• Environmental Analysis Health and Toxicology
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• v.17 no.2
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• pp.117-123
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• 2002

A gas chromatographic method for the determination of airborne formaldehyde was established. In order to be highly detectable with the electron capture detector, formaldehyde was derivatized to its pentafluorobenzyl oxime form by reacting with O- (2,3,4,5,6- pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) at pH of 4.6 and temperature of 50$^{\circ}C$ for 1 hour. Air samples were collected into a Tedlar$\^$(R)/ bag followed by transferring into water contained in two impingers in series. Collection efficiency in the front trap was higher than 90％. Measurement of selected indoor and outdoor air samples showed higher formaldehyde concentrations in indoor air environments and the importance of ventilation for reducing indoor pollution.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.4
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• pp.317-326
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• 2000

Carbonyl compounds have been measured in downtown Seoul for September 1998 using 2-series impinger method. Average concentration (ppbv) of carbonyl compounds were 12.66$\pm$5.77 HCHO, 12.05$\pm$4.86 CH3CHO and 7.92$\pm$2.63 CH3CHCH3 These compounds were the most abundant carbonyl,. They showed maximum concentration during the daytime when photochemical activity was very strong minimum concentration were usually showed during the night and early morning. Comparison of diurnal variation of carbonyl compounds with the concentration of O3, NMHC, CO and meteorological data indicated that primary and secondary sources contributed the observed carbonyl compounds. Photochemical Formation Rate(PFR) of carbonyl compounds dur-ing the sampling periods were 61% HCHO, 85% CH3CHO, 85% CH3CHO, 71% CH3COCH3.

• Journal of Environmental Health Sciences
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• v.34 no.2
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• pp.148-152
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• 2008

Coated filters were developed to replace the glass impinger methods that use reagent solutions. The purpose of this study was to simultaneously measure nitrogen dioxide ($NO_2$) and respirable suspended particles (RSP) by a filtration method with a cyclone connected to a pump. A first pre-filter for RSP and second filter for $NO_2$, which was soaked in a TEA (Triethanolamine) solution, were loaded into a filter cassette with a pump flow rate of 1.7 l/m. After sampling, the TEA soaked filter was removed from the cassette, placed in a large test tube (10 ml), mixed, and allowed time to develop. The absorbance (abs) of the diazo compound of the $NO_2$ and N-(1-Napthylethylenediamine dihydrochloride) in the color reagent was measured at 545 nm on a spectrophotometer. The collection efficiency(%) of $NO_2$ by each 3 filter soaked in TEA solution and used in the cyclone with a pump flow rate 1.7 l/m was $89{\pm}3%$ and the correlation coefficient between the true $NO_2$ concentration and that determined by the TEA soaked filters was 0.993(p<0.001).

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.30 no.2
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• pp.134-152
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• 2020

Objectives: The objective of this study was to evaluate volatile organic compounds (VOCs) and toluene diisocyanates (TDIs) exposure among polyurethane waterproofing workers in the construction industry. Methods: Task-based personal air samplings were carried out at seven construction sites using organic vapor monitor for VOCs (n=88) and glass fiber filters coated with 1-(2-pyridyl)piperazine(1-2PP) for TDIs (n=81). The concentration of VOCs and TDIs were shown for four different work types(mixing paint, primer roller painting, urethane resin spread painting, painter assistant) at five different worksites (rooftop, ground parking lot, piloti, bathroom, and swimming pool). The two TDI sampling methods (filter vs impinger) were evaluated in parallel to compare the concentrations. Results: The geometric mean(GM) concentration of VOCs Exposure Index (EI) was highest for primer roller painting (1.4), followed in order by, urethane resin spread painting (0.85), mixing paint (0.53), and painter assistant (0.35) by work types. The GM of VOCs EI was highest for bathroom (1.4) followed in order by, swimming pool (0.85), piloti (0.89), ground parking lot (0.82) and rooftop (0.57) by worksites. The GM of 2,4-/2,6-TDI concentration was 0.052 ppb and 0.432 ppb each. There was no statistical difference in TDIs concentrations among worksites. The concentration of 2,6-TDI was ten times higher than that of 2,4-TDI. The concentration of 2,6-TDI by impinger method was 5.7 times higher than that by filter method. Conclusions: In this study, we found 38.6% of the VOCs samples exceeded the occupational exposure limits and 19.8% of the 2,6-TDI samples exceeded 1 ppb among polyurethane waterproofing workers. The most important determinants that increase the concentration of VOCs and TDIs was indoor environment and primer painting work.

