Document aDy81EQGMXM7xG2Xn5EjQ1JGy

FILE NAME Insurance Industry INS DATE 1940 DOC INS013 DOCUMENT DESCRIPTION Published Conference Presentations - Underwriting Aspects of the Industrial Dust Hazard Dr. Lanza & Following Discussion " PROCEEDINGS OF THE " THIRTIETH ANNUAL MEETING OF THE ' ry MEDICAL SECTION OF THE AMERICAN LIFE CONVENTION 2 1940 OFFICERS - MEDICAL SECTION Chairman A. J. ROBINSON Medical Director Connecticut General Life Insurance Company Hartford Connecticut : Chairman W. F. BLACKFORD Medical Director Commonwealth Life Insurance Com- pany Louisville Kentucky : Secretary B. BYKD Medical Director National Life & Accident Insurance Company Nashville Tennessee Member of Board of Managers T. H. Dickson Medical Director Minnesota Mutual Life Insur ance Company St. Paul Minnesota Moral Program DR RT ESTON Medical Directo Moral Life Assurance Go of Canada PREPEAT PREPEAT PREPEAT PREPEAT PREPEAT PREPEAT PREPEAT OF THE LIBRAY LIBRARY LIBRARY LIBRARY LIBRARY LIBRARY PREPEAT OF THE LIBRARY ew tte oe at te te Seaee ewe > : wae 9 e te. TOT ST, ! Bae) aPethre wes ee Nem hes ea 6 ye 4) ensete me + rd . ae i ' t t t PTE AS CD ee Noun weve mr ae mE rete ere mg ee ee em wee we ee PE aR TREES ere FL i I i hid re oom te ae | : ast amy bop AG ae re Underwriting Aspects of the Industrial Dust Hazard A. J. LANZA M. D. Assistant Medical Director and R. J. VANE Statistical Bureau Metropolitan Life Insurance Company New York N. LR knowledge of health hazards resulting from exposure to various kinds of dust in industrial occupations is based on observations and clinical studies of workmen exposed to these dusts and upon noting the results of the action of these same dusts upon experimental animals The former method goes back for centuries and the earliest conceptions of the harmful properties of dust were based on first hand observation Many of these conceptions were erroneous It is only in the past twenty years that anything like a comprehensive knowledge of dust diseases has been attain - e dude first to the perfection of the ray as a means of diagnosis and the development of successful laboratory technique for conducting tests on experimental animals Now we have arrived at a point where intensive studies both clinical and experimental conducted in this country and in other countries have resulted in a crystalization of our ideas In the English speaking world the outstanding contributions to our knowledge have come from the South African Institute for Medical Research and the Miner's Phthisis Prevention Committee in Johannesburg from various official agencies in England and Australia in Ontario Canada and in this country especially the United States Public Health Service the United States Bureau of Mines and the Saranac Laboratory In presenting this discussion of industrial dusts their effects on workmen exposed to them and the bearing that this subject has on 175 ge ze Setter eM amma > Be tet Wticoaatilnmikcleee TD . TOT i % PYAR 5 F, PEO BTIFERS SOT ed 08 ok oe ES t-te Pr 23 SEPnate ie ie LAATeso TeEST AN TPO ASTOR LPR ey EYE cw ne eee Me GET . Eke to uf ELwe Ce we * i : we oa eo, i ' OR alts KA ys go % ? 02, : - watt S SPe E eat ree name teoe eo os. SS wed 2 = a aes ee Pt ate ae eeeyieecenesas Pan wes thane Wig we Silos are Be Se a ate Sree* ee ee ew Orie isan ied er ae ee pen te Bee ee k ran S = 176 UNDERWRITING ASPECTS - DUST HAZARD life insurance underwriting Mr. Vane and the writer have attempted to summarize what should be the insurance attitude based on the present state of our knowledge Briefly the present concept regarding industrial dust hazards is as follows Organic dusts of which the dust arising in textile operations is an example do not cause any specific pulmonary disease There is no clinical or experimental evidence to the contrary Coal which is an organic substance is considered in connection with mineral dusts Organic dusts at times may cause an allergic reaction and also irritation of the upper air passages They do not cause protracted disability or death In this classification may be included cotton wool silk sugar flour starch wood tobacco and leather It is true that some occupations in which is involved exposure to organic dusts manifest a tuberculosis mortality rate higher than the average Formerly it was thought that this undue prevalence of tuberculosis was due to the occupational dusts but the dust studies of recent years have demonstrated that mostly organic particles are too large to penetrate to the pulmonary tissue and when they do they are absorbed without producing any specific inflammatory reaction Nor is much credence given nowadays to the idea that organic dust particles convey tubercle bacilli to the lungs and thus cause tuberculosis METALLIC DUSTS Here the situation is not unlike that of organic dusts The preval ence of pulmonary disease among workers in certain occupations exposed to metallic dusts gave rise to the theory that metallic dust was a fruitful source of tuberculosis Such diseases as grinder's rot were recognized clinically long before the era of modern diagnosis and laboratory research Metallic particles in the form of fumes may cause such reactions as zinc chills or brass founder's ague which are more in the nature of an allergic reaction The pulmonary disease which afflicts grinders and buffers is silicosis and not in any way a result of exposure to metallic dust Metallic dust particles are mostly large and heavy that is comparatively speaking consequently they do not penetrate to the lung in mary instances and when they do they are either absorbed or remain fixed and inert in the tissues From an underwrit- ing standpoint then the hazard of metal dust is the hazard of such silica dust as may be associated with it COAL For many years there has been a belief that coal miners had less tuberculosis than the average for wage earners and on the other hand i ene voN pUtGs name we Yee _* eGo, Pe r ee, ant yee 9 = += ee TS 2 Can Dt lee ' ye wom EP en tL A. J. LANZA M.D. & R. J. VANE 177 miner's asthma has been recognized miners Here again recent studies considerable extent as an have occupational clarified the disease of coal situation to a Bituminous or soft coal miners do not have an occupational ' pneumoconiosis of a disabling quality Their lungs become pigmented from coal dust but they do not develop a true fibrosis For anthracite . miners the picture is quite different and the reason is that anthracite mining includes exposure not only to coal dust but also to silica Dis- abling miner's asthma was shown by the United States Public Health Service study of 1935 to be a type of silicosis to which the term anthraco is properly applied Anthracite seams are often found in country rock which contains a considerable amount of free silica and as in other silica dust exposures the development of pulmonary fibrosis was found to be proportionate to the amount of silica in the coal dust and the length of exposure The incidence of tuberculosis among anthracite miners is very high Clinical pulmonary tuberculosis : was found in 15 per cent of those with early anthraco and in 43 per cent of those wb wb advanced anthraco Service of twenty to twenty years was associated with a tuberculouspiswarradtse of 14 per cent among regular miners and 37 per cent among those with a number of years as rock workers Animal experimentation with both bituminous and anthracite coal dust free from associated silica produced no specific reaction SILICEOUS MINERALS There is no evidence that siliceous minerals produce any pul- 1 monary disease Gardner at the Saranac Laboratory tested upon ani- mals such substances as diamond aluminum oxide rutile marble gyp- sum galena chalcopyrite iron sulphide zinc sulphate fluorite and dolomite The sulphides and dolomite proved toxic but this effect is outside of our present discussion siliceous minerals proved in- active in animals and there is no clinical evidence of specific disease among workers exposed to this type of dust if Ft gh Be m? EFI tesSb BRP oa ie an peu = ne _ wy Sane eee 78 pra ae vue - S Korner NY roe 4% b+. . Pe Lite ionon ata RS ee A Re TINE MIT ROR ARTIFICIAL ABRASIVES Experiments with artificial abrasives demonstrated the incorrect- ' ness of earlier ideas that dust caused injury to the lungs proportionate to the hardness and sharpness of the particles I can remember a time when it was generally believed that the injurious qualities of a dust de- pended upon the hardness of the dust and the sharpness of the par- ticles It was not until we had pursued our studies in dust counts and dust experimentation that we realized that when you were talking of me oe e yothermn o s og IAF Mer path eh h S10 8 LSeT Fates Bn 27Hon, y : "ue of dhe ae eG gh thee wan hea SPAMmf ti HS ee 48 eae ae yh 4 atte meena wptont -;-. a o* Teton 5 Soot eS egme 178 UNDERWRITING ASPECTS - DUST HAZARD dust particles of one to two and three microns in their largest diameter that those particles had no physical characteristics in the in which we apply them ordinary sense Artificial abrasives are among the hardest substances known Neither silicon carbide nor aluminum oxide duced any reaction resembling silicosis in experimental animals pro- workmen exposed to these dusts show nor do any clinical symptoms or ray appearances suggestive of silicosis SILICATES A considerable number of silicate dusts have been studied and their effects upon experimental animals both by inhalation and tion noted They produce little or no reaction in the injec- what little reaction some of them do body tissues and produce does not tend to progress An exception should be noted here regarding asbestos which is con- sidered separately Nor is occupational exposure to silicate dusts such clinical picture of disability and death as is afcocuonmdpainniesidlicbay daunsty exposures The Public Health Service studied some talc mines in 1935 Only 65 men were exposed Tuberculosis morbidity and mortality rates were very high in the county where the mines were located and the dust exposure was exceedingly severe running into hundreds of millions of particles Eight men showed advanced pneumoconiosis but tuberculosis was also present in most of them It is conceivable that exposure to tremendous quantities of any mineral dust regardless of content might so overwhelm the lungs that they could not deal with the invading substance infection would follow with Irritation inflammation and probably disability in proportion Such isolated instances do not invalidate the conclusions stated in the previous paragraph ASBESTOS Asbestos is the only dust of combined silica which is known to cause a definite pulmonary fibrosis which may result in disability and death Let me make that point clear When we talk of silicosis and the types of dust that produce silicosis we mean dusts that contain silica in a free or uncombined state SiO When the silica is in the form