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<br />APR 2 52008 <br />Analytical Procedures - Level II <br />Transmission electron microscopylenergy dispersive X-ray spectrometry/selected area <br />electron diffraction (TEMIEDXISAED) was employed in the analysis of the samples, <br />which were collected on 25 mm mixed cellulose ester air filters. A portion of each alter <br />was collapsed with acetone and etched in a plasma asher. The etched fitter was then <br />coated with a thin layer of carbon in a carbon evaporator. A small pied of each fitter was <br />placed onto a 3 mm diameter copper TEM grid with the carbon side down. The sample <br />was then placed inside a Jaffe wick washer and treated with acetone to remove the fitter <br />matrix and expose any inert material. <br />Ten grid openings on a 200 mesh TEM grid are searched for fibrous structures which, if <br />present are analyzed by SAED and EDX (elemental analysis). Level If protocol requires <br />SAED confirmation of all asbestos identifications. EDX confirmation is also required for <br />the first 5 chrysotile structures, the first 10 amphibole structures, and every tenth structure <br />after the 5 or 10 structure minimum is met. The morphology of each structure is <br />determined and the length and diameter of any asbestos structures is recorded- <br />Asbestos fibers, bundles, clusters, and matrices were identified and recorded. These <br />asbestos structures have been defined in Yamate et al., as follows: <br />Fiber: is a structure having an aspect ratio of 3:1 or greater with <br />substantially parallel sides. <br />Bundle: is a structure composed of three or more fibers in a parallel <br />arrangement, with each fiber closer than the diameter of one fiber. <br />Cluster: is a stucture with fibers in a random arrangement such that all fibers <br />are intermixed and no single fiber is isolated from the group. <br />Matrix: is a fiber or fibers with one end free and the other end embedded or <br />hidden by a particulate. <br />If more than 100 asbestos structures are identified and confirmed on a sample, Level li <br />analysis may be terminated after completion of the grid opening which contains the 100th <br />structure. <br />Equations Used for Calculations <br />Area Anarized, mm' = # GO counted x Average GO Area (mm) It- Concentration s/cc = # Asbestos StructuresX- x cff Filter Area (mmz) v x 1 L <br /># GO Counted VolurrA f . L) Average Area tmm 1(704 i; - <br />niter boading, WM n` . *Asbestos Structures - <br />ea Analyzed (mm ) <br />GO = TEM grid opening