Document re8O951870a7eGbg7v4oLxzre

FILE NAME: Union Carbide (UC) DATE: 1936 Oct DOC#: UC003 DOCUMENT DESCRIPTION: Transactions of the 25th National Safety Congress a s t il N a t io n a l S a f e t y Congress NATIONAL SAFETY COUNCIL, In c. ATLANTIC CITY, NEW JERSEY OCTOBER 5 to OCTOBER 9,1936 A itrtm tK OmIm, RHs-Carlton Hotels uud Atlm tie City Auditor! , v j.: T s y a s s i ! ! ^ jsa sr^ s. $ ?i Safety the f t Section w w in * ik hmhh i. n-->- -- - , ions of the Child Education, Hone Safety, Street end Highway Traffic and Vehicle Fleet Sections. All mdustrial members of the Council automatically receive Volume I. Volume II is sent to members be* lieved to be interested chiefly in the sessions covers. Other Council members, however, may obtain it upon request Many members have found it worth while to distribute copies of the Transactions to supervisors, foremen, and others in an administrative or supervisory position who may p!** practical use of them lor reference purposes. The following quantity prices are ?uoted **?* copies: 1 to 10 copies of the large volume, $130 each, 11 copies or more, $125 each; copies of rhe nailer volume, 50 cents each. THE Transactions are published as a condensed record of the proceedings at the National Congress. The papers of each session or division of the Congress have been edited carefully to eliminate extraneous matter and to abbreviate the less essential portions because of space limitations. Thus the material herein presented is not a verbatim report of all the speeches presented at the Congress, but rather an abridged version made as com pact as possible, yet without injury to the technical aspects ofan y address. The original manuscripts are on buTin the Council's Bureau of Information, where they are available for additional reference. Where illustra tions were sent by the speakers to the Council, these also are on file. . The National Safety Council at its Congresses seek s to eliminate from discussion matters which are n o t pert* pent to the aim of the Congress or which re contryy to Council policies. It cannot accept responsibility tor f the views expressed either in the papers presented o in the discussions based upon the papers. NATIONAL SAFETY COUNCIL, Inc. SO North Wacktr Drive Chicago \r HONORARY Amociathm or 1km a t a a r W. Ca m m u Asm or WttUAm Lew R. Palmer MEMBERS S n a . Electrical E n ain m OFFICERS (1936-1937) Dm. C H. Watson, P ia U a t D. D. Fennell, Vice-President iar Public Relations Dm. Hart E. Fished, Vice-President for Health J ohm B. Gibson, Vice-President far Community Safely Council* Hon. Harold'G. Hoffman, Vice-Presideutfor Public Safety A u m S. Recula, Vice-President far Engineering A. V. Rohwedee, Vice:President for Industrial Safety R. T. Solensien, Vice-President for Membership Alm bt W. W hitney, Vice-President for Education W. E. Wobth, Vice-President for Finance and Treasurer. W. H. Cameron, Secretary and Managing Director EXECUTIVE COMMITTEE (1936-1937) GEDUCE J . A dams. Paper and Pulp Section C. M. Allen, Metals Section C. B. A uel, Past President J. 1. Banasii, Past President C. W. Beegquist. Past President Harold S. B uttenheim, The American City Magasine W. H. Camesdn, National Safety Council, Inc. Rodent W. Campbell, Past President Rodext I. Catun, Aetna Casualty & Surety Company L ewis A. DeBlois. Past President C. W. DeMfesy, Food Section Mascus A. Dow, Past President D. D. F ennell, Consulting Engineer Dm. H ast E. F isher, Chicago Rapid Transit Company R. B. Foetuin, Lehigh Valley Safety Council C. W. Gibes, Mining Section J ohn B. Gibson, Western Electric Company Hardy Guilds , The Pullman Company Hon. Habold G. Hoffman, Governor of New Jersey E. C Houck, Ja , Marine Section H u n J. K c u r , Wood Ptodncto Section W a r n G. Km, P u t P iu idtnt Wm. C Xm u , MSwaaku Safety Cnwmiwinn Jokk E. Low, P u t P naidut . Taos. H. MacDonaid. United States Department of Agricaltu* E. J. M o a n , Portland C ru n t Assodatioo W. J.M b ju u , Chippewa Conaty Safety Carnal L W. Millabd, Iadaterial Gloves Corporation Haul* L. Minvb, E. I. da Foot de N em an ft Company E. J. 0*Baaui, Ja* Louisville Safety Cooncil Lew & Piuoa, Put President C E. Permoax, Past President Albs S. Snout, Industrial Relations Counselors, Inc. Lt. Col. Hknby A. Renincu, Past President A. V. Rohwedo, Duluth, Missabe ft Northern Railway Company D. L. Rons, ASSE-Engineering Section E. Sanpobd, General Electric Company Cb a b l u B. Scott, Past President Cabl L. S mith, Cleveland Safety Council C W. S mith. Standard Oil Company (Indian) Waltbb Deht S mith, Delaware Safety Council R. T. Solensten, Elliott Service Company C P. T olman, Past President Geonot G. T baveb, Chicago Safety Council Robot R. Wallace, Worcester Safety Council . Da. C H. Watson, American Telephone ft Telegraph Company A. W. W hitney, National Bureau of Cuualty ft Surety Underwriters W. E. Wo kh , International Harvester Company A aua H. Y oung, Past President DIRECTORS (1936-1937) Geoege J. Adams, Paper ft Pulp Section C. If. Allen, Metals Section Nelson R. A ndekson, Seattle Traffic & Safety Council F bedebioc A bcbee, Child Education Section A. L. Aemstbong, Chemical Section J. I. B anash, Consulting Engineer . J ohn J . B aeada, Publip Utilities Section Emnest W. B eck, United States Rubber Products, Inc. C W. BtaGQUiST, Western Electric Co. David S. Beyeb, Liberty Mutual Insurance Co. C u rran M. Bishop, Brooklyn Safety Council  . F . B u m s , Jo n a s I C F. S . IX I m s Y k C o S r A. W. F .E B mwm, 1W. Ho-- S. Bu h m -- M, The Pm m D. Calutm, B Stiam i W. H. Komar L C o n n , M. A. Cbutx, a II-- i t Como. Safety F U n Embby Cox, Berkeley T rafc Safety----- ----- -- W. Cbowthsb, Springfitid. l f i.ssrhw.ffl Sofa* Cooocfl J. E. Coujnby, Bethlehem Steal Co. . Loom A. DbBlom, Coasultiaf Engineer Jay E. Dbceb, M am City Safety Cooodl C W. D n m sr, Food Section Jambs B. Douglas, F U mU iMi Cae W orts Co. Da. Loms L D tnun, MetropoUtan Life lasmance Co. D. D. Fbnnbu, Consulting Eagiooor Dohalo A. FiMSKiMn. Tofedo Safety Council Dm. Hast E. F isn n . Chicago Sapid Transit Co. Hovabo B. Fovba, Burroughs Welkome k Co. (U. S. A.) Inc. William Fobsyth, Sapcrior, Wisconsin Safety Council B. B. Fchtuin, Lehigh Valley Safety Council AixxAvan Foem . Ja, Quarry Section C W. Gnos, Mining Section . Job B. Gibson, Western Electric Co. . Habby Guilmbt. The Pullman Co. Isaiah Hale. The Atchison, Topeka k Santa Fe Railway Co. IIajob Bolux'g H. Handy, Richmond Safety Council D. T. Habukgton, U. S. Bureau of Mines R. G. C Havbm. Vehicle Fleet Section T. Hkllmuth, Chicago, North Shore k ...M...i.l.w...a.ukeeR. R. Co. Chas E. Hill. New York Central Lines Ho. Haoolo G. Hottman, Governor of New Jersey E. C Holobn. Jb, Marine Section Fbbbbbick B. Hunt, Cement Section P. G. Huntxb, Power Press Section r Hi-- E. Hubuy, Eastbay Safety Council i Majou Noam ax A. Ism s. Columbus Safety Council Exwin A. Kaysbb, S t Louis Safety Council W- T homas P. Kbabns. Industrial Commission of Ohm 6 M Wab C Km m .Stmt k B & W TrafficSection c u u i M w fiw * * * * ; ^ A. E L M * M s* C o u n t y S a f e t y C o w e f l J.