Document 3eQpBJER8v3yvXYm5azVN1kEx

File Name Brake Lining Wear Dust: 1963 - 1973 Scanned ? yes Source JMA: SI310; S1159; 4-1162; Start Year 1963 Stop Year 1973 Contents report Notes Research & Development Center May 22, 1973 BRAKE AND CLUTCH EMISSIONS GENERATED DURING VEHICLE OPERATION Michael G. Jacko, Eendix; Robert T. DuCharme, Bend!::? and Joseph II. Somers, EPA (Presented at the 1973 5AE National Automobile Engineering Meeting, Detroit, May 16# 1973). SUMMARY by J. W, AxeIson Emission collectors were installed on the right front disc brake and the right rear drum brake and on the dry clutch assembly. The left brakes were left in their normal configuration and were used to monitor the operation of the shrouded brakes. Three types of samples were collected and analyzed for asbestos. These wore the airborne collected on 8.0 u and 0.2 u filters; the surup material; and the debris on the brake surfaces. Optical microscopy with phase contrast at 400X and transmission electron microscopy at 23,00QX weie used to .identify and measure the amounts of asbestos. Tho overall average of asbestos content in brake-emission was 0.23 pt:rr cent from all three sourcos in throe different tests. Some fibers were longer than 20 u. Only 3.7 per cent of the asbestos emission was airborne for the tost vehicle and only 2.9 per cent is estimated for trucks. It was estimated that 51,500 tons of asbestos arc used in friction materials annually and about 37,000 tons arc actually worn away. Knowing the asbevtos emission in ugms per miio it is oosriblc to calculate the total annual ar-b^nto:? emission per year. This comes to a total of 153,200 pounds (79.1 tons) but only 3.2 per cent or ',0 6 0 pounds (2.5 3 tons) in airborne. O/cr 99.7 per cent of the total asbestoci wear is converted to olivine or fomterite. Note Extrapolating '.he Tore! data of only h.0023 per cent of J ining wear appearing as onb ..::tcu fiber, the lotal friction wear optima tod by Bendix of G 1,8 C 0 i- on'? wou 1 cl giye an ? rjh<" tor; cm Lcsrjion of 1.>\ 2 tons (28^0 yeimdu) wbl'*h is a little more than one half of the Bcndix value. This in not bad agreement cot n.i d'o:i?K* the wide dif fe.rences in boat proccdir.-f r. and typ'- of calculations. iiesearch anu lag Csnter Decaaoer 30, !>c6 3. Koch Brake Deeccposities Products ?jiUa Health Service During i rflc^nc .touting cn acbeetcs tad health at tne ?Mbile Health service, I isuraed :has tho *iblie J^eith Service had performed brake vear evyoics i/ .it1dialog ly7US5a&eter equiusuat at the Attericaa Bra a* .hoe CoKseay in .'.avail* '3jw Jersey* Thsco itta verc reported ca .-.orii *, Lvo-j, to -.he assistant to the Chief for ^oidettlolofflr nod ?isld Studies, L'-porTOnt of -Iwaltn by Jarenisa lyneu, bunicr Sanitary lagineer, Jagineering : setics, AwsG&rca r.nd "schaicul services Brunch. briefly? ;oe results thevae ^statically so riser in the deccnpceitico nrcauct at test turner*; cures ;jp to r>tproxiitely !4CO-5CC?. buicplts evaluation wes by electron .hen the test testeraturu ^.yproxiaated 7*OF in ac-cnlloa panic stc^s,. cuu cr/eric^ui condition i pr^-rantly deteriorated the renin bead acrr.i'tihg fib:*r to be ripped out of t.*e Praia inato-nd of o*in& worn off. .-.ppruidssitsiy IS per cent of tsa fiber *?& /:,aoi3 in :hia uscanrositicn i^vsri.nl. Che results ,1*3 sumaariued below* ^yr>e of Brake ,,iic brv Jus braua .-uto .-.utc brake . utc bra/.* ..utc dutC bus brake *.uto brake Auto brake Bus brake Tsst Condition ncnl city iirivin;' nonaai city driving lJ0-00F 300-500? cCO-TCC? 30rail city driving apO-5JCF 100-6GGF 100-300P U50-55CP r \.*nt THb^r 20 1 t.:.* n :* j its' l/ ) ,...0 (fev fibers) 0 0 it d* loch December 30, 1JS6 .it Lynch believe* that the result* clearly indicate that ve&r of brrl-.c linings is net 3 significant factor In contributing fiber to the nt^csphere, lie intend* to publish hi* data a* a brief note very enortly* I have invited hia to visit the Research Center to review our result* /i ;h you *r.d iw/e Indicated that we would give bin pewdssica to '-ur figure*. I b*ii<jv* that publication under the auspices c? *. v-verutcnc Lahore-very would be far acre beneficial than by Johns-4*rilie. I notify ycu t seen as a flm date has been established for thi# visit* ?. l^iasvecoT General Headauarters Aoril 21, 1967 F. L. Pundsack - Pinderne Brake Lining Wear Dust Your Letter of 3/14 to F. J. Solon Your File 253 Confinning our phone conversation of this corning, I aoorove your recommendation that we collaborate with the U. S. Public Health Service through the release of information from this study. The oublication of our data under their auspices will certainly carry considerable weight. It was certainly of consicerable interest, in a recent discussion with Dr. L. J. Cralley, to learn that their findings narallel ours very closely. The ohotograohs which you reouested be returned are attached. enc C C P. J. Solon H. M. Jackson VJO U Research & Engineering Center March 27, 19^8 T V Solon - H. M. Jackson - X, V. Lindell - P. L. Fundsack H. G. Koch J. Leineveber DH DHt- Asb Brake Lining Decoouosition I thought you would like to have a copy of Jerry Lynch's draft of a paper on brake lining deccapositicn vhich is to be subaitted for pub lication in the Journal of Air Pollution Control Association. SS/rs S. 5peil \0 V W L' iprii P, i960 Mr. J. a, Lyncb, Assistant CMef iltrircnrantrl .`ctivifci .a, ri*Vi Studies Zzy-rzwnt of -'dnc-tica 1 Welfare .r*cno*.n >* in ^ Thn.-f; -'r.t ver nii:n for 3 writs,* j-i n draft cC 'cv.r ;iw r or. brf: 1 ' " *a daojwrov ti on vdtyr 7s ach*c X >d fer pohlient.on ;..** Journc; of .*. izt c 1 *," f^O'` sn, . s M% 2r< m *nri ~~, . '** ,,> oni> '.rx..1: .* -mvh;.- v-.v! /. cr.t eclat- i vci..; rn...:*? ',w v-jr* lairt yv . *.; ir. *>.;:,>r. .'.:.* ; 1 : ,:c u vi * r`o *! n ; ir *, s rvtr. ;. r.s '. f ;v i'r * f '. I-j r .*.: \ 1 z: . *... . ^ ***?-, -fifty r-Tprss:nt ' vwy sr:.-*_l presort:, or; Wwl .c:.`.-stc-y .*> * *..: .sanai iCturs cf bribes, ^'id -in. npparanMv on-.:>v . v.-*.*. *' L\ irr;A.n <ur pollution when rosiBared '.its e;;i': jr-.;*-- cl frw Mw. Is context 0* the refar^nce to Crwlloy, sc ni, Cor.-oss* a ns si* Tt'ip'.rabVs ?i1>er3 `, I would aas as th:.t 1 f'v>? vores ''ct;v. ;* j. ;rr-c of fro fibcr3' rafsrs to thk presence of asa;iv ffp-- cf fliers ctivv .n3oe.-stoft in tne aticoattaro. However. in the ant'?.- yc*i nave -uyc:, ic?*v.r.. t iAt 0rodsn^tnb 1^, tda 'vcria nab03toa ' on; ' fibn r . Tb.efi; 0r1, to t c. - coon.riwnai rtncer, and aspecioil/ cna Int^rostad in baX pr*asj*, ona -.ijns gst thft bapresBion tH-`t -r. :so fivs worts r*rxar co ohi prtsanc of ronaidorebl ntbaotos flb-;r it th.' air frcn ot.:'?r 30urcc?fl. I fo not lc-- i-'.t /on lutcnued to infer thlj. Mr. v, n. Lynch of Health, Iducax;on ^ Welfare April r , 1963 I vs3 unable to reach you by phone today, but ill speak to Howard Ay r. He suggested tac possibility that you might want to del.te the last eight words. However, since you probably do vant to reference Dr. CralleyTa presentation, 1 might suggest that you use some slight raodifi ;ation, such as, "when compared vith sources of free fibers, oth.-r than asbestos' or, less desirably, and I do not think what you mean, 'vhen compared with oth ;r sources of free fibers, ia addition ta asbestos . I hope that you will be able to modify this last sentence, especially In view of your departments efforts to prevent any possible misuse of your words. V:ry truly yoitra, Dr. Sidney Spell, Director Corporate Beseared a Development SS/rs :e; Mr. Howard Ayer - HEW, Cincinnati Dr. Lewis Crallay - H3W, Cincinnati bcc: H. M. Jackson - Dtf^ J. Solon - DH X. V. Linde11 - Atb 1 T ,i P. Baines - DH ?. L. Pundsack H. G. Koch W. C. Streib S. M. Fenner COPY Qt2searcn arid :fcv tmbe r 2'.', 12 : 2 'i *v. Srr.ith - 3rak-3 Linina Wear Cus. _ :i".i 3`".g'.csir.c th.r s g e nv 31 g g 3 s c g r. t a i n 1 r. c cv. " h V* *2 ~ 'h- -ra!?-s - thi 10-icv/ing ca rz: I i 71 \ q q ' i *'-s * r C_':i v: '. 