detector to radon and progeny in water was determined under two conditions; in a single-phase and two-phase media. In a single-phase medium, CR-39 is directly placed either in air, water, cyclohexane, hexane or olive oil. When CR-39 is placed directly in water, its sensitivity is (2.4 ± 0.1) × 10 −4 (track/cm 2 )/(Bq.d/m 3 ). In the two-phase media, CR-39 is placed either in cyclohexane, hexane or olive oil when each is fixed above water. The sensitivities in the two-phase media are significantly enhanced and are respectively (1.98 ± 0.10) × 10 −2 , (2.8 ± 0.15) × 10 −2 and (2.86 ± 0.15) × 10 −2 (track/cm 2 )/(Bq.d/m 3 ). The sensitivies are about 76, 82 and 110 times more than that of when CR-39 is directly placed in water. The new method is a novel alternative for radon

  12. Radon as a geophysical tracer on Mars: study of its transport, first evidence and development of an instrument for its measurement

    International Nuclear Information System (INIS)

    Meslin, Pierre-Yves

    2008-01-01

    Radon-222, an inert and radioactive gas stemming from the uranium decay series, and its progeny are often used as tracers to study transfers in soils and in the atmosphere. They have also been studied on the surface of the Moon in connection with lunar outgassing. On Mars, where radon has never been studied nor measured so far, we show that their measurement could provide new insight and constraints on the chemical nature of the hydrogen measured in the Martian soil, in surface-atmosphere exchange processes, in atmospheric transport and, finally, in the dust cycle. Our approach is based on a coupled soil-atmosphere transport model implemented into the Global Circulation Model LMDZ. It includes the source term, the diffusion and adsorption of radon within the soil, and its atmospheric transport. The model input parameters are derived either experimentally (emanation factor and adsorption coefficient extrapolated to low temperatures) or by realistic models of porous media (diffusion coefficient at low pressure and as a function of the water saturation level). The model yields predictive maps of the radon exhalation rate as well as 3D fields of concentration in the soil and atmosphere, which will allow direct comparison with bismuth-214 measurements made by the GRS onboard the Mars Odyssey orbiter. We present preliminary results on this subject. An analysis of alpha spectra acquired by the APXS of the rover Opportunity is also presented, which shows evidence of a polonium-210 deposit on atmospheric dust, providing the first indirect proof of the presence of radon in the Martian atmosphere. We propose a simplified dust cycle model that enables us to infer an estimate of the global average radon exhalation rate on Mars. Lastly, we simulate the performance of an alpha spectrometer aimed at measuring radon and its progeny on the surface of the planet. (author)

  13. A nationwide survey of radon concentration in Japan. Indoor, outdoor and workplace

    International Nuclear Information System (INIS)

    Sanada, Tetsuya; Oikawa, Shinji; Kanno, Nobuyuki; Abukawa, Johji; Higuchi, Hideo

    2004-01-01

    The nationwide indoor, outdoor and workplace radon concentrations were surveyed in Japan. These surveys were conducted to estimate the natural radiation dose due to radon and its progeny for the general public. The radon concentration was measured using passive type radon monitor. The number of radon monitors were installed at indoor, outdoor and workplace for 940 houses, 705 points and 705 sites, respectively. The radon concentration was measured for one year at each measurement site. Annual mean radon concentration was obtained from four quarters measurements of 47 prefectures in Japan. The nationwide indoor, outdoor and workplace annual mean radon concentration were 15.5 Bq m -3 , 6.1 Bq m -3 and 20.8 Bq m -3 , respectively. Their radon concentration shows approximately a logarithmic normal distribution. Workplace showed relatively high radon concentration compared with other environments, may be due to construction materials and low ventilation rate. The indoor radon concentration found to be seasonal variation and architectural dependences. Seasonal variation and regional distribution of outdoor radon concentration was also observed. From the results of these radon surveys, the annual effective dose to the general public due to radon and its progeny was estimated to be 0.49 mSv y -1 in Japan. (author)

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

    International Nuclear Information System (INIS)

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

    1994-01-01

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

  15. Measurement of indoor and outdoor radon concentrations during Superstorm Sandy.

    Science.gov (United States)

