Document yb4EjoeGD62M43qZOrKpDX8Y6

t August 7, 1951 1ir* r* C. SatarcJ Industrial Relations Division Owene-Ulinois Gists Company Toledo 1, Ohio Dear Bill: Tour letter of July 11 regarding the analyses of dart assies fros the Sayrevilie plant has been received and I an Sorry that an answer hce been delayed so'long. The susaer vac ation period Interferes eoswwhat with eur usual schedule, It would be best if we could sit down and review our report, as you mentica in you.- letter, but perhaps s few coeaets on the questions you ash rill serve as a substitute fcr a personal conference, Percentages on e weight basis. The percentages in all the tables are on a weight basis. Occasionally we may estlr.&te the percentages of the various constituents by ejprtr.g particle oounts, but when the results are reported as per cent by particle count, rather then per cent by weight, a note to that effeet is included in the report* V Competition of aaoelte, Uls the chemist at the Sayrevilie plant we were very much eurprleed to find that the cample of aaetltc . had a quarts content of 21 per cent, it first we thought that eueb a large amount of quarts represented contamination of the sample, but when It was discovered that the ateospberlc dust (sasple 71), collected over a period of 3 hours la the asbestos shredding room, also had a high quarts content, it was obvious that t&^asbestos contained considerable quarts* For analysing these samples we employed both petrographic examination aad the x-ray diffraction method* Although quarts particles ae large as 100 mlerons were seen in the samples when examined with the petrographic mleroeeope, the lines of the x-re/ diffraction pattern were smooth. Indicating that the usual amount of fine quarts particles also were present. v~ . ( | f f \ '' fe ^ C\r?ir: ( *r. t. 0, Sited ' -2- August 7, 1951 The lints would hare been spotty if the sample had contained only large quarts partieles. Since cample* of fibrous eaterial cannot be nixed st easily as granular dusts, the quest!os of poor sanpling arose. To elimi nate this possibility we repeated the x-ray diffraction analysis of the aaosite and of the ataospherie dust (7A), using different portions of the staples* The values obtained for quarts were praetleslly the saae at beforet 20 and 19 per sent, respectively, as eosptred with 21 and 19 per cent given In the repvt* Atrgsoheric dust at router. A reeheek of sanple 5A cocfimi our previously reported finding that the easple contain* aaoaitt. Is nearly every aieroseopie field there are one er sore fibers and in tone there are several fibers. Tie differentiate aaosite fron ehrysotile by the higher index of aaosite and by the ueual oeeurreaee of aaosite as straight rtiff fibers in conparlson with the curved fibers, of ehrysotile. _isbcstcs_ ccr.tcnt of duet in boxcar. Since our estimate of the aaosite and ehrysotile content of the verious stales wae based merely; upon visual exasir.stlcr. ef the naterial under the petro graphic sieroeoope, the values reported are net very precise. For that res son we listed in the table a range of values, such as S-lf and 35-<5 per oent, rather than single value. It is quite possi ble, therefore, that our estl&ated values for the esbestos cocpenestn are too high, be have attempted to supplement the petrographic examination of asbertos samples with x-rsy diffraeticr analysis but have net been very successful is obtaining accurate quantitative values* let only do we lack sesples or pure ast-estos cintrtlt with which to obtain standard patterns, but in addition the lines of the diffraction patterns of the asbestos mineral* are weak is intensity. Possibly ohosUcal analysis, such as used by your rasearch laboratory, is the bect^SMthod for estimating the asbestos content of nixed dust, provided there are only a few ooapooeots of the dust and the coapositlon of each one is known and la different from the oospcsltlea of the other eoaponents* Although our ostlnate of 27-59 per oent for the esbestos contest of the tto&oepherle dust oollected in the boxcar (staple 6A) nay bo high, Z would not expect the true' valno to be as low as 'the 6*10 per cant reported by your laboratory. Thors was sufficient aaosite to register a distinct x-ray diffrsotlon pattern, and free this finding we would expect the aaosite content alone to be greater than 10 per oent* It ie unfortunate that we are w&abla to obtain with the x-ray diffraction method quantitative value* for the asbestos inertia that art as reliable as those for quarts* 0"21G I Mr. T. 0. Sturt *3. lopit T, 191 If the asbestos content of the dust Id tbs boxcar Is only 3*10 per sent la steed of 27*59 per oeat tad the dust count is about 40 to 63 Billion, then the closure of sen loading the cr.r probably should sot be regarded as e definite hatard but rather as only a potential one, Cevertheless, lr Tier of the feet that we are not oertaia just what etr.oapherie eoneeatretios of asbestos fibers is the Halt of safety, it would be well to apply the protective seasurss suggested in the report, including the wearing of a respirator and, if possible, sows wthod of reducing the amount of ataospberlo dust. Best personal regards to you. Sineerely ycurs, IXD:lr Theses V, Purhas Assistant ttrector ' e ( S>0".24V C