• Journal of Radiation Protection and Research
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• v.16 no.2
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• pp.41-54
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• 1991

This paper aimed to analyse dose sensitivity to the controllable parameters of indoor radon $(^{222}Rn)$ and its decay products (Rn-D) by applying the input~output linear system theory. Physical behaviors of $^{222}Rn\;&\;Rn-D$ were analyzed in terms of $(^{222}Rn)$ gas -generation, -migation and -infiltration to indoor environments, and the performance output-function, i. e. mean dose equivalent to Tracho-Bronchial (TB) lung region, was assessed to the following extented ranges of the controllable paramenters; a) the ventilation rate $constant({\lambda}_v)\;:\;0{\sim}50[h^{-l}].\;b)$ the attachment rate $constant({\lambda}_a)\;:\;0{\sim}500[h^{-l}].\;c)$ the unattached-deposition rate constant (${\lambda}^u_d)\;:\;0-50[h-l]$. A linear input-output model was reconstructed from the original models in literatures, as follows, which was modified into the matrices consisting of 111 nodal equations; a) indoor $^{222}Rn\;&\;Rn-D$ Behaviour; Jacobi-Porstendoerfer-Bruno model.

• Journal of the Korea Institute of Building Construction
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• v.17 no.1
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• pp.15-21
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• 2017

WHO reported that millions of people die every year because of diseases induced from environmental pollution. In 2012, approximately 7 million people were killed due to air pollution. Major cause of such pollution includes toxin, chemical waste, radiation and air pollution. Therefore, the significance and interest to indoor air quality has been continuously increased. Especially, the interest in radon, the ARC group 1 carcinogen, is rapidly increasing, and banning the use of construction materials that release radon, repairing aged buildings, and developing ventilators. To reduce the level of radon gas was inflowed to indoors and outdoors, this study is to research and develop a radon gas absorption board using absorbents. The absorbents utilized to absorb the radon gas were porous diatomite, natural zeolite, 4A zeolite and 13X zeolite and employed bentonite and illite, montmorillonites with the property of exchanging anions. As the main binder, magnesium oxide was used, with a content of 25% magnesium chloride.

• Analytical Science and Technology
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• v.28 no.5
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• pp.353-360
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• 2015

Boiling is an efficient removal method to reduce radon in groundwater when ventilating indoor air. 13 groundwater samples with various radon concentrations were used to evaluate the reduction rate of radon with heating temperature and time. The groundwater samples were obtained by Bladder pump and on-situ measurements such as dissolved oxygen (DO) and hydrogen concentration (pH) and so on were carried out by a flow cell system isolated from the ambient atmosphere environment. All samples for measuring radon in groundwater were analyzed by liquid scintillation counter (LSC). The experiment result showed that increasing groundwater temperature enhanced radon removal rate but the initial radon concentration with high level lowered the removal rate. This means that radon reduction in groundwater by heating needs more heating energy and longer heating time with radon concentrations. Radon removal rate in groundwater, therefore, mainly depends on the initial radon concentration, heating temperature, and heating time.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.11a
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• pp.47-51
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• 2006

Modern residing equipment developed much quantitatively along with economic growth but improvement for agreeable residing space of indoor environment is insufficient situation yet. Also, the latest sick-building syndrome discharging room contaminant such as Formaldehyde, toluene, radon etc. built house or buildings newly human body threaten. Radon of them is real condition that raise origination of lung cancer next to smoke. So, wish to in this research by one of solution way of these problems adsorption performance and specie performance excellent activated carbon to concrete bricks for deconstipating suppository that is room finish fare mix and examine closely after grasp physical, mechanical special quality, hazardous substance and specie performance effect. According to result that estimate environment efficiency evaluation, the $CO_2$ absorption amount displayed decrease effect more than about 90% in activated carbon metathesis rate 40% and radon release amount displayed tendency that decrease about $76{\sim}96%$ in activated carbon metathesis rate 40%.

• Journal of the Korea Institute of Building Construction
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• v.6 no.2 s.20
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• pp.105-109
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• 2006

Modern residing equipment developed much quantitatively along with economic growth but improvement for agreeable residing space of indoor environment is insufficient situation yet. Also, the latest sick-building syndrome discharging room contaminant such as Formaldehyde, toluene, radon etc. built house or buildings newly human body threaten. Radon of them is real condition that raise origination of lung cancer next to smoke. So, wish to in this research by one of solution way of these problems adsorption performance and specie performance excellent activated carbon to mortar for deconstipating suppository that is room finish fare mix and examine closely after grasp physical, mechanical special quality, hazardous substance and specie performance effect. According to result that estimate friendly-environment performance, the $CO_2$ absorption amount displayed decrease effect more than about 90% in activated carbon metathesis rate 80% and radon release amount displayed tendency that decrease about $75{\sim}85%$ in activated carbon metathesis rate 80%.

