Indoor randon concentration. Temperature and wind effects; Concentrazione di radon indoor. Effetto del vento e della temperatura

Energy Technology Data Exchange (ETDEWEB)

Sesana, L.; Benigni, S. [Milan Univ., Milan (Italy). Ist. di Fisica Generale Applicata

2000-12-01

The present study analyses and discusses the behaviour of the indoor radon concentration in a research house. Hourly measurements were carried out in the basement of the house from November 1998 up to June 1999. In many sequences of days radon concentration in the room under analysis shows strong variation all day long with accumulation in the evening and overnight and decrease in the morning and in the afternoon. Measurements of wind velocity, indoor and outdoor temperatures and outdoor-indoor pressure difference were performed and their trend is compared with the observed radon concentration. The exhalation of radon from walls, floor and ceiling and the pressure difference driven exhalation from the soil are discussed, particularly the relation with the temperature differences. The air exchange rates between the house and the outdoor air are studied. [Italian] Si analizza e si discute il comportamento della concentrazione di radon indoor nel seminterrato di una casa di ricerca. Misure orarie sono state effettuate da novembre 1998 a giugno 1999. In molte sequenze di giorni la concentrazione del radon nel locale in analisi presenta forti variazioni nel corso della giornata con un accumulo notturno e decrescita nelle ore diurne. Sono state eseguite misure della velocita' del vento, delle temperature outdoor e indoor e della differenza di pressione outdoor-indoor e il loro andamento e' stato confrontato con quello della concentrazione del radon. Vengono discusse l'esalazione del radon dalle pareti, dal pavimento e dal soffitto e l'esalazione pressure difference driven dal suolo. Il rateo dei ricambi d'aria tra il locale e l'aria outdoor e' studiato.

Sampling strategies for indoor radon investigations

International Nuclear Information System (INIS)

Prichard, H.M.

1983-01-01

Recent investigations prompted by concern about the environmental effects of residential energy conservation have produced many accounts of indoor radon concentrations far above background levels. In many instances time-normalized annual exposures exceeded the 4 WLM per year standard currently used for uranium mining. Further investigations of indoor radon exposures are necessary to judge the extent of the problem and to estimate the practicality of health effects studies. A number of trends can be discerned as more indoor surveys are reported. It is becoming increasingly clear that local geological factors play a major, if not dominant role in determining the distribution of indoor radon concentrations in a given area. Within a giving locale, indoor radon concentrations tend to be log-normally distributed, and sample means differ markedly from one region to another. The appreciation of geological factors and the general log-normality of radon distributions will improve the accuracy of population dose estimates and facilitate the design of preliminary health effects studies. The relative merits of grab samples, short and long term integrated samples, and more complicated dose assessment strategies are discussed in the context of several types of epidemiological investigations. A new passive radon sampler with a 24 hour integration time is described and evaluated as a tool for pilot investigations

Application of a radon model to explain indoor radon levels in a Swedish house

International Nuclear Information System (INIS)

Font, LL.; Baixeras, C.; Joensson, G.; Enge, W.; Ghose, R.

1999-01-01

Radon entry from soil into indoor air and its accumulation indoors depends on several parameters, the values of which normally depend on the specific characteristics of the site. The effect of a specific parameter is often difficult to explain from the result of indoor radon measurements only. The adaptation of the RAGENA (RAdon Generation, ENtry and Accumulation indoors) model to a Swedish house to characterise indoor radon levels and the relative importance of the different radon sources and entry mechanisms is presented. The building is a single-zone house with a naturally-ventilated crawl space in one part and a concrete floor in another part, leading to different radon levels in the two parts of the building. The soil under the house is moraine, which is relatively permeable to radon gas. The house is naturally-ventilated. The mean indoor radon concentration values measured with nuclear track detectors in the crawl-space and concrete parts of the house are respectively 75±30 and 200±80 Bq m -3 . Results of the model adaptation to the house indicate that soil constitutes the most relevant radon source in both parts of the house. The radon concentration values predicted by the model indoors fall into the same range as the experimental results

Distribution of indoor radon concentrations and uranium-bearing rocks in Texas

International Nuclear Information System (INIS)

Hudak, P.F.

1996-01-01

The purpose of this study was to compare regional patterns of indoor radon concentration with uranium-bearing rock zones and county populations in Texas. Zones yielding radon concentrations that are relatively high for Texas include shale and sandstone in northwest Texas; red beds in north-central Texas; felsic volcanic rocks in west Texas; and sandstone, limestone, and igneous rocks in central Texas. Located in northwest Tecas, only five of the 202 counties evaluated have mean indoor radon concentrations above 4.0 pCi l -1 . Two of those counties have populations above the state median of 20115. The highest county mean concentration is 8.8 pCi l -1 . Results of the study suggest that (1) regional geology influences indoor radon concentrations in Texas, (2) statewide, the radon concentrations are relatively low, (3) highly populated counties do not coincide with regions of high indoor radon concentration, and (4) regions that may warrant further monitoring include northwest Texas and, to a lesser degree, west and central Texas. (orig.)

Indoor radon levels in coastal Karnataka

International Nuclear Information System (INIS)

Narayana, Y.; Radhakrishna, A.P.; Somashekarappa, H.M.; Karunakara, N.; Balakrishna, K.M.; Siddappa, K.

1995-01-01

Indoor radon levels have been measured in selected dwellings of coastal Karnataka using LR-115 type II peelable films and it is found to vary from 28.4 to 45.6 Bq m -3 with a geometric mean value of 35.7 Bq m -3 . The annual effective dose equivalent to the population of the region due to inhalation of radon was estimated from the measured data on radon level and is found to be in the range 1.9 - 3.1 mSv y -1 with a mean value 2.4 mSv y -1 . The correlation between indoor radon level and radium content in the underlying soil were studied. No definite correlation was observed to exist between indoor radon level and radium content in soil. (author). 24 refs., 2 tabs

Exposure to unusually high indoor radon levels

International Nuclear Information System (INIS)

Rasheed, F.N.

1993-01-01

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

Application of a radon model to explain indoor radon levels in a Swedish house

CERN Document Server

Font, L; Jönsson, G; Enge, W; Ghose, R

1999-01-01

Radon entry from soil into indoor air and its accumulation indoors depends on several parameters, the values of which normally depend on the specific characteristics of the site. The effect of a specific parameter is often difficult to explain from the result of indoor radon measurements only. The adaptation of the RAGENA (RAdon Generation, ENtry and Accumulation indoors) model to a Swedish house to characterise indoor radon levels and the relative importance of the different radon sources and entry mechanisms is presented. The building is a single-zone house with a naturally-ventilated crawl space in one part and a concrete floor in another part, leading to different radon levels in the two parts of the building. The soil under the house is moraine, which is relatively permeable to radon gas. The house is naturally-ventilated. The mean indoor radon concentration values measured with nuclear track detectors in the crawl-space and concrete parts of the house are respectively 75+-30 and 200+-80 Bq m sup - sup 3...

High indoor radon concentrations in some Swedish waterworks

International Nuclear Information System (INIS)

Aakerblom, G.; Hagberg, N.; Mjoenes, L.; Heiberg, A.

2002-01-01

High indoor radon concentrations in buildings used for water treatment are not uncommon. When raw water is processed in an open system radon escapes from the water to the indoor air of the premises. It is not unusual that the staff of the waterworks have their offices in the building where the water is processed. If large volumes of water are processed and the evaporated radon can reach the workplaces the indoor radon concentration can be very high even if the radon concentration of the raw water is moderate. Groundwaters from aquifers in bedrock and soil and surface water that has been infiltrated through deposits of sand or gravel have the potential to cause high indoor radon levels. In surface water emanating directly from a lake or a river the radon concentrations are normally too low to cause problems. Three waterworks in central Sweden have been studied, Ludvika, Fredriksberg and Kolbaeck. The radon concentrations in the raw water of these waterworks are from 85 Bq/l to 300 Bq/l. Average indoor radon concentrations exceeding 17,000 Bq/m 3 have been measured in Ludvika with peaks of almost 37,000 Bq/m 3 . In Kolbaeck radon concentrations up to 56,000 Bq/m 3 have been measured. It is quite possible that employees of waterworks can receive doses exceeding 20 mSv per year (calculated according to ICRP:s dose conversion convention). Measurements of radon and gamma radiation from the waterworks are reported and methods to lower the indoor radon concentrations are discussed. (author)

Modeling of indoor radon

International Nuclear Information System (INIS)

Paschoa, A.S.

1990-01-01

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

Indoor radon risk potential of Hawaii

International Nuclear Information System (INIS)

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

2005-01-01

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

Design Criteria for Achieving Low Radon Concentration Indoors

DEFF Research Database (Denmark)

Rasmussen, Torben Valdbjørn

2016-01-01

Design criteria for achieving low radon concentration indoors are presented in this paper. The paper suggests three design criteria. These criteria have to be considered at the early stage of the building design phase to meet the latest recommendations from the World Health Organization in most...... countries. The three design criteria are; first, establishing a radon barrier facing the ground; second, lowering the air pressure in the lower zone of the slab on ground facing downwards; third, diluting the indoor air with outdoor air. Three criteria when used can prevent radon infiltration and lower...... the radon concentration in the indoor air. In addition, a cheap and reliable method for measuring the radon concentration in the air indoors is described. The provision on radon in the Danish Building Regulations complies with the latest recommendations from the World Health Organization. Radon can cause...

Methodology developed to make the Quebec indoor radon potential map

International Nuclear Information System (INIS)

Drolet, Jean-Philippe; Martel, Richard; Poulin, Patrick; Dessau, Jean-Claude

2014-01-01

This paper presents a relevant approach to predict the indoor radon potential based on the combination of the radiogeochemical data and the indoor radon measurements in the Quebec province territory (Canada). The Quebec ministry of health asked for such a map to identify the radon-prone areas to manage the risk for the population related to indoor radon exposure. Three radiogeochemical criteria including (1) equivalent uranium (eU) concentration from airborne surface gamma-ray surveys, (2) uranium concentration measurements in sediments, (3) bedrock and surficial geology were combined with 3082 basement radon concentration measurements to identify the radon-prone areas. It was shown that it is possible to determine thresholds for the three criteria that implied statistically significant different levels of radon potential using Kruskal–Wallis one way analyses of variance by ranks. The three discretized radiogeochemical datasets were combined into a total predicted radon potential that sampled 98% of the studied area. The combination process was also based on Kruskal–Wallis one way ANOVA. Four statistically significant different predicted radon potential levels were created: low, medium, high and very high. Respectively 10 and 13% of the dwellings exceed the Canadian radon guideline of 200 Bq/m 3 in low and medium predicted radon potentials. These proportions rise up to 22 and 45% respectively for high and very high predicted radon potentials. This predictive map of indoor radon potential based on the radiogeochemical data was validated using a map of confirmed radon exposure in homes based on the basement radon measurements. It was shown that the map of predicted radon potential based on the radiogeochemical data was reliable to identify radon-prone areas even in zones where no indoor radon measurement exists. - Highlights: • 5 radiogeochemical datasets were used to map the geogenic indoor radon potential. • An indoor radon potential was determined for each

Effect of fresh air ventilation on indoor radon concentration

International Nuclear Information System (INIS)

Sun Hao; Wu Jianhua; Fu Shi

2012-01-01

The radon concentration of laboratory for radon simulation (LRS) was measured by the RAD7 radon monitor, and the effect of the different fresh air ventilations on indoor radon concentration was studied and analyzed. The indoor radon concentration of LRS can be accumulated up to 2000 Bq/m 3 and the average radon exhalation rate of the LRS is 14.5 Bq · m -2 . h -1 . Furthermore, when the fresh air enters into the LRS continuously, the indoor radon concentration decreases exponentially with the increase of time. The equilibrium radon concentration and equilibrium time of LRS decrease exponentially with the increase of the rate of fresh air ventilation. In addition, the indoor radon concentration increases by accumulation with the decrease of the rate of fresh air ventilation. (authors)

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

International Nuclear Information System (INIS)

Rannou, A.

1986-12-01

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

Winter-to-winter variations in indoor radon

International Nuclear Information System (INIS)

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

1989-01-01

Indoor radon concentrations in northern Virginia and central Maryland show a strong dependence on weather. Winter tends to be associated with higher than average indoor radon, and summer with lower than average. However, compared to the winter of 1986-1987, the winter of 1987-1988 was warmer and drier. Consequently, winter-to-winter indoor radon decreased by about 25%. This winter-to-winter decrease is unexpectedly large, and simulates winter-to-summer variations that have been reported

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}.

Design Criteria for Achieving Acceptable Indoor Radon Concentration

DEFF Research Database (Denmark)

Rasmussen, Torben Valdbjørn

2016-01-01

Design criteria for achieving an acceptable indoor radon concentration are presented in this paper. The paper suggests three design criteria. These criteria have to be considered at the early stage of the building design phase to meet the latest recommendations from the World Health Organization...... in most countries. The three design criteria are; first, establishing a radon barrier facing the ground; second, lowering the air pressure in the lower zone of the slab on ground facing downwards; third, diluting the indoor air with outdoor air. The first two criteria can prevent radon from infiltrating...... from the ground, and the third criteria can dilute the indoor air. By combining these three criteria, the indoor radon concentration can be lowered achieving an acceptable level. In addition, a cheap and reliable method for measuring the radon concentration in the indoor air is described. The provision...

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)

Methodology developed to make the Quebec indoor radon potential map

Energy Technology Data Exchange (ETDEWEB)

Drolet, Jean-Philippe, E-mail: jean-philippe.drolet@ete.inrs.ca [Institut national de la recherche scientifique, Eau Terre Environnement Research Centre (ETE-INRS), 490 de la Couronne, G1K 9A9 Quebec (Canada); Martel, Richard [Institut national de la recherche scientifique, Eau Terre Environnement Research Centre (ETE-INRS), 490 de la Couronne, G1K 9A9 Quebec (Canada); Poulin, Patrick [Institut national de santé publique du Québec (INSPQ), 945 avenue Wolfe, G1V 5B3 Quebec (Canada); Dessau, Jean-Claude [Agence de la santé et des services sociaux des Laurentides, 1000 rue Labelle, J7Z 5 N6 Saint-Jérome (Canada)

2014-03-01

This paper presents a relevant approach to predict the indoor radon potential based on the combination of the radiogeochemical data and the indoor radon measurements in the Quebec province territory (Canada). The Quebec ministry of health asked for such a map to identify the radon-prone areas to manage the risk for the population related to indoor radon exposure. Three radiogeochemical criteria including (1) equivalent uranium (eU) concentration from airborne surface gamma-ray surveys, (2) uranium concentration measurements in sediments, (3) bedrock and surficial geology were combined with 3082 basement radon concentration measurements to identify the radon-prone areas. It was shown that it is possible to determine thresholds for the three criteria that implied statistically significant different levels of radon potential using Kruskal–Wallis one way analyses of variance by ranks. The three discretized radiogeochemical datasets were combined into a total predicted radon potential that sampled 98% of the studied area. The combination process was also based on Kruskal–Wallis one way ANOVA. Four statistically significant different predicted radon potential levels were created: low, medium, high and very high. Respectively 10 and 13% of the dwellings exceed the Canadian radon guideline of 200 Bq/m{sup 3} in low and medium predicted radon potentials. These proportions rise up to 22 and 45% respectively for high and very high predicted radon potentials. This predictive map of indoor radon potential based on the radiogeochemical data was validated using a map of confirmed radon exposure in homes based on the basement radon measurements. It was shown that the map of predicted radon potential based on the radiogeochemical data was reliable to identify radon-prone areas even in zones where no indoor radon measurement exists. - Highlights: • 5 radiogeochemical datasets were used to map the geogenic indoor radon potential. • An indoor radon potential was determined for

Comparisons of indoor radon to other radiation hazards

International Nuclear Information System (INIS)

Bodansky, D.; Jackson, K.L.; Geraci, J.P.

1987-01-01

The significance of radon as a cause of cancer can be put into perspective by a comparison with other causes of cancer. Lung cancer is fatal in about 90% of the cases and therefore in assessing radon exposures it is pertinent to make a comparison in terms of mortality figures. There is a broad range of estimates for the U.S. lung cancer mortality from indoor radon, extending from well below 5,000 to above 20,000 per year. For simplicity in making comparisons, the authors use an intermediate estimate of 10,000 per year, although one needs to bear in mind this number is uncertain. Given approximately 480,000 fatal cancers in the United States per year and 136,000 fatal lung cancers, this estimate corresponds to indoor radon being responsible for 2% of all cancer mortality and 7% of lung cancer mortality. It is estimated that 83% of lung cancers are due to smoking, corresponding to about 113,000 deaths per year. Overall, therefore, smoking is far more important than indoor radon as a cause of lung cancer. Despite the authors' concentration on it, radon is a relatively small contributor in the perspective of cancer as a whole or even of lung cancer alone. It is a more dominant contributor in considering average exposures to ionizing radiation

An investigation of factors influencing indoor radon concentrations

International Nuclear Information System (INIS)

Majborn, B.; Soerensen, A.; Nielsen, S.P.; Boetter-Jensen, L.

1988-05-01

Variations in indoor radon concentrations and some influencing factors have been studied during a two-year period (1986-1987) in 16 almost identical single-family houses.The annual average radon concentration in the houses varied from about 50 to about 400 Bq/m 3 . Variations in soil characteristics and radon concentration in soil gas could not be directly related to the variations of the average indoor radon concentrations. Most of the houses showed a ''normal'' seasonal variation of the radon concentration with a maximum in the winter and minimum in the summer. A deviating seasonal variation was found in three of the houses. Hourly data obtained in one unoccupied house during a period of 2-1/2 months showed no or only weak correlations between the indoor radon concentration and meteorological factors. However, for most of the houses, the seasonal variation of the indoor radon concentration was well correlated with the average indoor-outdoor temperature difference on a 2-month basis. It was demonstrated that the radon concentration can be strongly reduced in the Risoe houses if a district-heating duct, which is connected to all the houses, is ventilated, so that a slightly lowered pressure is maintained in the duct. 5 taps., 24 ill. (author)

Normal and seasonally amplified indoor radon levels

International Nuclear Information System (INIS)

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

1995-01-01

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

Indoor radon measurements in the dwellings of Punjab and Himachal Pradesh, India

International Nuclear Information System (INIS)

Rani, A.; Singh, S.; Duggal, V.

2013-01-01

The measurement of indoor radon concentrations were performed in the dwellings of the Punjab and Himachal Pradesh, India by using LR-115 type II Solid-State Nuclear Track Detectors in the bare mode. The annual average indoor radon concentrations in the dwellings are found to vary from 114 to 400 Bq m -3 with an average of 194 Bq m -3 . In ∼22 % of the dwellings the indoor radon activity concentration values lies in the range of action level (200-300 Bq m -3 ) and in ∼11 % of the dwellings above the upper limit of action level recommended by the International Commission on Radiological Protection (ICRP). The annual effective dose (AED) varies from 2.88 to 10.08 mSv with an average of 4.88 mSv. In most of the villages, the AED lies in the range of action level (3-10 mSv) recommended by the ICRP. The seasonal variation in indoor radon reveals the maximum values in winter and minimum in summer. The winter/summer ratio of indoor radon ranges from 1.15 to 1.62 with an average of 1.31. Analysis of ventilation conditions reveal that the indoor radon concentration values are more in poorly ventilated dwellings compared with the well-ventilated ones. (authors)

Indoor radon level in schools of Shillong, Meghalaya

International Nuclear Information System (INIS)

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

2010-01-01

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

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.

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)

Indoor radon variations in central Iran and its geostatistical map

Science.gov (United States)

Hadad, Kamal; Mokhtari, Javad

2015-02-01

We present the results of 2 year indoor radon survey in 10 cities of Yazd province in Central Iran (covering an area of 80,000 km2). We used passive diffusive samplers with LATEX polycarbonate films as Solid State Nuclear Track Detector (SSNTD). This study carried out in central Iran where there are major minerals and uranium mines. Our results indicate that despite few extraordinary high concentrations, average annual concentrations of indoor radon are within ICRP guidelines. When geostatistical spatial distribution of radon mapped onto geographical features of the province it was observed that risk of high radon concentration increases near the Saqand, Bafq, Harat and Abarkooh cities, this depended on the elevation and vicinity of the ores and mines.

Study of a Greek area with enhanced indoor radon concentrations

International Nuclear Information System (INIS)

Louizi, A.; Nikolopoulos, D.; Koukouliou, V.; Kehagia, K.

2003-01-01

In this paper the focus is on Arnea Chalkidikis, an area in Greece with granitic geological background and indications of possible elevated radon concentration indoors. Data are reported of indoor radon measurements with etched track detectors and those used for dosimetric estimations. Moreover, data are reported on soil gas and soil radon concentrations in Arnea, as well as radon and uranium concentrations in water samples. From the measured radon concentrations in water samples the contribution to the overall dose has been calculated. For a period of 1 month, indoor radon and progeny activity has also been monitored in the dwelling that has the maximum indoor radon concentration in Greece. This dwelling is in Arnea and the dose delivered to the inhabitants has been calculated. Mean annual effective dose due to indoor radon was 4.5 mSv and about 11% of this was due to the use of water. Mean soil gas concentration and soil radon concentration were (90 ± 30) kBq m -3 (P -3 (P -1 (P<0.05). (author)

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

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

Indoor radon monitoring in the Mandi district of Himachal Pradesh, India, for health hazard assessment

International Nuclear Information System (INIS)

Kumar, G.; Kumar, A.; Walia, V.; Kumar, M.; Tuccu, M.A.; Prasher, S.

2016-01-01

In the present study, indoor radon equilibrium equivalent concentration monitoring was carried out using Solid-State Nuclear Track Detectors in some residential areas of the Mandi district, Himachal Pradesh, India. The average value of the indoor radon equilibrium equivalent concentration in the study area was found to be 94 Bq m -3 , with an annual effective dose of 1.61 mSv. The average value of the indoor radon equilibrium equivalent concentration in the studied areas was found to be higher than the world average indoor radon value of 40 Bq m -3 but lower than the value of the action level 300 Bq m -3 , except for two locations. (authors)

Development of a model for radon concentration in indoor air

International Nuclear Information System (INIS)

Jelle, Bjørn Petter

2012-01-01

A model is developed for calculation of the radon concentration in indoor air. The model takes into account various important parameters, e.g. radon concentration in ground, radon diffusion resistance of radon barrier, air permeance of ground, air pressure difference between outdoor ground and indoor at ground level, ventilation of the building ground and number of air changes per hour due to ventilation. Characteristic case studies are depicted in selected 2D and 3D graphical plots for easy visualization and interpretation. The radon transport into buildings might be dominated by diffusion, pressure driven flow or a mixture of both depending on the actual values of the various parameters. The results of our work indicate that with realistic or typical values of the parameters, most of the transport of radon from the building ground to the indoor air is due to air leakage driven by pressure differences through the construction. By incorporation of various and realistic values in the radon model, valuable information about the miscellaneous parameters influencing the indoor radon level is gained. Hence, the presented radon model may be utilized as a simple yet versatile and powerful tool for examining which preventive or remedial measures should be carried out to achieve an indoor radon level below the reference level as set by the authorities. - Highlights: ► Model development for calculation of radon concentration in indoor air. ► Radon model accounting for various important parameters. ► Characteristic case studies depicted in 2D and 3D graphical plots. ► May be utilized for examining radon preventive measures.

Indoor radon problem in energy efficient multi-storey buildings.

Science.gov (United States)

Yarmoshenko, I V; Vasilyev, A V; Onishchenko, A D; Kiselev, S M; Zhukovsky, M V

2014-07-01

Modern energy-efficient architectural solutions and building construction technologies such as monolithic concrete structures in combination with effective insulation reduce air permeability of building envelope. As a result, air exchange rate is significantly reduced and conditions for increased radon accumulation in indoor air are created. Based on radon survey in Ekaterinburg, Russia, remarkable increase in indoor radon concentration level in energy-efficient multi-storey buildings was found in comparison with similar buildings constructed before the-energy-saving era. To investigate the problem of indoor radon in energy-efficient multi-storey buildings, the measurements of radon concentration have been performed in seven modern buildings using radon monitoring method. Values of air exchange rate and other parameters of indoor climate in energy-efficient buildings have been estimated. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

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.

Investigations on indoor radon in Austria, Part 1: Seasonality of indoor radon concentration

International Nuclear Information System (INIS)

Bossew, Peter; Lettner, Herbert

2007-01-01

In general, indoor radon concentration is subject to seasonal variability. The reasons are to be found (1) in meteorological influence on the transport properties of soil, e.g. through temperature, frozen soil layers and soil water saturation; and (2) in living habits, e.g. the tendency to open windows in summer and keep them closed in winter, which in general leads to higher accumulation of geogenic Rn in closed rooms in winter. If one wants to standardize indoor Rn measurements originally performed at different times of the year, e.g. in order to make them comparable, some correction transform as a function of measurement time which accounts for these effects must be estimated. In this paper, the seasonality of indoor Rn concentration measured in Austria is investigated as a function of other factors that influence indoor Rn. Indoor radon concentration is clearly shown to have seasonal variability, with higher Rn levels in winter. However, it is complicated to quantify the effect because, as a consequence of the history of an Rn survey, the measurement season maybe correlated to geological regions, which may introduce a bias in the estimate of the seasonality amplitude

Distribution of indoor radon levels in Mexico

CERN Document Server

Espinosa, G; Rickards, J; Gammage, R B

1999-01-01

Our laboratory has carried out a systematic monitoring and evaluation of indoor radon concentration levels in Mexico for ten years. The results of the distribution of indoor radon levels for practically the entire country are presented, together with information on geological characteristics, population density, socioeconomic levels of the population, and architectural styles of housing. The measurements of the radon levels were made using the passive method of nuclear tracks in solids with the end-cup system. CR-39 was used as the detector material in combination with a one-step chemical etching procedure and an automatic digital- image counting system. Wherever a high level was measured, a confirming measurement was made using a dynamic method. The results are important for future health studies, including the eventual establishment of patterns for indoor radon concentration, as it has been done in the USA and Europe.

Correlation between indoor radon and soil gas availability: Results of field studies

International Nuclear Information System (INIS)

Kothari, B.K.; Kunz, C.; Lilley, W.

1990-01-01

To correlate indoor radon concentrations with soil gas, the authors have carried out a field survey of surficial material in selected regions of New York State. The survey consisted of measurements of gamma radiation, Ra-226, Rn-222 and the permeability for gas flow in surficial material. Based on the data, three areas with a potential for above average indoor radon concentrations have been identified: (1) a black shale region in Onondaga County; (2) a granitic region in Orange County; and (3) a black shale region in Erie County. For an area with potential for below-average indoor radon concentrations, sandy deposits on Long Island with an average concentration of 0.7 pCi Ra-226/g and 160 pCi Rn-222/L at 2-feet depth, have been selected. Fifteen homes from each of these four areas are under test for indoor radon. Measurements of air infiltration rates and soil gas availability parameters are planned for all 60 homes

Indoor radon concentrations in kindergartens from different regions of Yugoslavia

International Nuclear Information System (INIS)

Vaupotic, J.; Krizman, M.; Sutej, T.

1992-01-01

In the winter period of 1990-1991 instantaneous radon concentrations in air were measured in around 450 kindergartens from different regions from Yugoslavia. Alpha scintillation counting was used as a screening method, and the measurements were carried out in rooms where the children spent the majority of their time. All of the air grab samples were taken under the same conditions which excluded ventilation of the interior 12 h prior to sampling. In addition to indoor radon concentrations, gamma dose rate was measured using portable equipment. The indoor radon concentrations were generally low, in the range from 10 to 180 Bq.m -3 of air, with an overall average of about 100 Bq.m -3 . There were a few exceptions where indoor radon levels exceeded 150 Bq.m -3 ; mainly in old buildings containing higher contents of natural radionuclides in the building materials, and in the cellars or basements of the buildings. In all rooms with a level exceeding 150 Bq of 222 Rn per m 3 , solid-state nuclear track detectors were applied for long-term measurements. In order to investigate the equilibrium between radon and its short-lived daughters, mainly with respect to their contribution to the effective dose, alpha spectrometry is also being introduced in selected kindergartens with elevated radon concentrations. (author)

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

Energy Technology Data Exchange (ETDEWEB)

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

1990-11-01

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

A Realistic Human Exposure Assessment of Indoor Radon released from Groundwater

International Nuclear Information System (INIS)

Yu, Dong Han; Han, Moon Hee

2002-01-01

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

Effect of home construction on indoor radon in Virginia and Maryland

International Nuclear Information System (INIS)

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

1988-01-01

The levels of indoor radon in approximately 500 homes located in two contiguous counties of northern Virginia and southern Maryland have been measured during four consecutive, three month seasonal intervals using alpha-track detectors. These two counties represent an area of about 700 square miles. Results from the winter period show that the indoor radon levels were about twice as high as anticipated. In some areas, more than 50% of the homes had winter indoor radon levels above 4 pCi/liter, the EPA's recommended action level. For the spring and fall periods, indoor radon levels showed a considerable drop with approximately 35% of the homes above 4 pCi/L. Summer values were even lower with approximately 25% of the homes above 4 pCi/L.Indoor radon can be related to the weather, but home construction demonstrably determines indoor radon levels

Unusually amplified summer or winter indoor levels of radon

International Nuclear Information System (INIS)

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

1993-01-01

The ratios of winter/summer indoor radon levels for houses in different regions of the southern Appalachians are characterized by individual log-normal distributions with geometric means both above and below unity. In some counties and cities, subpopulations of houses have unusually exaggerated winter/summer ratios of indoor radon, as well as high indoor radon levels, during periods of either warm or cool weather. It is proposed that in many instances, houses are communicating with larger than normal underground reservoirs of radon-bearing air in hilly karst terrains; differences between the outdoor and underground air temperatures are believed to provide density gradients producing aerostatic pressure differences for seasonally directed underground transport and subsequently elevated indoor radon. These seasonal movements of air are analogous to the well-known underground chimney effects, which produce interzonal flows of air inside caves

A survey of indoor radon and particular concentration

International Nuclear Information System (INIS)

Ohta, Yukiko

1993-01-01

Lung disease risk from inhalation of radon can be enhanced by the presence of particular pollutants in indoor air. The indoor concentration of radon and particulates were measured in homes, a department store, and offices in a high building in Tokyo metropolis, as well as in homes in both northern and western Japan. Passive radon monitors were located in living rooms and offices for more than three months at 99 sites during the winter of 1988 and 1989. Indoor radon concentration ranged from 11.1 Bq/m 3 to 148 Bq/m 3 (n=99) and averaged value S.D. was 36.5±14.2 Bq/m 3 . However, the average concentration in air conditional buildings was 21.8±9.51 Bq/m 3 (n=17). Simultaneously at 65 of the radon sites, indoor particulates were collected using personal dust samplers by impaction methods. Deposited particulate concentrations on the sampler were measured and calculated in a unit of μm/m 3 . Concentrations were determined for particle sizes above and below 2.5 μm, for both smoking or non smoking sites. Consequently, concentration of particle size below 2.5 μm was high in smoking rooms. Finally, it was considered that smoking was a complex indoor pollutant as adherence of radon daughter to aerosols. (author)

An assessment of indoor radon exposure in Ireland

International Nuclear Information System (INIS)

McLaughlin, J.P.

1987-01-01

The results of measurements of indoor radon in over 700 dwellings chosen at ''random'' throughout the Republic of Ireland are presented. The median value of radon in these dwellings was found to be 37 Bq/m 3 (1 pCi/1). The distribution of indoor radon concentration appears to be approximately log-normal with about 2% of the dwellings surveyed having concentrations greater than 400 Bq/m 3 . High radon values were generally found to be more common in western and southern regions of the country than in the more densely populated eastern seabord. Using dose conversion factors in keeping with recent developments in lung dosimetry the median effective dose equivalent to occupants arising from the inhalation of radon daughters in the dwellings surveyed is estimated to be about 1.8 mSv per year. On the same basis for dwellings with indoor radon above 400 Bq/m 3 the continuous effective dose equivalent is estimated to be in excess of 20 mSv per year

A 2-year study of seasonal indoor radon variations in northern Virginia

International Nuclear Information System (INIS)

Mose, D.G.; Mushrush, G.W.; Chrosniak, C.E.

1991-01-01

The concentrations of indoor radon in the basements of homes located in northern Virginia average about 1.4 times the first-floor radon concentrations. Basement indoor radon concentrations exhibit seasonal variations that can be related to home use patterns of the occupants. Little indoor radon difference was seen between homes that have concrete block basement walls and poured concrete basement walls, but homes that use oil or gas furnaces for heating have ∼ 25% lower indoor radon than homes that use electrical heating systems. Particular geological units seem to be associated with elevated indoor radon concentrations, and several units are associated with indoor radon concentrations that exceed 4 pCi/l (the U.S. Environmental Agency action level) at some time in more than 40% of the homes. Comparative studies between indoor radon and total gamma aeroradioactivity show that aeroradioactivity can be accurately used to estimate community radon hazards. When combined with information about the home heating system, geology and aeroradioactivity can be used to identify problem homes

National survey of indoor radon levels in Croatia

International Nuclear Information System (INIS)

Radolic, V.; Vukovic, B.; Stanic, D.; Katic, M.; Faj, Z.; Lukacevic, I.; Planinic, J.; Suveljak, B.; Faj, D.; Lukic, M.

2006-01-01

National survey of indoor radon was performed by a random sampling of thousand (782 realized) dwellings in Croatia. Radon concentrations were measured for one year with LR-115 SSNT detectors and arithmetic and geometric means of 68 and 50 Bq/m 3 were obtained, respectively. The arithmetic means of radon concentrations on 20 counties were from 33 to 198 Bq/m 3 . The percentage of dwellings with radon concentrations above 200 and 400 Bq/m 3 was 5.4% and 1.8%, respectively. The average annual effective dose of the indoor radon was estimated as 2.2 mSv. (author)

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.)

Indoor radon and earthquake

International Nuclear Information System (INIS)

Saghatelyan, E.; Petrosyan, L.; Aghbalyan, Yu.; Baburyan, M.; Araratyan, L.