of silicon carbide or magnesium silicate or iron silicate that is what we mean by combined silica The combined silicate dusts as I have just mentioned do not produce any pulmonary disease with one exception and that one exception is asbestos which is a hydrated magnesium silicate mixture with little iron in it Most of the asbestos fabricated in the United States comes from the mines in " ~ ee ae Mae are we eT aE TF cal act silk los else the othe up caus the insura the ca people varianc Se aaah aalead oe ott ~ Ca ae - AJ AJ LANZA M.D. & R. J. VANE 17179 9 Quebec Asbestosis however is not found among asbestos miners most of whom work in open quarries or pits nor among men engaged in milling operations whereby the asbestos is prepared for shipment and bagged but among workers in fabricating plants Fabrication you will understand being in the nature of a textile process Only recently has an explanation been offered for this anomaly It would appear that not only is asbestos an exception in that it differs from other silicate dusts in its ability to cause structural changes in the lungs but its action appears to be mechanical and not chemical like the action of silica If asbestos is crushed to fine particles it will not cause asbes tosis in experimental animals nor will asbesto produce any reaction elsewhere than in the lungs If its action were in the nature of silica the effect would be more pronounced with smaller particle sizes In other words Gardner established that the intensity of a silica reaction upon animals depended upon the smallness of the silica particles because to sum it up briefly the finer the silica particles the greater is the surface exposure which acts upon the pulmonary tissue Asbestos parucles below a certain size do not produce any effect in experimental animals Furthermore you can produce a silicotic reaction the typical silicotic nodule in any organ by injecting prepared silica You can get silicosis of the liver or of the spleen or elsewhere But you cannot produce any reaction in animals with asbestos anywhere except in the lungs and then only if your particles are sufficiently large Consequently Gardner concludes that the relatively long spicules of asbestos produce their effect because the Jungs are never at rest and the constant movement provokes the fibrous reaction Like silicosis asbestosis develops slowly presenting the charac- teristic symptom of shortness of breath The number of cases of asbestosis that have come to autopsy is small but there are several cases on record in which death was due entirely to the asbestos and not to any associated infection or other condition There does not seem to be any pronounced tendency to tuberculosis in asbestosis but most of the fatal cases have been complicated by other disease such as cancer and diabetes so that the extent to which the asbestosis was . responsible for death is not clear I made a rather exhaustive study a few years ago of all the insurance certificates that I could find in which asbestos was given as the cause of death and then followed up the previous history of these people and got their medical certificates when they were on disability The diagnosis given on the disability certificates was usually so at variance with the diagnosis given on the death certificates often by are el ae Re . Roa 2pemahey el, ay rarety Spe nae gf FE CE OM Ta et ae oe _ ieB >O abe t Ee en ane Teen af eee lors rs ppm per tf tte Met ore Or ot ier gt eka er e ce Sete ne re Be5 rere t may ates tan maTES& py wale ae gy, AE ALE 0 sete, Done A abate very a 180 UNDERWRITING ASPECTS - DUST HAZARD the same physician that it was impossible to come to any definite conclusion and say this man died of asbestosis when his previous disability certificates showed that he had myocarditis or high blood pressure or cancer or diabetes or pulmonary tuberculosis The pathology and ray appearance of asbestosis are entirely different from silicosis and in the absence of a definite history of ex- posure over a considerable period of time to asbestos dust the diag- nosis is difficult A great deal of success has been attained in controlling dusts in the plants where asbestos is fabricated so that it is not likely that asbestosis will ever become an important industrial disease as far as the number of cases is concerned The scarcity of clinical data on asbestosis makes the prognosis doubtful We have had a small group of cases under observation for have about ten ther theere were originally I think some sixty odd men in this group and we still have fifty of them where we can get at thte his am nd some of these show a definite but slow progression as far as can be judged from the ray films However what the outcome may be remains to be seen These men are all working and show no signs of any disability In the meantime the plants have been cleaned men are not exposed now to inordinate quantities so it is difficult to say what would have been the up so that of asbestos progress of these dust their disease had their working conditions remained the same SILICOSIS It may be said that there is a very general accord among the leading investigators and research authorities in the opinions and conclusions presented at the international conferences on silicosis Johannesburg August 1930. Geneva August and September 1938. Such differences of opinion as may be expressed from time to time do not seriously affect the general agreement on the basic factors affecting the cause incidence effects and prognosis of silicosis The effect of silica upon the lungs depends on the nature and extent of exposure That is to say upon the quantity of dust in the air breathed by workmen the amount of free or uncombined silica in the dust the size of the dust particles the presence of other substances in the dust which may modify the action of silica and the length of time or duration of exposure The individual himself must also be considered Previously existing disease of the lungs especially a tubercle infection will influence his reaction to inhaled silica There may be other phases of susceptibility about which we know little or A. J. LANZA M.D. & R. J. VANE 181 nothing but in the main it may be stated that individual susceptibility to the action of silica dust is an acquired rather than a congenital condition In industry we find different types of silica bazards The severity of a silica hazard is estimated on the amount of dust in the air and this is expressed in millions of particles per cubic foot The particles counted are those under ten microns in size though the present opinion is that the particles between half a micron and three microns are mostly responsible for causing the disease MTC Exposure to excessive quantities of pure silica dust that is where the dust count is in the hundred of millions of particles per cubic foot ay is now rare Isolated instances may be found as in the case of a Rae sandblaster improperly protected Such exposure produces a severe ag rea type of silicosis in upwards of five years even sooner in extreme cases With such extensive silica damage to the lungs tubercle infection is PN almost inevitable though cases will be seen occasionalthlayt proceed to a fatal termination without infection ae Exposure to amounts of silica dust where the particle counts are in excess of ten million does not occur frequently at the present time eee though it is only in the last few years that silica industries have en- re deavored to cope with their dust problem and effectively reduce the amount Such exposures produce definite disease in from eight or ten LRM to twenty or more years in proportion to the actual quantity of dust The incidence of tuberculosis is high and of those who die of their pulmonary condition 75 per cent are tuberculous This does not ~~ ety mean that 75 per cent of silicotics have tuberculosis but of those ree SHY whose damage to their lungs is sufficient to cause their death that is where death is due primarily to silicosis 75 per cent of them will ETS have tuberculosis also Aw It is also possible to find degrees of silica exposure which while oI producing definite silicosis evident on rays will not produce dis ase ability or death in an average working etime Mortality statistics mer are not broken down by industry to an extent sufficient to make avail- able definite figures by degree of exposure We must rely then on the clinical results obtained in industrial investigations which are con- Owe clusive enough for those industries studied Our own impression is | Ben that even where the silica hazard is of a mild type the incidence of tuberculosis will be higher than the average It has been stated that UPI where silica dust contains caustic alkalies also the action of the silica is intensified very considerably The evidence here is meager Other en pa +e : oo re - feo PET ~ a oo ~ Ay 7 te _ e De o eee ee tet OE 4 ele poe poreees, Veaare Sehr Nap we ad TE aE) . a ORAS baoged oe BML ares a, arene , 182 UNDERWRITING ASPECTS - DUST HAZARD substances apparently have some inhibiting effect upon the action of silica affecting the pathological as well as the clinical picture PROGNOSIS The prognosis is fair for a silicotic whose lungs are not extensively damaged and who is free of infection Such persons have an increased susceptibility to infection and if brought into intimate contact with a case of tuberculosis are very apt to become tuberculous also The outlook for the tuberculo is poor Many cases are essentially chronic and may live for years Others show rapid progression and : die in from one to two years after their infection becomes active The importance of tuberculous infection among persons exposed to silica dust brings up a very important underwriting consideration that is | where the worker in a silica occupation is in contact in his home with an open case of tuberculosis Insurance in such cases should be declined The question is frequently asked whether men who had worked in silica dust at one time but later changed to a job in which there was no exposure to silica might be considered standard risks for life insurance if they passed the usual insurance physical examination While there are no insurance statistics to prove the point one way or the other there is every reason to believe that a group of such men will not give a standard mortality The usual type of physical ex- amination will not detect silicosis The only way to be sure is to secure rays of the lungs of such applicants and have them inter- preted by some one who has specialized in reading films of this kind : Silicosis is gradually coming under control The aggravated cases seen twenty years ago are rarely seen now and the clinical picture | has changed with the progress of dust control measures The trend is towards a lessened incidence of new cases of silicosis This improve- ment depends upon the maintenance of constant vigilance in