• Journal of Radiation Protection and Research
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• v.33 no.4
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• pp.173-181
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• 2008

To ensure the performance of radon detectors, three passive radon detectors ($RadTrak^{(R)}$, $Radopot^{(R)}$, and $E-PERM^{(R)}$)have been reviewed. The difference ratios of RadTrak and Radopot tested in the radon standard chamber were -13.2% and -6.0%, respectively, which were in good accordance within 20% of the value measured by $AlphaGUARD^{(R)}$. To ensure the performance of the long term measurement, the 3 detectors were installed at the same position of approximately one hundred of dwellings for one year. The correlation curve between RadTrak and Radopot shows good agreement with a correlation coefficient ($R^2$) of 0.91. However, The correlation curve between E-PERM and Radopot shows bad agreement ($R^2$ = 0.021). In addition, the distribution map of annual mean indoor gamma dose rate measured with E-PERM was not in accordance with the distribution map of outdoor gamma dose rate measured by Portable Ion Chamber. According to the results, some requisites for the selection of the radon passive detectors in the large-scale indoor radon survey were discussed.

• Journal of Environmental Health Sciences
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• v.43 no.5
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• pp.382-392
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• 2017

Objectives: The purpose of this study is to obtain basic data on the development of a risk communication model through an investigation of risk perception for radon and identify effective risk communication channels. Methods: A questionnaire was used to evaluate differences in perception level according to respective communication channels. A chi-squared test was used to analyze the difference in pre- and post-risk communication by communication channel. One-way ANOVA was used to analyze the difference in the radon risk perception rate for each communication channel. Results: All of the communication channels resulted in increased radon risk perception, but there was no statistical difference between them in terms of perception (p>0.05). However, based on previous findings that it is effective to use a multi-channel approach, it is considered that communication channels based on duplicate avenues is most appropriate. Conclusions: It is expected that this study will be used as basic data to better understand the formation of public opinion about radon risk and to understand the social reaction to each risk factor.

• Journal of Cancer Prevention
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• v.22 no.4
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• pp.234-240
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• 2017

Background: Lung cancer is the leading cause of cancer-related death worldwide, for which smoking is considered as the primary risk factor. The present study was conducted to determine whether genetic alterations induced by radon exposure are associated with the susceptible risk of lung cancer in never smokers. Methods: To accurately identify mutations within individual tumors, next generation sequencing was conduct for 19 pairs of lung cancer tissue. The associations of germline and somatic variations with radon exposure were visualized using OncoPrint and heatmap graphs. Bioinformatic analysis was performed using various tools. Results: Alterations in several genes were implicated in lung cancer resulting from exposure to radon indoors, namely those in epidermal growth factor receptor (EGFR), tumor protein p53 (TP53), NK2 homeobox 1 (NKX2.1), phosphatase and tensin homolog (PTEN), chromodomain helicase DNA binding protein 7 (CHD7), discoidin domain receptor tyrosine kinase 2 (DDR2), lysine methyltransferase 2C (MLL3), chromodomain helicase DNA binding protein 5 (CHD5), FAT atypical cadherin 1 (FAT1), and dual specificity phosphatase 27 (putative) (DUSP27). Conclusions: While these genes might regulate the carcinogenic pathways of radioactivity, further analysis is needed to determine whether the genes are indeed completely responsible for causing lung cancer in never smokers exposed to residential radon.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.33 no.2
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• pp.115-125
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• 2023

Objectives: This study was conducted to measure the level of radon in the air at a highway tunnel construction site in a gneiss area using the New Austrian Tunneling Method (NATM) and to evaluate exposure levels by occupation. Methods: Radon concentrations in the air were measured using E-PERM at points 300 m, 600 m, and 900 m from the tunnel entrance during the excavation and waterproofing work inside the tunnel. In addition, radon concentrations were measured during external excavation to compare with the inside of the tunnel. Personal exposure levels for major occupations including tunnel workers, construction equipment operators, waterproofers, shotcrete workers, and safety and health managers who participated in the construction were estimated using radon concentration measured in the work process area and working hours by occupation. Results: As a result of a total of 77 radon measurements, the geometric mean (GM) concentration was 71.1 Bq/m³, and the maximum concentration was 127.3 Bq/m³, which was below the indoor air quality criteria. Radon concentration by process decreased in the order of the tunnel excavation process (GM= Bq/m³, GSD=1.2), waterproofing process (GM=73.35 Bq/m³, GSD=1.2), and outside excavating process (GM=45.28 Bq/m³, GSD=1.2). Processes inside the tunnel were significantly higher than outside excavating processes (p<0.05). There was no statistically significant difference in radon concentration measured inside by distance from the tunnel entrance, but the innermost point of the tunnel, 900 m (GM=79.24 Bq/m³, GSD=1.27), measured the highest. Conclusions: The occupation with the highest individual exposure to radon was tunnel worker (64.16 Bq/m³), followed by construction equipment driver (64.04 Bq/m³) and waterproofer (63.13 Bq/m³).

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2008.10a
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• pp.513-515
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• 2008