2004-01-01

For the first time on the basis of the Spitak earthquake of December 1988 (Armenia, December 1988) experience it is found out that the earthquake causes intensive and prolonged radon splashes which, rapidly dispersing in the open space of close-to-earth atmosphere, are contrastingly displayed in covered premises (dwellings, schools, kindergartens) even if they are at considerable distance from the earthquake epicenter, and this multiplies the radiation influence on the population. The interval of splashes includes the period from the first fore-shock to the last after-shock, i.e. several months. The area affected by radiation is larger vs. Armenia's territory. The scale of this impact on population is 12 times higher than the number of people injured in Spitak, Leninakan and other settlements (toll of injured - 25 000 people, radiation-induced diseases in people - over 300 000). The influence of radiation directly correlates with the earthquake force. Such a conclusion is underpinned by indoor radon monitoring data for Yerevan since 1987 (120 km from epicenter) 5450 measurements and multivariate analysis with identification of cause-and-effect linkages between geo dynamics of indoor radon under stable and conditions of Earth crust, behavior of radon in different geological mediums during earthquakes, levels of room radon concentrations and effective equivalent dose of radiation impact of radiation dose on health and statistical data on public health provided by the Ministry of Health. The following hitherto unexplained facts can be considered as consequences of prolonged radiation influence on human organism: long-lasting state of apathy and indifference typical of the population of Armenia during the period of more than a year after the earthquake, prevalence of malignant cancer forms in disaster zones, dominating lung cancer and so on. All urban territories of seismically active regions are exposed to the threat of natural earthquake-provoked radiation influence

Measurements of environmental radon - 222 concentrations in indoors and outdoors in Egypt

International Nuclear Information System (INIS)

Kenawy, M.A.; Morsey, A.A.; Kotb, M.A.; Osman, A.; El-Haag, A.

1990-01-01

The major contribution to population exposure from natural radiation arises from the inhalation of the decay products of radon. Substantial surveys are being conducted by several investigators to estimate the indoor and outdoor exposure nationally and to discover regional variations. In this work, radon concentration in the indoors and outdoor air was determined using the can technique and employing CR-39 solid state nuclear track detector for lengthy exposures. The range of radon - 222 activity in this survey was 54 -299 PCi.m -3 in Cairo, 22 - 171 PCi.m -3 in Alexandria and 89 - 370 PCi.m -3 in Asiut. Measurements carried out in Aswan and Sinai ranged between 98 - 411 PCi.m -3 . Values of indoors and outdoors radon concentrations were found to vary with time of day, geographic location, season and height above ground. Further work is going on to study the different parameters affecting the levels of the environmental radon. The national survey and associated studies is expected to yield data that may correlate radon activity with some respiratory diseases, particularly lung cancer. (author). 7 refs, 5 figs

Comparison of indoor radon and thoron concentrations in the urban and rural dwellings of Chhattisgarh state of India

International Nuclear Information System (INIS)

Khokhar, M.S.K.; Kher, R.S.; Rathore, V.B.; Pandey, S.; Ramachandran, T.V.

2008-01-01

In the frame of nationwide radon/thoron monitoring program, indoor radon/thoron and their progeny concentrations have been estimated for 210 dwellings situated in 8 towns (urban) and 9 villages (rural) of Chhattisgarh state of India. The measurement has been made on quarterly integrating cycle for one full year in each dwelling. Twin chamber dosimeter cup with LR-115 Type-II Solid State Nuclear Track Detector was used for the measurement of indoor radon/thoron concentration. The results show that the geometric mean of indoor thoron concentration in urban dwellings varies from 11.57 to 25.88Bqm -3 with an overall geometric mean value of 16.65Bqm -3 , while in rural dwellings it varies from 12.50 to 30.08Bqm -3 with an overall geometric mean value of 19.00Bqm -3 . The potential alpha energy concentration (PAEC) levels of thoron in the urban and rural dwellings are found to be 2.58 and 4.57 mWL, respectively. Similarly, the geometric mean of indoor radon concentrations in urban dwellings is found to vary from 20.20 to 30.13Bqm -3 with an overall geometric mean value of 25.28Bqm -3 , while in rural dwellings it varies from 15.50 to 36.05Bqm -3 with an overall geometric mean value of 27.32Bqm -3 . The PAEC levels of radon in the urban and rural dwellings are found to be 1.50 and 1.87 mWL, respectively. The dose contribution of thoron and progeny in total inhalation dose has been found to be more than 20% in all the surveyed places that show the necessity to pay attention to the presence of thoron and progeny from public health point of view

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

International Nuclear Information System (INIS)

Akbari, Keramatollah; Mahmoudi, Jafar; Ghanbari, Mahdi

2013-01-01

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

Results of indoor radon measurements in the republic of macedonia: - a review -

International Nuclear Information System (INIS)

Stojanovska, Zdenka; Boev, Blazho; Boev, Ivan

2017-01-01

Radon and its short lived decay products accumulated in indoor environment are the main source of public exposure to natural radiations. The health effects as well as a great number of natural and artificial factors affecting the radon accumulation in indoor environments are some of the motives for the scientific interest in radon issue. Following this global trend, many studies of indoor radon in the Balkan region, including the Republic of Macedonia have been conducted in the last decade. This paper is an overview of the published papers regarding indoor radon concentration measurements with nuclear track detectors in the Republic of Macedonia. It gives basic information about the spatial and temporal variability of indoor radon over the territory of the country, following by a description of the some factors which affect its variations. This review attempts: to organize available indoor radon results in order to show clear picture of the so far conducted surveys; to highlight the need for continuation of more extensive radon investigation in workplaces; to motivate the building professionals to create as much as possible mitigation methods for indoor radon reduction, to motivate the health professionals for epidemiological studies etc. (author)

Relationship between indoor radon concentrations and air exchange rate

International Nuclear Information System (INIS)

Wang Jingshu; Liu Yuyu; Yao Xiaohua; Meng Jianfeng; Zhang Yongyi; Wang Xiaohe; Yu Xiufen.

1995-01-01

The indoor concentration of radon and the air exchange rate were simultaneously measured in four empty rooms, made of brick and cement, which were located in different floors of dwelling houses in Taiyuan, Shanxi, China. SF 6 tracer gas decay method was used to measure the air exchange rate. Indoor radon was collected with the dimembrane method. When the ventilation rate increased, the concentration of radon dropped rapidly. Regression analysis indicated that the indoor concentration of radon was equal to the outdoor level of radon when the air exchange rate was greater than 3-4. SF 6 decay method was an effective and convenient method for measuring the air exchange rate. There was no marked difference in measurements obtained in different locations of a room. (N.K.)

Geologic controls on indoor radon in the Pacific Northwest

International Nuclear Information System (INIS)

Otton, J.K.; Duval, J.S.

1990-01-01

This paper reports on comparisons of average indoor radon levels, soil radium content (derived from aerial gamma-ray data), and soil characteristics for selected townships in Washington, Oregon, and Idaho which show that: soil radium content provides a first-order estimate of the relative amounts of indoor radon where soils are either of low to moderate intrinsic permeability or of permeability reduced by high moisture; in drier parts of the study area (east of the Cascade Mountains), unusually high average indoor radon levels are almost all characterized by soils that have high effective permeabilities (greater than 20 inches per hour), based on available country soil descriptions; and in the wetter parts of the study area (west of the Cascade Mountains), townships with unusually high indoor radon levels are characterized by steeply sloped soils

Environmental and indoor study of Radon concentration in San Joaquin area, Queretaro, Mexico, first results

International Nuclear Information System (INIS)

Hinojo Alonso, N.A.; Kotsarenko, A.; Yutsis, V.; Hernandez Silva, G.; Perego, P.; Fazio, M.; Grimalsky, V.; Koshevaya, S.; Foglia, F.; Cortes Silva, A.; García Martínez, R.; Martínez Reyes, J.; Norini, G.; Groppelli, G.

2013-01-01

A highly contaminated zone with a maximum over 57,000 Bq/m 3 was discovered in a populated community “Agua de Venados” during the 2009–2011 soil Radon survey in San Joaquin, Queretaro State, Mexico. The indoor Radon monitoring accomplished in 2 different époques in a nearby 4 dwellings has shown an increased Radon hazard in 1 of the 4 buildings (about 300 Bq/m 3 ) during a rainy season and highly elevated indoor Radon levels (over 400 Bq/m 3 ) already in 3 buildings during a dry season. The averaged diurnal indoor Radon variations are in a correlation with the atmospheric pressure and the air humidity and are independent on the air temperature. The maximum indoor Radon hazard for dwellings is estimated for the morning interval 5–10 a.m. - Highlights: ► Emanative zone of 57,000 Bq/m 3 was found in area “Agua de Venados”. ► Indoor Radon level in a nearby dwellings elevates during a dry season. ► Maximum risk for residents was estimated during the daily interval 5–10 a.m

Indoor radon measurements in the Women College, Dammam, Saudi Arabia

Energy Technology Data Exchange (ETDEWEB)

Al-Qahtani, Mona [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)

2005-11-15

Passive radon dosimeters, based on alpha particle etched track detectors, were used in the indoor radon survey of the College of Science for Girls in Dammam, Saudi Arabia. A total of 95 dosimeters were distributed in the academic departments and the administrative building in the College. The exposure time in all the buildings was one complete lunar year in the period October 2001-October 2002 to get the average annual indoor radon concentration. All the buildings were constructed with ready-made concrete, except the administrative building which constructed with ordinary concrete bricks. A significant difference in the average indoor radon concentrations in the two types of buildings was found. The average indoor radon concentration in the ready-made concrete buildings was 6+/-2Bqm{sup -3} whereas that for the ordinary concrete brick building was 24+/-2Bqm{sup -3}. This could be due to the fact that ready-made concrete has a significantly less voids for the radon to emanate compared with ordinary concrete bricks. The indoor radon concentration in the ground floor is slightly higher than that in the first and second floors.

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

Does natural gas increase the indoor radon levels?

International Nuclear Information System (INIS)

Abdel-Ghany, H.A.; Shabaan, D.H.

2015-01-01

The natural gas is naturally occurring hydrocarbon consists mainly of methane and includes varying amounts of other hydrocarbons, carbon dioxide and other impurities such as: nitrogen, and hydrogen sulfide. It is used domestically and industrially as a preferable energy source compared to coal and oil. Because natural gas is found in deep underground natural formations or associated with other underground hydrocarbon reservoirs, there is a potential to contain radon as a contaminant. This work was designated to measure indoor radon concentrations in dwellings supplied with natural gas compared with those not supplied with it, where radon level was estimated using solid state nuclear track detectors (CR-39). The results showed that radon concentration was significantly higher in dwellings supplied with natural gas, where it was 252.30 versus 136.19 Bqm -3 in dwelling not supplied with natural gas (P < 0.001). The mean values of radon exhalation rate was 0.02 ± 6.34 · 10 -4 Bq · m -2 · h -1 in dwellings supplied with natural gas and 0.01 +- 0.008 Bq · m -2 · h -1 in dwellings lacking it. In addition, a significant difference was observed in the mean annual effective doses (4.33 and 2.34 mSv · y -1 , respectively) between both groups. Conclusively, the data indicate that natural gas may represent a potential source of indoor radon

Effects of radon in indoor air studied

International Nuclear Information System (INIS)

Auvinen, A.

1994-01-01

Radon is an odorless, tasteless and colourless radioactive noble gas that enters indoor air from the ground. Radon causes lung cancer. A committee set up to evaluate the health risks of chemical substances has been drafting a report on radon, which will compile the major research findings on the lung cancer risk posed by radon. Animal tests have shown that even small doses of radon can cause lung cancer. Smokers seem to contract radon-induced lung cancer more readily than non-smokers. Because research findings have been conflicting, however, it is not known exactly how high the risk of lung cancer caused by indoor radon exposure really is. Several major research projects are under way to obtain increasingly accurate risk assessments. An on-going European joint project brings together several studies - some already finished, some still being worked on. In this way it will be possible to get more accurate risk assessments than from individual studies. In order to prevent lung cancer, it is important to continue the work of determining and reducing radon connects and to combat smoking. (orig.)

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.)

Variance of indoor radon concentration: Major influencing factors

Energy Technology Data Exchange (ETDEWEB)

Yarmoshenko, I., E-mail: ivy@ecko.uran.ru [Institute of Industrial Ecology UB RAS, Sophy Kovalevskoy, 20, Ekaterinburg (Russian Federation); Vasilyev, A.; Malinovsky, G. [Institute of Industrial Ecology UB RAS, Sophy Kovalevskoy, 20, Ekaterinburg (Russian Federation); Bossew, P. [German Federal Office for Radiation Protection (BfS), Berlin (Germany); Žunić, Z.S. [Institute of Nuclear Sciences “Vinca”, University of Belgrade (Serbia); Onischenko, A.; Zhukovsky, M. [Institute of Industrial Ecology UB RAS, Sophy Kovalevskoy, 20, Ekaterinburg (Russian Federation)

2016-01-15

Variance of radon concentration in dwelling atmosphere is analysed with regard to geogenic and anthropogenic influencing factors. Analysis includes review of 81 national and regional indoor radon surveys with varying sampling pattern, sample size and duration of measurements and detailed consideration of two regional surveys (Sverdlovsk oblast, Russia and Niška Banja, Serbia). The analysis of the geometric standard deviation revealed that main factors influencing the dispersion of indoor radon concentration over the territory are as follows: area of territory, sample size, characteristics of measurements technique, the radon geogenic potential, building construction characteristics and living habits. As shown for Sverdlovsk oblast and Niška Banja town the dispersion as quantified by GSD is reduced by restricting to certain levels of control factors. Application of the developed approach to characterization of the world population radon exposure is discussed. - Highlights: • Influence of lithosphere and anthroposphere on variance of indoor radon is found. • Level-by-level analysis reduces GSD by a factor of 1.9. • Worldwide GSD is underestimated.

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)

Indoor radon in Tunisian spas

International Nuclear Information System (INIS)

Labidi, S.; Al-Azmi, Darwish; Ben Salah, R.

2012-01-01

Indoor radon concentrations were measured in four well-known spas of Tunisia using nuclear track detectors. The radon concentrations in these spas were found to be in the range of 19 - 870 Bq.m -3 . The equilibrium factor F between radon and its progeny was found to vary in the range of 0.2 - 0.5, depending upon the ventilation rates within the buildings of the spas. Using the exposure-dose conversion factor, the effective doses to patients and workers were estimated and the dose was found to vary in the range 3.7 x 10 -3 - 12.5 x 10 -3 mSv.y -1 and 0.45 - 1.5 mSv.y -1 for patients and workers, respectively. These values are well inside the limit recommended for the annual dose limit of 20 mSv.y -1 for an occupational worker. The radium content in the groundwater of all four spas was measured and the results showed no correlation between the 226 Ra concentration in water and radon concentration in indoor air of the investigated spas. (authors)

Indoor radon and childhood leukaemia

International Nuclear Information System (INIS)

Raaschou-Nielsen, O.

2008-01-01

This paper summarises the epidemiological literature on domestic exposure to radon and risk for childhood leukaemia. The results of 12 ecological studies show a consistent pattern of higher incidence and mortality rates for childhood leukaemia in areas with higher average indoor radon concentrations. Although the results of such studies are useful to generate hypotheses, they must be interpreted with caution, as the data were aggregated and analysed for geographical areas and not for individuals. The seven available case - control studies of childhood leukaemia with measurement of radon concentrations in the residences of cases and controls gave mixed results, however, with some indication of a weak (relative risk < 2) association with acute lymphoblastic leukaemia. The epidemiological evidence to date suggests that an association between indoor exposure to radon and childhood leukaemia might exist, but is weak. More case - control studies are needed, with sufficient statistical power to detect weak associations and based on designs and methods that minimise misclassification of exposure and provide a high participation rate and low potential selection bias. (authors)

Indoor Radon and Lung Cancer Risk in Osijek

International Nuclear Information System (INIS)

Planinic, J.; Vukovic, B.; Faj, Z.; Radolic, V.; Culo, D.; Smit, G.; Suveljak, B.; Stanic, D.; Faj, D.

2001-01-01

Full text: Although studies of radon exposure have established that Rn decay products are a cause of lung cancer among miners, the lung cancer risk to the general population from indoor radon remains unclear. Our investigation of indoor radon influence on lung cancer incidence was carried out for 188 cases of the disease appeared in Osijek town during last five years. Radon concentration was measured in homes of the patients as well as for a control group. An ecologic method was applied by using the town map with square fields of 1,1km2 and the town was divided into 24 fields. For indoor radon level in the fields and belonging number of the diseases, a positive correlation coefficient was obtained, that was statistically significant, and a linear regression equation of cancer mortality rates was determined. In the mentioned population of the patients, subgroups of smokers and nonsmokers, males and females were also particularly investigated. (author)

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.)

Factors influencing indoor concentrations of radon and daughter products

International Nuclear Information System (INIS)

Wang Hengde

1985-01-01

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

Study on indoor radon exposure and its effect on human health

International Nuclear Information System (INIS)

Lu Xinwei

2005-01-01

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

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

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

Aerosol properties of indoor radon decay products

International Nuclear Information System (INIS)

Martell, E.A.

1984-01-01

Lung cancer risks attributable to indoor radon are highly dependent on the properties of radon progeny aerosols which, in turn, are dependent on the nature and concentration of small particles in indoor air. In clean filtered air, radon progeny are attached to small hygroscopic particles of high mobility which are rapidly deposited on surfaces. By contrast, radon progeny attached to cigarette smoke are on large particles of low mobility which persist in air. Radon progeny ingaled by smokers are largely associated with smoke particles from 0.5 to 4.0 μm diameter. Such particles are selectively deposited at bronchial bifurcations and are highly resistant to dissolution. The attached radon progeny undergo a substantial degree of radioactive decay at deposition sites before clearance which gives rise to large alpha radiation doses in small volumes of bronchial epithelium. These processes provide new insights on mechanisms of bronchial cancer induction and on relative risks of lung cancer in smokers, passive smokers, and other non-smokers. (Author)

Radon reduction and radon-resistant construction demonstrations in New York state. Final report

International Nuclear Information System (INIS)

1991-02-01

A survey of radon levels in New York State homes indicates that approximately 4.4 percent of the homes have long-term living area radon concentrations above the U.S. EPA guideline of four pCi/l. The project addressed the effectiveness of techniques to reduce the radon level in existing homes and to prevent the occurrence of high radon concentrations in new homes. The goal of the project was to demonstrate the effectiveness of radon reduction techniques in homes containing indoor radon concentrations of more than the current EPA guidelines of four pCi/l. At the same time, radon-resistant construction techniques were demonstrated in homes under construction to provide guidelines for houses being built in areas with a danger of high radon levels. The project demonstrated new radon mitigation techniques in homes containing indoor radon concentrations exceeding four pCi/l; assessed the value of previously installed radon reduction procedures, and demonstrated new radon-resistant construction methods

Estimation of the variations of ventilation rate and indoor radon concentration using the observed wind velocity and indoor-outdoor temperature difference

International Nuclear Information System (INIS)

Nagano, Katsuhiro; Inose, Yuichi; Kojima, Hiroshi

2006-01-01

The indoor radon concentration in the building depends on the ventilation rate. Measurement results of indoor-outdoor pressure difference showed the ventilation rate correlated closely with the indoor-outdoor pressure difference. The observation results showed that one of factor of indoor-outdoor pressure difference was the wind velocity. When the wind velocity is small, the ventilation rate is affected by the indoor-outdoor temperature difference and the effect depends on the wind velocity. The temporal variation of indoor radon concentration was predicted by the time depending indoor radon balance model and the ventilation rate estimated from the wind velocity and the indoor-outdoor temperature difference. The temporal variations of predicted radon concentration gave good agreement with the experimental values. The measurement method, indoor radon concentration and ventilation rate, factors of temporal variation of ventilation rate, and prediction of indoor radon concentration are reported. (S.Y.)

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

Science.gov (United States)

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

2013-06-01

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

Indoor and underground radon activity in the northern part of Bangladesh: a preliminary study

International Nuclear Information System (INIS)

Haque, A.K.F.; Islam, G.S.; Islam, M.A.

1991-01-01

CR-39 solid state nuclear track detectors were used to determine the indoor and underground radon activity at three locations in the northern part of Bangladesh. The indoor radon activity at Naogaon was found to be higher than that at Rajshahi and Ruppur. Radon concentration in the mud-built houses at Naogaon was estimated to be ∼ 500 Bq m -3 (14pCi 1 -1 ) which is more than three times the recommended limit. The underground radon emanation at Naogaon was found to be one order of magnitude higher than that at the other two places. (author)

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

Energy Technology Data Exchange (ETDEWEB)

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

1990-01-01

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

Indoor radon concentration levels in Amman, Zarka and Sault

International Nuclear Information System (INIS)

Khatibeh, A.J.A.H.; Ahmad, N.; Matiullah, A.

1997-01-01

Indoor radon concentration levels in three main cities of Jordan have been measured using CR-39 polymeric nuclear track detectors. CR-39 detectors were placed in polyethylene bags and cups. These bag and cup dosimeters were installed in randomly selected houses. The average value of indoor radon concentration level in the city of Amman was found to be 41.3 Bq m -3 with cup dosimeters and 42.6 Bq m -3 with bag dosimeters. For the district of Zarka, the average value of indoor radon concentration level measured with bag dosimeters was 33.9 Bq m -3 , whereas with cup dosimeters the level was 30.7 Bq m -3 . For Sault and its suburbs, the average value of indoor radon concentration level was found to be 51.2 Bq m -3 with bag dosimeters and 49.8 Bq m -3 with cup dosimeters. (author)

Removal of radon daughters from indoor air

International Nuclear Information System (INIS)

Jonassen, N.

1985-01-01

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

Indoor radon concentration data: Its geographic and geologic distribution, an example from the Capital District, NY

International Nuclear Information System (INIS)

Thomas, J.J.; Overeynder, H.M.; Thomas, B.R.

1995-01-01

Most studies of the geographic distribution of indoor radon levels are plotted by county or ZIP code. This method is used for the radon potential maps produced by the U.S. Environmental Protection Agency (EPA) and the New York State Department of Health (NYSDOH). The basis for the mapping is the mean or median indoor radon count for all the data provided by NYSDOH within each geographic area. While testing the indoor radon analyses provided to the authors by CMT Independent Laboratories, we discovered data that deviated markedly from the EPA and NYSDOH means for the Capital District of New York (Albany and surrounding counties). Their screening indoor radon average concentrations in pCi/L, indicate low potential for Schenectady (3.0), Saratoga (3.2), and Albany (3.7) counties; and moderate potential for Rensselaer (6.4) and Columbia (7.0) counties. Our database of over 3,000 analyses contains over 800 records of indoor radon counts above 4 pCi/L (14-47% of each county's analyses), many high enough to be rated as a serious health hazard. In order to obtain greater precision of information, the authors plotted their indoor radon data by street address using MapInfo, a geographic Information System (GIS), and StreetInfo, MapInfo's TIGER address database. We compared the geographic distribution of our data to both the Bedrock Geology and Surficial Geology Maps of New York State. The results show a striking relationship of radon concentrations to bedrock, faults and permeability of surficial material. Data being compiled and mapped by street address by the NYSDOH in Erie County in western New York, confirm our results

A statistical evaluation of the geogenic controls on indoor radon concentrations and radon risk

Energy Technology Data Exchange (ETDEWEB)

Appleton, J.D., E-mail: jda@bgs.ac.u [British Geological Survey, Kingsley Dunham Centre, Nicker Hill, Keyworth, Nottingham, NG12 5GG (United Kingdom); Miles, J.C.H. [Health Protection Agency (HPA), Radiation Protection Division, Chilton, Didcot, Oxon OX11 0RQ (United Kingdom)

2010-10-15

ANOVA is used to show that approximately 25% of the total variation of indoor radon concentrations in England and Wales can be explained by the mapped bedrock and superficial geology. The proportion of the total variation explained by geology is higher (up to 37%) in areas where there is strong contrast between the radon potential of sedimentary geological units and lower (14%) where the influence of confounding geological controls, such as uranium mineralisation, cut across mapped geological boundaries. When indoor radon measurements are grouped by geology and 1-km squares of the national grid, the cumulative percentage of the variation between and within mapped geological units is shown to be 34-40%. The proportion of the variation that can be attributed to mapped geological units increases with the level of detail of the digital geological data. This study confirms the importance of radon maps that show the variation of indoor radon concentrations both between and within mapped geological boundaries.

Radon and aldehyde concentrations in the indoor environment. Final report

International Nuclear Information System (INIS)

Moschandreas, D.J.; Rector, H.E.

1981-04-01

Findings regarding indoor air contaminants in the energy-efficient residence (EER) in Mt. Airy, Maryland are reported. The objectives of the study were to collect and analyze relevant air quality samples (specifically radon and aldehydes), characterize the indoor air quality with respect to radon and aldehydes, and develop relationships between air infiltration rates and contaminant levels. One-fifth of the measured formaldehyde concentrations were in the range that may cause health concerns. Although indoor temperature and relative humidity affect indoor HCHO concentration, the elevated formaldehyde concentrations were measured under very low air infiltration rates. The data show that ventilation of the indoor air space is somewhat effective in reducing high HCHO concentrations. The operation of the heat exchanger led to an increase of the air infiltration rate which in turn resulted in substantial reduction of formaldehyde concentrations. A considerable number of the collected samples of indoor air displayed radon concentrations at levels higher than 1.0 to 4.0 nCim -3 (assuming an equilibrium factor of 0.5, these radon levels would correspond to working levels above the health guidelines suggested by the US EPA for homes in Florida built on land reclaimed from phosphate mining). As in the case of indoor formaldehyde concentrations, elevated indoor concentrations are substantially reduced when the infiltration rate is increased. The data base shows that the use of the air to air heat exchanger leads to reduction of indoor radon concentration by increasing the residential ventilation rate

Mapping corrections for radon indoor data suggested by simulated data distributions

International Nuclear Information System (INIS)

Majerus, J.; Kies, A.; Tondeur, F.

2004-01-01

Indoor radon measurements may be considered as a stochastic function of spatial or spatio-temporal coordinates. This is characterized by a combination of deterministic and stochastic factors, including an important local 'noise' due to special indoor conditions. Radon mapping always consists in trying to smooth out the noise and possible outliers, to identify risk zones of high radon concentrations. To explore the spatial variation of radon we used indoor concentration data, obtained in Luxembourg and Belgium. These indoor radon databases have medium sampling density of 1 to 2 data per km 2 , respectively 0,3 data per km 2 . Furthermore we tried to investigate the relationship between geologic conditions and indoor radon concentrations. For indoor radon data, the best data sampling is restricted to all given house locations, thus we first investigated the ability to recover geological information with respect to the restricted indoor sampling distribution. To do so, we used simulated radon data with different sampling density and local clustering, generated by assuming specified average values depending on the coordinates, broadened by a typical log-normal noise and outliers of varying magnitude. Data clustering inside of villages and under-representation of the far field data locations leads to the well-known bull-eyes effects in mapping. Because the underlying deterministic structure of the simulated data is known, these data can be used to test different pre-treatments to apply before running a given gridding method. Adequate corrections for the non-uniform sampling distribution of radon indoor data can thus be explored. Furthermore, it is shown how simulated data can help to find good smoothing criteria. With smoothing needed, it may be difficult to find a good compromise between showing only significant features and showing more details at the risk of pointing out irrelevant details or even artifacts. Simulated data proved to be very useful in this context. In

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

Dependence of indoor radon concentration on the year of house construction

International Nuclear Information System (INIS)

Fujimoto, K.; Sanada, T.

1999-01-01

The dependence of indoor radon concentration on the year of house construction was studied using the results of two nationwide indoor radon surveys in Japan. The data of radon concentration in the surveys were classified into structure type as well as year of construction to obtain the current radon concentration for each structure type as a function of year of construction. The indoor radon concentration in wooden houses was found to be relatively constant with year of house construction until 1960, and then decreased, whereas the radon concentration in concrete houses increased sharply in houses constructed after 1970. The concentration in concrete houses built before 1975 was almost the same as that in contemporary wooden houses. However, the concentration in concrete houses built at present was about two times higher than that in wooden houses. The time trends found for wooden and concrete houses in the first nationwide indoor radon survey were confirmed by the second nationwide survey. In addition, these same time trends were mostly observed in the data classified into 7 districts in Japan. The increase of indoor radon concentration in concrete houses provides relatively high dose, and this increasing trend seems to continue, judging from the results of two nationwide surveys

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)

MEASUREMENT OF INDOOR RADON-THORON IN AIR AND EXHALATION FROM SOIL IN THE ENVIRONMENT OF WESTERN HARYANA, INDIA.

Science.gov (United States)

Mann, Nisha; Kumar, Amit; Kumar, Sushil; Chauhan, R P

2016-10-01

Measurement of indoor radon and thoron is important because the inhalation of radon-thoron and their daughters contributes more than 50 % of the total dose from natural sources. One of the important parameters to find out the contribution of soil and building materials towards indoor radon is radon exhalation rates, which can be used for estimation of indoor radon levels. The indoor radon and thoron levels from the air and radon exhalation rates from soil samples collected from two districts (Hisar and Fatehabad) of Western Haryana are measured using pin-hole-based radon-thoron dosimeter and LR-115 solid-state nuclear track detector by canister technique. The results show that the indoor radon and thoron levels from Hisar district varied from 11 to 112 and 11 to 80 Bq m -3 , while for Fatehabad district from 5 to 24 and 59 to 105 Bq m -3 , respectively, in summer season. In winter season, indoor radon and thoron levels from Hisar district varied from 15 to 43 and 32 to 102 Bq m -3 , while for Fatehabad district from 18 to 31 and 11 to 80 Bq m -3 , respectively. The indoor radon levels of 95 % locations lie well below the limit recommended by International Commission of Radiation Protection, 2011. The radon mass exhalation rate varied from 6 to 56 mBq kg -1 h -1 The radon mass exhalation rates from the soil samples were lower than the worldwide average, i.e. 56 mBq kg -1 h -1 There exists a poor correlation between indoor radon and exhalation rates. More investigations of measurement of radionuclide contents from rock and stone of study area can improve the understanding. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The Spanish indoor radon mapping strategy

International Nuclear Information System (INIS)

Sainz-Fernandez, C.; Fernandez-Villar, A.; Fuente-Merino, I.; Gutierrez-Villanueva, J.L.; Casal-Ordas, S.; Quindos-Poncela, L.S.; Martin-Matarranz, J.L.; Garcia-Talavera, M.

2014-01-01

Indoor radon mapping still represents a valuable tool for drawing the picture of the exposure of general public due to radon and radon progeny inhalation in a residential context. The information provided by means of a map is useful not only as awareness and strategic element for authorities and policy-makers, but also as a scientific start-up point in the design of epidemiological and other specific studies on exposure to natural radiation. The requirements for a good mapping are related to harmonisation criteria coming from European recommendations, as well as to national/local characteristics and necessities. Around 12 000 indoor radon measurements have been made since the Spanish national radon programme began at the end of the 1980's. A significant proportion of them resulted from the last campaign performed from 2009 to 12. This campaign completed the first version of a map based on a grid 10 x 10 km 2 . In this paper, the authors present the main results of a new map together with the criteria adopted to improve the number of measurements and the statistical significance of them. (authors)

Procedure for the characterization of radon potential in existing dwellings and to assess the annual average indoor radon concentration

International Nuclear Information System (INIS)

Collignan, Bernard; Powaga, Emilie

2014-01-01

Risk assessment due to radon exposure indoors is based on annual average indoor radon activity concentration. To assess the radon exposure in a building, measurement is generally performed during at least two months during heating period in order to be representative of the annual average value. This is because radon presence indoors could be very variable during time. This measurement protocol is fairly reliable but may be a limiting in the radon risk management, particularly during a real estate transaction due to the duration of the measurement and the limitation of the measurement period. A previous field study defined a rapid methodology to characterize radon entry in dwellings. The objective of this study was at first, to test this methodology in various dwellings to assess its relevance with a daily test. At second, a ventilation model was used to assess numerically the air renewal of a building, the indoor air quality all along the year and the annual average indoor radon activity concentration, based on local meteorological conditions, some building characteristics and in-situ characterization of indoor pollutant emission laws. Experimental results obtained on thirteen individual dwellings showed that it is generally possible to obtain a representative characterization of radon entry into homes. It was also possible to refine the methodology defined in the previous study. In addition, numerical assessments of annual average indoor radon activity concentration showed generally a good agreement with measured values. These results are encouraging to allow a procedure with a short measurement time to be used to characterize long-term radon potential in dwellings. - Highlights: • Test of a daily procedure to characterize radon potential in dwellings. • Numerical assessment of the annual radon concentration. • Procedure applied on thirteen dwellings, characterization generally satisfactory. • Procedure useful to manage radon risk in dwellings, for real

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})

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)

Indoor and soil radon measurements in the Hyblean Foreland (South-East Sicily

Directory of Open Access Journals (Sweden)

G. Alessandro

2007-06-01

Full Text Available Indoor radon behavior in two sites of SE Sicily was studied as a function of the soil radon concentration. The chosen locations were Ragusa and Modica towns, placed in the Hyblean Plateau (northern margin of the African Plate. Soil samples were analysed by gamma spectrometry to determine the amount of radionuclides. Indoor air and soil gas radon measurements were simultaneously performed in both sites using active detectors. Radon in soil was measured one meter deep. A positive correlation was obtained between indoor radon concentration and the soil gas concentration.

Understanding the origin of radon indoors: Building a predictive capability

International Nuclear Information System (INIS)

Sextro, R.G.

1985-12-01

Indoor radon concentrations one to two orders of magnitude higher than the US average of ∼60 Bq m -3 (∼1.5 pCi L -1 ) are not uncommon, and concentrations greater than 4000 Bq m -3 have been observed in houses in areas with no known artificially-enhanced radon sources. In general, source categories for indoor radon are well known: soil, domestic water, building materials, outdoor air, and natural gas. Soil is thought to be a major source of indoor radon, either through molecular diffusion (usually a minor component) or convective flow of soil gas. While soil gas flow into residences has been demonstrated, no detailed understanding of the important factors affecting the source strength of radon from soil has yet emerged. Preliminary work in this area has identified a number of likely issues, including the concentration of radium in the soil, the emanating fraction, soil type, soil moisture content, and other factors that would influence soil permeability and soil gas transport. Because a significant number of dwellings are expected to have indoor radon concentrations above guideline levels, a predictive capability is needed that would help identify geographical areas having the potential for high indoor concentrations. This paper reviews the preliminary work that has been done to identify important soil and building characteristics that influence the migration of radon and outlines the areas of further research necessary for development of a predictive method. 32 refs., 4 figs

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

International Nuclear Information System (INIS)

Espinosa, G.; Tommasino, L.

