• 한국산업보건학회지
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• 제18권1호
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• pp.20-31
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• 2008

A respirator is useful to protect a worker from the harmful gases and vapors in the workplace, and the evaluation of respirator cartridge service life is important for the worker's health and safety. The performance of cartridge is effected by several factors such as concentration of gas and vapor, humidity, temperature, adsorbents and cartridge packing density. Adsorption model was applied to both sampling tube and respirator cartridge to predict the service life for organic vapors. The variables of the adsorption model were measured from the experiment with the sampling tube, and it was used to predict the service life of respirator cartridge. In the experiment, we used carbon tetrachloride as a organic vapor and activated carbon take out respirator cartridge as activated carbon. As a result, it was possible to predict the service life of respirator cartridge and predicted service life was quite correct. Breakthrough time decreased with increase of CCl4 concentration. In case of sampling tube, adsorbed amount of CCl4 was larger than respirator cartridge due to linear velocity. Also, rate constant of sampling tube was larger than respirator cartridge, because of, effect of flow rate, packing density. In the prediction of service life of respirator cartridge by using sampling tube, the time required for 50% contaminant breakthrough(${\tau}$) is more effective than the rate constant(k').

• 한국안전학회지
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• 제11권4호
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• pp.72-78
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• 1996

The breakthrough curves of a sampling tube were studied to predict the service life of a respirator cartridge for organic vapors. The fixed bed adsorption model was applied to respirator cartridge and it's variables were calculated from tile experiment of sampling tube. By the experiment and simulation, it was possible to predict the service life of a respirator cartridge, however, not adequate at low $CCl_4$ concentration less than 700ppm and at high air humidify. The breakthrough curves of sampling tube were irregular compare to that of respirator cartridge due to .packing density.

• 한국안전학회지
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• 제11권2호
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• pp.89-95
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• 1996

To predict the service life of an organic vapor respirator cartridge, the breakthrough curve of respirator was simulated using a fixed-bed adsorption model and compared with that of sampling tube. And the effects of bed porosity, length to diameter ratio and flow rate of the sampling tube were studied. The life time of respirator cartridge was increased with the decrease of particle size and bed porosity. And the breakthrough time of sampling tube was affected by the flow rate, however not by the length to diameter ratio. The 10% breakthrough time of the sampling tube was corresponded with that of cartridge.

• 한국산업보건학회지
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• 제18권3호
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• pp.204-215
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• 2008

Many researches for service-life of chemical cartridges of respirators have been performed in many countries. On the result of these researches a few softwares programs were eventually developed to be used. In spite of that, it is difficult to apply these researches and softwares practically in the work spot because of too many factors that influence on service-life of chemical cartridges. This study was the first of two conducted for the purpose of developing program for estimating exchange period or service-life of chemical cartridges available feasibly in the workplaces. Collecting plan of cartridges discarded after use is in principle that three cartridges from three workers at a time, three steps of 1/2 exchange time due to smelling, just routine exchange time and 1.2 to 1.3 expanded time of routine exchange, total nine cartridges are collected in the same job site. 33 cartridges for organic vapor were collected in paint spray process of ship yard and paint factory, and 6 cartridges for acid were collected in plating process. These cartridges were analysed the remaining breakthrough time in 3M Innovation Center. Challenge vapor and breakthrough concentration were complied with Korean regulation for chemical cartridge respirators. Estimated breakthrough time was determined from previously used time plus breakthrough time for the remaining. Exchange period of cartridge would be the shortest time among three estimated breakthrough times. On the result breakthrough time for organic vapor was found to be relatively easily estimated, but that for acid aerosol or vapor was difficult to be confident. Even though this method was difficult to be precisely predicted exchange period of cartridge, it could be an alternative program practically available in the job site.

• 생명과학회지
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• 제20권1호
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• pp.60-65
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• 2010

파속류에 다량 함유된 황화합물들은 GC/ECD에 민감하게 반응하기에, 이 농산물들의 잔류농약분석에서 방해 물질로 작용하여 농약성분의 분리정량에 어려움을 주고 있다. 최근 잔류농약분석에서 정제법으로 여러 가지 고상추출법(solid-phase extraction)이 개발되고 있으며, 본 연구에서는 황화합물을 효율적으로 제거하기 위하여, 20% 질산은($AgNO_3$)용액 3 ml을 Florosil cartridge (1 g packing, 6 ml tube)에 처리한 은이온흡착 cartridge (silver nitrate impregnated florosil cartridge)를 조제하였다. 이 cartridge를 이용하여 파속류 각 2, 4, 6 및 10 g에 해당하는 추출액을 고상추출법으로 정제한 결과, 양파 6 g, 대파 4 g, 쪽파는 4 g 까지는 황화합물의 95% 이상을 제거할 수 있었다. 그리고, 40종의 농약을 각 파속류에 첨가하고 이 cartridge에서 유출하여 회수율을 분석한 결과 34종이 70~120%의 범위 안에 들었다.