'v s^o *rt Ch"rolet ~C -23:?/?C- *; :; 4; ?C - 5 34 .'*0': 313 tr.iite scravzmer.t 12-5-3 a:. 1 - j * - 3 ?; i ^ ? 3303 --13.3 VI11 - -- ~ a v'. ivi--> *. V .-S( Oind thai -h COTiO -S"3 ' ob iT.aZj.G7i a T\ ; zrzrn the a r s n. zu 1 ;i b o r `dcr i r. *v*. t L .nine rhea~ e I a =. e g ar. "i i t v-- 4 +S ^ 1 */. -- a * k. i no w ^\_ v * --\ t* ^ X* * 1 ft Johns-Manville Rrtftpdrch 6 I.O(|inpcrinf| Ctillcr 1` O Hox ISO Mrinvlli". N J 0B8jt (?011 )?? W>00 September 6, 1972 Dr, M. G. Jacko Materials and Processes De-partiuent Bendix Research Labora tori.es Southfield, MI 48075 Dear Dr, Jacko: Wo have finally completed the analysis of the brake lining wear debris you sent to us. There sampler v:ere described as follows in your letter to Dr. Spoil of July 5 , 1972, Sample No, 1 - Vehicle Test 1 J-M No. 4123-58-1 Detroit Traffic: Schedule Right Front Brake Surfaces Sample Sample No. 2 - Vehicle Test 1 J-M No. 4123-58-2 Detroit Traffic Schedule Right Rear Brake Surfaces Sample SamploJtto. 3 - Vohicle Test 1 J-M No. 4123-58-3 Detroit Traffic Schedule Right Rear Brake Airborne Sample The fiber content of the samples and the weight, loss on ignition are given below. The fiber content was determined by the rub-out procedure which 1 believe v?e explained to you at the time of your visit to our laboratory. No. 1 NO.. 2 No., 3 In.i tinl Sanp U* Weight (mq) 50 ,.78 Kc.i cilit of A: :h After IctniUou 0 400C(mcj) 4 3 ,. 50 Weight boss on Ignition 14 ,, 41 46,.50 ?\ .. 10 33., 1% 45 ,.70 30 .. 20 33 ..91 Total F ibcu* i n Sample (inicrog rams) Percent. Fiber in Original Sample 2., S4' 0,. 00 5 0 ,.98 0 ,.002 2.. 73 0 ..006 Wc wore unable to determine the element distribution because our emission spectrograph has been disassembled lor our move to Denver. Dc . M, G. Jaclo September 0 < 3 9 7 2 Page 2 If you have any questions regarding these samples or pro cedures you can contact Dr. ttpeil. He will be available through the month of September. hfter that time you can contact me in Denver. Our mailing address and telephone number in Denver will be: Johns-Manvilie Corporation P. 0. Box $10 8 Denver, Colorado 80217 Phone; (303) 770-1000 Very truly yours, J. P. Loinrwpber cc: Ur. S. Spoil 1 ^ + Iteseurch & Kiigincering Center September 50, 19h6 K. V. LindeH, Asbtstofl Kaaaraoua Dust Upon our return from Anoootoa, S. Spoil anti myself met with Dr. Ken Smith, II. G. Koca, Research Manager of Packings and Friction Materials, and other nowi/trs of the Basic Research group to discuss the status of the program on brake lining hunts. Since this va3 a subject ve discussed briefly with you, I thought you night be interested in a few cf the essential details and conclusions reached at this meeting. The brake lining dust sample vm collected by wearing a brake against a bloke drum with the whole assembly enclosed in a boxlike apparatus. As the brake va3 worn, 130 cfm of filtered air was drown through the system mid the airborne dust was collected on a Millipore filter. Dust remaining in the brake drum wa3 qIgo collectod. The airborne duat was illustrated in the electron micrographs which vo left with you the other day. X-ray analysis shoved this material to be amorphous with no crystalline structure, although by spcctrographlc analysis there vaa sufficient M^O and Si02 In the proper ratios to account for the original chrysotile in the brake lining composition. Rubbing cut the agglomerate Bttusfl and examining this under an electron microscope shoved evidence of some small fibers reduced to their ultimate fibril diameter. The anouut of such fibers is difficult to ascertain, but testa are under voy to get the best guesstimate. Gas analyses of the fumea given off during these tests have not been successful, and we have not been able to determine na yet whether any heavy organic C-usea were present in the effluent air. You probably know that Dr. Ken Gnith had previously submitted samples of brake dust collected from the druns of other pilot p1 nnt. .tar.tn. This material had been sent to the Industrial Hygiene Foundation! In Pittsburgh for intratracheal ar.irr.nl tents under the direction of Dr. Paul Green. The results of these original testa should be completed by November to nee if 'aabcotoa bodies" are evident. I-r. Smith planned to submit samples of this new airborne material to the same location for .Additional tents. Dr. Smith advised me that ho had discussed this matter with Dr. George W, Wright Director of Medical Research, St. Luke's Hospital, Cleveland, and as I understood from, you, a member of your scientific co:fJiittee on occupational health. Dr. Smith said that I)r. V/rlyht. wnt Irj agreement raid approved of the Pittsburgh location as|the bent nines to conduct these teste. Gpcil and I penned . aloe}'; to Dr. Smith your 1nntructions that the Scientific Council should be used tc detcirinc the best location for such studies, and apparently this Via3 been done with the proposed program. V. Lltkcltfll, /.".bonton :>pte&bflr 30, It was agreed at IhJa '.looting that the technique lined to collect the brake di: n t sample ahou'Ld be described nud il lust rated to cumbers of the Hygiene Foundation ar.d any others you foei should bo Included from the QAMA Occupational health Institute or Scientific Council. Tn this vay, the technique of sampling as well as the modi cal results would be understood and approved by an outside agency. A similar approach vould be taken on nev methods of identification which night be developed. otur.-plog of sir dust collected In Detroit under the direction of hr. A. J. Vorvmld (Wayne Sta^g University) I vi 11 be sent to Research for examination to determine if asbestos fibers are present in particulate natter collected from the atmosphere, and if it is, hov much is present. You probably are fazr.iliar with nest or all of the above, but I cm taking no chances of a breakdown in comraunications in this important matter. eh cc: 5. Spell File V. C. 3trelb Votoorch li taeioooriag Coator toooter 13, 1963 B tellty ftrokt Ltnlag Uic port * fit*. **** Twa vill mcoll that turLof fait moot tlilt to tte Btmrch contor, Pr. ,L v dsltfc matlootd 4 meant theory that ubsitoi fiber* freed in the `Marina bt heatae algfct ten mi pathological effect#* Mr Koch Tati1 obtained boar duct* fra three omi had X vouid appreciate y*r ete* * jl--lBlng tbeee tecro#*opicaUy to mo if you eta identify ubiotoa fitoro *in thla aterlel. x MU#jva ior* refuMt (n #3*5) to orarthi* J^YV'-V >* w GTtt ** ;.rv 1 m alto atteehlng the pertinent correspondence tad raid like teoaU your attention to Dr faith11 re^oest for the aeteriel regaining after ;*.--, -- - .,,,; ., tould you pleaee lot m too* ebeo yen ha*e comleted your eaadnation, at ehioh tine n coo again got together vith Br telth to detexalae If any teditlflul vork U Required. tC* *;- >1 WB/* Ml t. V. frdtk, 4U C.'ftdth ^ t t. BUir f. 1. FundMak B. 0* Coeb fii V. C. Btielb PRODUCED .r is'* n'-A- n,;-- v. ;; -. ' r. : ;:... * c ,p Av .' ... *. -V* '.^aV !\ ! V S-, V:-'or . . - "i * . v*- yv y+rh 1 V ^ ' \ V' V ' ; -Vn- V . W- -C', Sjreib, Research '*;}'$ f .'.. -> j..? :-\'M : * 4:-;'; . ->-: * -'.-C- 'Brake, Iiin'irtg Wear Dus / >; \\ i " `i. '"You have.received h copy of 'H. G. Koch's letter to me of ' '. .f*m-A `floveinber 27, 1963, on this subject. I am forwarding th* :'} i^V'^ three enveloped containing the,dust to you for analysis. ; 'A *. As discussed on my recent visit; 'X wonder if you could ' 1 :'[$^/v^liave tjiis duet analysed to see :if there axe any free and * '* v ' *v *;^'.recognizable-asbestos fibers.in it? If there is any dust . -------- ^---------------- - --------------- *-- might llTce to the Industrial /fWZ shall be very pleased to visit you again at the Center to * obtained. PRODUCED M - 83 . Dr* K. W. &dth - GH Research and Engineering Center Novber 27, 1963 Pile: 456^3 Brake Lining Veer Dust I am enclosing three envelopes containing dust removed fraa the brakes of the following cars; Car Mileage Ca&et Newport Chevrolet PC*2308/FC-3049 PC-594/EK*l6l6 Inllte equipment 2266 miles fU0 Biles 9900 Mies Tou vlll find that the dust consists partly of ferrous particles, presumably abrasion products from the cast Iron brake drums She rsnalnder should be predominantly abrasion products from the brake lining thoBselvas# We can supply information on the catposltloo of the brake linings used in the first tvo oars* She third oar vas equipped vlth coapetitive lining, a cexposition not imovn to us, but undoubtedly containing asbestos fiber* C. L* Meserve B G* Koch PRODUCED JM-83 . JOHNS-UAKYILLE RESEmCH AND ENGINEERING CENTER R*poi Date 456-T-S6 January 20! 