Document B88dRro1oO9QeyagjYBqKLyKL

*AS THE MOUNT SINAI MEDICAL CENTER ONE GUSTAVE L LEVY 1*LA(_E * NEW YORK. XY ltnC* Mourn Sinai School ofMcd(Cimr *7he Mount Sinai Hospital August 2, 1983 Ent'ironmental Scimrr* Lsfraior\ Cummings Bosie Seinreu PuUdtng in Cass U)2 Strrrt ,V#r York. (Veer York 10C25* t2J2> Hr. Chuck Scarborough Channel 4* WHBC ... 30 Rockefeller Plaza Hew York, MY * **.*.-**'*. . * .\ -* r/'* ' *' * *..`-**- Dear Hr. Scarborough: *. ' ** . Several weeks ago ve received from your television network three samples of Honokote MK,--5 spray insulation, taken from three differ** ent construction sites in Mew York City* These samples were identi fied as follows: lot 5G2, lot 2D1 and lot SCI. Each sample was prepared for electron microscopic analysis in -. the same manner* An aliquot was first passed through a Mo* 120- mesh screen for. the purpose of separating finer dust from dtraps of material* This fraction was then treated with 0.1 molar sulfuric acid to dissolve the gypsua present** After washing and drying, the material was prepared for electron microscopic analysis by the "wipe-out" technique* At least 20 grid openings, on twelve grids, were scanned at 13,0002 magnification (a total of from 2 to 3 tremolite fibers were seen for each sample) Their iden tities were established by chemical and ultra-structural characteri- ration. These fibers represent only a* "trace of the total mass of the aliquot examined. Vhile -the precise quantity of tremolite present in each sample is difficult to measure, it say he estimated to be on the order of ten-thousandths of a percent, or possibly parts per million, by voltme* .' * t On the basis of this nineralogical characterization, X would consider these three samples of Honokote HR-5 to be virtually free of asbesti-- form mineral fiber. Ve- tru] >urs . Arthur N* Rohl, Ph.D. Assistant Professor, Mineralogy EXHIBIT C