2015-01-01

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

Survey of indoor radon concentrations in Fukuoka and Kagoshima prefectures

International Nuclear Information System (INIS)

Kunugita, Naoki; Norimura, Toshiyuki; Tsuchiya, Takehiko

1990-01-01

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

Indoor radon survey in dwellings of some regions in Yemen

Energy Technology Data Exchange (ETDEWEB)

Khayrat, A.H. E-mail: akhayrat@yahoo.com; Al-Jarallah, M.I.; Fazal-ur-Rehman, X.; Abu-Jarad, F

2003-06-01

Indoor radon survey in a total of 241 dwellings, distributed in some regions of Yemen was performed, using CR-39 based radon monitors. The objective of this radon survey is to get representative indoor radon data of three regions, namely Dhamar, Taiz and Hodeidah, situated at different altitudes above sea level. The radon concentrations varied from 3 to 270 Bq m{sup -3} with an average of 42 Bq m{sup -3}. It was found that the average radon concentration in the surveyed areas increases with altitudes. The highest average radon concentration of 59 Bq m{sup -3} was found in Dhamar city while the lowest average concentration of 8 Bq m{sup -3} was found in Hodeidah city.

High indoor radon variations and the thermal behavior of eskers

International Nuclear Information System (INIS)

Arvela, H.; Voutilainen, A.; Honkamaa, T.; Rosenberg, A.

1994-01-01

Measurements of indoor radon concentrations in houses built on the Pispala esker in the city of Tampere were taken. The objective was to find connections between indoor radon concentrations, esker topography, and meteorological factors. The results show that not only the permeable soil but also subterranean air-flows in the esker strongly affect the indoor radon concentrations. The difference in temperature between the soil air inside the esker and the outdoor air compels the subterranean air to stream between the upper and lower esker areas. In winter, the radon concentrations are amplified in the upper esker areas where air flows out from the esker. In summer, concentrations are amplified in certain slope zones. In addition, wind direction affects the soil air and indoor radon concentrations when hitting the slopes at right angles. Winter-summer concentration ratios are typically in the range of 3-20 in areas with amplified winter concentration, and 0.1-0.5 in areas with amplified summer concentrations. A combination of winter and summer measurements provides the best basis for making mitigation decisions. On eskers special attention must be paid to building technology because of radon. 9 refs., 7 figs., 1 tab

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

Science.gov (United States)

Ringer, W

2014-07-01

In this paper, the importance of monitoring new building concepts is discussed. The effect of energy-efficient construction technologies on indoor radon is presented in more detail. Comparing the radon levels of about 100 low-energy and passive houses in Austria with radon levels in conventional new houses show that, in energy-efficient new houses, the radon level is about one-third lower than in conventional new houses. Nevertheless, certain features or bad practice may cause high radon levels in energy-efficient new houses. Recommendations to avoid adverse effects were set up. Furthermore, the paper deals with the effect of thermal retrofitting on indoor radon. Results from a Swiss study where 163 dwellings were measured before and after thermal retrofit yield an increase of the radon level of 26% in average. Among the various retrofit measures, replacing windows has the greatest impact on the indoor radon level. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

National indoor radon survey in Filipino homes

International Nuclear Information System (INIS)

Dela Cruz, Fe M.; Garcia, Teofilo Y.; Palad, Lorna Jean H.; Cobar, Ma. Lucia C.; Duran, Emerenciana B.

2012-01-01

This paper presents the results of the first national survey of indoor radon concentrations in different types of Filipino houses throughout the Philippines. Measurements were carried out using 2,626 CR-39 alpha track detectors that were deployed in selected houses for a period of six months. Results of analyses showed that indoor radon concentration in Filipino houses ranged from 1.4 to 57.6 Bq/m 3 with a mean value of 21.4 ± 9.2 Bq/m 3 . This leads to an estimated annual average effective dose equivalent of 0.4 mSv. There are slight differences in the mean concentrations of radon in different types of houses, which ranged from 19.4 to 25.3 Bq/m 3 . Highest mean radon concentrations were observed in houses made of concrete with a mean radon value of 25.3 ± 10.1 Bq/m 3 . Radon concentrations in the houses surveyed were below the action limits of 200 Bq/m 3 set by the National Radiological Protection Board (NRPB) and do not pose any hazard to the health of the occupants. (author)

A study of radon 222 transfer indoors

International Nuclear Information System (INIS)

Maximilien, R.; Robe, M.C.; Archimbaud, M.

1985-01-01

Indoor exposure can vary considerably depending upon the natural environment (geology, climate), man-made arrangements (building materials, insulation and ventilation systems...) or way of living. In order to specify the sources and assess their respective contribution in a given dwelling, a good knowledge of radon transfer and dispersion processes is required as well as a heavy experimental device (continuous radon and ventilation monitoring...). The study must be limited to some cases selected by a systematic measurement program either because they are representative of dwelling conditions, or preferably on account of their high radon level, the origin of which will be investigated. As a consequence, countermeasures can be developed. A pilot study has been carried out on radon transport in two houses of the Rhone river valley. The two houses -selected among 131 other ones for their high radon levels- are built with the same architectural approach and located very close to each other, yet the factors accounting for domestic exposure are quite different. Indoor parameters are at the origin of various radon concentrations in the case of low natural ventilation; conversely, outdoor parameters only seem to act in the case of high ventilation. For a larger part, however, radon seems to emanate from under the foundations of both houses [fr

How to Ensure Low Radon Concentrations in Indoor Environments

DEFF Research Database (Denmark)

Rasmussen, Torben Valdbjørn; Wraber, Ida Kristina

2011-01-01

This paper focuses on methods for measuring radon levels in the indoor air in buildings as well as on concrete solutions that can be carried out in the building to prevent radon leakage and to lower the radon concentration in the indoor air of new buildings. The radon provision in the new Danish...... Building Regulations from 2010 has been tightened as a result of new recommendations from the World Health Organization. Radon can cause lung cancer and it is not known whether there is a lower limit for its harmfulness. It is therefore important to reduce the radon concentration as much as possible in new...... buildings. The airtightness is a major factor when dealing with radon in buildings. Above the ground it is important to build airtight in compliance with energy requirements and against the ground it is important to prevent radon from seeping into the building. There is a direct connection between...

Predictors of Indoor Radon Concentrations in Pennsylvania, 1989-2013.

Science.gov (United States)

Casey, Joan A; Ogburn, Elizabeth L; Rasmussen, Sara G; Irving, Jennifer K; Pollak, Jonathan; Locke, Paul A; Schwartz, Brian S

2015-11-01

Radon is the second-leading cause of lung cancer worldwide. Most indoor exposure occurs by diffusion of soil gas. Radon is also found in well water, natural gas, and ambient air. Pennsylvania has high indoor radon concentrations; buildings are often tested during real estate transactions, with results reported to the Department of Environmental Protection (PADEP). We evaluated predictors of indoor radon concentrations. Using first-floor and basement indoor radon results reported to the PADEP between 1987 and 2013, we evaluated associations of radon concentrations (natural log transformed) with geology, water source, building characteristics, season, weather, community socioeconomic status, community type, and unconventional natural gas development measures based on drilled and producing wells. Primary analysis included 866,735 first measurements by building, with the large majority from homes. The geologic rock layer on which the building sat was strongly associated with radon concentration (e.g., Axemann Formation, median = 365 Bq/m3, IQR = 167-679 vs. Stockton Formation, median = 93 Bq/m3, IQR = 52-178). In adjusted analysis, buildings using well water had 21% higher concentrations (β = 0.191, 95% CI: 0.184, 0.198). Buildings in cities (vs. townships) had lower concentrations (β = -0.323, 95% CI: -0.333, -0.314). When we included multiple tests per building, concentrations declined with repeated measurements over time. Between 2005 and 2013, 7,469 unconventional wells were drilled in Pennsylvania. Basement radon concentrations fluctuated between 1987 and 2003, but began an upward trend from 2004 to 2012 in all county categories (p Pennsylvania, 1989-2013. Environ Health Perspect 123:1130-1137; http://dx.doi.org/10.1289/ehp.1409014.

Meteorological factors influencing on the radon concentrations in indoor and outdoor airs

International Nuclear Information System (INIS)

Kojima, Hiroshi

1989-01-01

Factors influencing radon concentrations in indoor and outdoor airs are discussed. A balance between source and loss is required in determining the radon concentration. Source refers to as the outdoor and indoor exhalation rate from the ground and the building materials. Loss is caused by turbulent diffusion outdoors and ventilation indoors. A significant factor influencing the exhalation rate of indoor and outdoor radon may be the change in atmospheric pressure. A drop of pressure feeds the high concentration air under the ground or building materials into the open air, and contributes to the increased exhalation rate. The exhalation rate of radon closely depends on the moisture content of the ground or building materials. Up to a certain level of moisture, the radon exhalation increases with increasing moisture content because the emanation power increases by a recoil effect of a fluid present in the internal pores of the materials. Beyond a certain level of moisture, the exhalation decreases rapidly because the pores are filled with water. Radon exhalated from the ground is spread out by turbulent diffusion. The turbulent diffusion may be related to wind velocity and the lapse rate of temperature. There is a remakable difference between indoor and outdoor radon concentrations. The ventilation rate of the house exerted a great effect upon the indoor radon concentration. The ventilation rate is influenced by meteorological factors together with human activities. Of such factors, wind velocity and temperature gradient between indoor and outdoor airs may be the most significant. The correlation coefficients between RaA or radon and some meteorological factors were calculated on the data from the long term measurements on radon and its decay products in and out of a house under normal living conditions. The changes in atmospheric pressure and wind velocity are found to be a significant factor in the variation of concentration of these nuclides. (N.K.)

Social marketing and the reduction of indoor radon

International Nuclear Information System (INIS)

Bierma, T.J.; Swartzman, D.

1990-01-01

Indoor radon monitoring and mitigation has apparently been conducted by only a small percentage of private homeowners despite extensive media coverage of the radon issue and public information programs at the federal, state, and local levels. Whether public education programs should be informative or persuasive is an ethical decision. Arguments on each side of the issue are presented. A framework for the development of a persuasive campaign is then presented, suing the concepts of social marketing and the limited empirical evidence available on radon-related behavior. In this paper a four-step process is proposed: identify problem dimensions using focus groups and other methods, confirm dimension for market segmentation using probability samples and factor analysis, implement program and evaluate and revise

Coordinated indoor radon surveys in some Arab countries

International Nuclear Information System (INIS)

Al-Azmi, D.; Al-Abed, T.; Alnasari, M.S.; Borham, E.E.; Chekir, Z.; Khalifa, M.S.; Shweikani, R.

2012-01-01

Indoor radon surveys were carried out in some of the Arab countries through a Coordination Research Program (CRP) organized by the Arab Atomic Energy Agency (AAEA). The objectives of the program aim at establishing a database on indoor radon concentration levels in the region and investigating any anomalies, where they exist. The approach adopted by the survey teams to achieve public participation in accepting the radon detectors in dwellings is presented and discussed. Most of the participants in the CRP used the passive method (CR-39 plastic detectors) for long-term radon measurements, while others used charcoal detectors and E-Perm systems for short-term measurements. The results of the surveys showed that radon concentration levels in most of the dwellings were low, whilst in some old cities and in an area close to a phosphate mine the levels were found to be relatively high. (authors)

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)

Geologic influence on indoor radon concentrations and gamma radiation levels in Norwegian dwellings

Energy Technology Data Exchange (ETDEWEB)

Sundal, Aud Venche

2003-09-01

Indoor radon levels in 1618 Norwegian dwellings located in different geological settings were compared with geological information in order to determine potential correlations between geological factors and indoor radon concentrations in Norway and to establish whether geological information is useful in radon risk analysis. In two geographically limited areas, Kinsarvik and Fen, detailed geological and geochemical investigations were carried out in order to explain their elevated natural radiation environment. Significant correlations between geology and indoor radon concentrations in Norway are found when the properties of both the bedrock and the overburden are taken into account. Areas of high radon risk in Norway include 1) exposed bedrock with elevated levels of radium (mainly alum shale and granites) and b) highly permeable unconsolidated sediments derived from all rock types (mainly glaciofluvial and fluvial deposits) and moderately permeable sediments containing radium rich rock fragments (mainly basal till). More than 20 % of Norwegian dwellings located in the high-risk areas can be expected to contain radon levels exceeding 200 Bq/m3. The elevated radon risk related to penneable building grounds is illustrated in Kinsarvik where the highly permeable sediments and the large vadose zone underlying the Huse residential area enable the transport of radon from large volumes into the dwellings resulting in enhanced indoor radon concentrations. Subterranean air flows caused by temperature/pressure differences between soil air and atmospheric air and elevations differences within the Huse area are shown to strongly affect the annual variations in indoor radon concentrations. The marked contrasts in radon risk potential between different types of building grounds are clearly illustrated in the Fen area where outcrops of the radium rich Fen carbonatites represent areas of high radon risk while only low levels of both indoor radon concentrations and indoor gamma

Geologic factors and house construction practices affecting indoor radon in Onondaga County, New York

International Nuclear Information System (INIS)

Laymon, C.; Kunz, C.

1990-01-01

Indoor radon in Onondaga County, New York is largely controlled by bedrock and surficial geology. At more local scales, these alone are insufficient to characterize indoor radon potential. This paper reports on a detailed study of the concentration of indoor radon, soil radium, soil-gas radon, soil and bedrock type, permeability, and home construction practices indicates that above-average indoor radon concentrations are associated with gravelly moraine and glaciofluvial deposits, the radium-bearing Marcellus Shale, and high permeability zones around the substructure of houses built into limestone bedrock

Indoor radon levels in Riyadh city dwellings

International Nuclear Information System (INIS)

Alghamdi, Abdulrahman S.; Khalid, Aleissa; Ghazi, Alzeer

2008-01-01

Full text: Building materials used for construction of houses represent a major source of indoor radon. In this investigation, indoor radon concentrations are found to vary substantially among the different building materials, ventilation, cooling and heating systems used. This paper presents the effects of these factors on the radon concentration in Riyadh city dwellings. The measurements were obtained by using a passive integrating ionization system with an E-Perm Electret ion chamber. The study covered more than 700 houses and apartments, which were selected to cover the most common type of houses. The concentration range was found to be 1.02 to 196 Bq.m -3 , with an average value of 17.5 ± 3 Bq.m -3 . The results show that the radon concentration is higher in houses where the white bricks, no ventilation systems, plastic paint and Freon air conditioners are used, but relatively lower in houses where the red bricks, window ventilation, and water air conditioner is used. (author)

Preliminary indoor radon and gamma measurements in kindergartens and schools in Bucharest

International Nuclear Information System (INIS)

Dumitrescu, A.; Milu, C.; Gheorghe, R.; Vaupotic, J.; Stegnar, P.

2001-01-01

A pilot study on indoor radon and gamma dose rates in schools and kindergartens (totalling one hundred buildings) in the Bucharest metropolitan area was performed jointly by the Institute of Public Health, Bucharest, Romania, and the J. Stefan Institute, Ljubljana, Slovenia. Because the geological structure of subsoil over the whole Bucharest area is uniform (a loess platform), the criteria for selecting a kindergarten or a school to be monitored were the age of the building and the building materials. Indoor radon concentrations were measured by a single one-month exposure of radon monitoring device based on etched track detectors in December 2000. Data show a lognormal distribution within the concentration range of 43/477 Bq/m 3 . An arithmetic mean of 146 Bq/m 3 and a geometric mean of 128 Bq/m 3 were obtained. Concomitant with indoor radon levels gamma dose rates were also measured, using thermoluminescent dosimeters. Values ranged from 54 to 100 μSv mo -1 , with a mean value of 74 μSv mo -1 . Having only a single average indoor radon concentration for a winter month, it is not possible to comment on our results, applying the ICRP Publication 65 methodology for indoor radon action level for the general public. Nevertheless, they give a preliminary picture of indoor radon and gamma dose rate levels in schools and kindergartens in Bucharest, and constitute a solid basis on which to design and perform a nation-wide radon survey programme.(author)

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)

Characterization of radon entry rates and indoor concentrations in underground structures

International Nuclear Information System (INIS)

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

1992-01-01

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

A new coating material for reducing indoor radon level

International Nuclear Information System (INIS)

Zhuo, W.; Tokonami, S.; Ichitsubo, H.; Yamada, Y.; Yamada, Y.

2002-01-01

In order to mitigate indoor radon level, a new fast-setting, solvent-free, polyurethane-based coating material was developed. The permeability of radon gas in the new material was estimated with a simple radon permeation test system set up in this study. It was found that the permeation velocity depended on the thickness of the coating material, and a thickness of 2.0 mm of the coating material seems sufficient for preventing radon permeation. The permeability of radon in the coating material was estimated to be (2.2± 0.8)x10 -10 m 2 ·s -1 for a thickness of about 1.0 mm. The value is much lower than those reported for membrane materials and caulking compounds. For its performance test, the coating material was used in an existing room with high radon level. By spraying a thickness of 1.5 mm of the material, the indoor radon level reduced by about 80%

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)

Seasonal variations of indoor radon concentrations

International Nuclear Information System (INIS)

Majborn, B.

1990-01-01

Seasonal variations of indoor radon concentrations have been studied in a cluster of 10 single-family houses. Eight of the houses are of a similar construction with slab-on-grade foundations. The remaining two houses have different substructures, one of them having a crawl space, and the other having partly a basement and partly a crawl space. A 'normal' seasonal variation of the radon concentration with a maximum in winter and a minimum in summer was observed in most of the houses. In these houses the variation showed a strong correlation with the indoor-outdoor temperature difference on a 2-month basis. However, deviating seasonal variations were observed in some of the houses, notably in the two houses having different substructures. This paper reports that a re-examination of the data obtained in a previous study indicates that winter/summer ratios of indoor radon concentrations in Danish houses depend on the house substructure. The mean winter/summer ratios were about 2.1 for houses with slab-on-grade foundations, 1.5 for houses having a basement, and 1.0 for houses with a crawl space (geometric mean values). However, a study with more houses in each substructure category will be needed to show whether or not the indicated differences are generally valid for Danish houses

Theoretical evaluation of indoor radon control using a carbon adsorption system

International Nuclear Information System (INIS)

Bocanegra, R.; Hopke, P.K.

1989-01-01

The conceptual framework for a carbon-based adsorption system for the control of indoor radon is presented. Based on the adsorptivity of typically available activated carbons, it is shown theoretically that carbon bed adsorbers can be effective in lowering indoor radon levels particularly when the area of radon ingress (the basement) has a relatively low exchange rate with the rest of the house

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

Science.gov (United States)

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

2011-03-01

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

Assessment of indoor radon gas concentration change of college

Energy Technology Data Exchange (ETDEWEB)

Park, Hoon Hee; Jeong, Eui Hwan; Kim, Hak Jae; Lyu, Kang Yeul [Dept. of of Radiological Technology, Shingu College, Seongnam (Korea, Republic of); Lee, Ju Young [Dept. of Radiological Technology, Songho College, Hoengseong (Korea, Republic of)

2017-03-15

The purpose of this study was to assess the impact by comparing the concentration of indoor radon and look for ways to lower the concentration of indoor radon gas measurements of three variables, the year of completion, volume of the building and ventilation. Measurement target is six classrooms on the sixth floor of building that was constructed in 1973 and was extended in 2011. Selected classroom's volume is different. Four classrooms were selected to compare the radon concentration in accordance with the year of completion, Classrooms that is same year of completion were selected to compare the radon concentration in accordance with the volume, six classroom was performed closure and ventilation to compare radon concentration according to ventilation. Radon concentrations in accordance with the year of building completion showed a high concentration of radon in a building recently built. Also, Radon concentration in volume is high the smaller the volume. Radon concentration change according to ventilation showed a reduction of about 80% when the ventilation than during closing. Especially, The radon concentrations were high detected while the recently year of building completion and the smaller volume. Ventilation of the three variables is considered that can be expected to exposure reduction effect by radon affecting the greatest radon concentration reduction.

Assessment of indoor radon gas concentration change of college

International Nuclear Information System (INIS)

Park, Hoon Hee; Jeong, Eui Hwan; Kim, Hak Jae; Lyu, Kang Yeul; Lee, Ju Young

2017-01-01

The purpose of this study was to assess the impact by comparing the concentration of indoor radon and look for ways to lower the concentration of indoor radon gas measurements of three variables, the year of completion, volume of the building and ventilation. Measurement target is six classrooms on the sixth floor of building that was constructed in 1973 and was extended in 2011. Selected classroom's volume is different. Four classrooms were selected to compare the radon concentration in accordance with the year of completion, Classrooms that is same year of completion were selected to compare the radon concentration in accordance with the volume, six classroom was performed closure and ventilation to compare radon concentration according to ventilation. Radon concentrations in accordance with the year of building completion showed a high concentration of radon in a building recently built. Also, Radon concentration in volume is high the smaller the volume. Radon concentration change according to ventilation showed a reduction of about 80% when the ventilation than during closing. Especially, The radon concentrations were high detected while the recently year of building completion and the smaller volume. Ventilation of the three variables is considered that can be expected to exposure reduction effect by radon affecting the greatest radon concentration reduction

Risk of Lung Cancer and Indoor Radon Exposure in France

International Nuclear Information System (INIS)

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

2004-01-01

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

Systematic measurements of the radon concentration indoor from Remetea, Harghita county

International Nuclear Information System (INIS)

Csegzi, Sandor

2000-01-01

Primary goal of the Remetea radon program was to carry out an indoor radon survey. The program can be applied too, in other places of the country. Remetea was built on volcanic rocks, where aligning of mineral water springs tells about the existence of geologic faulting. The 1992 census counted 2406 houses and 6550 residents of the village. The sample consisted of 120 houses chosen randomly from the entire stock. A hypergeometric statistical model has been used for sampling. Measurements were done in bedrooms at pillow level using etched track type Radamon radon detectors. Exposure lasted from January 1999 to July 1999. From the measurements it can be stated that the number of houses with radon concentration exceeding 200 Bq/m 3 is around 82. A high precision determination of activity has been done (errors under 3 %). Mapping indoor radon levels resembles the fault location that is indicated by springs and exhibited by geological studies. Particular points of the program were the soulful and self-aware approach the more than 30 schoolboys and girls participated, and the fact that the program met with a warm response from the public. (author)

Indoor radon in a Spanish region with different gamma exposure levels

International Nuclear Information System (INIS)

Quindos, L.S.; Fernandez, P.L.; Sainz, C.; Fuente, I.; Nicolas, J.; Quindos, L.; Arteche, J.

2008-01-01

In the beginning of 1990s within the framework of a national radon survey of more than 1500 points, radon measurements were performed in more than 100 houses located in Galicia region, in the Northwest area of Spain. The houses were randomly selected only bearing in mind general geological aspects of the region. Subsequently, a nationwide project called MARNA dealt with external gamma radiation measurements in order to draw a Spanish natural radiation map. The comparison in Galicia between these estimations and the indoor radon levels previously obtained showed good agreement. With the purpose of getting a confirmation of this relationship and also of creating a radon map of the zone, a new set of measurements were carried out in 2005. A total of 300 external gamma radiation measurements were carried out as well as 300 measurements of 226 Ra, 232 Th and 40 K content in soil. Concerning radon, 300 1-m-depth radon measurements in soil were performed, and indoor radon concentration was determined in a total of 600 dwellings. Radon content in soil gave more accurate indoor radon predictions than external gamma radiation or 226 Ra concentration in soil

Indoor radon concentrations in Vushtrri, Kosovo

International Nuclear Information System (INIS)

Xhafa, B.; Jonuzaj, A.; ); Bekteshi, S.; Ahmetaj, S.; Kabashi, S.; )

2009-01-01

Indoor air radon concentration was measured by exposing trac ketch detectors in the two elementary schools, one high school, a kindergarten and the hospital in the city of Vushtrri. Measurements were performed with the radon monitor PRM-145, which uses alpha scintillation cells and serves to determine the current concentration of radon. The results we obtained are in the range between the average values of radon for the interior spaces, and values that pose a potential risk for lung cancer. Measuring the concentration of radon was done in total of 34 rooms and came up with values which are between 28Bqm -3 and 398Bqm -3 . In order to reduce the concentration of radon, we have built a ventilation pump, then we performed repeated measurements and finally came with results between 130-145Bqm -3 .

Indoor radon measurement in some adobe houses in the Kassena Nankana area of the Upper East Region

International Nuclear Information System (INIS)

Quashie, F. K.

2010-06-01

Inhalation of radon and its daughter products is the major contributor to the total exposure of the population to natural radiation. The present study has measured radon gas concentration in some Adobe houses and the soil radon gas around these houses in the Kassena Nankana Area of the Upper East Region by using passive radon indoor dosimeter containing solid-state nuclear track detector (SSNTD) commercially known as LR - 115 (type II, pelliculable). Fifty (50) indoor radon dosimeters were placed in the various Adobe houses in the study area. Additionally, thirty (30) dosimeters were placed in the soil around some of the houses at a depth of 75 cm. Soil radon dosimeters were retrieved after two (2) weeks while the indoor radon dosimeters were retrieved after 78 to 82 days. The detectors were then chemically etched. The digital laser optic system and the spark counter coupled with microfiche reader were used in counting both the indoor and soil detectors respectively. Indoor radon concentration in the study area range from 35.28 Bq/m 3 to 244.22 Bq/m 3 . An active dosimeter known as the radon scout plus which gives instantaneous readings between 1 to 3 hours was also used in nineteen of the adobe houses in the study area and a total average radon concentration of 56.90 Bq/m3 was obtained. The soil radon concentration was also found to range from 2.12 kBq/m 3 to 15.03 kBq/m 3 . A good correlation was found to exist between the soil radon concentration and that of the indoor radon concentration with a correlation coefficient of about 0.61. The mean radon emanation coefficient of some fifteen (15) soil samples monitored was 0.46. The average annual effective dose was estimated to be about 1.66 mSv/y and that of the average annual effective dose using the equilibrium equivalent factor (F) was 1.00 mSv/y

Indoor radon and environmental gamma radiation in Hong Kong

International Nuclear Information System (INIS)

Yu, K.N.; Young, E.C.M.; Stokes, M.J.; Luo, D.L.; Zhang, C.X.

1992-01-01

Activated charcoal canisters have been used to measured the indoor radon concentrations of 160 sites in different buildings in Hong Kong during the period from July to October 1990. The average value is 40.0 Bq.m -3 . Furthermore, CR-39 nuclear track detectors and two kinds of LiF TLDs have been used to measure the average indoor radon concentrations and the absorbed gamma dose rates in air of 71 sites over the period from January to April 1991. The results all show log-normal distribution. The indoor radon concentrations are respectively 72.2 Bq.m -3 and 155.4 Bq.m -3 for dwellings and offices, while the absorbed gamma dose rates in air are respectively 213.0 nGy.h -1 and 198.3 nGy.h -1 . (author)

A feasibility study of geogenic indoor radon mapping from airborne radiometric survey in northern Thailand

Energy Technology Data Exchange (ETDEWEB)

Wattananikorn, K. [Department of Physics, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand)], E-mail: kittic@science.cmu.ac.th; Emharuthai, S. [Department of Physics, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Wanaphongse, P. [Office of Atoms for Peace, Bangkok (Thailand)

2008-01-15

Experiments were carried out in seven test sites on three Quaternary alluvial and terrace deposit basins of northern Thailand, to test the possibility of using airborne equivalent uranium to predict geogenic indoor radon values of the region. The methodology was based on the correlation among soil gas permeability, soil radon concentration and indoor radon, as well as a relationship between soil radon and airborne uranium values. The methodology established works rather well when tested in areas of known indoor radon. Based on the predicted values that were obtained from this method, indoor radon in most areas of alluvial and terrace deposit basins of northern Thailand is less than 44Bq/m{sup 3}. There is no area in these basins where predicted indoor radon exceeds 74Bq/m{sup 3}.

A numerical study on the performance evaluation of ventilation systems for indoor radon reduction

Energy Technology Data Exchange (ETDEWEB)

Lee, Ji Eun; Park, Hoon Chae; Choi, Hang Seok; Cho, Seung Yeon; Jeong, Tae Young; Roh, Sung Cheoul [Yonsei University, Wonju (Korea, Republic of)

2016-03-15

Numerical simulations were conducted using computational fluid dynamics to evaluate the effect of ventilation conditions on radon ({sup 222}Rn) reduction performance in a residential building. The results indicate that at the same ventilation rate, a mechanical ventilation system is more effective in reducing indoor radon than a natural ventilation system. For the same ventilation type, the indoor radon concentration decreases as the ventilation rate increases. When the air change per hour (ACH) was 1, the indoor radon concentration was maintained at less than 100 Bq/m{sup 3}. However, when the ACH was lowered to 0.01, the average indoor radon concentration in several rooms exceeded 148 Bq/ m{sup 3}. The angle of the inflow air was found to affect the indoor air stream and consequently the distribution of the radon concentration. Even when the ACH was 1, the radon concentrations of some areas were higher than 100 Bq/m{sup 3} for inflow air angles of 5 .deg. and 175 .deg.

Indoor radon levels in selected hot spring hotels in Guangdong, China.

Science.gov (United States)

Song, Gang; Zhang, Boyou; Wang, Xinming; Gong, Jingping; Chan, Daniel; Bernett, John; Lee, S C

2005-03-01

Guangdong is one of the provinces that have most hot springs in China, and many hotels have been set up near hot springs, with spring water introduced into the bath inside each hotel room for hot spring bathing to attract tourists. In the present study, we measured radon in indoor and outdoor air, as well as in hot spring waters, in four hot spring hotels in Guangdong by using NR-667A (III) continuous radon detector. Radon concentrations ranged 53.4-292.5 Bq L(-1) in the hot spring water and 17.2-190.9 Bq m(-3) in outdoor air. Soil gas intrusion, indoor hot spring water use and inefficient ventilation all contributed to the elevated indoor radon levels in the hotel rooms. From the variation of radon levels in closed unoccupied hotel rooms, soil gas intrusion was found to be a very important source of indoor radon in hotel rooms with floors in contact with soils. When there was spring water bathing in the bathes, average radon levels were 10.9-813% higher in the hotel rooms and 13.8-489% higher in bathes compared to their corresponding average levels when there was no spring water use. Spring water use in the hotel rooms had radon transfer coefficients from 1.6x10(-4) to 5.0x10(-3). Radon in some hotel rooms maintained in concentrations much higher than guideline levels might thus have potential health risks to the hotel workers, and technical and management measures should be taken to lower their exposure of radon through inhalation.

Indoor radon levels in selected hot spring hotels in Guangdong, China

International Nuclear Information System (INIS)

Song Gang; Zhang Boyou; Wang Xinming; Gong Jingping; Chan, Daniel; Bernett, John; Lee, S.C.

2005-01-01

Guangdong is one of the provinces that have most hot springs in China, and many hotels have been set up near hot springs, with spring water introduced into the bath inside each hotel room for hot spring bathing to attract tourists. In the present study, we measured radon in indoor and outdoor air, as well as in hot spring waters, in four hot spring hotels in Guangdong by using NR-667A (III) continuous radon detector. Radon concentrations ranged 53.4-292.5 Bq L -1 in the hot spring water and 17.2-190.9 Bq m -3 in outdoor air. Soil gas intrusion, indoor hot spring water use and inefficient ventilation all contributed to the elevated indoor radon levels in the hotel rooms. From the variation of radon levels in closed unoccupied hotel rooms, soil gas intrusion was found to be a very important source of indoor radon in hotel rooms with floors in contact with soils. When there was spring water bathing in the bathes, average radon levels were 10.9-813% higher in the hotel rooms and 13.8-489% higher in bathes compared to their corresponding average levels when there was no spring water use. Spring water use in the hotel rooms had radon transfer coefficients from 1.6x10 -4 to 5.0x10 -3 . Radon in some hotel rooms maintained in concentrations much higher than guideline levels might thus have potential health risks to the hotel workers, and technical and management measures should be taken to lower their exposure of radon through inhalation

The radon service industry in selected Northeastern states

International Nuclear Information System (INIS)

Watson, M.R.; Reese, J.P.; Adams, A.R.

1988-01-01

In 1986 the EPA initiated an expedited program of technical assistance in response to the discovery of extremely elevated levels of indoor radon in Pennsylvania homes. A vital component of this project was a training program which addressed the variety of techniques used to reduce human exposure to radon gas and its decay products. The New York State Energy Office was selected as the most suitable organization to assist in this project because of its relevant experience in training programs, especially the building for energy efficiency workshop series with its indoor radon gas component. This paper reports on the project

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

International Nuclear Information System (INIS)

Nero, A.V. Jr.

1985-04-01

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

Indoor radon concentration levels, gamma dose rates and impact of geology - A case study in Kotli, State of Azad Jammu and Kashmir, sub-Himalayas, in Pakistan

International Nuclear Information System (INIS)

Iqbal, A.; Shahid Baig, M.; Akram, M.; Qureshi, A.A.

2012-01-01

Inhalation of indoor radon has been recognized as the largest contributor to the total effective dose received by human beings. Indoor radon data were collected from the dwellings lying on the sedimentary rocks (sandstones, siltstones and clays) of the Murree Formation, Nagri Formation, Dhok Pathan Formation, Mirpur conglomerate and surficial deposits of the Kotli area in Azad Jammu and Kashmir, Pakistan. Radon measurements were made using the passive time-integrated method using Kodak CN-85 Solid-State Nuclear Track Detectors. The radon concentration in dwellings varied from 13 ± 6 Bq.m -3 to 185 ± 23 Bq.m -3 , with an average of 73 ± 15 Bq.m -3 .The radon concentration in the Murree Formation, Nagri Formation, river terrace and Dhok Pathan Formation were 89.7 ± 16.5, 72 ± 15, 68.5 and 69 Bq.m -3 , respectively. The average value of all the measured concentrations (73 ± 15 Bq.m -3 ) within the framework of this study is more than the world average value of 40 Bq.m -3 given by UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation, report to the General Assembly, United Nations, New York, 2000) and is within the action level of 200-600 Bq.m -3 fixed by the ICRP (International Commission on Radiological Protection, ICRP publication 65, Protection against radon at home and at work, 1993). The ambient gamma dose rates both indoors and outdoors in different parts of Kotli were also measured. The average value of gamma absorbed dose rates prevailing in the indoor environment was 131.2 ± 16.6 nGy/h. The gamma exposure rates recorded outdoors were 35% lower than in the indoor environment. The measured gamma dose rates have a weak positive correlation with indoor radon concentration. The annual effective dose for inhabitants in Kotli due to radon ranged from 0.32 to 4.7 mSv.y -1 , with an average value of 1.8 mSv.y -1 . This dose is relatively higher than the world mean dose of 1.15 mSv/y. That is explained by the particular geology of the

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

International Nuclear Information System (INIS)

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

2002-01-01

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

Indoor radon exposure in Norway and lung cancer risk

International Nuclear Information System (INIS)

Sanner, T.; Dybing, E.

