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Dae Ryong Kang - One of the best experts on this subject based on the ideXlab platform.
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A Deterministic Model for Estimating Indoor Radon Concentrations in South Korea.
International journal of environmental research and public health, 2019Co-Authors: Ji Hyun Park, Cheolmin Lee, Dae Ryong KangAbstract:Estimating long-term exposure to Indoor Radon is necessary to determine the effects of Indoor Radon exposure on health. However, measuring long-term exposure to Radon is labor intensive and costly. While developing models for estimating Indoor Radon concentrations are very difficult and unrealistic due to the many factors affecting Radon concentrations, several studies have attempted to estimate Indoor Radon concentrations with mathematical models based on mass balance equations. However, these models are only applicable to specific regions or situations, and some require actual measurement data. This study sought to develop a widely applicable model for estimating mean annual Indoor Radon concentrations in actual residences considering seasonal variations in Indoor Radon. The model is based on a mass balance equation using data on geographical factors, building characteristics, meteorological factors, and nationwide Radon surveys. The primary factor in our model is the infiltration factor, which can vary according to region, building materials, cracks, floor type, etc. In this study, infiltration factor was calculated according to the type of housing and groundwater usage, and the results thereof were applied to estimate Indoor Radon concentrations. Overall, measured concentrations and estimates of Indoor Radon concentrations using the infiltration factor were similar. This model showed better performance than our previous model, except for a few high concentration residences.
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Indoor Radon and lung cancer estimation of attributable risk disease burden and effects of mitigation
Yonsei Medical Journal, 2018Co-Authors: Si Heon Kim, Cheolmin Lee, Sang Baek Koh, Changsoo Kim, Dae Ryong KangAbstract:Purpose Exposure to Indoor Radon is associated with lung cancer. This study aimed to estimate the number of lung cancer deaths attributable to Indoor Radon exposure, its burden of disease, and the effects of Radon mitigation in Korea in 2010. Materials and methods Lung cancer deaths due to Indoor Radon exposure were estimated using exposure-response relations reported in previous studies. Years of life lost (YLLs) were calculated to quantify disease burden in relation to premature deaths. Mitigation effects were examined under scenarios in which all homes with Indoor Radon concentrations above a specified level were remediated below the level. Results The estimated number of lung cancer deaths attributable to Indoor Radon exposure ranged from 1946 to 3863, accounting for 12.5-24.7% of 15623 total lung cancer deaths in 2010. YLLs due to premature deaths were estimated at 43140-101855 years (90-212 years per 100000 population). If all homes with Radon levels above 148 Bq/m³ are effectively remediated, 502-732 lung cancer deaths and 10972-18479 YLLs could be prevented. Conclusion These findings suggest that Indoor Radon exposure contributes considerably to lung cancer, and that reducing Indoor Radon concentration would be helpful for decreasing the disease burden from lung cancer deaths.
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Estimation of Seasonal Correction Factors for Indoor Radon Concentrations in Korea
International journal of environmental research and public health, 2018Co-Authors: Ji Hyun Park, Cheolmin Lee, Hyun Young Lee, Dae Ryong KangAbstract:Long-term exposure to high Radon concentration exerts pathological effects and elicits changes in respiratory function, increasing an individual’s risk of developing lung cancer. In health risk assessment of Indoor Radon, consideration of long-term exposure thereto is necessary to identify a relationship between Indoor Radon exposure and lung cancer. However, measuring long-term Indoor Radon concentration can be difficult, and a statistical model for predicting mean annual Indoor Radon concentrations may be readily applicable. We investigated the predictability of mean annual Radon concentrations using national data on Indoor Radon concentrations throughout the spring, summer, fall, and winter seasons in Korea. Indoor Radon concentrations in Korea were highest in the winter and lowest in the summer. We derived seasonal correction and seasonal adjustment factors for each season based on the method proposed by previous study. However, these factors may not be readily applicable unless measured in a specific season. In this paper, we separate seasonal correction factors for each month of the year (new correction factors) based on correlations between Indoor Radon and meteorological factors according to housing type. To evaluate the correction factors, we assessed differences between estimated and measured mean annual Radon concentrations. Roughly 97% of the estimated values were within ±40 Bq/m3 of actual measured values in detached houses, and roughly 85–87% of the estimated values were within ±40 Bq/m3 of the measured values in other residences. In most cases, the seasonal correction factors and the new correction factors had slightly better agreement than the seasonal adjustment factor. For predicting mean annual Radon concentrations, the seasonal correction factors or seasonal adjustment factors can be of use when actual measurements of Indoor Radon concentrations for a specific season are available. Otherwise, the new correction factors may be more readily applicable.
