Document 3QQgjYD6LdQDmLRLq4a86b5N3

FILE NAME: CERAMICS (CER) DATE: 1932 Oct DOC#: CER002 DOCUMENT DESCRIPTION: Trade Journal Article - Dust Hazard in Rock Products Industry 14 Heck Products Dust Hazard in Rock Products Industry POanpleyrsDuanstds CDoisnctuasisniionng aStilitchae ANractiDonaanlgeSraofuest--y DCoignegsrtesosf T Lime Dusts Not Injurious HE RECENT National Safety Congress at Washington, I). C, included a sym lias shown a tuberculosis complication. Until ! we have more statistics of people working posium on the dust hazards to health in in dustry, a subject of particular interest to , in asbestos dust we should not say too much OCK PRODUCTS took an ac about the part p!a)ed by tuberculosis in asso- some rock products producers at this time because of the activity of a certain type ot lem t iinv e i tisn t ii nr sd iut s tirni ets/ i f a d * uesat r lpyr oab 1921, when the editor heard from l ciation with this condition." Analyses of Mineral Industry Dusts lawyer in promoting lawsuits for damages, running (in the aggregate) to millions of dollars lviamreiostuosnoprdoudeutcehrad tbheaetn lirmegoaradnedd in the industry for generation not J. J. Bloomfield said in part: During the past nine )ears he had made numerous investigations of the dust hazard in man) Dr. Leonard Greenourg, Yale Univer ohnellpy fualt innotthehatrrmeafutml, ebnut toaf cttuubaelr/?- industrial establishments. He presented a sity, New Haven, Conn., presided as chair man. The first paper by Dr L. U. Gardner, director of Trudeau Laboratory, Saranac cibIumei'ii. aIn6-tphaegeJaanrutiacrley o1n4, "L1i9m2o2 and Tuberculooi" containing a summary which showed that the highest dust exposure was in talc mines, slate fin ishing mills, quartz (silica) grinding plants, I-ake, N Y., dealt with the kinds of dust oypminpioontieumo f onfumtheeroups *lriim e cmf aannud coal mining and granite cutting operations. encountered in industry and their effect upon the lung tissues The second paper by J. J. ifnacf tulirteerratuarned oan stuhme msaurbyjeoctf. exist* Owing to the high percentage of silica pres ent in the dust of quartz grinding and gran Bloomfield, U. S. Public Health Service, Washington, D C, followed with a discus ousTlhye dissucbujsescetd hians Rboecekn Pcroondtuincuts In the June 28, ite cutting plants he found these to be the most hazardous of the occupations which he sion of the methods of determination of dust as to particle size and concentration in the t1Ai9n2c4au,s#eiAssaou#fetbiimos teha. l5i-mpeagaenadrtgicylpesuomn ha"dAstukdnioewdledge of the dust content of the air The third paper by Dr. A. E. Russell, U S. Public Health Service, Washington. dcuursetss afosr potusbsiebrlceulopsriesv.enTtihveesse aanrd ticles received wide and Dr. industrial atmosphere is required," said Mr Bloomfield, "not only for the purpose of de iIn) vCa.r,ioduisscudsussetdy ctlriandiceasl. aInnd tshteatifsotiucratlh sptuadpieers. Mtheirsiiasm foIsrxahredr wmasedleincdaolttoicdemegarkeee her termining the extent of the hazard involved in various manufacturing processes, but it is Theodore Hatch, of the Harvard School of Public Health, Boston, Mass, discussed the JsuobhnjesctH. oHpekrincsonUcnluivsieornssityw eorne tnhaoett very specific effect of also useful in measuring tle efficiency of protective devices which may be used in the pvlaarniotsu,s amndethiondsthoef fdiuftsht cpoanpterro.l PinroifnduPshtriliiapl ttihveesse, bduutstws eraoassqeutuoirtosstAdoefriniptreevtheant elimination of the dust hazard" In discussing the health hazard, he said Drinker, Harvard School of Public Health, outlined the vat.ous n..ihods for protecting lciamuesosanodf tguybpesrucmulodsuiss,tsorwseilriecosniost, "It is now well established that the inhala tion of certain types of dust, such as granite the worker against dust inhalation. as arm d u sts containing silica. In the course of fAcis 10 years dust, will in time produce fibrosis of the lungs, at times associated with tuberculosis. Dr. L. U. Gardner said in part "At first it was thought that aU dusts were capa lRisohcekd Pmruocdhucitns focromllaotcitoend ianndregpaurbd to experience and experiments In other cases exposure to dust may result in the production of a far less degree of ble of producing disease, but with further study it became obvious that different types wduitshts liwmhei,chlimsheosutoldnebeanvdergyyphseulpm fibrosis without notable tendency toward subsequent tuberculosis; this is true of ce of dust produced different effects. With fur ther study it became obvious that dusts con fluawl etuoitsaansy aprroedsuulctero f faaclleedgedw iitnh jury to health due to exposure to ment dust. And finally, there are certain types of dust as t>pified by marble dust, taining silica were particularly harmful and that they produced definite changes in the athnecsee odfusetvsi.deTnhcee igsrethaat tptrheepo"nlidmere which in the quantities and lengths of ex posure so far observed produce little lung lung tissues Today we recognize silicosis as a form of disease which is quite definite There are other forms of changes in the sluanltg**s adnudstpsroavriede deiasstcoalvreeodasinm atthee lroiasilst.