1990-01-01

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

Variation of indoor radon concentration and ambient dose equivalent rate in different outdoor and indoor environments

Energy Technology Data Exchange (ETDEWEB)

Stojanovska, Zdenka; Janevik, Emilija; Taleski, Vaso [Goce Delcev University, Faculty of Medical Sciences, Stip (Macedonia, The Former Yugoslav Republic of); Boev, Blazo [Goce Delcev University, Faculty of Natural and Technical Sciences, Stip (Macedonia, The Former Yugoslav Republic of); Zunic, Zora S. [University of Belgrade, Institute of Nuclear Sciences ' ' Vinca' ' , Belgrade (Serbia); Ivanova, Kremena; Tsenova, Martina [National Center of Radiobiology and Radiation Protection, Sofia (Bulgaria); Ristova, Mimoza [University in Ss. Cyril and Methodius, Faculty of Natural Sciences and Mathematic, Institute of Physics, Skopje (Macedonia, The Former Yugoslav Republic of); Ajka, Sorsa [Croatian Geological Survey, Zagreb (Croatia); Bossew, Peter [German Federal Office for Radiation Protection, Berlin (Germany)

2016-05-15

Subject of this study is an investigation of the variations of indoor radon concentration and ambient dose equivalent rate in outdoor and indoor environments of 40 dwellings, 31 elementary schools and five kindergartens. The buildings are located in three municipalities of two, geologically different, areas of the Republic of Macedonia. Indoor radon concentrations were measured by nuclear track detectors, deployed in the most occupied room of the building, between June 2013 and May 2014. During the deploying campaign, indoor and outdoor ambient dose equivalent rates were measured simultaneously at the same location. It appeared that the measured values varied from 22 to 990 Bq/m{sup 3} for indoor radon concentrations, from 50 to 195 nSv/h for outdoor ambient dose equivalent rates, and from 38 to 184 nSv/h for indoor ambient dose equivalent rates. The geometric mean value of indoor to outdoor ambient dose equivalent rates was found to be 0.88, i.e. the outdoor ambient dose equivalent rates were on average higher than the indoor ambient dose equivalent rates. All measured can reasonably well be described by log-normal distributions. A detailed statistical analysis of factors which influence the measured quantities is reported. (orig.)

Indoor radon levels in selected hot spring hotels in Guangdong, China

Energy Technology Data Exchange (ETDEWEB)

Song Gang [Guangzhou Institute of Geochemistry, Chinese Academy of Science, Guangzhou 510640 (China); Zhang Boyou [Guangzhou Institute of Geochemistry, Chinese Academy of Science, Guangzhou 510640 (China); Wang Xinming [Guangzhou Institute of Geochemistry, Chinese Academy of Science, Guangzhou 510640 (China)]. E-mail: wangxm@gig.ac.cn; Gong Jingping [Guangzhou Institute of Geochemistry, Chinese Academy of Science, Guangzhou 510640 (China); Chan, Daniel [Department of Building Services Engineering, Hong Kong Polytechnic University, Hong Kong (China); Bernett, John [Department of Building Services Engineering, Hong Kong Polytechnic University, Hong Kong (China); Lee, S.C. [Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hong Kong (China)

2005-03-01

Guangdong is one of the provinces that have most hot springs in China, and many hotels have been set up near hot springs, with spring water introduced into the bath inside each hotel room for hot spring bathing to attract tourists. In the present study, we measured radon in indoor and outdoor air, as well as in hot spring waters, in four hot spring hotels in Guangdong by using NR-667A (III) continuous radon detector. Radon concentrations ranged 53.4-292.5 Bq L{sup -1} in the hot spring water and 17.2-190.9 Bq m{sup -3} in outdoor air. Soil gas intrusion, indoor hot spring water use and inefficient ventilation all contributed to the elevated indoor radon levels in the hotel rooms. From the variation of radon levels in closed unoccupied hotel rooms, soil gas intrusion was found to be a very important source of indoor radon in hotel rooms with floors in contact with soils. When there was spring water bathing in the bathes, average radon levels were 10.9-813% higher in the hotel rooms and 13.8-489% higher in bathes compared to their corresponding average levels when there was no spring water use. Spring water use in the hotel rooms had radon transfer coefficients from 1.6x10{sup -4} to 5.0x10{sup -3}. Radon in some hotel rooms maintained in concentrations much higher than guideline levels might thus have potential health risks to the hotel workers, and technical and management measures should be taken to lower their exposure of radon through inhalation.

Risk evaluation and control strategies for indoor radon: a brief discussion

International Nuclear Information System (INIS)

Nero, A.V. Jr.

1994-01-01

Average risks of death estimated for radon are larger than those for many exposures in the outdoor environment, but similar to some in industrial settings. However, the indoor environment differs in regard to cost, benefit, responsibility, and distribution of risks from the outdoor and occupational settings, where frameworks for setting risk-limiting objectives and strategies have already been developed substantially. This indicates the need to develop a conceptual framework for evaluating risks in the indoor environment, within which the objectives of radon control strategies can be sensibly chosen. Nevertheless, the range of estimated radon risks and of recent radon control strategies suggest near-term elements of any strategy, i.e. accurate and effective public information, as well as reliable monitoring and control capabilities, and a focus on areas where most high residential levels occur. Developing a conceptual framework for evaluating indoor risks will permit the formulation of suitable aims on average indoor exposures and lower exposure situations. (author)

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

International Nuclear Information System (INIS)

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

2016-01-01

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

Indoor radon distribution of subway stations in a Korean major city

International Nuclear Information System (INIS)

Yoon, Seokwon; Chang, Byung-Uck; Kim, Yongjae; Byun, Jong-In; Yun, Ju-Yong

2010-01-01

The overall survey on indoor radon concentration was conducted at all subway stations in a major city, Daejeon in the central part of Korea. It was quarterly performed from September 2007 to August 2008. The annual arithmetic mean of indoor radon concentration of all the stations was 34.1 ± 14.7 Bq m -3 , and the range of values was from 9.4 to 98.2 Bq m -3 . The radon concentrations in groundwater (average 31.0 ± 0.8 Bq m -3 ) were not significantly high in most stations, but the concentration (177.9 ± 2.3 Bq L -1 ) of one station was over the level of 148 Bq L -1 in drinking water proposed by U.S. EPA. Based on indoor survey results, the approximate average of the annual effective dose by radon inhalation to the employees and passengers were 0.24 mSv y -1 , and 0.02 mSv y -1 , respectively. Although the effective dose based on the UNSCEAR report was potentially estimated, for more accurate assessment, the additional survey on the influence by indoor radon will be necessary.

Indoor radon distribution of subway stations in a Korean major city

Energy Technology Data Exchange (ETDEWEB)

Yoon, Seokwon [Korea Institute of Nuclear Safety, Gwahak-ro 34, Yuseong-gu, 305-338 Daejeon (Korea, Republic of); Chang, Byung-Uck, E-mail: hafadai@kins.re.k [Korea Institute of Nuclear Safety, Gwahak-ro 34, Yuseong-gu, 305-338 Daejeon (Korea, Republic of); University of Science and Technology, Gwahak-ro 113, Yuseong-gu, 305-333 Daejeon (Korea, Republic of); Kim, Yongjae [Korea Institute of Nuclear Safety, Gwahak-ro 34, Yuseong-gu, 305-338 Daejeon (Korea, Republic of); Byun, Jong-In [University of Science and Technology, Gwahak-ro 113, Yuseong-gu, 305-333 Daejeon (Korea, Republic of); Yun, Ju-Yong [Korea Institute of Nuclear Safety, Gwahak-ro 34, Yuseong-gu, 305-338 Daejeon (Korea, Republic of); University of Science and Technology, Gwahak-ro 113, Yuseong-gu, 305-333 Daejeon (Korea, Republic of)

2010-04-15

The overall survey on indoor radon concentration was conducted at all subway stations in a major city, Daejeon in the central part of Korea. It was quarterly performed from September 2007 to August 2008. The annual arithmetic mean of indoor radon concentration of all the stations was 34.1 +- 14.7 Bq m{sup -3}, and the range of values was from 9.4 to 98.2 Bq m{sup -3}. The radon concentrations in groundwater (average 31.0 +- 0.8 Bq m{sup -3}) were not significantly high in most stations, but the concentration (177.9 +- 2.3 Bq L{sup -1}) of one station was over the level of 148 Bq L{sup -1} in drinking water proposed by U.S. EPA. Based on indoor survey results, the approximate average of the annual effective dose by radon inhalation to the employees and passengers were 0.24 mSv y{sup -1}, and 0.02 mSv y{sup -1}, respectively. Although the effective dose based on the UNSCEAR report was potentially estimated, for more accurate assessment, the additional survey on the influence by indoor radon will be necessary.

Predictors of Indoor Radon Concentrations in Pennsylvania, 1989–2013

Science.gov (United States)

Casey, Joan A.; Ogburn, Elizabeth L.; Rasmussen, Sara G.; Irving, Jennifer K.; Pollak, Jonathan; Locke, Paul A.

2015-01-01

Background Radon is the second-leading cause of lung cancer worldwide. Most indoor exposure occurs by diffusion of soil gas. Radon is also found in well water, natural gas, and ambient air. Pennsylvania has high indoor radon concentrations; buildings are often tested during real estate transactions, with results reported to the Department of Environmental Protection (PADEP). Objectives We evaluated predictors of indoor radon concentrations. Methods Using first-floor and basement indoor radon results reported to the PADEP between 1987 and 2013, we evaluated associations of radon concentrations (natural log transformed) with geology, water source, building characteristics, season, weather, community socioeconomic status, community type, and unconventional natural gas development measures based on drilled and producing wells. Results Primary analysis included 866,735 first measurements by building, with the large majority from homes. The geologic rock layer on which the building sat was strongly associated with radon concentration (e.g., Axemann Formation, median = 365 Bq/m3, IQR = 167–679 vs. Stockton Formation, median = 93 Bq/m3, IQR = 52–178). In adjusted analysis, buildings using well water had 21% higher concentrations (β = 0.191, 95% CI: 0.184, 0.198). Buildings in cities (vs. townships) had lower concentrations (β = –0.323, 95% CI: –0.333, –0.314). When we included multiple tests per building, concentrations declined with repeated measurements over time. Between 2005 and 2013, 7,469 unconventional wells were drilled in Pennsylvania. Basement radon concentrations fluctuated between 1987 and 2003, but began an upward trend from 2004 to 2012 in all county categories (p Pennsylvania, 1989–2013. Environ Health Perspect 123:1130–1137; http://dx.doi.org/10.1289/ehp.1409014 PMID:25856050

Measurement of indoor radon concentration by CR-39 track detector

International Nuclear Information System (INIS)

Yamamoto, Masayoshi; Yoneda, Shigeru; Nakanishi, Takashi.

1990-01-01

A convenient and cheap method for measuring indoor radon ( 222 Rn) concentration with a CR-39 track detector is described. The detector consisted of two sheets of CR-39 enclosed separately in two plastic pots : one covered by a filter (cup method) and another no covering (bare method). The bare method was used here to supplement the cup method. To compare with the result of the CR-39 detector, alpha-ray spectrometry was carried out with a Si(Au) detector in a controlled radon exposure chamber. Indoor radon concentration measured in 133 houses in several districts of Ishikawa Prefecture have been found to range from 6 Bq/m 3 to as high as 113 Bq/m 3 with a median value of 24 Bq/m 3 . The problems to measure indoor radon concentration using the CR-39 detector are also discussed with emphasis on the position of setting the detector in the room and the possible thoron contribution to the detector. (author)

Estimating lung cancer risks of indoor radon: applications for prevention

International Nuclear Information System (INIS)

Klotz, J.B.

1986-01-01

The epidemiologic evidence for a serious lung cancer hazard from radon exposure is very strong, and cumulative exposures accrued in residences may frequently overlap those accrued in underground miners. However, many uncertainties exist in extrapolating from mining to indoor risks because of differences in the populations, in radon exposure variables, and in other exposures. Risks are also considered for indoor radon exposures outside the home. There is already suggestive evidence of an association of lung cancer with radon levels in community settings, and several large-scale investigations are in progress. Some important questions regarding quantifying risk may not be approached, however; some further research needs are outlined including development of techniques for preventing or postponing lung cancer in individuals previously exposed to high radon levels. 31 references, 2 tables

Daily variation of the radon concentration indoors and outdoors and the influence of meteorological parameters

International Nuclear Information System (INIS)

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

1994-01-01

Series of continuous radon measurements in the open atmosphere and in a dwelling, including the parallel measurement of meteorological parameters, were performed over a period of several weeks. The radon concentration in indoor and outdoor air depends on meteorological conditions. In the open atmosphere the radon concentration varies between 1 and 100 Bq m -3 , depending on weather conditions and time of day. During time periods of low turbulent air exchange (high pressure weather with clear night sky), especially in the night and early morning hours (night inversion layer), the diurnal variation of the radon concentration showed a pronounced maximum. Cloudy and windy weather conditions yield a small diurnal variation of the radon concentration. Indoors, the average level and the diurnal variation of the indoor radon concentration is also influenced by meteorological conditions. The measurements are consistent with a dependence of indoor radon concentrations on indoor-outdoor pressure differences. 11 refs., 4 figs

Correlation of indoor radon levels with physical properties of local soil in Khammam district, Andhra Pradesh, India

International Nuclear Information System (INIS)

Sreenivasa Reddy, B.; Bhaskar Reddy, G.; Sreenath Reddy, M.; Gopal Reddy, Ch; Yadagiri Reddy, P.; Rama Reddy, K.

2006-01-01

Indoor radon contributes significantly to the total radiation exposure caused to human beings. As might be expected, the physical characteristics of soil play key roles in determining the radon concentration in nearby buildings. The physical characteristics of soil, such as density, specific gravity and porosity in the vicinity of the dwellings of Khammam district, Andhra Pradesh, India, have been determined using core cutter and specific gravity bottle. In the present paper, these parameters are correlated with the average indoor radon levels estimated for a year using solid state nuclear track detectors. (author)

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)

Indoor radon concentrations and radon doses at three districts of Ankara, Turkey and raising public awareness on the issue

International Nuclear Information System (INIS)

Mehmet Kildir; Inci Goekmen; Ali Goekmen

2016-01-01

Indoor radon concentrations at METU, CIGDEM and DOSTLAR in Ankara were measured using electrets. The statistical analysis of the data indicated a lognormal distribution of radon concentrations, with no significant difference between CIGDEM and DOSTLAR with geometric means of GM = 87.5 and 54.5 Bq m -3 , respectively. Radon concentrations did not change seasonally at CIGDEM which contain modern buildings, but at the slum district DOSTLAR, with poor insulation of houses a seasonal variation was observed. Annual effective radon doses were estimated (0.4-8.4 mSv). Public awareness about indoor radon was raised. (author)

Measurements of indoor radon concentration in italian red cross workplaces: preliminary results

International Nuclear Information System (INIS)

Fontana, C.; Musumeci, R.G.; Valeriani, F.; Tonnarini, S.; Trevisi, R.

2002-01-01

In August 2000 in Italy the D.Lgs.241/00 law was passed to implement the 96/29 Euratom Directive (BSS Directive, EC 1996). D.Lgs.241/00 states that workers cannot be exposed to decay products of radon, thoron and gamma radiation at a level higher than action level. The law became effective January 1, 2001. Italian action level of 500 Bq/m3 is the annual average indoor radon concentration. Work activities in zones with greater probability of high indoor radon concentration have to be identified. According to the law, a Commission must establish criteria for clarifying areas at risk. The actual work of classification is then done by the regions. A three year time period was given to define areas at risk. As the normative still must be completed, the Italian Red Cross and the Italian National Institute for Occupational Prevention and Safety initiated this study both because the Red Cross has always been sensitive to health problems and also to offer the Commission further experimental data regarding radon in Italy

An indoor radon survey of the X-ray rooms of Mexico City hospitals

Energy Technology Data Exchange (ETDEWEB)

Juarez, Faustino [Facultad de Ciencias, Universidad Autonoma del Estado de Mexico, Instituto Literario No. 100. Estado de Mexico, 50000, Mexico. Instituto de Geofisica, Universidad Nacional Autonoma de Mexico, Circuito (Mexico); Reyes, Pedro G. [Facultad de Ciencias, Universidad Autonoma del Estado de Mexico, Instituto Literario No. 100. Estado de Mexico, 50000 (Mexico); Espinosa, Guillermo [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Circuito Exterior Ciudad Universitaria, Mexico D.F. Cp.04510 (Mexico)

2013-07-03

This paper presents the results of measurements of indoor radon concentrations in the X-ray rooms of a selection of hospitals in the metropolitan area of Mexico City. The metropolitan area of Mexico City is Mexico's largest metropolitan area by population; the number of patients requiring the use of X-rays is also the highest. An understanding of indoor radon concentrations in X-ray rooms is necessary for the estimation of the radiological risk to which patients, radiologists and medical technicians are exposed. The indoor radon concentrations were monitored for a period of six months using nuclear track detectors (NTD) consisting of a closed-end cup system with CR-39 (Lantrack Registered-Sign ) polycarbonate as detector material. The indoor radon concentrations were found to be between 75 and 170 Bq m{sup -3}, below the USEPA-recommended indoor radon action level for working places of 400 Bq m{sup -3}. It is hoped that the results of this study will contribute to the establishment of recommended action levels by the Mexican regulatory authorities responsible for nuclear safety.

The impacts of balanced and exhaust mechanical ventilation on indoor radon

International Nuclear Information System (INIS)

Fisk, W.J.; Mowris, R.J.

1987-02-01

Models for estimating radon entry rates, indoor radon concentrations, and ventilation rates in houses with a basement or a vented crawl-space and ventilated by natural infiltration, mechanical exhaust ventilation, or balanced mechanical ventilation are described. Simulations are performed for a range of soil and housing characteristics using hourly weather data for the heating season in Spokane, WA. For a house with a basement, we show that any ventilation technique should be acceptable when the soil permeability is less than approximately 10 -12 m 2 . However, exhaust ventilation leads to substantially higher indoor radon concentrations than infiltration or balanced ventilation with the same average air exchange rate when the soil permeability is 10 -10 m 2 or greater. For houses with a crawl-space, indoor radon concentrations are lowest with balanced ventilation, intermediate with exhaust ventilation, and highest with infiltration

Indoor radon concentration forecasting in South Tyrol

International Nuclear Information System (INIS)

Verdi, L.; Weber, A.; Stoppa, G.

2004-01-01

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

Indoor radon concentration measurement in the dwellings of Al-Jauf region of Saudi Arabia

International Nuclear Information System (INIS)

Al-Jarallah, M. I.; Fazal ur, Rehman

2006-01-01

Indoor radon concentration measurement in the dwellings of Al-Jauf region of Saudi Arabia was carried out using passive radon dosemeters. The objective of this radon survey was to obtain representative indoor radon data of Al-Jauf region. The study is a continuation of radon survey in main cities of Saudi Arabia which constitutes a baseline for Saudi Arabia in the Radon World Atlas. A total of 318 passive radon dosemeters were distributed randomly in the region and placed for a period of 1 y starting from April 2004 to April 2005. The results of indoor radon concentration measurement in 136 dwellings distributed in Al-Jauf region are presented. The remaining dosemeters were lost in the dwellings or mishandled. The results showed that the average, minimum, maximum radon concentrations and standard deviation were 35, 7, 168 and 30 Bq m -3 , respectively. Geometric mean and geometric standard deviation of the radon distribution were found to be 28 and 1.83, respectively. (authors)

Indoor radon in houses built on gravel and sand deposits in southern Finland

Directory of Open Access Journals (Sweden)

Hutri, K.-L.

1993-06-01

Full Text Available Studies by the Finnish Centre for Radiation and Nuclear Safety (STUK have shown that, in Finland, indoor radon concentrations are almost twice as high in houses built on sand or gravel as in houses built on other soil types. The aim of this study was to assess the radon risk on eskers, ice-marginal formations, and other gravel and sand deposits on the basis of factors that can be determined from geological maps. Altogether, 514 houses built on gravel and sand deposits were selected for the study from the indoor radon database of STUK. Several geological parameters were determined. Empirical statistical models were used to assess the significance of factors affecting indoor radon in glaciofluvial deposits and the sand-dominant littoral deposits occurring in association with them. A relationship was found between increased indoor radon concentrations and the location of a house on a steep-sided esker, in the southeastern rapakivi granite area and on the upper slope or top of an esker. The steepness of the slope also increased the radon concentration in houses on steep-sided eskers. The effect of the topographic features is due to subterranean air-flows. As estimated from the very sparse till sampling, the elevated uranium concentration increased the indoor radon concentration only in houses built on littoral deposits around eskers and ice-marginal formations.

Radon gas sampler for indoor and soil measurements and its applications

International Nuclear Information System (INIS)

Azimi-Garakani, D.; Flores, B.; Piermattei, S.; Susanna, A.F.; Seidel, J.L.; Tommasino, L.; Torri, G.

1988-01-01

A national large scale survey of indoor radon (based on an optimised sampling strategy) is needed in Italy to obtain average population dose for use in epidemiological studies. Since in the great majority of cases, one of the most important radon sources is the soil and rock beneath the houses, it would be interesting to combine this survey with measurements of bed-soil radon. With these objectives in mind, a new radon monitor device has been developed consisting of two etched track detectors enclosed in a heat-sealed polyethylene bag. When compared with existing techniques, this radon gas sampler presents several advantages for both indoor and outdoor measurements. As a pilot project, radon gas measurements have been carried out in hundreds of different sites and for several locations; measurements have been made for different years. Typical houses with relatively high radon concentrations have also been thoroughly investigated. (author)

Long term indoor radon measurements in the pelletron laboratory at the UNAM physics institute

International Nuclear Information System (INIS)

Espinosa, G.; Golzarri, J. I.; Lopez, K.; Rickards, J.

2011-01-01

The results of six months of continuous measurement of the indoor radon concentration levels in the building where the Physics Institute 3 MV Pelletron particle accelerator is located are presented. This study has three major objectives: a) to know the actual values of the levels of indoor radon in this installation, where personnel spend many hours and sometimes days; b) assess the radiological risk from radon inhalation for personnel working permanently in the laboratory, as well as incidental users; and c) establish, if necessary, time limits for continuous permanence on the location for indoor radon exposure. Passive nuclear track detectors and dynamic systems were employed, covering six months (August, 2009 to January, 2010). For the calculation of internal dose the Radon Individual Dose Calculator was used. The results indicate that the indoor radon levels are below the US EPA recommended levels (400 Bq/m 3 ) in workplaces. The measurements help to establish levels for workplaces in Mexico. (Author)

Factors affecting yearly variations of indoor radon concentrations

International Nuclear Information System (INIS)

Steck, D.J.; Baynes, S.A.

1996-01-01

Since indoor radon exposures take place over many years while radon measurement periods are shorter, we are studying the yearly variation of indoor radon concentrations in approximately 100 houses located throughout Minnesota. Most houses were initially measured for one or more years in the late 1980's and for 5 consecutive years starting in 1990. Two houses have been monitored for 12 y. Each year, two alpha track detectors were placed on the two lowest livable levels. The year-to-year variations averaged about 35% (corrected for instrumental uncertainties) in both basements and first floors. The minimum observed variation was 5% and the maximum was 130%. Some homes have shown substantial variation associated with Structural modifications. While most homes show no obvious systematic trends, a few houses have shown temporal trends that may be associated with aging or climate. We are studying possible correlation between year-to-year radon variation, climatic variables (yearly-average and seasonal such as heating/cooling degree days, precipitation, soil moisture), and structural changes

Indoor Radon Exposure in Italian Schools

Directory of Open Access Journals (Sweden)

Antonio Azara

2018-04-01

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

Mortality and indoor radon daughter concentrations in 13 Canadian cities

International Nuclear Information System (INIS)

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

1980-01-01

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

Influence of ventilation strategies on indoor radon concentrations based on a semiempirical model for Florida-style houses

International Nuclear Information System (INIS)

Hintenlang, D.E.; Al-Ahmady, K.K.

1994-01-01

Measurements in a full-scale experimental facility are used to benchmark a semiempirical model for predicting indoor radon concentrations for Florida-style houses built using slab-on-grade construction. The model is developed to provide time-averaged indoor radon concentrations from quantitative relationships between the time-dependent radon entry and elimination mechanisms that have been demonstrated to be important for this style of residential construction. The model successfully predicts indoor radon concentrations in the research structure for several pressure and ventilation conditions. Parametric studies using the model illustrate how different ventilation strategies affect indoor radon concentrations. It is demonstrated that increasing house ventilation rates by increasing the effective leakage area of the house shell does not reduce indoor radon concentrations as effectively as increasing house ventilation rates by controlled duct ventilation associated with the heating, ventilating, and air conditioning system. The latter strategy provides the potential to minimize indoor radon concentrations while providing positive control over the quality of infiltration air. 9 refs., 5 figs

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

Science.gov (United States)

Gross, Eliza L.

2017-05-11

Physiographic Province, had a median radon concentration greater than the EPA proposed AMCL of 4,000 pCi/L. Median concentrations of radon in groundwater and indoor air were determined to differ significantly among the geologic units (Kruskal-Wallis test, significance probability, ptool for property owners to decide whether to test for radon concentrations at specific locations. Instead, the data and maps are meant to promote awareness regarding potential radon exposure in Pennsylvania and to point out data gaps that exist throughout the State.

Radon testing in schools in New York State: a 20-year summary

International Nuclear Information System (INIS)

Kitto, Michael

2014-01-01

For nearly 20 years the Department of Health has conducted programs to assist in the measurement and reduction of indoor radon concentrations in 186 schools located primarily in Zone 1 areas of New York State. Although many schools had few or no rooms containing radon above 148 Bq/m 3 , some rooms had >740 Bq/m 3 and remediation techniques were utilized to reduce exposure. Short-term radon measurements in the schools showed little correlation to basement and first-floor radon results from single-family homes in the towns. - Highlights: • Relatively few schools in New York State have been tested for indoor radon. • We provide a summary of radon-testing results for measured schools. • The radon potential in schools is often less than in local houses. • Short-term measurement results exceeded their long-term counterparts in nearly every case

Predictions of lung cancer based on county averages for indoor radon versus the historic incidence of regional lung cancer

International Nuclear Information System (INIS)

Mose, D.G.; Chrosniak, C.E.; Mushrush, G.W.

1992-01-01

After a decade of effort to determine the health risk associated with indoor radon, the efforts of the US Environmental Protection Agency have prevailed in the US, and 4 pCi/1 is commonly used as an Action Level. Proposals by other groups supporting lower or higher Action Levels have failed, largely due to paucity of information supporting any particular level of indoor radon. The authors' studies have compared indoor radon for zip code and county size areas with parameters such as geology, precipitation and home construction. Their attempts to verify the relative levels of lung cancer using US-EPA estimates of radon-vs-cancer have not been supportive of the EPA risk estimates. In general, when they compare the number of lung cancer cases in particular geological or geographical areas with the indoor radon levels in that area, they find the EPA predicted number of lung cancer cases to exceed the total number of lung cancer cases from all causes. Comparisons show a correlation between the incidence of lung cancer and indoor radon, but the level of risk is about 1/10 that proposed by the US-EPA. Evidently the assumptions used in their studies are flawed. Even though they find lower risk estimates using many counties in several states, fundamental flaws must be present in this type of investigation. Care must be taken in presenting health risks to the general population in cases, such as in indoor radon, where field data do not support risk estimates obtained by other means

Contribution to the relation between volume activity of soil and indoor radon

International Nuclear Information System (INIS)

Mojzes, A.

1999-01-01

There were carried out some repeated manual measurements of volume activity of radon-222 (VAR) in both soil air of subsoil and also indoor air of buildings in two different areas in Bratislava. All measurements were done with a portable scintillation detector based on exchangeable Lucas cells. The measurements were repeated in different day and year intervals. There were repeated 259 measurements of volume activity of radon-222 in soil air with the average valuer 11.95 kBq/m 3 and the standard deviation 1.53 kBq/m 3 in the subsoil of the one-story house and 597 measurements of VAR in soil air of the subsoil of the second study building with the average 9.44 kBq/m 3 and the standard deviation 3.08 kBq/m 3 . Presented results of measurement of radon-222 volume activity in both soil and indoor air demonstrate that also in case of low radon concentrations in soil air of geological basement the level of radon in indoor air could be considerably high. It depends mainly on used technology of laying building foundations, on the distance from subsoil and on regime of ventilation. In case of older buildings the ventilation is very effective way to reduce the presence of radon in indoor air. (author)

The distribution of indoor radon in Transylvania (Romania) - influence of the natural and anthropogenic factors

Science.gov (United States)

Cucos Dinu, Alexandra; Baciu, Calin; Dicu, Tiberius; Papp, Botond; Moldovan, Mircea; Bety Burghele, Denissa; Tenter, Ancuta; Szacsvai, Kinga

2017-04-01

Exposure to radon in homes and workplaces is now recognized as the most important natural factor in causing lung cancer. Radon activity is usually higher in buildings than in the outside atmosphere, as it may be released from building materials and soil beneath the constructions, and the concentration builds-up indoor, due to the low air renewal rates. Indoor radon levels can vary from one to multiple orders of magnitude over time and space, as it depends on several natural and anthropogenic factors, such us the radon concentration in soil under the construction, the weather conditions, the degree of containment in the areas where individuals are exposed, building materials, outside air, tap water and even city gas, the architecture, equipment (chimney, mechanical ventilation systems, etc.), the environmental parameters of the building (temperature, pressure, etc.), and on the occupants' lifestyle. The study presents the distribution of indoor radon in Transylvania, Romania, together with the measurements of radon in soil and soil water. Indoor radon measurements were performed by using CR-39 track detectors exposed for 3 months on ground-floor level of dwellings, according to the NRPB Measurement Protocol. Radon concentrations in soil and water were measured using the LUK3C device. A complete map was plotted at the date, based on 3300 indoor radon measurements, covering an area of about 42% of the Romanian territory. The indoor radon concentrations ranged from 5 to 3287 Bq m-3, with an updated preliminary arithmetic mean of 179 Bq m-3, and a geometric mean of 122 Bq m-3. In about 11% of the investigated grid cells the indoor radon concentrations exceed the threshold of 300 Bq m-3. The soil gas radon concentration varies from 0.8 to 169 kBq m-3, with a geometric mean of 26 kBq m-3. For water samples, the results show radon concentrations within the range of 0.3 - 352.2 kBq m-3, with a geometric mean of 7.7 Bq L-1. A weak correlation between the three sets of values

The application of air pressure difference in reducing indoor radon concentration

International Nuclear Information System (INIS)

Leung, J.K.C.; Tso, M.Y.W.

2000-01-01

In densely populated tropical cities like Hong Kong, people usually live and work inside high-rise buildings. And because of the hot and humid climate, air conditioning systems are used throughout the year, particularly in commercial buildings. Previous territory-wide surveys have shown that over 10% of commercial buildings in Hong Kong have indoor radon concentrations above 200 Bq m -3 . Since the major source of indoor radon in high-rise buildings is the building materials, increasing ventilation and applying radon barriers on wall surfaces seem to be the only ways to reduce the indoor radon concentration. But it was noted that the ventilation rate the many commercial buildings are not efficient enough to remove the radon because of various reasons such as energy saving, lack of maintenance, etc. In this study, radon mitigation was achieved by reducing the rate of radon exhaled from the building materials. A special laboratory, which has the capability of simulating any meteorological conditions that could be faced by high-rise buildings in Hong Kong, was built. The reduction of radon exhalation rate by applying pressure difference and temperature difference across walls was studied in the laboratory. This paper summarizes the results and tactics for applying pressure difference in existing commercial buildings. A new technique of reducing radon exhalation rate in new buildings by depressurizing the interior of walls was also developed. Tunnels can be embedded in the concrete walls of new buildings during construction. By using simple vacuum pumps, radon exhalation rate from the walls can be reduced significantly by depressurizing the tunnels. The feasibility and applicability of the technique is presented in this paper. (author)

Indoor radon measurements and radon prognosis for eastern Uusimaa. Askola, Lapinjaervi, Liljendal, Loviisa, Myrskylae, Maentsaelae, Maentsaelae, Pernaja, Pornainen, Porvoo, Porvoon mlk, Pukkila, Ruotsinpyhtaeae and Sipoo

International Nuclear Information System (INIS)

Voutilainen, A.; Maekelaeinen, I.

1995-02-01

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 the study about 2400 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 form maps and questionnaires. An empirical statistical model, the adjusted indoor radon measurement and geological data were used to assess the radon risk form soil and bedrock in different areas. (15 refs., 19 figs., 9 tabs.)

Mitigation of houses with extremely high indoor radon concentrations

International Nuclear Information System (INIS)

Jiranek, M.; Neznal, M.

2006-01-01

Full text of publication follows: The paper reports on the experience of the Czech Technical University in dealing with mitigation of houses in which unusually high indoor radon concentrations were found. The whole process of remediation is illustrated by example of an old single-family house that was built in the area formed by highly permeable soils with high radon content in the soil air. T he house has a small cellar located under 1/5 of the ground floor area. Two types of floors, i.e. timber floors and cracked concrete slabs were found in the house. As a result of extremely high radon concentration in the sub-floor region (up to 600 kBq/m 3 ) and leaky structures in contact with soil, radon concentrations around 100 kBq/m 3 in the cellar and up to 60 kBq/m 3 in the living rooms on the ground floor were measured prior to mitigation. Mitigation measures that were carried out in the house consist of reconstruction of timber floors and installation of active soil depressurization. Timber floors were replaced with concrete slab fitted with damp proof membrane, thermal insulation and floor covering. The soil depressurization system was made up of two sections. The first section is composed of the network of perforated pipes inserted in the drainage layer placed under the new floors and four perforated tubes drilled under the existing floors. The soil air from this section is extracted by means of a roof fan installed at the top of the vertical exhaust pipe running inside the living space and terminating above the roof. The second section was designed to withdraw by means of a small fan radon-laden air from the filling in the floor above the cellar and from perforated tubes drilled into the sub-floor region under the rooms adjacent to the cellar. It serves also for the active ventilation of the cellar. Pressure, temperature and radon concentration sensors were installed into the drainage layer during the reconstruction of floors to record variations in these

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)

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.)

Influences on indoor radon concentrations in Riyadh, Saudi Arabia

International Nuclear Information System (INIS)

Alghamdi, Abdulrahman S.; Aleissa, Khalid A.

2014-01-01

The influences on indoor radon concentrations in Riyadh, Saudi Arabia survey was carried out for 786 dwellings. The measurements were obtained by using a passive integrating ionization system with an E-Perm ® Electret ion chamber. Radon levels ranged from 1 to 195 Bq m −3 , with a mean value of 24.68 Bq m −3 , the geometric mean and the geometric standard deviation are 21 and 2 respectively. 98.5% of the results were below the action level recommended by WHO of 100 Bq.m −3 . The results were found to vary substantially due to types of houses and rooms, ventilation, seasons and building materials. Radon concentrations were higher in houses with no ventilation systems, and central air conditioners, and were relatively lower in well ventilated houses with red bricks and water air conditioners. - Highlights: • Limited information about indoor radon in Riyadh. • Several factors influence Radon level were investigated in 786 dwellings in Riyadh over one year. • Some results are over the action level and are advised to improve their ventilation systems

An electrical circuit model for simulation of indoor radon concentration.