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Measurement and modeling of Indoor Radon concentrations in residential buildings
Environmental health and toxicology, 2018Co-Authors: Ji Hyun Park, Cheolmin Lee, Hyun Young Lee, Sungim Whang, Dae Ryong KangAbstract:Radon, the primary constituent of natural radiation, is the second leading environmental cause of lung cancer after smoking. To confirm a relationship between Indoor Radon exposure and lung cancer, estimating cumulative levels of exposure to Indoor Radon for an individual or population is necessary. This study sought to develop a model for estimate Indoor Radon concentrations in Korea. Especially, our model and method may have wider application to other residences, not to specific site, and can be used in situations where actual measurements for input variables are lacking. In order to develop a model, Indoor Radon concentrations were measured at 196 ground floor residences using passive alpha-track detectors between January and April 2016. The arithmetic mean (AM) and geometric mean (GM) means of Indoor Radon concentrations were 117.86±72.03 and 95.13±2.02 Bq/m3, respectively. Questionnaires were administered to assess the characteristics of each residence, the environment around the measuring equipment, and lifestyles of the residents. Also, national data on Indoor Radon concentrations at 7643 detached houses for 2011-2014 were reviewed to determine Radon concentrations in the soil, and meteorological data on temperature and wind speed were utilized to approximate ventilation rates. The estimated ventilation rates and Radon exhalation rates from the soil varied from 0.18 to 0.98/hr (AM, 0.59±0.17/hr) and 326.33 to 1392.77 Bq/m2/hr (AM, 777.45±257.39; GM, 735.67±1.40 Bq/m2/hr), respectively. With these results, the developed model was applied to estimate Indoor Radon concentrations for 157 residences (80% of all 196 residences), which were randomly sampled. The results were in better agreement for Gyeonggi and Seoul than for other regions of Korea. Overall, the actual and estimated Radon concentrations were in better agreement, except for a few low-concentration residences.
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Indoor Radon exposure and lung cancer: a review of ecological studies
Annals of occupational and environmental medicine, 2016Co-Authors: Ji Young Yoon, Jung Dong Lee, So Won Joo, Dae Ryong KangAbstract:Lung cancer has high mortality and incidence rates. The leading causes of lung cancer are smoking and Radon exposure. Indeed, the World Health Organization (WHO) has categorized Radon as a carcinogenic substance causing lung cancer. Radon is a natural, radioactive substance; it is an inert gas that mainly exists in soil or rock. The gas decays into radioactive particles called Radon progeny that can enter the human body through breathing. Upon entering the body, these radioactive elements release α-rays that affect lung tissue, causing lung cancer upon long-term exposure thereto. Epidemiological studies first outlined a high correlation between the incidence rate of lung cancer and exposure to Radon progeny among miners in Europe. Thereafter, data and research on Radon exposure and lung cancer incidence in homes have continued to accumulate. Many international studies have reported increases in the risk ratio of lung cancer when Indoor Radon concentrations inside the home are high. Although research into Indoor Radon concentrations and lung cancer incidence is actively conducted throughout North America and Europe, similar research is lacking in Korea. Recently, however, studies have begun to accumulate and report important data on Indoor Radon concentrations across the nation. In this study, we aimed to review domestic and foreign research into Indoor Radon concentrations and to outline correlations between Indoor Radon concentrations in homes and lung cancer incidence, as reported in ecological studies thereof. Herein, we noted large differences in Radon concentrations between and within individual countries. For Korea, we observed tremendous differences in Indoor Radon concentrations according to region and year of study, even within the same region. In correlation analysis, lung cancer incidence was not found to be higher in areas with high Indoor Radon concentrations in Korea. Through our review, we identified a need to implement a greater variety of statistical analyses in research on Indoor Radon concentrations and lung cancer incidence. Also, we suggest that cohort research or patient-control group research into Radon exposure and lung cancer incidence that considers smoking and other factors is warranted.