    Kotrappa, Payasada; Paul, Prateek; Stieff, Alex; Stieff, Frederick

    2013-12-01

    Superstorm Sandy affected much of the US East Coast extending over 1800 km. It passed over the test location in the State of Maryland on 29 October 2012. Being 350 km away from the regions of highest intensity the storm was of lower intensity at the test location. Continuous radon monitors and passive radon monitors were used for the measurement. The test location was the basement of a single family home representing the indoor concentration. A partially opened garage of the same test home represented the outdoor radon concentration. In 24 h, the atmospheric pressure dropped from 990 to 960 mbar and the indoor radon concentration increased from 70 to 1500 Bq m(-3) and returned to the normal of 70 Bq m(-3) at the end of the storm. Throughout the storm, the outdoor radon concentration was not significantly affected. Probable reasons for such surprisingly large changes are discussed. However, the outdoor temperature dropped from 13°C to 7°C during the radon peak.

  16. Error in measuring radon in soil gas by means of passive detectors

    International Nuclear Information System (INIS)

    Tanner, A.B.

    1991-01-01

    Passive detection of radon isotopes depends on diffusion of radon atoms from the sites of their generation to the location of the detecting or collecting device. Because some radon decays en route to a passive detector in soil, the radon concentration measured by the detector must be less than the concentration in those soil pores where it is undiminished by diffusion to the detector cavity. The true radon concentration may be significantly underestimated in moist soils. (author)

  17. 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

  18. The 2010 calibration campaign for radon gas measuring instruments at PSI

    International Nuclear Information System (INIS)

    Butterweck, G.; Schuler, Ch.; Mayer, S.

    2011-01-01

    Twenty radon measurement services or the respective analytical laboratories participated in the 2010 Radon Intercomparison Exercise performed at the Reference Laboratory for Radon Gas Activity Concentration Measurements at the Paul Scherrer Institute (PSI) from August 27 th to August 31 st , 2010 on behalf of the Swiss Federal Office of Public Health (FOPH). Twelve of these laboratories were approved by the FOPH and their participation in the intercomparison exercise was a requirement to warrant quality of measurement. Radon gas dosemeters (track-etch, electronic and electret) and instruments (ionisation chambers) were exposed in the PSI Radon Chamber in a reference atmosphere with an average radon gas concentration of 595 Bq m -3 leading to a radon gas exposure of 57 kBq h m -3 . The exposure of 57 kBq h m -3 was close to the lower value of the measuring range defined in the Radon Measurement Ordinance ('Radon-Messmittelverordnung'). (authors)

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

    International Nuclear Information System (INIS)

    Lopez, Fabio O.; Canoba, Analia C.

    2001-01-01

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

  20. Hourly indoor radon measurements in a research house.

    Science.gov (United States)

    Sesana, Lucia; Begnini, Stefania

    2004-01-01

    This paper reports and discusses the behaviour of radon concentration with time in an uninhabited dwelling. The relationship between variations in radon concentrations and indoor-outdoor temperatures and wind intensity has also been discussed. Radon concentration was measured hourly in a house located at a height of 800 m in the Lombard Prealps, at the top of the Valassina valley. The wind velocity and indoor-outdoor temperatures were measured by means of a meteorological station located on the terrace of the house. The data were analysed using the LBL model for indoor-outdoor air exchange and the models for the indoor accumulation of radon due to exhalation from building materials and pressure-driven infiltrations located underground. The role of wind and indoor-outdoor temperatures were analysed. The agreement of measurements with modelling clearly demonstrates the importance of the different sources of indoor radon. As the investigation was conducted in an uninhabited house, the measurements were not affected by the behaviour of people, e.g. opening and closing of windows. Measurements of the outdoor atmospheric concentrations of (222)Rn provide an index of the atmospheric stability, the formation of thermal inversions and convective turbulence.

  1. Hourly indoor radon measurements in a research house

    International Nuclear Information System (INIS)

    Sesana, L.; Begnini, S.