--o hTehael Ethdeitolers.ions o f tubercu- fibrosis In general it has been found that those dusts which are high in silica content are the ones which produce a disabling lung tissues which are produced by the in halation of dust about which we know little fibrosis of the lungs most readily. Hence, the necessity for knowledge concerning the "We know man) of these dust conditions are associated with a factor of infection in "All dust, when inhaled, mechanically in jures the lung tissues, and the small par chemical and mincralogical composition of a dust is obvious the lung Some believe that silicosis can not exist without a background of latent infec ticles injure the cells We know that the type of injury varies with the nature of the "With reference to the quantity of dust present in the air of a workroom, it is ap tion However, this is an extreme view, as we know we can produce experimental!) a dust particle." Dr Gardner showed a number of lantern parent that when the dust concentration is high the exposed person will inhale a greater true silicosis In animals b) the inhalation of silica alone slides illustrating the effect of dust on the lung tissues- "If coal dust is present m ex quantity in a given period of time than he will when the dust concentration of the at "Much has been written about coal miners and the factor of infection due to inhalation cessive quantities and silica in relatively in significant amounts, we have a distribu.w.i mosphere is relatively low, and since the rate of production of the disease is partiall) oamf odngustc.oalPmneiunmeros,niabutraptreosbabalrye theexcteusbsievre wsilhiiccah iiss cionmepxacreasbsle atnodthcaotalofnpoutreabcuonaldanItf, disepiennhdaelendt , utphoins ltahteterratfeacat t pwlahyischantheimdpuosrt culosis rate tries This is lower than m other indus seems to end with different we have a nodular tvpe similar to silicosis ' "As far as asbestos is concerned, we do tant role in predicting the relative danger of different environments Hence the need groups, and much more work must be done Ivefore we can talk dcfinitelv not know the whole stor> An autopsv re Iport of an individual rivmc ot asbestos^ for the evaluation of the quantity of dust m the industrial atmosphere is obvious "In general, it has bharmfulness of a quarts in direct proportion to For this reason, in atte the harmfulncss of a dusi icmalpocortmanpcoesittioona.sceUrtafiinas i tehraaltogtoicadletceormmipnoes atoorrui rao grerasoprhtictoanaalycsiosmbiIntedis c< such an analysis made b> graphic geology " Dr Bloomfield divpla indicated the percentage dust obtained in the van he had studied, as follow Romcki n ed)ri_l_li_n_g___d_u_st___(_br GRoracnkitedrciulltitningg dduusstt _(a: Brmasisnef)oun_d_r_y__d_u_s_t_________ DSluastet fmroilml druaswt m(Vilelsrminon< SAinlvtherrawcaitree cpooallishdiunsgt --dus BCietmumenint odusu scto-a-l---d--u-s-t----STlaaltce mmiillll dduustst(-V--e--r-m--o--n-t Marble cutting dust _ _ "It is evident," id D this table that rock dn the coal mining industry patioru in the granite c in brass foundries would class as judged by the p in the atmospheric dust Silica Dust iA* "A Dr. A . E. RusstU s. dust which produces th are inorganic dusts, arv offender. I have seen trades where silica <i i posure to dusts will pro lungs. A statement recc `Cement Bulletin' that 1 is not comparable to am "I have visited marble are apprenticed, going i a life work. I was an' to see this group of wc revealed that marble w to a smaller amount c workers. We found that moforetubfeibrcrousloissisth. anDirmn1 State Sanitarium itatrd marble workers as pan unless they had previou ite. We found no actr losis among this group dustry "Considering silica, i pene.ice that one of the plaints is that it short patient described it to that he had lost f is sec< hpalivceatetshethuesucaalsersssmervteh< child can not live ar uni 15 "In general, it has been found that the harmfulness of a quartz-containing dust is out being infected. They developed silicosis much more rapidly than those who did not dusty process one which is dust-free or which produces a relatively harmless dust in direct proportion to its quartz content. For this reason, in attempting to evaluate have this infection. "Silicosis is one of the foremost diseases. In the granite industry the surfacing ma chine, a heavy dust producing tool, has been the harmfulness of a dust, it is of the utmost importance to ascertain its exact mineralgi People all over the country are worked up over it. Many cases are coming before the replaced to some extent by the gang saw and the artificial abrasive wheel. These are ca! composition. It has been our experience that to determine accurately the exact min- juries. I believe in time they will have to subsidize hospitals in the larger cities and wet processes and have reduced the dust concentration associated with the surfacing eralogical composition of a dust one must resort to a combined chemical and petro in most manufacturing cities. Diagnostic service should be provided. This proposition of the stone to a figure well below the hygienic face limit. graphic analysis. It is our practice to have of submitting the evidence to lay juries is such an analysis made by an expert in petro dangerous." Control of Dusty Operations graphic geology." Dr. Russell then