1964 Title: WntJJMHIC AM) I-RA* DlFmCTIOB AHALTSBS OF fiBAB LZSCK VSAB POSTS Redacted byt V. C. Streib - Beqoeet Bo. FD-345 JM CONFIDENTIAL. fo r f t n t n l AifrftirtfcM o r repvbUraiic*. SO-ttAHT Three todies of brake lining veer hist were trail ned patrographicilly to determine whether chrysotlle fiber can be distinguished in this type of Mterlal. Two of the copies were also examined by X-ray diffraction for confirmation. Ihe temples were free the following brake linings: 1 1963 Coast 2 1963 Pontiac 3 Chevrolet 6, lallte Tr1r?**g Petrographic exmnlnatloa showed the following: She dust fren the Genet lining contained an organic binder, plus nail percentages of quarts, magnetite, carbonates, talc, and (rarely) a few ehiysotile fibers. Chrysotlle in eists recognisable under the microscope constituted less than one per cent of the total* Die dust from the Pontiac lining appeared similar to the one from the Qenet lining, showing the seme components in amounts. Only an occasional bundle of chrysotlle fiber could be detected after prolonged earninatlon of several slides* The Chevrolet brake lining dust differ* somewhat frm the others, in that it costal possibly 10 per cant quarts. Talc appears to be absent. A mall amount of graphic appears to be present, but was not positively identified. An occasional mall bund 'of chrysotlle fiber was noted, as in Samples 1 and 2. X-ray diffraction results: Bust freB Cast Lining quarts chrysotlle talc magnetite weak patters . trace trace . trace Bust from Inlite Lining of CbSTTOlSt iron quarts magnetite lbs "tract* of chryeotile detected by X-ray diffraction in the Cemet lining dust could possibly mscuBt to as mash as 3 per test of the total* This would indicate that in addition to tbs occasional fibers seen microscopically, there nay be some Notebook Id. 2910, p $2; 2864, p 88 fib 456 PRODUCED JOHNS-MAHVILLE RESEAkCH AND ENGINEERING CENTER JUpO* v. ^56*T-86 Soamary Page 2 finely divided and possibly' coated fibrils not recognized under the light micro scope* Failure of X-ray diffraction to detect say ehrysotile in the Chevrolet lining dust seta the ehrysotile contest of this smnple as veil belov 5 per cent* Tht Pontiac lining sesple vas not examined by X-ray diffraction* but the Incidence of microscopically recognizable ehrysotile in this swple Is of the same order os In the Comet Mgpla* Contents: flunmsxy only* Approved F La Pundsach deported by X-ray Diffraction by (/si F, M^Sourty t ~ eh ec: Ka --^ CT---- " . C. F. Saseveiler, SH A* C. felth (3) ? ! Fuadsaek c* Strelb H. 0. Loch D Bailey J P. Mcflourty Libidiy (2) JM CONFIDENTIAL A-ftn e r** 4k trik iik m o r r*p* PRODUCED tM - M _......... JOHNS-MANVILLE RESEARCH AND ENGINEERING CENTER Report No. !l56-2506 Date December 19, 1966 jjf e. STUDY OF WEAR DUST FROM BRAKE LI'iOG ' Project 2550 . .' SUMMARY 'i 1 si ' Brako lining wear dust was collected on a membrane filter mounted in a box which surrounded a brake run on an inertia dynamometer. In addition to chis airborne fraction, the dust that settled to the floor of the box and that which remained within the brake was also collected. A total of 6-1/2 grains of dust was collected from 2150 stops during a total time of about 110 hours. The airborne portion was 2.7 grains. Most of the stops were made from 35 miles per hour at 10 ft/sec^ deceleration, interspersed with stops from 50 mph (about 10 per cent). The a.rborne dust was examined by light microscope, electron microscope, X-ra/3 and other means. Asbestos fiber could be detected only by the electron microscope which gave a maximum of 1.4 per cent fiber by weight in the wear dust, although the lining contains 70 per cent chrysotilc fiber. ; l' ihis result is accounted for by the high surface temperature and severe abrasion during even the mild braking of these tests when the average temperature did not exceed 200?. Calculations 3how that the surface temperature at the true area of contact (1 pen cent of'the apparent area) can reach 2000C or more. It is concluded that most of the fiber is converted to an amorphous mineral by intense heat and fine grinding. \ It is recommended that samples of the particulate matter in the atmosphere be collected at suitable distances from highways and the sample examined in the electron microscope for asbestos. ' Contents: Summary, Introduction, Experimental Method, Results, Ap-pcndix I culations), Appendix II (Tables 1 and 2).,, Appendix III (Figures l"*)* ^rid Appendix IV (References). ( (cal ) 9-.' 'I cc: F- o. Colon, OH K. W. Smith, MD -OH Reported by: 9 David Sinclair Basic Physics Section A. C. `Smith (2+3) F. L. Pundsack Att: 5. Cpeil Dec H. 0. Koch V. S. Streib H. V. Gilbert H. 7. Dende D. Sinclair JSJHHS-MANVIUE RESEARCH AND ENGINEERING CENTER ReportNo 1'56'2506 Page , INTRODUCTION Laboratory measurements vers made to determine what type of particulate matter and gases are given off when a brake lining is worn during operation.' The wear of the drum,-usually cast iron, is necessarily included. Of special interest is the airborne dusit expelled into the atmosphere from the moving brake. Previously, some observations had'been made at Johns-Manviiie Research and Engineering Center cn dust removed by handt from a laboratory brake,~ but this is the first time, to our knowledge, that any observations have been made on the airborne fraction. A search of the literature 'reveaied no measurements cn brake lining wear dust, although the rate of wear is sometimes given.2,3 Recently, numerous articled*5 have.appeared calling attention to the widespread use of asbestos in materials sveh as brake linings, floor tile, roofing, asbestcs-cement products, etc. It is us'.'ally assumed that as these materials wear, much of the asbestos fiber is dispersed *nto the atmosphere, thereby contributing to sir pollution and creating a health hazard. This is understandable, since the asbestos content of these materials is often high, 70 per cent in the brake linings used in these tests, and asbestos is commonly considered to be indestructible.^ However, we know of no measurements made to *tost this assumption or to observe the amount of asbestos in urban atmospheres. ! The present tests show that during the wear of brake linings very little asbestos i fibe**" is dispersed* into the atmosphere. Examination of the airborne dust by ! light microscope, electron microscope, and X-ray diffraction shoved very little , of the .original chrysotile fiber. Nearly all the fiber appears to have been con i verted to an amorphous mineral *oy the severe abrasion and intense heat generated > during brake operation.. A point-count made on eight electron micrographs gave an < upper limit of l.k per cent fiber in'the airborne dust. This is not surprising when.one calculates the amount of energy dissipated while operating a passenger car brake. Tt is shown in the appendix that the heat generate1 raises the temperature of the surface of contact between broke lining and drum to about 2^00C. This high temperature occurs cn the surface of the lining at the regicnr of actual contact with the drum, much less than the apparent area of contact Thea' regions of contact are worn away during rubbing, so that the actual contact continually shifts to new regions. As a result, the wear particles of asbestos, resin, eJtc., are heated to a very high temperature for a very short time. Bowden an Tabor^ observed many incandescent hot spots during the rubbing of metals on glass. EXPERIMENTAL METHOD A wooden box, approximately a L-l/2-ft cube with a lucite top, vas constructed tc fit around a 196l Ford brake mounted cn the C inertia machine in the Friction Materi Research Section pilot plant. Figure 1 is a photograph of the box mounted on the bra) e. The left rear side has a conical air in.let wnich carries a l-tt.