• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.67-68
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• 2003

라돈은 일반적으로 가장 잘 알려진 천연 방사성핵종 중 하나로서 무향 무색의 불활성기체이며 붕괴과정에서 알파입자를 방출한다. 라돈에 의한 피폭선량은 라돈붕괴에 의해 생성된 라돈자손이 호흡기관 표면에 침착되어 방출하는 알파선에 기인한다. 따라서, 피폭선량에 주로 기인하는 것은 라돈 자신이 아니라 그의 단 반감기 라돈자손들이다. 이처럼 라돈은 잘 알려진 폐암 유발원으로서 고농도의 라돈에 장기간 노출되는 경우 폐암을 유발할 수 있다. UNSCEAR 보고서(1993)는 자연 환경중에서 인간이 받는 연간 총 피폭선량인 2.4 mSv중 약 50%에 해당하는 1.15 mSv가 라돈과 그 자손에 의한 것이며 대부분 옥내에서의 호흡에 의해 비롯된다고 평가하고 있다. (중략)

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.17-25
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• 2016

In this study, the air quality of underground and overground railway stations was evaluated focusing on the degree of influence of the outside air quality. The measured components were particulate matter ($PM_{10}$), carbon dioxide ($CO_2$), carbon monoxide (CO), nitrogen dioxide ($NO_2$), formaldehyde (HCHO), ozone ($O_3$), total airborne bacteria (TAB), total volatile organic carbon (TVOC), and Radon (Rn), which are included in the maintenance standards and recommended standards of the Indoor Air Quality Management Act. Also, the indoor/outdoor concentration ratios of $PM_{10}$, $NO_2$, and $O_3$ were calculated to estimate the influence of the outdoor air quality. The concentrations of $PM_{10}$ HCHO, TVOC, $NO_2$, and Rn in the underground stations were found to be higher than those in the overground stations. These results indicate that the (present) generation of contaminants are caused by the indoor source of the underground station. The ozone concentration of the overground stations was higher than that of the underground stations, which indicates that the outdoor ozone concentration influenced that of the overground stations directly. Thus, methods of improving the IAQ should take into consideration the types of contamination.

• Journal of Preventive Medicine and Public Health
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• v.36 no.3
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• pp.230-238
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• 2003

Objectives : To estimate the value of statistical life (VSL) and health damage cost on theoretical mortality estimates due to environmental pollution. Methods : We assessed the health risk on three environmental problems and eight sub-problems. Willingness to pay (WTP) was elucidated from a questionnaire survey with dichotomous contingent valuation method and VSL (which is the division of WTP by the change of risk reduction) calculated from WTP. Damage costs were estimated by multiplying VSL by the theoretical mortality estimates. Results : VSLs from death caused by air pollution, indoor air pollution and drinking water contamination were about 0.3, 0.5 and 0.3 billion won, respectively. Damage costs of particulate matters ($PM_{10}$) and radon were higher in the sub-problems and were above 100 billion won. Because damage cost depends on theoretical mortality estimate and WTP, its uncertainty is reduced in the estimating process. Conclusion : Health damage cost or risk benefit should be considered as one scientific criterion for decision making in environmental policy.

• Journal of the Korean Wood Science and Technology
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• v.48 no.1
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• pp.86-94
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• 2020

This study serves as basic research for the development of a new wood-based building finishing material that improved the weakness of inorganic materials such as gypsum board and magnesium board widely used as interior finishing materials and brought out the strength of the wood. The results of evaluating the physical and mechanical properties and the environmental effect related to hazardous substance discharge having manufactured a wood-magnesium laminated composite are as follows. The thermal conductivity and thermal resistance of WML board was improved by about 28~109 percent over magnesium board due to the low thermal conductivity of wood. The adhesive strength of WML board showed a similar result to that of plywood as it exceeds 0.7N/㎟, the adhesive standard of wood veneer which is presented by KS F 3101. Bending strength and screw holding strength were more improved by manufacturing WML board than magnesium board. The WML board manufactured in this study satisfied the criteria for emissions of hazardous substances prescribed in the Indoor Air Quality Control Act, and confirmed the possibility of development as a new wood-based composite material that can replace existing inorganic materials.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.11
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• pp.1001-1010
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• 2010

