• Proceedings of the SAREK Conference
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• 2008.06a
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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.

• Applied Chemistry for Engineering
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• v.30 no.5
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• pp.633-638
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• 2019

Indoor air quality underground facilities are not equipped for the removal of volatile organic compounds (VOCs) and they are usually treated by diffusion methods such as ventilation. In this study, an adsorption filter was prepared using various coating methods such as carbon nano fiber (CNF) and dip coating. As a result, the adsorption performance was improved by 2 to 20 times or more compared to that of using the metal foam support. This is maybe due to the enhancement of pore distribution which was confirmed by SEM. In addition, the adsorption performance was 13.95 mg/g by adding lignin, and also an average adsorption performance of 13.25 mg/g was maintained after washing indicating that a highly durable adsorption filter material was prepared. It can be suggested that the developed adsorption filter material can be a potential solution that can fundamentally control VOCs, not via the concentration reduction of mechanical ventilation in underground facilities.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.27 no.1
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• pp.23-37
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• 2017

Objectives : This study was conducted to evaluate the level of exposure to volatile organic compounds (VOCs) among workers handling rust preventive oils. Methods : A total of 30 bulk samples and 54 personal air samples were collected using diffusive samplers at 22 workplaces handling rust preventive oils in Daegu and Gyongsangbuk-do Province from March to October 2013. We also investigated detailed information on the related work conditions, such as kinds of products, handling methods, local exhaustive ventilation systems, and the status of the wearing personal protective equipment. All bulk samples and air samples were analyzed using gas chromatography mass spectrometry (GC-MS) to identify components to which workers potentially were exposed. Quantitative airborne concentrations of VOCs were confirmed using gas chromatography with flame ionized detectors. Results : In terms of qualitative analyses for the 30 bulk samples, we found carcinogenic, mutagenic and reproductive toxic(CMR) substances such as butane(carcinogenic Group 1A, mutagenic Group 1B), butoxy ethanol(carcinogenic Group 2), cumene (carcinogenic Group 2), ethyl benzene(carcinogenic Group 2), methyl isobutyl ketone(carcinogenic Group 2) and toluene (reproductive toxic, Group 2). As a result of full-shift based personal air samples, eight substances such as n-hexane, n-heptane, octane, nonane, decane, toluene, ethyl benzene and xylene were detected. Among them, n-hexane and n-heptane were detected in all of 54 air samples with $13.13mg/m^3$ and $8.61mg/m^3$ of maximum concentration, respectively. The level of airborne concentration from all of samples were bellow the occupational exposure limit in Korea. Conclusions : Based on the results of this study, workers handling rust preventive oils could be exposed to CMR substances contained in rust preventive oils and n-hexane and n-heptane were found as the most frequent sources of VOC exposure.

• Safety and Health at Work
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• v.2 no.3
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• pp.210-217
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• 2011

Objectives: The purpose of this study was to measure the concentration of volatile organic compound (VOC)s originated from the chemicals used and/or derived from the original parental chemicals in the photolithography processes of semiconductor manufacturing factories. Methods: A total of four photolithography processes in 4 Fabs at three different semiconductor manufacturing factories in Korea were selected for this study. This study investigated the types of chemicals used and generated during the photolithography process of each Fab, and the concentration levels of VOCs for each Fab. Results: A variety of organic compounds such as ketone, alcohol, and acetate compounds as well as aromatic compounds were used as solvents and developing agents in the processes. Also, the generation of by-products, such as toluene and phenol, was identified through a thermal decomposition experiment performed on a photoresist. The VOC concentration levels in the processes were lower than 5% of the threshold limit value (TLV)s. However, the air contaminated with chemical substances generated during the processes was re-circulated through the ventilation system, thereby affecting the airborne VOC concentrations in the photolithography processes. Conclusion: Tens of organic compounds were being used in the photolithography processes, though the types of chemical used varied with the factory. Also, by-products, such as aromatic compounds, could be generated during photoresist patterning by exposure to light. Although the airborne VOC concentrations resulting from the processes were lower than 5% of the TLVs, employees still could be exposed directly or indirectly to various types of VOCs.

• Horticultural Science & Technology
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• v.33 no.5
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• pp.751-762
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• 2015

This study was performed to investigate the stability of soil moisture in controlling air ventilation rate within a horizontal biofilter, and to compare removal efficiency (RE) of indoor air pollutants including fine dust, volatile organic compounds (VOCs), and formaldehyde (HCHO), depending on whether dieffenbachias (Diffenbachia amoena) were planted in the biofilter. The relative humidity, air temperature, and soil moisture contents showed stable values, regardless of the presence of D. amoena, and the plants grew normally in the biofilter. REs for number of fine dust particles (PM10 and PM2.5) within the biofilter filled with only soil were at least 30% and 2%, respectively. REs for number of fine dust particles (PM10 and PM2.5) within the biofilter including the plants were above 40% and 4%, respectively. RE for fine dust (PM10) weight was above 4% and 20%, respectively, in the biofilter containing only soil or soil together with plants. In the case of the biofilter filled with only soil, REs for xylene, ethylbenzene, toluene or total VOC (T-VOC) were each more than 63%; however, REs for benzene and formaldehyde (HCHO) were above 22% and 38%, respectively. In the biofilter with the plants, REs for xylene, ethylbenzene, toluene, and T-VOC were each above 72%, and REs for benzene and HCHO were above 39%. Thus, RE of the biofilter integrated with plants was found to be higher for volatile organic compounds than for fine dust. Hence, the biofilter was very effective for indoor air quality improvement and the effect was higher when integrated with plants.