-scuare Fland fiber glass filter on the entrance, and tapers to a L-in.-square* opening at the outl into the bcx. The right front side of the box carries two 8 x 10-in. filter holders for Oelman membrane filters. These holders are connected through flexible hoses to a 7-1 /2-hp industrial vacuum cleaner (not shown). When the vacuum cleaner vas run, about .150 cfm of dust-free air vac drawn through the Flar.ders filter, over the brake zpd cut through the membrane filters to collect the airborne wear dust. The pressure drop acrosc the membrane filters was about 15-cn Hg, measured with the mercury manometer shewn standing on the box at the right, connected to a petcock * * ' " I < * 1 x. tni _ ~ ~ ~. w. _ J -/v-- AW-. PiU'ur Vf> B JQHflS-MANVILLE RESEARCH Report No. 456-2506 ANQ ENGINEERING CENTER Page ----:**'* V 1 '' - - Since Che interior of the box. vas under, a negative pressure of j/4-in. hn0, it vas necessary to 3eal the feints and screv holes against entrance of dusty ambient air. This vas done on the outside vith DUXSSAL and cn the inside with contact adhesive*. ' The inferior of the box and the parts of the brake and mounting vithin the box were painted white to show up any wear particles that settled out. The stationary hubs atJ each end of the brake drive-shaft were sealed to the ends ofthe box vitV* '1/16-in. rubber sheet and rubber cement. ' VI r 1 gure 1 shows the auxiliary equipment used to measure the relative rate of evolution of year. dust during and after braking. At the left rear is seen a Sinelair-Phcenix aerosol photometer connected to the side cf the box through a petcock. Tn the left foreground is a logarithmic amplifier connected to a Varian recorder on the right, busty ,air vas drawn continuously from within the box and through the photometer at a.rn.e of aboxit 1 cfm by means of a 1/6-hp Gast pump. Since this rate of air removal is about 0.7 per cent of tho total air flow, its reduction of the amount of dust collected on the membrane filters .is negligible. Figure 3 sbws the type of recoz'd obtained during steps from 3? and mi 1*3 per hour at 10 to.12 ft/sec^ deceleration at intervals cf 2-1/2 minutes. Two of the stops vers from 50 mph as indicated and the others from 35 mph. Usually a more or less regular pattern occurred in which the dust concentration fell tc near zero between each of ^evercl steps and then remained 'at an intermediate level for a couple cf stops. 1 1 v The-narks numbered 2, 3, and 1 are calibration points for the logarithmic amplifier. They are obtained by interposing neutral optical filters of known light transmission into the photometer light beam. ' ' figure a is the. resultant' calibration curve which shows -the approximate logarithmic relationship between chart reading and dust concentration, the latter proportional to i ic 'ttered light intensity.' >*or example, a chart reading of 50 corresponds to a dust concentration about 100 times that for a reading of 5. bust was collected during 2150''stops, most of it on two membrane filters. The average temperature of the brake lining was kept at 175-200OF and was measured with a thermo couple set in a hole in the .lining about 1/16 in. below the surface. The temperature was. kep^ lew, in'order to simulate average braking, by increasing the time between stops to 3-to 4 minutes when overheating commenced. As indicated earlier, this tempers ture is far- below the instantaneous surface temperature (see Appendix I ). RESULTS Three fractions of wear dust were collected: 1. Airborne dust collected cn membrane filters: 2.71 gm; 2. Du3t removed from within brake after completion of test? 3.5^ gra; x 3. Dust `collected from within box after completion of test: 0.214 gm. These fractions all include seme cast iron worn from the drum, about 1 gm total. The samples were analyzed for ignition less, by light and electron microscope, X-ray spectrometer, emission spectrograph, infra-red spectrograph, and Coulter particle size'analyzer. In addition, air samples were withdrawn from the box during braking an j 1 sVmvr? t'he results obtained. JOHnS-MAHVILLE RESEARCH AND ENGINEERING CENTER ReportNo U56_256 Pa* 2 l x Table. 2 snows the composition of linings used, It is seen that the finished lining is about !0 per cent chrysotile fiber after the water and other volatiles are driven ofi The total weight .cf sample collected, 6.16 gm, is much less than the measured weight less of the brake shoes and drum: orinary, ^.0 1 secondary, 7.0 1; and 2 *1 gm, k However,.' the accuracy of* these weights is questionable because cf the heaviness of -v the shoes and the drum. *4e feel certain that negligible loss of dust occurred during the test^, so that ve cannot account for the discrepancy. \ 4 i } f " l.-n- JlYl J0H1S-MANYILLE RESEARCH ANQ ENGINEERING CENTER Report No. ^5 6-250-6 Page V ' '>* !t,r tc iu r* . APPENDIX I . Calculation of surface temperature of lining. These tests simulate a front wheel brake of a 1961 Ford, designed to decelerate 3C.5 pet cent of the car mass, or 1270 pounds. At a velocity of 50 mph = 73.5 ft/sec ' the kinetic energy of this mass is 106,000 ft-.!b or 136 Btu. At a deceleration ' of 10 ft/sec^ this heat- is generated'during a stop of 7.35 seconds1 duration. During the first second, the average rate of heat generation is 3^.6 Btu per second . - 8.. 72 x 103 cal/sec. This heat is generated over a total lining area of 52.5 S(1 in. (21'x 2-1/2) rubbing against cast iron. ' . Bovden .and Tabor^ give a method which allows a calculation of the true area of contact. Their experiments on metals shoved that the actual area of contact is directly pro portions! to the load. As the lead vas increased, the points of contact1* flowed , plastically until the area of contact vas sufficient to support the load. In the > case of less ductile materials such as brake linings, the points of contact would ' be crushed until the load-bearing area vas large enough so that the crushing strength vas no longer exceeded. 1 j For metals, Bowden and Taber found that the yield pressure is three times the tensile strength. tTe make the sane assumption for brake linings. .Johns-Manvilie Research re port l=6-T-bU, received from A. J. Taylor, gives a tensile strength of 1590 psi for a lining similar to thdt used in these tests. The yield pressure is then pm = U770 psi = 6.87 x 10$ Ib/sq. ft. . *. According to the definition of the yield pressure, pm = L/a, where D is the load and a is the real area of contact. The load on the lining nay be calculated by equating the tqrques about the axle of the simulated car. L'h* torque on the* tires :s . mdR - 127C x 10 x 1.09/32,2 Here, m = mass decleratejl = 30.5 per cent of total mass of car = 1270-lb mass. . d - deceleration * 10 ft/sec" - (10/32.2)g J F. - rolling raciua = 1.09 ft The torque or. the brake lining is '1 ju Lr = 0.1 x 1 x 0. ^63 Here, = coefficient of friction - 0.** . L " load r - drum radius = 0.^63 ft Equating these two torques gives the load, I. = 2320-lb force. JlVl *The roughness of'even the smoothest brake lining (10-microinch average} is about 2500 times molecular dimensions. JQHnS-MANVILLE RESEARCH AND ENGINEERING CENTER RcportNo. ]*56-25C6 Page ; i ' The real area*of contact is given by the ratio of the load to the yield pressure .. a = L/pm = 2320/U770 = 0.