*. Lm Th* D * m w * Hudson iaMd Gpry^io W . K . L a n i S a fe ty D h r. B M # h > C h a n w sr 1 L u siw e rn s Z iu S S S i^ * * * ** T a n . H. MadMnauk Unifed Sfefeo * < A e rin w e Utuum HcQuain. W k Auditl m > T. H. McXnmnr. Retired __ ' F. W. M a n , Minnrents Sefety Co-cB Jam B. M ay*.EHniart.SefctyConncfl E. I.limn. FoctlaadCo m * AanMni W. j. Chiffm County Safety Council t ut U m am lutuUnilGloves Cotyocatfen E. 1L I f n tn . Employees PMkUc* ^ ? c? * , Jambs K. M aun, Gcaod Bayids Safety Cowed Habou L. Kona, E. L duPont de Nemours ft Co. R. B. Uoaunr, Industrial Accident Prevent* A ssociate E w u t MuaraY, Albany Safety Council E. J. O'Bain, Ja Louisville Safety Cowed ------ c A. Orr, The Detroit Edisw Co. fiy O m xK m oa. Kansas City Safety Council . . l n r p p . , The Equitable Life Assurance Society oi the WnJOM*Palmo, Meat Packing, Tanning A Leather Industries Sec tion .. . A. E. P aana, Transit Section David A Pattok, Newark Safety Council ^ Mbs. G. M. P*uom, Evanston Safety Council _ Cbaslbs W. Pemdock, Safety Division, Milwaukee Assn, of Com- . E. P eitoone, American Mutual k * w ,ty I" urtnclS ' Gsnaca B. Puxsauav. United States Engineer Office jcrava Porrt r roH, Hudson County Safety Council uw ar S. Rigola, Industrial Relations Counselors. Inc. ,T. C ot Hcxky A R ekimcee, Lehigh Portland Cement Co. L V. RoHWisn, Duluth, Missabe k Northern Railway Co. ). L. Ron*, ASSE-Engineering Section E. Samroan, General Electric Co. Iekky C. ScHAmaa, Erie Safety Council Cam. G. ScHOUTLsa, Rahway Safety Council  m T t. V- I# ! **? ' ' . . ' -H i I *: i ,: : ` ' v ' A N D D B B C TO aS, W H u n A. Sc<n.t^ Sum Sw l C m CNt L| . A. ssumwmiitt, R"eJt"hl"ebcTMm Sudc uCto.. Council g -- L. Simons, Naw Haven y a y v w Cam. L. Smith. Ck*dmjlSd[y Cowc f- ur g,,M . gfd--iA0 Co. (ImL) r ^ ^ B h k s to o e Valley Safety Council EW*awuni ^D^mJ i -SnmdithA. PM s! fr>ne: Ss*aflwetyy CouocU W. A. Snow, c ^ f ? ? i S c o * L 2 S S S T c - * * , o-- ------ ' A m u II. Too, CoosuWng Marine Engineer H . M. Toonu. Refrigeration Section f f T iavu. Chicago Safety Council iW. wD. T u u rn u . San Anton^io SafrtytCoaunaJi 01 c " " " " H. W ^ ? A ^ S T TeleI>h0Oe * Telegraph Co. 2 T vw n i i i i ^ `^ i^ S. e ! W hitino, l K rff `ylvT * s*fet^0Council & Surety Underwrit- i y - Manufacturer. Sec- tioo T. A. W ilson, Textile Section W H WinANS. Union Carbide 1 n 0 * ^ * 5, E. W Wikth, Rochester Safety Council H awy Wise, sbrC-. ht.antatanwoog^aj_Safety Council 1 U W otn. Youngstown Sheet & luoe v, w W Wood, Steam Railroad Section W. E .W oth, International H arv esterC a^, E. J- Zavft. Safety S^ UK Chamber of Commerce E ajo. W. ZmuttMAN, Safety Oiv. ayrac G U Zwicx, St. Joseph Safety Council The fundament' <1000! Safety Cmi jns life. If ** * continuous camp tion that h s tA j to aB types of bag rectly or indirect citizenry. It non-sectarian, and filiations. Since I it h won respect institution. Inseparable fro* the Council's wo conditions and pr cases in America! Today there at tenting every st many of the Car are 400 foreign t ship includes firms, individuals* chambers of coi organizations, t dustrial concerns companies, the ' the railroads in automotive indu sanding importa trial field. Origi ; The history c ing story, is tot In brief, the 1 Congress was I Association of Engineers in b a result, the Mi organized in year with four! first year the 971. 8 116 Tuvniy-fifth National Safety Congress fore long you have to think of some thing else to maintain the interest o f the men. Mr. Bonsib: Remember that every thing that w e do is a result o f tw o great principles, pride and fear. Fear gets re sults. in the w ay of discipline, but pride is the greatest instinct man has. Lie awake at night thinking of how you can do your work better, and you w ill think o f things that will appeal to the cm- ployccs' pride. Pay attention to statis tics. but use them correctly. Get statis tics along lines that will show you where the trouble is. and w hat causes it. W ith such statistics you can stimulate the competitive instinct, because deep down in his heart every man honestly be lieves he is just as good as somebody e lse, am i he w ants to show it. Chairm an Uoulct: The meeting is ad journed. A D JO U RN M EN T Occupational Diseases FRID A Y M ORNING SESSION O ctober 9, 1936 The session wax called lo order b y the chairman. Dr. H art E . Fisher. V ice-Presi dent for Health, N ational S afety Council, and Chief Surgeon, Chicago Rapid Transit Co., Chicago, who presided, introducing the speakers. The Lesser Known F acts About Common Occupational Diseases By DR. RO BERT B. HUNT Medical A dvisor, A m erican Mutual Liability Insurance Co., Boston P robably the leader in the parade of industrial tli>ea>cs is an acute or chronic inflammation oi the skin w hich we call dermatitis. Th is disease m ay present it self in an y type of shop, facto ry or foun dry. A n y paste, pow der, g a s o r liquid which rom es in contact w ith the em ployee's skin, even the w ater supplied by the town in which lie lives o r w ork s, m ay be the potential cause of such a skin disturbance. The wide diversity of causes together with the varying susceptibility of differ ent individuals makes the problem of control difficult. Much investigation is under w ay to determine why one person m ay be sus ceptible lo a certain substance while an other is not. It has been proved many tim es, that a poisonous substance formed within the liodv lias been able to prolong the action started hy some external influ ence. A printer developed a marked derm atitis from ink which p ersisted for two years. Finally food tests were made and showed that he w as susceptible to lettuce, which, when rem oved from his diet cleared the skin, l i e return ed to his usual occupation without a return of sym ptom s. T h e poisoning o f a llerg ic substances is usually an accumulative process. It takes time to produce a m anifestation o f dis ease, but let any other substance cause the disease, and the irritating food may be of uflkicnt strength to m agnify its action. A ll cases of dermatitis cannot be cured by eliminating offending foods, but fur ther investigation along these lines may give us a clue with which to Icsscu the loss of time from work and the