• Architectural research
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• v.7 no.1
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• pp.19-26
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• 2005

Unlike other countries, Korea uses various kinds of wall-paper as finishing material. Conventional wall-paper consists of paper and vinyl, and petrochemical ink is used for the decoration of the surface. Adhesive is used to paste the wall with the wall-paper, which emit substantial amounts of VOCs and formaldehyde. In this study, VOCs characteristics emitted from specimens made of concrete, mortar, gypsum board and wall-paper were investigated using small chamber method. Moreover, concentration and emission factor of BTEX(Benzene, Toluene, Ethylbenzene, m,p,o-Xylene) and TVOC were investigated, and concentration and emission factor decay were estimated. As a result of the prediction, both time-dependent concentration decay and cumulative concentration can be converted into the logarithmic scale. Furthermore, prediction equations were developed from the experimental results under accurately controlled experimental conditions. Therefore, there may be difference if the estimated equations are directly applied to real buildings. Further research should be done on the generalization of the developed prediction equations.

• Journal of the Korean Society of Safety
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• v.21 no.2 s.74
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• pp.150-157
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• 2006

Sick Building Syndrome (SBS) is an illness symptom such as irritation of eyes, skin eruption and vomit ing in newly constructed buildings. It is mainly due to the harmful gases from the materials installed in building such as Volatile Organic Compounds (VOCs), Semivolatile Organic Compounds (SVOCs), floating bacteria, fungi, fungal spores and viruses, human bioeffluents in many modem buildings. The general ways to improve the Indoor Air Quality (IAQ) are ventilating, utilizing eco-material without harmful gases and reducing or removing harmful gases through additional treatment to the building materials. This study aimed to improve the Indoor Air Quality(IAQ) by applying surface coating on the building materials and to make safe living environments through the analysis of air quality before and after surface coating treatment in buildings.

• Journal of Environmental Health Sciences
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• v.49 no.2
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• pp.78-88
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• 2023

Background: Exposure to volatile organic compounds (VOCs) can have acute and chronic health effects on human beings in general and in working environments. In particular, VOCs are often emitted in large quantities in industrial settings. In such circumstances, there is a need to improve the indoor air quality at workplaces. Objectives: The purposes of this study were to verify the effectiveness of air cleaning devices in workplaces and provide alternative solutions for improving working environments. Methods: Personal exposure and area level of VOCs for workers were evaluated in a car-part adhesive process before and after installing an air cleaning device with a TiO₂-coated filter. Passive samplers and direct reading instruments were used to collect and analyze the VOCs, and the removal efficiency and improvement of air quality were evaluated. We also calculated the exposure index (EI) to assess the risk level in the workplace. Results: The removal efficiency for VOCs through the installation of the air cleaning device was approximately 26.9~69.0% as determined by the concentration levels before and after installation. The measured substances did not exceed the exposure limits for the work environment and the EI was less than 1. However, carcinogenic substances such as benzene, formaldehyde, carbon tetrachloride, and trichloroethylene were detected. Conclusions: The application of an air cleaning device can be a solution for controlling the indoor air quality in a workplace, particularly in cases where ventilation systems cannot be installed due to process limitations.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.23 no.3
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• pp.222-228
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• 2013

Objectives: The indoor air quality of newly-built (NC) and remodeled (RC) school classrooms was assessed. The primary aim was to show correlations between volatile organic compounds (VOCs) and formaldehyde (HCHO) pollutant levels. Methods: This study investigated the indoor air concentrations of VOCs and HCHO at 26 sites of newly built and 68 sites of remodeled classrooms located in South Gyeongsang Province between 2010 and 2012. VOCs in the indoor air were determined by adsorbent tube (Tenax TA) and automatic thermal desorption coupled with GC-MS analysis. Target analytes were five VOCs: benzene, toluene, ethylbenzene, xylene, and styrene. HCHO was collected with a 2,4-DNPH cartridge and analyzed by HPLC. Conclusions: This study estimated that indoor VOCs and HCHO concentrations in the classrooms were mainly affected by interior building materials and classroom equipment. For proper indoor air quality in schools, classroom air should be improved through reduction of hazardous materials by adequate ventilation, selecting environmental friendly materials, etc.

• Asian Journal of Atmospheric Environment
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• v.5 no.2
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• pp.113-120
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• 2011

Adsorbent combination studies have been carried out to remove nitrogen dioxide ($NO_2$) and volatile organic compounds (VOCs: BTEX) out of a subway environment characterized by high flow and low concentration. Optimal conditions for the high removal efficiency of the concerned target compounds were obtained through testing a series of control factors such as adsorbent sorts, thicknesses, and superficial velocity. It was found that the efficiencies increased as the specific surface area of activated carbon and its thickness increased, and external void fraction decreased. Furthermore, mixed activated carbon with granular and constructed contents was extensively tested to reduce pressure drop through the carbon bed. It was found that the performance of higher contents of granular activated carbon was better than that of higher contents of the constructed carbon. When the mixed carbon was applied to the subway ventilation system in order to eliminate $NO_2$ and VOC simultaneously, the removal efficiencies were found to be 75% and 85%, respectively.