presented several slides "Isolation of the Hazardous Process: It Dr. Bloomfield displayed a table which ^showing the results of coal, slate, marble, is possible to isolate the dusty process in indicated the percentage of quartz content of ^cement, asbestos and granite dusts on lung many cases. This may consist merely m dust obtained in the various industries which tissues. confining the hazardous stages of manufac he had studied, as follow s: Rock drilling dust (bituminous coal Physical Examination of Employes ture to a separate building or room, thereby reducing the number of men exposed to the Grmaninitee) c..u..t..t.i.n...g.....d..u..s..t.......................................................................3554..20%% Necessary dust (and these men may be protected by Theodore Hatch said in part: "The masks), or it may mean complete isolation Romckined) ril.l..i.n..g......d...u..s..t......(.a..n...t.h...r..a..c..i.t..e.....c..o..a...l31.0% health hazard associated with exposure to from the workers in an enclosed space. Brass foundry dust......................................19.0% industrial dusts varies with the industry and "General Ventilation: In a lew instances DSluastte fmroilml druaswt m(Vilelrsminonctemreedntsplalaten)t..... 36..05%% Silverware polishing dust........................ 1.7% depends upon a number of factors, chief of which are the physical characteristics of of generalized dust production throughout the factory the use of general ventilation ABintuthmraincoitues ccooaall dduusts.t................................................................... 11..25%% those exposed, the chemical and physical properties of the dust, and its concentraton may prove satisfactory as a means of dust control. Under such conditions the in SCleamteenmt illdudsutst...(.V...e..r..m....o..n...t...g..r..e..e..n....s..l.a...t.e..)...., t1r.0a%ce Talc mill dust............................................... none in the atmosphere of the work places. "The evaluation of the hazard in a given troduction of large quantities of dust-free air serves to reduce the dust concentration Marble cutting dust..................................... none "It is evident," said Dr. Bloomfield, "from industrial plant must therefore be based upon a thorough investigation of the factory con by simple dilution. This method is used in certain mining operations, also for purposes this table that rock drilling occupations in the coal mining industry and certain occu ditions and a careful interpretation of the results. The investigation should include of removing heat and toxic gases as well as dust. In general it involves the installation pations in the granite cutting industry and in brass foundries would be in the hazardous physical examinations of the men and a study of morbidity and mortality statistics, of large fans and is expensive to operate This method should be looked upon as an class as judged by the proportions of quartz in the atmospheric dust." chemical examination of the dust, and deter minations of its physical properties such as adjunct to other methods of control rather than an independent method. Silica Dust the "Arch Offender" particle size. "Control of Dusts at the Origin: Effec "The most direct means of controlling the tive control of the dust at the point of gen Dr. A. E. Russell said in part: "The dust which produces the greatest damages hazard is by reducing the dust concentration to which the workers are exposed. The eration prevents it from reaching the breath ing zone -of the worker and hence offers a are inorganic dusts, and silica is the arch efficiency of the required dust control de positive means of reducing the dust hazard. offender. I have seen workers in dusty trades where silica is almost absent. E x fends upon the allowable concentration in ..ie atmo. phere, which in turn is determined It may be effected by the use of water or other liquids for capturing the dust or by posure to dusts will produce fibrosis of the lungs. A statement recently appeared in the by tlK toxicity of the dust and the tolerance of those exposed. The standard o f ,permis means of local exhaust ventilation. The use of water for laying dust is an old method `Cement Bulletin' that fibrosis in one case is not comparable to another. sible dustiness may be increased by careful selection of the men, by means of physical of control. It undoubtedly reduces the dust concentration, but investigations have shown "I have visited marble workers. The men are apprenticed, going into the industry for examination, and limiting their exposures through a system of rotation of employment. that it does not always give the high degree of protection required. Local exhaust ven a life work. I was anxious and very glad to see this group of workers. Dust counts It may be further increased by reducing the percentage of toxic material in the dust and tilation consists in removing the dust through a suction hood placed close to the point of revealed that marble workers are exposed to a smaller amount of dust than granite otherwise controlling its chemical and physi cal characteristics. generation. This method of control is widely used in industry and is most effective when workers. W e found that quite a number