detecting unsuspected hazards and in supervising the efficiency of dust control methods after they have been put into effect It cannot be expected that this improvement will be reflected in insurance mortality until } a considerable period of time has elapsed The conclusion seems warranted from clinical and laboratory experience then that the only dusts which of themselves might have sufficient effect on the mortality of workers exposed to them so 1 great as to require an extra premium charge for life insurance are silica and possibly asbestos Life insurance men naturally will turn to mortality statistics for confirmation of a finding so at variance with the common belief long pos Cer A. J. LANZA M.D. & R. J. VANE 183 held that exposure to all kinds of dusts is productive of a high incidence of respiratory tuberculosis To the layman it seems only reason able to suppose that the difficulty in breathing he experiences when exposed to large quantities of dust must in some way affect his health and that filling the lungs with foreign particles must have injurious effects on them The writings of eminent students of occupational mortality statistics have served to strengthen this belief Nearly all such statistics show the mortality from respiratory tuberculosis among workers exposed to a wide variety of dusts to be well above the average for all workers included in the study But when these figures are refined so far as is practicable to make allowance for factors other than dust which may influence the mortality from tuberculosis of men employed in these occupations the importance of many dusts as causative factors becomes less evident There is a surprisingly large number of factors other than dust any one of which may be responsible for the high mortality from tuberculosis among men in dusty trades Some dusty occupations are carried on by men recruited from the lower income classes among whom it is now known that apart entirely from exposure to a specific occupational hazard the death rate from tuberculosis is considerably higher than among persons in the higher income groups The selection of certain kinds of work by the less robust workers is reflected in the high mortality from tuberculosis of men in those occupations Racial and nationality groups tend to enter certain occupations with the result that the peculiar susceptibility or relative immunity to tuberculosis of these stocks colors the mortality picture of men in such occupations These are but a few of the many circumstances for which allowance must be made before conclusions can be drawn as to whether a particular dust is or is not the responsible agent in the high mortality found among men in a dusty trade Unfortunately there is for the United States no considerable body of mortality statistics sufficiently detailed to permit of evaluating separately some of even the most important conditions affecting the mortality of men in specific occupations Perhaps the best statistical demonstration of the effect of different types of dusts on mortality from tuberculosis is supplied by two British authorities Dr. Edgar L. Collis and G. Udney Yule These authors selected for study from the occupations reported upon in the Registrar General of England and Wales report on Occupational Mortality covering the years 1921-1923 two groups of occupati-ononse exposed to silica dust and the other to silica inorganic dust The groups were so chosen that each had as far as possible the same amount of dust exposure physical effort zz Eede > . ee eee e r ak e etre res $ ae ee roa Age eashat el > 2 F ee Pe TREO Te Yon .te RUT intyead oe weVine of Me sah t ett a BRP A us de detnboled. ante gets. t Srey edt ,- SA abheg Be ve i viiefi 1 e 184 UNDERWRITING ASPECTS - DUST HAZARD exposure to beat or to weather or any underground environment Part of the authors comment on the results tuberculosis is quoted as regards respiratory For all ages 20 to 65 the Comparative Mortality figure this figure is defined as the number of deaths that would have occurred in the Standard Population at the rates ruling in the occupation of the Silica Group is no less than 592.2 against 163.5 for the Standard Population i e the mortality is more than and a half times the normal For the Silica Group the Ctohrme-e parative Mortality Figure although actually slightly higher than normal at first sight hardly seems to differ significantly from the normal nor would one's judgment be much affected if instead of making comparison with the Standard used the Social Population one had Comparative MortGarloiutpys fiIgIuIresandareIV159f.o8r awnhdich164th.e2 reBsuptecttihvee summary figures conceal interesting changes with age A glance at the figures shown on Table 4 of their study shows that in gtrheeatSeirlitcahanGruonuipty tehveenraitniothoef lomwoersttality to the normal though ow group rapidly increases as age advances In the Silica Group the comparative tality is actually below normal up to age 35 it rises just abmoovre- normal in the following group but at ages over 45 it is conspicuously above normal The facts regarding tuberculosis were not published in this for each of the six silica report oo, sere We have however occupational determined classes included in the study Registrar General that by reference to the Report of the each of the silica occupations had over twice tenps= the expected number of deaths The extraordinarily high ratio of 1.150 per cent was recorded for tin and copper miners while sandstone masons cutters and dressers had a ratio of 441 other hand only the limestone per cent On the masons cutters and dressers of the five occupations considered in the silica group exhibited 191 per cent a high ratio ac PE Like the English tin and copper miners American American metal miners LW. exposed to a seriousserious silica hazard and have an inordinate mortality fraorme respiratory tuberculosis as will be seen by reference to the Ee table In this table are given the ratios of actual following from tuberculosis for a number of to expected deaths SN occupations exposed to dust and re- ported upon in the Joint Occupation Study 1928 1928 and in the Occupa- 0 OO tional Study 1937 both published by the Actuarial and the Association of Life Insurance Medical DirecStoocrisetIyn otfheAmpeerriicoda et 1915-1926 the number of deaths from respiratory tuberculosis among me of . the reco amc NU Com Stud the A OQ Mine ' Met Co G Irc Le Coal All Pe 0 Stone ( Gran Othe Chipper Bulars Grinders Upholste Cotton ? FS Wochen EXC Data no Substanc Roblen business Three d Ratio 1 basic tak and fem iw wee et oF, Ty ee PS oP se TO ee ee wee 7 m i ca inetd - _ ad S's 4 So Te ve foo. A. J. LANZA M.D. & R. J. VANE 185 metal miners was over eight times the number expected on the basis of death rates by ages prevailing among Standard Ordinary lives in the same years In the later study covering the years 1925 to the ratios were even higher over 11 times as many deaths 1w9e3r5e recorded for metal miners as were expected on the basis of death rates among Standard lives in these years NUMBER OF DEATHS AND RATIO PER CENT OF ACTUAL TO EXPECTED DEATHS FROM TUBERCULOSIS OF THE RESPIRATORY SYSTEM Ordinary Department Experience of American Life Insurance Companies Compiled from Joint Occupation Study 1928 and Occupational Study 1937 both published by the Acturial Society of America and the Association of Life Insurance Medical Directors WHITE LIVES Occupation 1915-1926 Actual Ratio Actual Mine Underground Metal Mines . Deaths 48 Copper mines ow 24 Gold and Silver mines 9 Iron mines ar | Lead and Zinc mines veer 11 Coal Mines To Expected 815 913 804 200 1833 All mines ce aaees .125 157 Pennsylvania Pennsylvania mostly anthracite # . Other localities bituminous @ . Stone Cutters Granite and Sandstone Marble and limestone tetas ee nee 16 3 Other and not specified stones * Chippers of Metal except shipbuilding 8 Buffers and Polishers of Metals 10 _ Grinders of Metalst __ 7 Upholsterers sete eee cena 16 Cotton Mill Operatives males * ou. a Excluding carders and combers Woolen Mil Operatives males _. bd Excluding carders and combers 976 294 615 147 710 225 . 1925-1935 Actual Ratio Actual Deathst To Expected 52 1113 29 1381 11 940 12 857 I an 135 115 ZO 35 10 16 16 * 5 bd 14 10 288 334 161 2639 1053 1560 1667 . 154 : 243 200 Data not available Substandard business only studied woelen mill operatives for which business are included except for grinders of metals cotton mill and occupations both Standard and Substandard #Three deaths from tuberculosis in approximately 1,200 life years of exposure Ratio reported in text Expected deaths for this occupation calculated from basic table for males only for other occupations from basic tables for males and females combined BSS Fated pon aa oo x pee et | Seer eee eT: ES RS SeBB kae =F gee EP PRS LEN eae 2 ass = ns a os a eh ; ateath * a : a . - t : ; oe } ree : : af 7 7 . Ste ad inane Se ake im Tee . oT - STSE ET 7 ". >, Se ae ara, Te athe RP oe ae RES Salo? =n ee Eee iy Aes ~ * ee EY men 6 alld St IPHyt HEINPW Se s eth as bow ae aohars keds UNDERWRITING ASPECTS . DUST HAZARD While the actual number of deaths for each ing class was rather small in both separate metal min- ratios are investigations and consequently the subject to a large margin of error nevertheless it is interest- ing to observe that they were quite uniformly high for gold and silver miners and lead and zinc copper miners miners The situation as regards iron miners is interesting because it thought for a long time that they had little or no was More recent studies show that there is actually a moedxeporsautree dteogrseieliocaf silica hazard which produces silicosis in upwards of twenty years However in both insurance studies there were too few deaths from respiratory tuberculosis to permit definite quantitative conclusions therefrom In the later study there were 12 deaths from which was over eight and half times the expected tuberculosis A great many workers in mining occupations it must be borne in mind are common laborers among whom we should higher mortality from tuberculosis than expect a much policyholders From the limited data availaabmloengforStunasnkdialrlded Owrodriknearrsy from these studies it would appear that the tuberculosis death rate for this class of workers runs between two and three times the for Standard Ordinary business Thus it is clear rate that even when allowance is made for the important factor of economic class the death rates for the metal miners are extremely high Coal miners in different sections of the country present an interest- ing contrast Among the bituminous miners exclusive of the Pennsyl vania miners the mortality from tuberculosis was over one and one- half times that of Standard Ordinary lives a low ratio for this type of worker Pennsylvania miners on the other hand most of whom dust were employed in the anthracite field had