    2004-01-01

    This paper reports and discusses the behaviour of radon concentration with time in an uninhabited dwelling. The relationship between variations in radon concentrations and indoor-outdoor temperatures and wind intensity has also been discussed. Radon concentration was measured hourly in a house located at a height of 800 m in the Lombard Pre-alps, at the top of the Valassina valley. The wind velocity and indoor-outdoor temperatures were measured by means of a meteorological station located on the terrace of the house. The data were analysed using the LBL model for indoor-outdoor air exchange and the models for the indoor accumulation of radon due to exhalation from building materials and pressure-driven infiltrations located underground. The role of wind and indoor-outdoor temperatures were analysed. The agreement of measurements with modelling clearly demonstrates the importance of the different sources of indoor radon. As the investigation was conducted in an uninhabited house, the measurements were not affected by the behaviour of people, e.g. opening and closing of windows. Measurements of the outdoor atmospheric concentrations of 222 Rn provide an index of the atmospheric stability, the formation of thermal inversions and convective turbulence. (authors)

  2. Measurement of radon concentration in water with Lucas cell detector

    International Nuclear Information System (INIS)

    Machaj, B.; Pienkos, J.P.

    2003-01-01

    A method for the measurement of radon concentration in water is presented based on flushing a water sample with air in a closed loop with the Lucas cell as alpha radiation detector. The main feature of the method is washing radon away from the larger sample of water (0.75 l) to a small volume of air, approximately 0.5 l, thanks to which a high radon concentration in air and a considerable sensitivity of measurement is achieved. Basic relations and results of measurements of a model of a gauge is given. The estimated measuring sensitivity (S) is 8.5 (cpm)/(Bq/l). The random error due to the statistical fluctuations of count rate at radon concentrations 1,10, 100, 1000, 10000 Bq/l is 11, 3.6, 1.1, 0.4, 0.1% correspondingly at a counting (measuring) time of 10 min. The minimum detectable radon concentration in water is 0.11 Bq/l. (author)

  3. 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.

  4. 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

  5. Radon Measurements in underground metro stations in Cairo City, Egypt

    International Nuclear Information System (INIS)

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

    2000-01-01

    Radon activity concentration were measured continuously during the year 1998-1999 at two different underground MERTO stations, namely, Mubarak and El-Sadat. The measurements were performed using the diffusion cups equipped with CR-39 and LR-115 polymeric nuclear track detectors. Using the experimentally measured calibration coefficients of the used detectors and the measured track densities (bare and filtered), the yearly mean radon concentration C=23 Bq m -3 , equilibrium factor F= 0,10 and effective dose E=0,06 mSv y -1 for the employed personal as well as E=5 mu Sv y -1 for the commuter were obtained

  6. Calibration of SSNDT detectors for radon measurements; Calibração de detectores SSNDT para medição de radônio

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Laura C.; Santos, Talita O.; Pinheiro, Rose Mary M.; Rocha, Zildete, E-mail: lauratakahashi@hotmail.com, E-mail: talitaolsantos@yahoo.com.br, E-mail: rosepin@cdtn.br, E-mail: rochaz@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-01

    The methods and instrumentation used to measure the concentration of radon need to be calibrated to obtain accurate results. The Nuclear Track Detector is considered the main method of analysis of radon research. Thus, the Natural Radioactivity Laboratory of the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG, Brazil) uses the detector CR-39 (Landauer) to measure the concentration of radon in homes, workplaces, underground mines, soils and in environment. Epidemiological studies reveal the strong relationship between lung cancer and radon exposure. Therefore, it is important to monitor this gas and its progeny in order to assess the radiological risk. The alpha particles emitted by radon and its progeny leave traces on CR-39 due to Coulombian interactions with the atoms of the material. The liquid density of traces is converted to radon concentration by means of a calibration factor obtained in calibrated systems. This work aims to determine the LRN / CDTN calibration factor. To do so, the CR-39 detectors were placed inside the calibration chambers, along with two AlphaGUARD (Saphymo GmbH) detectors and Ra-266 sources with activities of 3,379 kBq or 0.483 kBq, referenced by NIST. From this, six levels of exposure were obtained, which were: 44 kBq.d.m{sup 3}, 4 kBq.d.m{sup 3}, 3 kBq.d.m{sup 3}, 15 kBq.d.m{sup 3}, 30 kBq.d.m{sup 3} , 26 kBq.d.m {sup 3}. The conversion factor between the liquid density of traces and the total exposure time obtained was K = 52.028 ± 0.752 [(trace density.cm{sup -2}) / (kBq.d.m{sup -3})]. After the determination of the conversion factor, it was used to measure the concentration of radon in underground mines, obtaining concentration results between 122 ± 24 and 7384 ± 517 kBq.m{sup -3}.

