• Journal of Korean Society for Atmospheric Environment
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• v.2 no.1
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• pp.55-72
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• 1986

This study was made to determine the factors involving personal exposure levels of nitrogen dioxide for housewives living in urban area in two seasons, winter and summer. Nitrogen dioxide was measured with a small passive sampler containing triethanolamine. The samplers were set for 24 hours at three points. They were places: on the collar of the housewife to investigate the personal exposure level, near the TV in the living room (indoor level), and near the porch of their house (outdoor level). The subjects recorded the times of cooking using a gas range, using a kitchen ventilator, passive smoking, kerosene heater, total number of minutes at an open window, going out of home, etc.$\ldots. There was an apparent increase in personal exposure level in the case of the unvented heater and also an increase by cooking on a gas range. There was no marked increase in the other situations. There was an increase in the indoor level by cooking on a gas range, only in western style cooking in the winter season. Through these observations, we concluded that personal exposure level of nitrogen dioxide was strongly related to indoor nitrogen dioxide level, and factors involving indoor nitrogen dioxide level seemed different between winter and summer. The most significant difference in nitrogen dioxide level was indoor pollution in the winter and the outdoor environment in the summer. The maximum personal exposure level appeared in the western and tenement house in the winter and the traditional korean house in the summer.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.6
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• pp.613-624
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• 2005

In this study, we investigated the characteristic of volatile organic compounds (VOCs) concentrations in Shiwha area, which were measured using the Open-path FTIR Gas Analyzer. The passive samplers were set for a certain period of time to obtain the average concentration of toluene, ethylbenzene, o-xylene and styrene. In addition, VOCs concentration contour maps were constructed using the Tecplot program to illustrate the VOCs concentration distribution. The residential area showed higher concentrations than the industrial area. And the summer had higher concentration value than the winter. Also, we confirmed that the VOCs concentrations ranged from 2 to several tens ppb in the vicinity of an industry than diffused VOC concentration, whereas those ranged from 0 to 5 ppb in most other areas. It was conferred that the wind change with seasons significantly affects the distribution of VOCs concentrations such as a northwesterly wind in the winter or a southwestern wind in the summer.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.6 s.113
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• pp.90-97
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• 2006

The effects of a green buffer zone to protect a residential area from air pollution from industrial facilities and traffic was examined by analyzing the case of a green buffer zone in the Shiwha industrial complex. The green buffer zone is 175 m wide. The intent was to assess the dispersion patterns of atmospheric air pollutants and the reduction in concentration around the green buffer zone. To measure atmospheric sulfur dioxide$(SO_2)$ and nitrogen dioxide$(NO_2)$ concentration, badge-type passive samplers were used and set up at 76 locations in order to measure the concentration of air pollutants with respect to the spatial dispersion. The weighted mean values of $SO_2\;and\;NO_2$ concentration were $3\~57 ppb\;and\;18\~62 ppb$ and the differences among the green buffer zone, the industrial area and the residential areas were $0.7\~1.1 ppb$. Mean values of atmospheric concentrations of $NO_2$ were similar in industrial and, residential areas and the green buffer zone. Results of the study show that the effect of the green buffer zone on reducing the dispersion of air pollutants was very low. This study also recommends that micro-climate, i.e., wind direction should be considered as a factor for planning and design of green buffer zones.

• Ocean and Polar Research
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• v.29 no.4
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• pp.297-302
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• 2007

Atmospheric levels of polychlorinated biphenyls (PCBs) at the King Sejong station were monitored for one year using passive air samplers. Low-chlorinated PCB homologues were predominant in all samples. PCB levels were observed to decrease with distance from the station, which may indicate that a significant part of PCBs could be of local origin. Although the level of PCBs at the King Sejong station is very low (${\Sigma}_9PCB$ (18, 52, 101, 118, 128, 138, 153, 180, 187): $2.3\;pg\;m^{-3}$) probably due to decrease in the global PCB emissions, it is one order of magnitude higher than a background level in the Antarctic. Based on this preliminary study, more interpretation on PCB data and meteorological conditions is required.

• Journal of environmental and Sanitary engineering
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• v.15 no.4
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• pp.1-3
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• 2000

Indoor carbon monoxide (CO) concentration and personal CO exposures were measured Asan where CO poisoning from twenty coal usage briquette as a domestic fuel to cook and space heating. Twenty-five were houses selected from the Asan area for the survey conducted in February 1997. Newly developed passive CO samplers were placed in the kitchen and living room for the indoor concentration measurement and were worn by homemakers for personal exposure monitoring. The daily average of indoor CO concentration was 16ppm in the kitchen and 10ppm in the living room. The indoor concentration and personal exposures to CO were different in types of the space heating system. House ventilating methods and socioeconomic conditions were also important factors in determining the indoor and personal CO level in Asan.