had "In the absence of definite knowledge, the applied to a stationary dust-producing ma more fibrosis than usual. Some had signs of tuberculosis. Dr. Rogers of Vermont safe course is to consider all dusts dangerous until proved innocent. chine or when it is attached to a moving tool, thus keeping it at a fixed distance from Stale Sanitarium stated that he did not have "The dusty processes encountered in in the point of dust origin. Its general appli marble workers as patients at his hospital dustry differ widely and exhibit a consider cation has been recognized and most states unless they had previously worked in gran ite. We found no active cases of tubercu able variation in the restrictions placed upon the design and operation of the devices for have incorporated specifications for the de sign of local exhaust systems in their in losis among this group in the marble in the control of the dust. No single method dustrial code." dustry. of contre' can be universally applied ; on the P rotective D evices for W orkers "Considering silica, it has been my ex perience that one of the first and last com contrary a number of methods have been developed to meet the needs of the dusty Prof. Philip Drinker said in part: "Pain ful as the cure may be, it consists of two per plaints is that it shortens the breath. A patient described it to me recently, sajing trades and the choice of method must be based upon a thorough study of local con fectly definite steps: (1) Medical examina tions of new employes and routine examina that he had lost his second wind and did not have the usual reserve. Tuberculosis com ditions The common methods follow: Substitution oj A on-hacardous Processes'. tions of all persons exposed to danger; us dust concentrations, and (2) reduction of plicates the cases in the various stages A child can not Inc around an adult case witli- I he silicon- hazard has been reduced in a number o' industrie- h\ substituting for the duIs'ltl coirnecernnit-r.aitrilo. n s breathed 1,1 fb,,> I w o.r k e r s to 16 "If dustiness can be controlled by local exhaust fans and dust-collecting equipment, protective devices such as respirators or positive pressure helmets have no place ex cept as emergency equipment. However, many processes like abrasive (sand or steel) blasting, paint and enamel spraying, porce lain manufacture, stone cutting, sand grind ing, and the like, will not. in all probability, be made reasonably dust free for some years to come. In work of this ty pe, respirators and other protective devices have an impor tant place. The safety man should under stand thoroughly what can be expected of protective devices and, above all, should be able to check and observe whether the work men arc getting the protection they require. "One secs occasionally statements to the effect that respirators have no place in in dustry because they filter out only large particles and let pass the small ones which arc always the more harmful. Against this is the indisputable fact that the dust catching efficiency of several makes of respirators exceeds 90% on silica dust with particles less than two microns. A careful measure ment of the size of dust particles entering and leaving respirators shows a slight but unimportant reduction in average size of the dust particles." Professor Drinker reviewed the specifica tions for respirators which have been for mulated by the U. S. Bureau of Mines and paid glowing tribute to the high caliber of its work and its importance to the safety movement. Also he outlined the require ments for testing sand blast helmets and paint spray masks. "The manufacture of protective equip ment," he said, "should be allowed all pos sible license in modifications and improve ments having to do with appearance, ob struction to vision, comfort, ruggedness and practicability of his equipment. If the manu facturer desires his product to be certified as to its performance under the conditions for which he designed and built it, the pro spective purchaser and safety engineer is equally desirous of knowing the performance data." Diicuaiion Discussion was withheld until all papers were read Chairman Greenburg then called upon various people for comment Follow ing this the meeting was thrown open for general discussion and then the original speakers called on for replies. Dr. Pancoast, pathologist, University of Pennsylvania, said in part "I have been interested in silicosis for a number of years. We have the very best way of finding out what changes are taking place in the lungs by x-rays. There can be no dispute to that question We also have one of the best wavs of determining the incapacity of the individual, but most of these examinations are not carried ont thoroughly and the in formation is not given The x-ray exam ination is only one small pai,, and lhat is something that is overlooked so frequently A physician who has little knowledge of the subject will present x-ray pictures--and diagnose silicosis as the cause ! It takes all of the ability of many witnesses who know something about the subject to counteract the few words he .may say. Many here know that. We must know the kind of dust, dust counts, chemical constituents of the dust, clinical aspect of the