Document 3QKLXLgoEq3p7Lw84bdGdwEOa

MVA'Icc. Excellence in -- Microanalysis PLAINTIFF'S EXHIBIT 1)120,0 20 January 1993 Mr. Robert T. Cheng Chevron Corporation P.O. Box7924 San Francisco, Califomia 94120 PLAINTIFFS EXHIBIT Dear Mr. Cheng, Some time ago l read with interest the 1991 paper you co-authored with Henry McDermott entitled "Exposure to Asbestos from Asbestos Gaskets" which appeared in Applied Occupational Environmental Hygiene, I found it to be very well written and informative. It inspired me to take a close look at some asbestos sheet gaskets to see if asbestos fibers were protruding from the surfaces or whether they were fully encapsulated in the binder. The results were published last year and copies are enclosed. Our work shows that not all the asbestos fibers in the gaskets are bound in the organic matrix and are, therefore, available to be abraded from the surface. It reenforces your conclusion that potential, short term, high exposure can be eliminated by working with the materials in a wet condition as you would with friable material. I noticed that your paper did not include any information about analyses which identified the gaskets as asbestos-containing. Were such analyses done? If you still have the air samples and would like some additional information about the types of fibers present, I would be happy to analyze a few by the NIOSH 7402 (TEM) procedure at no charge, Comparison of PCM and TEM counts of asbestos fibers is of particular interest to me. if you are interested in pursuing this effort please call. Sincerely, JRM/ds -nc&osures aames R. Millette, Ph,D. Executive Director iy.rZC. -rCr -f&L. <Z*f*&* i*rlA- MigTT:CHHNG120 5500 Oak brook Parkway *200 Norrross. Georgia 30093 e / / /C Telephone -J04^^2'5509 Facsimile* 404>662'S532 VW-04744 V ) tl \I a sJ rv-^ ^3T * ^ss 5 ._ >i k C s2 _* Vw f*