a very high ratio of actual to expected deaths well over 300 per cent Anthracite miners as have stated are exposed to an appreciable amount of silica we which accounts for their relatively unfavorable position , No dusty trade has received more careful study in the United States than that of granite cutting Long recognized as a dangerous trade it has been found time and again to take a heavy toll in deaths from tuberculosis The amount of free silica in the dust breathed by these workers is very large In the years 1925 to 1935 the from tuberculosis mortality among granite and sandstone cutters was the highest recorded for any of the groups of insured lives studied There were more than twenty times as many deaths from tuberculosis as granite expected whereas in the earlier years there were nearly ten times as many deaths as expected based on a small exposure Marble and lime- stone cutters did not show anything like as high a ratio as the ord a na me be > er so AV re tees fae RES. a a mI MST mw . ali See. ore + of oa nee OFS. Near o> A oe Sey A. J. LANZA M.D. & R. J. VANE 187 and sandstone cutters There were ten deaths where one was expected in the years 1925 to 1935 It can be but regretted that there are so few mortality statistics for occupations exposed to dusts other than silica Grinders of metals most of whom for many years have been using composition wheels in place of the old sandstone wheels and consequently have had little or no exposure to free silica experienced a relatively low extra mor- tality from tuberculosis in both studies based however on a small exposure An interesting point to be noted here is that this also offers exposure to metallic dust It would appear that noecictuhpeartitohne dust from the composition wheels nor the metal dust has produced excessively high death rates from tuberculosis Buffers and polishers a somewhat similar group also appear to have a low extra from tuberculosis in the years 1915 to 1926 mortality Cement lime and artificial stone workers were reported upon in both the Joint Occupation Study and the Occupational Study but the number of deaths from tuberculosis was in each instance less than the number required for separate tabulation This fact in itself is significant although it does not mean necessarily that the death rate from tuberculosis was below the average Nevertheless from the facts presented in these studies it is quite evident that the tuberculosis . death rate for this occupational class was comparatively low Three groups of male workers exposed to organic dusts are in- cluded in the upho-luspthoelsrteerrerss cotton mill operatives and woolen mill operatives The ratios for all of these classes run about 200 per cent based on small exposures It must be admitted that these occupational mortality statistics are meagre and do not permit of very definite conclusions rezarding the effects of specific dusts So far as they go they fully substantiate clinical and laboratory findings regarding the injurious character of silica dust The death rates from respiratory tuberculosis for men in occupations where there is a serious exposure to silica dust are so high as to leave no room for doubt that silica is the offending agency Contrary to clinical and laboratory findings however the mortality statistics presented by Callis and Yule suggest that long continued exposure to siliceous inorganic dust has an injurious effect on the lungs as is indicated by the higher mortality from tuberculosis among exposed workers after age 45. About all that can be said on this point from the limited American life insurance company experience is that the tuberculosis death rates for grinders metal polishers and buffers who are exposed to inorganic dusts most of which do not wef if es ; : 4 t we e awr' eearrns s eeageoewrtey we sym RI ee e Vai Lb fawtenlan. ups feb aah fees hh bh ak or sbiresleryoars ee 188 UNDERWRITING ASPECTS - DUST HAZARD contain a large percentage of silica are not high having in mind the economic status of these workers as compared with the average ordi- nary policyholder Lime cement and artificial stone quite favorable mortality The workers had a of marble and limestone very high ratio for the small group cutters however may be suggestive of some untoward influence Dr. L. U. Gardner at Saranac Lake found that animals dusted with marble dust by inhalation developed little taucbteirocnulobsuits bTehcaemeinctreemapsoerdarily more susceptible to infection wirteh- stand that susceptibility was not marked I under- that is nobody that else has been able to duplicate that experiment dusting animals with marble dust increases their ibility to tuberculosis for a short time suscept- The three occupations in which there is had from to two and half times theexnpuomsbureer toof otrugbaenricculdoussits deaths expected Even allowingalowing for the economic position of these groups as compared with Ordinary Ordinary policyholders generally the mor- tality is high It is difficult to see in the light of present clinical knowl- edge how it is possible to account for the score of damage to excess the lungs caused by such dust mortality on the Mortality findings then are still not in complete harmony with clinical and laboratory findings But from a practical standpoint it may be said that the only dust which of underwriting itself affect the total mortality by increasing the incidence of might so as to require an extra premium charge for life insurance istufbreerecusliolsicias We have no mortality data for asbestos workers but it may well be that exposure to asbestos dust in large quantities will also be found to produce a high mortality Chairman Bender Discussion of this most excellent be opened by Mr. Morris Pitler Statistician Research Sectipoanpeorf wtihlel Mutual Life Insurance Company of New York Mr. Pitler has tributed a respectable number of papers to the Home Office cLoifne- Underwriters Association dealing particularly with the of hazardous industries and writing occupations He has served as Chairman of the Occupational Committee of this organization and is Editor of the Suggested Reading List for Underwriters Mart . prPeistelenrt Mr. Pitler Before proceeding to a discussion of Dr. Lanza's paper I would like to take this pleasure at being here with opportunity to express my great of this beautiful hotel you among the beautiful surroundings I wish to personally thank Dr. Dickson your Program Chairman for making my visit here possible by his invi- tation to take part in your proceedings ae cae epmy nes cera Te ns en ges rere sr wpe per : _ | Dis Dis SQ We the gen any dus concent that du composi to ind almost ; cess mu amount harmful Tru that the damage sibly as sources less it d ment by authors and perl Discussion Underwriting Aspects of F- the Industrial Dust Hazard t: 1- MORRIS PITLER Statistician Research Section Mutual Life Insurance Company of New York st New York N. is se 1- ie HE discussion to which we have just listen - e andd I might say Dr. Lanza listened with great pleasure up to a somewhat startling conclusion h g We in the life insurance business have for many years shared , the general concept that exposure to excessive concentrations dust S any dust must affect adversely the health of those exposed to such 3 concentrations for any appreciable length of time We believed too e that dusts varied in danger according to their character or chemical 2 composition And in the statistics of our mortality studies we seemed to find ample proof for these beliefs The called dusty trades almost always showed higher than average mortality ratios with ex- 1 cess mortality from tuberculosis of the lungs and the differences in rp amount of excess mortality indicated that some dusts were more : harmful than others cw ca z True that for a number of years now we have repeatedly heard 1 2 that there is little or no clinical or experimental evidence of lung wis : t damage from exposure to industrial dusts other than silicia and pos- . sibly asbestos and such information bas come from a number of a sources The thought therefore is not entirely new to us Nevertheless it does come as a surprise to be confronted with the definite statement by two such known and reputable investigators as the authors of this paper that for life insurance purposes silica dust alone and perhaps asbestos can sufficiently affect the mortality of workers TP BHT soar eagigem APR 5 189 7 MESES, ee get mae wee ef eee? he,* See Sinoe . gg - Nee Me ed LT age oR ae derinbet eye. ore sted ds a op Se F Cy ee oN wees Pr ST, a, . neti! eae Erp Tee en Seis Sb Vgre 190 UNDERWRITING ASPECTS - DUST HAZARD - DISCUSSION exposed thereto as to require premiums in excess of standard for life insurance With respect to the hazard of silica dust exposure this conclusion involves no change from our previous thought Industries and tions with such exposure have exhibited occupa- caused very high mortality ratios largely by extremely high death rates from pulmonary tuber- culosis The authors have assembled such mortality data in their and I shall attempt no repetition of them paper As for other dusts again excepting asbestos the suggestion is made that our reasoning may have been wrong Organic dusts we are told do not cause any specific pulmonary disease and there is no clinical or experimental evidence to the contrary Metallic dust too is not harmful to the lungs and such damage as has been observed among metal grinders and buffers is caused by the silica dust from the abrasive wheels rather than from the metal dust itself And so with coal dust per se and the dust of siliceous minerals and abrasives in general and also silicate dusts always with the possible exception of asbestos But what of the greatly excessive mortality ratios from tuberculosis of the lungs in many of the industries and occupations with exposure to such dusts ratios ranging as high as 200 per cent to 300 per cent of the expected or normal mortality In the table compiled by the authors from the Joint Occupation Study of 1928 and the Occupational Study of 1937 there are listed bituminous coal miners with a ratio of 161 per cent of the expected upholsterers with 225 per cent cotton mill operatives with 243 per cent and woolen mill operatives with 200 per cent The authors have apparently anticipated this question by pointing out that many factors other than dust be responsible for a high tuberculosis mortality factors such as grmaadye of worker or selection of certain classes of work by less robust individuals or race and the tendency of some races or nationalities to drift into certain industries The further question night be asked Can such high mortality rates from tuberculosis two and three times the average be entirely accounted for by these considerations thus eliminating dust as a causative factor The authors point out that available data for unskilled workers do reveal a tuberculosis