• 설비공학논문집
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• 제22권11호
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• pp.735-744
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• 2010

An efficient code has been developed to predict dispersion of indoor air pollutants. The computing capability of the code has been compared with that of a commercial code in a benchmark test. After that, the code has been employed to compute dispersion of a pollutant released from a new furniture, a kind of Sick Building Syndrome(SBS). A sofa which generates formaldehyde is implemented by using an immersed boundary method. Large Eddy Simulation (LES) is employed to obtain time-dependent velocity and concentration fields. LES has been regarded as an academic tool, but the newly-developed code reveals a possibility of application of LES to practical problems, especially dispersion of indoor pollutants.

• 펄프종이기술
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• 제47권4호
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• pp.151-159
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• 2015

Paper records were generally degraded by some factors from atmospheric environments, like temperature, relative humidity or air pollutants. In this study, the degradation behavior of paper records by single or mixed gases of $NO_2$, $SO_2$, HCHO and TVOC was evaluated. The mechanical, optical and chemical properties of 4 kinds of paper (acid and neutral-based printing paper, traditional Hanji, and filter paper) were directly and indirectly affected by gaseous harmful materials. The brightness and $L^*$ value in all papers were slightly increased by accelerated aging under gaseous HCHO and TVOCs, but highly decreased by conditions under gases $NO_2$ and $SO_2$. The optical properties of paper records were most vulnerable in acid-based paper and high stable in filter paper and traditional Hanji by air pollutant degradation. The aging treatments under mixed gas pollutants including $NO_2$ resulted in decrease of physical, mechanical and optical properties of paper, so it was supposed that the concentration of $NO_2$ gas would be strictly controlled for optimum indoor air quality management in domestic storage centers for paper records.

• KIEAE Journal
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• 제8권1호
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• pp.25-30
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• 2008

This study aims at examining the reduction of indoor air contaminants by plants placed in an indoor space. The effect of reducing the concentration of air contaminants by three species of plants was studied in a full-scale mock-up model. Field measurements were performed using Aglaonema brevispathum, Pachira aquatica and Ficus benjamiana which were verified as air-purifying plants by NASA. Their positions and amount were controlled. Two conditions for the amount of plants(10%, 5%) and positions(sun-shine, scatter) were used in two separate rooms whose dimensions are identical. The concentration of Volatile Organic Compounds(VOCs) was monitored three hours after the plants were placed and three days after the plants were placed. The variations of concentration of Benzene, Toluene, Etylbenzene, Xylene, Stylene and Formaldehyde, which are all known as the major elements of Volatile Organic Compounds were monitored. The more plants were used, the more a reduction of indoor air contaminants occurred. The effect of reducing the concentration of air contaminants increased when the amount of plants increased.

• 한국환경보건학회지
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• 제50권3호
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• pp.191-200
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• 2024

Background: Busan is a rapidly industrializing city with many mixed residential and industrial areas. Fine dust emissions from mobile pollution sources such as ships and vehicles are particularly high in Busan. Objectives: This study analyzed the spatial distribution of air pollutants over the past three years and identified the impact of air pollutants through mobile source data in Busan. Methods: We obtained air pollutant data on fine particulate matter (PM₁₀), ultrafine particulate matter (PM_2.5), nitrogen dioxide (NO₂), sulfurous acid gas (SO₂), and ozone (O₃) for the last three years (source: airkorea.or.kr) and analyzed the spatial distribution using SAS 9.4 and Surfer 23. For the mobile pollutant data, we used CCTV data from major intersections in Busan to identify truck and car traffic, and visualized traffic density with QGIS. Results: The analysis of the concentration of air pollutants over three years (2020~2022) showed that all were lower than the annual environmental standards with the exception of PM_2.5. PM₁₀ and PM_2.5 were found to be highly concentrated in the western part of the area, while NO₂ was high in the port area of Busan and SO₂ was high in the western part of the area and near the new port of Busan. In the case of O₃, it was high in the eastern part of the city. The traffic volume of freight vehicles by intersection was concentrated in the West Busan area, and the traffic volume for all cars was also confirmed to be concentrated at "Mandeok Intersection" located in the West Busan area. Conclusions: This study was conducted to determine the relationship between air pollutants emitted from motor vehicles and the distribution of air pollutants in Busan. The spatial distribution of PM₁₀ and PM_2.5 correlates with traffic volume, while high concentrations of SO₂ and NO₂ near the port are associated with ship emissions.

• 한국환경과학회지
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• 제18권5호
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• pp.569-578
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• 2009

Aircraft Measurements of gaseous pollutants($SO_2$, NOx and $O_3$) in the Yellow Sea area, were carried out on 1997-2007. Main measurement site in 124$^{\circ}$-127$^{\circ}$E, 35$^{\circ}$-37$^{\circ}$N (in the Yellow Sea), have been done along the paths classified vertically and zonally. To understand how the air stream affects Long-range transboundary pollutants in Northease Asia (LTP), the tracks of pollutants in northeast Asia have been analyzed by dividing into 6 different regions(regions I-V and L). Compared with Korea's local sources and western north Pacific influenced by the Yellow Sea, when the air stream from region II is dominant, the $SO_2$ concentrations are 3-6times higher. In region II and III, $SO_2$ concentrations are represented highest at 25.0 and 14.7 ppb, respectively. However, in other regions, $SO_2$ concentration was recorderd the highest at 1.1-3.8 ppb, which is 7-15% higher then the highest one over the region II and III. During 1997-2007, the mean amount of incoming pollutants is 0.162 $ton/km{\cdot}hr$ exceeding about 5-times mean amount of outgoing pollutants over the West Sea. During the observed period, the amount of incoming and outgoing $SO_2$ over the Yellow Sea is the highest in winter, at 0.224 $ton/(km{\cdot}hr)$ and 0.120 $ton/(km{\cdot}hr)$, respectively.