di>comfort now produced liy industrial derm a titis. /.cud M etals T h e distribution of lead poisoning is quite extensive. T h e skin of the body is a protective covering, and as long as it rem ains in tact it does a good jnl> except in the case of tetraethyl lead, which is used in blend ing gasoline and which is readily absorbed through the skin, having a tendency to create changes iu the nervous system . The effect of other forms oi lead, through that avenue of entrance, is practically nil. which explains the extrem ely low poisoning rate iu typesetters. painters ami others w ho continually com e in contact with metallic lead. Lead in any form, introduced through the mouth, acts rather slow ly when com pared with the inhalation of lead dust nr fumes. However, no m atter what the portal of entry may he. lead is acted upon by the body Auids and so converted that it m ay eventually he de|>ositcd w ith in the hones. Those bony safe deposit vaults may retain their lead contents for days or for years, and if the exposure is removed, may also free the employee of ail signs 117 118 Tu'tnty-fifth National Safety Congress and sym ptom s o( lead poisoning. B u i imagine the surprise of that supposedly cured person when years lalcr, perhaps follow ing some type of infectious disease or the excessive use of alcoholic bever ag es. he aw akes to find that he suffers the aches and pains and paralyses o f an acute lead poisoning. A s the hotly fluids alter lead that it m ay be deposited, so m ay those fluids attempt to de-lead the body, and too rapid absorption may pro* duce the original disease with all its dis com forts. O ne can readily see. then, that in som e cases investigation ot previous occupa tions is unite necessary to determine the origin al contact with lead. H eating ot molten lead causes a black scum f lead suboxide to form ou its sur face. and the heat from the metal dis burses the fine powder into the air. H ence, in the p rm c -- ot sm elting ores such as /iiu*. copper ami silver, mixed with lead.- w e find a rather high lead |N>isoning rate. T h o - e ' engaged in the m anufacture of lead wire aud cahtos. batteries, glass. iNitiery and rubber industries, plumbers and users of dry colors offer their share of lead poisoning. Probably the greatest -ourcc of lead poisoning m ay lie found am ong those win* sandpaper, scrape, chip nr hunt lead paint, for the dust and fumes caused by those activities are rather rapid in their action. Such workers may become in capacitated in a iew days because the inhalation ri lead du-t causes the m a x i mum amount of absorption into the II<mm| stream in the minimum -pace of time. V h i'tiu iu m Chromium is a metal widely used as a foundation for eolors. and dusts from its various salts may produce lesions of the skiu and mucous membranes o f the nose. Chromium plating hv electrolysis may cause fumes which are sim ilarly irritat ing. Although chromium poisoning docs not usually cause death, the number of days o f absence front work on account o f incapacity which it causes is gradu ally increasing. Other dictate T h e most efficient portals of entry o f foreign substance into the body arc the ft nose aud mouth. The sm aller the dust (the size oi sntoke particles for exam ple) the greater the speed of absorption by the blood. Fum es from hot ntetals carrv not only poisons but numerous miiiuie dust particles. T h is explains the inca pacities occurring among those engaged in acetylene and electric cutting and w elding. W hen men arc so employed o v e r a prolonged (eriod of time, the constant inhalatinu of fumes aud dust m igh t prtMluce sym ptom s of the metal upon which they work. In the ship building trade, particularly in the con struction o f metal ships, w e find occa sional c a s e s of metal-fume fever. "Ilra ss chills'* and "spelter shakes" from zinc are names applied by the lay people I such diseases. T h e terrific heat a p plied to some o f our common ntetals ami alloys by acetylene torches produces suf ficient iinm-N to cau-c a tem porary inca p acity in 4 hour-. Permanent disability from such causes i> rare, however. Disease Due to Dust Twentv-fivp per cent of all workers expo-cd to high concentrations of inor ganic du-t are expected to develop changes within their lungs due to that agency. W e are at a loss to explain w hy the other seventy-five per cent arc not s o atTectcd. M ining, quarrying, foundry w o r k , grinding, sandblasting. abrasive soap m anufacturing, asbestos work, the m ak in g o f emery* and carborundum products ami m any other occupation- offer op portunities lo r em ployees to inhale mirr*>rnpic dust particles and create a foun dation for pos-iblc future incapacity. W e are interested particularly in tho-e men who -work with sandstone, quartz, flint, granite, ami sand, because they e x pose them selves to silica, and the chem ical changes between that dust and the body fluid-, in the presence of tubercu losis, m ay and usually do lead to a fatal ending. it is safe to say . in light of our present knowledge, that the action of other in organic dusts is much less virulent and incapacitating. That, however, does not allow us to low er the vigilant methods to im prove dust control and protect em ployees, because all dusty occupations arc potential trouble makers. a f * Occupational Diseases 119 Although the action' o i vario us dusts differ within the body, the exposure to asbestos fibres, present in the w eaving and grinding of dry asbestos material, offers another type of dust which m ay cause fatalities among w orkers. The organic dusts from cotton, silk, wool, tobacco, flour ami sim ilar sub stances are practically harmless. Such dusts rarely reach the lungs hut m ay cause irritation of the windpipe and large r air tubes and result at the m ost in a mild bronchitis. T lie factor which should he Imrne in uiind. particularly when dealing with silicosis and ashestosis, relates to the progression of such disease. When changes occur within the lungs a s a re sult of the presence of such dusts, nature form s car tis>uc to heal such lesions hut may fail to stop when the ih is finished. A s a rcMih. the continuation of that heal ing p m cc's may lead to such structural changes within the lungs that partial or total incapacity may follow months or ycar> after the employee has been re moved ifi>m his du>ty occupation. Benzole-Benzene Itcn/ol is a distillate of coal ta r used extensively in industry. It is an essen tial ingredient in the m anufacture o f e x plosives. It is an excellent solvent for grease, oils and cements, and because of that property it is im portant in m any phases of the rubber am) cleaning Indus trie... In the m