Douglas G. Mose - One of the best experts on this subject based on the ideXlab platform.
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Geographic Information System Application to the Problem of Predicting Indoor Radon Concentrations
2010Co-Authors: Douglas G. Mose, George Siaway, Jim MetcalfAbstract:It would be extremely useful to determine if, on a county-size scale, there might be some predictability to Indoor Radon. One approach is to make an application of GIS and 3D visualization to explore the Radon problem in Fairfax County in northern Virginia, to evaluate correlations between Indoor Radon and geology, elevation, slope, and aeroradioactivity. It was found that there is a tendency for Indoor Radon to be greater in some parts of Fairfax County in homes on some geological units, in homes constructed on lower slopes, on sites at lower elevations, and in areas of higher aeroradioactivity. However, none of these physical variables exhibits a strong enough control on Indoor Radon to be used to construct Radon potential maps that carry a high confidence of accuracy.
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Summer Indoor Radon Exceeds Winter Indoor Radon
2010Co-Authors: Douglas G. Mose, George W. Mushrush, George SaiwayAbstract:It has been considered true for many years, probably because of commentary in US-EPA publications for the general public, that winter concentrations of Indoor Radon are greater than summer concentrations. The higher amount in the winter is attributed to the observation that people normally keep their windows closed during the winter, allowing Indoor Radon concentrations to rise. The lower Radon concentrations in the summer might occur because often open their windows, allowing low-Radon outside air to enter the home. It now appears that seasonal rainfall can cause unexpected Indoor Radon concentrations. In our study of over 1000 homes, where Indoor Radon was measured seasonally over an entire year, a summer season that had above normal rainfall had higher Indoor Radon than the prior winter, which had below normal precipitation.
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Correlation Test Between Indoor Radon and Surficial Gamma Radiation in Northern Virginia
Journal of environmental science and health. Part A Toxic hazardous substances & environmental engineering, 2006Co-Authors: George Saiway, George W. Mushrush, Douglas G. MoseAbstract:In northern Virginia, significant Indoor Radon differences occur due to soil chemistry, home heating system and precipitation. Homes constructed on soil over some geological units had Indoor Radon that exceeded the United States Environmental Protection Agency Maximum Concentration Level of 4 picoCuries/liter for home buyers. Seasons with more precipitation tend to have higher average Indoor Radon. Homes with electrical heating systems averaged almost 50% higher Indoor Radon than homes with gas or oil furnaces. Comparisons between Indoor Radon and soil Radon show a positive correlation, suggesting that soil aero radioactivity measurements can delineate areas with a high potential for Indoor Radon.
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Comparisons Between Soil Radon and Indoor Radon
Energy Sources, 1999Co-Authors: Douglas G. Mose, George W. MushrushAbstract:Several thousand Indoor Radon measurements have been obtained for homes in northern Virginia. Compilations of these data according to the geologic units under the homes show that some units have relatively high or relatively low median Indoor Radon levels, and that these differences persist through all four seasons. An attempt to determine if soil Radon and soil permeabilitycould yield similar results, in terms of relative Indoor Radon, was not successful. Care should be taken in using such measurements to characterize the potential for Radon problems in established communities and in areas of as-yet undeveloped property.