The purpose of this study is to investigate the concentration levels of particle materials ($PM_{10}$, asbestos), gas materials ($CO_2$, CO, $NO_2$, HCHO, Rn, VOCs) and total suspended colony (TSC), and the correlations among these materials in indoor air quality of 54 multiple-use facilities and 15 public-use facilities of Gwangju. The highest mean concentration of $PM_{10}$ was $69.2\;{\mu}g/m^3$ at indoor parking place, followed by childcare facilities, large commercial building and subway station building. The highest mean concentration of CO was 2.7 ppm at indoor parking place and that of $CO_2$ was 604.1 ppm at medical service facilities. The highest mean concentration of $NO_2$ was 0.036 ppm at indoor parking place. The geomean concentration of HCHO was $3.6\;{\mu}g/m^3$ in all facilities and the highest was $631.8\;{\mu}g/m^3$ at art gallery. The geomean concentration of VOCs (5 species) was $24.14\;{\mu}g/m^3$ in all facilities and toluene was the highest material of $15.30\;{\mu}g/m^3$, followed by xylene, ethylbenzene, benzene and styrene. The highest mean concentration of TSC was $625.3\;CFU/m^3$ at jjimjilbang, followed by childcare facilities, medical service facilities and large commercial building. The highest of asbestos was 0.0072 each/cc at childcare facilities and that of radon was 1.41 pCi/L at art gallery. PM10 showed positive correlations to TSC with $R^2\0.5332$ by lognormal equation at childcare facilities. CO2 showed positive correlations to CO at childcare facilities and indoor parking place. Lognormal equation fitted to the VOCs data more than normal equation in all facilities.

• Journal of Radiation Protection and Research
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• v.31 no.2
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• pp.69-89
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• 2006

Biological mechanisms for ionizing radiation effects are different at low doses than at high doses. Radiation hormesis involves low-dose-induced protection and high-dose-induced harm. The protective component is associated with a reduction in the incidence of cancer below the spontaneous frequency, brought about by activation of defensive and repair processes. The Linear No-Threshold (LNT) hypothesis advocated by the International Commission on Radiological Protection (ICRP) and the Biological Effects of ionizing Radiation (BEIR) Report VII for cancer risk estimations Ignores hormesis and the presence of a threshold. Cancer incidences significantly less than expected have been found in a large number of epidemiological studies including, airline flight personnel, inhabitants of high radiation backgrounds, shipyard workers, nuclear site workers in scores of locations throughout the world, nuclear power utility workers, plutonium workers, military nuclear test site Participants, Japanese A-bomb survivors, residents contaminated by major nuclear accidents, residents of Taiwan living in $^{60}Co$ contaminated buildings, fluoroscopy and mammography patients, radium dial painters, and those exposed to indoor radon. Significantly increased cancer was not found at doses <200 $mSv^*$. Evidence for radiation hormesis was seen in both sexes for acute or chronic exposures, low or high LET radiations, external whole- or partial body exposures, and for internal radionuclides. The ubiquitous nature of the Healthy Worker Effect (HWE)-like responses in cellular, animal and epidemiological studies negates the HWE as an explanation for radiation hormesis. The LNT hypothesis is wrong and does not represent the true nature of the dose-response relationship, since low doses or dose-rates commonly result in thresholds and reduce cancer incidences below the spontaneous rate. Radiation protection organizations should seriously consider the cost and health implications of radiation hormesis.

• Radiation Oncology Journal
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• v.23 no.4
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• pp.243-252
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• 2005

Purpose: Indoor air quality (IAQ) in the radiation treatment center which is generally located underground is important to the health of hospital workers and patients treated over a long period of time. this study was conducted to measure and analyze the factors related to IAQ and subjective symptoms of sick building syndrome, and to establish the causes influencing IAQ and find a solution to the problems. Methods and Materials : Self administrated questionnaire was conducted to check the workers' symptoms and understanding of the work environment. Based on a preliminary investigation, the factors related to IAQ such as temperature, humidity, fine particulate. carbon dioxide, carbon monoxide, formaldehyde, total volatile organic compounds (TVOC), and radon gas were selected and measured for a certain period of time in specific sites where hospital workers stay long in a day. And we also evaluated the surrounding environment and the efficiency of the ventilating system simultaneously, and measured the same factors at the first floor (outdoor) to compare with outdoor all quality, All collected data were assessed by the recommended standard for IAQ of the domestic and international environmental organizations. Results: Hospital workers were discontented with foul odors, humidity and particulate. They complained symptoms related to musculo-skeletal system, neurologic system, and mucosal-irritatation. Most of the factors were not greater than the recommended standard, but the level of TVOC was third or fourth times as much as the measuring level of some offices in the United States. The frequency and the amount of the ventilating system were adequate, however, the problem arising in the position of outdoor-air inlets and indoor-air outlets involved a risk of the indraft of contaminated air. A careful attention was a requirement in handling and keeping chemical substances including a developing solution which has a risk of TVOC emissions, and repositioning the ventilating system was needed to solve the contaminated-air circulation immediately Conclusion We verified that some IAQ-related factors and inadequate ventilating system could cause subjective symptoms in hospital workers. The evaluation of IAQ was surely needed to improve the underground working environments for hospital workers and patients. On the basis of these data, from now on, we should actively engage in designs of the department of radiation oncology or improvement in environments of the existing facilities.