• Journal of Environmental Impact Assessment
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• v.9 no.1
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• pp.75-86
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• 2000

The purpose of this work was to document the conditions regarding organic solvent exposure to the workers in paint industry. Air concentrations of organic solvents were measured by passive personal samplers and analyzed by a gas chromatography. Urine samples for hippuric test were also taken from 330 workers who have worked at seven domestic factories for more than two years. Amongst 25 organic elements detected in the indoor environment of working places, toluene was the most common element, and methanol showed the highest mean concentration(18.2ppm). A few elements including methylethyl ketone and toluene partially exceeded the Korean Permissible Exposure Limit. A lack of environmental facilities such as exhaust ventilation, automatic cleaning system, and personal safety devices at present work plaus brings about various occupational diseases.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.4
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• pp.452-463
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• 2019

Objectives: The purpose of this study is to evaluate airborne concentrations of volatile organic compounds(VOCs) during nail art practice by college students. Methods: Personal samples for students were measured using passive samplers(OVM 3500) during three kinds of practice, including polish nail, gel nail and acrylic French sculpture at two universities located in Gyeongsangbuk-do Province. We also monitored area concentrations using active samplers and real-time total VOC monitors(ppbRAE 3000). All samples were analyzed with a gas chromatography flame ionized detector. Statistical analysis for monitored data were conducted using a web-based Bayesian toolkit, EXPOSTATS(www.expostats.ca). Results: Twenty-four personal samples and ten area samples were collected and five chemicals(acetone, butyl acetate, ethyl acetate, ethyl methacrylate(EMA) and methyl methacrylate(MMA)) were detected. Acetone was detected in all personal samples and ranged from 2.58 ppm to 50.3 ppm. EMA was detected in all personal and area samples with a maximum concentration of 9.78 ppm during acrylic French sculpture. Personal exposure levels to acetone, butyl acetate and mixtures were significantly higher with high occupant density (p<0.05). Geometric mean (GM) concentrations of 3.61 ppm for EMA personal samples were significantly higher than that of area samples, 1.5 ppm (p<0.05). Since there was no local ventilation, total VOC concentration continued to increase as the practice progressed. Conclusions: In order to minimize VOCs exposure for trainees, it is necessary to introduce a local ventilation system and maintain adequate occupant density.

• Journal of the Korean earth science society
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• v.28 no.5
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• pp.572-584
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• 2007

The quantification of ammonia concentrations has received a lot of scientific attention. Numerous devices for the quantification of $NH_3$ in the ambient air have been developed to provide more technical possibilities for research in abating $NH_3$ emission from various source processes. For the proper quantification of $NH_3$, a number of sampling methods have been discussed by grouping them into different categories based on the principle of functioning. In general, active samplers employ pumps to draw air in, while passive samplers are exposed to air over a certain period of time to obtain integrated signature of $NH_3$. In case of the former, impingers and absorption flasks can be employed simultaneously with suitable absorbents to capture $NH_3$ passing through them. The methods of analysis include both in-situ and laboratory determination. In the laboratory, colorimetric or ion chromatographic methods are generally used for its quantification. In the field, a number of real time analyzers have been proven to be useful. These real time analyzers can be grouped according to their principle of operation. These analyzers may use the principle of spectroscopy (e.g. DOAS), photoacousticics (e.g. photoacoustic monitor) or Chemiluminescence ($NO_x$ analyzer). The automated annular denuder sampling system with on-line analyzer is also suitable for continuous monitoring of ammonia in air.

• Asian Journal of Atmospheric Environment
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• v.12 no.1
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• pp.59-66
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• 2018

This study aims to evaluate the performance of the Air Quality Model (AQM) for the seasonal and spatial distribution of the $NH_3$ concentration in the atmosphere. To obtain observational data for the model validation, observations based on biweekly sampling have been conducted using passive samplers since April 2015 at multiple monitoring sites in the Tokyo metropolitan area. AQM, built based on WRF/CMAQ, was applied to predict the $NH_3$ concentration observed from April 2015 to March 2016. The simulation domain includes the Kanto region, which is the most densely populated area in Japan. Because the area also contains large amount of livestock, especially in its northern part, the density of the $NH_3$ emissions derived from human activities and agriculture there are estimated to be the highest in Japan. In the model validation, the model overestimated the observed $NH_3$ concentration in the summer season and underestimated it in the winter season. In particular, the overestimation in the summer was remarkable at a rural site (Komae) in Tokyo. It was found that the overestimation at Komae was caused by the transportation of $NH_3$ emitted in the northern part of the Kanto region during the night. It is suggested that the emission input used in this study overestimated the $NH_3$ emission from human sources around the Tokyo suburbs and agricultural sources in the northern part of the Kanto region in the summer season. In addition, the current emission inventories might overestimate the difference of the agricultural $NH_3$ emissions among seasons. Because the overestimation of $NH_3$ in the summer causes an overestimation of $NO_3{^-}$ in $PM_{2.5}$ in the AQM simulation, further investigation is necessary for the seasonal variation in the $NH_3$ emissions.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.21 no.4
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• pp.215-221
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• 2011

Objectives: This study was conducted to evaluate the exposure level of hazardous chemical agents for dental technicians in Ulsan. Methods: We measured airborne total dusts and metals such as Nickel, Manganese, Cobalt, and Chromium in 10 dental laboratories by the NIOSH Methods 0500 and 7300, respectively. Methyl methacrylate (MMA), a key ingredient in acrylic resin, was also monitored using passive samplers for long-term sampling and Tenax tubes for short-term sampling. Results: Measured levels of all items were below 10% of the Korean exposure limit except for Nickel. The geometric mean concentration and geometric standard deviation of total dust, Nickel, and MMA were $0.14mg/m^3$ (2.16), $165.3{\mu}g/m^3$ (3.31), and 0.2 ppm (2.5) respectively. Airborne Nickel concentration of two dental laboratories exceeded the exposure limit ($1000{\mu}g/m^3$). The major emission sources of Nickel were metal trimming and casting processes. Conclusions: We found that Nickel, a carcinogen, should be controled most urgently to protect dental technicians.