^3? sq in. '' Since the apparentjarea of contact, A = 52.3 sq in., vhe per cent real contact is 4 C.93 pe.v cent. The percent real contact is alternatively given by the ratio of % the applied pressure to ti>e yield pressure. T.ie. equation used to calculate the temperature is given by Carslaw and Jaeger.^ Tne` maximum temperature of a strip* (the .lining) sliding over a 3emi-infinite .medium (the drum)'is given by , ' T= maX 2JS1 q /77V Kcd ' ' 3P ' q - 2.78 x 10 cal/sec. cm'* = rate of heat generation per sq cm of real contact ar 1 ='. 26.3 cm - 1/2 length of lining X = 0.111 cal/cm*sec.C = thermal, conductivity of drum 1 . c * 0.1189 cal/gmcC = specific heat cf drum d = 7.5 gm/cm^ - density of drum \ Y - 688 cm/sec - average rubbing velocity ,of lining over drum during first second, ' 1 These values give = 2ltOC near the beginning of a stco from 50 miles oer hour at 10 ft/sec^ declaration. . - For a stop from 35 nph, the maximum temperature would be about 2000C. 5 1 'JT g c / U '" * ---- U / U . .'i jX v l The equation is derived for a moving heat source Since the conductivity of the . . /cl,*1 , - <.1 I -> y r >0 r>. V><1 h>*Ao i-oin o e o haaf ^irr'i'P . .UM.CONrimrrTATj. Not fur general distribution . or republicntion. APPFNi-CX II Report >i56-?506 Fajre 7 ., TABLE 2, BRAKE LINING COMPOSITION ^ r SC-l solvent w" Polyrez 2231 cashev resin 3M Company NC 320 cashew resin Water Horn Carbon Black Coal . \/hiting Iron Oxide, Red Hyear 1411 ' Mapico Baryte e Luminite Cement Fiber 1 Primary shoe PC 3504 ? 2.06 4.12 4.74 7.62 3-09 0*62 -- 5.16 6 3.51 -- 1.03 0.82 2.78 0.52 63.93 IOO.OO56 Secondary shoe PC 3442 * 1.5 5.0 . 5-2 8.4 2-5 0.6 0.0 11.0 3.5 0.3 1.0 - - _ 60.0 100.0056 J. M- C O N FID EN TIAL. fo r f t ru ra l diM ributio* o r npublicatum . l J0HNS4UimLLE RESEARCH AND EH8IREERIN6 CETER APPENDIX III Report No. ^56-2506 Ps^e 8 JQHNS-MANVILLE RESEARCH AND ENGINEERING CENTER Report No Paic 0 APPENDIX III Figure ?, i d .u n b u /io ii o r rtp u h lK o vo n . J. M. C O N FID EN TIAL- **'o i f o r [.M . (VJ!' I l')Kl! V I ,V,. rI"i I'^r A1 KNIM / I I [ l. - ' JOHPS-MAHYILLE RESEARCH AND ENGINEERING CENTER ReportNo. ''56-2506 Pngc 11 . f .i APPENDIX IV References _ 't r' 1. Research,report U56-T-86. January 20, 196U, "Petrographic and X-ray Diffraction Analyses of Brake Lining Wear Dusts", D. Bailey, J. P. McGourty. 2. Mechanical Design and Systems Handbook, Chap. 28, p' U3, D. Sinclair, McGravHill, 1964.* . ? "The Fundamentals ot` Asbestos Friction Materials", R, T. Halstead, Paper Trade J ' r.8, ? 30-33, March 2, 19W. h. Biological Effects of Asbestos, p 196, J. G. Thomson, H.f. Academy of Sciences, December 31, 196b- c. Ciiem. Week, September 10, 1966. 6. The Friction and Lubrication of Solids, Vol 1, F. P. Bovden and D. Tabor, Oxford Clarendon Press, 1950. . \ ' . `Report ^56-Int-607, December 8, 1966, "Brake Lining Wear Dust - Evaluation by Light and '"Electron Microscopy", D. Ballny. 6. Memorandum(report Ho. 3-JM-5, December 9u 1966. 9. Memorandum report To. 3-AD-12**, October 21, 1966. 10.' Conduction of Heat in Solids*. 2nd Ed., p. 269, H.S. Carslav and J. C. Jaeger, Oxford, Clarendon Press, 1959* 1 MD EIJSlIjEERtIJfi CEtJl'ER l; ^ ' fc, w^ Repot l No. is ^T-^I Date ^ June 13, 1968 Title: \'tl>VR PRODUCTS FROM LRAKF LINING - IMurc of the Material Becuested by: II,, G, Koch (F-381) SUMMARY Airborne brake lining wear dust was collected on a Gelman filter membrane mounted in an.air tight enclosure (box). The enclosure contained a brake assembly which was connected to an inertia dynamometer. Wear duct vas, collected at three different temperatures (phases). The average temperature of Phase I was 175F; Phase IIj 330F; and Phase III, 550F; simulating various traffic conditions. In addition, wear dust was colic''tod from the brake assembly and the inner surfaces of the scaled box. In Phase I a scries of sets of stops were made. The airborne dust was collected at the end of each set of steps. Only cr.e set of stops was made i.n Phases II and III. A material balance study was made between the weight loss of the brake shoes and drum, and the'amount: of dust collected from the three sources. The airborne portion vas approximately 48 per cent cf the-total dust collected fron a total of 2926 stops. Tills value is high because all dust samples were contaminated with iron and to a lesse: degree with stencil ink used to spray the inner walls of the box. The source of the iron is from the brake drum and from areas on the brake bucking plate where appreciable metal wear was rioted. Analyses show that most of the contamination oceurri during Phase I. The actual, amount of dust collected was about 30 per cent higher than the weight loss of the brake shoes and drum because cf the melal wear of the backing plate which in not weighed. The amount*of dust collected from Phases II and III was per cent of*the weight Logs of the brake shoes and drum. This difference is partially attributed to the Ions of water of crystallization of ebrysotile and volatilization of organic material. ' Chrysettle fiber vas detected only by the electron microscope technique. The maximum concentration of fiber in iho airborne clust was found in Phase III to be 0.55 per cent On the ax um and in the box composite the maximum fiber content was O.oJ per cent (Phase I). - wue to thf severe abrasion and heat generated in the braking operation, the Dulk of the fiber (TO per cent of the lining) was converted to an amorphous.silicate. The amorphous silicate fcrtr.cb ,appreciable amounts cf forsterite in Phase III, indicating * hat surface braking temperatures reached at least 6000. Tne only organic constituent actually identified ir. the wear dust was c ishev resin, Audi lion':1 small r components wore detected but not identified. A phth ilate plasticir.er, a c ntaminant from stencil ink, was present in all samples examined. .ioiins f.wliVILLE RESEARCH Ann ENGINEERING CENTER t v Report Ncj. hrf-'E-'jh S2 Thiti stud/ is a continuation and expansion of the work begun by Dr. Sinclair. Report No. 456-2506.) i. . For details see "Results of Analysis" of this report and Memorandum M456-336. (See Contents^ Summary, Materials Submitted ar.d Methods of Analysis., Results of Analysis and Photomicrographs (Appendix l). Reported by 'S. V, Wegrzyn Analytical Chemistry'Section X-Ray Work by l^uU^aciAk. T~ .T 13 . M^nurlvb Analytical Chemistry Section Spectrographic Work by kSJJ. Suthe i*land Analytical Chemistry Section Microscopic Work, by _____ L !/, Li - ______ V. Af Bailey f Basic Chemistry Research Section dl 1 cc: Chromatographic i H. i,\ Smith Analytical Chemistry Section 5 K. M. Jackson - PK J X. V. Lindell - Aso DK F. L. Fundsack (2+S) S. Snell J. Doci . E. M. Fonr.cr H. r\y> % Koch H. F. Rcmde C.. N. Thompson s. v. Wegrtyn Library (2) research AHD ECCKIEEOT CCEUTER Report No. 456-T-S^ ^, 1 ' \ ' MATPUTALG ClUltMI.TTFb run MbTlKTC OF ANALYSIS Material.-; Submitted '' Laboratory Index No. Doscr; rr.ion Asr-44-i A97-UU-2 .I A9T--WV.3 .. ^ Airborne dust Sample 2, Phase I ' Airborne dust Sample 6, Phase I ,i Composite dust from .drum and box, Thase I A97-!;Ii-4 Airborne dust Sample 1'3 Phase II A97-l^-5 Composite dust from drum and box, Phase II A97-44-6 Airborne dust Sample 1, Phase TIT. A97-UU-7 Composite dust drum and box, Phase HI Only the above sampler, were analysed and the drum and box samples wore composited. Methods of Analysis - The amount of airborne dust was determined by weighing filter membrane before and after collection'. All other dust samples were collected by vacuum and weighed. The samples were submitted for the following analyser cr examination: cpeclrographtc, X-ray, infrared, microscopic, and gas chromatographic. *nh~ amount of ehrysotilc fiber was determined by the point count method that has been used for determining the amount of fiber in water samples. . Materia" Balance RESULTS OF ANALYSIS i 'r x Only in Phabe I were sets of dust collected at various stops to duplicate previous work.. The regaining phabnn had only one set of stops. The data for Phase I is as follows: Run lieu ! Vet Stous Grams of Airborne fust. Collected 1 2 a -u 5S Total 6 (oil leak) 136 167 139 1*39 12^9 2J>b C.2520 0.3330 0.2460 1.5036 H.6067 5.y!H3 height of dust i'rcm br akc assembly Weight of dust iri box 'Total dust collected in Pho.se I 6-3530 2.9630  i$rjMii beseapch AM EflGIllEEninG GEtHER Report No. 456-1-9^ I'W , 2 The folio/in^ table cor.Uii.no data from the three phases; Phase 1 phase H Temperature 1 Number of stops '.Total dust collected (gas) Airbornedust collected (gms) * 175F 2146 15.