• 한국산업보건학회지
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• 제19권2호
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• pp.102-112
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• 2009

The greatest concern of vapor/gas respirators is when to exchange chemical cartridges, but it is very difficult to estimate the breakthrough time of them in the workplace spot due to so many factors influencing on breakthrough. There needs to study on estimating cartridge exchange period available practically in the spot, even if it is not precise. In the previous study, authors suggested the method on estimating service-life of chemical cartridges using cartridges discarded after use. This followed study was to estimate exchange period for chemical cartridges using comparison of concentrations between Korean Occupational Exposure Limits (KOELs) and odor thresholds of chemicals. Chemicals were divided into four groups, I, II, III and IV groups. Group I chemicals are relatively safe if cartridges are just or slightly delayed exchanged when smelling since odor thresholds were less than 0.5 times KOELs. Odor threshold of Group II chemicals are 0.5~2.0 times KOELs and potentially hazardous if cartridges are exchanged when smelling. Those chemicals should be conducted program on estimating service-life of cartridges, which was just previously published (J Kor Soc Occup Environ Hyg 2008;18(3) 204-215). Group III chemicals (odor thresholds are more than 2.0 times KOELs) and Group IV chemicals (odorless or no data for smelling) must be performed the above mentioned program before cartridges. Even if this method on cartridge exchange using odor threshold is practically widely used in the workplace spot in the present, program on estimating service-life of cartridges is recommended for all chemicals to reduce potentially hazards.

• 한국환경보건학회지
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• 제37권1호
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• pp.50-56
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• 2011

The adsorption capacity of charcoal is a function of the airborne concentration of the target chemical. To evaluate the adsorption capacity of charcoal packed in the cartridges of air purifying respirators, breakthrough tests were conducted with carbon tetrachloride for three commercial cartridges (3M models #7251, #6000 and AX) at 25, 50, 100, 250 and 500 ppm. Adsorption capacities were calculated using a mass transfer balance equation derived from the curve fitting to the breakthrough curves obtained experimentally. Carbon micropore volumes were estimated by iteration to fit the Dubinin/Radushkevich (D/R) adsorption isotherm. They were 0.6566, 0.5727 and 0.3087 g/cc for #7251, #6000 and the AX cartridge, respectively. Above 100 ppm (at high challenge concentrations), #7251 and #6000 showed higher adsorption capacities. However, as the challenge concentration decreased, the adsorption capacities of #7251 and #6000 sharply dropped. On the other hand, the adsorption capacity of the AX cartridge showed little change with the decrease of the challenge concentration. Thus, the AX showed a higher adsorption capacity than #7251 and #6000 at the 5-50 ppm level. It is concluded that service-life tests of cartridges and adsorption capacity tests of charcoal should be conducted at challenge concentration levels reflecting actual working environmental conditions. Alternatively, it is recommended to use the D/R adsorption isotherm to extrapolate adsorption capacity at low concentration levels from the high concentration levels at which breakthrough tests are conducted, at a minimum of two different concentration levels.

• 한국환경농학회지
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• 제31권1호
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• pp.45-51
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• 2012

본 연구는 단감 재배 중 사용되는 살균제인 pyrimethanil과 trifloxystrobin의 생산단계 잔류허용기준 설정을 통하여 안전한 단감 생산에 기여하고자 수행되었다. 먼저 pyrimethanil과 trifloxystrobin을 살포하고, 살포 후 0, 1, 2, 3, 5, 7, 10, 12, 15, 18일에 단감 시료를 채취하여 각각의 농약을 분석하고 생물학적 반감기를 산출한 다음 생산단계 잔류허용기준(PHRL; Pre-Harvest Residue Limit)을 설정하였다. 단감 중 pyrimethanil과 trifloxystrobin은 Acetonitrile을 이용하여 추출하고 $NH_2$ cartridge와 PSA를 이용하여 정제하여 HPLC/DAD를 이용하여 분석하였다. 두 농약에서 검출한계는 모두 0.01 mg/kg이었다. Pyrimethanil의 회수율은 0.1과 0.5 mg/kg 두 수준에서 각각 $81{\pm}1.62%$, $98{\pm}1.58%$ 이었으며, trifloxystrobin의 회수율은 0.1과 0.5 mg/kg 두 수준에서 각각 $91{\pm}2.94%$, $98{\pm}1.25%$이었다. 단감에서 pyrimethanil의 생물학적 반감기는 기준량 살포 시 15.6일, 배량 살포 시 11.6일이었고, trifloxystrobin의 생물학적 반감기는 기준량 살포 시 10.4일, 배량 살포 시 10.3일이었다. 잔류회귀 감소식을 이용한 생산단계 잔류허용기준은 pyrimethanil과 trifloxystrobin은 각각 수확 10일 전 2.69 mg/kg과 0.83 mg/kg으로 제안하였다.