anufacture of shoes ben zol m ay he an ingredient of the dressin g applied to the leather and of the cement which fastens the heels ami soles. Not only in the shoe trade hut in other branches of industry where employees work with gum m y, sticky m aterial, the w orkers >oon learn of the solvent anil cleansing action of this liquid am i use it freely for that purpose upon them selves. The subsequent outbreak of skin a f flictions may be the first indication of such unauthorized use. Benzol, is extrem ely poisonous, enter ing either through the nose o r mouth or absorbed through the skin. Its action ,, w ithin the body is varied and m ay p ro to" duce a multitude of signs and sym ptom s. j ^ ; J k e bone marrow becomes affected which turn alters the character o f the blood; hem orrhages are common; it m ay cause death. The fumes from benzol arc heavier than air and lie near the floor, which is an im portant point in the engineering prob lem o f ventilation. The members of the benzene group arc absorbed through the skin, and more cases of poisoning are found when men perspire than when their bodies are cool. Probably the answer to that is that the fum es may solidify as they cool ami the powder may settle on the skin. The sweat on the body may dissolve this dust so that it is more readily ahsnrlurd through the increased surface blood supply. Chlorinated H ydrocarbons T his group of petroleum derivatives has been known to science for y e ars hut durittg the past decade its advance into the industrial Acid has been w idely d is tributed and most important. Led by earlMin tetrachloride and its chem ically associated members, it has furnished in dustry with refrigerants for ice chests, excellent solvents for rubber, wax. oil and grease, thinners for lacquers and a very fine household necessity for the re moval of spots from clothes. Hospitals have been using it more ami m ore for (he removal of adhesive plaster. Due to the non-llamniahility of car bon tetrachloride, it is used in lire e x tinguishers. The rapid evaporation pro duces fum es which may smother a sm all blaze, hut w e must not forget that e x cessive heat of the actual Arc m ay bring about combustion sufficient to produce such hiproducts as hydrochloric acid and phosgene gas. bike its associated mem ber, chloroform , it m ay province sleep when inhaled by an individual, and only 1/350 o f an ounce in a quart o f air is necessary to produce such action. That thought must be remembered when a large quantity of those liquid products is spilled on the floor, perhaps accidentally. Actum should he started at once before the liquid gasifies, and employees should be notified to keep their heads up to avoid the low ceding of gas. Chemists have developed and intro duced to industry m any new products, the basis of which is the chlorinated h y drocarbons. These derivatives of petro- M2 7Veifv*/t/ffi National S a fety Coiujress to think, inability to draw a personal les son from the experience of others, over* confidence and a desire to make good on the job. These can only be overcome by careful and systematic haudling on the part of the supervisor. His is the respon sibility o f putting over to the worker the value and advantages resulting from a close observance of rigid safety inspec tion.. System atic Organized Safety Effort T h ere should be little need to make a plea for more concerted action along this line. A s aicty m m . we know bow eas ily the sm all em ployer could be put out o f buines as the result o f even a few acciden t lo c > . T h e larger em ployer, a> w ell, cannot afford to overlook the situa tion-- his losses, through w aste of time, m oney and m aterials, will seriously affect his profits and hold his company up to the public as a very inefficient organiza tion. The ever increasing cost of com pensation insurance will undoubtedly be a facto r in fo rcin g m ore consideration tor w ell organ ized safety w-ork. Personally. I emphasize the side of humanity altove the dollar and am satisfied from long ex perience that where humanity rules, the profits w ill be satisfactory. Where a real safe ty program is followed, without doul>l rlVu iency and econom y of the highest or der w ill also prevail. The Present Status of Control of Dust and Fum es in Industry By H. B. M E L L E ft M anaging Director, A ir H ygiene Foundation of A m erica. In c.; Head, A ir Pollution Investigation, M ellon Institute of Industrial Research, Pittsburgh. Pa. The problem divides itself naturally into medical, preventive engineering and legis lative pliaes. and includes consideration oi the responsibilities of employer and employee to each other aud to the public. It is axiom atic that, in case o f physical disorder, impairment of function or dis ability, the more thoroughly the cause and course of action are known, the more certainly can possible remedies he applied ur preventive measures takeu. In the diseases <>r affections under con sideration. there are tacts upon which pre ventive methods are based, and upon which further studies now in course or contem plated are. at least in part, predi cated. D uring the development of the present state of knowledge of the influence of some air contaminants on health, natu rally many theories were advanced that later scientific work has modified or dis placed. How ever, not always has the correction been as widely and thoroughly dissem inated as was the original theory; this condition, perhaps, has led to some confusion in the minds o f litany woo uave not followed too closely the evolution of knowledge in Ib ii field. _ Clarsification of Dusts Th ere are available different published classification s o f dusts. Included in such classification s are dusts, the exposure to inhalation o f w hich are. o r are likely t> be, occupational. Those that are inher ently toxic when inhaled or otherwise ab sorbed and which cause systemic poison ing. include lead, arsenic, mercury, man ganese. E x a m p le s of dusts which ha\e the ability to penetrate the deep lung tis sues and to he retained there are piartr, Hint, chert, asbestos, talc. coal, iron, clay, slate, and other types of rork dust. .Attention here w-i!l he centered upon this last group and upon pneumoconiosis, the general term used to designate lung conditions caused by dust. Silicosis, which is caused by the inhalation of free silica, has been prom inent recently in the public p ress, som etim es in a w ay that made m is understanding possible, if not probable A sid e from silica, m any of the insoluble m ineral dusts may bring about slight ch an ges in the lung tissues, which may be dem onstrated on the roentgenogram if there is silica in the dust that