^973 5.9^13 33CF 720 1.7256 1.3561 Per* cent airborne dust collected 38.8 78.6 uoss in weight of primary shoo (gms) Lross in'weight of secondary shoe (gms) Loss in .eight of drum, shoe (gms) 2.805 8.390 0.605 0.855 2.210 0,680 Total less in weight cf brake assembly 11.800 3.9^5 Phase rII 550F 60 8.7^35 5.1218 58.6' 5.1*20 12.370 0-976 18.766 to+al dust collected weight loss of assembly r Totals ------------------ --- i Airborne dust All dust Per cent airborne dust Loss in weight of brake assembly X 100 120.6 1 * 12.4192 2^.7664 48.2 34*514 total dust collected____X 100 weight loss of assembly '{*\.6 ' 43.7 16.6 It is obvious that Phase; I is heavily contaminated. About 30 per cent more total dust vac collected than the weight loss of the brake shoo and drum. The total dust collected in Phase II and III is I3.7 and 46.6 per cent respectively, of the weight . loss of thf) brake shoos and drum. The reason for the lower values is, ir. pare, due vo the dehydration of tip chrysolite arid do compos it ion of orynnic components in the lining. Details of the contamination are found further in this report. It i-s interesting to note that the secondary shoo wears from 2 to 3 times faster than tho primary shoe. Discounting contamination, the amount of airborne dust collected per stop in 2.5, 2.4, end 35*3 milligrams per stop, respectively, for Phases I, II, and III. The rate cf accumulation of airborne Gust is about 3C times E rea t r at 5 50K thu n for oil her of t he 1 owe? r tempo rat u 1 e a. JOliilS-MAfiVILLE RESEARCH m EflGIKEERIUG CENTER \ Report No. 4J6-T-S4 Page ' 3 Spgctrographic Analysis (per cent in dry basis) Sample No. Phase I Phase 11 Phase 11] 2 g-- Composite* 1 Composite* 1 |Compos] Xsr.ition loss at 8C0F '450 (approx.) 3IO2 (approx.) ` Ft^O^ (approx.) by diff. A]23 b23 BaO CaO , CrgO^ PbO CuO . . 1 1 5 Mi^O^ MoOj NiO . 1 Tl02 ^ V2C, J Loss on drvinr. at 103C 30..3 11.4 20.2 19.0 15-7 17 9 L7 9 lo 24 21 14' 24 21 25 0.7b 67 0.40 - 0.24 0.22 46 0.^0 0.2k 31 0.6c - 0.31 36 O.63 0.15 O.JO 1.0 0.90 , 1.1 1.6 1.7 2.8 0.44 o.li-o o.ie 0.42 1.7 0.03 0.12 *- 0.31 0.07 0.35 0.02 Q.4o 0.30 0.2k 0.4 0.12 0.02 1 0.1? 1 - 0.30 0.06 0.20 ,0.10 0..14 C.lB 0.2C 0.17 3.3 o.yo 1.2 0.0c 1.7 <0.001 0.C014 2.7 2.0 O.OC13 <0.0: 1 <'0.001 2.1 0.7 1 0.6 16.9 15.8 20 25 21 25 39 O.67 28 0.76 -- 0.29 O.JO 1.7 2.5 0.21 c'.ko 0.42 0,42 0.0]/5 0.06 C.23 - 0.23 0.21 ' 0.22 0.0a 1.7 <0.00] <0,001 0.4 Nil #The composites are dusl samples from the brake assembly and the box. Analysis of Diun Filings (in per cent as received) Iron - ma^or Cr - O.Obfi Cu -0.17 Mg - 0.0013 Mn - 0.33 Mo ` - 0.02B ill -0.30 si - 2.5 Ti - 0.C26 ' / ' * joiif!&-r.ift;:viLLE research AtlD EMGIHEERKIG CEUTER Report No. ^56-T-^'i Spectrogrnphic analysis shows that each duet sample collected is contaminated with an appreciable amount of iron* particularly Sample 6 and composite of Thase I. The iron content of the brake linings is at most several per cent by inspection of the formulation. It is estimated that there is roughly a 25-35 per cent iron pickup from the drum and from the area of the brake backing plate- The iron pickup is abnormally high iti Sample 6 ar.d the composite of Phase T. The minor constituents found rn the dust samples confirm the iron pickup based cn analysis of the drum filings. 1 Th^ chief source of the chromium, lead, and titanium contamination 3s from the stencil inks used to spray the inner vails of the box, X-ray analysis shows that FbCrOi and TiO^ are components of the stencil ink. The ratio of Yc0/St02 in each of the dust samples is essentially the same as the ratio for chrysotile. The amount of SiCp and the MgQ is reduced proportionally, in most caeca, based on increase of the content from brake drum contamination. X^Ray The following X-ray powder diffractometer diagrams ware obtained and identified: i Sample ' Identification Pha3e 1, Sample ?. Phase I, Sample 6 Phase I, composite Phase II, Sample i phase II, composite Phase'III, Sample l \ Phase III, composite lead chromate (PbCrOi) halos halos ` halos halos fersterite (3 MgO.SiC^) nagnet i t e f Fc ) chrysotile - possible trace . forstcriue Stone:1 ink (white) Stencil iiik (yellow) j 1 Ti02 (major): tair. (minor) lead enremite (pbCrOi) The breed Jjalcs cn diagrams cf the four s nples indicate a considerable amount of finely divided cr amorphous material, TiC'2 ar.d FbCrOlj are contaminants from stencil inks as confirmed by spectrographic analysis. This is showni by the high level of lead, chromium, and titanium. In Ci urea The fa.'Lovring infrared spectra were obtained: Chart Tlo. U-25S1 Sample Phase 1, Sample 2 Idcnti.ficati.cn amorphous oilicn. or silicate ana trace of organics TT_OCft0 Phase I, Sample 6 .t amorphous silica or silicate and trace of orgnn3.es * JOWMiSMIIE RF.SEf.nCSi AND ENGINEERING CENTER i, \- Infrared (coni' d) Chart No. , Sample U-2584 1. U-2?85 ' 1` U-2586 J Phase II, Sample 1 1 Phase 11, composite ' Phase 1II, Sample 1 'J-2587 "0-2642 ' Phase III, composite stencil ink (white) U-26^3 . v-2Chk ' stencil ink (yellow) alcohol solubles of PJiasc I, f%ample 3 RcpoilNo. U56-T-9U Page 1 5 ^' Identification amorphous silica or silicate and trace qi organics amorphous silica or silicate and trace oi organics forsterite and trace of organ!cc forsterite and trace of organics acrylic resin and TICb> acrylic resir. and a phthalate phthalate plasticizer V-2&-5 elcohol solubles of pW.se I, Sample 6 phthalate plasticizer U-2546 V-26bj1. U-2G48 ' i U-26U9 alcohol solubles of Phase I, Sample 4 .alcohol solubles of Phase II, Sample 1 MIX solubles cf Phase I, composite MEK solubles of Phase III, composite phthalate plasticizer phthalate plasticizer phthalate plasticizer phthalate plasticizer ` The infrarod spectra shovj that in the first two phases, amorphous silica or silicate and small amounts of organic material were detected in the dust samples. In Phase III (550F), forsterite was formed-by the dehydration of the chrysetile and subsequent transformation to forsterite due to heat. The presence of forsterite indicates that ':h$ temperature of the brake system in Phase III war. at least 600C. In addition to contamination of the dust samples by inorganic components of the 2tend] inks, an organic component, a phlhaj.nte plasticizer of the ink, was also detected in most' of. the. dust samples. Acrylic resin vas rot defected. joHas-maviLLE research AMD EflGJilEEfffllG CENTER Report No. ** Pyrolysis Gas Chromatography (FflC) A13 samples were, pyrolyzud under identical conditions and the fragments vero analyzed by gas chromatography. The chromatograms of the submitted samples vere compared with the primary and secondary brak<? linings. . a The original brake linidgs shoved identical chromatograms. The only identifiable organic constituent in the pyregrams'was cashew resin. Samples 2 and 6 of Phase I shoved n6 evidence of cashew reoi'n. The composite of Phase I showed the cashew rosin plus a number of other smaller fragments probably o.ryl~typc components. i' In Phase II'both samples shoved the large cashew fragment; the composite contained more than Sample 1. In addition, tho composite shoved a significant* amount of one othe~ fragment of much lower molecular weight, not common to Phase I. Both samples of Phase III showed almost identical chromatograms consisting mainly of the large cashew fragment. Iii ght Mi croscopy The major constituent of all sampj.es is a smoky brown to opaque