• Journal of Korean Society for Atmospheric Environment
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• v.28 no.4
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• pp.435-445
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• 2012

The aim of this study is to understand the characteristics of volatile oranic compounds (VOCs) and provide information about the present Indoor Air Quality (IAQ) at residential apartments. All samples were collected in 60-min interval using the tenax absorption trap between May, 2011 and February, 2012. And the effects of environmental factors such as temperature, humidity and construction characteristics were analyzed in relation to the measured concentrations. The results of this study showed that the mean concentration of VOCs was lower than the Ministry of the Environment's standards for maintenance of indoor air quality. The correlation analysis showed that ethylbenzene and xylene (r=0.916, p<0.01), toluene and ehtylbenzene (r=0.810, p<0.01), toluene and xylene (r=0.803, p<0.01) and toluene and styrene (r=0.588, p<0.01) were significant. The result of regression analysis was found that the influenece factors associated with the concentration of VOCs were the age and location of the apartment, remodeling, the temperature and the season.

• Journal of Environmental Analysis, Health and Toxicology
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• v.21 no.4
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• pp.264-280
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• 2018

In this study, volatile organic compounds (VOCs) were measured using a proton transfer reaction-time of flight-mass spectrometer (PTR-ToF-MS) at the Seoul Metropolitan Area Intensive Monitoring Station (SIMS) in Korea during the summer season of 2018. The results revealed that oxygenated VOCs (OVOCs) contributed a large fraction (83.6%) of the total VOCs, with methanol being the most abundant constituent (38.6%). The VOCs measured at SIMS were strongly influenced by local conditions. Non-volatile organic compounds (NVOCs), such as pinene, increased due to northeasterly wind direction in the morning, and OVOCs and anthropogenic VOCS (AVOCs) increased with northwesterly wind direction during the daytime. This was the result of the eastward location of Bukhansan National Park and the westward location of urban area from the SIMS location. The VOCs included abundant oxidized forms of VOCs, which can affect the generation of fine dust through various response pathways in the atmosphere. The real-time measurement technique using PTR-ToF-MS suggested in this study is expected to contribute to an improved scientific understanding of high-concentration fine dust events because the high temporal resolution makes it possible to analyze the variations of VOCs reflected in dynamic events.

• KIEAE Journal
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• v.5 no.1
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• pp.51-57
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• 2005

In this study, time-dependent concentration variations of VOCs from fixed furniture and Ondol floor widely used as finishing material of the floor were measured, and prediction equations were developed based on the measured results. VOCs were measured and analyzed based on EPA TO-17 and NIOSH 1500, 1501 method respectively, and GC/FID were used for the analysis of VOCs concentration. Measurements were carried out for 10 days after the installation of furniture and for 40 days after the installation of the floor in the residence constructed more than 10 years ago. In both case of floor and furniture installation, time-dependent concentration decay of VOCs can be properly converted into logarithmic scale. Especially in case of furniture, toluene showed the highest concentration and took longest time to decay. As a result of the prediction of VOCs concentration decay under different air change rate using estimated equations, concentration decay rate of indoor VOCs increased rapidly as the air change rate also increased.

• Environmental Engineering Research
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• v.24 no.4
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• pp.600-607
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• 2019

Volatile organic compounds (VOCs) are released from various sources and are unsafe for human health. Porous materials are promising candidates for the adsorption of VOCs owing to their increased ratio of surface area to volume. In this study, activated carbon (AC) impregnated cellulose acetate (CA) electrospun mats were synthesized using electrospinning for the removal of VOCs from the air mixture of ACs, and CA solution was electrospun at different proportions (5%, 10%, and 15%) in a single nozzle system. The different AC amounts in the electrospun mats were distributed within the AC fibers. The adsorption capacities were measured for acetone, benzene, and dichloromethane, using quartz crystal microbalance. The results elicited an increasing adsorption capacity trend as a function of the impregnation of ACs in the electrospun mats, while their capacities increased as a function of the AC concentration. Dichloromethane resulted in a faster adsorption process than acetone and benzene owing to its smaller molecular size. VOCs were desorbed with the N₂ gas purging, while VOCs were adsorbed at higher temperatures owing to the increased vapor pressures. The adsorption analysis using Dubinin-Astakhov equation showed that dichloromethane is more strongly adsorbed on mats.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.227-228
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• 2003

대기 오염에 관한 연구가 진행되면서 광화학반응에 기여도가 높고, 인체에 직, 간접적으로 영향을 미치는 Volatile organic carbons(이하 VOCs)를 측정하는데 많은 연구가 진행되어져 오고 있다. Gas chromatography와 같은 sampling method에 의한 농도 측정 방법은 정확한 농도를 측정 할 수 있다는 장점은 있지만, 대기 중 광화학반응 기작을 연구하는데 있어서 오존과 VOCs를 포함한 화학종들의 공간적, 시간적인 농도 변화를 분석하는데 한계를 가지고 있다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.274-275
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• 2002

