• Journal of odor and indoor environment
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• v.17 no.4
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• pp.337-345
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• 2018

In this study, we measured the concentration of Particulate Matter($PM_{10}$), Formaldehyde(HCHO), and Total Bacteria Count (TBC) at two facilities: day care centers, and postnatal care centers located in the cities of Gyeonggi, Gangwon, Jeolla and Gyeongsang from January 1, 2012 to December 31, 2015. $PM_{10}$ concentration was similar to the day care centers and postnatal care centers. HCHO concentration was the highest in the postnatal care centers. TBC concentration was the highest in the day care centers. Comparing the different cities, $PM_{10}$ concentration was the highest in Gyeonggi, HCHO concentration was the highest in Gyeonggi, and TBC concentration was the highest in Gyeonggi. As a result of HCHO's risk assessment, it was found that adults exceeded the carcinogenicity tolerance of $10^{-6}$ specified by the US EPA. This study is expected to be helpful in preventing damage to health from the contaminated indoor air at sensitive facilities, and can be used as basic data for indoor air quality management.

• Analytical Science and Technology
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• v.19 no.6
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• pp.544-552
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• 2006

Emission tests were carried out to investigate the characteristics of concentration according to flooring sort using small chamber method. The target Volatile Organic Compounds (VOC) included 27 individual compounds of environmental concern, which were determined by adsorption sampling and thermal desorption coupled with GC/MS method and by DNPH cartridge/HPLC method. The emission factor of Total Volatile Organic Compounds (TVOC) and Formaldehyde (HCHO) was detected $0.3mg/m^2{\cdot}h$ and $0.2mg/m^2{\cdot}h$ respectively, and the floorings of 37 (9 PVC Tile, 10 PVC Sheet, 18 Flooring) were satisfied emission standard. TVOC emission factor appeared in order of concentration of PVC Sheet, PVC Tile, and floor flooring, while HCHO was detected very high emission factor (as $0.4mg/m^2{\cdot}h$) at floor flooring above PVC series (as $0.001mg/m^2{\cdot}h$).

• Journal of the Korean Wood Science and Technology
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• v.45 no.5
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• pp.580-587
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• 2017

Woodfiber insulation board can be considered as a one of the key material for low energy consumption, comfortable and safety construction of residential space because of its eco-friendly and high thermal insulation performance. This study was carried out to investigate the formaldehyde (HCHO) total volatile organic compounds (TVOC) emission properties and combustion shapes by flame test of low density fiberboards (LDFs) prepared with different adhesives. HCHO TVOC emission and combustion properties of LDFs prepared by melamine urea formaldehyde (MUF), phenol formaldehyde (PF), emulsified methylene diphenyl diisocyanate (eMDI) and latex resin adhesives were measured by desiccator method, 20 L chamber method, and flame test, respectively. As results, LDFs manufactured by MUF, eMDI and latex resin adhesives satisfied the Super $E_0$ grade of HCHO emission performance except PF resin. Furthermore, TVOC emission of all LDFs were satisfied the Korean indoor air quality standard (below $400{\mu}g/m^2{\cdot}h$). Especially, LDF with eMDI resin adhesive showed the lowest HCHO and TVOC emissivity, that $0.14mg/{\ell}$, $12{\mu}g/m^2{\cdot}h$, respectively. However, eMDI emitted the small amount ($3{\mu}g/m^2{\cdot}h$) of toluene in VOC components. In the flame test, LDF with MUF resin adhesives showed the most favorable shape after flame test compare to LDFs prepared other adhesives. Based on HCHO and TVOC emission, and combustion shapes, MUF resin adhesive may be recommended to prepare LDF for insulation purpose.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.542-545
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• 2006

In the domestic atmosphere environment, the VOCs and the NOx have a large proportion of the pollutant, and the HCHO is the main environmental pollutant factor within the house. In this study, the inorganic paint which can absorb and remove VOCs, NOx and HCHO is developed by using day-titania carrier. The basic data to develope eco-friendly inorganic paint is collected with the performance test to remove the VOCs, NOx and HCHO in the condition of the addition of several inorganic materials to the paint, and also the plan to practical use of eco-friendly inorganic paint is studied.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.655-658
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• 2005