material which appears to be essentially amorphous. They occur in flakes and masses ranging in sire fi*cm less than one micron to over .200 microns. A trace of carbonate was noted in each sample. A trace of Quartz v?as found in Phase I, Sample 1 and composite. Phase II composite shoved a trace of glass fiber. *i Electron Micros copy Electron micrographs at a.total magnification of 33>CCO X are attached to this report, i qriV' samples vere prepared by a rubbing out technique to break up loose agglomerates. The micrographs show aggregates made up of very fine material, a few solid particles and traces of chrysotiie fiber. (See Figures 1 through 7) The per cent of chrysotiie fiber was determined by a modified point counting method used, for cetcnaining anoints of fiber in water samples. The counts from the electron plates wore made by the Packings and Friction Material department. The results'* are as folloys; S-.mpl- *) Per Cunt Chrysotiie Phase I, Sample 2 phase I, Sample 6 Phase I, composite .Vha-sc* I", Sample 1 Phase 11 j .composite Phase III, Sample 1 Phase III, composite 1 0.531 0.06!; C.65 . o.oSr 0.255 0.551 0.390 r Research and Engineering Center December 13, 1966 A. C. Smith AsbestQs-efw!ronmentaI Problems Status Report .October-November 1966 !, Packings and Friction Materials Division * Study of wear products from friction materials (J. Dec) During the period October I through November 30, 1966 the wear dust collected from the special dynamometer enclosure was analyzed in detail. The results were unexpected in that asbestos fiber could be detected only by the electron microscope which indicated a maximum of 1.4 per cent by weight fibrous debris. This is in contrast to about 70 per cent by weight chrysotile fiber in the original friction material. David Sinclair has accounted for the difference in fiber content by suggest ing that high surface temperatures and severe abrasion convert the asbestos fiber into an amorphous mineral. He further demonstrates mathematically that the very high temperatures (2000F) required to break down fiber to this extent could be generated at the contact surface of a friction material even during "mild" braking in which the apparent temperature does not exceed 200F. This derives from the tact that the true area of contact In the friction couple is about one per cent of the apparent area. From this work it would appear that the fear of large quantities of asbestos fiber being introduced into the atmosphere as pert of the wear dust of friction materials is unfounded. However, the tests to determine the bio logical effects of such dust, regardless of its fiber content, are not complete, and we are therefore not fn a position to draw final conclusions. 2. Pipe Division A. An Inexpensive inner coating for TRANS ITE pipe (J* H, Swensen) A development program (Project P-22) is under way to develop an "Improved Soft Water Coating for Potable Water Pipe." The present coating, based on asphalt, has become more and more unacceptable due to taste and odor problems. Efforts are being directed toward a clear coating which will not affect water quality. Poly+erpenetype coatings have looked promising although their UV resistance now appears to be /ess than satisfactory. A coating developed within this program will have to be inexpensive and may fill the needs tor a general TRANSITE ptpe coating. It ($ hoped that the Improved soft water coating can be commercial I zed in the first quarter of 1967. B. Effect of water flow through TRANSITS pipe A layout of a system for studying the effects of flow and water composition on TRANSITE pipe has been prepared, and an assignment has been placed on the Engineering Department. Probably this system will not be operational until the second Quarter of 1967. A. C. Smith -2- December 13, 1966 3. Fiber Glass Insulations Residue from flow of air through fiber glass ducts, etc.(G, J. Hannes' Initial tes+s run by the Kettering Institute with Owens-Corn1ng Fiberglas duct Indicated no measurable release of fiber into the air stream. Much more extensive tests are under way now in the C-C laboratories under the supervision of the Kettering institute. Johns-ManviIle duct liners and duct board are part of these tests, which will include a variety of air flow conditions. Complete data will not be available until about March i, i967. 4. Building Products Division A, Degradation products of asbestos felt built-up roofs (J. Q. Trice) The instrument Development Company of Res+on, Virginia, a division of Resources Research, Inc., is preparing a preliminary engineering drawing and specifications for equipment which they propose for the actual weathering and collection of materials. Briefly the environ mental chamber will consist of four components: (a) the mechanical chamber, (b) the radiation system, {c) the air handling system, and (d) the liquid handling system. Detailed information wifi be avail able from the Instrument Development Company by December 15. We now beHeve that the actual samples-for weathering will have to be prepared outside the environmentaI chamber because of the high concentration of material thrown from the hot asphalt and from working with the roofing felts. After the samples have been prepared, one will be-exposed in the environmental chamber and a second exposed on the roof of the Research laboratory so that at least visual observ ations can be made comparing the performance of the two samples. Materials produced or released during the weathering process will fall into three categories: (a) particulate - which wi11 be collected on membrane fI Iters (b) water-soluble which will be picked up by the wash water which must also be put through a membrane filter in order to collect solids which are removed by washing (c) vaporized materials - which will be collected at the low temperature traps in the air circulating system. B. Degradation products of asbestos-cement materials A program for sampling and testing materials has been drawn up. The test program will Include an examination of field-exposed materiel which has been in service for many years as well as laboratory exposure of products. In the case of field-exposed products, since shingles are partially exposed and partially covered in use, it is possible tor us to obtain good reference samples and analyze the changes that have occurred to the exposed surface. A preliminary examination of some vertically exposed normal-cured products after long exposure shows the following. ... A. C. Smith -3- December 13, 1966 Source of Samples JM office buildibgT Manvi I le, New Jersey JM plant, Nashua, New Hampshire JM oIanT, Nashua, New Hampshire JM plant, Nashua, New Hampshire Products Dry process shingles Dry process shingles Flat TRANS ITE Corrugated TRANS ITE Exposure Period 1918-1964 pre-1926-1966 1921-1966 1924-1966 Thickness decrease durirc exposure, inch* 0,003 to 0.020 0.001 0.006 0.012 The small amount of weathering exhibited by these products points up the need for very precise measurements in this test program. 5. Flooring 01 vision Wear products from flooring materials (J. Q. Trice) Experimental work has not yet been started in this program. 