Document 1y1xy1DXgmpgarOjYqg37p93X

PLAINTIFF'S EXHIBIT Bell Laboratories 600 Mountain Avenue Murray Hill, New Jersey 07974 Phone(201)582-3000 April 20, 1979 J. J. Preis New York Telephone Company 1095 Avenue of the Americas New York, New York 10036 Dear Jack: The two filter cassettes and bulk insulation sample from the 11th floor of 1166 Avenue of the Americas which you submitted with your letter of April 9th have been analyzed for asbestos. Bulk Sample The insulation sample labelled Mllth Floor Ave of the Americas" when examined by polarized light microscopy and dispersion staining revealed many isotropic fibers' Cprobably mineral wool) but no fibers similar to asbestos. An x-ray diffraction scan of the materials showed the major crystalline phases present were calcite and gypsum. No amphibole or serpentine asbestos was found. Based on these results the sample did not contain any asbestos. Air Filter Cassettes The two air filters were analyzed by counting all fibers greater than 5 urn long seen by phase contrast microscopy at 400x. This is the method recommended by the National Institute of Occupational Safety and Health (NIOSH). Based on your sampling data and the microscopy counts the results were: CONFIDENTIAL 003777 2- Sample #1 11th FI. 1166 Ave. of Amer. Blank Air Volume -Ol 120 -- Fibers Counted* 9 5 Uncorrected Fibers/cnr Blank Corrected Fibers/cm* .06 .03 -- -- 100 microscope fields .011 mm^/field) were counted. The filter area was 855 mm2. If you have any questions about this analysis please give me a call. Sincerely, QfiG Charles P. Lichtenwalner Ref: 1013 Copy to P. H. Stark - NYT C. H. Steinmetz, M R. L. Beach - ATT N. J. DeCapua J. M. Degen ---- " R. W. Stone, M.D. W. J. Schreibeis G. M. Wilkening CONFIDENT/* i 003778