• 한국관개배수논문집
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• 제16권1호
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• pp.65-71
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• 2009

• 한국산업보건학회지
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• 제19권1호
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• pp.8-15
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• 2009

This study was examined to find out asbestos exposure level the factors which affected the level at asbestos abatement sites. We visited a total of thirteen building demolition sites(3 apartments, 3 schools, 4 stores, and 3 houses) were visited to collect samples and related data from August to November, 2006. The results of this study were as follows 1. The results of an analysis of bulk samples to identify types of asbestos at the asbestos abatement sites showed that the kinds of the asbestos detected were chrysotile by 50.0%, were tremolite by 2.6%, and were the contents of chrysotile by 3 to 20%. 2. The geometric mean concentration of asbestos was 0.007 f/cc(range 0.001-0.34 f/cc) and its geometric standard deviation was 5.83. Of the samples, however, 12 exceeded the Korean Occupational Exposure Limit(0.1f/cc). 3. Of the materials, textile material had the highest concentration with geometric mean of 0.016 f/cc. When asbestos-containing materials were removed using T type tools, the geometric mean concentration of asbestos was 0.061 f/cc. The level by this method was much higher than by other removal methods. In analysis by the type of building, the geometric mean concentration of asbestos in stores was 0.042 f/cc and was higher than in other buildings. 4. The Poisson regression analysis was applied to find out the factors that affect the airborne asbestos concentration. As a result of the analysis, removal using a T type tool was the most important factor affecting the asbestos concentration(p<0.01). In conclusion, the airborne asbestos concentration(geometric mean) in asbestos abatement sites was 0.007 f/cc(0.001~0.34 f/cc), and 12(14.6%) of all samples were over the 0.1 f/cc. These results showed that asbestos abatement workers have been exposed to the high level of airborne asbestos because they have not been keeping asbestos removal rule. In accordance with increases of the number of building demolition sites, the better government regulation on asbestos abatement methods should be made and be performed well at building demolition sites.

• 한국대기환경학회지
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• 제9권3호
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• pp.191-199
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• 1993

This paper describes the results of a systematic study to determine the characteristics of particle generated from various types of asbestos containing material(ACM) and manmade fiber material(MMFM) during operations of cutting and grinding in laboratory and workplace. Tests were conducted with a specially designed glove box which allowed complete sampling of the generated asbestos fibers. Specificially, air measurements were made during ACM and MMFM installation in building. All personal air samples collected were identified by polarized light microscopy(PLM), X-ray diffraction(XRD) and scanning electron microscope with energy dispersive X-ray analysis(SEM/EDXA). Also, the samples were counted by phase contrast microscope(PCM) in order to compare the results with the permissible exposure standard for workplace. Results indicate that the characterisitcs of fibers found in the roofing sheet, the ceiling and the wall insulation boards were identical to those of asbestos, while the characteristics of fibers found in the ceiling insulation board, the floor tile and the sprayed on insulation products in parking area were identical to those of asbestos, while the characteristics of fibers found in the ceiling insulation board, the floor tile and the sprayed on insulation products in parking area were identical to those of rock wool. The concentrations of airborne fibers from various building materials cut by a grinder for 5 minutes were in the ranges of 0.09 $\sim$ 1.71 fibers/cc(f/cc). The highest concentration(1.71f/cc) was found during grinding the wall insulation board which also contains rock wool. The airborne fiber concentrations generated by installing at workplace were ranged from 0.0009 to 0.029 f/cc. All asbestos fibers from the ceiling insulation board at workplace were less than 20$\mu$m in length and more than 20% of them had the average aspect ratio greater than 20. Therefore, for the purpose of decreasing asbestos and man-made fiber concentrations at the workplace, the ceiling and wall board should use strong binding material to increase the binding force with fiber. Also, the permissible exposure standard for workplace(2.0f/cc) in Korea should be constituted below the maximum avaiable concentration measured at glove box.

• 자원환경지질
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• 제52권6호
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• pp.627-635
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• 2019

