Document G6kZ7B2v4Ve1E7M024RbbQpvN

FILE NAME: Ford (FD) DATE: 1975 DOC#: FD062 DOCUMENT DESCRIPTION: Journal Article - The Hazards of Asbestos for Brake Mechanics The Haz id s of Asbestos for B.ike Mechanic 2501; BARRY CASTIEMAN. LU CILIE A. CAMAROTA. ALBERT J. FRITSCH. SUSAN MAZZOCCHI, and ROBERT G. CRAWLEY ASBESTOS is the generic name of a group of hydrated disk pads, and clutch facings for the pan magnesium silicate mineral fibers. There are two Jacko and DuCharm c ( U ) estimated that groups of these minerals-- serpentine (chrysotile) and States annually uses 103 million pounds of a am phibole (amosite, crocidolite, anthophyliite, brake friction materials and 4.3 million tremolite, and actinolite).. Ninety-five percent of the automotive clutch friction materials. world's asbestos production is chrysotile. T n 1968 Lynch reported that because of t Repons of epidemiologic and pathological studies friction caused by braking, almost all of the ; ( 1 - d ) reveal that occupational exposure to commercial brake linings is transformed to a nontibrou asbestos minerals enhances the likelihood of a number n d a small fraction of asbestos escapes as of diseases--asbestos and cancers of the lung, pleura, (12). Jacko and co-workers determined that peritoneum, larynx, and gastrointestinal tract. The this country emit 138,000 pounds of asbesto time from onset of exposure to the time of clinically ap of which Cl.2 percent is retained in the brak parent disease is usually more than 20 years. Cancer used of during service ( IJ). from asbestos is not limited to workers who handle the Urakc mechanics have low and imermitten material. 'Iherc are also reports of pleural and peritoneal mesothelioma (tumors rarely seen in the to asbestos. This exposure has been reported fiber per ml time-weighted average (fibers loo general population) in persons w ith fam ily, or microns), with peaks up to 7 fibers per ml v* neighborhood, or indirect occupational exposure to parts are being cleaned I W). T h e standard r asbestos ( J --7). removing dust from brake parts is to blow it Mesothelioma was the cause of death of a man who had regularly sanded vinyl asbestos floor tilef J). Under O A /r. Coilleman, an environmental engineer, we. simulated conditions of this man's work, a maximum Center fot Seienee in the Public InternI when thu asbestos dust concentration of 1.3 fibers per ntl (fibers prepared; he it note with the Maryland Pubh,- Inter< longer than 5 microns) was found in air samples passed (roup. Dr. Enltch u director o f the Center fur Sc through membrane filters worn by a person sanding '' Public Interni. M l. Cornatolo it on ottupoitor.ul >,, vinyl asbestos t$). T i e type of asbestos now used in llitlrn t nf Columbia Department of Human Reto domestic floor tile is chrysotile-- the same as that used in brake friction materials, according to the Asbestos Information Association. A case of mesothelioma in Metti'* ihi well n rtireirch anaciate. Fn: une.mrn Rettati h Project, Em tronmrntal Scieneet Lnbnenh Sinai Si haul ttj Medinnr, .Yew lock ( i h Mr C brake mechanic has been rc|*orted 'll.,*Contmcrvi.il friction materials used in the United Stales for bt .iking passenger cars and trucks contain an tnnilnnnn. Holtimnre County Department of lim it Tear,heel recanti to Uarry Cut!ft man. Morii, lnteenl Unearth (irmtp, JI10 .Vrw Main D r average composition of Ml^wurnt chrysotile By-VvHgHt t imeelily / Maritami, Collejr Park. MJ. 0/1. H Wf Asbestos has been used fur brake drum linings. IM VuU< HSlIft Assoni 8004 1951 PQ ,1 n r l,m f In . h a srvcr.il report* ( 1 1 -IS ) locN of r ^ u r c of brake u r a n i c * ,u , ; C Cs..rt. alternative friction nwtrrwU. .me spectfic hnnvjct in brake repair prari.ccs "In ch would reduce ihe loci* of exposure. Ballirnor6*and Washington Studies In December 1972. (lie Baltimore County Department of Health mailed a I-page mimeographed circular to about I JO eitablishmcnti which provide brake repair service. These businesses included new car and truck dealerships, certified motor vehicle inspection stations, and other concerns advertising brake repair as a specialty. Some of the establishments initially contarted had either gone out of business or replied that they do not do brake repairs. The circular warned that inhalation of the dust from brake cleaning could cause serious diseases, including cancer, and advised vacuuming brakes of accumulated dust. Additional measures suggested were improved ventilation and the use of face masks (19). Tw o student volunteers went to 100 of the places on the mailing list 4 months later to ask shop managers what methods