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

    International Nuclear Information System (INIS)

    Alberigi, Simone

    2011-01-01

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

  8. 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

  9. Comparison of predicted and measured variations of indoor radon concentration

    International Nuclear Information System (INIS)

    Arvela, H.; Voutilainen, A.; Maekelaeinen, I.; Castren, O.; Winqvist, K.

    1988-01-01

    Prediction of the variations of indoor radon concentration were calculated using a model relating indoor radon concentration to radon entry rate, air infiltration and meteorological factors. These calculated variations have been compared with seasonal variations of 33 houses during 1-4 years, with winter-summer concentration ratios of 300 houses and the measured diurnal variation. In houses with a slab in ground contact the measured seasonal variations are quite often in agreement with variations predicted for nearly pure pressure difference driven flow. The contribution of a diffusion source is significant in houses with large porous concrete walls against the ground. Air flow due to seasonally variable thermal convection within eskers strongly affects the seasonal variations within houses located thereon. Measured and predicted winter-summer concentration ratios demonstrate that, on average, the ratio is a function of radon concentration. The ratio increases with increasing winter concentration. According to the model the diurnal maximum caused by a pressure difference driven flow occurs in the morning, a finding which is in agreement with the measurements. The model presented can be used for differentiating between factors affecting radon entry into houses. (author)

  10. Relationship between short and long term radon measurements

    International Nuclear Information System (INIS)

    Martinez, T.; Ramirez, D.; Navarrete, M.; Cabrera, L.; Ramirez, A.; Gonzalez, P.

    2000-01-01

    In this work the radon group of the Faculty of Chemistry at the National University of Mexico presents the results obtained in the establishment of a relation between the short and long term radon measures made with passive electret detectors E-PERM type LLT and HST. The measures were carried out inside single family dwellings (open house condition) located in the southeast of Mexico City (in Xochimilco) during the four seasons of the year 1997. A correlation was established between the short term measures (five days) and those of a long term for every season as well as an annual average, with an equation that relates them. The objective and advantage of this correlation are that with a short term measure it is possible to predict the annual mean radon concentration, that represents a saving of human and economic resources. (author)

  11. 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

  12. Developments of quad channel pulse height analyzer for radon/thoron measurement

    International Nuclear Information System (INIS)

    Ashokkumar, P.; Raman, Anand; Babu, D.A.R.; Sharma, D.N.; Topkar, Anita; Mayya, Y.S.

    2011-01-01

    Radon and thoron are naturally occurring noble radioactive gases, the exposure to which has a linear relationship to lung cancer risk. This paper describes development of an automated Radon/Thoron measurement system using an indigenously developed silicon PIN diode. This system employs the 8051 core architecture based Si-lab microcontroller (C-8051F340) integrated with LCD display, hex key pad, non volatile flash memory besides I/O ports interfaced with humidity-temperature sensors and air sampling pump. Air is sampled through a dehumidifier by using a software controlled dc pump. The positively charged progeny atoms are electro statically collected over the detector surface and the deposited radioactivity is assessed by alpha pulse height discrimination technique. The ionization charges produced due to the interaction of alpha particles in the charge depletion region of the diode which is reverse biased at 40V are collected and measured. The measurement circuit uses a charge sensitive preamplifier developed around a low noise opamp IC. The pulses are further processed through a spectroscopy amplifier to obtain distinct pulse height levels for four of the alpha emitting progenies of Rn and Tn namely 210 Po, 214 Po, 216 Po and 212 Po. These signals are input to the quad channel analyzer which provides four individual TTL pulses corresponding to four nuclides mentioned above. The analyzer outputs are processed by the microcontroller module to obtain the Rn/Tn concentration in Bq/M 3 . This portable system stores one week hourly individual channel data along with the corresponding Rn/Tn concentrations, temperature, humidity and can be transferred to pc. Preliminary studies have indicated that sensitivity as low as 0.50 cph/Bq.m -3 can be achieved by this system. (author)

  13. Radon studies in selected workplaces

    International Nuclear Information System (INIS)

    Randle, M.W.