is inhaledA s fa r as is know n today, most of them are relatively o r entirely harmless. Metals Section 313 A bility ol Dusts to Cause Injury It has been established that the poten tiality of silicious dusts to cause lung damage is, with few exceptions, depend ent ii|M>n their content of free silica (SiO i). The development of silicosis de pend'. therefore, upon the concentration of dust containing free silica in the air breathed. in other words, the total amount of free silica breathed and re tained seems to be the prim ary factor; the length of time necessary for a suffi cient accum ulation is im portant, but less so than the total load. Silica occurs also in chem ical com bina tion in silicates. So m e o f these co m pounds have been proved to be relatively harm less to health, som e are still in the realm of doubt, and one--asbestos--m ay cau>e the industrial disease called asbestosis, which is the result o f lung damage similar to, but not identical with nor as serious as, that produced by free silica. Im portance of Particle S i n The size of dust particles in the air which an indi vidual m ay breathe is important. Not often are particles larger than 10 or 12 m icrons found in the deep lungs, except in the case of asbestos dust, w here fibers as long as 200 microns have worked their w av down lengthwise. Uncomplicated Silicosis. Silicosis, un complicated hy an infection, is more ol an impairment than a disability. It is not seriously disabling until it reaches an a d vanced stage, and does not of itself greatly shorten the life o f a silicotic. Silico-Tuberculosis. W hen a silicotic dies, the immediate cause of death is usu ally some type of intervening lung infec tion. It is uot know n ju st w h y the p res ence nf silica in the lungs increases sus ceptibility to tuberculosis, but when an adult with silicosis is exposed to tuber culosis, an active infection m ay occur, re gardless of the previous state of health. It is thought prohahle that silica dust can reactivate healed tuberculous lung lesions of the adult type; how long after such lesions have healed the reactivation is possible is not certain. Exposure of sili cotic to tuberculosis or of tuberculous individuals to silica dust is serious and should be avoided. A fter silicosis has become well cstabJish cd in the lungs, medical science has n o t found w ay to arrest the progress of the silicotic procr- toward the stage of disablement except through limiting or preventing further eximsurc to silica dust. N or lias medical science found a w ay to prevent tuberculosis from living su|>eriuiposcd upon silicosis, except through control of contact. The course of silicotuberculosis is chronic and is very diffi cult to influence by treatment, according to phthisiologists. M edical Control. A s a basis for intelli gent determination of the physical fitness o f a man for a jo b in a dusty trade, physical examination, with stereoscopic roentgenograms of the chest, is necessary. A long with this study goes, naturally, the preparation of an occupational history "With detail as to the exact nature of p reci ous work and of exposure to industrial dust-- not a valueless recording of occu pations as "laborer." "m achinist," etc. Dr. Sayers, of the U. S. Public Health Service, has developed a method of securing information for a proper occupa tional history; among others. Cum mings, of Saranac Laboratory, also has worked out a useful history blank. Standards have bent developed for the diagnosis of silicosis. There is also a suitable technic for taking roentgeno gram s of the chest in order to brin g out the characteristic lung changes. From the considerable amount of work that has been done, it is |H>ssihle to fore cast with a reasonable degree o f accu racy the silicosis potentiality of various dusts. Periodic physical examinations, includ ing roentgenograms, arc essential if em ployers are to be enabled accu rately to learn the effect of individual exposure and intelligently to transfer affected w ork men to lower dust concentrations before serious injury lias been done, or to work out a system of rotation where indicated as desirable in order that exposure m ay be intermittent. Such exam inations are helpful also in showing the efficiency of engineering control methods. T h e ability to place responsibility in case o f claim for injury is no sm all part of the value of such initial and periodic exam in ation s. Asbeitosia. Clinical experience hat shown that the inhalation of a sufficient amount of asbestos dust causes a serious type of fibrosis, which is not accompanied Industrial Dusts tr . W EDNESDAY M ORNING SESSION * O ctober 13. 1937 Tbc meeting \va- calh il I order by ( 'hair man A. S . R ckuI. K\ccuivc Secretary, In dustrial ReUuiou- ltuuiH ,lr>, lue . New- Y o rk I ity, aiwl Vice-I'rcsidcnt lo r i*'m;iiiccr111$, National Sa fe ty Council, who introtlu rn l the <|>eakcrs. What Industrial Dusts Are Harmful? Why? By SEN IO R SU RGEO N R. . SA YER S C hief, D ivision o f Ind ustrial H ygiene, U . S. P u blic H ealth Service While dusts exist everywhere in the at mosphere, it has liccn recognized tor ceu- tunes that worker- in certain dusty occupations arc less healthy than those not tt exposed. T h e number o i persons e x posed in dusty occupations comprises one of the largest industrial groups. T h e occu pational diseases o f workers in dusty at mospheres have been found to lie due to mlranee o f dust into the system by inhala tion. by ingestion, by direct absorption through the skin, by irritation o i the skin, tf by a combination o i the foregoing. The suspensions o f particulate matter in air have been broadly termed dusts, fumes, and smokes. Such a classification is neces sarily arbitrary, since- tltc line o f demarca tion between them is not very sharp, and the chief dilTcreiiiiniion i- ha-i-il on the -i/ of the particle-. Im c-iigations by the Pub lic Health Service in du-ty industries1 re vealed that about 70 per cent o f the dust particles examined were between I and .1 microns in sire, only about 20 per rent were b is than 1 micron, and the median site was 1J microns. Industrial dusts are inanilv less than 10 microns m size. However, fibrous dusts in the air, such as a-he*tos. have been found to contain particles as large as 200W mircons in the greatest diameter. While, gencrallv speaking, according to | dusts are more injurious as their L Cncmical composition differs from that of i human body, o r from the elements o f the body is normally composed,* it is dillicult to establish a comprehensive definition fo r lu.ric dusts. Sollmann,1 after analysis o f various definitions for poison, felt that it is very ditficnlt to