• 한국대기환경학회지
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• 제15권5호
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• pp.567-574
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• 1999

Volatile organic Compounds(VOC) were measured at an industrial site in Ulsan in 1997 and 1998. Twenty-four hour integrated ambient air samples were collected in 6 L SUMMA canisters during the periods of June 3 to 8, 1997 and June 12 to 17, 1998. The daily mean concentrations of the total $C_2-C_9$ VOC in 1998 were about one third of those in 1997. This decrease of VOC levels may be attributable to the measures to control the emissions of VOC and the decrease of the plant operation. The decrease in the concentrations of oxygenated hydrocarbons and alkenes, especially, contributed to the decrease of the total VOC concentrations in 1998. Lowever concentrations of alkenes compared to aromatics in 1998 were due to the decrease of ethylene and propylene. In the present study, methanol (12.0 ppb) was the most abundant species, followed by acetone (10.1 ppb), propane (6.0 ppb), and vinyl chloride (5.9 ppb). The total concentrations of hazardous air pollutants (HAPs) in 1998 were reduced compared to those in 1997. However, this decrease is due to the drastic decrease of the concentration of methanol. Except methanol, the concentrations of HAPs have not varied much. It is suspected that the VOC control strategy for the Ulsan industrial area has been successful for reducing the total VOC levels but might not be effective in reducing the concentrations of HAPs.

• 한국대기환경학회지
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• 제14권3호
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• pp.229-236
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• 1998

Visibility is a good indicator of comprehensive alto quality. The prevailing visibility in Seoul is no better than the past although the average concentration of SO2 and TSP (total suspended particulate) has decreased quite significantly in the past decade, owing to the government efforts to reduce the emission. Then, a question arises why visibility has not been improved. In order to answer this question we have investigated which components of air pollutants are most responsible for the visibility degradation in Seoul. Analysis on the visibility vs the aerosol sixte distribution measured by an optical particle counter shows that the particles of the size interval between 0.5mm and 2.5mm are most responsible for the visibility degradation. Among the criteria air Pollutants, NOB concentration is found to be moot responsible, rather than PM10. ton analysis of the particulate collected by a high volume sampler shows that the nitrate component increases more significantly than other ions when visibility becomes very poor. Therefore, we conclude that the major causes of visibility degradation in Seoul are the increase of NOB, nitrates and the particles of the size range between 0.5mm and 2.5mm.

• 한국대기환경학회지
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• 제9권2호
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• pp.147-153
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• 1993

From March 1990 to August 1991, every each 5mm bulk precipitation samples were collected at one residental area in Taejon City to investigate chemical characteristics of acid rain. Major ion concentrations of rain samples $(pH, SO_4^{2-}, NO_3^-, CL^-, NH_4^+, Na^+, K^+, Ca^{2+}, Mg^{2+})$ were analysed and compared with the concentration of air pollutants (T. S. P, $SO_2, NO_x$) that were measured by Ministry of Environment. The results of statistical analysis are as followings. Rain pH was relatively high on October and January and relatively low on August, November and February. Major anion is sulfate, and it's concentration is 2.36 times higher than nitrate's, and major cations are ammonium, sodium and calcium ion. Monthly variation of sulfate and calcium concentrations are higher than the others. Ion concentration and rain pH were correlated negatively with rainfall amount. Major ions in rain samples were $SO_4^{2-}, NO_3^-, NH_4^+, Ca^{2+}$ and regression equations are proposed by multiple regression of measured data. Also, regression equation between air pollutants(T. S. P, $SO_2$) and $SO_4^{2-}, Na^+, K^+, Ca^{2+}, Mg^{2+} ions in rain samples were made. From this wer can predict rain pH.

• KIEAE Journal
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• 제17권5호
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• pp.33-41
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• 2017

Purpose: Indoor air quality in residential buildings needs to be evaluated over the long term. In previous research, there has been an attempt to perform the health risk assessment of pollutants by using numerical models as a method of long-term evaluation. However, the numerical model of this precedent study has limitations that do not reflect the actual concentration distribution. Therefore, this study introduces the CRPS index, constructs a numerical model that can reflect the concentration distribution, and then presents a more accurate health risk assessment method using it. At this time, the pollutants are toluene, which is a typical material released from building materials. Method: CRPS index was applied to existing numerical model to reflect concentration distribution. This was used to calculate concentrations at adult breathing area and to use them for exposure assessment in a health risk assessment. After that, we entered adult data and conducted a health risk assessment of toluene. Results: The non-carcinogenic risk of toluene was calculated to be 0.0060. This is 5% smaller than the existing numerical model, meaning that it is more accurate to predict the pollutant risks. This value is also lower than the US EPA reference value of 1. Therefore, under the conditions of this study, long-term exposure of adults to toluene has no impact on health.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.1220-1224
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• 2008

Because of the high airtightness and insulation of the building, indoor environment has been largely polluted resulted from insufficient ventilation and occurrence of new air pollutant. These factors have made worse indoor air quality and caused symptoms of the SHS(Sick House Syndrome), MCS(Multi Chemical Sensitivity). The purpose of this study is to present the fundamental strategies for improving the Indoor Air Quality(IAQ) in newly-constructed apartment buildings. To investigate the concentration of indoor air pollutants such as Formaldehyde and VOCs, the field measurement were conducted.