• 한국태양에너지학회:학술대회논문집
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• 2009.04a
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• pp.97-101
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• 2009

Calculating and predicting the thermal comfort in outdoor environment are difficult than in indoor environment because composition parameters are variable, interrelations among parameters are very complex and human activities in outdoor are diverse. Moreover, the thermal expectancy of subject in outdoor environment is different from that of indoor environment. The aims of this study are to examine the difference between indoor and outdoor thermal comfort range. With this in mind, field measurement for estimating outdoor thermal environment and a questionnaire survey with simultaneous measurement around the subject were conducted.

• Journal of Korean Society for Atmospheric Environment
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• v.3 no.2
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• pp.33-38
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• 1987

A pilot study on indoor air concentrations of nitrogen dioxide $(NO_2)$ was undertaken in the Seoul area, Korea dudring February-April 1986. Indoor and outdoor data on nitrogen dioxide concentrations were obtained for 48 private residences. Personal exposure to $NO_2$ was also investigated. Indoor outdoor ratio of $NO_2$ concentrations was 0.87, while the correlations between the indoor and outdoor levels were less than 0.50 for $NO_2$. Homes with an unvented space heater had average living room $NO_2$ concentrations approximately double those with a vented space heater. Residences with smokers have significantly higher living room $NO_2$ levels than those without smokers.

• Journal of Environmental Health Sciences
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• v.36 no.5
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• pp.351-359
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• 2010

The objectives of this study were to understand the characteristics of residents in industrial areas and factors affecting exposure to the Volatile Organic Compounds(VOCs : Benzene, Toluene, Xylene) as well as to assess exposure levels according to house-type, and whether residents were indoors or outdoors. This research was designed to assess the differences in exposure levels to indoor, outdoor and personal VOCs in a case group and a control group across all areas, as well as in each different area, from May to October 2007, in. 110 residents of the G, Y and H industrial areas of the Jun-nam province. The geometric mea-levels of airborne benzene for the case group 1.31part per billion(ppb) indoor, 1.29 ppb outdoor, and 1.32 ppb for personal exposure were significantly higher than for the control group 0.99, 0.87 and 0.57 ppb, respectively. The geometric mean level for toluene personal exposure across the G, Y and H areas was 5.70 ppb for the case group and 6.31 ppb for the control group. While the outdoor level was 4.27 ppb for the case group and 5.06 ppb for the control group, The indoor level for the case group was 4.78 ppb, similar to that of the control group 4.69 ppb. The geometric mean levels for airborne xylene across the G, Y and H areas were 0.16 ppb(outdoor), 0.12 ppb(personal exposure) and 0.10 ppb(indoor) for the case group, and for the control group were 0.17(personal exposure) and 0.09 ppb(indoor and outdoor). The indoor/outdoor(I/O) ratio for case group is 1.19, while that of the control group is 1.15, indicating that the indoor level was higher than the outdoor level. The interrelationship differences among the three different types of levels in the air in the G, Y and H areas are statistically significant, except for the difference between the indoor and outdoor figures for xylene. In terms of the different types of houses and energy type uesd, the geometric mean level for airborne benzene, toluene and xylene for houses were 1.61, 5.39 and 0.12 ppb, respectively. while the figures for flats were 0.67, 3.32 and 0.05 ppb, respectively. Outdoors, the levels of benzene and toluene in flats were 0.71 and 2.62 ppb, respectively. and 1.58 and 5.35 ppb in houses. For personal exposure, the house levels of benzene, toluene and xylene were all higher than for flats. Houses using oil for heating have significantly higher levels than flats, which use gas for heating.