give a definition which w ill not be ambiguous in some cases, hut tielivved that the following covers most o f the points which must be con-idrrrd in classing a substance as such: " A |mison is any substance which, act ing directly through its inherent chemic pro|K*rtics. and by its ordinary action, is capable o f destroying life, or o f seriously endangering health, when it is applied lo the body, externally, or in moderate do-(to 50 Gm .) internally." Som e dusts arc known to Ik' pm-onon-. while others, in the concentration- ii-ituih encountered, are rninparaiivi'lv liunnlc-s. H ow ever, it may he stated that bmjf/tim; dust iu high concentration i- not desuahh-. A ccording to Fairhall, the damage arising from (lie inhalation o f toxic dust mav Incither local o r remote, and depends upon whether the material is a protoplasmic poi son, whether it is caustic in reaction, or whether it is absorbed into the blood stream and earn ed lo other centers which ar<- in turn affected* It is now well established that expo-m r lo certain kinds o f dusts, such as those con taining considerable quantities o f free silica, has increased the morbidity and mortality rate from respiratory diseases; while me tallic dusts, such as lead and its compounds. 86 Tuvilly-si.rlli Xaliiniill Safrty Couiirrss Industrial Dusts 87 lia \r Iwen associatcil m ill Kcm ral svsUmic lliisls may I,- stvallouril it iili pulmonary tuberculosis. The sec...... ... . hypersensitive. with resulting o f reaction is caused by t. o.x.ic lusts |,kc- |iT ------- rhinitis, or other disturbances are saliva, water, or food, ami direct poisoning cadmium, and raddiiuumm.. AA tthhiirrdd ttyyppee ff 1 n this classification, u ' , n lrace< * absorption lv this method; other dusts may act as irritants and ady follow s tlie iinnhtaalaatluiomn oo ff ffiinneellyy dliiiv-1u4L. * . y 9xic and/or irritant. T o x ic o r irritant * metallic fume p an icles such as 71m - produce affections o f the skin, irritate m u and is known a s metal tunic fever, f t dHU are all organic dusts xvhich prmlm'c cous membranes o f nose, eyes and throat, fourth rcactum. allergic in character, e^eward symptoms, either systemic or lien causing inflammalorv diseases o f lliesc organs* * caused by breathing organic dusts M xh, [j ^ l Those producing (teal symptoms arc luaOy described as irrita n t; those produc- |*ollcn ami certain ty|x-s o f pulveri/r<| Wo. Som e inorganic dusts are aide to pcnc- anrl Hour. In a ll fo u r cases the sole fef general or systemic symptoms arc ,rate the deep lung tissues and arc o i tlie disability may | * dust inhalation, k Unacd toxic. A dust may k toxic ami Milhcieiilfy msolulde to be retained there. tlie reactions from toxic dusts result ir* Irritant . . |a m tliesc may be active in tlie human swallowing as well as from inhalation reported cases o f injury or death fol- tissue*. causing definite and erniaiteiil in jury. while others a rc inert and m ay i*r Fo r various reasons it is difficult to * f baring inhalation o f dust from organic com- up an absohilr classification tor foands, among the ch ief oilendcrs are retained for years, apparently without seri Opinion is rapidly d u n g in g regarding <. lafaaitraniline, the dinilrobcnzcnes. chloro- ous dam age; some are gradually absorbed called inert o r harmlcs du-i .md |tirtb| diaitrobenzencs, trinitropheiml, ami nitro- HMliout causing pathological changes.' investigation may prove some o f ihem mi. Mpbthalcne. Lye damage due to iiillamma- A ll inhaled particles are soluble, at lea-t m jurious. Som e dusts may liave L ,ih . tiao o f the cornea has occurred among ! a -mall extent. ! f harmless. cell activity toxic and an irritant actu m ; while 011 1 workers exposed to methyl violet ditt. T h e is stimulated so that phaguevte- remove the other hand, the 1*0-01,mg resulting Im m e dnst from paraphcnvlenc diamine lerivatives 'si It the solute is toxic, the viahilitv o f poMirc to a dust may In? the combined rfir it particularly irritating ami dangerous, 1 ,r l`ba5;c>te is affected and an im-liVritve ot more than one mode o f entrance ...loil raining not only a severe form o f derm a accumulation results. ,\t Hie -aim- time. lm.lv. However, the following la-duau- titis where the lust con u s in contact with iMrilu r -lute m ay diffuse into n n gh i'oring I dii-ls. according to physical ih.ua.tf the skin, but also producing acute iullamma- 'Citing up an irritation and -uh-c- sties and piiysiological e liir l. i> n-l i. iiun of the mucous memhram* o f the liieiu hhrosis. T h e nature as well ;- the convenience. respirators* passages.* T o x ic lusts may l>e -ohibihlv OI (he solute is an ini|Niii.iul fa* generated during the haudliiig o f |K>x\dercl **r. lit o f two i>uli'liuhT' oi apprn\ini.it-lx f- O rgan ic D usts lxrs ami in preliminary Ivt-iug operations, ci|li:il loxirilv. Il,, in,,n- . (1|,,l.|c ,, rill lint iM ll-ii " r in lr r il.nmiyc. I l.m c ir r . ml. Organic dusts are ........ . h i. I.......... , carbon.' and were originally supim-cil lurticularly the h y d rn e v tractor prnee-*. here particles are lisseminat*<l in all di -1:111.1-. til '.1.1, Imv si.tul.ililv as silica mas mie 1 roin organized -iih -ia n - derm rections." Coal tar and iiuligo txe> are ultimately prnhirc extensive injure.* ir*mi animal or plant h ie. Living dtK 1*1lances most frequently u>el. K m lc lias slalisl Dial liarm liil ,his|- 1 'ome iiud-r this classification, ami ; Cases o f amblyopia have Iwen rcportcl iuhaied into the lungs, may activate a latent Ibonghi Io Ik? o f the -ante or.ler of Irom exposure to inhalation o f tobacco tulierciilous infection; they may exaggerate imln-trial du-t*. ,th which thev an :'i. Im' I " It has been loiid that inhaled to an active tnlicrculous lesion or a eoincidcnt Iiieutly associate!. Iarteria are usually 1 bacco dust exerts a nicotine a'tiou on the infection. I f sufficient quantities o f a harm tween O.a and .1 microns, exrept in a tr organism fifteen times greater than that less dim arc inhaled, some o f it remains in vases, such as the anthrax lincillus. wIih poxlured by the same quantity o f smoked the lungs and causes a mild degree o l fibro ranges from I to 1.25 .m enu, in |.r<adi hacco with an equal nicotine content.'* sis merely through mechanical irritation, and l a to 10 microns in length ami IO ori. Severe dermatitis is experience! hv manv hut -itch fibrosis is never sufficient to inter- microns in diameter. Howeve r, it is workers handling powder containing T .X .T ., cn* unit the function o f the lung.' Jde that the la rg ir and heavier varici which is usel in making high explsives. Some writers stale that while the imhi like tlie larger ami heavier dust pallid Picric acid, which is also usel lo r this pur- nice 01 u.injioisouous dusts on health is a settle due Io gravity, ami lo not .