they were using in brake repair. A sim ilar study was started in Washington, D .C ., in August 197J. T h is work was conducted by the Center for Science in the Public Interest and the District of Colum bia Department of Human Resources. O f 136 brake service establishments initially contacted, 120 were followed up. Several new methods were tried in order to improve the effectiveness of the warning. The warning leaflet was more eye-catching and readable than the paragraph-form sheet used in Baltimore; the Icaflcis were handed out by an occupational health nurse to the mechanics thcmselve-- none were mailed; anil followup to ascertain the degree of effectiveness was conducted by the same nurse who interviewed the repair shop managers. 'l"he Washington study was also featured in a lucal television program at the time the leaflets were first handed out. lu u em w ou emit n it stun Tu assure that students trained in l ir.,kc public utauun.il schools sould learn proper health officials met with appropriate vihool c both lucatiuns. At the time they were cuntacit officials in Baltimore and Washington reporte schools were teaching the "blow out" methoc dust removal to the trainees. The standard method of cleaning brakes is out*' with a compressed air huse. In Bahtmor cem (65 per 100) of the brake repair cstab contacted were using this method at the t received the warning circular*. In Washim figure was 9| percent (110 of 120). Moi manager* and workers interviewed had nev about the hazardous potential of brake dust, ably, the responses ranged from annoyance to . lion. O f the 65 places in Baltimore initially bio brakes. II were using either vacuum or wet methods at the time of followup. Four others blowing out brakes, but had improved vend provided dust masks, or both, to reduce wot posurcs. In Washington, only two establishmc changed to wet brushing, but none were va brakes. Four others provided face masks. Into two others decided to change brake shoes in repairs, thereby simplifying the problem removal and reducing the mechanics* exposu The degree of improvement, indexed by the age of establishments converting from blov brake* to safer techniques after a single warn 2J percent in Baltimore County and 7 pc Washington. This disparity probably jnves m differences in the methods of the studies th difference* in the study groups. it may be critically important tu approach ment jt the outset in order to enlist the too needed to implement any changes in pra mechanic who is approached directly v,ith a may simply disregard it. T h e mechanic migh that if the duct were really dangerous, there w. law requiring the use of preferred methods repair. And the employer, if not asked to pa from the beginning, may well conclude that lie be concerned with the matter. The failure tc management may be the main reason v Washington study produced less gratify ing rest the Baltimore study. Brake warning programs consisting mcrclv t warning notices require little manpower, tom other health programs. Also, the effort to ur safe techniques in public vocational school, n t spent. Conclusion Over a 7-year period ending in 19.0 . . Stand.ltd fur tinve.jverayevl exposure to .i .Ik have been reduted finnt s million p.irinltv p U n - J u u sirs voi to * 8004 1952 PQ micro*) fo r .uboiu textile jtlhnis. this reduction it about li-fotd (.V/. P ro m t and scheduled standards cbitii only ip prvtect markers again ,iib c 0 (i$, the dtteate fur which die dose-response relationship is most quantitatively known. The British standards for chrysotile and amosite asbestos, which arc comparable to the asbestos standard scheduled to take cfTect in the United States in 1976, do not purport to provide protec tion against increased risk of cancer ( ZJ,2J). .Previously studied cohorts of asbestos workers were exposed to time-averaged concentrations greater than 2 fibers per ml (fibers longer than 5 microns). Current studies of cohorts with time-averaged exposure on the order of I fiber per ml (greater than 5 microns in length) may provide evidence of hazard at that level, in view of alarming preliminary findings of pulmonary fibrosis in such a cohort, the National Institute of O c cupational Safety and Health has suggested to the Department of Labor that consideration be given to further lowering of the asbestos standard ( 2f). T h e average brake mechanic is not aware of the potential hazard uf airborne brake dust. Nor is he quick to change time-hardened habits when warned of dangers if he cannot feet their effects. Nonetheless, sub stantial reduction in asbestos exposures during brake repair can be achieved