일반시민의 생활수준 향상에 따른 자동차의 중가와 각종 산업분야의 산업활동 증가는 대기중 휘발성 유기화합물(Volatile Organic Compounds;이하 VOCs)의 증가를 가져왔다. VOCs는 오존층 파괴 및 지구 온난화 가중, 광화학스모그 생성 등 환경적 측면과 발암성 및 유전독성을 내포하여 인체에 영향을 주는 것으로 알려져 그 중요성이 부각되고 있다. 특히 공단지역의 VOCs 및 악취 둥 오염피해는 90년대 후반부터 규제가 강화되어, 여천과 울산공업단지의 경우 VOCs의 특별대책지역으로 규제되어 있다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.356-357
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• 2002

Paint Booth 등의 공정에서 배출되는 휘발성유기화합물(volatile organic compounds, VOCs)등 유해물질로 인한 대기오염의 증가와 이의 이동 확산에 따른 수질 및 토양오염으로 지역 주민의 호흡기 또는 음식물을 통한 노출 위해성이 증가하고 있다. 석유화학단지 및 주변에서 발생되는 VOCs등 유해물질은 발암성 등 만성적으로 환경성 질환을 유발할 가능성이 매우 높다. (중략)

• Journal of Korean Society for Atmospheric Environment
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• v.26 no.2
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• pp.161-176
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• 2010

We examined high ozone episodes observed during the intensive measurement periods (11 May~21 June and 30 July~11 August 2009) in the Gulf of Gwangyang. During that period, there were a few events (or days) in which 1 hr averaged ozone concentrations were greater than 100 ppbv. The analysis of ozone budget and photochemical characteristics related to the ozone production was carried out using a photochemical box model. Ozone sensitivity to $NO_x$ and VOCs was also examined in the study area during the measurement period. Diurnal variation of ozone during the episodes was similar to that of odd hydrogen radicals ($HO_2,CH_3O_2$, and $RO_2$), suggesting significant correlation with photochemical production of ozone during the episodes. In general, ozone concentration in the study area during the measurement period was sensitive to VOCs, whereas ozone was sensitive to $NO_x$ under certain conditions. Ozone sensitivity assessment using a radical budget analysis and $NO_x$/VOCs-control strategy was consistent with that using indicator species ($H_2O_2/HNO_3$ ratio).

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.12
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• pp.1123-1131
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• 2005

The floor material is known as the most influential emission source of the residential building, because most floor material is made of wood compound and adhesive like a plywood flooring. Moreover, floor heating system keeps the inside temperature of the material high. As the emission of hazardous chemical compound from the construction material is influenced by many factors, it is necessary to analyze the emission characteristics of the floor material to improve IAQ. In this study, numerical analysis is performed to investigate the emission characteristics of the floor material affected by several factors such as temperature, air exchange rate, initial concentration, and internal diffusion coefficient. A simulation program is also written based on the mass transfer theory. The simulation results show that there is some level of difference on the TVOC concentration when each of the factors is variable.

• Analytical Science and Technology
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• v.34 no.1
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• pp.23-35
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• 2021

In order to measure the volatile organic compounds (VOCs) of a sample which is too large to use commercially available chamber, a stainless steel vacuum chamber (VC) (with an internal diameter of 205 mm and a height of 50 mm) was manufactured and the temperature of the chamber was controlled using an oven. After concentrating the volatiles of the sample in the chamber by helium gas, it was made possible to remove residual volatile substances present in the chamber under reduced pressure ((2 ± 1) × 10-2 mmHg). The chamber was connected to a purge & trap (P&T) using a 6 port valve to concentrate the VOCs, which were analyzed by gas chromatography-mass spectrometry (GC-MS) after thermal desorption (VC-P&T-GC-MS). Using toluene, the toluene recovery rate of this device was 85 ± 2 %, reproducibility was 5 ± 2 %, and the detection limit was 0.01 ng L-1. The method of removing VOCs remaining in the chamber with helium and the method of removing those with reduced pressure was compared using Korean drinking water regulation (KDWR) VOC Mix A (5 μL of 100 ㎍ mL-1) and butylated hydroxytoluene (BHT, 2 μL of 500 ㎍ mL-1). In case of using helium, which requires a large amount of gas and time, reduced pressure ((2 ± 1) × 10-2 mmHg) only during the GC-MS running time, could remove VOCs and BHT to less than 0.1 % of the original injection concentration. As a result of analyzing volatile substances using VC-P&T-GC-MS of six types of cell phone case, BHT was detected in four types and quantitatively analyzed. Maintaining the chamber at reduced pressure during the GC-MS analysis time eliminated memory effect and did not affect the next sample analysis. The volatile substances in a cell phone case were also analyzed by dynamic headspace (HT3) and GC-MS, and the results of the analysis were compared with those of VC-P&T-GC-MS. Considering the chamber volume and sample weight, the VC-P&T configuration was able to collect volatile substances more efficiently than the HT3. The VC-P&T-GC-MS system is believed to be useful for VOCs measurement of inhomogeneous large sample or devices used inside clean rooms.