<i,u *"* requires drving. ami in this latter stale debatable subject, abnormally high death 'ii'pt'udel in the air. has been found to pr,<luee a dermatitis. rales iroin bronchitis and pneumonia are Many llioiisamls o f organic suhstancr Picric acid is als, the oldest sxnthetir nr- sometimes attributed to chronic exim surc to nouloxic lusts. I.argc amounts .of dust are arhon-i'ontaming. are tnale ni helical' by chemical processes, u n ii ,s dve-iuf ganic dyestuff.'* fdermatitis lu-enrs among handlers o f silk with varying frequency. H-casionallx found in stip|>osedly normal explosives. etc. Sails detcrmim*d that a rash occurring hmgs. at autopsy.* toong workers in a silk fact,ry w as due 10 According to Drinker, there are four d if ferent types o f reaction produced in man by the inhalation o f dust. T h e first and most important are the pneumoconioses, such as sihroM* and ashestosis. which cause specifir lung pathology and often are follow rd by I. .\ iL \ 7 V I 7 A * f;rW i;.-| \ 7 < '/ ) / * v 7'\' ` uust from silk cocoons imported from the name implies, this,- are comprised Africa.** uouviahle particles, xvhich may or mav ik* Ik* inherently toxic or irritant, Imt wlii! niverthcless produce untoward effects in t^^ Persons engage! in the inauufaciure o f ^utrune and quinine preparations snij'er from rinn phenomena, which occur fr the most mman organism. A llerg ic" dusts, or tho* * on exposed parts o f the hmlv. and 1 winch only ecrlani persons arc or n U 'Lw Shlbe caused by ingestion or by dust, or powder form o f the preparation, e x istin g a direct irritating effect on the kin.** Dermatitis due to other vegetable dusts such as vanilla, powdered arnica, pyrethrum, etc., have been reported.** Denial lesions, o f occupational origin, have been reported among w orkers in sugar. The gingivitis caused by sugar dust is clas sified as purely meciiantcal. with latcrlevcloping cartes. Digestive disorders, respiratory conditions, and cutaneous con ditions (especially o f tlie face) were a!- found." Dock workers, transporters o f gram, w orkers in grain ami Ilnur mills. *-tc. arc exposed to ilu -ls luring their work. Du-l- from cereals may contain many impiirito--. which may cause an irritating action hi the respiratory passages, as well as inflamma tion o f the skin. Digestive disturbances, dental defects, diminution in hearing, ami conjunctivitis have liecii observed among millers, and have been attributed to the dusts to which such workers are expose!.'* b. . IIL r ;nc. Matty apparently innocuous substances may produce reactions in per sons o f iHTiiliar personal susceptibility. The term " allergy** is iimsI 0 lescnl- this con dition o f hv|>ersensitiveiiess or susceptihilitv. ami allergic phcmuneiia most frcpienilv manifest lln-m-clvcs in skin reactions. Ilo u ex'er. they may cause acute reaction' l-rwhere in the liody. When the respiratory tract is involved u*e have such well known ili-cascs as hay fevrr or a-tluuu. T hc-c diseases may level,p as a result o f hvp-rsrnsitivrncss to such suhstaners as pollens from plants, hor-chair. rabbit's fur, furs. Vaiher-. *lc. Fur in-lauce. furrier-, w orker- in rloihing i,ilu-lrif- who are exi'o-t'ii 1, xm,| .lu-t. etc., may sutler from hay lexer or asthm a." It i- mmeces-ary for the Ifoiling du-t to reach the depth- o f tin? lungs--giant pnlleofor example are re|M,rtel to proiluce llu ir ell eel a fter Iwing 'aught in the up|H*r r e s piratory passages. Should such an offending substance he finely gromwl it could reach the alveoli ami as a result probably ail phxsiologic reactions xxoubl be accelerated.'** In a -urvey o f a plant where re-10 imixed. ground, and molded, it wn- found that HO |K`f cent o f the <M-cupatioual derm a titis there was doc to hyp*rsciisitivitx to hexamethylenetetramine ami iormaldeliyle cmitaioetl in the dust to which the workers were expsel.n Duciog the first p m c e -c s ' Aw M BV h u U u t n a l 1 hi.M Twenty-sixth Xatiuual Safely Lamjress t,i lu iion spinning, collon-strippers are ex- pohd to dust arising from cotton husks and debris, which produces a typical form o f asthm a' Ordinary wood dust lias been o f interest due to its purely mechanical action, but still greater care is required in handling certain kinds, especially woods coming from abroad. becauc o f the essential oils impreg nating them, which when freed in the dust . ,, .. Iridium derntatodes), 'In c h .... W . ' Irritant dusts >,c injurious *>' liuc. * . ,, ron(, .rriu n v c or corru- when Ihe la r k is stripped oil. Tins |n. r * * " *" *-- h Z g Z ~ AS ~ . - - W K t t t t i ! - p r . : V S T m a a conimoni> " stance, the black powder maccrali'd sugarcane talks. Among b a -E fron' " " ` " l * he makers, the L y v c l.u m and spores, in * ! g f f * ?> " *5 ` " i f form o f a Id le mould (liyplmmycctc) lre ,,tm sion o f inflamin' 1 it|c he rhallan ca n . used. Ret shaken oul he * b n n e is corroded. L.m e. calcium ..xuU . he cm.es are ,p l... n n n e re d . and ca * ? * di-chromalcs are exam ples o l urn- cer are reported to have been catted by exposure to dust of arsenic compound*. C ertain aluminum salts are skin irritants and aluminum dust* may contribute to the infection o f skin and mucous membranes through mechanical action." b. Vihrosis-Producinq Dusts. 1 be m o't imiM.rtani o f these arc the inorganic, slightly soluble dusts which cause fibrous changes in the lung tissues, some o f which arc seri ous. and some of which cause little or no may affect the health o f the w orkers con cerned. Some o f the woods capable o f causing -kin lesions are B raw l wood, satin wood, trakwood, cumaru or tonka wood, black ebony wood. W est Indian mahogany. Japanese tagayasan, coccoloba. cbestnutwood, olivewcKHl. C alifornia sequoia, etc. A ll pyf- 'ns who handle these woods are not in jured. mlv lltosc particularly susceptible to th?e <ub'iances affected --the-y -c-o--n-t-a--in becoming ia u s n |M.n.l - L u r e s ........... .............. t,: - s* i Aa n.. ^" i * " " ,, .r ^ sk.i..n....w...h..e..r..e....t.h...ey alig- ht.'* t U * <?IIC 'T ^ L L t b i n c d A form I.i asthma or pa'inodiv coUr. ' ( ^ l one mode o i entrance suffered by cotton w eavers and known v #fct Ol more ina aMwruillo-is. Iia* been considered due to e Into tbt oa>* . .1 ,, m*t halation ... spores o i a mildew which so Of the Jlrectly po.sonous tunes occu r, uu the thread, * In a sod ,,Idel, prevalent arc carkm o i >ilicuMs among miners, made by ib compounds, particular]ly t , readilv l*iildic Health Service, a numlwr o i ca<e tl and the chromate. Tlu. * n i ,ivpicta ,l miliaarvy calcihfication were ke pabisorbed .boy; the nutrous n7wm r` , ( j eouniered. Ii -n..M..ai.n..e..dI sdmme..ars oi ihluo>e ra*rr fiueHd poassecs into thlwe stomach anmdi is dit>ssoUeU * tu ^ n T " rraauuscw miioiurei.th1a1n-a- .cr*y; m--o-d--e-r-a--t-e- degree o f fibrosis o f the lungg-. Moreover, there 'sceeeimms to be no evidence that any other constituent o f ordinary dusts can influence so unfavora bly a pulmonary infection.