case, time of work, how long lie works each day, whether he is breathing the general atmosphere of the room or a more concentrated atmosphere. Previous occupation is often overlooked. All of these different sides to the question must be taken into consideration in every instance in which a man is charged with lack of capacity for work." Dr. McConnell, Metropolitan Life In surance Co., said : "Dr. Russell made a very important point in calling our atten tion to the necessity of having authority to decide cases This is a matter of consider able interest to the meeting, and much thought should be given to it." Mr. Cunningham said. "The whole sit uation has been presented very thoroughly. Two things have occurred to me: (1) Those stone cutters who have cut limestone for IS or 20 years and who have tubercu losis, in each case have cut sandstone previ ously. Whether a short exposure a long time ago is important 20 years later is im portant. (2) Examination of workers who have been exposed simultaneously to silica and alkali. Reports have been made show ing silicosis may develop rapidly. I am in terested in the presentation of the situation regarding the control of dust because it is the real problem ahead of us." Dr. Lloyd, U. S. Bureau of Standards, said : "Dr. Drinker told us how they test the respirator and pointed out the impracti cability of using positive air pressure as a dust eliminator. A definite opinion is de sired as to what type of respirator is ade quate under bad dust conditions and within acceptable operating limits for protecting a man." Dr. Drinker: "I certainly do not con sider respirators adequate under such cir cumstances. Supposing you have a dusty atmosphere of, say, 50,000,000 count and you want to reduce it to 20,000,000. If your respirator is 90% efficient it would get the dust concentration down to 5,000,000, but eight hours a day constant use will be ob jectionable. In jobs in places like foundries, mines, sand blasts, etc., the exposure is not contin"ous. In such cases the respirator is not worn continuously." Dr. Knutsen, Wisconsin Industrial Com mission, said: "Two or three of the speak ers made mention of the decision of claims which are made as the result of men be coming incapacitated m working in dusty occupations. , " 1his, to me, has been one oi the most October 22, 1932 interesting sections I have attended in over 10 years of Safety Council meetings The problem of silicosis and tuberculosis has been before us in Wisconsin since 1917, because of the fact that at that time our compensa tion law was amended providing compensa tion benefits foi any disease or disabilityresulting from an occupation. I appreciate that one or two states have such provisions I suggest one way of deciding a case is to have compensation laws amended covering all diseases of occupations so that claims may be decided by the industrial commission rather than by juries as the result of civil claims being filed. "I will relate briefly difficulties we have. I do not wish to make a statement reflecting on the medical profession. The difficulty is this: Oftentimes a claim is presented to us for compensation by some individual because of a disability allegedly resulting from sili cosis. In many of those cases we have mem bers of the medical profession testify in behalf of the clients, who we personally are satisfied are not specialists or competent along those particular lines. The discourag ing thing to us is that in hearing the evi dence we have men before us who have specialized for years in lung diseases, men who are engaged in private practice and are at the head of tubercular institutions, testify ing one group on one side, that the results of physical findings and x-rays show that the patient is disabled as a result of silicosis. Others equally qualified testify to the con trary. We have had some of these cases when we heard testimony and the individual didn't have long to live. We withheld our decision until the individual passed away and suggested an autopsy. We can not force an autopsy, but we are privileged to withhold our decision. After the autopsy, these two groups of doctors take specime examining them microscopically, and we hear tnem tak ing the same position that they had in the first hearing. That. I want to say, is mightydiscouraging." Dr. Roach, compensation commissioner for the state of New Jersey, said in part: "I am very much interested in the subject, because silicosis is a thing that we are verymuch concerned about in New Jersey at the present time. I might say that we have some experience in compensation cases m the state parallel to that described by Com missioner Knutsen from Wisconsin. It doesn't require much evidence to prove that certain quantities of silica are harmful to the human system After an exposure continu ous over a period of time long enough, per manent physical damage is bound to result, maybe to the point of the extinction of 'he individual. There are certain things that I am very much concerned about in connection with this subject of dust. To find some workable productive device that will safe guard the men who are exposed in 60 or 7C different industries to silica dust It is n'-t eass It mat be that in the laboratory e'