Shin-Do Kim

A Comparative Study on PM 10 Source Contributions in a Seoul Metropolitan Subway Station Before/After Installing Platform Screen Doors

Almost five million citizens a day are using subways as a means of traffic communication in the Seoul metropolitan. As the subway system is typically a closed environment, indoor air pollution problems frequently occurs and passengers complain of mal-health impact. Especially is well known as one of the major pollutants in subway indoor environments. The purpose of this study was to compare the indoor air quality in terms of and to quantitatively compare its source contributions in a Seoul subway platform before and after installing platform screen doors (PSD). samples were collected on the J station platform of Subway Line 7 in Seoul metropolitan area from Jun. 12, 2008 to Jan. 12, 2009. The samples collected on membrane filters using mini-volume portable samplers were then analyzed for trace metals and soluble ions. A total of 18 chemical species (Ba, Mn, Cr, Cd, Si, Fe, Ni, Al, Cu, Pb, Ti, , , , , , , and ) were analyzed by using an ICP-AES and an IC after performing proper pre-treatments of each sample filter. Based on the chemical information, positive matrix factorization (PMF) model was applied to identify the source of particulate matters. for the station was characterized by three sources such as ferrous related source, soil and road dust related source, and fine secondary aerosol source. After installing PSD, the average concentration was decreased by 20.5% during the study periods. Especially the contribution of the ferrous related source emitted during train service in a tunnel route was decreased from 59.1% to 43.8% since both platform and tunnel areas were completely blocked by screen doors. However, the contribution of the fine secondary aerosol source emitted from various outside combustion activities was increased from 14.8% to 29.9% presumably due to ill-managed ventilation system and confined platform space.

Identification of PM 10 Chemical Characteristics and Sources and Estimation of their Contributions in a Seoul Metropolitan Subway Station

Since the underground transportation system is a closed environment, indoor air quality problems may seriously affect many passengers` health. The purpose of this study was to understand characteristics in the underground air environment and further to quantitatively estimate source contributions in a Seoul Metropolitan subway station. The was intensively collected on various filters with aerosol samplers to obtain sufficient samples for its chemical analysis. Sampling was carried out in the M station on the Line-4 from April 21 to 28, July 13 to 21, and October 11 to 19 in the year of 2010 and January 11 to 17 in the year of 2011. The aerosol filter samples were then analyzed for metals, water soluble ions, and carbon components. The 29 chemical species (OC1, OC2, OC3, OC4, CC, PC, EC, Ag, Al, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Si, Ti, V, Zn, , , , , , , , ) were analyzed by using ICP-AES, IC, and TOR after proper pretreatments of each sample filter. Based on the chemical information, positive matrix factorization (PMF) model was applied to identify the sources and then six sources such as biomass burning, outdoor, vehicle, soil and road dust, secondary aerosol, ferrous, and brakewear related source were classified. The contributions rate of their sources in tunnel are 4.0%, 5.8%, 1.6%, 17.9%, 13.8% and 56.9% in order.

Concentration and Properties of Particulate Matters (PM 10 and PM 2.5 ) in the Seoul Metropolitan

Seoul subway plays an important part for the public transportation service in Seoul metropolitan area. As the subway system is typically a closed environment, frequent air pollution problems occurred and passengers get malhealth impact. Especially particulate matters (PM) is well known as one of the major pollutants in subway environments. The purpose of this study was to compare the concentrations of and in the Seoul subway system and to provide fundamental data in order to management of subway system. and samples were collected in the M station platform and tunnel of Subway Line 4 in Seoul metropolitan and in an outdoor location close to it from Apr. 21, 2010~Oct. 27, 2013. The samples collected on teflon filters using and mini-volume portable samplers and PM sequential sampler. The PM contributions were (outdoor), (platform) and (tunnel) for , and (outdoor), (platform) and (tunnel) for . The levels inside stations and outdoors are poorly correlated, indicating that levels in the metro system are mainly influenced by internal sources. In this study, we compared PM concentrations before and after operation of ventilation and Electrostatic Precipitator (EP). Despite the increased PM concentration at outdoor, concentration at platform and tunnel showed the 31.2% and 32.3% reduction efficiency after operation the reduction system. The overall results of this study suggest that the installation and operation of the ventilating system and EP should have served as one of the important components for maintaining the air quality in the subway system.