    2000-01-01

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

  14. 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

  15. Radon concentration measurements in therapeutic spring water

    International Nuclear Information System (INIS)

    Deak, N.; Horvath, A.; Sajo B, L.; Marx, G.

    1996-01-01

    It is believed that people undergoing a curative cycle in a given spa, may receive a dose in the range of 400 mSv/year which is many times the average annual dose so that their risk of lung cancer may increase by 3% or more. To determine the risk due to the natural radioactivity, of the most frequented spas in Budapest (H), we selected four and some others located on the country side being of particular interest. Results of the radon concentration in spring water are presented, with the evidence that some spas have a high radon concentration. We conclude that patients receiving treatment may be exposed to an additional dose in the range of 29-76 mSv/year that at the bronchia could be between 445-1182 mSv/year. (authors). 6 refs., 2 figs., 2 tabs

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

    International Nuclear Information System (INIS)

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

    2012-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-07-01

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

  19. 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

  20. Measurement of average radon gas concentration at workplaces

    International Nuclear Information System (INIS)

    Kavasi, N.; Somlai, J.; Kovacs, T.; Gorjanacz, Z.; Nemeth, Cs.; Szabo, T.; Varhegyi, A.; Hakl, J.

    2003-01-01

    In this paper results of measurement of average radon gas concentration at workplaces (the schools and kindergartens and the ventilated workplaces) are presented. t can be stated that the one month long measurements means very high variation (as it is obvious in the cases of the hospital cave and the uranium tailing pond). Consequently, in workplaces where the expectable changes of radon concentration considerable with the seasons should be measure for 12 months long. If it is not possible, the chosen six months period should contain summer and winter months as well. The average radon concentration during working hours can be differ considerable from the average of the whole time in the cases of frequent opening the doors and windows or using artificial ventilation. (authors)

  1. Measurement of Radon-Induced Backgrounds in the NEXT Double Beta Decay Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Novella, P.; et al.

    2018-04-02

    The measurement of the internal 222Rn activity in the NEXT-White detector during the so-called Run-II period with 136Xe-depleted xenon is discussed in detail, together with its implications for double beta decay searches in NEXT. The activity is measured through the alpha production rate induced in the fiducial volume by 222Rn and its alpha-emitting progeny. The specific activity is measured to be $(37.5\\pm 2.3~\\mathrm{(stat.)}\\pm 5.9~\\mathrm{(syst.)})$~mBq/m$^3$. Radon-induced electrons have also been characterized from the decay of the 214Bi daughter ions plating out on the cathode of the time projection chamber. From our studies, we conclude that radon-induced backgrounds are sufficiently low to enable a successful NEXT-100 physics program, as the projected rate contribution should not exceed 0.2~counts/yr in the neutrinoless double beta decay sample.

  2. Mitigation of the effective dose of radon decay products through the use of an air cleaner in a dwelling in Okinawa, Japan

    International Nuclear Information System (INIS)

    Kranrod, Chutima; Tokonami, Shinji; Ishikawa, Tetsuo; Sorimachi, Atsuyuki; Janik, Miroslaw; Shingaki, Reina; Furukawa, Masahide; Chanyotha, Supitcha; Chankow, Nares

    2009-01-01

    Field measurements were conducted to assess the effects of an air cleaner on radon mitigation in a dwelling with a high radon concentration in Okinawa, Japan. The measurements included indoor radon concentration, individual radon progeny concentration, equilibrium equivalent concentration of radon (EECRn), unattached fraction, and size distribution of aerosol-attached radon progeny. These measurements were conducted in a 74 m 3 room with/without the use of an air cleaner. The results showed that the mean radon concentration during the measurement was quite high (301 Bq m -3 ). The operation of air cleaner decreased the radon progeny activity concentration, EECRn and equilibrium factor by 33%, 57% and 71%, respectively, whereas the unattached fraction increased by 174%. In addition, the activity concentration of attached radon progeny in the accumulation mode (50-2000 nm) was obviously deceased by 42%, when the air cleaner was operated. According to dosimetric calculations, the operation of air cleaner reduced the effective dose due to radon progeny by about 50%.