death rate of this magnitude even without the presence of dust exposure From my own perusal of the joint insurance company studies previously mentioned I have selected as another example the experience on male waiters in the Occupational Study of 1937. among whom deaths from tuberculosis of the lungs were three times the normal Here perhaps is an instance of a group wherein factors of initial erate ee : er AI Lie ae pao fn Pte Tinta ce oh seen 9 2 Yee: . MORRIS PITLER 191 fe selection race and low economic status with all that the named implies in standards of living play their parts in the causation of very high mortality from pulmonary pulmonary tuberculosis a I must admit that Dr. Lanza and Mr. Vane very logical argument in have presented a cause of the explaining away siliceous dusts as the high incidence of tuberculosis in in certain thus bringing the insurance dusty trades and experimental findings mortality data into line with clinical and If we accept their conclusion that real hazards and that other only silica and asbestos offer poses of life insurance industrial dusts may be ignored for pur- rating what are some of the further practical implications for us the This question is perhaps beyond the original paper but it may be well to touch scope of upon it briefly We cannot of course get away from the fact that mortality in the exposed occupations under the excess there whether caused by dust or by other discussion unfavorable is still such excess mortality must be covered by our premiums factors and mn exposed Most of you are undoubtedly familiar with Classification of a certain Standard Office Life UnderwOrcictueprastiAosnssociaantdionIndsuesvterriaels published by the Home recommended by its Occupation years ago drawn up and Committee This classification which has been for life insurance use widely adopted by life insurance companies with more or less modification lists a number of dustries some with silica dusty in- to organic dust exposure and others with exposure or to siliceous mineral dusts And within these industries there frequently appears a separation of dust pations with the implication that such exposed occu- occupations should be more severely treated than other occupations of similar skill within the same industry but not so grade and exposed to dust If the presence of organic dust and siliceous mineral dust is to be as a causative agent in higher disregarded mortality then such distinction between workers is no longer justified in many industries unless than dust exposure exist reasons other It is quite likely that because agrecable personal reaction of the dis- the unskilled to work in a very dusty atmosphere or nature of some such work and its low employment is acceptable only to a lower remuneration such grade of fed that therefore such individual and aoer , not because of a group of workers will yield a higher mortality dust exposure but for other reasons This situation may justify the separation of the ar higher insurance rating therefor But dust is occupations and a for no longer the basic reason separation except when the dust is silica or asbestos ee UNDERWRITING ASPECTS - DUST HAZARD DISCUSSION I was particularly interested by the statement that exposure to greatly excessive concentrations of silica dust is now rare and that even moderate exposure does not occur frequently at the present time because during the last few years silica industries have recognized the bazard and are endeavoring to minimize or eliminate it by controlling the amount of silica dust in the working atmosphere And in time ee we can hope that our mortality experience will reflect the efficacy of these measures for controlling the hazard Our business is fundamentally conservative and rightly so But as soon as experience shows that underwriting practices are too severe or premiums too high I think it can justly be said that changes are readily made However when we are faced not with an accom- e plished fact but with a prediction as to future improvement because of certain technical changes relating to one of our problems it is only natural for us to say Let us wait a while and see how these predictions work out In many instances such delay may involve just a short lapse of time The aviation hazard and its treatment by life insurance companies is a very good recent example Last year E a favorable accident experience followed closely upon new develop- C ments and regulations for the air transport industry and already re- vised practices of many companies reflect this betterment with many other companies considering such revision at the present moment mH! But in the treatment of the silica dust problem we can look forward to no such speedy results Ten and twenty years and upwards may be necessary for mortality statistics to give evidence of h the expected improvement It seems only fair that we make some con- cession to the factor of time in such a situation and try to anticipate oe the future improvement Such a course points to a possible reduction h are at the present time in extra premium charges for silica dust industries om bet unless our present charges have been and still are inadequate For wha example it is my opinion that under present scales of rates the IF metal mining industries have in general been treated too favorably E and liberalization here may not be warranted t dine A further consideration is based on my understanding that the H parceve prognosis for individuals with any considerable amount of previous Fond silica dust exposure is not favorable even though future exposure is much reduced or entirely avoided This means that improved work- ing conditions in the future may not be of much benefit to a large proportion of workers already the silica dust industries and that only newcomers and those who have entered within the last few years will get the real benefit of the improved working atmosphere Some practical method of assessing extra premiums might be devised for MORRIS PITLER 193 recognizing this difference such as perhaps higher premiums for the older ages age being a very definite measure and reflecting to some extent the duration of employment in the industry The duration of exposure itself would undoubtedly be the best measure but it presents certain practical difficulties in the problem of understatement to secure a more favorable rate and in the determination of previous exposure in other dusty trades Since the hazard of breathing a specific siliceous dust is dependent on the extent or duration of exposure it follows that the worker ex- posed for less than his full working time should be a better risk and accordingly should be assessed with a lower extra premium than is assessed for time exposure In one group of industries in particular the stone working industries we have found many instances of such time exposure There are many small units dressing mills as well as retail monument yards where the proprietors and salesmen do some carving or cutting or lettering as the need arises If the facts as to extent of exposure can be determined it seems to me that a pro rata charge would be sufficiently conservative since the hazard probably decreases in greater proportion than the dosage Before closing my remarks I should like to emphasize a point hurriedly passed over by the authors because it is outside the scope of the scheduled discussion Although there may be little evidence that siliceous dusts produce any pulmonary disease some of these dusts do have toxic effects and must not be ignored for purposes of life insurance underwriting Let me take this opportunity to congratulate Dr. Lanza his worker Mr. Vane on a very distinctive contribution to literature of life insurance underwriting and the Chairman Bender Discussion was to have been continued by Daniel Harrington Chief of the Health and Safety Branch of the Bureau of Mines However Dr. Dickson received a wire from the gentleman stating it was impossible for him to leave Washington His remarks will however appear in the printed Proceedings of this meeting i a be rf Ag eis es VR en Fare ga re 2 ee eae Discussion Underwriting Aspects of the Industrial Dust Hazard DANIEL HARRINGTON Chief Health and Safety Branch Bureau of Mines Washington D. IN discussing this paper which is both concise and informative the viewpoint will be that of one engaged in health and safety work confined almost wholly to one industry mining and it is noted that the paper by Dr. Lanza and Mr. Vane stresses mining as being of especial importance in connection with the industrial dust hazard The Lanza paper is concerned largely with the health aspects of the problem and this discussion will take a somewhat more inclusive viewpoint with safety rather than health predominating though on the other hand the discussion will in large part be limited to mining rather than industrial work in general In connection with the problems likely to confront the employer in future compensation obligations with regard to dust it should be remembered that breathing dust is by no means the only hazard offered by dust in industrial work that may require compensation payment even here the harm to the health caused by breathing dust is not necessarily confined to the lungs as dust of some kinds is known to have a detrimental effect on the nose throat and bronchial passages as well as indirectly the heart stomach and possibly other internal organs Externally dust may cause injury injury to the eyes ears and skin and some dusts on contact with the perspiration are absorbed with definite harm to the health of the victim Moreover heavy concentrations of dust in the air materially reduce visibility in some instances as in the storms in the Dust Bowl in the Central West dust in the air reduced visibility to virtually zero in midday with the sun shining brightly Obviously in industrial occupations dependent on artificial 194 11 S S the Fork oted eing ard ects sive on ing yer red at es ave Fell ns .nd ite of air ng ial DANTEL HARRINGTON 195 light or with but limited amounts of natural light available any de- crease in visibility caused by dust concentrations and the decrease in visibility may under some circumstances amount to 75 per cent or more is likely to decrease efficiency materially and also increase acci- dent occurrence with a resultant increase in compensation commitments Some dusts coal zinc aluminum and scores of others mineral and mineral are explosive and many are subject to spontaneous com- bustion with consequent bazards to health safety and property More- over many dusts have detrimental effects of various kinds on as distinguished from persons machinery growing property vegetation animals dwelling bouses and other types of property are damaged by dusts and compensation of some kind is often exacted from industrial con- cerns through damage suits or otherwise . With knowledge of these facts