• Korean Journal of Remote Sensing
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• v.36 no.6_3
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• pp.1721-1732
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• 2020

Elementary school students spend a lot of time in a school and are more exposed to indoor air pollution. Also the students are physically growing and have a relatively high respiratory rate per unit weight compared to adults, so it is known that there is a high sensitivity to indoor air pollution. Therefore, indoor air quality in a school is becoming an important factor for the student's health. In this study, a correlation analysis using levels of indoor and outdoor Particulate Matter (PM) measured from five elementary schools in Seoul was performed to evaluate the effect of outdoor PM on indoor PM. PM ratio and indoor/outdoor (I/O) ratio were also analyzed to investigate the actual condition of indoor air quality and effect of outdoor PM on indoor PM. As a result, the correlation between indoor and outdoor PM in elementary school was more significant in PM2.5 and PM1 than PM10. In the case of I/O ratio, the I/O ratio of PM10 was higher than that of 1 in four elementary schools except SD (BB:2.21, NS: 1.67, IS: 1.73, SI: 1.17). This indicates that the activity of students has a great effect on the concentration of indoor PM10.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.06a
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• pp.293-298
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• 2005

Indoor air quality can be affected by indoor sources, ventilation, decay and outdoor levels. Although technologies exist to measure these factors, direct measurements are often difficult. The purpose of this study was to develop an alternative method to characterize indoor environmental factors by multiple indoor and outdoor measurements. Indoor and outdoor NO$_2$ and VOCs(benzene, toluene, xylene) concentrations were measured every 3 days for 60 consecutive days in 30 houses in Seoul, Asan and Daegu, Korea. Using a mass balance model and regression analysis, penetration factor (ventilation rate divided by the sum of ventilation rate and deposition constant) and source strength factor (source strength divided by the sum of ventilation rate and deposition constant) were calculated using multiple indoor and outdoor measurements. Subsequently, NO$_2$ and VOCs source strengths (ppb/hr) and deposition constant (K, hr$^{-1}$) were estimated. Deposition constants of NO$_2$, toluene and xylene were 0.98 ${\pm}$ 0.28, 0.71 ${\pm}$ 0.24 and 0.74 ${\pm}$ 0.53 hr$^{-1}$, respectively. Source strengths of NO$_2$, toluene and xylene were 16.28 ${\pm}$ 7.47,31.25 ${\pm}$ 38.45 and 23.45 ${\pm}$ 19.67 ppb/hr, respectively In conclusion, indoor environmental factors were effectively characterized by this method using multiple indoor and outdoor measurements.

• Journal of the Korean Society of Safety
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• v.33 no.5
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• pp.51-59
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• 2018

It is difficult to determine the outdoor toxic level of hazardous chemicals that are leaked in the building, since there are no efficient ways to calculate how much percentage of the leaked chemicals is released into the outdoor atmosphere. In address to these problems, we propose a reasonable box model that can quantitatively evaluate the mass rate of the indoor chlorine leakage into the outside of the building. The proposed method assumes that the indoor chlorine leakage is fully mixed with the indoor air, and then the mixture of the chlorine and indoor air is exfiltrated into the outside of the building through effective leakage areas of the building. It is found that the exfiltration rate of the mixture of the chlorine and indoor air is strongly dependent on the temperature difference between inside and outside the building than the atmospheric wind speed. As compared with a conventional method that uses a vague mitigation factor, our method is more effective to evaluate the outdoor toxic threat zone of the chlorine that are leaked in the building, because it can consider the degree of airtight of the building in the evaluation of the threat zone.

• Journal of environmental and Sanitary engineering
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• v.19 no.4 s.54
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• pp.61-68
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• 2004

Hair driers and chemicals used in beauty shops generate a number of heavy metals and $PM_{10}$. Also many $PM_{10}$ are produced during hair cut. The pollutions raised health problems and uncomfortableness to hair dressers and customers in beauty shops. This study investigated to assess indoor, outdoor and personal particulate pollutants ($PM_{10}$ and Heavy metals) mean concentrations and the source of the pollutants in beauty shops. The results are summarized as follows: 1. The measured mean concentrations of respiratory particulates were $30.5ng/m^2$ in indoor, $30.5ng/m^2$ in outdoor and$44.0ng/m^2$ on personal levels. The personal concentration was found higher than indoor and outdoor concentrations. 2. The heavy metals mean concentrations were showed as indoor (Na>Zn>Cr), outdoor (Cr>Zn>Pb), and personal (Na>Cr>Zn) levels. 3. Chemicals and hair driers were regarded as the major sources of the pollutions. 4. Na was correlated with Mg, Zn and Cd, while Mg was correlated with Ni. Mn was correlated with Cu, Zn and AS, where as Cu was correlated with Zn, As and Cd. Zn and As, and Asand Cd were correlated each other. Na was inversely correlated with Cr.