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Influence of local geology on the concentration of Indoor Radon in Maryland
Energy Sources, 1999Co-Authors: Douglas G. Mose, George W. MushrushAbstract:Approximately 58,000 Indoor Radon measurements are available for homes in Maryland. A comparative study between compilations of activated-charcoal and alpha-track measurements of Indoor Radon in zip-code-size geographic areas indi cated that both of these methods are useful and are equally able to estimate regional Indoor Radon. Indoor Radon measurements compiled according to zip code areas can be used to create state-size Radon hazard maps. In Maryland the area with the highest Indoor Radon (mostly composed of zip code areas that average over 8 pCi/L) is the western half of the Piedmont Province and the eastern side of the Coastal Plain Province. The eastern half of the Piedmont and the eastern half of the Valley and Ridge mostly have intermediate and high Indoor Radon levels (4-8 and > 8 pCi/L). The Blue Ridge, western side of the Valley and Ridge, and Plateau Province each has relatively few zip code areas, but the data suggest a range from low to high Indoor Radon levels. The western side of the Co...
George W. Mushrush - One of the best experts on this subject based on the ideXlab platform.
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Summer Indoor Radon Exceeds Winter Indoor Radon
2010Co-Authors: Douglas G. Mose, George W. Mushrush, George SaiwayAbstract:It has been considered true for many years, probably because of commentary in US-EPA publications for the general public, that winter concentrations of Indoor Radon are greater than summer concentrations. The higher amount in the winter is attributed to the observation that people normally keep their windows closed during the winter, allowing Indoor Radon concentrations to rise. The lower Radon concentrations in the summer might occur because often open their windows, allowing low-Radon outside air to enter the home. It now appears that seasonal rainfall can cause unexpected Indoor Radon concentrations. In our study of over 1000 homes, where Indoor Radon was measured seasonally over an entire year, a summer season that had above normal rainfall had higher Indoor Radon than the prior winter, which had below normal precipitation.
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Correlation Test Between Indoor Radon and Surficial Gamma Radiation in Northern Virginia
Journal of environmental science and health. Part A Toxic hazardous substances & environmental engineering, 2006Co-Authors: George Saiway, George W. Mushrush, Douglas G. MoseAbstract:In northern Virginia, significant Indoor Radon differences occur due to soil chemistry, home heating system and precipitation. Homes constructed on soil over some geological units had Indoor Radon that exceeded the United States Environmental Protection Agency Maximum Concentration Level of 4 picoCuries/liter for home buyers. Seasons with more precipitation tend to have higher average Indoor Radon. Homes with electrical heating systems averaged almost 50% higher Indoor Radon than homes with gas or oil furnaces. Comparisons between Indoor Radon and soil Radon show a positive correlation, suggesting that soil aero radioactivity measurements can delineate areas with a high potential for Indoor Radon.
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Comparisons Between Soil Radon and Indoor Radon
Energy Sources, 1999Co-Authors: Douglas G. Mose, George W. MushrushAbstract:Several thousand Indoor Radon measurements have been obtained for homes in northern Virginia. Compilations of these data according to the geologic units under the homes show that some units have relatively high or relatively low median Indoor Radon levels, and that these differences persist through all four seasons. An attempt to determine if soil Radon and soil permeabilitycould yield similar results, in terms of relative Indoor Radon, was not successful. Care should be taken in using such measurements to characterize the potential for Radon problems in established communities and in areas of as-yet undeveloped property.
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Influence of local geology on the concentration of Indoor Radon in Maryland
Energy Sources, 1999Co-Authors: Douglas G. Mose, George W. MushrushAbstract:Approximately 58,000 Indoor Radon measurements are available for homes in Maryland. A comparative study between compilations of activated-charcoal and alpha-track measurements of Indoor Radon in zip-code-size geographic areas indi cated that both of these methods are useful and are equally able to estimate regional Indoor Radon. Indoor Radon measurements compiled according to zip code areas can be used to create state-size Radon hazard maps. In Maryland the area with the highest Indoor Radon (mostly composed of zip code areas that average over 8 pCi/L) is the western half of the Piedmont Province and the eastern side of the Coastal Plain Province. The eastern half of the Piedmont and the eastern half of the Valley and Ridge mostly have intermediate and high Indoor Radon levels (4-8 and > 8 pCi/L). The Blue Ridge, western side of the Valley and Ridge, and Plateau Province each has relatively few zip code areas, but the data suggest a range from low to high Indoor Radon levels. The western side of the Co...