concerning the numerous in which dust is likely to be unsafe unhealthful or otherwise ways it would seem logical for an industrial harmful executive who is trying to pro- tect bis employees from harm and his organization from undue avoid- able expenditures because of various dust hazards to disregard tech- nicalities and concentrate on reduction of dust in the air at bis plant instead of splitting hairs as to the size kind quantity or any of the scores of other uncertainties as to dust No answer is yet available to some of these questions and in many instances probably never will be and Prevention of dustiness in the air where human beings must work elimination of dust or retention in confined places and under complete control emphatically should be an integral part of the ation of any industry in future if operators are to avoid oper- heavy ex- penditures for compensation and other damages where dust is left uncontrolled and sufferers can assign responsibility for its origin The progressive industrial executive who has become convinced of his obligation in trying to protect his employees as well as his company wants to know immediately what constitutes a harmful amount of dust and how to eliminate or reduce it here again the answers are not easy or as specific as might be desired From the viewpoint of harm to the respiratory system it is general- ly stated though actual knowledge is by no means certain that the particles of dust such as those of free silica that affect health adversely when they enter the lungs are those less than 10 microns in size various persons have disagreed as to what the maximum may be 10 microns or 8 or 6 and some say that the harm is really done by particles under 2 microns in size In opposition it is stated that fibers of asbestos dust as long as 200 microns have been found in the lungs of men and undoubtedly exerted at least some detrimental effect acs 3 et CE : oe See Delve (98 TCS - Spee han) Meet Fad ws hee Dat ad hte AEE eS . neat Fae fa art t, cyan etn sees + S20 pees, S Zz -e =a 3, eyete eee = eee mae ee gt at ahi ores SAMS ee nn = UNDERWRITING ASPECTS - DUST HAZARD DISCUSSION Since a micron is only about one twenty thousandth of an inch or much smaller than the naked eye can see it is usually assumed that the larger dust particles that can be seen floating in air and settle out relatively fast do not harm the health This is certainly a mistake as the larger particles that float in the air some of them 100 or more microns in size if present in considerable quantities clog the air ; passages leading to the lungs some of these passages have agencies that under ordinary conditions intercept dust particles before they can reach the lungs and this clogging allows the smaller and probably most dangerous dust to enter the lungs unimpeded A common definition of an atmosphere so dusty that prevention action should be taken is that any atmosphere in which dust can be seen by the naked eye is too dusty not only for health but also at least in many instances for safety and efficiency If the visible dust is eliminated much of the invisible and probably most dangerous dust will have been removed also and health and other hazards very likely much minimized or even removed After the visible dust has been removed it may be necessary under some conditions or with some types of dust to investi- : gate more thoroughly the occurrence of invisible dust by means of the impinger konimeter or other instruments but unless litigation is effective or threatened such intricate studies are relatively unimpor- tant if the visible dust has been eliminated from the air of working places Manifestly if dust is not produced it cannot get into the air or otherwise become harmful and some relief from dust troubles in industry can be achieved by using construction practices processes or equipment that tend to obviate dust In designing and equipping the places in which employees must work the progressive industrialist would be wise to try to prevent the ct: formation of dust or to control it if it must be made and should Peleg choose machinery methods processes construction etc. with dustprevention or elimination features instead of those that produce or ie. disseminate dust even though such features may increase the cost of the machine or process The emphasis now being placed on dust in its various phases and the high costs contingent upon it make it almost imperative that hereafter more thought be given beforehand to dust prevention than has been given in the past For example excessively i dusty processes or practices should be discarded for others that pro- aes duce less dust or they should be isolated somehow as by housing .Sit them tightly in a separate part of the plant or using them when a minimum number of persons is exposed to them or when there is a maximum of time to remove dust as well as other harmful properties SS toe Ne NT. SE M3,Z.a rie DANIEL HARRINGTON 197 orefficcientonstituents Such installations or practices should be kept in full operation efficient operation constantly however if if they are to perform the service desired Moreover a reasonable amount of common sense should be applied in handling a control practice or system certainly it is the height of folly to use an elaborate exhaust system to take the dust out of part of an establishment and then exhaust the laden air at such a point as to allow it to be taken again into the same or some other part of the establishment or of an adjacent one through doors windows fans or by other means If dust must be formed as is true of many industries several effective methods are available for preventing its dissemination into the air or into places where it may cause trouble These include wet methods such as wet instead of dry drilling wet instead of dry crush- ing wet instead of dry handling and wetting or washing down floors walls and rock faces In general water is among the most effective available aids to prevent air dustiness even though in some instances wet drilling does give off some dust and wet grinding is by no means dustless Notwithstanding a growing tendency in some quarters to decry the effectiveness of water or wet methods at present their use is probably our best defense against dust dissemination in mining and tunneling etc. and erly The use of exhaust devices such as hoods traps for drilling has a definite place in dust control particularly in surface plants operations Under same conditions exhaust systems when propinstalled and kept in repair and operation not only perform the removing function but also more than pay their way in actual value of the recovered dust An installation in a surface plant processing one of the metals cost approximately 7,000 to install and the dust recovered daily averaged about 25 in value moreover the air of the plant and the surrounding walls and other surfaces were kept virtually free of dust On the other hand although dust traps may be used with dry drilling in certain types of surface or surface excavation work they have not practice underground been found There are applicable to general drilling several reasons for this some of which may be removed eventually Some types of rock cannot be drilled dry with any degree of effectiveness and as yet the available types of drilling traps or trapping systems are not workable with Subsequent wet drilling If dry drilling can be done sonie of the traps now avail- able will ordinarily do a good job of removing the dust from drilling but this will leave the rock and other surfaces top timbers ledges sides and floor in many cases dry blasting mucking many oa on ie ) a P | . i GRANCE GRANCE cr ::-= finan Card By Fagen ee aa a seen eS wor er Se aeteeer = inter See eee oS fers, ae eS Taio eae Tee ee S a ee ae Se Be us ee 198 UNDERWRITING ASPECTS - DUST HAZARD - DISCUSSION timbering bauling etc. will then help to throw into the air the dust dr certain to be created in large quantities by blasting and in smaller quantities by the other processes the dust thus thrown into the air tic will settle on dry surfaces to be thrown into suspension by any and all activities Dust traps also are cumbersome especially when used re in the confined places typical of mining and tunneling As previously the es indicated however dust traps with dry drilling may have a definite of place in surface or surface operations where dry drilling can be wee ho er done and under some circumstances may have advantages over wet dry drilling especially in very cold weather Some experiments are now na under way with use of dust traps in wet drilling and these may i ultimately have a place in some prevention campaigns 750 Ventilation is probably the most effective control practice the available for many industries although it ranks second to wet methods ste in others Where conditions permit effective ventilation borne clo dust can be removed or its concentration kept diluted to give almost thr complete immunity from harm of a respiratory or contact nature occa- sioned by dust and to minimize dust hazards of almost all kinds in- cluding those connected with spontaneous combustion though it may enhance hazards of dust explosibility in some instances The ventila- tion in some cases should be induced by exhaust methods but in others forced or blowing systems are more effective especially in connection with underground work in places where temperature of the air is high owing to rock dripping water or some such other condition as rapid oxidation of surrounding rock timber etc. To obtain really effective ventilation in such work as tunneling and metal mining is usually very difficult because ordinarily only one opening is driven instead of having workings in pairs as in coal min- eer ing where fresh air flows in one opening and return or contaminated air in the other Conditions caused by the dust problem may force LE parallel openings to be used in connection with many tunneling and mining operations of the future and notwithstanding the violent Ca obiection this suggestion will raise it is logical to believe that in many vee instances there would be definite savings in dollars and cents as well as in safety by the opening system with its numerous advantages wy as to ventilation health and drainage compared with the many disadvantages and hazards of the present opening system In fact about the only real advantage of the latter is the fact that its use is customary Dry drilling is without doubt the dustiest occupation in mining tunneling and quarrying and it continues to be used far too much in mine quarry and tunnel work in the United States certainly if dry O S T a iee OOe aeepeya ae A e ee ee oee,e DANIEL HARRINGTON 199 drilling is allowed at all it should be done only with auger twist drills or with simultaneous use of effective dust traps Wet drilling as practiced in the United States with water forced or drawn through