슬레이트는 석면을 이용한 대표적인 건축자재 중 하나로써 백석면(10~20%)과 시멘트 성분을 결합하여 만든 제품이다. 슬레이트에 포함되어 있는 석면은 인체에 유입되면 세포 손상이나 변형을 일으키고 체외로 잘 배출되지 않아 폐암, 석면폐, 악성중피종 및 흉막비후 등과 같은 질병을 일으키는 원인이 되는 것으로 입증되어 1977년 세계보건기구(WHO) 산하 국제암연구소(IARC)에서는 1군 발암물질로 지정하였다. 현재 이러한 슬레이트는 대부분 지정매립장에 매립하여 처리하고 있으나 매립용량이 한계에 다다르고 있고 매립한다고 하여도 추후 외부환경으로 노출될 수 있는 잠재적인 위험성이 있어 매립 처리방법 이외에 슬레이트에 포함된 석면을 무해화하여 안전하게 처리할 수 있는 방법이 필요하다. 따라서 이 연구에서는 발열반응 촉매제와 열처리를 이용하여 슬레이트에 함유된 석면 무해화 가능성을 확인하고자 하였다. 실험은 석면해체·제거 사업장에서 발생한 석면함유 슬레이트를 이용하였고 발열반응 촉매제는 염화칼슘(CaCl₂), 염화마그네슘(MgCl₂), 수산화나트륨(NaOH), 규산소듐(Na₂SiO₃), 카올린[Al₂Si₂O₅(OH)₄)], 활석[Mg₃Si₄O₁₀(OH)₂]을 이용하여 총 6가지의 촉매제를 제조하였다. 6가지의 촉매제를 슬레이트에 각각 도포한 후 열중량-시차열분석(TG-DTA)을 실시하여 분석결과를 토대로 슬레이트 무해화를 위한 열처리 온도를 750℃로 결정하였다. 슬레이트에 6가지 촉매제를 각각 도포한 후 750℃에서 2시간 열처리하여 X-선 회절 분석(XRD), 주사전자현미경 분석(SEM-EDS), 투과전자현미경 분석(TEM-EDS)을 한 결과 슬레이트 내 백석면[chrysotile, Mg₃Si₂O₅(OH₅)]이 주상의 고토감람석(forsterite, Mg₂SiO₄)으로 상전이 됨을 확인하였다. 또한, 슬레이트 원시료와 발열반응 촉매제 도포 후 열처리한 시료에 물리적인 힘을 가하여 광물의 형상 변화를 비교 관찰한 결과, 슬레이트 내 백석면은 섬유형을 유지하였으나 촉매제 도포 및 열처리를 한 시료는 무정형 형태로 깨지는 것을 확인할 수 있었다. 따라서 발열반응 촉매제와 열처리를 통하여 낮은 온도에서 경제적으로 석면함유 슬레이트를 안전하게 처리할 수 있는 하나의 방안을 제시할 수 있을 것으로 사료된다.

• 한국산업보건학회지
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• 제26권4호
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• pp.454-465
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• 2016

Objectives: The purpose of this study was to evaluate trends in asbestos exposure among asbestos-handling industries from 2000 to 2005. Methods: The data included the number of industries and workers exposed, concentrations of asbestos and the amount exceeded, and the type and size of industry by year. These data were collected by 46 regional employment and labor offices in Korea using work environment monitoring reports. A total of 1,481 samples from 284 industries were extracted from the reports and were analyzed with no data modification. Results: The means of asbestos concentration decreased from $0.84f/cm^3$ to $0.03f/cm^3$ during the period 2000-2005. Among the total of 1,481 samples, 11 samples(0.7%) exceeded the KOEL, and 178 samples(12.0%) were ACGIH TLV. The insulating paper product manufacturing industry was found to have the highest level of asbestos, followed by the fireproofing manufacturing industry, brake lining products manufacturing industry, commutator products manufacturing industries, and construction materials manufacturing industry. The number of asbestos handling industries decreased from 48 industries with 1,155 employees to 37 industries during the period of 2000 to 2005, but the number of asbestos workers expanded to the point that 1,182 employees could be found in 2005. Conclusion: Based on these results, the strengthening of the KOEL and new regulations turned out to help reduce asbestos exposure levels. This study recommends that retrospective exposure to asbestos based on various industry types should be assessed.

• 한국산업보건학회지
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• 제25권2호
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• pp.184-193
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• 2015

Objectives: This study focused on three aspects: characterizing concentrations of airborne particles by size distributions and asbestos fibers generated by various building materials; analyzing the characteristics of fibers produced by each simulation and asbestos fibers released from ACBMs; and investigating correlations of airborne asbestos fibers and particles generated and association of particle and asbestos concentrations. Methods: We selected three ACBMs including an insulation board, cement asbestos slate and wallboard. We constructed 4 scenarios; a) crushing with a hammer; b) cutting with a industrial knife; c) brushing with a metal brush; and d) tightening & loosening with a hand drill. We implemented one simulation for 30 seconds followed by 30 seconds resting period. We repeated a total of 5 cycles for 5 minutes. Results: The highest concentration of particulate & fibrous matters was from crushing with a hammer in each scenario followed by brushing with a metal brush, cutting with a industrial knife, and tightening & loosening with a hand drill. For ACBMs studied, asbestos concentrations were highest from an insulation board followed by cement asbestos slate, and wallboard. No difference in terms of concentration was found between an insulation board and asbestos slate. Fibers with $5{\sim}20{\mu}m$ in length were included in 76~90% of total fibrous matters. The distribution of the straight form fibers was greater than that of the curl form. About 90% of $PM_{Total}$ released from ACBMs was consisted of $PM_{10}$ while only 10% of $PM_{Total}$ was $PM_{2.5}$. Particulate matters like $PM_{2.5}$ was significantly correlated with fibrous matters($R^2=0.81$). Conclusions: We found ACBMs can significantly release asbestos fibers as well as $PM_{2.5}$. Concentrations of asbestos generated by ACBMs were well correlated with $PM_{2.5}$.

