Document R2O8q1Dm7xmNRRQJ3Rk9NZM57

c Jnuirj 20, 1945 Mr. Tr*4 Cook, Manager Safety Engineering Department Bituminous Casualty Corporation Sock la land. Illinois Dear Mr. Cooks Sam Themes has just rtferrod your letter of Janoary IS. 1965 and eoples of your tvo previous letters to me for reply. Pleate seeept uj apology for the delay la response to these coosunlcatloas bat for tone reason neither of your earlier letters reached this department. Zb anaver to your question* the amount of asbestos la KayIn and Kaylo 20 ranges froa 121 to 161 of the total quantity of material la these products, this Is a relatively small amount, particularly la relation to earlier forms of Insulation. As you knar, the per cent of ashes toe fibers la the preformed product ero significant only es it might permit en estimate of the number of a it-boras flbars la the working environment. Air s*aq> lings would provide thle informatloo but such date are most difficult to obtain, particularly under the variety of conditions that o construc tion worker usually operates. However, with respect to asbestoels, Z will mention a few factors that may be of Interest. The American Confarcnce of Governmental Industrial Hygienists publishes ea annuel Threshold Limit Talus for numerous materials. Ibis guide Is widely accepted in the United States. The limit value for asbestos is 5,000,000 particles per cubic foot and Is based upon current knowledge and experience. These values are subject to ehango es new date ere obtained. Z am sure that yon ere familiar with this publica tion so Z will not go into note detail on tho subject. During a recent worldwide symposium om tho tonic meturo ol asbestos, tvo Interesting points wore modes 1. That la tho breed experience of most of tho roportlag doctors smd scientists, neither symptoms nor pathogenesis era usually datoetod prior to 12 years of exposure to asbestos. PLAINTIFF'S EXHIBIT Q00M2>\ 01 027 0192 m ALL-STATE LEGAL Mr. Frtd Cook 2 ' Jsnusry 20, IMS 2. That it la extremely difficult to distinguish between ashes toela and one of tba other palaooiry diseases by radiographic scans a loos. As you know. It la sot uncommon for an a 1 latent or disease to be attributed to a current and known exposure. The Flbergtas Corporation does not produce asbestos, hot purchases It Iron other sources. Actually, the sales of Eaylo produets have been a nlnor portion In the field of high temperature Insulation#. Re doubt some ef the larger producers ere better informed on the cubject then v# ere end perhaps would be better eble to ensver your ^uestlona. Sincerely, FHX:Jt V. B. Edvards Director of Beelth 4 Hygiene 01 027 0193