• Journal of the Korean Society of Tobacco Science
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• v.26 no.2 s.52
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• pp.179-185
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• 2004

This study was conducted to investigate the delivery pattern of volatile organic compounds(VOCs) in mainstream smoke generated by the combustion of a different ventilated cigarette. To compare the delivery pattern and the concentration of VOCs in mainstream smoke, the six different ventilated cigarette was manufactured and analyzed VOCs using the GC/MS. As a result of this experiments, cambridge filter used to trap the particulate matter in mainstream smoke did not affect on the trapping of VOCs components, and two impinger method among the trapping methods was the best condition to trap VOCs from mainstream smoke. As the slope of the delivery of VOCs such as isoprene, acrylonitrile and toluene were higher than 1, but that of benzene was lower than other VOCs.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.6
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• pp.593-603
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• 2005

Passive sampler using 4-amino-3-hydrazino-5-mercapto-1, 2, 4-triazole (AHMT) was developed to determine formaldehyde in indoor environment. The chromatography paper cleaned by $3\%$ hydrogen peroxide solution was experimently determined as a optimum absorbtion filter for the collection of formaldehyde. The passive sampler with a broad cross-sectional area and a short diffusion length was quite good in sensitivity. The passive sampler and the active sampling method with an impinger were strongly correlated with a correlation coefficient of 0.9848. The limits of detection and quantification of the passive sampler for the measurement of formaldehyde in the indoor environment were 7.5 and 10.2 ppb, respectively. Temperature ($19\∼28^{circ}C$) and relative humidity ($30\∼90\%$) had slight influence on the sampling rate of the passive sampler. However, the increase of flow velocity on the surface of sampler resulted in the increase of sampling rate.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.6
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• pp.512-522
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• 2009

In this study, the removal efficiency of trimethylamine (TMA) and four reduced sulfur compounds (RSC) of $H_2S$, $CH_3SH$, DMS, and DMDS was investigated using deionized water as absorbent. To this end, two types of experiments were conducted which include: (1) by passing both RSC and TMA standard gases through water contained in an impinger system and (2) by passing TMA gases through a water spray system. In the former method, TMA standard gases were effectively removed (below detection limit) in all experiments. Likewise, minor fractions of some RSC ($CH_3SH$, DMS, and DMDS) were removed by water in line with theoretical expectations. In addition, the first type of our experiment was extended further to test some commercially available odor treatment products. The results of this test showed that removal efficiencies of RSC $(8.2\pm13.7\sim43.7\pm2.48%)$ were different significantly among 4 kinds of absorbent, while the removal of TMA was consistently good as water. In the second phase of experiment, removal efficiency of TMA was tested by passing its standard gas through a water spray system. The overall results of our study showed that the actual removal efficiency of odorants by water (as sorptive media) approached the values that can be predicted theoretically (by Henry's law).

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.6
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• pp.757-772
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• 2013

In this study, a combination of sorbent tube (ST)-thermal desorption (TD)-gas chromatography (GC)-mass spectrometry (MS) was used for quantitative analysis of liquid phase standards of 10 BVOC ((1) (+)-${\alpha}$-pinene, (2) (+)-${\beta}$-pinene, (3) ${\alpha}$-phellandrene, (4) (+)-3-carene, (5) ${\alpha}$-terpinene, (6) p-cymene, (7) (R)-(+)-limonene, (8) ${\gamma}$- terpinene, (9) myrcene, and (10) camphene). The results of BVOC calibration yielded comparatively stable pattern with response factor (RF) of 23,560~50,363 and coefficient of determination ($R^2$) of 0.9911~0.9973. The method detection limit (MDL) of BVOC was estimated at 0.03~0.06 ng with the reproducibility of 1.30~5.13% (in terms of relative standard error (RSE)). Emissions of BVOC were measured from four types of fruit samples ((1) tangerine (TO), (2) tangerine peel (TX), (3) strawberry (SO), and (4) sepals of strawberry (SX)). The sum of BVOC flux (${\sum}flux$ (BVOC) in ng/hr/g) for each sample was seen on the descending order of (1) TX=291,614, (2) TO=2,190, (3) SO=1,414, and (4) SX=2,093. If the results are compared between the individual components, the highest flux was seen from (R)-(+)-limonene (265,395 ng/hr/g) from TX sample.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.5
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• pp.651-658
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• 2018

Particulate matter (PM) emitted from fossil fuel-combustion facilities can be classified as either filterable or condensable PM. The U.S. Environmental Protection Agency (EPA) defined condensable PM as material that is in the phase of vapor at the stack temperature of the sampling location which condenses, reacts upon cooling and dilution in the ambient air to form solid or liquid in a few second after the discharge from the stack. Condensable PM passed through the filter media and it is typically ignored. But condensable PM was defined as a component of primary PM. This study investigates the change of condensable PM according to the variation in the sulfur dioxide of combustion gas. Domestic oil boilers were used as the source of emission ($SO_2$) and the level of $SO_2$ concentration (0, 50, 80, and 120 ppm) was adjusted by diluting general light oil and marine gas oil (MGO) that contains sulfur less than 0.5%. Condensable PM was measured as 2.72, 6.10, 8.38, and $13.34mg/m^3$ when $SO_2$ concentration in combustion gas were 0, 50, 80, and 120 ppm respectively. The condensable PM tended to increase as the concentration of $SO_2$ increased. Some of the gaseous air pollutants emitted from the stack should be considered precursors of condensable PM. The gas phase pollutants which converted into condensable PM should reduced for condensable PM control.