Science.gov (United States)

Musavi Nasab, S M; Negarestani, A

2013-01-01

In this study, a new model based on electric circuit theory was introduced to simulate the behaviour of indoor radon concentration. In this model, a voltage source simulates radon generation in walls, conductivity simulates migration through walls and voltage across a capacitor simulates radon concentration in a room. This simulation considers migration of radon through walls by diffusion mechanism in one-dimensional geometry. Data reported in a typical Greek house were employed to examine the application of this technique of simulation to the behaviour of radon.

Correlations of soil-gas and indoor radon with geology in glacially derived soils of the northern Great Plains

International Nuclear Information System (INIS)

Schumann, R.R.; Owen, D.E.; Peake, R.T.; Schmidt, K.M.

1990-01-01

This paper reports that a higher percentage of homes in parts of the northern Great Plains underlain by soils derived from continental glacial deposits have elevated indoor radon levels (greater than 4 pCi/L) than any other area in the country. Soil-gas radon concentrations, surface radioactivity, indoor radon levels, and soil characteristics were studied in areas underlain by glacially-derived soils in North Dakota and Minnesota to examine the factors responsible for these elevated levels. Clay-rich till soils in North Dakota have generally higher soil-gas radon levels, and correspondingly higher indoor radon levels, than the sandy till soils common to west-central Minnesota. Although the proportions of homes with indoor radon levels greater than 4 pCi/L are similar in both areas, relatively few homes underlain by sandy tills have screening indoor radon levels greater than 20 pCi/L, whereas a relatively large proportion of homes underlain by clayey tills have screening indoor radon levels exceeding 20 pCi/L. The higher radon levels in North Dakota are likely due to enhanced emanation from the smaller grains and to relatively higher soil radium concentrations in the clay-rich soils, whereas the generally higher permeability of the sandy till soils in Minnesota allows soil gas to be drawn into structures from a larger source volume, increasing indoor radon levels in these areas

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

Indoor radon levels and inhalation doses in dwellings near the some sites of Himachal Pradesh, India

International Nuclear Information System (INIS)

Bajwa, B.S.; Singh, S.; Virk, H.S.

2005-01-01

In view of the fact that radon and its daughters are a major source of natural radiation exposure, the measurement of radon concentration levels in dwellings has assumed ever-increasing importance. Keeping this in view, the indoor radon level measurements were carried out in the dwellings of different villages known to be located in the vicinity of uranium-mineralized pockets of Hamirpur district, Himachal Pradesh. Track-etch technique, a passive method using the Solid State Nuclear Track Detectors (SSNTDs), LR-115 type II, was utilized for these measurements. An attempt has been made to assess the levels of the indoor radon in the dwellings and inhalation dose rates of the population living in these villages. The radon concentrations were found to be varying with seasonal changes, building materials and mode of construction of houses. The radon concentrations were found to be higher in houses made from local sandstone and with mud floor in comparison to the houses having cemented brick floors. The annual indoor radon concentration and thus annual effective dose in most of the dwellings of these villages is certainly quite higher and even in some of the dwellings it even exceeds the upper limit of the proposed action level of ICRP, 1993. The inhalation dose rates in dwellings of these villages located in the vicinity of uranium mineralized pockets of Hamirpur district, Himachal Pradesh have been found to be quite higher than dose rate in the dwellings in the Amritsar city, Punjab, which is located in a completely uranium free zone. The radon survey in the dwellings of these villages has also been carried out using the Alpha-Guard technique, which is based on the pulse ionization chamber. The indoor radon concentration levels measured using the active technique of Alpha Guard have been found to be quite different from those measured in these dwellings by the passive technique of SSNTDs; indicating the importance of the SSNTDs in the long-term integrated measurement

Large-scale radon hazard evaluation in the Oslofjord region of Norway utilizing indoor radon concentrations, airborne gamma ray spectrometry and geological mapping

International Nuclear Information System (INIS)

Smethurst, Mark Andrew; Strand, Terje; Sundal, Aud Venke; Rudjord, Anne Liv

2008-01-01

We test whether airborne gamma ray spectrometer measurements can be used to estimate levels of radon hazard in the Oslofjord region of Norway. We compile 43,000 line kilometres of gamma ray spectrometer data from 8 airborne surveys covering 10,000 km 2 and compare them with 6326 indoor radon measurements. We find a clear spatial correlation between areas with elevated concentrations of uranium daughters in the near surface of the ground and regions with high incidence of elevated radon concentrations in dwellings. This correlation permits cautious use of the airborne data in radon hazard evaluation where direct measurements of indoor radon concentrations are few or absent. In radon hazard evaluation there is a natural synergy between the mapping of radon in indoor air, bedrock and drift geology mapping and airborne gamma ray surveying. We produce radon hazard forecast maps for the Oslofjord region based on a spatial union of hazard indicators from all four of these data sources. Indication of elevated radon hazard in any one of the data sets leads to the classification of a region as having an elevated radon hazard potential. This approach is inclusive in nature and we find that the majority of actual radon hazards lie in the assumed elevated risk regions

On the behaviour of radon in indoor air

International Nuclear Information System (INIS)

Lehtimaeki, M.; Kivistoe, T.

1983-01-01

In this work the behaviour of radon in indoor air has been studied. A simple mathematical model is presented to describe the variations in radon concentration in case of a periodic ventilation. This model has been tested with the aid of long-term measurements in two office buildings, in a large shipyard hall, and in a dwelling. The variations predicted by the simple model were observed in all buildings studied. It seems even possible that if the mixing of radon in the building is effective, the radon measurements can be used in estimating the infiltration rates. The measurement in one of the office buildings, however, indicated that the mixing of radon in a many-storied building can be extremely incomplete. The measurements also indicate that the soil can be a very important source of radon. (orig.) [de

A comparative study of indoor radon concentrations between dwellings and schools

International Nuclear Information System (INIS)

Kapdan, E.; Altinsoy, N.

2012-01-01

The aim of this study is to determine the relationship of radon concentrations between dwellings and the schools located in the same regions and to obtain related indoor average radon concentration dwelling–school correction factor for similar locations. The research has been carried out by determining indoor radon concentrations at schools and dwellings located at the same districts in the selected two separate research fields called The Former Adapazari region and The New Adapazari region in the city of Adapazari using a total of 81 Cr-39 passive radon detectors for 75 days. The average radon concentrations have been determined for the dwellings and the schools in 15 districts of the Former Adapazari region as 59.9 Bq m −3 and 57.1 Bq m −3 , respectively. The results in 4 districts of the New Adapazari region were 63.5 Bq m −3 for the dwellings and 61.0 Bq m −3 for the schools. Moreover, the annual effective doses were calculated as 1.33 mSv/y and 1.41 mSv/y for the dwellings of Former Adapazari and New Adapazari, respectively. It was seen that the doses received in the dwellings are about four times the doses received in the schools. The indoor radon concentration dwelling–school correction factor was found to be 1.04±0.01 for the research area.

Development and distribution of radon risk maps in New York State

International Nuclear Information System (INIS)

Kitto, M.E.; Kunz, C.O.; New York State Univ., Albany, NY; Green, J.G.

2001-01-01

Radon maps for each county in New York State have been developed on the township level indicating the percent of homes with ≥ 148 Bq/m 3 (4 pCi/l) in the indoor air of the basement and living area. Estimates are based on a combination of nearly 45,000 basement-screening measurements and correlations to surficial geology. Many of the towns and cities in the State with the highest average indoor radon concentrations are located on highly-permeable gravelly soils formed during the retreat of the Wisconsinan Glaciation. As many towns (32% of total) had ≤ 5 measurements, a project to obtain additional measurements in high-risk towns produced results comparable to estimates based on correlations to surficial geology. Radon risk maps for each county have been distributed to municipal governments, schools, and professionals in activities related to homes, buildings, and indoor air quality. (author)

A contemporary method for monitoring indoor radon and environmental conditions at a remote test site

International Nuclear Information System (INIS)

Renken, K.J.; Coursin, S.

1996-01-01

A state-of-the-art method for automatically monitoring indoor radon and environmental conditions at a remote test site is described. A Wisconsin home that exhibited elevated radon levels has been installed with automated PC-data acquisition system (PC-DAS) that includes: a laptop PC, a data acquisition cardcage, a commercial data acquisition software program plus sensors to measure radon gas concentrations, differential pressures, indoor air quality and meteorological conditions. The isolated PC-DAS is connected to a PC in a university laboratory via a modem and a communications software package. Experimental data is monitored and saved by the remote PC in real time and then automatically downloaded to the lab computer at selected intervals. An example of the formatted field results is presented and analysed. This documentation of the set-up, the off-the-shelf computer hardware and software, and the procedures should assist investigations requiring flexible remote long-term radon and environmental monitoring. (Author)

Environmental assessment of indoor radon gas exposure health hazards and some of its public risks

International Nuclear Information System (INIS)

Hussein, Abd El-Razik. Z.; Ibrahim, M.Se.; Ragab, M.H.; El-Bukhari, M.S.

2005-01-01

This study examine the relationship between indoor radon gas exposure and the cancer risk and housing characteristics in lung cancer risk houses (CRH) compared to non lung cancer risk houses (NCRH). Mean radon concentrations measured by active method were significantly higher among CRH compared to NCRH, 9:93 pCi/L versus 4.56 pCi/L, respectively. There was no statistically significant diurnal variation as regards radon levels in all examined houses. Indoor radon concentrations show statistically significance in houses with bad ventilation (low air change rate) compared to houses with good ventilation (high air change rate). Houses with floor material of tiles, had statistically significant higher radon concentrations. Neither finishing wall material nor indoor gas source shows statistically significance as regard radon levels. Radon levels > 4 pCi/L (US EPA action level) were statistically significance higher in bed rooms compared levels in living rooms. High radon concentrations were reported in lung cane risk houses and in houses with bad ventilation

A comparative study of indoor radon levels and inhalation dose in some areas of Punjab and Haryana, India

International Nuclear Information System (INIS)

Bajwa, B.S.; Singh, Harmanjit; Singh, Joga; Singh, Surinder

2009-01-01

Indoor radon concentrations have been measured for two consecutive half-year periods in a wide range of dwellings of some regions of Punjab and Haryana states. The objective was to find correlation between the variations of indoor radon levels with the sub-soil, local geology, type of building materials, etc. of the two regions. So keeping this in view the indoor radon measurements have been carried out in the dwellings of different villages around the Tusham ring complex, Bhiwani District, Haryana, known to be composed of acidic volcanics and the associated granites along with some villages of Amritsar District, Punjab. The indoor radon concentration in the dwellings around Tusham (Haryana) have been found to be varying from 120.5±95 to 915.2±233 Bq m -3 , whereas it ranges from 60.0±37 to 235.6±96 Bq m -3 for the dwellings of Punjab. The 222 Rn concentration observed at most of locations particularly around Tusham ring complex region is higher than that of all the villages studied in Punjab region. Local geology including embedded granitic rocks, sub-soil, etc. as well as building materials having higher radioactive content are the major contributors for the higher indoor radon levels observed in the dwelling around Tusham, where few dwellings have higher radon concentrations than the ICRP, 1993 recommendations. The annual effective dose equivalent has also been estimated for each location of the both regions, which has been found to be varying from 1.0 to 17.2 mSv/y. (author)

Variation of annual effective dose due to radon level in indoor air in Marwar region of Rajasthan, India

Energy Technology Data Exchange (ETDEWEB)

Rani, Asha, E-mail: ashasachdeva78@gmail.com [Department of Applied Science, Ferozepur College of Engineering and Technology, Farozshah, Ferozepur-142052, Punjab (India); Mittal, Sudhir, E-mail: sudhirmittal03@gmail.com [Department of Applied Sciences, Punjab Technical University, Jalandhar-144601, Punjab (India); Mehra, Rohit [Department of Physics, Dr. B.R.Ambedkar National Institute of Technology, Jalandhar-144011 (India)

2015-08-28

In the present work, indoor radon and thoron measurements have been carried out from different locations of Jodhpur and Nagaur districts of Northern Rajasthan, India using RAD7, a solid state alpha detector. The radon and thoron concentration in indoor air varies from 8.75 to 61.25 Bq m{sup −3} and 32.7 to 147.2 Bq m{sup −3} with the mean value of 32 and 73 Bq m{sup −3} respectively. The observed indoor radon concentration values are well below the action level recommended by International Commission on Radiological Protection (200-300 Bq m{sup −3}) and Environmental Protection Agency (148 Bq m{sup −3}). The survey reveals that the thoron concentration values in the indoor air are well within the International Commission on Radiological Protection (2005). The calculated total annual effective dose due to radon level in indoor air varies from 0.22 to 1.54 mSv y{sup −1} with the mean value of 0.81 mSv y{sup −1} which is less than even the lower limit of action level 3-10 mSv y{sup −1} recommended by International Commission on Radiological Protection (2005)

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.

Comparative study of short- and long-term indoor radon measurements

Energy Technology Data Exchange (ETDEWEB)

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,; Abdalla, Khalid [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)

2008-08-15

Short-term indoor radon measurements are used widely. Therefore, it is interesting to find out a correlation between these measurements and long-term measurements which reflect a better average radon concentration of individual measurement. To find the correlation between the two measurements of indoor radon concentrations at low radon levels, a study was carried out at 34 locations of King Fahd University of Petroleum and Minerals (KFUPM), Dhahran, Saudi Arabia using active and passive methods. In the short-term active method, a radon gas analyzer (AlphaGUARD) was used for a duration of 24 h in each measurement. In the long-term passive method, CR-39 based radon dosimeters were utilized for a period of 6 months, from January 2006 to June 2006. The short-term active measurements showed that the average, minimum and maximum radon concentrations were 19, 8 and 58Bqm{sup -3}, respectively, with a standard deviation of 8.6Bqm{sup -3}. The long-term passive measurements showed that the average, minimum and maximum radon concentrations were 25, 10 and 67Bqm{sup -3}, respectively, with a standard deviation of 12Bqm{sup -3}. The two measurements showed a poor correlation (R{sup 2}=0.38). The long-term measurements showed on the average higher concentrations by a factor of 1.3.

A passive integrating charcoal detector for indoor radon survey

International Nuclear Information System (INIS)

Lin Lianqing; Ren Tianshan; Li Guiyun

1986-01-01

This paper describes the principle, design, calibration and characteristics of a passive integrating charcoal detector for measuring average radon concentration indoors. The uncertainties of the detector are also evaluated. Under conditions of room temperature at 17 deg C and relative humidity at 30%, the minimum limit of detection is 0.16 pCi/1 for 72 hours exposure. Besides higher sensitivity, the other advantages of this detector are passive, simple and less expensive. It requires no power and makes no noise and gives no interference to daily activities of the residents of dwellings being surveyed. Therefore the detector is suitable for a large-scale survey of radon levels indoors

Indoor-atmospheric radon-related radioactivity affected by a change of ventilation strategy

International Nuclear Information System (INIS)

Kobayashi, Tuneo

2006-01-01

The present author has kept observation for concentrations of atmospheric radon, radon progeny and thoron progeny for several years at the campus of Fukushima Medical University. Accidentally, in the midst of an observation term, i.e., February 2005, the facility management group of the university changed a strategy for the manner of ventilation, probably because of a recession: tidy everyday ventilation of 7:30-24:00 into shortened weekday ventilation of 8:00-21:00 with weekend halts. This change of ventilation manner brought a clear alteration for the concentrations of radon-related natural radioactivity in indoor air. The present paper concerns an investigation of the effect of the ventilation strategy on the indoor-atmospheric radon-related radioactivity. (author)

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.

A risk-based approach to health criteria for radon indoors -report on a WHO initiative

International Nuclear Information System (INIS)

Steinhaeusler, F.

1994-01-01

The World Health Organization (WHO), Regional Office for Europe, organised a meeting of a working group on indoor air quality in Eilat, Israel, from 28 March to 4 April 1993. The aim was to develop a risk-based approach to health criteria for radon indoors. The Group reviewed the latest epidemiological data from occupational and non-occupational radon exposure, animal experiments and dosimetry. The Group issued 14 conclusions and 23 recommendations on radon related risk to health, on risk management and risk communication. In summary, radon was confirmed as a human carcinogen. Indoor radon exposures resulting in individual risks exceeding 10 -3 per year are to be considered as severe and risk reduction programmes implemented. Guidance on risk management and communication is offered to national authorities. (author)

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)

Nationwide survey of radon levels in indoor workplaces in Mexico using Nuclear Track Methodology

International Nuclear Information System (INIS)

Espinosa, G.; Golzarri, J.I.; Angeles, A.; Griffith, R.V.

2009-01-01

This report presents the preliminary results of an indoor workplace radon survey conducted during 2006-2007. Monitoring was carried out in 24 of the 32 federal entities of Mexico, incorporating 26 cities and 288 locations. The area monitored was divided into 8 regions for the purposes of the study: Chihuahua (a state with uranium mines), North-Central, South-Central, Southeast, South, Northeast, Northwest, and West. These regions differ in terms of geographic and geological characteristics, climate, altitude, and building materials and architectonic styles. Nuclear Track Methodology (NTM) was employed for the survey, using a passive closed-end cup device with Poly Allyl Diglycol Carbonate (PADC), known by its trade name CR-39 (Lantrack), as detector material. Well-established protocols for making continuous indoor radon measurements were followed, including one-step chemical etching in a 6.25 M KOH solution at 60 ± 1 deg. C with an etching time of 18 h. The track densities were determined with an automatic digital system at the Instituto de Fisica de la Universidad Nacional Autonoma de Mexico (IFUNAM) (Physics Institute of the National Autonomous University of Mexico), and calibrated in facilities at the Oak Ridge National Laboratory (ORNL). The importance of this survey lies in the fact that it represents the first time a nationwide survey of radon levels in indoor workplaces has been carried out in Mexico. Mean indoor radon levels from continuous measurements taken during and after working hours ranged from 13 Bq m -3 (the lower limit of detection) to 196 Bq m -3 . Analogous official controls or regulations for radon levels in indoor workplaces do not exist in Mexico. The survey described here contributes to knowledge of the natural radiological environment in workplaces, and will aid the relevant authorities in establishing appropriate regulations. The survey was made possible by the efforts of both a private institutions and the Dosimeter Application Project

Study of indoor radon levels in some radioactive areas of Himachal Pradesh: an inter-comparison of active and passive techniques

International Nuclear Information System (INIS)

Bajwa, B.S.; Singh, S.; Sharma, N.; Virk, H.S.

2006-01-01

Full text of publication follows: Indoor radon levels measurements were carried using both the active and passive techniques in the dwellings of some villages, known to be located in the vicinity of uranium mineralized zones of Hamirpur district, Himachal Pradesh. Even in the passive technique using Solid State Nuclear Track Detectors (S.S.N.T.D.), both the bare-slide and twin chamber dosemeter cup modes were utilized. An attempt has also been made to assess the levels of the indoor radon in these dwellings and inhalation dose rates of the population living in these villages. The average value of radon concentration levels using the bare-slide mode varies from 109.0 to 741.5 Bq/m3 in these dwellings, where as the maximum radon level using the twin cup dosemeter technique was found to be 140.3 Bq/m3. As usual the radon concentrations were found to be varying with seasonal changes, building materials etc. The radon survey in the dwellings of these villages has also been carried out using the Alpha- Guard technique, which is based on the pulse ionization chamber. The indoor radon concentration levels measured using the active technique of Alpha Guard have been found to be quite different from those measured in these dwellings by the passive technique of S.S.N.T.D.; indicating the importance of the S.S.N.T.D. in the long-term integrated measurement of the indoor radon levels in the dwellings. (authors)

Hierarchical modeling of indoor radon concentration: how much do geology and building factors matter?

International Nuclear Information System (INIS)

Borgoni, Riccardo; De Francesco, Davide; De Bartolo, Daniela; Tzavidis, Nikos

2014-01-01

Radon is a natural gas known to be the main contributor to natural background radiation exposure and only second to smoking as major leading cause of lung cancer. The main concern is in indoor environments where the gas tends to accumulate and can reach high concentrations. The primary contributor of this gas into the building is from the soil although architectonic characteristics, such as building materials, can largely affect concentration values. Understanding the factors affecting the concentration in dwellings and workplaces is important both in prevention, when the construction of a new building is being planned, and in mitigation when the amount of Radon detected inside a building is too high. In this paper we investigate how several factors, such as geologic typologies of the soil and a range of building characteristics, impact on indoor concentration focusing, in particular, on how concentration changes as a function of the floor level. Adopting a mixed effects model to account for the hierarchical nature of the data, we also quantify the extent to which such measurable factors manage to explain the variability of indoor radon concentration. - Highlights: • It is assessed how the variability of indoor radon concentration depends on buildings and lithologies. • The lithological component has been found less relevant than the building one. • Radon-prone lithologies have been identified. • The effect of the floor where the room is located has been estimated. • Indoor radon concentration have been predicted for different dwelling typologies

Indoor radon concentration and its possible dependence on ventilation rate and flooring type

International Nuclear Information System (INIS)

Ashok, G. V.; Nagaiah, N.; Shiva Prasad, N. G.

2012-01-01

The results of radon concentration measurements carried out in dwellings with natural ventilation for 1 y in Bangalore are reported. Measurements, covering three sessions of the day (morning, afternoon, night) were performed two times in a month for 1 y at a fixed place of each dwelling at a height of 1 m above the ground surface in selected dwellings. The low-level radon detection system (LLRDS), an active method, was used for the estimation of radon concentration. The measurements were aimed to understand the diurnal variation and the effect of ventilation rate and flooring type on indoor radon concentration. The geometric mean (±geometric standard deviation) of indoor radon concentration from about 500 measurements carried out in 20 dwellings is found to be 25.4 ±1.54 Bq m -3 . The morning, afternoon and night averages were found to be 42.6 ±2.05, 15.3 ±2.18 and 28.5 ±2.2 Bq m -3 , respectively. The approximate natural ventilation rates of the dwellings were calculated using the PHPAIDA-the on-line natural ventilation, mixed mode and air infiltration rate calculation algorithm and their effects on indoor radon concentrations were studied. The inhalation dose and the lung cancer risk due to indoor radon exposure were found to be 0.66 mSv y -1 and 11.9 per 10 6 persons, respectively. The gamma exposure rate was also measured in all the dwellings and its correlation with the inhalation dose rate was studied. (authors)

Indoor air radon

International Nuclear Information System (INIS)

Cothern, C.R.

1990-01-01

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

Determination of indoor radon concentration levels and the associated annual effective dose rate in some Ghanaian dwellings

International Nuclear Information System (INIS)

Nsiah-Akoto, I.

2010-01-01

Radon and its decay products in indoor air are the main source of natural internal irradiation of man. In this present work, the indoor radon concentration, the annual exposure, the annual effective dose and the annual dose equivalent to the lung received by the population were estimated in the dwellings at Dome in the Ga-East District of the Greater Accra Region, Ghana using time-integrated passive radon detectors; LR-115 Type II solid state nuclear track detector (SSNTD) technique. The primary objective of this project was to assess the annual effective dose rate due to the indoor radon concentration levels and the associated level of risk. Measurements were carried out from December 2009 to March 2010. After the 3 months exposure, the detectors were subjected to chemical etching in a 2.5M analytical grade sodium hydroxide solution at (60 ±1) o C, for 90mins in a constant temperature water bath to enlarge the latent tracks produced by alpha particles from the decay of radon. The etched tracks were magnified using the microfiche reader and counted with a tally counter. The mean indoor radon concentration was found to be (466.9±1.2) Bqm -3 and the mean annual exposure was (2.03±0.08) WLM. Assuming an indoor occupancy factor of 0.4 and 0.4 for equilibrium factor for radon indoors, we found out that the mean Rn-222 effective dose rate and the annual equivalent dose rate to the lung in the present study dwellings was (14.13±0.22)mSvy -1 and (3.74 E-07 ±3.50 E-06)Svy -1 respectively. The mean values of radon concentrations at Dome, Kwabenya, Biakpa, and South-Eastern part of Ghana, Prestea and Kassena-Nakana District in the previous research ranged from (9.4±0.5) to (518.7±4.0) Bqm -3 . The mean annual exposure, annual effective dose rate and the annual equivalent for the previous work ranged from (0.04±0.03)WLM to (0.58±0.05)WLM, (0.28±0.08) to (15.54±0.69mSvy -1 ), (8.23E-12±4.33E-07) to (4.15E-07± 1.13E-04) respectively. Odds ratios (ORs) for lung

A study of diurnal variations of radon and thoron concentrations in different indoor environmental conditions

International Nuclear Information System (INIS)

Pant, Preeti; Prasad, Mukesh; Ramola, R.C.

2015-01-01

The measurements for diurnal variations in radon ( 222 Rn) and thoron ( 220 Rn) concentrations were performed in the different indoor conditions of Tehri Garhwal, Uttarakhand, India by using AlphaGUARD, Portable Radon Monitor and RAD7. While selecting the dwellings, the ventilation conditions, building materials, life style of the inhabitants and their exposure time indoors were also considered. The behavior of indoor radon and thoron concentrations was observed for different type of dwellings with different environmental conditions. The measurement techniques, results obtained and comparison of the results are discussed in details. (author)

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

Attempt to determine radon entry rate and air exchange rate variable in time from the time course of indoor radon concentration

Energy Technology Data Exchange (ETDEWEB)

Thomas, J [State Office for Nuclear Protection, Prague (Czech Republic)

1996-12-31

For radon diagnosis in houses the `ventilation experiment` was used as a standard method. After removal of indoor radon by draught the build-up of radon concentration a(t) [Bq/m{sup 3}] was measured continuously and from the time course the constant radon entry rate A [Bq/h] and the exchange rate k [h{sup -1}] was calculated by regression analysis using model relation a(t) A(1-e{sup -kt})/kV with V [m{sup 3}] for volume of the room. The conditions have to be stable for several hours so that the assumption of constant A and k was justified. During the day both quantities were independently (?) changing, therefore a method to determine variable entry rate A(t) and exchange rate k(t) is needed for a better understanding of the variability of the indoor radon concentration. Two approaches are given for the determination of variable in time radon entry rates and air exchange rates from continuously measured indoor radon concentration - numerical solution of the equivalent difference equations in deterministic or statistic form. The approaches are not always successful. Failures giving a right ration for the searched rates but not of the rates them self could not be explained.

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)

Investigation of the relationship between earthquakes and indoor radon concentrations at a building in Gyeongju, Korea

Directory of Open Access Journals (Sweden)

Jae Wook Kim

2018-04-01

Full Text Available This article measured and analyzed the indoor radon concentrations at one university building in Gyeongju, Republic of Korea, to investigate if there is any relationship between earthquakes and indoor radon concentration. Since 12 September 2016, when two 5.1 and 5.8 magnitude earthquakes occurred, hundreds of aftershocks affected Gyeongju until January 2017. The measurements were made at the ground floor of the Energy Engineering Hall of Dongguk University in Gyeongju over a period between February 2016 and January 2017. The measurements were made with an RAD7 detector on the basis of the US Environmental Protection Agency measurement protocol. Each measurement was continuously made every 30 minutes over the measurement period every month. Among earthquakes with 2.0 or greater magnitude, the earthquakes whose occurrence timings fell into the measurement periods were screened for further analysis. We observed similar spike-like patterns between the indoor radon concentration distributions and earthquakes: a sudden increase in the peak indoor radon concentration 1–4 days before an earthquake, gradual decrease before the earthquake, and sudden drop on the day of the earthquake if the interval between successive earthquakes was moderately longer, for example, 3 days in this article. Keywords: Earthquakes, Gyeongju, Indoor Radon Concentration, RAD7, Radon Anomaly

Prediction of indoor radon concentration based on residence location and construction

International Nuclear Information System (INIS)

Maekelaeinen, I.; Voutilainen, A.; Castren, O.

1992-01-01

We have constructed a model for assessing indoor radon concentrations in houses where measurements cannot be performed. It has been used in an epidemiological study and to determine the radon potential of new building sites. The model is based on data from about 10,000 buildings. Integrated radon measurements were made during the cold season in all the houses; their geographic coordinates were also known. The 2-mo measurement results were corrected to annual average concentrations. Construction data were collected from questionnaires completed by residents; geological data were determined from geological maps. Data were classified according to geographical, geological, and construction factors. In order to describe different radon production levels, the country was divided into four zones. We assumed that the factors were multiplicative, and a linear concentration-prediction model was used. The most significant factor in determining radon concentration was the geographical region, followed by soil type, year of construction, and type of foundation. The predicted indoor radon concentrations given by the model varied from 50 to 440 Bq m -3 . The lower figure represents a house with a basement, built in the 1950s on clay soil, in the region with the lowest radon concentration levels. The higher value represents a house with a concrete slab in contact with the ground, built in the 1980s, on gravel, in the region with the highest average radon concentration

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

Measurement and apportionment of radon source terms for modeling indoor environments

International Nuclear Information System (INIS)

Harley, N.H.

1990-01-01

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

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

International Nuclear Information System (INIS)

George, J.L.

1986-04-01

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

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

International Nuclear Information System (INIS)

Swedjemark, G.A.

1984-01-01

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

Long term indoor radon measurements in the pelletron laboratory at the UNAM physics institute

OpenAIRE

Espinosa, G.; Golzarri, J.I.; Lopez, K.; Rickards, J.

2011-01-01

The results of six months of continuous measurement of the indoor radon concentration levels in the building where the Instituto de Física 3 MV Pelletron particle accelerator is located are presented. This study has three major objectives: (a) to know the actual values of the levels of indoor radon in this installation, where personnel spend many hours and sometimes days; (b) assess the radiological risk from radon inhalation for personnel working permanently in the laboratory, as well as inc...

Design and evaluation of representative indoor radon surveys

International Nuclear Information System (INIS)

Csige, I.; Csegzi, S.

2004-01-01

We have developed a procedure to design and evaluate representative indoor radon surveys. The procedure is based on random sampling of a population of houses and careful statistical analysis of measured indoor radon concentrations. The method is designed to estimate the fraction of houses in which annual average 222 Rn activity concentration may exceed a certain reference level. Measurements of annual average indoor 222 Rn activity concentration were done in sleeping rooms at pillow level using etched track type radon detectors. We applied the above procedure in an old fashioned village and in a fast developing small city in Transylvania, Romania. In the village almost all houses were single floor wooden made houses without cellar built with traditional technology on a geologically uniform area. The distribution of indoor 222 Rn activity concentration in a sample of 115 houses can almost perfectly be fitted with log-normal probability density function. The correlation coefficient of linear fitting on linearized scales was k = -0.9980. The percentages of houses expected to have annual average 222 Rn activity concentration higher than 400 Bq m -3 is less than 1 %, and of those higher than 600 Bq m -3 can be estimated to be around 0.1 %. The small city, on the other hand lies on a geologically inhomogeneous area, and house construction technology has also changed dramatically in past decades. The resulting distribution of measured indoor 222 Rn activity concentration in a sample of 116 houses cannot be fitted with any simple probability density function. Therefore the prediction of the fraction of houses in which the annual average 222 Rn activity concentration may exceed a certain reference level could not be done adequately. With certain assumptions we estimated that the percentages of houses expected to have annual average 222 Rn activity concentration higher than 400 Bq m -3 is between 3 and 7 %, and of those higher than 600 Bq m -3 can be estimated to be between

Evaluation of annual effective dose from indoor radon concentration in Eastern Province, Dammam, Saudi Arabia

Science.gov (United States)

Abuelhia, E.

2017-11-01

The aim of this study is to determine the indoor radon concentration and to evaluate the annual effective dose received by the inhabitants in Dammam, Al-Khobar, and compare it with new premises built at university of dammam. The research has been carried out by using active detection method; Electronic Radon Detector (RAD-7) a solid state α-detector with its special accessories. The indoor radon concentration measured varies from 10.2 Bqm-3 to 25.8 Bqm-3 with an average value of 18.8 Bqm-3 and 19.7 Bqm-3 to 23.5 Bqm-3 with an average value of 21.7 Bqm-3, in Dammam and Al-khobar dwellings, respectively. In university of dammam the radon concentration varies from 7.4 Bqm-3 to 15.8 Bqm-3 with an average value of 9.02 Bqm-3. The values of annual effective doses were found to be 0.47mSv/y, 0.55mSv/y, and 0.23mSv/y, in Dammam, Al-khobar and university new premises, respectively. The average radon concentration in the old dwellings was two times compared to that in the new premises and it was 25.4 Bqm-3 lower than the world average value of 40 Bqm-3 reported by the UNSCEAR. The annual effective doses in the old dwellings was found to be (0.55mSv/y) two times the doses received at the new premises, and below the world wide average of 1.15mSv/y reported by ICRP (2010). The indoor radon concentration in the study region is safe as far as health hazard is concerned.

Assessment of indoor radon doses received by the students in the Azad Kashmir schools (Pakistan)

International Nuclear Information System (INIS)

Rafique, M.; Rahman, S. U.; Rahman, S.; Matiullah; Shahzad, M. I.; Ahmed, N.; Iqbal, J.; Ahmed, B.; Ahmed, T.; Akhtar, N.

2010-01-01

Several epidemiological studies conducted on thousands of underground miners suggest that long-term exposure to high radon concentration can increase the risk of lung cancer. Keeping in view the importance of the subject, numerous studies throughout the world have been carried out to measure indoor radon concentration and its resulting doses at occupational and non-occupational sites. The purpose of the current study was to measure indoor radon concentration and its resulting doses received by the students of Azad Kashmir government schools. For this purpose, CR-39 radon detectors were installed in 80 carefully selected schools. The detectors were placed at a height of 3-5 ft. (depending upon average height of students in particular class) from the ground. After exposure of 90 d detectors were etched for 9 h in 6 M NaOH at 70 deg. C and the observed track densities were related to radon concentrations. The measured indoor radon concentration ranged from 22 ± 9 to 228 ± 3 Bq m -3 with a mean value of 78 ± 5 Bq m -3 . Based on the measured indoor radon data, the annual effective doses were found to vary from 0.55 ± 0.04 to 0.71 ± 0.03 mSv y -1 . The overall mean effective dose for the studied area was found to be 0.63 ± 0.04 mSv y -1 . Reported values for radon concentrations and corresponding doses are lower than ICRP recommended limits for workplaces. (authors)

Indoor Radon Hazard: Impact Indices

International Nuclear Information System (INIS)

Alitto, G.; Nicoletti, G.