  3. Radon determination by activated charcoal adsorption and liquid scintillation measurement

    International Nuclear Information System (INIS)

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

    1998-01-01

    A passive diffusion method for the determination of radon concentration has been optimised and calibrated. The device consists of a scintillation vial containing activated charcoal, a diffusion barrier and a desiccant agent. The response to diverse atmospheric humidity and variable exposure intervals was studied. The result is a detector, which is independent of atmospheric humidity for at least (up to) 7 days of exposure. The method was compared with electret detectors (US EPA) with very satisfactory results. The advantages of this method are its simplicity, low cost, low detection limit, the total automatization of the measurement and its total independence of humidity to measure in a wide range of radon concentrations. (author) [es

  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. Indoor radon measurements in dwellings and workplaces of Curitiba urban area, Parana state, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Del Claro, Flavia; Paschuk, Sergei A.; Correa, Janine N.; Kappke, Jaqueline; Perna, Allan F.N.; Schelin, Hugo R., E-mail: sergei@utfpr.edu.br [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil); Rocha, Zildete; Santos, Talita O., E-mail: rochaz@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-07-01

    Considering that radon and its progeny exposure is proved to be the main cause of lung cancer among nonsmokers and occupation-time at some commercial establishments and workplaces is equal or even bigger then at domiciles and dwelling, present study has been spread to the constructed closed environment and workplaces of commerce and productive sector. The measurements were performed by the Laboratory of Applied Nuclear Physics of UTFPR in 2009 - 2011 when 120 detectors were installed at domiciles and workplaces of Curitiba, Parana St., Brazil. Experimental setup was based at CR-39 detectors that were installed in diffusion chambers protected with filters. In collaboration with CDTN/CNEN it was performed the calibration of CR-39 detectors at the NIRS in Japan. The exposure time was set to be of 100 days. Alpha particle track development was performed using 6.25M sodium hydroxide (NaOH) solution and ethanol (2%) during 14 hours at 70 deg C. The counting was conducted using an optical microscope. Measured {sup 222}Rn activity levels in dwellings varied between 4.37 Bq/m{sup 3} and 320.82 Bq/m{sup 3} resulting at an average of 46.94 Bq/m{sup 3}. Indoor measurements at workplaces presented the variation of radon activity concentration between 3.08 Bq/m{sup 3} and 67.50 Bq/m{sup 3} resulting at the average of 34.51 Bq/m{sup 3}. Considering the recommendations of the World Health Organization, UNSCEAR and the International Commission on Radiological Protection (ICRP) concerning the radon-in-air concentration inside the dwellings that can reach 200 Bq/m{sup 3} taking into account the occupation-time of 7000 hours/year, obtained results are within normal limits and no mitigation measures have to be performed. (author)

  6. Indoor radon measurements in dwellings and workplaces of Curitiba urban area, Parana state, Brazil

    International Nuclear Information System (INIS)

    Del Claro, Flavia; Paschuk, Sergei A.; Correa, Janine N.; Kappke, Jaqueline; Perna, Allan F.N.; Schelin, Hugo R.; Rocha, Zildete; Santos, Talita O.