In the domestic atmosphere environment, the VOCs and the NOx have a large proportion of the pollutant, and the HCHO is the main environmental pollutant factor within the house. In this study, the inorganic paint which can absorb and remove VOCs, NOx and HCHO is developed by using clay-titania carrier. The basic data to develope eco-friendly inorganic paint is collected with the performance test to remove the VOCs, NOx and HCHO in the condition of the addition of several inorganic materials to the paint, and also the plan to practical use of eco-friendly inorganic paint is studied.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.223-224
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• 2002

This study is motivated by the discrepancies found in previous studies that compared the observed photochemically reactive species in the marine boundary layer (MBL) with the model simulations. In particular, HCHO was underpredicted in PEM-Tropics (B) and overpredicted in TRACE-A, $H_2O$$_2$ overpredicted, $CH_3$OOH overpredicted, and $CH_3$OH significantly overpredicted (Thompson et al., 1993; Heikes et at., 1996; Davis et al., 1996; Jacob et al., 1996; Schultz et al., 1997; Suhre et al., 1998). (omitted)

• Korean Journal of Remote Sensing
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• v.39 no.5_1
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• pp.563-576
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• 2023

In this study nitrogen dioxide (NO₂), formaldehyde (HCHO) from the Ozone Monitoring Instrument (OMI) and TROPOspheric Monitoring Instrument (TROPOMI), OMI/ Microwave Limb Sounder (MLS) tropospheric column ozone (TCO), and Airkorea ground-based O₃ data were analyzed to examine the photochemical reaction relationship between tropospheric ozone and its precursors nitrogen oxides (NOx) and volatile organic compounds (VOCs). As a result of analyzing the trend of long-term changes from 2006 to 2020 using OMI satellite data, TCO showed an increasing trend, NO₂ steadily decreased, and HCHO continued to increase in Northeast Asia. In addition, formaldehyde nitrogen dioxide ratio (FNR; HCHO/NO₂ ratio), an indicator of ozone sensitivity, is gradually increasing, which means that the VOC-limited regime is decreasing. This study conducted a sensitivity analysis of ozone generation using TROPOMI FNR and ground-based ozone (O₃) over the recent years (2019~2022) to identify the possible cause for the continuous increase of ozone in Korea. Similar to the previous studies, VOC-limited and transitional regimes appeared in megacities, and VOC-limited regimes also appeared in areas where major power plants were located. In VOC-limited regimes, in other words, areas where NOx is excessively saturated, the reduction in NOx emissions may have weakened the ozone titration and thus led to the increase of ozone. Therefore, VOC emissions should be reduced in the short term rather than NOx emissions to reduce ozone concentrations under the VOC-limited regime.

• 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.

• Korean Journal of Remote Sensing
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• v.39 no.5_1
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• pp.551-561
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• 2023

In this study, we investigated the effects of the spectral fitting window and absorption cross-section on the retrieval of the formaldehyde (HCHO) slant column density (SCD) from the direct-sun measurement of pandora spectrometer system using differential optical absorption spectroscopy (DOAS). Pandora Level 1 data observed at Yonsei University in Seoul from October 12 to 31, 2022 were used. The HCHO column density was retrieved under eight ranges including the spectral fitting window used in the Second Cabauw Intercomparison campaign for Nitrogen Dioxide measuring Instruments (CINDI-2) and seven types of absorption cross-section composition. The spectral fitting window was selected from 336.5 to 359.0 nm with minimum residual and HCHO SCD error. When the nitrogen dioxide (NO2) absorption cross-section at 220 K was added to the cross-section composition used in the CINDI-2 campaign among seven types, the residual and HCHO SCD error were the smallest and the HCHO column density wasstably retrieved. The average HCHO SCD with the highest retrieval accuracy and the values retrieved under other conditions differed from a minimum of 4% to a maximum of 40%.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2008.10a
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• pp.339-340
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• 2008