2006-01-01

How is possible to quantify, quickly, the effects of the Radon and the risk to it associated in relationship to the physical characteristics of the environments in which it is appraised? the concentration activity of Radon, valued in confined environments, it doesn't represent a meaningful and discriminating datum, or however exhaustive, for the respect of the negative effects from it induced. They exist, in fact, at the same concentration of the gas, different environmental configurations in which, risk related to exposure can also vary considerably. The estimation of the goodness of a indoor environment regarding ionizing radiations, excluding in this treatment those responsible of external exposure (gamma), it undoubtedly goes connected to a whole series of chemical-physical parameters proper of that environment. From this the demand has risen to create an impact index that kept track of all these aspects [it

Effectiveness of finish materials and room air-conditioner on the reduction of indoor radon concentration in Hong Kong

International Nuclear Information System (INIS)

Ma, A.K.; Man, C.K.; Ho, E.; Pang, S.W.

1995-01-01

Four different kinds of finish material were investigated: wallpaper, paint, plaster and tile. When applied to the bare concrete walls of uninhabited rooms in flats of a building under construction, all of them were found to reduce indoor radon concentration. The magnitude of reduction by these finish materials ranged from 20% to 80%. Wallpaper was found to provide the best protection against radon emission from bare concrete walls in a bedroom with a size of 19.3 m 3 . Wallpaper can reduce the indoor radon concentration about twice as much as paint (water-based) or plaster in this investigation. Tile was also found to be a good material against radon emission from concrete walls in a bathroom with a size of 6.3 m 3 . Indoor radon concentration was found to decrease with elevation from the ground level, and was affected strongly by mechanical ventilation. Another 30% to 50% reduction in indoor radon concentration in addition to finish material can be achieved by a room air-conditioner. It was also found that indoor radon concentrations were not affected by turning the fresh air shutter to the 'on' or 'off' position in the room air-conditioner. (author)

Measurements of Indoor Radon Concentrations in Chaiya and Tha Chana Districts, Surat Thani Province, Thailand

International Nuclear Information System (INIS)

Titipornpun, K.; Titipornpun, A.; Sola, P.; Bhongsuwan, T.

2014-01-01

Chaiya and Tha Chana districts of Surat Thani province are located in the areas with high equivalent uranium at ground surface, which have been identified as sources of radon. A survey measurement of indoor radon concentrations was carried out in 248 houses, using CR-39 detectors in closed cups. All of the detectors were exposed to radon for forty days. After the exposure, the alpha tracks were made visible by chemical etching and counted manually under an optical microscope. The indoor concentrations in Chaiya district were found to vary from the minimum to the maximum of 4 Bq.m -3 to 88 Bq.m -3 , respectively. In Tha Chana district, the concentrations of indoor radon were varied from the minimum of 4 Bq.m -3 to the maximum of 159 Bq.m -3 . The geometric mean of indoor radon concentrations in Chaya and Tha Chana districts were found to be 26±2 Bq.m -3 and 30±2 Bq.m -3 , respectively. The overall geometric mean in the surveyed areas was 28±2 Bq.m -3 . Only in two houses (1%), the concentrations (151 and 159 Bq.m -3 ) were found to be higher than the action level recommended by the US EPA (148 Bq.m -3 ). Most houses (94%) have natural ventilation by keeping doors and windows opened during the daytime. This ventilation likely causes the low level of indoor radon concentrations.

Measurement of indoor radon Concentrations in Osaka, Nara, Wakayama and Hyogo with passive dosemeters

International Nuclear Information System (INIS)

Mori, Toshiaki; Hori, Yasuharu; Takeda, Atsuhiko; Iwasaki, Tamiko; Uchiyama, Masahumi; Fujimoto, Kenzo; Kankura, Takako; Kobayashi, Sadayosi.

1989-01-01

Indoor radon concentrations of 792 houses in Osaka, Nara, Wakayama and Hyogo were measured by the passive dosemeter which was developed in Karlsruhe Nuclear Research Center in West Germany. Each house was measured at two places for successive two periods of six months to obtain annual average exposure due to radon daughters. The arithmetic mean concentration of all houses was 45.2 Bq/m 3 with a standard deviation of 27.2; the geometric mean, 40.7 Bq/m 3 and the median, 39 Bq/m 3 . The distribution of the radon levels was approximately log-normal with 80% of houses having radon concentrations less than 60 Bq/m 3 . The seasonal variation of the mean radon concentration was evident between the former period including winter value of 45 Bq/m 3 and the latter including summer value of 32 Bq/m 3 . The indoor radon concentrations of wooden houses were found to have the widest distribution with the highest value of 371 Bq/m 3 . The highest value obtained in the ferro-concrete house was 118 Bq/m 3 . Twelve houses having indoor radon concentrations higher than 120 Bq/m 3 were all Japanese traditional wooden houses with walls made of soil. (author)

Evaluation of indoor radon equilibrium factor using CFD modeling and resulting annual effective dose

Science.gov (United States)

Rabi, R.; Oufni, L.

2018-04-01

The equilibrium factor is an important parameter for reasonably estimating the population dose from radon. However, the equilibrium factor value depended mainly on the ventilation rate and the meteorological factors. Therefore, this study focuses on investigating numerically the influence of the ventilation rate, temperature and humidity on equilibrium factor between radon and its progeny. The numerical results showed that ventilation rate, temperature and humidity have significant impacts on indoor equilibrium factor. The variations of equilibrium factor with the ventilation, temperature and relative humidity are discussed. Moreover, the committed equivalent doses due to 218Po and 214Po radon short-lived progeny were evaluated in different tissues of the respiratory tract of the members of the public from the inhalation of indoor air. The annual effective dose due to radon short lived progeny from the inhalation of indoor air by the members of the public was investigated.

Concentration levels of radon in air, indoors and outdoors in houses of Mexico City

International Nuclear Information System (INIS)

Pena Garcia, P.

1992-01-01

Concentration levels of radon in air, indoors and outdoors have been obtained in houses from Mexico City, with the purpose of relating them with the local environment. Measurements were performed both outdoors and indoors in 60 unifamiliar houses. Track detectors, LR-115, Type II, were used in several detection arrangements during four recording periods with times of exposure of three months each, with the purpose of analyzing the fluctuations due to seasonal changes. Data were obtained about the construction materials were the detection systems were located in order to establish a correlation of radon levels with the climatic parameters and the construction materials. The results of radon concentrations both indoors or outdoors were lower than the international recommendations (148 Bq/m 3 ) (Author)

Environmental radon studies using solid state nuclear track detectors

International Nuclear Information System (INIS)

Singh, Surinder; Sharma, Dinesh Kumar; Kumar, Ajay

2004-01-01

The results of radon activity recorded in 70 dwellings of Nurpur area, Kangra district, Himachal Pradesh, India are reported. LR-115 Type 2 films in the bare mode were exposed for four seasons of three months each covering a period of one year for the measurement of indoor radon levels. The calibration constant of 0.020 tracks cm -2 d -1 per Bq m -3 has been used to express radon activity in Bq m -3 . The annual average indoor radon concentrations in 17 different villages of the area are found to vary from 168±46 to 429±71 Bq m -3 . Most of the indoor radon values lie in the range of action levels (200-600 Bq m -3 ) recommended by International Commission on Radiological Protection

Lung cancer mortality and indoor radon concentrations in 18 Canadian cities

International Nuclear Information System (INIS)

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

1983-01-01

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

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)

Systematic indoor radon and gamma-ray measurements in Slovenian schools

International Nuclear Information System (INIS)

Vaupotic, J.; Sikovec, M.; Kobal, I.

2000-01-01

During the winter months of 1992/93 and 1993/94, instantaneous indoor radon concentrations and gamma dose rates were measured in 890 schools in Slovenia attended in total by about 280,000 pupils. Under closed conditions, the room to be surveyed was closed for more than 12 h prior to sampling, the air was sampled into alpha scintillation cells with a volume of 700 cm 3 , and alpha activity was measured. An arithmetic mean of 168 Bq m -3 and a geometric mean of 82 Bq m -3 were obtained. In 67% of schools, indoor radon concentrations were below 100 Bq m -3 , and in 8.7% (77 schools with about 16,000 pupils) they exceeded 400 Bq m -3 , which is the proposed Slovene action level. In the majority of cases, radon concentrations were high due to the geological characteristics of the ground. Approximately 70% of schools with high radon levels were found in the Karst region. Gamma dose rates were measured using a portable scintillation counter. An arithmetic mean of 102 nGy h -1 and a geometric mean of 95 nGy h -1 were obtained. No extraordinarily high values were recorded

Influence of environmental factors on indoor radon concentration levels in the basement and ground floor of a building – A case study

International Nuclear Information System (INIS)

Xie, Dong; Liao, Maili; Kearfott, Kimberlee J.

2015-01-01

A series of experiments was conducted to measure indoor radon concentrations variations and observe any correlations with indoor and outdoor atmospheric parameters for over a period of one year. Indoor environmental parameters and radon concentrations were measured on an hourly basis in a two-story building both in a laboratory on the well-ventilated ground floor and in the basement below it which had negligible ventilation. The monthly average indoor radon concentration value of 29 ± 21 Bq m"−"3 in the laboratory was below the ICRP recommended limit of 200–300 Bq m"−"3. The monthly normalization factor for that location ranged from 0.5 to 2.0, while the seasonal normalization factor ranged from 0.78 to 2.0. In the unventilated basement, however, the average monthly indoor radon concentration was 1083 ± 6 Bq m"−"3 with little seasonal variation. The basement is only used for storage and thus the elevated radon concentration does not pose a serious health risk. The results indicated that indoor radon levels are higher in the autumn–winter season than in the spring–summer season. Analysis further showed that indoor radon concentrations negatively correlated with indoor humidity (correlation coefficient R = −0.14, p < 0.01), outdoor temperature (correlation coefficient R = −0.3, p < 0.01), outdoor dew point temperature (correlation coefficient R = −0.17, p < 0.01) and outdoor wind speeds (correlation coefficient R = −0.25, p < 0.05). Radon concentrations correlated positively with outdoor barometric pressure (correlation coefficient R = 0.35, p < 0.01), indoor–outdoor temperature difference (correlation coefficient R = 0.32, p < 0.05) and indoor–outdoor barometric pressure difference (correlation coefficient R = 0.67, p < 0.01). Indoor temperature, indoor barometric pressure and outdoor wind direction showed no clear correlations with indoor radon concentration. - Highlights: • Environmental variables and

Indoor radon concentration measurements in Tarqumia Girl Schools at Western Hebron Region, Palestine

International Nuclear Information System (INIS)

Dabyneh, K.M.

2006-01-01

In this study, radon-222 in indoor air was surveyed in 62 rooms located in four governmental schools, for girls, in Tarqumia town that lies in the north western part of Hebron city in Palestine. The annual effective dose equivalents resulting from the inhalation of radon and its daughters by 2318 pupils and 102 staff members occupying the surveyed rooms were also measured. TASTRAK, a solid state nuclear track detector, has been used to measure the indoor radon concentrations at those schools thus, 124 radon detectors were distributed in the four school buildings. The radon detectors stayed for 70 days between February 2006 and April 2006. The results showed that the radon concentration and the annual effective dose equivalent in these schools were varied from 12 to 232.5 Bq/m 3 with an average of 34.1 Bq/m 3 and 0.62 to 12.0 mSv/y with an average of 1.76 mSv/y, respectively. The mean values of radon concentrations in Tarqumia secondary girls school, Al-aqsa elementary girls school, Umsalama elementary girls school and Tarqumia elementary girls school were 35.8, 26.7, 25.9 and 47.8 Bq/m 3 , respectively, and the mean values of the annual effective dose equivalent for the above mentioned were 1.85, 1.38, 1.34 and 2.47 mSv/y, respectively. It has been found from these results that, most of the values were of nominal state values (that is less than the allowed global values) and in few places, the concentration was higher than the allowed global values, therefore, the annual effective dose higher than annual global level values (1.3 mSv/y) was resulted. Poor ventilation and old buildings were, most mobility, the main cause of these high radon concentrations. Improving ventilation of these places will increase air exchange rates with the out side, thereby resulting in reduced concentration. In general, the results showed that protection against radiological hazards would not be necessary for pupils and staff members occupying the rooms of the investigated schools

Indoor radon levels in schools of South-East Italy

International Nuclear Information System (INIS)

Trevisi, Rosabianca; Leonardi, Federica; Simeoni, Carla; Tonnarini, Sabrina; Veschetti, Miriam

2012-01-01

A survey was conducted to evaluate average levels of indoor radon and gamma doses in all educational buildings (506 schools) located in South-East Italy (the Salento peninsula, province of Lecce). In this paper the final findings relating to measurements performed with SSNTD dosemeters in 438 schools (86% of the sample) are reported. The average annual activity concentration of radon in schools located in the province of Lecce is 209 ± 9 Bq/m 3 . Radon values actually ranged from 21 Bq/m 3 to 1608 Bq/m 3 . About 7% of schools showed radon concentration values above 500 Bq/m 3 , the Italian action level for workplaces. - Highlights: ► The annual radon concentration in schools of the province of Lecce is 209 ± 9 Bq/m 3 . ► Schools radon values (209 ± 9 Bq/m 3 ) are higher than the regional average (52 ± 2 Bq/m 3 ). ► Nursery schools showed higher radon values. ► Nursery schools had the highest percentage of schools (12%) over 500 Bq/m 3 .

Measurement and apportionment of radon source terms for modeling indoor environments

International Nuclear Information System (INIS)

Harley, N.H.

1992-01-01

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

Concentrations of indoor radon and thoron in cave-dwellings with discussions on risk estimation of lung cancer

International Nuclear Information System (INIS)

Sun Quanfu; Hou Changsong; Zhang Shouzhi; Nie Xiaoqian; Shang Bing

2005-01-01

Objective: To explore a residential area with elevated indoor radon exposure for conducting epidemiological studies on indoor radon and lung cancer. Methods: Two hundred and two cave-dwellings (CD) including loess CD, brick CD, stone CD, and ordinary house in twenty villages were selected from Yan'an and Lvliang in the Chinese loess plateau. Indoor levels of thoron and its progeny as well as radon were measured with passive radon-thoron discriminative detectors and thoron progeny deposition rate devices. The exposure period covered from August 2001 through August 2002. Results: Loess CD was one of the most common type of dwelling caves in both areas. The indoor radon concentrations in loess CD ranged from 17 to 179 Bq/m 3 ; thoron varied sub-stantially depending upon the distance from the device to the wall, ranged from 10 to 760 Bq/m 3 . Geometric means of indoor radon, thoron and thoron's progeny (EEC Tn ) of loess caves in Yan'an area were estimated to be 71, 185 and 2.2 Bq/m 3 , respectively, and the corresponding figures were 73, 145 and 116 Bq/m 3 in Lvliang area. Possible contamination of thoron on radon measurement in a previous case-control study on lung caner was discussed. The study revealed that the indoor air pollution in Yan'an area was slight compared with that in Lvliang area. Migration was very low. Eighty-six percent of the investigated persons have had no migration in Yan'an area, and 90 percent of the cave-dwellings where the subjects once resided were available to our measurements. Two million people have been living in cave-dwellings over several generations. Conclusion: The investigated cave-dwelling area in Yan'an is suitable for conducting epidemiological study on residential thoron and radon exposure and lung cancer.(authors)

An assessment of ecological and case-control methods for estimating lung cancer risk due to indoor radon

International Nuclear Information System (INIS)

Stidley, C.A.; Samet, J.M.

1992-01-01

Studies of underground miners indicate that indoor radon is an important cause of lung cancer. This finding has raised concern that exposure to radon also causes lung cancer in the general population. Epidemiological studies, including both case-control and ecological approaches, have directly addressed the risks of indoor residential radon; many more case-control studies are in progress. Ecological studies that associate lung-cancer rates with typical indoor radon levels in various geographic areas have not consistently shown positive associations. The results of purportedly negative ecological studies have been used as a basis for questioning the hazards of indoor radon exposure. Because of potentially serious methodologic flaws for testing hypotheses, we examined the ecological method as a tool for assessing lung-cancer risk from indoor radon exposure. We developed a simulation approach that utilizes the Environmental Protection Agency (EPA) radon survey data to assign exposures to individuals within counties. Using the computer-generated data, we compared risk estimates obtained by ecological regression methods with those obtained from other regression methods and with the open-quotes trueclose quotes risks used to generate the data. For many of these simulations, the ecological models, while fitting the summary data well, gave risk estimates that differed considerably from the true risks. For some models, the risk estimates were negatively correlated with exposure, although the assumed relationship was positive. Attempts to improve the ecological models by adding smoking variables, including interaction terms, did not always improve the estimates of risk, which are easily affected by model misspecification. Because exposure situations used in the simulations are realistic, our results show that ecological methods may not accurately estimate the lung-cancer risk associated with indoor radon exposure

The ORNL Indoor Air Quality Study: Re-cap, Context, and Assessment on Radon

Energy Technology Data Exchange (ETDEWEB)

Tonn, Bruce Edward [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Rose, Erin M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ternes, Mark P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2015-10-01

As part of the retrospective evaluation of the U.S. Department of Energy s low-income Weatherization Assistance Program that was led by Oak Ridge National Laboratory (ORNL), an assessment of the impacts of weatherization on indoor air quality (IAQ) was conducted. This assessment included nearly 500 treatment and control homes across the country. Homes were monitored for carbon monoxide, radon, formaldehyde, temperature and humidity pre- and post-weatherization. This report focuses on the topic of radon and addresses issues not thoroughly discussed in the original IAQ report. The size, scope and rigor of the radon component of the IAQ study are compared to previous studies that assessed the impacts of weatherization on indoor radon levels. It is found that the ORNL study is by far the most extensive study conducted to date, though the ORNL results are consistent with the findings of the other studies. However, the study does have limitations related to its reliance on short-term measurements of radon and inability to attribute changes in radon levels in homes post-weatherization to specific weatherization measures individually or in combination.

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

Energy Technology Data Exchange (ETDEWEB)

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

1984-04-01

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

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

International Nuclear Information System (INIS)

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

1984-04-01

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

Indoor radon related to uranium in granitoids of the Central Bohemian plutonic complex

International Nuclear Information System (INIS)

Barnet, I.; Fojtikova, I.

2004-01-01

The study is based on the indoor radon data (one year measurements, Kodak LR 115 track etch detectors), vectorized geological maps 1:50000, vectorized coordinates of dwellings and uranium data for granitoid types of the Central Bohemian Plutonic Complex (CBPC). Using ArcGis 8.2 programme, the position of 16145 dwellings was linked to a geological database covering the CBPC (approx. 3200 km 2 ), and the type of underlying rock type was specified for each house. The resulting databases enabled us to calculate the mean EEC indoor Rn data for particular granitoid types and to study the relationship between the indoor Rn and the U concentrations. The petrogenetically variable CBPC was emplaced during Variscan orogenesis (330-350 Ma) and is among the most radioactive rock types within the Bohemian Massif. A long-term process of CBPC genesis resulted in more than 20 granitoid types, differing by their petrogenetic characteristics as well as mineralogical and chemical composition, including uranium concentration. The relation between the mean indoor radon values and uranium concentrations in particular rock types was examined. A positive regression between indoor Rn and uranium as the source of Rn soil gas clearly demonstrates how regional geology influences the indoor radon activity concentration in dwellings. The highest indoor Rn concentrations were observed in the Sedlcany granodiorite and Certovo bremeno syenite, where also the highest gamma dose rates (150-210 nGy.h -1 ) within all granitoid types in the Czech Republic were observed. The two rock types differ from other granitoids by a relatively high zircon concentration, which is the main source of U and subsequently of soil gas Rn being released from the bedrock. The lower indoor Rn values of Certovo bremeno syenite which do not correspond with the high U concentrations can be explained by a relatively low permeability of its clayey weathering crust. This feature was also observed for soil gas radon concentration

Effects of bedrock type on the indoor radon concentrations at the office buildings in Gyeongju, Korea

Directory of Open Access Journals (Sweden)

Park Hee Chan

2011-01-01

Full Text Available This study measured the indoor radon concentrations at 23 administrative office buildings in Gyeongju, Korea, which consists of 23 administrative districts. Using the Korean geological information system, the type of bedrock under the administrative office buildings was identified and classified in 3 major types: granite, sedimentary rock, and sedimentary rock-based fault. The changes in the indoor concentrations at the 23 administrative office buildings were analyzed according to the type of bedrock. As a result, the radon concentration in the areas with the granite bedrock was generally higher than that in the region of two other types of bedrock. In addition, the radon concentration was evaluated according to surface area and construction timing of the building. The indoor radon concentration generally increased with decreasing surface area of the building, particularly in granite distributed areas. For a building aged more than 15 years, the radon concentration in the building in the granite area was much higher. For the building aged 1 or 2 years, the radon concentration was high regardless of the type of the bedrock due to radon emanation from the building material, such as concrete.

Radon-222 Study in Ceramics and Indoor Air

International Nuclear Information System (INIS)

Moussa, N.L.A.A.

2011-01-01

A total 50 samples of 13 different ceramic tiles companies collected from the Egyptian market for the measurements of radon exhalation rate. Three homes include twenty rooms were selected. The period of the survey was in range 2-3 months for homes for each season while it was about 15 days for ceramic tiles. The radon exhalation rate of ceramic tiles (clay and glaze) and indoor radon activity concentration were measured by alpha tracks technique. The average radon exhalation rate in three homes was observed to be in the range 2.2-5.2 mBq.m -2 .h -1 . The average of Ra-226 activity for all ceramic tiles either the floor or wall tile is in the range 16-64 Bq.kg -1 . The porosity of ceramic tiles is found in the range 0.19-0.29. The effective dose in all rooms is found in the range 0.9- 1.3 mSv.y -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)

Distribution of indoor radon concentrations and elements of a strategy for control

International Nuclear Information System (INIS)

Nero, A.V. Jr.

1986-05-01

Indoor radon concentrations vary widely in the US housing stock, with normal concentrations estimated to cause a significant risk of lung cancer by comparison with environmental exposures normally considered, and high concentrations causing risks that exceed even those from cigarette smoking. The probability distribution, i.e., the number of houses at various concentrations, can be estimated from an analysis of the US indoor radon data accumulated to date. Such an analysis suggests that in about a million houses, occupants are receiving exposures greater than those experienced by uranium miners. The form of the frequency distribution, including not only the average concentration, but also the number of houses with high levels, has substantial influence on strategies for control of indoor radon. Such strategies require three major elements: formulation of control objectives in terms of guidelines for remedial action and for new houses; selection of means for identifying homes with high concentrations; and a framework for deciding what types of control measures are appropriate to particular circumstances and how rapidly they should be employed

Tempts to determine radon entry rate and air exchange rate variable in time from the time course of indoor radon concentration

International Nuclear Information System (INIS)

Thomas, J.

1996-01-01

For the study and explanation of the diurnal variability of the indoor radon concentration a(t) [Bq/m 3 ], which is proportional to the ratio of the radon entry rate A [Bq/h] and the air exchange rate k [1/h], it would be of advantage to know separately the diurnal variability of both determining quantities A(t) and k(t). To measure directly and continuously the radon entry rate A(t) is possible only in special studies (mostly in experimental rooms) and also continuous measuring of the air exchange rate k(t) is possible also only in special studies for a short time. But continuously measuring radon meters are now common, do not trouble people in normal living regime during day and night. The goal of this endeavour would be the evaluation of the time courses of both determining quantities from the time courses of the indoor radon concentration directly without additional experimental work and so a better utilisation of such measurements. (author)

Log-normality of indoor radon data in the Walloon region of Belgium

International Nuclear Information System (INIS)

Cinelli, Giorgia; Tondeur, François

2015-01-01

The deviations of the distribution of Belgian indoor radon data from the log-normal trend are examined. Simulated data are generated to provide a theoretical frame for understanding these deviations. It is shown that the 3-component structure of indoor radon (radon from subsoil, outdoor air and building materials) generates deviations in the low- and high-concentration tails, but this low-C trend can be almost completely compensated by the effect of measurement uncertainties and by possible small errors in background subtraction. The predicted low-C and high-C deviations are well observed in the Belgian data, when considering the global distribution of all data. The agreement with the log-normal model is improved when considering data organised in homogeneous geological groups. As the deviation from log-normality is often due to the low-C tail for which there is no interest, it is proposed to use the log-normal fit limited to the high-C half of the distribution. With this prescription, the vast majority of the geological groups of data are compatible with the log-normal model, the remaining deviations being mostly due to a few outliers, and rarely to a “fat tail”. With very few exceptions, the log-normal modelling of the high-concentration part of indoor radon data is expected to give reasonable results, provided that the data are organised in homogeneous geological groups. - Highlights: • Deviations of the distribution of Belgian indoor Rn data from the log-normal trend. • 3-component structure of indoor Rn: subsoil, outdoor air and building materials. • Simulated data generated to provide a theoretical frame for understanding deviations. • Data organised in homogeneous geological groups; better agreement with the log-normal

Radon measurements in air in waterworks and indoor swimming pools - a primary mapping project

International Nuclear Information System (INIS)

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

2004-01-01

In 2001 the Swedish Work Environment Authority asked five regional offices around the country; Falun, Malmoe, Vaexjoe, Umeaa and Oerebro, to measure radon in air in workplaces where water was likely to enhance radon levels indoors. Track etch detectors were used and placed in workplaces according to the SSI measurement protocol for determining the annual average radon concentration in homes. Rooms that are frequently used by employees were measured. The detectors were exposed between 1 to 3 months. 225 detectors were used in the project and analysed at the same laboratory. The results showed that the radon concentration in waterworks often is high. Measurements were made in 60 waterworks. Levels exceeding 1000 Bq/m 3 were found in 49 of them and levels exceeding 4000 Bq/m 3 were found in 21 waterworks. The variation between waterworks may be a result of the radon concentration in the raw water, the amount of radon gas escaping to the air when water is treated, the air exchange rate in the building and where the detectors were deployed. Measurements were made in 28 indoor swimming baths. The maximum level was 290 Bq/m 3 , but most concentrations were between 30 to 70 Bq/m 3 . The conclusion is that high radon levels do not seem to be a problem in indoor swimming baths. Maybe this is due to good ventilation or the fact that water often has been treated for radon before it is used in swimming pools. The results from measurement in food industries such as breweries showed no extreme radon levels except for a fish farm where levels over 1000 Bq/m 3 were measured in the farming room and 790 Bq/m 3 in the office. The radon concentrations in laundries were relatively low, between 30 and 170 Bq/m 3

Comparison of two methods for investigating indoor radon daughters

International Nuclear Information System (INIS)

Vanmarcke, H.; Raes, F.

1988-01-01

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

Indoor radon in rural dwellings of the South-Pannonian region

International Nuclear Information System (INIS)

Forkapic, S.; Bikit, I.; Slivka, J.; Conkic, L.; Veskovic, M.; Todorovic, N.; Varga, E.; Mrdda, D.; Hulber, E.

2007-01-01

The results of indoor radon survey in the South-Pannonian Province Vojvodina (Serbia and Montenegro) are presented. The sampling strategy was oriented towards suburban and urban regions in the Province. For the dwellings typical for such regions the geometric mean annual radon activity concentration of 76.1 Bq m -3 is measured (1000 measurements). This result leads to the annual dose estimate of 4.3 mSv y -1 , which is above the recommended action limit of ICRP. For urban dwellings in Novi Sad (the Province capital), the annual mean value of 54 Bq m -3 (220 measurements) is obtained. By comparison of these two results it is concluded that radon surveys based on measurements in urban environment may seriously underestimate the radon-related health risk. The elevated radon levels could not be explained by elevated uranium levels of surface soil. (authors)

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)

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.

[sup 210] Po as a long-term integrating radon indicator in the indoor environment

Energy Technology Data Exchange (ETDEWEB)

1992-01-01

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

[sup 210] Po as a long-term integrating radon indicator in the indoor environment

Energy Technology Data Exchange (ETDEWEB)

1992-01-01

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

Indoor radon distribution in metropolitan region of Belo Horizonte, Brazil

International Nuclear Information System (INIS)

Santos, Talita O.; Oliveira, Arno H. de

2009-01-01

Human beings are exposed to ionizing radiation from many natural sources. Radon and its progeny have been recognized as the most important contributors to the natural radioactivity dose, accounting for about half of all human exposure to ionizing radiation. Radon ( 222 Rn) is a α-radioactive noble gas derived from the natural series of uranium (2 38 U), which occurs in a wide concentration range in all geological materials, especially, in rocks, soils and waters. By diffusion and convection, radon migrates from the rocks and soils to atmosphere and through fissures, pipes and holes it may enter the dwellings and other buildings. Another important radon source in dwellings is its emanation from the construction material. The radon progeny concentration in dwellings has been receiving considerable global attention due to its potential effect in causing lung cancer if it deposited in upper respiratory tract when inhaled. This paper presents radon concentration distribution in dwellings in Metropolitan Region of Belo Horizonte - RMBH. The effective dose estimate is also presented for the RMBH inhabitants. The geological settings of the area are Archean rocks of Granitic Gnaissic Complex and of metasediments sequences of the great Precambrian unit of the Iron Quadrangle of Minas Gerais, Brazil. Radon concentration measurements were carried out with continuous detector AlphaGUARD PQ200PRO (Genitron), in passive mode and with passive detectors E-PERM R Eletret Ion Chamber-EIC. The radon progeny concentration was carried out with a solid state alpha spectroscope, the DOSEman PRO (Sarad). It was found an indoor radon concentration varying in a large range from 18.5 to 2671.4 Bq/m -3 , with an average value of 148.0 Bqm -3 and geometric mean equal to 128.2 Bqm -3 . The variable results are due mainly to region geological factors and building material composition of dwellings. The equilibrium factor between radon and its progeny were determined in dwellings, as 0.3 in

Uranium in soil and gamma dose rate as proxies for the indoor radon risk: situation in Belgium

International Nuclear Information System (INIS)

Tondeur, F.; Cinelli, G.; Dehandschutter, B.

2017-01-01

Radon risk maps are usually based either on indoor radon data, or on measurements of soil gas radon and soil permeability. If these data are not available or not sufficient, it was suggested that other data could be used as an approximate substitute (a proxy) to the missing information, like the concentration of 238 U or 226 Ra in soils or the terrestrial gamma dose rate (TGDR). We examine here the correlation between airborne measurements of soil U and indoor radon, and between airborne U and TGDR, and their link with affected/unaffected areas. No clear correlation is found between airborne U and affected areas, as strongly affected areas are not characterised by a higher U level. Only the moderately affected area of Condroz can be connected to a higher U level, related to a few U anomalies. TGDR shows a rather good correlation with airborne U, but its relation with radon risk is less clear. Soil uranium and TGDR may help to screen out areas with very low U and very low TGDR, which have a low indoor radon risk, but they cannot be considered as good proxies for predicting radon-affected areas in Belgium. (authors)

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

International Nuclear Information System (INIS)

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

1988-05-01

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

Indoor air radon dose assessment for elementary, middle and high schools at Ulju county in Korea

International Nuclear Information System (INIS)

Lee, Choong Wie; Kim, Hee Reyoung

2016-01-01

Ulsan is the largest industrial city and possesses the largest area among 7 metropolitan cities in Korea. Ulju county is one of the administrative districts of Ulsan, and covers over 70 % of Ulsan and is surrounded by mountain to the east and sea to the west, which has urban and rural area. Thus, there are many geological and industrial condition in its environment. Ministry of Environment (ME) of Korea is carrying out radon survey every 2 years, but this survey focuses on radon radioactivity of the houses and radon survey for schools isn't detailed. At schools, people with various age work and are educated for a specific time, therefore, it is needed to analyze the radon radioactivity concentration of indoor air to estimate the effect by the radon exposure. Indoor air radon radioactivity concentration and dose of 57 schools including elementary, middle and high schools in Ulju county were analyzed by using alpha track. It was understood that average radon concentrations of schools in Ulju county were being maintained below recommendation level although survey results of some schools showed 295 Bq/m 3 higher than regulation of Ministry of Environment for radon concentration, 148 Bq/m 3 . Indoor annual effective dose of 0.157 mSv by radon was found to be less than 7 % of the natural radiation exposure of 2.4 mSv when ICRP dose coefficient for adult male was applied. It was thought that further radon effect analysis for various ages including children was needed for more accurate dose assessment

Indoor air radon dose assessment for elementary, middle and high schools at Ulju county in Korea

Energy Technology Data Exchange (ETDEWEB)

Lee, Choong Wie; Kim, Hee Reyoung [KAERI, Daejeon (Korea, Republic of)

2016-05-15

Ulsan is the largest industrial city and possesses the largest area among 7 metropolitan cities in Korea. Ulju county is one of the administrative districts of Ulsan, and covers over 70 % of Ulsan and is surrounded by mountain to the east and sea to the west, which has urban and rural area. Thus, there are many geological and industrial condition in its environment. Ministry of Environment (ME) of Korea is carrying out radon survey every 2 years, but this survey focuses on radon radioactivity of the houses and radon survey for schools isn't detailed. At schools, people with various age work and are educated for a specific time, therefore, it is needed to analyze the radon radioactivity concentration of indoor air to estimate the effect by the radon exposure. Indoor air radon radioactivity concentration and dose of 57 schools including elementary, middle and high schools in Ulju county were analyzed by using alpha track. It was understood that average radon concentrations of schools in Ulju county were being maintained below recommendation level although survey results of some schools showed 295 Bq/m{sup 3} higher than regulation of Ministry of Environment for radon concentration, 148 Bq/m{sup 3}. Indoor annual effective dose of 0.157 mSv by radon was found to be less than 7 % of the natural radiation exposure of 2.4 mSv when ICRP dose coefficient for adult male was applied. It was thought that further radon effect analysis for various ages including children was needed for more accurate dose assessment.

Indoor radon seasonal variability at different floors of buildings

International Nuclear Information System (INIS)

De Francesco, S.; Tommasone, F. Pascale; Cuoco, E.; Tedesco, D.

2010-01-01

Indoor radon concentrations have been measured with the α track etch integrated method in public buildings in the town of Pietramelara, north-western Campania, Southern Italy. In particular, our measurements were part of an environmental monitoring program originally aimed at assessing the range of seasonal fluctuations in indoor radon concentrations, at various floors of the studied buildings. However, subsequent analysis of the data and its comparison with the meteorological data recorded in the same period has shown an unexpected pattern at the different floors. In this report we present data suggesting that, besides the well-known medium and longterm periodicity, there could also be a differentiation in major meteorological controlling factors at the different floors of the buildings, a fact that does not appear to have been reported previously. While the lower floors proved to be markedly affected by rainfall, for the upper floors, instead, a different behaviour has been detected, which could possibly be related to global solar radiation.