    2011-01-01

    Considering that radon and its progeny exposure is proved to be the main cause of lung cancer among nonsmokers and occupation-time at some commercial establishments and workplaces is equal or even bigger then at domiciles and dwelling, present study has been spread to the constructed closed environment and workplaces of commerce and productive sector. The measurements were performed by the Laboratory of Applied Nuclear Physics of UTFPR in 2009 - 2011 when 120 detectors were installed at domiciles and workplaces of Curitiba, Parana St., Brazil. Experimental setup was based at CR-39 detectors that were installed in diffusion chambers protected with filters. In collaboration with CDTN/CNEN it was performed the calibration of CR-39 detectors at the NIRS in Japan. The exposure time was set to be of 100 days. Alpha particle track development was performed using 6.25M sodium hydroxide (NaOH) solution and ethanol (2%) during 14 hours at 70 deg C. The counting was conducted using an optical microscope. Measured 222 Rn activity levels in dwellings varied between 4.37 Bq/m 3 and 320.82 Bq/m 3 resulting at an average of 46.94 Bq/m 3 . Indoor measurements at workplaces presented the variation of radon activity concentration between 3.08 Bq/m 3 and 67.50 Bq/m 3 resulting at the average of 34.51 Bq/m 3 . Considering the recommendations of the World Health Organization, UNSCEAR and the International Commission on Radiological Protection (ICRP) concerning the radon-in-air concentration inside the dwellings that can reach 200 Bq/m 3 taking into account the occupation-time of 7000 hours/year, obtained results are within normal limits and no mitigation measures have to be performed. (author)

  7. A condensed water method for measuring the atmospheric radon

    CERN Document Server

    Wu Xin; Pan Xiao Qing; Yu Yi Ling

    1998-01-01

    The author summarizes the present situation of atmospheric Radon measurement, and introduces the working principle, working method and advantage and disadvantage of condensed water method in detail. The structure and function of the instrument used for this method, and the measuring result are discussed. The direction of further work is pointed out from now on

  8. Radon and thoron measurements at special underground circumstances

    International Nuclear Information System (INIS)

    Kovacs, Tibor; Somlai, Janos; Szeiler, Gabor; Nemeth, Csaba; Tokonami, Shinji; Takahashi, Hiroyuki

    2008-01-01

    In this study a comparative integrating radon ( 222 Rn) and thoron ( 220 Rn) survey executed at underground workplaces are discussed. Two types of solid state nuclear track detectors (Radopot and Raduet) were applied for survey at four sites: a manganese mine, a bauxite mine, a tourist cave and a hospital cave. Several numbers of detecting points were chosen at each site and 1-1 Raduet and Radopot detector were placed at each point. Both detector types contains two polycarbonate (CR-39) foils in different holders in order to determinate the radon as well as the thoron levels. The detectors were changed in 30-60 days periods (approximately monthly) and the survey continued for a year. This study had two aims: 1) To gain information about the radon and thoron concentrations at the chosen places including the seasonal variations; 2) To compare the performance of the two types of detectors and check their response in the special circumstances indicates by these underground places. Concerning the first point the radon concentrations were found to be as the expected ones at the given underground places and were similar to our former measurements. In the case of thoron the results are very variable and significant part of the detectors provides no data or unrealistic data. Concerning the second point there was only a little difference (<10%) between the radon results provided by the two types of detectors. In the case of thoron the two detector types showed high inconsistency. The study suggests that both types of detectors are fit for the integrating radon measurement at these special circumstances but it cannot be stated the same for the thoron measurement. The reason of the unreliability of the thoron measurement could be the high humidity (especially in the caves), the high aerosol concentration (especially in the mines) and the air change rate variation. To find the reasons needs further study. (author)

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

    International Nuclear Information System (INIS)

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

    2014-08-01

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

  10. 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)

  11. Airflow measurement techniques applied to radon mitigation problems

    International Nuclear Information System (INIS)

    Harrje, D.T.; Gadsby, K.J.

    1989-01-01

    During the past decade a multitude of diagnostic procedures associated with the evaluation of air infiltration and air leakage sites have been developed. The spirit of international cooperation and exchange of ideas within the AIC-AIVC conferences has greatly facilitated the adoption and use of these measurement techniques in the countries participating in Annex V. But wide application of such diagnostic methods are not limited to air infiltration alone. The subject of this paper concerns the ways to evaluate and improve radon reduction in buildings using diagnostic methods directly related to developments familiar to the AIVC. Radon problems are certainly not unique to the United States, and the methods described here have to a degree been applied by researchers of other countries faced with similar problems. The radon problem involves more than a harmful pollutant of the living spaces of our buildings -- it also involves energy to operate radon removal equipment and the loss of interior conditioned air as a direct result. The techniques used for air infiltration evaluation will be shown to be very useful in dealing with the radon mitigation challenge. 10 refs., 7 figs., 1 tab

  12. Radon measurements using track detector in Wadi Sannur cave

    International Nuclear Information System (INIS)

    Shahin, F.; Eissa, M.F.; Mostafa, R.M.

