Document dDOg8QvDJ3B87J06kZ4BD2bMG

PLAINTIFFS EXHIBIT QSgfrb.Cfil August ?, 1951 Ur. IT. 0. Easard Industrial 2elation* DiTieicn Cwena-Illinoia das* Company Toledo 1, Ohio Bear Bill* Tour letter of July 11 regarding the analyte* of dust etsslea from the Sayrevills plant ha* been received and I as terry that as answer has been dalayed so long. The turner net* - ties period int*rf*ros..ean*what with our usual schedule. It would be best if ww could sit down sod review our report, as you Bastion in your latter, but perhaps a fer eossaests on the question* you ash will' serve aa a substitute far a pertesal conference. Percentages on a weight basla. The percentages in all the tables are on a weight basis. Gcoeaioaally vre Bay eatinate the percentages of the various constituents by --particle count*, but than the recult* are reported as per cant by particle count, rather than par east by weight, a note to that effect is inoluded in tho report. Cesooffitloa of aBoslta. Like the chemist at tho Sayrsvill* plast we were very such surprised to find that the staple of anoaite had a quarts content of 21 per eest. It first we thought that such a large amount of quarts represented oontan.!nation of the saspls, but when It was discovered that the ataospheric dust ( easple 7Jl), oollooted over a period of 3 hours in the asbestos shredding rooa, also had a high quarts content, it was obvious that tha asterto* contained considerable quarts. For analysing these sespies we ployed both petrographic aranin*ties and the x-ray diffraction method. Although quarts particles as large as 100 sioroos were seen In the staples when eza&ined with the petrographic sleroaeopa, the lines of tha x-ray diffraction patters were asooth,. indicating that the usual aauant of fine quarts particles also were present. PLAINTIFFS EXHIBIT vN-CiCnfe-fe Ip. IT. 0, Hazard -2- August 7, 1951 7b* line* would ham bees spotty if the sample had contained only largo quart* partiQlet. Sine* staplet of fibrous material cannot be sized as easily as granular dusts, the question of poor saapling arose. To elini-- nata this possibility we repoated the x-ray diffraotion analysis of the asoslt* and of the atmospheric dust (71), using different portions of the samples. The values obtained for quarts wen practically the saaa as beforei 20 and 19 per cent, respectively, as compared eith 21 and 19 per cent given in the report. Atootaherlc dust at router. 1 recheek of staple SI confirm our proviously reported finding that tbs staple contains aaosite. In nesrly every aieroseople field there are one or aere fiber: and in sons thoro aro several fibers. He differentiate aaosite from ehrysotile by the high"? index of aaosite and by the uenal occurrence ef aaosite as straight stiff fibers in comparison elth the carved fibers of ehrysotile. Asbestos content of duet in boxcar. Sines oar estisate of the anosite sad ehrysotile content of thaT*various sasples was based zaerely apes visual examination of the aaterlal under the petrographio microscope, the values reported are not very precise. For that roasm we listed in the table s baage of values, such as 5-10 'and 35-45 per east, rather than a single, value. It is quite possi ble, therefore, that our estimated values for the asbestos eospsonts are too high. He have attempted to supplement the petrographic eras*,nation of asbestos aerplas rlth z-ray diffraction analysis but have ant bean very successful in obtaining accurate quantitative values. Sot only do we lack samples of ptire asbestos ulnerals with te obtain standard patterns, but in addition the lines of the diffraction pattens of the asbestos minerals are weak in intensity. Possibly chad cal analysis, such as used by your research laboratory, <! the best Bathed for estlaatiag the asbestos content of nixed dust, provided there ere mly s few components of the dust and the compos! tloB of each eee is Imom aad is different fboa the composition of ' th* other eeapamestts. Although our estisate of 27-59 per ezrt for the asbestos content of the edospherle duct collected in the bozesr (sssple 6A) any be high I would not expect the true value to be as low as the 6-10 per cent reported by your laboratory. Than was sufficient aaosite to register a dietloot x-ray diffraotion pattern, aad from this finding ee would aspect the aaosite content alone te be greater than 10 per cent. It ia unfortunate that we an unable to obtain arlth the z-ray diffraction eethod quantitative values for the asbestos minerals that are as nliable as those for quarts. Mr. 0. Hasard -3- August 7, IS 51 If the asbestos cootoat of the dust In the boxcar la only 6-10 per cant laatead of 27-39 per cent and the dost count la about 43 to 50 Billion, then the closure of esn loading tho car probably abould not be regarded as a definite hazard but rather as only a potential one, nevertheless, la Tier_of the fact .hot ue are not pertain in at what atnoanherio conceotratlonof asbestos fibers 1 the iialt of safety. It arouldbe eell to apply the protective aeaaurea suggested in ine report, Including the uearlag of a re apt rotor _ang. ifposslble, eoxee method of reducing the anount of a'taospherlc dust, ~ Beat personal regards to you. Sincerely ycurs. THSslr Tboaes V, Thrrkas Assistant rireetor