The perceived health risks of indoor radon gas and overhead powerlines: a comparative multilevel approach.

Science.gov (United States)

Poortinga, Wouter; Cox, Patrick; Pidgeon, Nick F

2008-02-01

Radon and overhead powerlines are two radiation risk cases that have raised varying levels of concern among the general public and experts. Despite both involving radiation-a typically feared and unseen health hazard-individuals' perceptions of the two risk cases may invoke rather different factors. We examined individual and geographic-contextual factors influencing public perceptions of the health risks of indoor radon gas and overhead powerlines in a comparative research design, utilizing a postal questionnaire with 1,528 members of the general public (response rate 28%) and multilevel modeling techniques. This study found that beliefs about the two risk cases mainly differed according to the level of "exposure"-defined here in terms of spatial proximity. We argue that there are two alternative explanations for this pattern of findings: that risk perception itself varies directly with proximity, or that risk is more salient to concerned people in the exposed areas. We also found that while people living in high radon areas are more concerned about the risks of indoor radon gas, they find these risks more acceptable and have more trust in authorities. These results might reflect the positive effects of successive radon campaigns in high radon areas, which may have raised awareness and concern, and at the same time may have helped to increase trust by showing that the government takes the health risks of indoor radon gas seriously, suggesting that genuine risk communication initiatives may have positive impacts on trust in risk management institutions.

A detailed study of inexpensive radon control techniques in New York state houses

International Nuclear Information System (INIS)

Nitschke, I.A.; Wadach, J.B.; Clarke, W.A.; Traynor, G.W.; Adams, G.P.; Rizzuto, J.E.

1984-01-01

As part of a comprehensive indoor air quality and infiltration field study, radon concentrations were measured in 60 houses in upstate New York using passive integrating monitors. Indoor air radon concentrations ranged from 0.2 pCi/l to 50 pCi/l. Four houses with the highest radon levels were then extensively monitored using real-time continuous instruments for the measurement of radon, radon daughters, respirable particles, infiltration, inside-outside pressure difference, and weather parameters. Several inexpensive radon mitigation techniques were tested in these four houses. Their effectiveness ranged widely. Techniques identified as effective were permanently installed in 14 houses having indoor air radon concentration above 2 pCi/l. Finally, the long-term effectiveness of the installed control techniques is being tested using passive integrating radon monitors. (Author)

Determination of Radon-222 and Thoron Concentration in Decorative Stone Warehouses Indoor Air and the Received Effective Dose by Staff

Directory of Open Access Journals (Sweden)

Amir Hossein Mahvi

2015-06-01

Full Text Available Background: Radon is a colorless, odorless, and radioactive gas that can be emitted from decorative stones such as granite, marble, etc. Inhaling radon gas in a long period may cause for incidence of lung cancer among peoples. Material and Methods: In this cross-sectional descriptive study, Radon 222 and Thoron concentrations in background and indoor air were measured in four decorative stones warehouse using portable radon meter(RTM1688-2 model. Totally, 24 samples of 24- hours concentrations in indoor air and 24 samples of 4-hours concentrations of Radon 222 and thoron in the background air at three stages were measured. Then, received effective dose of Radon 222 and Thoron was calculated by UNSCEAR equations. Results: The mean radon concentrations for indoor and background air were 74±37 and 34±16 Bq/m3, respectively. The mean radon concentrations for indoor air in decorative stones warehouses for DSW1, DSW2, DSW3 and DSW4 were 72.50±34, 98.25±43, 34.42±18 and 88.92±51 Bq/m3, respectively. The received effective dose mean of Radon 222 and Thoron by the staff at 8 working hours was 0.53±0.18 and 0.05±0.03 mSv/y and in 16 working hours was 1.05±0.36 and 0.11±0.07 mSv/y, respectively. Generally, the mean received effective dose by staff from Radon at 8 and 16 working hours was 0.58±0.2  and 1.16±0.41 mSv/y, respectively. Conclusions: Radon concentration mean in indoor air and the received effective dose mean by staff was lower than the standards level. Decorative stone warehouses were the resources for accumulation of Radon gas that can be reduced by corrective actions.

Contribution of 222Rn-bearing water to indoor radon and indoor air quality assessment in hot spring hotels of Guangdong, China

International Nuclear Information System (INIS)

Song Gang; Wang Xinming; Chen Diyun; Chen Yongheng

2011-01-01

This study investigates the contribution of radon ( 222 Rn)-bearing water to indoor 222 Rn in thermal baths. The 222 Rn concentrations in air were monitored in the bathroom and the bedroom. Particulate matter (PM, both PM 10 and PM 2.5 ) and carbon dioxide (CO 2 ) were also monitored with portable analyzers. The bathrooms were supplied with hot spring water containing 66-260 kBq m -3 of 222 Rn. The results show that the spray of hot spring water from the bath spouts is the dominant mechanism by which 222 Rn is released into the air of the bathroom, and then it diffuses into the bedroom. Average 222 Rn level was 110-410% higher in the bedrooms and 510-1200% higher in the bathrooms compared to the corresponding average levels when there was no use of hot spring water. The indoor 222 Rn levels were influenced by the 222 Rn concentrations in the hot spring water and the bathing times. The average 222 Rn transfer coefficients from water to air were 6.2 x 10 -4 -4.1 x 10 -3 . The 24-h average levels of CO 2 and PM 10 in the hotel rooms were 89% and 22% higher than the present Indoor Air Quality (IAQ) standard of China. The main particle pollutant in the hotel rooms was PM 2.5 . Radon and PM 10 levels in some hotel rooms were at much higher concentrations than guideline levels, and thus the potential health risks to tourists and especially to the hotel workers should be of great concern, and measures should be taken to lower inhalation exposure to these air pollutants. - Highlights: → 222 Rn-bearing water is the main contributor to indoor radon in hot spring hotel. → The PM 2.5 and CO 2 are also the main indoor pollutants in the hotel rooms. → Higher radon and PM levels might have significant negative health effects to human. → The radon transfer coefficients are consistent with the published data.

Radon level and radon effective dose rate determination in Moroccan dwellings using SSNTDs

International Nuclear Information System (INIS)

Oufni, L.; Misdaq, M.A.; Amrane, M.

2005-01-01

Inhalation of radon ( 222 Rn) and its daughter product are a major source of natural radiation exposure. The measurement of radon activity in dwelling is assuming ever increasing importance. It is known from recent surveys in many countries that radon and its progeny contribute significantly to total inhalation dose and it is fairly established that radon when inhaled in large quantity causes lung disorder. Keeping this in view, the indoor radon activity level and radon effective dose rate were carried out in the dwellings of Beni-Mellal, Khouribgra and Ben Guerir cities, Morocco, using the solid state nuclear track detectors (SSNTD) technique. Assuming an indoor occupancy factor of 0.8 and 0.4 for the equilibrium factor of radon indoors, we found that the 222 Rn effective dose rate in the studied dwellings ranges from 1.01 to 7.90mSvy -1 . The radon activity in the corresponding dwellings was found to vary from 40 to 532Bqm -3 . The radon activity has not only been found to vary with seasonal changes, but also with the age, the construction mode of houses, the ventilation conditions and with specific sites and geological materials

Quantitative aspects of highly emanating geologic materials and their role in creating high indoor radon. Final report, April 1, 1994--March 31, 1996

International Nuclear Information System (INIS)

Gundersen, L.C.S.; Schumann, R.R.; Gates, A.E.; Price, P.

1996-01-01

Indoor radon hot spots, areas where indoor radon commonly exceeds 20 pCi/L, are often caused by unusually highly emanating soils or rock and their interaction with ambient climatic conditions and a building's architecture. Highly emanating soils and rocks include glacial deposits; dry fractured clays; black shales; limestone-derived soils; karst and cave areas, fractured or sheared granitic crystalline rocks; mine tailings; uraniferous backfill; and most uranium deposits. The above list probably accounts for 90% of the Nation's indoor radon over 20 pCi/L. In several of these high indoor radon areas, there appears to be a link between the nature of the radon source in the ground, the architecture of the home, and the relative magnitude and ease of mitigation of the indoor air problem. Quantification of geologic materials in terms of their radon potential with respect to climatic and architectural considerations has never been accomplished. Recent studies have attempted semi-quantitative rankings but rigorous analysis has not been done. In this investigation the authors have attempted to develop the quantitative aspects of geologic materials for prediction of very high indoor radon at several scales of observation from national to census tract

Health effects of exposure to indoor radon and its decay products

International Nuclear Information System (INIS)

Mustafa, A.A.; Vasisht, C.M.

1987-01-01

Estimates of possible incidence of lung cancer associated with present exposure to natural indoor radon are assessed for Kuwait. Several dosimetric models were used and their results are compared. Some models took into consideration individual differences in sex, life-style and age. The UNSCEAR model gives life-time risk values of 2-4.5 x 10 -4 per WLM for miners. Taking into account a factor of 0.6 between the mean breathing rate of workers in the model and non-miners, and the population of Kuwait as 1.7 million, the model gives 46-105 lung cancer cases per year induced by radon and its decay products. Since these models are developed for smokers they tend to overestimate the actual incidence rates. Assuming that 20% of the population in Kuwait are smokers, the incidence rates range will be reduced to 30-63 cases per year which is about 9-20% of the observed lung cancer incidence in 1982. The energy conservation programme is expected to increase average indoor radon concentrations, and consequently bring about higher lung cancer incidence. (author)

Indoor radon

International Nuclear Information System (INIS)

1997-12-01

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

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

International Nuclear Information System (INIS)

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

2000-01-01

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

Overview of current radon and radon daughter research at LBL

International Nuclear Information System (INIS)

1983-01-01

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

Radon in a Karstic Region School: Concentrations in Soil Gas and Indoors

International Nuclear Information System (INIS)

Vaupotic, J.; Kobal, I.; Barisic, D.; Lulic, S.

1998-01-01

The school presented in this paper exceeded instantaneous indoor radon concentration of 1000 Bqm -3 , obtained within the Slovene radon programme. Thus, additional measurements were performed and the radiation doses of teachers and pupils estimated. Radon concentrations between 1000 and 3000 Bqm -3 during teaching hours were found and the yearly effective doses from 0.75 to 1.1 mSv for the pupils and from 1.1 to 4.2 mSv for the teachers were calculated. In the soil gas radon and thoron concentration ranging from 70 to 150 kBqm -3 were obtained. The school was mitigated during summer 1998. (author)

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

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

International Nuclear Information System (INIS)

1991-06-01

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

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

International Nuclear Information System (INIS)

1991-09-01

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

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

International Nuclear Information System (INIS)

1992-01-01

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

Radon Activity measurements in Drinking Water and in Indoors of Dwellings of Dwellings, using RAD7

International Nuclear Information System (INIS)

Mehra, R.; Badhan, K.; Sonkawade, R.G.

2011-01-01

The purpose of this study is to investigate the radon levels of groundwater being used for drinking and indoor radon levels in the environs of villages/towns of Hoshiarpur district of Punjab, India, to determine the health hazards. Radon concentrations in the collected water samples were measured with RAD7 an electronic radon detector connected to a RAD- H 2 O accessory (Durridge Co., USA). In the setup, the RAD7 detector was used for measuring radon in water by connecting it with a bubbling kit which enables to degas radon from a water sample into the air in a closed loop. A sample of water was taken in a radon-tight reagent bottle of 250 ml capacity connected in a close circuit with a zinc sulphide coated detection chamber which acts as scintillator to detect alpha activity and a glass bulb containing calcium chloride to absorb the moisture. Air was then circulated in a closed circuit for a period of 5-10 min until the radon was uniformly mixed with the air and the resulting alpha activity was recorded and it directly gives the radon concentration. The measured radon concentration in drinking water ranges from 2.03 BqL -1 to 6.65 BqL -1 with an average value of 4.27 BqL -1 . The measured values of radon concentration in drinking water are well within the range (4 to 40 BqL -1 ) suggested for radon concentration in water for human consumption by the United Nations Scientific Committee on the Effects of Atomic Radiation. The measured values of indoor radon concentration in dwellings of the same area vary from 10 Bqm -3 to 28.2 Bqm -3 with an average value of 20.28 Bqm -3 . The measured values for drinking water and for indoor air for the study area suggest that the area is safe for residents and there is no significant threat to the population as per as radon concentration is concerned

Factors controlling indoor radon levels. Annual report, June 1983-May 1984

International Nuclear Information System (INIS)

Harley, N.H.

1984-01-01

The factors which contribute to indoor radon levels were investigated. Soil moisture content appears to be such a factor and influences indoor radon levels in a subtle way. The single family dwelling studied here is a typical suburban home, with a full basement, two living levels and a full attic. Seasonal data for 1981 to 1983 are shown by hour (about 90 hours in each average) for the basement, first floor and outdoors. A twenty-five story, 225 apartment, high rise building has been under study for about the same time interval. The apartment has five rooms, and is on the 24th floor. Continuous monitors are located in a work room and outdoors on a terrace. Data are available from the summer of 1981. 2 references, 12 figures, 9 tables

Life time fatality risk assessment due to variation of indoor radon concentration in dwellings in western Haryana, India

International Nuclear Information System (INIS)

Kansal, Sandeep; Mehra, Rohit; Singh, N.P.

2012-01-01

Indoor radon measurements in 60 dwellings belonging to 12 villages of Sirsa, Fatehbad and Hisar districts of western Haryana, India, have been carried out, using LR-115 type II cellulose nitrate films in the bare mode. The annual average indoor radon value in the studied area varies from 76.00 to 115.46 Bq m −3 , which is well within the recommended action level 200–300 Bq m −3 (). The winter/summer ratio of indoor radon ranges from 0.78 to 2.99 with an average of 1.52. The values of annual average dose received by the residents and Life time fatality risk assessment due to variation of indoor radon concentration in dwellings of studied area suggests that there is no significance threat to the human beings due to the presence of natural radon in the dwellings. - Highlights: ► The radon concentration values in the dwellings are 2–3 times more than the world average of 40 Bq m −3 . ► These values are lower than the recommended action level of 200–300 Bq m −3 (). ► The annual effective dose is less than the recommended action level of 3–10 mSv per year (). ► The values of life time fatality risk determined for the studied area are within safe standards. ► There is no significant threat to the human beings due to the presence of natural radon in the dwellings.

Contribution of radon and radon daughters to respiratory cancer

International Nuclear Information System (INIS)

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

1986-01-01

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

Indoor radon survey in dwellings of nine cities in the eastern and western provinces of Saudi Arabia

Energy Technology Data Exchange (ETDEWEB)

Abu-Jarad, F.; Fazal-ur-Rehman; Al-Jarallah, M.I.; Al-Shukri, A

2003-07-01

The results of a first phase of an indoor survey in a total of 1610 dwellings distributed in nine cities of the Eastern and the Western provinces of Saudi Arabia are presented. The objective of this radon survey was to obtain representative indoor radon data for seven cities in the Eastern province, Khafji, Hafr Al-Batin, Abqaiq, Qatif, Al-Ahsa, Dammam and Khobar and to compare this with two cities in the Western province, Madina and Taif. So far, detailed radon data is not available for Saudi Arabia; therefore, this radon survey provides a base line for Saudi Arabia in the Radon World Atlas. On average, 200 indoor radon dosemeters were distributed in each city and placed for a period of one year starting from May 2001 to May 2002. The total number of collected dosemeters was 847. A total of 724 houses and 98 schools were covered in this survey. The results of the survey in the cities showed that the overall minimum, maximum and average radon concentrations were 1, 137 and 22 Bq m {sup -3}, respectively. Geometric mean and geometric standard deviations of the radon distribution were found to be 18 and 1.92, respectively. In one of the dwellings in Qatif city, radon concentration, measured by a passive system and then confirmed by an active system, was found to be 535 {+-} 23 and 523 {+-} 22 Bq m {sup -3}, respectively. The result of a radon survey in 98 schools showed that the minimum, maximum and average radon concentrations were 1, 70 and 19 Bq m{sup -3}, respectively. The average radon concentration for each city was also determined. The lowest average radon concentration (8 Bq m{sup -3}) was found in Al-Ahsa while the highest average concentration (40 Bq m {sup -3}) was found in Khafji. (author)

A study of some factors which are related to indoor radon concentrations in Greece

International Nuclear Information System (INIS)

Louizi, A.; Nikolopoulos, D.; Lobotesi, E.; Mavroudaki, E.; Koukouliou, V.K.; Chanioti, M.; Papadimitriou, D.; Yiakoumakis, M.; Proukakis, C.

1997-01-01

The Medical Physics Department of the University of Athens is conducting radon-222 measurements in Greek dwellings. It is well known that the concentration of radon gas indoors, are related to various factors. A study of these factors has started and first results are reported. (authors)

Indoor air radon concentration in schools in Prizren, Kosovo

International Nuclear Information System (INIS)

Bahtijari, M.; Stegnar, P.; Shemsidini, Z.; Kobal, I.; Vaupotic, J.

2006-01-01

Indoor air radon ( 222 Rn) concentrations were measured in spring and winter in 30 rooms of 9 elementary schools and 19 rooms of 6 high schools in Prizren, Kosovo, using alpha scintillation cells. Only in three rooms of elementary schools and four rooms of high schools did winter concentrations exceed 400 Bq m -3 . (authors)

Indoor radon and risk of lung cancer: an epidemiological study in Finland

International Nuclear Information System (INIS)

Ruosteenoja, E.

1991-03-01

The main aim of the present study was to establish whether high radon concentrations in dwellings in Finland had increased the risk of lung cancer. Previous studies had shown an association between the α-active radon daughters and elevated lung cancer risk among miners. Convincing evidence of the risk among the general population exposed to radon indoors was, however, lacking. A descriptive analysis was first conducted in an area in southern Finland with high indoor radon exposure. In 18 rural municipalities this analysis yielded no significant correlation between the average radon exposure and incidence of male lung cancer. A case-control study within a cohort of the same rural population was then designed. The data included 238 male cases of lung cancer diagnosed in 1980-85 and 434 controls (390 smokers and 44 nonsmokers) from the male population. Radon exposure was measured, when possible, in all the dwellings occupied by a case or control in 1950-1975. Measurements were available for the total 25-year period, or for a proportion of it, for 164 cases and 334 controls; for the rest only estimates were available. In spite of the fact that the controls were mainly selected among smokers, the amount smoked still appeared to be the most important lung cancer risk factor in the data, the risk increasing linearly with the quantity of cigarettes smoked in a lifetime. The risk of lung cancer was not associated with the radon exposure level when the whole data were studied. In heavy smokers, however, a positive though not significant, effect on the risk from radon exposure was found. In the range of uncertainty the findings do not conflict with most of those observed among miners or the general population so far. (orig.)

The equivalent doses of indoor radon in some dwellings and enclosed areas in Morocco

International Nuclear Information System (INIS)

Hakam, O.; Choukri, J.; Reyss, L.

2008-01-01

Full text: The principal source of exposure to radiation for public in built-up areas is known to be the inhalation for radon its short-lived daughters.Most of this exposure occurs inside homes,where many hours are spent each day and where the volumic activity of radon is usually higher than outdoors. The compelling effects of radon and its short-lived decay products spread slowly but surely through a wide range of biological problems encountered in such areas as the mortality rates and lung cancer in uranium mines,the results of experimental work with animals, and the discovery of unsually high levels of radon in the living environments of the general population. As a way of prevention, we have measured the volumic activities of indoor radon-222 and we have calculated their effective equivalent dose in some dwellings and enclosed areas in Morocco. The obtained results show that the effective equivalent dose of activities measured indoor dwellings are inferior to the admissible annual limit fixed by ICRP for population, except in two twons situated in regions rich in phosphate deposits where the calculated doses are slightly upper than this limit. The results obtained for enclosed areas are inferior to the admissible annual limit fixed by ICRP for workers, except in the cave of geophysical observatory situated at depth of-12 meters where the obtained value don't present in risk for workers health because workers pass only a few minutes by day in this cave. The risks related to the volumic activities for indoor radon could be avoided by simple precautions such the continuous ventilation

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)

Investigation of indoor radon concentration in block houses in Omderman

International Nuclear Information System (INIS)

Ahmed, H. A. M.

2010-12-01

Radon is one of the naturally occurring radioactive elements in the environment as a member of the natural uranium decay. Exposure to radon in the home and workplace is one of the main risks of ionizing radiation thought to cause tens of thousands of deaths from lung cancer each year. In order to reduce this burden it is important that national authorities have methods and tools bases on solid scientific evidence and sound public health policy. The public needs to be aware of radon risks and the means to reduce and prevent these. This study presents of the studies dealing with the investigation of exposure from ionizing radiation. The radon levels in some selected type of building styles (Bricks Albulk) were investigated in Omderman city (public housing). The radon level in most of the houses found to range between 87.63 and 206 Bq/m 3 with average value of 127±23 Bq/m 3 . This is well lay within the allowable limit with average. The study indicates that building materials used does not add significant concentration of radon to indoor. It can be considered as safe type of building style from radiation protection point of view. (Author)

Reduction of radon from household water supplies

International Nuclear Information System (INIS)

Shapiro, P.S.; Sorg, T.J.

1988-01-01

Groundwater can be a major source of indoor radon in homes that use individual wells or are served by very small community water supply systems. In the United States, several wells have been found to contain more than 37,000,000 Bq.m -3 of radon dissolved in the water. This radon can be released in the indoor air in the course of using water for normal household activities. A measurement of the radon in the drinking water can be made when an indoor radon problem is suspected. While ventilation may reduce indoor radon levels that result from household water usage, the most common control technique presently applied is removing the radon from the water using a granular activated carbon (GAC) treatment system. Aeration methods are also effective and have been proven to be economical for small community water supplies. Some of the issues faced in using GAC are sizing and maintaining the unit and shielding and disposing of the GAC to prevent exposure from gamma radiation. (author)

Predicted indoor radon concentrations from a Monte Carlo simulation of 1 000 000 granite countertop purchases

International Nuclear Information System (INIS)

Allen, J G; Zwack, L M; MacIntosh, D L; Minegishi, T; Stewart, J H; McCarthy, J F

2013-01-01

Previous research examining radon exposure from granite countertops relied on using a limited number of exposure scenarios. We expanded upon this analysis and determined the probability that installing a granite countertop in a residential home would lead to a meaningful radon exposure by performing a Monte Carlo simulation to obtain a distribution of potential indoor radon concentrations attributable to granite. The Monte Carlo analysis included estimates of the probability that a particular type of granite would be purchased, the radon flux associated with that type, the size of the countertop purchased, the volume of the home where it would be installed and the air exchange rate of that home. One million countertop purchases were simulated and 99.99% of the resulting radon concentrations were lower than the average outdoor radon concentrations in the US (14.8 Bq m −3 ; 0.4 pCi l −1 ). The median predicted indoor concentration from granite countertops was 0.06 Bq m −3 (1.59 × 10 −3 pCi l −1 ), which is over 2000 times lower than the US Environmental Protection Agency’s action level for indoor radon (148 Bq m −3 ; 4 pCi l −1 ). The results show that there is a low probability of a granite countertop causing elevated levels of radon in a home. (paper)

Evaluation of radon concentration in dwellings and well water of Parana State-Brazil

International Nuclear Information System (INIS)

Correa, Janine Nicolosi

2011-01-01

Considering the growing interest of International Agencies and national Governmental organs in studies and measurements of radon activity in air, soil gas and ground water (mainly from artesian wells) as well as scarceness of such measurements at Brazilian territory, present studies were initiated by the Laboratory of Applied Nuclear Physics of Federal University of Technology - Parana (UTFPR) in collaboration with the Institute of Radiation Protection and Dosimetry (IRD) and the Center of Nuclear Technology Development (CDTN) of Brazilian Commission on Nuclear Energy (CNEN). This Collaboration started in 2003. Radon monitoring program is based mainly on use of Solid State Nuclear Track Detectors for radon activity measurements in air. Continuous electronic radon detectors are used for radon measurements in soil gas and water. Current work presents the results of indoor 222 Rn activity of dwellings and working places of Curitiba-PR and radon concentration in ground water samples from artesian wells from aquifers of the same area. The indoor measurements of radon activity were performed using Solid State Nuclear Track Detectors CR-39. After the exposition, CR-39 detectors were submitted to chemical development which permitted to make alpha particle tracks counting. The results of calibration of CR-39 together with efficiency of used exhalation chambers as well as alpha particle tracks chemical development procedure were performed in cooperation with CDTN and collaboration with the National Institute of Radiological Sciences (NIRS). The major part of indoor 222 Rn concentration in residences was found below 100 Bq/m3. In the case of working places, all measurements present 222 Rn concentration bellow 100 Bq/m3. The studies of radon activity in water were performed using the samples of water from artesian wells submitted to recursive measurements by instant radon detector AlphaGUARD PQ2000 PRO during few weeks with intervals of about 4 days between each measurement

Indoor radon measurements in Finland: A status report

International Nuclear Information System (INIS)

Castren, O.; Makelainen, I.; Winqvist, K.; Voutilainen, A.

1987-01-01

Large-scale surveys indicate that the mean indoor radon concentration in Finnish dwellings is about 90 Bq/m/sup 3/. The percentages of concentrations exceeding 200, 400, 800 and 2,000 Bq/m/sup 3/ are 11, 3.9, 1.4 and 0.5 per cent, respectively. An updated version of the geographical distribution is presented. Sampling and data processing methods as well as the reasons for high concentrations are discussed

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

Study of indoor radon levels in some radioactive areas of Himachal Pradesh: an inter-comparison of active and passive techniques

International Nuclear Information System (INIS)

Bajwa, B.S.; Singh, S.; Sharma, N.; Virk, H.S.

2006-01-01

Full text of publication follows: Indoor radon levels measurements were carried using both the active and passive techniques in the dwellings of some villages, known to be located in the vicinity of uranium mineralized zones of Hamirpur district, Himachal Pradesh. Even in the passive technique using S.S.N.T.D., both the bare -slide and twin chamber dosemeter cup modes were utilized. An attempt has also been made to assess the levels of the indoor radon in these dwellings and inhalation dose rates of the population living in these villages. The average value of radon concentration levels using the bare-slide mode varies from 109.0 to 741.5 Bq/m3 in these dwellings, where as the maximum radon level using the twin cup dosemeter technique was found to be 140.3 Bq/m3. As usual the radon concentrations were found to be varying with seasonal changes, building materials etc. The radon survey in the dwellings of these villages has also been carried out using the Alpha-Guard technique, which is based on the pulse ionization chamber. The indoor radon concentration levels measured using the active technique of Alpha Guard have been found to be quite different from those measured in these dwellings by the passive technique of S.S.N.T.D.; indicating the importance of the S.S.N.T.D. in the long -term integrated measurement of the indoor radon levels in the dwellings. (authors)

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.

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)

LIFETIME LUNG CANCER RISKS ASSOCIATED WITH INDOOR RADON EXPOSURE BASED ON VARIOUS RADON RISK MODELS FOR CANADIAN POPULATION.

Science.gov (United States)

Chen, Jing

2017-04-01

This study calculates and compares the lifetime lung cancer risks associated with indoor radon exposure based on well-known risk models in the literature; two risk models are from joint studies among miners and the other three models were developed from pooling studies on residential radon exposure from China, Europe and North America respectively. The aim of this article is to make clear that the various models are mathematical descriptions of epidemiologically observed real risks in different environmental settings. The risk from exposure to indoor radon is real and it is normal that variations could exist among different risk models even when they were applied to the same dataset. The results show that lifetime risk estimates vary significantly between the various risk models considered here: the model based on the European residential data provides the lowest risk estimates, while models based on the European miners and Chinese residential pooling with complete dosimetry give the highest values. The lifetime risk estimates based on the EPA/BEIR-VI model lie within this range and agree reasonably well with the averages of risk estimates from the five risk models considered in this study. © Crown copyright 2016.

Radon gas. A review with emphasis on site investigations and measurements of soil gas and indoor house levels

International Nuclear Information System (INIS)

Mitchell, Seamus.

1992-09-01

A review of radon gas, with particular reference to its source and transport through soils and into buildings is examined. The principal parameters affecting the movement of radon has been discussed. The levels of radon gas in soils and in dwelling houses has been examined. Radon levels in the soil gas were highest in mineral soils with pear soils giving low readings but there was no significant differences between the results. Houses situated over granite and limestone bedrock gave similar results for indoor radon concentrations, with no significant differences being recorded. Results were expected to be much higher in houses over granite areas, in view of the higher uranium series activity in granites. It is concluded that high radon gas levels in soils under and in he vicinity of houses is the probable explanation for the indoor radon levels found. The influence of the underlying bedrock is not the most important parameter as was surmised before the study. (author)

Community-Based Investigation of Radon and Indoor Air Quality in Northeast Denver Neighborhoods

Science.gov (United States)

Pfotenhauer, D.; Iwasaki, P. G.; Ware, G. E.; Collier, A.; Hannigan, M.

2017-12-01

In 2015, Taking Neighborhood Health to Heart (TNH2H), a community-based organization based in Northeast Denver, and researchers from the University of Colorado, Boulder jointly piloted a project to investigate indoor air quality within Denver communities. This pilot study was carried out across 2015-2016 and found higher than actionable-levels for radon across a majority of its participants. These results inspired a continued collaboration between the community group and academic researchers from CU Boulder. The partnership went on to conduct a similar project this last year in which the team again employed a community-based participatory research (CBPR) framework to investigate indoor air pollutants across a broader geographical footprint in Denver's Northeast Neighborhoods. The collaboration sampled 30 participant houses across 5 neighborhoods for radon and volatile organic compounds (VOCs). Although VOC levels were found to be well under thresholds for concern, for the second year of this investigation, radon levels were found on average to be significantly above the EPA's threshold for hazardous levels. Additionally, in collecting survey data on the participants' house characteristics, certain identifiable trends emerged that signal which house types have greater risk of radon intrusion. Having found in two consecutive studies that a majority of homes in these neighborhoods are burdened with dangerous levels of radon, the partnership is now moving towards developing educational and political actions to address the results from these projects and disseminate the information regarding radon levels and threats to these neighborhood communities.

Assessments of activated carbon prepared from date stones in adsorption of indoor radon

International Nuclear Information System (INIS)

Abudaia, J.I.; Al-Ezzaby, Suliman M.; Dawad, E.; Alawar, A.; Al-Shreide, A.

2015-01-01

Radiochemical department (RCD) at Tajoura Nuclear Research Center (TNRC) in Tripoli city is one of the fewest workplaces which have experienced indoor level evaluation. In this present study, it is intended to investigate the efficiency of domestic activated carbons (AC) derived from most locally available agricultural by products date stones (DS) in the adsorption of indoor radon-222 (' 222 Rn) at different oriented sites of RCD. The average indoor radon concentration values in the study areas varied from (34±3.0) Bq/m 3 to (192.7±9.1) Bq/m 3 , while the values of the annual effective dose varied from (0.355) mSv/y to (0.974) mSv/y. All obtained values were within the recommended action levels of (200 - 300) Bq/m 3 and 2.4 mSv/y which are given by International Commission on Radiological Protection (ICRP) in 1993 and 1987 respectively. A designed set up of portable ACDS canisters are proposed to be utilized in other different workplaces such as schools, where educational buildings are considered as locations of ventilation deficiency and high occupancy times for children and such naturally occurring radio-active radon is distinguished as a second leading cause of lung cancer worldwide.(author)

Shelter and indoor air in the twenty-first century: Radon, smoking and lung cancer risks

International Nuclear Information System (INIS)

Fabrikant, J.I.

1988-04-01

This document describes the relationship between indoor radon exposure, cigarette smoking, and lung cancer. The author explains the sources of radon, the tissues at risk, the human populations most likely to be affected, and the estimates of lung cancer in the population. 6 refs., 2 tabs

Hierarchical modeling of indoor radon concentration: how much do geology and building factors matter?

Science.gov (United States)

Borgoni, Riccardo; De Francesco, Davide; De Bartolo, Daniela; Tzavidis, Nikos

2014-12-01

Radon is a natural gas known to be the main contributor to natural background radiation exposure and only second to smoking as major leading cause of lung cancer. The main concern is in indoor environments where the gas tends to accumulate and can reach high concentrations. The primary contributor of this gas into the building is from the soil although architectonic characteristics, such as building materials, can largely affect concentration values. Understanding the factors affecting the concentration in dwellings and workplaces is important both in prevention, when the construction of a new building is being planned, and in mitigation when the amount of Radon detected inside a building is too high. In this paper we investigate how several factors, such as geologic typologies of the soil and a range of building characteristics, impact on indoor concentration focusing, in particular, on how concentration changes as a function of the floor level. Adopting a mixed effects model to account for the hierarchical nature of the data, we also quantify the extent to which such measurable factors manage to explain the variability of indoor radon concentration. Copyright © 2014 Elsevier Ltd. All rights reserved.

Lung cancer attributable to indoor radon exposure in France using different risk models

International Nuclear Information System (INIS)

Catelinois, O.C.; Laurier, D.L.; Rogel, A.R.; Billon, S.B.; Tirmarche, M.T.; Hemon, Dh.; Verger, P.V.

2006-01-01

Full text of publication follows: Radon exposure is omnipresent for the general public, but at variable levels, because radon mainly comes from granitic and volcanic subs oils as well as from certain construction materials. Inhalation of radon is the main source of exposure to radioactivity in the general population of most countries. In 1988, the International Agency for Research on Cancer declared radon to be carcinogenic for humans (lung cancer): radon is classed in the group 1. The exposure of the overall general population to a carcinogenic component led scientists to assess the lung cancer risk associated to indoor radon. The aim of this work is to provide the first lung cancer risk assessment associated with indoor radon exposure in France, using all available epidemiological results and performing an uncertainty analysis. The number of lung cancer deaths potentially associated with radon in houses is estimated for the year 1999 according to several dose-response relationships which come from either cohorts of miners or joint analysis of residential case-controls studies. The variability of indoor radon exposure in France and uncertainties related to each of the dose-response relationships are considered. The assessment of lung cancer risk associated with domestic radon exposure considers 10 dose-response relationships resulting from miners cohorts and case-control studies in the general population. A critical review of available data on smoking habits has been performed and allowed to consider the interaction between radon and tobacco. The exposure data come from measurements campaigns carried out since the beginning of the 1980's by the Institute for Radiation protection and Nuclear Safety and the Health General Directory in France. The French lung cancer mortality data are provided by the INSERM. Estimates of the number of attributable cancers are carried out for the whole country, stratified by 8 large regions and b y 96 departments for the year 1999

Indoor radon concentration levels in Mexican caves, using nuclear track methodology, and the relationship with living habits of the bats

International Nuclear Information System (INIS)

Espinosa, G.; Golzarri, J.I.; Vega-Orihuela, E.; Morales-Malacara, J.B.