• 한국산업보건학회지
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• 제21권3호
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• pp.139-145
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• 2011

Objectives: This investigation is purposed to evaluate the airborne asbestos concentrations in the public buildings having asbestos containing materials(ACMs) in Seoul. Methods: The Seoul Metropolitan Government carried out an asbestos survey to the city-owned public buildings to identify the level of risk exposure, classified into low, moderate and high risk. To evaluate the airborne concentration of asbestos, 11 sampling sites in ten buildings based on the survey were selected. The air samples from the eleven sites were analyzed by Phase Contrast Microscopy(PCM) and Transmission Electron Microscopy (TEM), and compared the analytical results from the both. Results: 1. The airborne fiber concentrations by PCM were less than the detection limit($7f/mm^2$) in 9(82%) out of 11 sampling sites. The highest concentration was 0.0043 f/cc, but it was below the guideline value for indoor air quality(0.01 f/cc), proposed by the Ministry of Environment, Korea. 2. In two sampling sites, having moderate risk level, the chrysotile was identified and showed it's concentrations of 0.0102 s/cc and 0.0058 s/cc, less than $5{\mu}m$ lengths. 3. The ACMs identified in the two sampling sites were a packing material(65% of chrysotile) in mechanical area and a thermal system insulation(5% of chrysotile) in a boiler room. Having more possibility of asbestos emission in the mechanical area, it would be required to set up and carry out the asbestos management plan. Conclusions: Based on the result of this study, the airborne asbestos concentrations in the public buildings with ACMs were generally lower than the guideline value for indoor air quality. There are widespread concerns about the possible health risk resulting from the presence of airborne asbestos fibers in the public buildings. Most of the previous studies about airborne asbestos analysis in Korea were performed based on PCM method that asbestos and non-asbestos fibers are counted together. In the public and commercial buildings, having ACMs, it is suggested that the asbestos be analyzed by TEM method to identify asbestos due to concerns about asbestos exposure to workers and unspecified people.

• 분석과학
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• 제27권3호
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• pp.153-160
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• 2014

세계적으로 석면분석방법에 관한 다양한 연구사례가 발표되고 있는 가운데, 분석방법의 차이에 따른 석면함유물질(ACM, Asbestos Containing Material) 결과에 대한 관심이 대두되고 있다. 본 연구에서는 균질성이 확보된 ACM 시료를 시야평가법(visual estimation method)과 포인트계수법(point counting method)의 분석결과에 대한 비교 평가를 통하여 분석기관 및 분석자의 신뢰성 향상과 더불어 편광현미경 분석의 기초자료를 확보고자 하였다. 석면분석은 정성분석과 정량분석으로 구분하였으며, 석면정량을 위한 방법은 EPA 600-R-93-116의 시야평가법과 포인트계수법으로 총 400지점을 계수하는 방법으로 실시하였다. 먼저 준비된 시료의 균질성을 분산분석을 이용하여 확인한 결과 이상이 없음을 확인하였다. 정성분석의 결과는 백석면과 갈석면으로 확인되었고 정량분석결과는 포인트계수법이 시야평가법과 비교하여 전체적인 석면함유량이 저평가되는 경향과 함께 포인트계수법은 분석과정이 조금 복잡하고 분석시간이 많이 소요되었다.

• 한국산학기술학회논문지
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• 제16권7호
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• pp.5029-5037
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• 2015

본 연구의 목적인 우리나라 일부 학교의 석면함유 건축자재을 조사하고 EPA AHERA rule과 ASTM rule을 적용하여 위해성평가를 실시하였다. 총 100개 학교를 2010년 1월부터 12월까지 조사하였다. 건축년도에 따른 ACM 검출율은 1980년대 이전 건축물은 100%, 1990년대 이전은 94.1%, 2000년대 이전은 100%, 2000대 이후는 62.5%로 나타났다. 학교별 ACM 검출율은 유치원과 고등학교는 100%, 초등학교는 97.1%, 중학교는 92.9%, 특수학교는 80%로 나타났다. 천장 텍스는 2~8 %의 백석면과 갈석면, 밤라이트 보드는 6~11 %의 백석면이 검출되었다. 또한 개스킷과 슬레이트 지붕은 각각 16~17 %, 10~13 %의 백석면이 검출되었다. EPA AHERA rule을 이용하여 ACM의 위해성 평가를 실시한 결과, 모든 건축자재는 "Pool" 등급이 나왔으며, ASTM rule 평가에서는 모든 ACM이 "Q&M program"이 필요한 것으로 나타났다.

• Elastomers and Composites
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• 제36권1호
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• pp.3-13
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• 2001

마찰재로써 석면사용에 따른 환경문제를 해결하고, 폐타이어의 고부가 가치화를 위하여, 폐타이어분말과 육티탄산칼륨을 주원료로 하고, 여기에 충전제, 마찰안정제 등을 혼입, 가공하여 고무가 연속상인 새로운 형태의 마찰재를 제조하였다. 이 마찰재들에 대한 마찰.마모시험결과에 의하면 육티탄산칼륨, 페놀, 마찰안정제, 황산바륨을 각각 5, 20, 10, 20 phr로 첨가시킨 마찰재가 브레이크로 사용하기에 적합한 마찰특성, 즉 높고 안정된 마찰계수와 낮은 마모율을 보여주었다.