6. General Company Research Organic materjal in asbestos fibers (F, L. Pundsack) Cape S Blue, packed in paper bags and In jute bags, was obtained from the Manvilie Pipe Plant, and the organic content extracted. The blue fiber packed in jute bags contained up to sixty (60) times as much organic mate rial as did the fiber packed in paper bags. Jeffrey chrysotMe packed in paper bags and in jute bags Is being analyzed in the same way, and data will be aval labia soon. We are working with a company named Ana I tech to develop methods of identify ing ail the trace organic substances present in asbestos. It may be of interest to note that in 1965 in the United States approxim ately five (5) times as much benz(a)pyrene was released in the form of cigarette smoke as was contained in all the asbestos used In this country for all purposes in the same year, incidentally, more than one-half the benz(a)pyrene associated with asbestos was contained In the approximately 40,000 tons of Imported blue fiber. F. 1. Pundsack ae cct F. J. Solon - GHQ K. W. Smith,MO -GHQ A. C. Smith Research 6 Engineering Center January 25, 1367 ASBESTOS - ENVIRONMENTAL PROBLEMS STATUS REPORT - JANUARY 24, 1967 1. PACKINGS AND FRICTION MATERIALS DIVISION A* Study of Wear Products from Friction Materials (Dec) As indicated in the report dated 12/13, only 1.4% of the wear dust collected was asbestos fiber. No information has yet been received regarding the dust samples submitted by Dr. K. W, Smith for biological testing. No additional sampling of wear dust is planned until information on biological effects is obtained. 2. PIPE DIVISION ' A. An Inexpensive Inner Coating for TRANSITS Pipe (Swensen) A polystyrene coating has been formulated which has shown more than the required resistance to ultra-violet and which meets the AWWA requirements for water-pipe coating. Long term adhesion has been satisfactory to date (two months exposure). A Commercial Recommendation will be issued on or about February IS. B. Effect of Water Flow through TRANSITE Pipe (Swensen) Plant Engineering has estimated the costs of constructing a system to study the effects of flow and water composition on TRANSITE pipe to be approximately $230,000. In view of the high estimated cost, the proposed program and system are being revised. 3. FIBER GLASS INSULATIONS A. Residue from Flow of Air through Fiber Glass Ducts, etc. (Ham As mentioned in the December 13 report, the extensive test program is continuing. Data will be available about March 1. 4. BUILDING PRODUCTS DIVISION A. Degradation Products of Asbestos Felt Built-Up Roofs (Trice) Based on specifications and quotation from Instrument Development Co., Reston, Virginia, an appropriation request in the amount of $25,000 will be submitted by January 27 for an' environmental chamber. This appropriation will be accompanied by a detailed program and an estimated total 4 **V iZ-* " v'TJO A. C. Smith -2- January 25, 1967 cost. Delivery of the chamber is promised for 16 weeks after receipt of order. B. Degradation Products of Asbestos-Cement Materials (Trice) Samples of Steam Cured TRANSITS (COLORLITH) showed a decrease in thickness of less than 0.003-in. after at least 12 years vertical exposure on the.REC test decks. (Normal Cured products showed a decrease in thickness of 0.001" - 6To20n.) 4 The program of finding and examining exposed samples has ' been expanded to include wet and dry process as well as normal and steam cured samples. 5. FLOORING DIVISION A. Wear Products from Flooring Materials (Trice) A program is being prepared to utilize a modification of the type of environmental chamber being recommended for the asbestos-roofing program {Item 4A above). 6. CORPORATE RESEARCH A. Organic Material in Asbestos Fibers (Speil) Research Memorandum #M411-489 (12/29/66) presented a review of the literature concerning the occurrence and properties of benzopyrene in the atmosphere from smoking, exhaust fumes, overheated tar and asphalt, the general burning of rubbish, coffee roasting, etc. The outer layer of a "well done" charcoal-broiled steak was found to contain a substantial quantity of benzopyrene. . Samples of asbestos have been sent to Case Institute of Technology and Mount Sinai Hospital for experimental work thejjvare conducting on their own. Work has continued with Analteck Inc., on improving methods of identifying trace organic substances present in asbestos. Most recent information shows Jeffrey fiber from a paper bag to contain 19-31 mg organic material/100 gm of fiber, whereas samples from a jute bag showed 4 mg at the center and 16 mg adjacent to the surface of the bag --the reverse of information obtained with Blue fiber. Additional tests are in progress. . We cooperated with the Veterans Administration Hospital, Hines, Illinois, who are studying the relationship between asbestosis and mesothelioma, where their work with mice showed heat-treated asbestos gave a more toxic reaction than unheated asbestos. F A. C. Smith -3- January 25, 1*67 Hamster lung tissue samples submitted by the Health Service Institute, Fairleigh Dickinson University, examined by electron microscopy, showed the presence of both amosite and chrysotile asbestos-. etr cc-C- B. Burnett, GHQ F. J. Solon, GHQ K. W. Smith, GHQ F. L- Pundsack M. M* M&cAlpine CEO * J&I-S3 COPT FORM INITIALS DATE BOX NUMBER .< / -3/? SEGMENT NO* NOTES REQUESTING PARTY p/fc* V /fs rurfr/W s*v** 5* gft& If** . Hethodf . The material vu e*eiai&ed aieroecopieally in bright r . cootrut. A portico of the tempi* vu ruhbad out a1 4 electron gride* u outlined In Research report 1*12 var then ehtdev-cut. The rub-ovt technique braA # fractures eolid material. It doe* to a certain arteat fiber, but does oot split individual fibrils. * 1i , 1 Right electron micrographs of the shadw-cut material vertf take*nTtt'*u*"i 'prinltes* ;ht.,a 1. v total magnification of 3G,000X (M 4T* A to R}. Al06.tvq jle^ro^miCTrnermpbe, .*<.-! J of mbted-out natoHal that had not Wa ahadov-eut'and oct alt^rao .WCT0(rrto;6t^1f% 1;- . a vd*aiftfrtaricatliothnapt ahtatedrnnoot fbeaeenaraubllbefidboourtinva^trhaate^Xbean dfo-r^,:oio&oaptarriiali|(f^']i^^V^olibi)^i%>il^ vu obtained* Tvo electron nUro*mhi' of.4ir^bonU'.>raXi;VdaT:.dwf i} *, '/*`^tox this .r.ejp..o~r-t*::'\Tk if.o..rxa<a l and t%%AppeadsiTjc^>f.to. 1vi5s38la '.. By mesnt of i transparent grid ulth viarter-inoa opening pUoed ovarr toe aicrofrepi:* . v ' of ehadcv-eaet materiel* a pointscount "taalyelt ^uaamade ln/vtlffijAe jtaiito1*'liter/ TM*.* dagraiB*4, J Any alongated,1'raetangilArfpariiola tbreCM>Jrf f e*vlrtu^ '*.We . "never** janwamuKEsssi 3^../:.. il Jsl,.-1 I GOTO *****' t rS ::< Fiber content by polnt+count method. (The measurements ware made by J, Ievlev or Friction Materials and the work via supervised by D. Bel lay.) .. The percentage of fibers in a total of 26*5 miti counted, as calculated oc a velum* baala amounts to 1.* per cent. Units counted as fiber ranged free* about 203A to about 600A In disaster, and from 6ooS to about 1.3 sal crona la length. Electron diffraction. An electrco diffraction pattern of a single fiber In .the air-borne sample of brake wear dust vaa obtained. This pattern coincides with electron diffraction patterns which were obtained from single cbryaotlie flbara Discussion The value* obtained by the poiat-coiat method aa outline 4 Indicate that leas than 2 per cent of the Mr-borne iample examined occurs as email fibers. These fibers are of the order of 200S to 600A In diameter and range from 600A to 1.3 microns lo length. Rote also that somewhat longer fibers occur in brake wear dust that vas not rubbed out. For example, a fiber 3 mi crone in length is shown in figure 1, an electron micrograph of brake wear dust that vaa net rubbed out. Fibers of this length are of rare occurrence ip the aamplea examined, and are usually attached to particulate material, aa in Figure 1. Samples obtained from the drum and the box were found to be comparable to the air borne sample In general appearance and fiber content. On the basis of an electron diffraction pattern obtained from a fiber io the air borne sample of brake wear dust examined, end found to coincide with an electron diffraction pattern obtained from a known chrysotile fiber, It la apparent that tcr.e or all of the fiber* in this * ample of brake wear dust still retain the chrysctila structure. Thus, baaed on the methods uaed, the amount of ebtyaotila fiber that can be reccgnited as such in this sample does not exceed about 1.* per cent on a vclute basis. OA^j, Reported by: 0. Bailey f7 Basic Chemistry Research Section cc A. C. Smith (2 F. L. Fundjack K. T. Rend* D. Sinclair S. Spell G. Relmachuaaal D. Bailey Library (2) J Or* hit** ; VKfr'-i-