2013-01-01

This work presents the results of a study of the radon levels in four caves in Mexico: Los Riscos Cave and El Judio Cave in the State of Queretaro, and Coyozochico Cave and Karmidas Cave in the State of Puebla. The measurements were made using the passive closed-end cup system, with CR-39 (Lantrack R ) as detection material, and following protocols established for the measurement of indoor radon, developed at the Dosimetry Applications Project of the Physics Institute of the Universidad Nacional Autonoma de Mexico. The radon concentration at one location with Karmidas Cave reached more than 60,000 Bq/m 3 , while concentrations in the other three caves varied from 83.1-1216.0 Bq/m 3 , was found. During the study was observed an interesting coincidence between the radon concentration distribution inside the caves, and the bat colonies location. In general, the bat colonies are located at the medium or low radon concentration levels zones. (author)

Contribution of {sup 222}Rn-bearing water to indoor radon and indoor air quality assessment in hot spring hotels of Guangdong, China

Energy Technology Data Exchange (ETDEWEB)

Song Gang, E-mail: songg2005@126.co [School of Environmental Science and Engineering, Guangzhou University, Guangzhou 510006 (China); Wang Xinming [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Chen Diyun; Chen Yongheng [School of Environmental Science and Engineering, Guangzhou University, Guangzhou 510006 (China)

2011-04-15

This study investigates the contribution of radon ({sup 222}Rn)-bearing water to indoor {sup 222}Rn in thermal baths. The {sup 222}Rn concentrations in air were monitored in the bathroom and the bedroom. Particulate matter (PM, both PM{sub 10} and PM{sub 2.5}) and carbon dioxide (CO{sub 2}) were also monitored with portable analyzers. The bathrooms were supplied with hot spring water containing 66-260 kBq m{sup -3} of {sup 222}Rn. The results show that the spray of hot spring water from the bath spouts is the dominant mechanism by which {sup 222}Rn is released into the air of the bathroom, and then it diffuses into the bedroom. Average {sup 222}Rn level was 110-410% higher in the bedrooms and 510-1200% higher in the bathrooms compared to the corresponding average levels when there was no use of hot spring water. The indoor {sup 222}Rn levels were influenced by the {sup 222}Rn concentrations in the hot spring water and the bathing times. The average {sup 222}Rn transfer coefficients from water to air were 6.2 x 10{sup -4}-4.1 x 10{sup -3}. The 24-h average levels of CO{sub 2} and PM{sub 10} in the hotel rooms were 89% and 22% higher than the present Indoor Air Quality (IAQ) standard of China. The main particle pollutant in the hotel rooms was PM{sub 2.5}. Radon and PM{sub 10} levels in some hotel rooms were at much higher concentrations than guideline levels, and thus the potential health risks to tourists and especially to the hotel workers should be of great concern, and measures should be taken to lower inhalation exposure to these air pollutants. - Highlights: {yields} {sup 222}Rn-bearing water is the main contributor to indoor radon in hot spring hotel. {yields} The PM{sub 2.5} and CO{sub 2} are also the main indoor pollutants in the hotel rooms. {yields} Higher radon and PM levels might have significant negative health effects to human. {yields} The radon transfer coefficients are consistent with the published data.

Investigation of indoor radon concentration in block houses in Omderman

Energy Technology Data Exchange (ETDEWEB)

Ahmed, H A. M. [Atomic Energy Council, Sudan Academy of Sciences (SAS), Khartoum (Sudan)

2010-12-15

Radon is one of the naturally occurring radioactive elements in the environment as a member of the natural uranium decay. Exposure to radon in the home and workplace is one of the main risks of ionizing radiation thought to cause tens of thousands of deaths from lung cancer each year. In order to reduce this burden it is important that national authorities have methods and tools bases on solid scientific evidence and sound public health policy. The public needs to be aware of radon risks and the means to reduce and prevent these. This study presents of the studies dealing with the investigation of exposure from ionizing radiation. The radon levels in some selected type of building styles (Bricks Albulk) were investigated in Omderman city (public housing). The radon level in most of the houses found to range between 87.63 and 206 Bq/m{sup 3} with average value of 127{+-}23 Bq/m{sup 3}. This is well lay within the allowable limit with average. The study indicates that building materials used does not add significant concentration of radon to indoor. It can be considered as safe type of building style from radiation protection point of view. (Author)

Radon concentration as an indicator of the indoor air quality: development of an efficient measurement method

International Nuclear Information System (INIS)

Roessler, F.A.

2015-01-01

Document available in abstract form only. Full text of publication follows: Energy conservation regulation could lead to a reduction of the air exchange rate and also a degradation of the indoor air quality. Present methods for the estimating the indoor air quality can only be implemented with limitations. This paper presents a method that allows the estimation of the indoor air quality under normal conditions by using natural radon as an indicator. With mathematical models, the progression of the air exchange rate is estimated by using the radon concentration. Furthermore, the progression of individual air pollutants is estimated. Through series of experiments in a measurement chamber, the modelling could be verified. (author)

Radon level in China and elevated indoor exposure in carbon brick and cave dwellings

International Nuclear Information System (INIS)

Wang Zuoyuan

1992-01-01

A nation wide survey of Chinese houses was conducted to determine the average annual effective dose to Chinese population from exposure to radon and its daughter products. The indoor and outdoor concentrations of radon and its daughters were measured using scintillation flask, two filter and carbon canister methods, as well as modified Tsivoglou methods for Rn daughters. Average Rn concentrations are 26.2Bqm -3 and 13.5Bqm -3 for indoor and outdoor environment, respectively. Potential alpha energy concentration, indoor is 744 x 10 -10 Jm -3 , outdoor is 511 x 10 -10 Jm -3 . Equilibrium Factor of Rn daughters are 0.49 (indoor) and 0.61 (outdoor). Occupancy Factor is 0.77 and 0.23. Using appropriate conversion factors, the annual average effective dose to Chinese population is 0.967 mSv. And also, the indoor Rn concentration and gamma dose rate were surveyed in two rural Provinces: Gansu and Jianxi. The fact was found that lung cancer mortality of population lived in high Rn level dwellings is higher than in control groups. An epidemiological retrospective case-control study is recommended in houses with high Rn level. (author)

Radon Concentration in Outdoors and Indoors Around the Flare in Oil Mine Sites

International Nuclear Information System (INIS)

Sutarman; Wahyudi; Luhantara

2003-01-01

The flares are much found at the oil exploration areas which appear the combustion gases emission to the environment that pass through a pipe at about 8 m high from the ground level. The flare is released into the environment together with the hydrocarbon and radon gases. This study has been carried out the measurement of the radon gas concentration only. Radon is a radioactive gas which comes from the natural radioactive decay of uranium ( 238 U). The outdoor radon concentrations were measured in 23 locations with the two-filter method. The locations were determined by a circle which the flare as the point center. The outdoor radon concentrations were measured in 74 houses (more than distance of 600 m from the flare) with the alpha track detector (CR-39) placed in the living rooms for about three months. The measurements of the radon concentrations were carried out in Cepu, Cirebon, and Prabumulih oil mine sites. The results showed that the outdoor radon concentrations a range of 108 Bq/m 3 to 256 Bq/m 3 in Cepu, 248 Bq/m 3 to 3525 Bq/m 3 in Cirebon, and 51 Bq/m 3 to 114 Bq/m 3 in Prabumulih. The results showed that the indoor radon concentrations a range of 11 Bq/m 3 to 38 Bq/m 3 in Cepu, 28 Bq/m 3 to 184 Bq/m 3 in Cirebon, and 12 Bq/m 3 to 38 Bq/m 3 in Prabumulih. The data of the maximum radon concentration in outdoor air was higher than an actual level which recommended by International Atomic Energy Agency (IAEA) for workplaces. The maximum radon concentration in indoor air was lower than an actual level which recommended by IAEA for dwellings. IAEA recommends the actual level of 1000 Bq/m 3 for workplaces and 200 Bq/m 3 for dwellings. These data will be used for the baseline data of the environmental radioactivity in Indonesia. (author)

Improved predictive mapping of indoor radon concentrations using ensemble regression trees based on automatic clustering of geological units

International Nuclear Information System (INIS)

Kropat, Georg; Bochud, Francois; Jaboyedoff, Michel; Laedermann, Jean-Pascal; Murith, Christophe; Palacios, Martha; Baechler, Sébastien

2015-01-01

Purpose: According to estimations around 230 people die as a result of radon exposure in Switzerland. This public health concern makes reliable indoor radon prediction and mapping methods necessary in order to improve risk communication to the public. The aim of this study was to develop an automated method to classify lithological units according to their radon characteristics and to develop mapping and predictive tools in order to improve local radon prediction. Method: About 240 000 indoor radon concentration (IRC) measurements in about 150 000 buildings were available for our analysis. The automated classification of lithological units was based on k-medoids clustering via pair-wise Kolmogorov distances between IRC distributions of lithological units. For IRC mapping and prediction we used random forests and Bayesian additive regression trees (BART). Results: The automated classification groups lithological units well in terms of their IRC characteristics. Especially the IRC differences in metamorphic rocks like gneiss are well revealed by this method. The maps produced by random forests soundly represent the regional difference of IRCs in Switzerland and improve the spatial detail compared to existing approaches. We could explain 33% of the variations in IRC data with random forests. Additionally, the influence of a variable evaluated by random forests shows that building characteristics are less important predictors for IRCs than spatial/geological influences. BART could explain 29% of IRC variability and produced maps that indicate the prediction uncertainty. Conclusion: Ensemble regression trees are a powerful tool to model and understand the multidimensional influences on IRCs. Automatic clustering of lithological units complements this method by facilitating the interpretation of radon properties of rock types. This study provides an important element for radon risk communication. Future approaches should consider taking into account further variables

Effect of local geology on indoor radon levels: a case study

International Nuclear Information System (INIS)

Hawthorne, A.R.; Gammage, R.B.; Dudney, C.S.

1984-01-01

This paper presents the results of radon monitoring in 40 East Tennessee homes that were a component of a larger study to evaluate indoor air quality. Measurements were conducted during two 3-month time periods with passive integrating track etch monitors in each of the forty homes. In a subset of homes, measurements were also conducted with a real-time monitor that provided readings on an hourly basis. The results of the monitoring indicate that about 30% of the homes had radon levels greater that 4 pCi/L in the living space. Homes with elevated radon levels were associated with local variations in geology; most of the homes having higher levels were located on the porous dolomite ridge partially surrounding Oad Ridge, Tennessee. (Author)

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.

Variations of radon volume activities in soil and indoor air and their correlation

International Nuclear Information System (INIS)

Mojzes, A.

1998-01-01

Some manual measurements of volume activity of 222 Rn ai soil air and in indoor air of building together with parallel measurements of some meteorological parameters (temperature, humidity and pressure) of both atmospheric and indoor air were carried out. The measurements were performed in the building of Faculty and in its subsoil which consists of slope loams of the base of SW slopes of granitic Male Karpaty Mountains in the area of confluence of the Vidrica Creek with an arm of the Donau river. The monitoring measurements lasted form more than one and a half year, from January 1977 to August 1998, with the frequency of approximately once a week in each object. The soil air was taken from a permanently set up and sealed pipe from the depth of 0.8 m which was placed approximately 10 m from the building at the open air. All measurements of 222 Rn volume activities were performed with a portable fully automatic scintillation detector based on exchangeable Lucas cells. There were also performed the parallel measurements of some meteorological parameters (temperature, humidity and pressure) of air in each object. The geological basement of building is a source of indoor radon. The volume activities of soil 222 Rn range from about 2 kBq/m 3 to about 20 kBq/m 3 with the average of 9.26 kBq/m 3 and the standard deviation of 2.95 kBq/m 3 . The volume activities of indoor air in basement room were form 150 Bq/m 3 to 225 Bq/m 3 and on the third story they were from 125 Bq/m 3 to 175 Bq/m 3 (approximately). The results of monitoring measurements during 20 months period point out the intensity of interaction of geological substrate with building interior through the values of the volume activity of 222 Rn. Therefore a method of building foundation is one of the most important factors which determines the quantity of radon in indoor air. In the light of quality, the fluctuation of radon presence in the bottom part of the buildings is strongly determined by the variations of

Measurement and comparison of indoor radon levels in new and old buildings in the city of Muzaffarabad (Azad Kashmir), Pakistan. A pilot study

International Nuclear Information System (INIS)

Rafique, Muhammad; Jabeen, Shahida; Bukhari, Shujaht; Rahman, Saeed ur; Shahzad, Muhammad Ikram; Matiullah; Rahman, Said; Nasir, Tabassum

2009-01-01

Indoor radon concentrations have been measured in a limited number of dwellings in the state capital of Azad Jammu and Kashimir, Muzaffarabad city after the devastating earthquake of 2005. Radon detectors (CN-85 based box-type) were placed in the drawing rooms, bedrooms and kitchens of 35 houses, selected on the basis of their location and design as well as willingness and cooperation of householders from mid May to mid July 2007. The average radon concentrations were found to vary from 24 to 518 Bq m -3 , 41 to 380 Bq m -3 and 32 to 467 Bq m -3 in the bedrooms, drawing rooms and kitchens, respectively. The weighted average radon concentration in older houses was found to vary from 51 to 334 Bq m -3 and for newly constructed houses a considerable decrease in measured values (ranging from 14 to 102 Bq m -3 ) have been found. As Pakistan does not currently have a national reference (or action level) for radon in homes, therefore the present data has been compared with the data reported for other countries. Some of the houses studied were found to have higher radon concentrations. These higher values of indoor radon levels may be due to the poor ventilation and influence of the earthquake in creating new fissures and therefore new pathways for radon to enter into the buildings. (author)

Measurement and comparison of indoor radon levels in new and old buildings in the city of Muzaffarabad (Azad Kashmir), Pakistan. A pilot study

Energy Technology Data Exchange (ETDEWEB)

Rafique, Muhammad; Jabeen, Shahida; Bukhari, Shujaht [Dept. of Physics, Univ. of Azad Jammu and Kashmir Muzaffarabad, Azad Kashmir (Pakistan); Rahman, Saeed ur [Dept. of Physics, COMSATS Inst. of Information Technology, Islamabad (Pakistan); Shahzad, Muhammad Ikram; Matiullah, [Physics Division, PINSTECH, Islamabad (Pakistan); Rahman, Said [SPAS Division, SPARCENT, SUPARCO HQs, Karachi (Pakistan); Nasir, Tabassum [Dept. of Physics, Gomal Univ., Dera Ismail Khan (Pakistan)

2009-11-15

Indoor radon concentrations have been measured in a limited number of dwellings in the state capital of Azad Jammu and Kashimir, Muzaffarabad city after the devastating earthquake of 2005. Radon detectors (CN-85 based box-type) were placed in the drawing rooms, bedrooms and kitchens of 35 houses, selected on the basis of their location and design as well as willingness and cooperation of householders from mid May to mid July 2007. The average radon concentrations were found to vary from 24 to 518 Bq m{sup -3}, 41 to 380 Bq m{sup -3} and 32 to 467 Bq m{sup -3} in the bedrooms, drawing rooms and kitchens, respectively. The weighted average radon concentration in older houses was found to vary from 51 to 334 Bq m{sup -3} and for newly constructed houses a considerable decrease in measured values (ranging from 14 to 102 Bq m{sup -3}) have been found. As Pakistan does not currently have a national reference (or action level) for radon in homes, therefore the present data has been compared with the data reported for other countries. Some of the houses studied were found to have higher radon concentrations. These higher values of indoor radon levels may be due to the poor ventilation and influence of the earthquake in creating new fissures and therefore new pathways for radon to enter into the buildings. (author)

Assessment of Indoor Radon (222Rn) Concentrations in the Vicinity of

African Journals Online (AJOL)

MLAY

ABSTRACT. This study aimed to assess indoor radon concentrations in the vicinity of the Manyoni Uranium ... risk of lung cancer proportionally to the ... deposit, power plant, industrial radiation, etc. ... in foundations, walls, hollow concrete .... (AlphaGUARD User Manual 2007). ... used as control are presented in Table 4. The.

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.

Testing of indoor radon-reduction techniques in central Ohio houses: Phase 1 (Winter 1987-1988). Report for October 1987-August 1988 (Final)

International Nuclear Information System (INIS)

Findlay, W.O.; Robertson, A.; Scott, A.G.

1989-07-01

The U.S. Environmental Protection Agency (EPA) has a program to demonstrate practical, cost-effective methods to reduce indoor radon concentrations in housing to 150 Bq/cu m (4 pCi/L) or less. The complete program will evaluate the full range of radon-reduction methods, i.e., house ventilation, sealing of entry routes, soil ventilation, radon removal from water, and air cleaning in the full range of housing substructure types and building styles, and geological conditions across the continental United States. The program described in the report demonstrated certain radon-reduction methods in housing and geology typical of southern Ohio in particular, and the central Great Plains States in general. The testing of radon-mitigation systems in Ohio houses is envisioned as taking place in two phases. The report describes Phase 1, which was carried out in 16 existing houses in the Dayton area during the 1987-1988 heating season

Blower door method in radon diagnostics

International Nuclear Information System (INIS)

Fronka, A.; Moucka, L.

2004-01-01

The idea of the radon transfer factor is commonly presented as the ratio of the building indoor radon concentration to the subsoil radon concentration. Ventilation and the pressure field over the whole building envelope, which varies in a time over a very wide range even in the same building, poses a major problem. Therefore a new approach based on the controlled conditions determining the soil air infiltration was developed. Radon in soil gas infiltrates into the building indoor environment particularly through cracks and other leakages in the structure providing the building contact with its subsoil. The infiltration is driven by the air pressure difference on the two sides of the structure. The pressure difference is caused by the stack effect and its value ranges from 1-2 Pa in family houses to some tens of Pa in higher buildings. Unfortunately, the pressure difference is very unstable under normal conditions, being affected by a host of parameters such as the height of the building, distribution and geometry of leakages, outdoor-indoor temperature difference, etc. Wind direction and velocity of the wind plays a major role. In our research the blower door method was applied in combination with a monitoring of the indoor radon concentration. The indoor-outdoor pressure difference and the pressure difference at the two sides of the screen shutter of the blower door fan are also measured. The blower door ensures a constant, evaluable air exchange rate. The fan power is regulated to provide a stable pressure difference within the range of roughly 5-100 Pa. This approach provides very well defined conditions allowing us to apply a constant ventilation-constant radon supply model. In such circumstances the dynamical changes of radon concentrations are very fast, and therefore a unique continual radon monitor was applied. The radon supply rate is evaluated from the radon steady state of the time course of radon concentration. The dependence of the radon supply rate on

Impact of ventilation systems and energy savings in a building on the mechanisms governing the indoor radon activity concentration.

Science.gov (United States)

Collignan, Bernard; Powaga, Emilie

2017-11-23

For a given radon potential in the ground and a given building, the parameters affecting the indoor radon activity concentration (IRnAC) are indoor depressurization of a building and its air change rate. These parameters depend mainly on the building characteristics, such as airtightness, and on the nature and performances of the ventilation system. This study involves a numerical sensitivity assessment of the indoor environmental conditions on the IRnAC in buildings. A numerical ventilation model has been adapted to take into account the effects of variations in the indoor environmental conditions (depressurization and air change rate) on the radon entry rate and on the IRnAC. In the context of the development of a policy to reduce energy consumption in a building, the results obtained showed that IRnAC could be strongly affected by variations in the air permeability of the building associated with the ventilation regime. Copyright © 2017 Elsevier Ltd. All rights reserved.

Radon in indoor air of primary schools: determinant factors, their variability and effective dose.

Science.gov (United States)

Madureira, Joana; Paciência, Inês; Rufo, João; Moreira, André; de Oliveira Fernandes, Eduardo; Pereira, Alcides

2016-04-01

Radon is a radioactive gas, abundant in granitic areas, such as in the city of Porto at the north-east of Portugal. This gas is a recognized carcinogenic agent, being appointed by the World Health Organization as the leading cause of lung cancer after smoking. The aim of this preliminary survey was to determine indoor radon concentrations in public primary schools, to analyse the main factors influencing their indoor concentration levels and to estimate the effective dose in students and teachers in primary schools. Radon concentrations were measured in 45 classrooms from 13 public primary schools located in Porto, using CR-39 passive radon detectors for about 2-month period. In all schools, radon concentrations ranged from 56 to 889 Bq/m(3) (mean = 197 Bq/m(3)). The results showed that the limit of 100 Bq/m(3) established by WHO IAQ guidelines was exceeded in 92 % of the measurements, as well as 8 % of the measurements exceeded the limit of 400 Bq/m(3) established by the national legislation. Moreover, the mean annual effective dose was calculated as 1.25 mSv/y (ranging between 0.58 and 3.07 mSv/y), which is below the action level (3-10 mSv). The considerable variability of radon concentration observed between and within floors indicates a need to monitor concentrations in several rooms for each floor. A single radon detector for each room can be used, provided that the measurement error is considerably lower than variability of radon concentration between rooms. The results of the present survey will provide useful baseline data for adopting safety measures and dealing effectively with radiation emergencies. In particular, radon remediation techniques should be used in buildings located in the highest radon risk areas of Portugal. The results obtained in the current study concerning radon levels and their variations will be useful to optimize the design of future research surveys.

Health Risk Assessment Induced by Inhalation Radon Content in the Indoor Air of Decorative Stone of Storehouses

Directory of Open Access Journals (Sweden)

Amir Hossein Mahvi

2017-11-01

Conclusions: Mean radon concentration in indoor air and the mean effective dose received by staff is lower than the standards level. Decorative stone of warehouses is the resources accumulation of Radon gas that can be reduced by doing corrective actions. 

Seasonal variation of indoor radon-222 levels in dwellings in Ramallah province and East Jerusalem suburbs, Palestine

International Nuclear Information System (INIS)

Leghrouz, A. A.; Abu-samreh, M. M.; Shehadeh, A. K.

2012-01-01

This study presents the seasonal variations of indoor radon levels in dwellings located in the Ramallah province and East Jerusalem suburbs, Palestine. The measurements were performed during the summer and winter of the year 2006/2007 using CR-39 solid-state-nuclear-track detectors. The total number of investigated buildings is 75 in summer and 81 in winter. A total number of 142 dosemeters are installed in dwellings for each season for a period of almost 100 d. The radon concentration levels in summer varied from 43 to 192 Bq m -3 for buildings in the Ramallah province and from 30 to 655 Bq m -3 for East Jerusalem suburbs. In winter, the radon concentration levels are found to vary from 38 to 375 Bq m -3 in the Ramallah buildings and from 35 to 984 Bq m -3 in East Jerusalem suburbs. The obtained results for radon concentration levels in most places are found to be within the accepted international levels. (authors)

Measurements of the deposition rates of radon daughters on indoor surfaces

International Nuclear Information System (INIS)

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

1982-01-01

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

Characterization of radon levels in indoor air

International Nuclear Information System (INIS)

George, A.C.

1982-01-01

The purpose is to describe the different types of monitoring and sampling techniques that can determine the radiation burden of the general public from radon and its decay products. This is accomplished by measuring the range and distribution of radon and radon decay products through broad surveys using simple and convenient integrating monitoring instruments. For in-depth studies of the behavior of radon decay products and calculation of the radiation dose to the lung, fewer and more intensive and complex measurements of the particle size distribution and respiratory deposition of the radon decay products are required. For diagnostic purposes, the paper describes measurement techniques of the sources and exhalation rate of radon and the air exchange inside buildings. Measurement results form several studies conducted in ordinary buildings in different geographical areas of the United States, using the described monitoring techniques, indicate that the occupants of these buildings are exposed to radon and radon decay product concentrations, varying by as much as a factor of 20

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.

Radon atlas of Finland

International Nuclear Information System (INIS)

Voutilainen, A.; Maekelaeinen, I.; Pennanen, M.; Reisbacka, H.; Castren, O.

1997-11-01

The most efficient means of reducing indoor radon exposure is to locate and mitigate dwellings with radon concentration exceeding the action level of 400 Bq/m 3 and to build new houses so that radon concentrations do not exceed 200 Bq/m 3 . The maps and tables in this report are useful tools for those who plan and decide what kind of radon mitigation measures are needed in municipalities. STUK (The Radiation and Nuclear Safety Authority) has an indoor radon database of 52 000 dwellings, for which the indoor radon concentration and construction details are known. The building site soil type of about 38 000 dwellings is known. This atlas is a summary of all indoor radon measurements made by STUK in lowrise dwellings and in first-floor flats. The results are shown as arithmetic means of 5- or 10-km squares on maps of the provinces. Three radon maps have been made for each province. On one map the data consist of all measurements the position coordinates of which are known. On the two other maps the building sites of houses are classified into permeable and low-permeable soil types. The tables show statistics for all indoor radon measurements by municipality and building site soil type. (orig.)

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

International Nuclear Information System (INIS)

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

1988-06-01

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

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

International Nuclear Information System (INIS)

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

2016-01-01

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

Swiss radon programme 'RAPROS'

International Nuclear Information System (INIS)

Zeller, W.

1992-03-01

The results of the five-year radon research program RAPROS presented in this report, allow for scientifically valid statements on the origin of elevated levels of indoor radon in Switzerland. These results form a basis for recommendations and for actions to be taken. Indoor radon concentrations have been measured in more than 4000 living-rooms and 2000 basements; a sampling density of about 0.2% of the Swiss housing stock. According to these measurements radon leads to an estimated average annual effective dose of 2 milli-Sievert, although in some regions the annual dose may be much higher. Extrapolation of the existing data shows that in about 10'000 Swiss houses radon may exceed 1000 Bq/m 3 . For these houses remedial actions are recommended. There seems to be no radon problem in the large cities in the Swiss Plateau. High indoor radon concentrations in Switzerland are due to the soil beneath the buildings. Data from the study indicated that the most important soil characteristic influencing indoor radon concentrations was its gas permeability. Because natural ventilation in a heated house creates a slight underpressure in the lower levels with respect to surrounding soils, radon is driven from the soil into the building. Weatherization of the houses to reduce energy consumption had in most cases no effect on the indoor radon concentrations. Radon from tap water or from building materials does not contribute significantly to indoor radon levels in Switzerland. The high levels in the Jura Mountains are thought to be associated with karstic limestone bedrock. Several houses within Switzerland have now been modified to reduce radon levels. The most successful mitigation technique combined forced-air ventilation with tightening of the basement to decrease or prevent air infiltration from the soil. (author) figs., tabs., refs

A representative survey of indoor radon in the sixteen regions in Mexico City.

Science.gov (United States)

Espinosa, G; Gammage, R B

2003-01-01

Mexico City, also called Federal District, covers an area of 1504 km(2), and has more than 8 million inhabitants. It is located more than 2200 m above sea level in a zone of high seismic activity, and founded on an ancient lake. At present it is one of the most crowded and contaminated cities in the world, with thermal inversions. Chemical contaminants and aerosol particles in the environmental air are high most of the year. Due to these geological, environmental and socioeconomic conditions, Federal District presents very peculiar characteristics, which are important for understanding the distribution and measurements of indoor radon concentration. In this work the results of 3 year (1998-2000) measurements of indoor radon levels in the Federal District are presented. For the detector distribution and measurements, the actual political administrative divisions of the Federal District, consisting of 16 very well defined zones, was used. Nuclear track detection methodology was selected for the measurement, with a passive device close-end-cup system with CR-39 (Lantrack) polycarbonate as the detection material, with one step chemical etching, following a very well established protocol developed at the Instituto de Física, UNAM. Calibration was carried out at the Oak Ridge National Laboratory, and verification at the Instituto de Física chamber. The results show that the arithmetical mean values of the indoor radon concentration for each region of the Federal District follow a non-homogenous distribution.

A representative survey of indoor radon in the sixteen regions in Mexico City

International Nuclear Information System (INIS)

Espinosa, G.; Gammage, R.B.

2003-01-01

Mexico City, also called Federal District, covers an area of 1504 km 2 , and has more than 8 million inhabitants. It is located more than 2200 m above sea level in a zone of high seismicactivity, and founded on an ancient lake. At present it is one of the most crowded and contaminated cities in the world with thermal inversions. Chemical contaminants and aerosol particles in the environmental air are high most of the year. Due to these geological, environmental and socioeconomic conditions, Federal District presents very peculiar characteristics, which are important for understanding the distribution and measurement zone of high seismic activity of indoor radon concentration. In this work the results of 3 year (1998-2000) measurements of indoor radon levels in the Federal District are presented. For the detector distribution and measurements, the actual political administrative divisions of the Federal District, consisting of 16 very well defined zones was used. Nuclear track detection methodology was selected for the measurement, with a passive device close-end-cup system with CR-39 (Lantrack(r)) polycarbonate as the detection material, with one step chemical etching, following a very well established protocol developed at the Instituto de Fisica, UNAM. Calibration was carried out at the Oak Ridge National Laboratory, and verification at the Instituto de Fisica chamber. The results show that the arithmetical mean values of the indoor radon concentration for each region of the Federal District follow a non-homogeneous distribution. (author)

Low air exchange rate causes high indoor radon concentration in energy-efficient buildings

International Nuclear Information System (INIS)

Vasilyev, A.V.; Yarmoshenko, I.V.; Zhukovsky, M.V.

2015-01-01

Since 1995, requirements on energy-efficient building construction were established in Russian Building Codes. In the course of time, utilisation of such technologies became prevailing, especially in multi-storey building construction. According to the results of radon survey in buildings constructed meeting new requirements on energy efficiency, radon concentration exceeds the average level in early-constructed buildings. Preponderance of the diffusion mechanism of radon entry in modern multi-storey buildings has been experimentally established. The experimental technique of the assessment of ventilation rate in dwellings under real conditions was developed. Based on estimates of average ventilation rate, it was approved that measures to increase energy efficiency lead to reduction in ventilation rate and accumulation of higher radon concentrations indoors. Obtained ventilation rate values have to be considered as extremely low. (authors)

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

Science.gov (United States)

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

Determination of radon in indoor air in Quebec by liquid scintillation counting in ortho-xylene

Energy Technology Data Exchange (ETDEWEB)

Chah, B; Zikovsky, L; Champagne, P [Ecole Polytechnique, Montreal, PQ (Canada)

1992-01-01

A new method for the determination of radon in air has been developed. it is based on low temperature absorption of radon in ortho-xylene followed by liquid scintillation counting. The method is reasonably fast and sensitive enough to analyse air without precipitation. The detection limit at the 95% confidence level for a 20 l air sample and 1 h counting time is 2 mBql{sup -1}. Radon concentrations measured in indoor air in Quebec varied from 7 to 162 mBql{sup -1}. (Author).

www.tjs.udsm.ac.tz www.ajol.info/index.php/tjs/ INDOOR RADON ...

African Journals Online (AJOL)

user

in this study have concentration levels of indoor radon above the reference level of 100 Bq/m3 set by WHO ... MATERIAL AND METHODS. Sample ..... Rates of. Selected Building Materials in Tanzania. ... with a Diverse Pipeline of Projects in.

ROE Radon Data

Data.gov (United States)

U.S. Environmental Protection Agency — The polygon dataset represents predicted indoor radon screening levels in counties across the United States. These data were provided by EPA’s Office of Radiation...

Indoor radon in three similar two-story houses with different ventilation systems

International Nuclear Information System (INIS)

Kokotti, H.; Savolainen, T.; Raunemaa, T.; Kalliokoski, P.

1989-01-01

Radon levels were monitored in three similar two-story apartment houses which were located side by side on a gravel esker in eastern Finland. The houses differed only in regard to their ventilation systems which included the following: natural ventilation, mechanical exhaust, and complete mechanical ventilation. The study started immediately when the houses were finished and was continued for two years. Radon concentrations were highest (60-430 Bq/m 3 ) in the beginning of the study period before the tenants moved in. During the following spring and fall, average radon levels of the houses decreased below 100 Bq/m 3 . Radon concentrations varied within a wide range, from 20 to 230 Bq/m 3 , in the apartments. Among the houses, the highest concentrations were found in the house equipped with mechanical exhaust ventilation and the lowest in the house with both a mechanical supply and exhaust system. One reason for the decreasing levels of radon after a one-year occupancy was that the tenants increased the ventilation of their apartments. In the house with complete mechanical ventilation, the stability of ventilation also contributed to the decrease of the indoor radon level

Potential for ion-induced nucleation of volatile organic compounds by radon decay in indoor environments

International Nuclear Information System (INIS)

Daisey, J.M.

1991-11-01

There is considerable interest in the ''unattached'' fraction of radon progeny in indoor air because of its significance to the estimation of the risks of radon exposure. Because of its high mobility in air, the unattached fraction is more efficiently deposited in the respiratory tract. Variation in the diameter of the ''unattached'' fraction and in its diffusion coefficient can be due to clustering of other atmospheric species around the 218 PoO 2 + ion. The purpose of this study was to investigate the potential for the formation of clusters of vapor phase organic compounds, found in indoor air, around the 218 PoO 2 + ion and to determine which were most likely to form clusters. A secondary purpose was to provide a compilation of measurements of indoor organic compounds for future experiments and theoretical calculations by the radon research community. The classical charged liquid droplet theory (Thomson equation) was used to estimate the Gibbs free energy of ion-induced nucleation and to provide an indication of the indoor organic compounds most likely to undergo ion-induced nucleation. Forty-four volatile and semi-volatile organic compounds out of the more than 300 which have been reported in indoor air were investigated. Water vapor was included for comparison. The results indicate that there is a potential for the formation of clusters of organic compounds around the 218 PoO 2 + ion. The compounds with the greatest potential for cluster formation are the volatile oxidized hydrocarbons (e.g., n-butanol, phenol, hexanal, nonanal, benzaldehyde, the ketones and the acetates) and the semi-volatile organic compounds (pentachlorophenol, nicotine, chlordane, chlorpyrifos)

Radon in Estonian buildings. Establishment of a measurement system and obtained results

International Nuclear Information System (INIS)

Pahapill, L.; Rulkov, A.; Swedjemark, G.A.

1996-12-01

One purpose of this project was the establishment of a radon monitoring programme inside the state environmental monitoring programme. Another purpose was to investigate regions, expected to have high radon levels indoors. A new method for the long-term measurement of indoor radon was established and the staff for these measurements was trained. The results of the measurement can be used by Estonian decision-makers to work out rules and standards. There is no legislative act in the field of radiation in Estonian at this time. To summarize the results of the measurements we can say that indoor radon concentrations vary by region. The radon investigations must be continued to identify the risk areas and types of housing construction. The results of the state radon monitoring are provided to the municipalities, who advice the owners of planned new houses to select the right construction for the house. A new project will follow with an investigation of radon in randomly selected dwellings, training and equipment for radon measurement in soil, and general advice with regard to radon, as well as assistance in preparing information about radon. 7 refs, 5 figs