    2008-01-01

    The most important contributors to the committed effective dose received by population due to natural sources are the short-lived decay products of radon ( 222 Rn). In natural voids, such as caves, most radon will enter the system from diffusion across the rock-air interface. It is well known that factors such as air pressure and temperature control the distribution of radon. The radon concentration measurements in the Wadi Sannur cave in Beni-Suef governorate in the period from 14 th of July 2005 to 17 th of October 2005. The average radon concentrations in the right, left and whole first cave are 916.12 ± 179.09, 819.63 ± 54.72 and 873.90± 147.11 Bq m -3 respectively. The measurements were performed using track etch detector of type Cr-39. After exposure, all detectors were etched chemically in 6.25 M NaOH solution at 70 C degrees for 6 h. The tracks were counted with an optical microscope magnifying 400 times. The average temperature inside the first cave during the period of measurements is 25-26 C degrees. The annual effective doses for the workers and visitors in the cave have been calculated. The average radon concentration in the Wadi Sannur cave, was 873.90 ± 147.11 Bq m -3 . The annual effective doses for worker and visitor in the cave were 1.33 ± 0.24 and 0.041 ± 0.007 mSv respectively. The doses are within the international recommended dose of 1.15 mSv. (author)

  13. 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)

  14. 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

  15. The Innovative Design of Lucas Cell for Radon Gas Measurement

    International Nuclear Information System (INIS)

    Wanabongse, Paitoon; Rattanabussayaporn, Sakon; Sriya, Maitree; Sola, Banthom

    2007-08-01

    Full text: Lucas scintillation cell has been widely used for radon gas measurement. They are commercially available but usually with a rather high price, therefore, four cells were developed and built in house. The invented radon gas detector has a special feature; the circumference of the upper part of the cylindrical detector is larger than the lower part. The purpose of this is to allow the light sensing device coupled at the lower end can better detect the phosphorescence light occurred inside. The result is that the invented detector yields higher detection efficiency. This special feature also allows us to increase the volume of the detector which results in higher detection sensitivity

  16. Radioactivity on the surfaces of computer monitors and television screens due to progeny palatal

    International Nuclear Information System (INIS)

    Abdel-Nady, A.; Morsy, A.A.

    2002-01-01

    Computer monitors and television screens can collect radon progeny. Radon decay forming meta-stable progeny, namely, Po-218, Po-214, and Po-210, which are found mostly in positively, charged aerosol particles. These particles are attract by the large negative field of a video display terminals (VDT) leading to buildup of radioactivity on the VDT screen. The charged aerosol particles might drift in the electric field between the VDT and the operator and be accelerated into the operator's face. The aim of this work is to measure these phenomena set of ultra-sensitive TASTRAK detectors used to measure the plate out of positively charged radioactive radon progeny. The track detectors were fixed on the outer monitor screen. For an occupational computer worker spending 200 days per year for 6 hours a day. It was found that the mean dose equivalent was 1.77 mSv, 0.25 mSv/year for normal CRT and LCD monitors respectively

  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. Measurements of radon in drinking water (Curitiba, PR, Brazil)

    International Nuclear Information System (INIS)

    Correa, Janine Nicolosi; Paschuk, Sergei A.; Schelin, Hugo R.; Barbosa, Laercio; Sadula, Tatyana; Matsuzaki, Cristiana A.

    2009-01-01

    Full text: Among the principle mechanisms that bring the radon inside the dwelling is the exhalation and release from the water. It was evaluated that considering the latest mechanism, the exhalation of radon from the water represents about 89% of the cancer risk and the consumption of water with high concentration of radon is related to about 11% of risk cancer. Radon concentration in water could be subject of different factors such as the geology of the area, bottom sediments and inputs from streams, temperature, atmospheric pressure, etc. It is well known that the solubility of radon in water is about 510 cm 3 kg -1 at 0 deg C and decreases at higher temperatures. The 222 Rn concentration in various types of natural water in different countries usually is about few Bq/L and is the subject of the National