• Journal of Environmental Health Sciences
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• v.34 no.2
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• pp.137-147
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• 2008

This study evaluated the effects of the human activity and outdoor air on concentrations of size-selective particulate matters (PM) by conducting a realtime measurement in classrooms and on roofs at 4 elementary schools, 3 middle schools and 3 high schools in Incheon City. PM concentrations featured repetitive pattern of increasing during break time (including lunch hours) and cleaning time while decreasing during class hours. This trend was more prominent with inhalable PM and PM10 than fine PMs (PM2.5, PM1.0). The indoor/outdoor (I/O) ratio of inhalable PM and PM10 exceeded 1 while that of fine PMs was close to or below 1. The PM2.5 (out)/PM10 (out) ratio stood at 0.59 (${\pm}0.16$) and the PM2.5 (in)/PM10 (in) ratio was 0.29 (${\pm}0.09$), suggesting that occupant activity had a greater effect upon coarse particles (PM10-PM2.5) than upon fine particles (PM2.5, PM1.0). The correlations between the indoor and the outdoor PM concentrations showed a stronger positive correlation for fine particles than that of coarse particles. The linear regression analysis of PM concentrations indoor and outdoor indicated a higher determinant coefficient ($r^2>0.9$), and consistency for fine particles than in case of coarse particles. In conclusion, the results of this study suggest that the indoor coarse particle concentration is more attributed to occupant activity and the indoor fine particle concentration is more influenced by outdoor air pollution.

• Journal of the Korean Institute of Rural Architecture
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• v.20 no.4
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• pp.39-51
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• 2018

In order to improve the housing environment and quality of life for the rural elderly, this study aims to identify and present the status of community centers, most widely used by the elderly in rural areas. Through the literature review, type and space elements of community centers were derived and selected three target areas were investigated. As a result of literature analysis, the space type of rural community centers were classified as indoor space and outdoor space. The indoor space types were classified as entry space, public space, sanitary space and the outdoor space were classified as entry space and leisure space. Some community centers were surveyed in Seocheon-gun, Wanju-gun, and Cheongju-city. Results indicate the indoor and outdoor space design and elements were undergoing a lot of inconvenience partly because standard design was considered and the space was not planned for the physical, psychological and social health of the rural elderly. Therefore, this study will be used as a basis for building healthier and more friendly residential environments that can enhance the health and quality of life for the elderly in rural areas.

• Journal of Environmental Science International
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• v.15 no.2
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• pp.101-106
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• 2006

The work of hairdressers includes washing, coloring, bleaching, permanent waving, conditioning, and cutting hair. Hairdressers are subjected to a number of physical and toxicological hazards. The toxicological hazards are those resulting from exposure to a wide range of chemicals that are usually classified active processes. In this study, twenty beauty shops were selected to assess the exposure to indoor air pollutants such as VOCs and particulate matter $(PM_{10})$ during one month from September 1 to September 30, 2003. Indoor air quality of beauty shops might be worse by vehicle emissions because the beauty shops were generally located near roadways. Personal exposures to VOCs and $PM_{10}$ were related to indoor concentrations of beauty shops. According to the questionnaire, hairdressers complained of sore throat, eye irritation, and nervousness as physical symptoms. The measured mean concentrations of respiratory particulates were $30.5ng/m^3$ in indoor, $30.5ng/m^3$ in outdoor and $44.0ng/m^3$ on personal levels. The personal concentration was found higher than indoor and outdoor concentrations. The heavy metals mean concentrations were shown as indoor (Na>Zn>Cr), outdoor (Cr>Zn>Pb), and personal (Na>Cr>Zn) levels. Conclusively, customers as well as workers in the beauty shops might be highly exposed to air pollutants from indoor and outdoor sources. Therefore, proper management should be taken to improve the indoor air quality in beauty shops.