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Prediction of Indoor Radon based on soil Radon and soil permeability
Journal of Environmental Science and Health Part A, 1999Co-Authors: Douglas G. Mose, George W. MushrushAbstract:Evidence indicates that for homes within a geographically small area, Indoor Radon can be predicted using soil Radon and soil permeability. In northern Virginia, an area of temperate climate and rolling topography, soil measurements taken adjacent to and under 150 homes were compared to their Indoor Radon. Indoor Radon above 5 picoCuries/Liter (pCi/L) occurred in homes with soil Radon in excess of 2000 pCi/L, but it also occurred with soil Radon as low as 1000 pCi/L if the permeability exceeded 0.5 inches/hour.
Charles E. Chrosniak - One of the best experts on this subject based on the ideXlab platform.
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Soil Radon, permeability, and Indoor Radon prediction
Environmental Geology and Water Sciences, 1992Co-Authors: Douglas G. Mose, George W. Mushrush, Charles E. ChrosniakAbstract:Attempts to predict which geographic areas should be associated with a high percentage of homes with unusually high Indoor Radon levels have been based on estimates of soil Radon and soil permeability for geological units. In northern Virginia and southern Maryland, it appears that predictions of Indoor Radon based on estimates of homesite soil Radon and soil permeability are very useful.
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Seasonal Indoor Radon variations related to precipitation
Environmental and molecular mutagenesis, 1991Co-Authors: Douglas G. Mose, George W. Mushrush, Charles E. Chrosniak, W. F. MorganAbstract:Indoor Radon concentrations show a strong dependence on weather. Winter tends to be associated with higher than average Indoor Radon, and summer with lower than average. However, in northern Virginia, the summer of 1988 was wetter than the summer of 1987. Consequently, the regional Indoor Radon during the summer of 1988 was about 30% higher than during the summer of 1987, and Indoor Radon during the summer of 1988 actually exceeded the Indoor Radon level of the 1987-1988 winter. 40 refs.
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A 2‐year study of seasonal Indoor Radon variations in Northern Virginia
Journal of toxicology and environmental health, 1991Co-Authors: Douglas G. Mose, George W. Mushrush, Charles E. ChrosniakAbstract: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 approximately 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.
Ji Hyun Park - One of the best experts on this subject based on the ideXlab platform.
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A Deterministic Model for Estimating Indoor Radon Concentrations in South Korea.
International journal of environmental research and public health, 2019Co-Authors: Ji Hyun Park, Cheolmin Lee, Dae Ryong KangAbstract:Estimating long-term exposure to Indoor Radon is necessary to determine the effects of Indoor Radon exposure on health. However, measuring long-term exposure to Radon is labor intensive and costly. While developing models for estimating Indoor Radon concentrations are very difficult and unrealistic due to the many factors affecting Radon concentrations, several studies have attempted to estimate Indoor Radon concentrations with mathematical models based on mass balance equations. However, these models are only applicable to specific regions or situations, and some require actual measurement data. This study sought to develop a widely applicable model for estimating mean annual Indoor Radon concentrations in actual residences considering seasonal variations in Indoor Radon. The model is based on a mass balance equation using data on geographical factors, building characteristics, meteorological factors, and nationwide Radon surveys. The primary factor in our model is the infiltration factor, which can vary according to region, building materials, cracks, floor type, etc. In this study, infiltration factor was calculated according to the type of housing and groundwater usage, and the results thereof were applied to estimate Indoor Radon concentrations. Overall, measured concentrations and estimates of Indoor Radon concentrations using the infiltration factor were similar. This model showed better performance than our previous model, except for a few high concentration residences.