the drill steel by compressed air is now under fire because it produces relatively large quantities of dust even though the material floating in the air usually is wet Much of this criticism is imaginary but some of it is legitimate and the trouble is due largely to the fact that the boles are collared or started dry and in some instances at least drilled dry for several inches The dust caused by this dry starting impregnates the usually stagnant air of the ordinary underground tunnel or metal working place and leaves it so for much if not most of the working shift after the dry starting has been completed Sometimes the driller unduly limits the amount of water sent through the drill steel and while he nominally is drilling wet the actual practice is closely analogous to dry drilling because the compressed air that flows through the drill steel forces excessive quantities of entrained dust bubbles or particles out of the drill hole and into the air of the working place Sometimes too the drill is out of repair and allows far too much compressed air to flow through the drill steel When e reasonable procedure is follow i and wet drills of present types are used the amount of dust f In drilling can be controlled in fact this is actually being done by numerous alert conscientious mining and tunneling companies Some companies in the United States and Canada are now experimenting with rock drills that do not allow compressed air to go through the drill steel but require the water to be forced through the steel by its own pressure these drills are said to cause less dust than the usual types in which water is sent the steel by compressed air but the practicability of the newetrhrotuygphe of drill is debatable and its use is still rather uncommon in the United States or Canada Without doubt present wet drills can be used so as to keep dustiness of air well within safe limits if employed with care and judgment in collaring wet using plenty of clean free water keep- ing the drills in good repair with adequate regulation of the proportion of water and compressed air flowing through the drill steel preventing the exhaust from the drill from impinging on nearby dusty surfaces of muck piles floors walls or timbers and throwing dust into the air and planning ins far as feasible to reduce drilling of upper holes to minimum Upper Upper holes whether drilled dry or wet are relatively beavy producers of dust in the air of working places Next to dry drilling blasting rock in mining quarrying and tunneling causes the most finely divided dust to be thrown into the Taree ead 5 Eeny eYaa a5yone ~. Y PR! PTI ORBITHGR ' [2 a Be &- _ 3 re . ~ -~" i . i. y ayia ted [3 i acorn arg Teer reery 3 48 ; 2 od , 200 UNDERWRITING ASPECTS - DUST HAZARD - DISCUSSION air of working places Also blasting with the heavy charges of explosive required in many mining and tunneling operations impregnates the surrounding air as well as the muck piles with considerable quantities of poisonous gases such as carbon monoxide possibly oxides of nitrogen and in some kinds of rock hydrogen sulfide and other dan- gerous sulfurous fumes Virtually all of these occur in such quantities and percentages under some circmstances as to asphyxiate persons who may breathe them or to cause serious often permanent illness Many of those who have studied the incidence of dust disease believe that breathing even small quantities or percentages of extraneous or harmful gases such as carbon monoxide oxides of nitrogen hydrogen sulfide etc in the atmosphere inflames or otherwise adversely affects the respiratory organs especially the lungs making them much more susceptible to harm from breathing dust particles Without doubt blasting practice of the past must be modified and reformed if employers are to avoid heavy penalties in compensa- tion and other charges due to the inclusion of occupational diseases | one being dust disease as cause for compensation payments in the laws of the various states If at all feasible blasting should be done | | at the end of the working shift or on an off shift and the dust and laden air from blasting should be removed or diluted thoroughly before men return to work after blasting has been done Ventilation is of course an essential agency in cleansing the air after blasting in addition the place walls floor roof or top timbers etc. should be wetted thoroughly before blasting a water blast should be kept in operation during and after blasting and the region including the muck pile thoroughly wetted when the workers return to the face region after blasting The muck pile should also be kept wetted at all times while it is being loaded out as the water not only tends to : settle the dust but also either to absorb or otherwise aid in the dilu- tion or elimination of harmful or poisonous gases from blasting which usually cling to the blasted material In general the larger the quantity of explosive used the more finely divided is the blasted material the more heavily is the air impregnated with dust and smoke and the greater is the quantity of the poisonous gases left at the place hence methods should be used that will tend to reduce the quantity of explosives used and the gases and dust produced In this it will be found that the use of stemming or of some types of blasting plugs now available will confine the explosive more definitely and therefore increase its efficiency and reduce the quantity of explosive used It will also reduce the amount of poisonous gas evolved and possibly the violence of the blast as well as its tendency to produce dust and disseminate it into the surrounding air It would be well for users of we ~ ee pie me, t , w om 4 -4e - : -! Sr men Lb ee on, * tee * ee es ~ ral te aL Ore So. hee ae ota. TT eS emer ION f explo- egnates e quantides of er danantities ns who Many ve that harm- sulfide ts the more odified pensaseases in the done t and ughly lation sting hould pt in muck egion it all is to diluThich ntity . the the ence Cx- 1 be now in- l the dis- of DANIEL HARRINGTON 201 explosives to investigate types known to give off minimum quantities of harmful gases on detonation and to use them moreover elimination of the use of fuse and substitution of electric blasting would help to reduce the poisonous gases from the blasting process Explosives that have been held in storage too long or stored under unfavorable tions as to moisture temperature etc. are likely to give off condi large stihtoiuesldofbehatramkfeunl ignases if they detonate at all bence the utmostqucaanr-e storing explosives and in seeing that they are not held in storage too long before being used Dust respirators of various types are now available for use in excessively dusty atmospheres They are cumbersome and inhibit freedom of movement making them undesirable for constant wear throughout a working shift though they can be worn readily for several minutes at a time nevertheless they do give adequate protection to wearers against inhalation of dust into the respiratory system but essentially no protection against poisonous or asphyxiating gases Dust respirators should be regarded as useful for and then for relatively short periods and adeqeumaetregednucsyt ppruortpeocsteisononfloyr workers should be of a more fundamental nature that is the quantity of dust should be reduced at its source What might be designated good housekeeping has a definite place in prevention activities Dusty materials should be stored in dust- tight containers or bins Dusty processes including the handling of dusty material should be conducted as far as feasible in tight compartments or structures tightness of which should be maintained Ledges or surfaces on which dust may lodge and accumulate to be easily thrown into the air by some shock or movement should be as changed far as feasible to prevent opportunity for such accumula- tion if this cannot be done such surfaces should be cleaned cally by vacuum process by washing down or by sweeping periodi- the latter is a relatively poor method and should be used if possible only when a minimum number of other workers is present Floors should be kept as dust as practicable and the use of water methods is recommended where they can be used Air for otrhewaussheinogf workers certainly should not come from dusty sources One of the most important features in connection with prevention of harm to the health from dust is the physical examination unfortunately this is clouded by so much controversy that its effectiveness is largely nullified though it should be one < the principal cogs in the machinery operating to minimize harm to the health from dust in industry Without doubt every person employed in an industry Fran Go:ng e ee e ae t ee ee, es ao yd : : eh15 Uh ioet:t be ua ; t qa = was RDO 4 8 3 cms 5 A oct aso pgs Sa a es Morty POP Taney, pore ~*~ 202 UNDERWRITING ASPECTS - DUST HAZARD DISCUSSION where considerable dust may be present in the air should have a rigid physical examination by a competent doctor before employment if the examination reveals respiratory trouble especially if tuberculosis is involved the person should not be employed Moreover at in- tervals not exceeding 12 months possibly 6 months in an industry wherein much dust is present in the every air person should have a rigid physical examination if disease is shown to be the victim should be transferred to developing is available dusty employment if such Handling physical examinations in a manner fair to the worker as well as to the employer is a problem that should be worked out and it must be admitted that up to date this has not been done at all adequately Prevention of dust disease is chiefly an employer responsibility and he should not hesitate to shoulder it with a view not guarding the health of only to safe- persons under his supervision but also to re- lieving his firm from the heavy financial burden likely to be assessed by compensation or legal authorities should any considerable number of employees become afflicted with dust disease how little is known about the When one realizes cause or cure or even the alleviation of this disease it seems sensible to do anything practicable to reduce the amount of dust in the air of working places This does not the employee should not help himself it is mean that as manifestly as much to the employee's interest to avoid dust or any other disease as to avoid having accidents occupational However information on occu- pational disease including dust disease is not a form understandable to the worker the readily available in employer should therefore conduct an educational campaign to inform his foremen about pertaining to occupational diseases and have them transmit mtahteteirns- formation to the workers The latter will then be able to more wholeheartedly in trying to eradicate these dread diseacsoemspefrraotme industry or at least control them more effectively