• 한국산업보건학회지
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• 제19권3호
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• pp.213-232
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• 2009

This document was prepared to review and summarize the analytical methods for airborne and bulk asbestos. Basic principles, shortcomings and advantages for asbestos analytical instruments using phase contrast microscopy(PCM), polarized light microscopy(PLM), X-ray diffractometer (XRD), transmission electron microscopy(TEM), scanning electron microscopy(SEM) were reviewed. Both PCM and PLM are principal instrument for airborne and bulk asbestos analysis, respectively. If needed, analytical electron microscopy is employed to confirm asbestos identification. PCM is used originally for workplace airborne asbestos fiber and its application has been expanded to measure airborne fiber. Shortcoming of PCM is that it cannot differentiate true asbestos from non asbestos fiber form and its low resolution limit ($0.2{\sim}0.25{\mu}m$). The measurement of airborne asbestos fiber can be performed by EPA's Asbestos Hazard Emergency Response Act (AHERA) method, World Health Organization (WHO) method, International Standard Organization (ISO) 10312 method, Japan's Environmental Asbestos Monitoring method, and Standard method of Indoor Air Quality of Korea. The measurement of airborne asbestos fiber in workplace can be performed by National Institute for Occupational Safety and Health (NIOSH) 7400 method, NIOSH 7402 method, Occupational Safety and Health Administration (OSHA) ID-160 method, UK's Health and Safety Executive(HSE) Methods for the determination of hazardous substances (MDHS) 39/4 method and Korea Occupational Safety and Health Agency (KOSHA) CODE-A-1-2004 method of Korea. To analyze the bulk asbestos, stereo microscope (SM) and PLM is required by EPA -600/R-93/116 method. Most bulk asbestos can be identified by SM and PLM but one limitation of PLM is that it can not see very thin fiber (i.e., < $0.25{\mu}m$). Bulk asbestos analytical methods, including EPA-600/M4-82-020, EPA-600/R-93/116, OSHA ID-191, Laboratory approval program of New York were reviewed. Also, analytical methods for asbestos in soil, dust, water were briefly discussed. Analytical electron microscope, a transmission electron microscope equipped with selected area electron diffraction (SAED) and energy dispersive X-ray analyser(EDXA), has been known to be better to identify asbestiform than scanning electron microscope(SEM). Though there is no standard SEM procedures, SEM is known to be more suitable to analyze long, thin fiber and more cost-effective. Field emission scanning electron microscope (FE-SEM) imaging protocol was developed to identify asbestos fiber. Although many asbestos analytical methods are available, there is no method that can be applied to all type of samples. In order to detect asbestos with confidence, all advantages and disadvantages of each instrument and method for given sample should be considered.

• 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.

• 대한환경공학회지
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• 제37권6호
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• pp.371-379
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• 2015

본 연구에서는 주로 건축자재에 많이 사용된 백석면과 갈석면을 대상으로 산 및 열처리 과정에 따른 두 석면의 특성변화를 살펴보았다. 연구결과, 산처리 과정에 따른 백석면의 굴절률, 신장부호, 소광특성은 대체로 산처리하지 않은 백석면 초기 특성과 유사하게 나타났지만 pH 1.2의 강한 산성용액에서 8주 경과 후, 미지의 입자가 형성되는 등 백석면 고유의 특성이 소실되었다. 산처리 과정에 따른 백석면 구성성분의 중량비(%)는 규소의 경우, 크게 변하진 않았지만, 산소와 마그네슘의 경우, 중량비(%)가 다소 변동하였다. 갈석면의 경우, 굴절률, 신장부호, 소광특성은 pH 및 경과시간과 상관없이 산처리하지 않은 갈석면과 동일하게 나타났으며, 갈석면 구성성분의 중량비(%)는 철의 경우, 산처리 과정에 따라 다소 증가하는 경향을 보였으며, 산소는 이와 반대로 감소하는 경향을 보였고, 규소와 마그네슘은 산처리 전 후 유사하게 나타났다. 열처리 과정에 따른 백석면 굴절률은 온도가 높아질수록 수평방향, 수직방향의 굴절률이 모두 증가하였으며, 신장부호는 $1,100^{\circ}C$에서 10분간 가열했을 때 (+)에서 (-)로 변하였고, 소광특성은 변하지 않았다. 열처리 과정에 따른 백석면 구성성분의 중량비(%)는 규소의 경우, 중량비(%)는 크게 변하진 않았지만, 산소와 마그네슘의 경우, 온도별 열처리 과정에 따라 중량비(%)가 크게 변동하였다. 갈석면의 경우, 굴절률은 온도가 높아질수록 수평방향, 수직방향 모두 증가하는 경향을 보였으며, 열처리 과정에서 신장부호 및 소광특성은 변하지 않았다. 갈석면 구성성분의 중량비(%)는 산소와 철의 경우, 온도별 열처리 과정에 따라 중량비(%)가 크게 변동하였지만, 규소와 마그네슘은 전반적으로 온도 및 가열시간과 상관없이 열처리하지 않은 갈석면과 유사하게 나타났다.