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Estimation of Seasonal Correction Factors for Indoor Radon Concentrations in Korea
International journal of environmental research and public health, 2018Co-Authors: Ji Hyun Park, Cheolmin Lee, Hyun Young Lee, Dae Ryong KangAbstract:Long-term exposure to high Radon concentration exerts pathological effects and elicits changes in respiratory function, increasing an individual’s risk of developing lung cancer. In health risk assessment of Indoor Radon, consideration of long-term exposure thereto is necessary to identify a relationship between Indoor Radon exposure and lung cancer. However, measuring long-term Indoor Radon concentration can be difficult, and a statistical model for predicting mean annual Indoor Radon concentrations may be readily applicable. We investigated the predictability of mean annual Radon concentrations using national data on Indoor Radon concentrations throughout the spring, summer, fall, and winter seasons in Korea. Indoor Radon concentrations in Korea were highest in the winter and lowest in the summer. We derived seasonal correction and seasonal adjustment factors for each season based on the method proposed by previous study. However, these factors may not be readily applicable unless measured in a specific season. In this paper, we separate seasonal correction factors for each month of the year (new correction factors) based on correlations between Indoor Radon and meteorological factors according to housing type. To evaluate the correction factors, we assessed differences between estimated and measured mean annual Radon concentrations. Roughly 97% of the estimated values were within ±40 Bq/m3 of actual measured values in detached houses, and roughly 85–87% of the estimated values were within ±40 Bq/m3 of the measured values in other residences. In most cases, the seasonal correction factors and the new correction factors had slightly better agreement than the seasonal adjustment factor. For predicting mean annual Radon concentrations, the seasonal correction factors or seasonal adjustment factors can be of use when actual measurements of Indoor Radon concentrations for a specific season are available. Otherwise, the new correction factors may be more readily applicable.
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Measurement and modeling of Indoor Radon concentrations in residential buildings
Environmental health and toxicology, 2018Co-Authors: Ji Hyun Park, Cheolmin Lee, Hyun Young Lee, Sungim Whang, Dae Ryong KangAbstract:Radon, the primary constituent of natural radiation, is the second leading environmental cause of lung cancer after smoking. To confirm a relationship between Indoor Radon exposure and lung cancer, estimating cumulative levels of exposure to Indoor Radon for an individual or population is necessary. This study sought to develop a model for estimate Indoor Radon concentrations in Korea. Especially, our model and method may have wider application to other residences, not to specific site, and can be used in situations where actual measurements for input variables are lacking. In order to develop a model, Indoor Radon concentrations were measured at 196 ground floor residences using passive alpha-track detectors between January and April 2016. The arithmetic mean (AM) and geometric mean (GM) means of Indoor Radon concentrations were 117.86±72.03 and 95.13±2.02 Bq/m3, respectively. Questionnaires were administered to assess the characteristics of each residence, the environment around the measuring equipment, and lifestyles of the residents. Also, national data on Indoor Radon concentrations at 7643 detached houses for 2011-2014 were reviewed to determine Radon concentrations in the soil, and meteorological data on temperature and wind speed were utilized to approximate ventilation rates. The estimated ventilation rates and Radon exhalation rates from the soil varied from 0.18 to 0.98/hr (AM, 0.59±0.17/hr) and 326.33 to 1392.77 Bq/m2/hr (AM, 777.45±257.39; GM, 735.67±1.40 Bq/m2/hr), respectively. With these results, the developed model was applied to estimate Indoor Radon concentrations for 157 residences (80% of all 196 residences), which were randomly sampled. The results were in better agreement for Gyeonggi and Seoul than for other regions of Korea. Overall, the actual and estimated Radon concentrations were in better agreement, except for a few low-concentration residences.
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A review on mathematical models for estimating Indoor Radon concentrations
Annals of occupational and environmental medicine, 2016Co-Authors: Ji Hyun Park, Dae Ryong KangAbstract:Radiation from natural sources is one of causes of the environmental diseases. Radon is the leading environmental cause of lung cancer next to smoking. To investigate the relationship between Indoor Radon concentrations and lung cancer, researchers must be able to estimate an individual’s cumulative level of Indoor Radon exposure and to do so, one must first be able to assess Indoor Radon concentrations. In this article, we outline factors affecting Indoor Radon concentrations and review related mathematical models based on the mass balance equation and the differential equations. Furthermore, we suggest the necessities of applying time-dependent functions for Indoor Radon concentrations and developing stochastic models.