Analysis of Energy Consumption Pattern and Greenhouse Gas Emission in the Academic Facility

Self-management plan for GHG (Greenhouse Gas) reduction should be prepared in academic facilities, which occupy a large amount of energy consumption. In this study, a university was chosen as one of the major academic facilities and its energy consuming pattern and GHG emission were analyzed. The results have shown that annual CO2 emission from university buildings was 10,452 ton-CO2 (0.65 ton-CO2/m), and dependent upon 78.0% electricity, 20.5% LNG and 1.5% oil, respectively as energy sources. According to more detail analysis by usage of energy consumption, appliances occupies 36.7% followed by gas heating (18.9%), lighting (18.6%), heating with electricity (12.5%), cooling with electricity (10.2%), transportation (1.5%), gas cooling (1.2%) and cooking (0.4%). Furthermore, annual CO2 emissions per unit area and a student by electricity usage were evaluated to 51.30 kg-CO2/m and 981.86 kg-CO2/capita, respectively and those by LNG usage were 14.61 kg-CO2/m and 241.01 kg-CO2/capita.

Studies on the Spatial Analysis for Distribution Estimation of Radon Concentration at the Seoul Area

Radon is an invisible, odorless, and radioactive gas. It is formed by the disintegration of radium, which is a decay product of uranium. Some amounts of radon gas and its products are present ubiquitously in the soil, water, and air. Particularly high radon levels occur in regions of high uranium content. Although radon is permeable into indoor environment not only through geological features (bed rock and permeability) but also through the construction materials and underground water, the radiation from the geological features is generally main exposure factor. So there can be a problem in a certain space such as the underground and/or relatively poor ventilation condition. In this study, a GIS technique was used in order to investigate spatial distribution of radon measured from sub- way stations of 1 thru 8 in Seoul, Korea in 1991, 1998, 2001, and 2006. Spatial analysis was applied to reproduce the radon distribution. We utilized spatial analysis techniques such as inverse distance weighted averaging (IDW) and kriging techniques which are widely used to relate between different spatial points. To validate the results from the analyses, the jackknife technique for an uncertainty test was performed. When the number of measuring sites was less than 100 and also when the number of omitted sites increased, the kriging technique was better than IDW. On the other hand, when the number of sites was over 100, IDW technique was better than kriging technique. Thus the selection of analytical tool was affected sensitives by the analysis based on the number of measuring sites.

The Qualitative Rate Estimation of PAHs in Carbon Compounds of Particles in Vehicles Exhaust Gas

Since the emergence of domestically produced automobiles in 1964, the number of automobiles in circulation in South Korea has increased constantly. With this rapidly increasing number of automobiles, automobile-induced environmental pollution has become an issue of great concern, especially with regard to air pollution. Of the carbon composites contained in automobile exhaust gas, PAHs are known to be carcinogenic and highly deleterious to humans and thus need to be urgently mitigated. To address this issue of PAHs, this study was conducted to estimate qualitative of particulate PAHs contained in carbon composites in automobile exhaust gas, by capturing all particulate matter discharged from the latter. To allow for differentiated analyses, the automobiles investigated were divided into 4 groups: gasoline vehicle, motocycle, diesel vehicle, and LPG vehicle. Samples were analyzed using two methods. First, in-depth analysis was performed on organic carbon (OC) and elemental carbon (EC) composites with analysis parameters, using the Thermal Optical Transmittance Method (NIOSH 5040). Second, for the examination of particulate PAHs, GC/MSD was used to analyze the 16 PAH species specified by the Environmental Protection Agency (EPA). The analyses yielded the findings that diesel vehicles had the highest mass concentration (2,007μg/ *Corresponding author. Tel : +82-(0)2-6490-2860, E-mail : sdkim@uos.ac.kr 기술자료