than has been done in the past In this somewhat extended discussion there has been much devia- tion from the paper by Messrs Lanza and Vane and this has been done with the idea of giving a viewpoint of a somewhat different than that embodied in the nature Lanza and Mr. Vane very excellent presentation made by Dr. Chairman Bender We have Mr. R. J. Vane of the Statistical Bureau of the Metropolitan Life with us I wonder if he will talk on this subject Fer ee ore we ae 2 Sart cmee ae, W :S COS = ere STO Pan I ay ay Por we* =~ ey Pe wee. Tae 2 rd eal * gE Deg tomes GNA TS rigid at if ulosis it in- erson have ping such o the orked done bility safe- > re- essed nber lizes n of the that uch onal ICU- : in fore ters in- ate om one cal ilk DISCUSSION 203 Mr. Vane Mr. Chairman ladies and pected to come up and say anything I gentlemen I hadn't ex- which we had thought with the long paper rather prepared and which Dr. Lanza read and also the long full discussion which Mr. Pitler dust and underwriting might be concluded gave this story about I am in quite hearty agreement with Mr. Pitler has made with many of the suggestions writing practices regard to applying these data to our underHe pushed the implication to the limit but I on the whole the conclusions are sound think lists In my own mind it is very clear that for we have just those two dusts to consider Presuenndtercwlraistsiinfgiuncderwritingatpiuornposes which divide up trades in which there is the basis of exposure to organic dust on exp We will all to such dust I think are not up to the minute ha sit down and revise our occupational rating lists throwing out ma . of the classifications based on unless we are dealing with silica and asbestos exposure to dust You may have noticed that Dr. Lanza and I limited the cussion to tuberculosis disWe could not get sufficient data for other diseases of the lungs upon which to base that any conclusions It may be pneumonia and some of the other acute show a greater frequency in some of these respiratory diseases may data we have I doubt that occupations From what affect the total they would be of sufficient magnitude to mortality and consequently the underwriting practices I don't want to to answer say anything more but I would would be very glad questions any questions with regard to the underwriting underwriting phase Any on the clinical or laboratory side you will please address to Dr. Lanza Dr. Dickson Mr. Vane will you make a comment about foundry workers I don't recall any reference to that in the paper Mr. Vane The mortality of foundry workers you mean Dr. Dickson dusty of course Well a general comment The whole foundry is whereMrw .e Vhaanvee fYouensd the whole foundry is dusty but the only place has been extremely high death rates from tuberculosis among the chippers Probably if we had a breakdown for all the casting cleaners that is the tumbling barrel sand blasters the scratchers and all the operators the are performed to variety of operations that scrape off the sand which adheres to the we would find very high death rates from casting sand is as you know silica tuberculosis because the RTT oa Ble i in RET { ET OY RIOTS TER Te Shit t TTT Uae aiSeere cdit ed E Ssteuh)PASM, | i} ee A fe Feo wpg, ST re ws ma) UNDERWRITING ASPECTSDUST HAZARD HAZARD DISCUSSION DISCUSSION However regards regards other workmen However However However regards regards other large workmen casters the furnace furnace men foundries in peculiar operations operations that are carried death on in the foundries pneumonia thing that they have tremendous tremendous tremendous death Whether is due to the exposure due rate from variations temperature temperature whether whether due the heat smoke suden do variations know don't don't any due proved proved the smoke point one way the other studies have really pneumonia pneumonia the point leading cause death doetahtehr it is striking striking striking that pneumonia situation situation we have found for among foundry workers would other other occupation as regards come back to the point and that in the cleaning cleaning group , you would expect high high mortality from casting tuberculosis cleaning group, tuberculosis Dr. Evans May ask ask the bowl people doctor's experience the the dust Mr. Vane Dr. Lanza the question been is the mortality in the dust living the dust bowl bowl area I don't think bowl statistics that living the dust dust bow] we have any statistics the effect Dr. Lanza You mean with Dr. Evans Silicosis pneumoniaansud ch tothherintghingspostshiibnlges on the lungs? Dr. Lanza I don't think that industry clinical point of view Outside sufficient you don't don't concentra- concentra- a tions of dust containing silica sufficsiuefnfticrioaedsntican use Ssoiluictohsiwsesgtet concentra- certain chats which are the tailings the mines , build the roads high wind blowing chats practically practically j 100 cent cent silica When blowing dust dust the aiyrouanadndindusotnreial mipogphultationanturally naturally think then that effect of upon the industrial these quantities quantities dusts stirred stirred comparable comparable to industrial industrial effects upon up up the wind would working el the men underground , but matter who dust you of wind see a: most most of dust chat roads is too large large storms storms and when a You sweeps across dust that causes causes silicosis get the lungs frequently frequently kites can't evidence evidence of dust silicosis and whereas whereas very hazard just dp the evidence as not you the can may an indication indication dust wptae have a hazard hazard with indication as the air So you can't tie these a indication just in in the , again the large two things together together to dust Alara, quanties quanties dust the storms 9 chat wind blowing blowing chat roads and that that what FdL piles piles but short time You you get in industrial industrial occupations occupations ocupations where don't get large quantities quantities of man is exposed week in dust hours day day in and week week out dust month in and year There There nothing com- month out and year year after year There There and out, parable parable to that cut and year after week Parable to that. year, There is nothing com- s 3 wo - we aR ance es af Aa oe SION furnace d on in $ death to beat to the proved imonia quation would group dust what bow .ngs ma itra- ouri the ent of ect DISCUSSION 205 I don't know anything about the bowl and that sort of question of dust bronchitis or other thing and what it may cause in respiratory infections or influenza or in the dust the way of pneumonia specific or accurate data on that subject Chairman Bender Are there any other questions on this paper Dr. Clark Young Just one question about the tween silicosis itself and tuberculosis distinction be- arising from silicosis Do assume that the silicosis deaths are you nature or do some of them have it witprhaocuttictaullbyercaullwoasyiss tubercular in Dr. Lanza I think perhaps that can best be way Men go to work in illustrated in this the majority of men who an occupation and what do you find Well go to work in any occupation that you find in occasional rays Then a few in have had tuberculous infections maybe an proportion will slightly active As arrested tuberculosis or of men it is you know when you make studies of thousands quite surprising to find men who have had tuberculosis who are healed and those with active culosis who have never been sick and never vkenreyw ctohnesyidehraadbleit tuber- These me 1 go to work in an to silica dur The fellow industry in which they are exposed here will .ffer in who has an old bealed childhood scar up work and no way I believe from the fellow who to whose lungs are ordinarily healthy goes The man who has a certain amount of tubercle damage to his lungs is had silica effect sooner than the other two going to get a is severe enough ultimately the fellow Now if the silica exposure to get sufficient silica who had healthy lungs is going condition which damage to those lungs to cause him a clinical may then result in an activation of infection - a tubercle A large amount of time energy and oratory has been in trying to decide whether tubercle infection in expended or endogeneous I am sure I don't know silicosis is exogeneous I don't think it is of very bcaonssiderable practical importance But what does happen when he sustained a certain amount of silica vated a tubercle infection those two tubercle stimulating the formation of damage and he has acti- react upon each other the intensifying the action of the fibrous tissue and silica intensifying the clinical picture intensifying the dyspnea and making the prognosis much worse Te A 7 eCe e. arte <7 ope cr, eee UNDERWRITING ASPECTS - DUST HAZARD DISCUSSION Such cases run to two general clinical types essentially chronic case that goes on for years and finally succumbs to his pulmonary disease which is a combination of silica and tubercle and those who when they activate their tubercular infection go right to pieces and die in a period of months You can't generalize too far but as a rule the the silica damage to the lungs the more pronounced is feature of the condition as well more severe the tubercle Chairman Bender Are there any other questions We thank you very much gentlemen for your definite contribution to our program The final paper of the morning is one on Injuries to the Brain and Spinal Cord Effects and Treatment by Dr. W. McK Craig Associate Professor of Surgery of the University of Minnesota Medical School and Surgeon of the Mayo Clinic Rochester and certified by the American Board of Psychiatry and Neurology and by the American Board of Surgery He is a member of numerous societies the author of at least 128 medical papers including numerous chapters in textbooks and systems of medicine Dr. Craig Dr. Craig Mr. Chairman and members of the American Life Convention and guests To be included in this delightful group is indeed a rare privilege but your program chairman gave me a rather difficult task and when I received Dr. Dickson's letter inviting me to appear here he assumed no responsibility for what I might say because he told me that I could select my own subject This perturbed me for some time until a report from the National Safety Council came to my desk and it occurred to me that in view of the fact that accidents both from motor cars and the accidents in the home seem to be increasing to such an extent that if it has not already affected your statistics it should in the near future ree ee Injuries Immedia Sc HE Natio sons were were injur 3,300,000 Th to the fact that lives or a reduc would be expect for 32,600 deat juries Deaths 32,000 persons 1 in the home O fatal accidents that although th in 1935 travel vehicles were or accidents in eve All of the & were injured in cord but a g~t and spinal cord bone muscle ar with associated blood and punc