• 농약과학회지
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• 제17권4호
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• pp.307-313
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• 2013

본 연구는 매실 재배 중 사용되는 살균제인 azoxystrobin과 difenoconazole의 잔류특성을 알아보고 생산단계 잔류허용기준(Pre-Harvest Residue Limit, PHRL) 설정을 통하여 생산단계에서 합리적인 잔류농약 관리기준을 마련하기 위해 수행되었다. 먼저 두 살균제는 안전사용기준 농도로 희석하여 1회 살포와, 동일한 농도로 희석하여 7일 간격 3회 살포 구간으로 나누어 살포 후 0, 1, 2, 4, 6, 8, 10, 12, 14일에 시료를 채취하여 분석에 사용하였다. 매실 중 azoxystrobin과 difenoconazole은 QuEChERS 방법으로 추출하고 $NH_2$ SPE cartridge를 이용하여 정제한 후 HPLC/DAD와 GLC/ECD로 각각 분석하였다. Azoxystrobin과 difenoconazole의 정량분석한계(Method Quantitative Limit, MQL)는 0.03 mg $kg^{-1}$과 0.006 mg $kg^{-1}$으로 나타났다. Azoxystrobin의 회수율은 0.3 및 1.5 mg $kg^{-1}$ 수준에서 각각 $93.2{\pm}2.49%$, $85.5{\pm}1.97%$이었으며, difenoconazole의 회수율은 0.06 및 0.3 mg $kg^{-1}$ 수준에서 각각 $100.8{\pm}6.74%$, $87.6{\pm}9.92%$이었다. 매실에서 생물학적 반감기는 기준량 1회 처리와 기준량 7일 간격 3회 처리에서 azoxystrobin은 각각 5.9일과 5.2일, difenoconazole은 9.3일과 8.0일로 나타났다. 잔류회귀 감소식을 이용하여 생산단계 잔류허용기준을 설정한다면 수확 10일전 azoxystrobin은 5.32 mg $kg^{-1}$, difenoconazole은 1.64 mg $kg^{-1}$ 이하로 잔류할 때 수확 시 잔류농도가 잔류허용기준(Maximum Residue Limit, MRL) 이하로 잔류할 것으로 기대된다.

• 농약과학회지
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• 제19권4호
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• pp.354-360
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• 2015

본 연구는 소면적 재배작물인 산마늘을 대상으로 tebuconazole 및 fludioxonil의 잔류특성을 조사하여 잔류허용기준(MRL) 및 안전사용기준 설정을 위한 자료로 활용하고자 수행하였다. Tebuconazole 20% 액상수화제 및 fludioxonil 20% 액상수화제 농약을 기준량과 배량의 농도로 토양관주처리한 후, 15, 30, 45일차에 시료를 채취하여 분석하였다. 두 약제 모두 dichloromethane을 이용하여 분배하였으며, SPE-Silica cartridge와 SPE-$NH_2$ cartridge를 사용하여 정제한 후, GC/NPD를 이용하여 분석하였다. Tebuconazole과 fludioxonil의 회수율은 각각 108.8~119.5%, 91.3~104.8%였으며, 이 때의 분석검출한계는 모두 $0.01mg\;kg^{-1}$이었다. 산마늘 중 tebuconazole의 잔류량은 <$0.01{\sim}0.12mg\;kg^{-1}$이었으며, fludioxonil의 경우 $0.01{\sim}0.09mg\;kg^{-1}$이었다. 두 약제의 잔류량으로부터 산출한 ADI 대비 식이섭취율(% ADI)은 각각 17.44%, 25.75%로 산마늘 중 tebuconazole 및 fludioxonil에 대한 ADI 대비 식이섭취율(% ADI)은 80%를 초과하지 않으며, 식이를 통한 두 약제의 노출 위험도는 안전한 수준인 것으로 판단된다. 이에 따라 tebuconazole 20% 액상수화제 및 fludioxonil 20% 액상수화제는 산마늘의 병해를 방제하는데 활용할 수 있으며, 잔류농약 문제를 효율적으로 관리할 수 있을 것이라 판단된다.