by simple changes in technique, with the use of equipment already available in most brake service establishments. In view of the tendency of the accumulating literature to reveal cancer induction from asbestos at progressive ly lower levels of exposure, mechanics should be ad vised not to blow out brake parts and to use instead methods which create less airborne dust. The manufac turers of automotive friction materials could easily at tach a clear hazard warning to every item sold. T h e limited success of both the Baltimore and Washington studies shows the limited efficacy of volun tary compliance with health warnings--the shop managers and the mechanics simply do not have the same regard for a warning that they have for a regula tion. The margin of safety, if any, provided by the current asbestos tand.trtls has been sharply criticized as insufficient l - 1')- While it is advisable tnat brake mechanics at least be warned of the potential hazard of their work, it is also apparent that blowing out brakes will be a common practice so long as health regulations permit it. 4 Rtftttncts ' I. Cooper, W. C .. el a!.: Asbestos--the need for and feasibility of air pollution controls. National Academy of Sctenvet, Washington. D C .. 1971. t. Scliln.IT. | J , ll.vmrmmd. E . C ., and Ohufg. J-. Mortality e- perirrurt of atlwstot insulation - o i l r n . fa 1'fiednigi of the lnicrn.vtion.it Cnnfcrrnst on Pnrumocumuiis. Johannesburg, I960, edited by II A. Shapiro. O J n r .l L'nnrevily Press. <\i|iftuun. Smith Afrna. |97tt. pp I HO- ISO /. Stell, P. M . anil .Mi tiill, 'I'.: Asbrtim and laryngeal carcinoma. ........... .... . . - - I / . , \ u g ,,>, | ' ) ; j I N c-I.uoic. M . L . and Thumpmn. H M e.nit pleura and peritoneum fullui-in,- r|...UIr w<||, dun area Hr J Ind Med H r.| - 269 * I lichen. J . and PntanSa. It.- Mtsothrlmm, leisure. Aeth Environ Health M ) s * - l c t A Wagner, J . C .. Sie*. C A ., and Marchand, f> f mrxnthrlinma and asbctins exposure m the Xoriti Province. |>r | Ind Med 17: 2JO-271 n ^ y j f. Dairyuen, F ., Dabbed, A. F .. and Hina. | .: [ p;rt Pleuramesothelioms. Vorlufiger Bericht ber It s Hamburger. Haunt Praa Pneumof 2J; 1 * 1 j * Murphy. R. L . et al.: Floor tile initalUnon a, asbestos exposure. Am Rev Respir D u IM 174- 197|, . a SuMivatu R. y , and Athinassiadis. y. ; prrlimin iioit Survey of asbestos. National Air Pollution ministration, APT 0 -2 7 . Raleigh. N.C, Harwood, C .: Asbcstot air ftgllwiion from the 1 linings. Illinois Institute of Technology K c u t r Chicago, April 1972, ^ Jacke, M .C ., and DuCharme. R T.- Brake emiuic mraiuremrnti from brake and clutch linings |mm K l sources. Environmental Prorrction Agency Report Ann Arbor. I97J. ^ ffZ Lynch, J .: Brake lining decomposition produces. . j Control Assoc I t : <24-126 (196*). '* Jacko. M . 0 ., DuCharme, R . T . and Somers. J H clutch emissions during* vehicle operation Paper . Society of Automotive Engineers Meeting. Detroit. fJ. Hickish, D. ., and Knight, K . L .: Esposurc to ab l brake maintenance. Ann Occup IK g IJ . 1 7 - | jy IS. Hatch. 0 .: Possible alternatives lu asbestos as a frievi Arm Occup Hyg IJ ; 2 S-2 9 (I9*0t. fd. Knight, h . L ., and Hickiih, D. E .. Insrstigatiotis inn fornu of control fur dust generated dunr.g the dean assemblies and drums. Ann Occup Hyg IJ J 7 - J * 17. tee, C . L : Removing dusts from brake assemblies du servicing--alternati-c cleaning methods Ann O v u J J - J * <I?U). IS fltniley. M |,,: Cnntrol of the use of aibcit.-s-cumair materials. Ann Occup Hyg IJ J l - ) 2 (l-ruy IV l* V Senate, Committee on Commencr T u n c Subst trot Act of |97J. Hearings before the F.niFpnprbcr m uirf Stiicm rm nt H C tiilc n u n *\d Cn< f S C Printing OfTitf. MC. , to pp u \ j ,W (',uenilicr. (J. C Emergency standard fur rsfxnuit dust Federal Register, vul. J6. \ o 2)s, | k c 7 ii ' .V. Guenther, (I. C .. Standard foe exposure to asbesim d. Register, vul. J7, No 110, June 7, 1**2. pp, l | ) l | - H l.ynch, J . R ., Aytf. II. E ., and Johnson. D L lereelaiionthip uf srlerlrd asbestos etpm urr indues. A . Assoc J 1!; SOX-COS (1970). 1. Hygiene standard fur chryso-.ilr asbestos dust Arm ( II : 47-4V (|% t). .V. Ilygirm standards fur airbwrnr .smosne aabrsios dun cup llyg 16. 1- S (197)). 1. Key. M M. Reopening uf asbestos standard Mrmorj Srentler, Assistant Sn rrla ry if l>hnr. (kcupanunal llt a lih Attiiiiniitr.iiiun O lfite uf Techm ral Pul Natinnal liisinuir f**r thsupationat S.ileti and Hr jlih , M d . Marth 2X. 197a. i t ( i f f , H . and lluultuys. A .. Action on atbestus N EnglJ IJ1 7 - | J14, Ik e . 2. 197|. >41 Public Kaoltft Papons 8004 1953 PG