* Although other lusts, when inhalc*l m sufficient concentrations over a long penol o f time, have been shown capable of pro ducing a pulmonary fibrosis, nevertheless, the pneumoconiosis characterized by nodu 2. U n .X G O K G .IX IC M `S T S . Th ro...tain par I s l e , rapahtc o f exhihitinR the |lfllilc'lm|IHmmii uiMa .>.i lHifies1 (espe.c..i.a..l..l.y* t--h--e |-.ro|rlv o f. rcprmluction_ o_ r___m__uil.t:i.pil.iacait:i.o..na). <uch bacteria and fungi. T h ey are usually ioiind m low concentration* and arc ."* Mh-.l with nonliving dust-, m tlu: air. a. Hacuritt One o i the most important among thv*c is the anthrax lorilltt. which i ' contained in the d ii'l ironi kin*, iu r'. wool, and animal hair, horns, hoots. Imue. n c . Tin* lisea'C may occur in two fo rm s' sittaneous (in which the organisin a lin * the skin), ami lu ttu u n u tr y (when it is inhaled, as in the lorn* o i anthrax known as wool- M irier'* di'cas-).'* Cases 01 Icianii', r|Mrlcd in oinnclim with jnie nianuiacture. were traced to the raw material, the bacillus having been found in the iaclorv ditst.** Diphtheria, nihercu* losis. >mall|Mx. typhoid, or other hacillus|.rHiuc*<l` li'vases. max result from exposure to infected dust*. Bacterial sensitization can lie the cause of any o f the allergic diseases, namely, asthma. iHTcnnial. hay fever, urticaria, angioneurotic lema. zema. or migraine headaches.'* b. fion/i. Dusts containing the mycclia and spores o i parasitic fungi give rise l* annoyance and discom fort. " M altster s itch from the dust alone lias been reported. In Provence, reeds used for ceilings are stacked while still wet and undergo fermentation; they become covered wiib a white powder (a dry fungus o f the Mucor fa m ily : Sporo* examined e re positive tor llimtils. I. ,ypcs ... AsperRillt.s ini.Ki Ih:ii.r idenlitt. \.|.|. ......,.|.,..- sMulbhjeccts hut .me e re .arm..t_e_a_m. .s.t.e. .r.s, icedm...iIlIl wwio>rrkbie-rr> oor rc*'idite'initMtf 'nail agricultural towns where S ' ncirki ln l I'arm ers ;re w p ..M-d to innei ilm -'liing hvlu'at. haling hav. bandl: various small grains.*' Some oilier iiuigus <li'ases 'ii li a> aciir. m v c o 'i' and hlasioinyeoM' are ."K-iai. with <M-cu|atM*nal .x|Hisurc t* dii't. T. it.rm rr (Hciir- among w ork er' handli: by the gastric |Ui. c. AccordinR lo Fairhall. |x-rloraU-il nasal ,^epgtuuimn is a common occurrence^ ;among _W_O.ttk,c.r. .s wittithi hbi-rclhirroommaaltCc dluusstt*s.* In a uudy itu'le by the U. S. ru b lic Hea|*b S>eerrvviiccee i1t1 w a0s found that .c..o..n..t,inuous lailv. e|wsurc to conccntraiions ot chromic acul mist greater than I milligram in 10 cubic meters is likely to cans: dohnite injury to .he nasal tissue.- It is l.. live.f ll.at a imilar concentration *i the dnsi would lc equally toxic. .jraw . hav. grass, vegetable h.hri' utatr In the case o i poi'Omng irom some heavy nated with mould, etc. Actmoniveo'i : metals, exposure inay I** to loth dust anl likclv to affect people engaged in commerce vapor. For instance, investigations have handling, 'lorm g. au*l cleansing of gra:' shown the safe limit o f i/u/ exposure to (gram distilleries, flour mills, giam criK lead oxide dust and iumes to he less than iiig. h rew erif'. ami malting hoii-C'. vie.). l i mg. per 10 cubic meters o f air. except lor prolonged exposure." In cxp o 'tirc to 11. In o rg a n ic D u sts mercury dust and vapor, it w as shown that Inorganic om|Miuuds are 01 min: rigiu. not re<|iiiring living organism 1 produce them / A number oi dusts iisuallv d a s s c l as toxic may. under sort ecoonmdliiltiiomnss,. pprroixdluu ccec uu nn ttooww aarndl eeftfteecetiss ccn ff human organism. Classified under iiiorga* are lo xic auIMr. .i.r..r..i.t.a..n...t. cfdi..r.*ss-pMrAodituik* ing, and nonfihro'i'-proilucing dii'ts. ,1. To vis ttnil'str Irritant. T o xic dusts a those which arc iiilierenily toxic when i' Ihc incidence o f chronic lucreurialism in creases rapidly with increasing m ercury concentration, a fter such concentration e x ceeds 2.0 mg. per 10 cubic m eters.* Alkalis and .m..ve.t--al.li.c' oxides are co,mmon1 of dermatoses. L>c potash ami HUmoce are known to cause irritation to plax lerers, cement-makers, bricklayers, masons. Itooecutters, modellers, and metal platers. Ulceration and perforation o f the na<al sep tum occur among workers expose! to the haled, ingcslctl. or otherwise absorbs dual of soda a sh ; systemic poisoning also Among those which prmlucc systemic V* V- WHt, from inhalation o f calcium evanimide soning, some o f which arc also irritant. dost* 0, ytdsis from heavy metals and their sa l b | such as lead, mercury, arsenic. cadnnoXBiWBB ,i?f dermatitis, scleroderma ami can- lar fibrosis has to laic been shown cbm- -ally ami experimentally to be associated only with the inhalation o f dusts containing tree silica. Since Ibis lust. In exert its harm ful acliun. ntll.t enter lire liner ilitisinn, o f the bine, lire ixtrlielc ,i/e o i the utnu>|>ln tie .b i t iiiav W ar a rlelinitc re1ation,lu|> itirio n . elfeel prmlncctl. Tile Mina oiu,| l.e lrcrnl in lire air in particle, Miiaii ''` " 1 ; l t.i enter lire liner air paces anil 01 -u.b liinen.ion, lltal tbc phagocytic cell, may eiiKiili liicni. The greater m ajority par ticle fnim.l ill-on microropic examination ,.t the long tall tvilhin the limits ni rr.in I 10 J m icnai." Examples o( sibreon .hi |. arc Rranite, nuart/. anil, pninice. kit. ' In a recent link among anthracite...... .. the rnrrelalinn between cxponrc In .ln-1 (u-bielt eontaincil ilica) amt the iiiilin e e n i eonhtutional change lelt little ` >" " bt a lo the etiological siunincancc o l the ilil't in Ibe air brcatbeil. l.ikc cnirelaln.i:, ' founil lietnceit Ibe silica exposure anil the extent o f pulmonary ebange. Wbcn the inbaleil rlut consists o i silica ei.inluniil with base, silicates, some degree ol ebange in the pulmonary tissue mas result. " > " " respect asln-stos dust -eent to be lmn|ile atniing silicates in the prevalence amt -c- verity ot the disease it causes. T h e eliiei distinclinn betneen silic.-is and condition due lo simple reactions caused by other dusts is the a cm e proliferative  U) 7 v m / v *.W.i7/i A titio n u i S a f e t y C\ wi/rr.v.v huiastrial 91 reaction in the tissues which rc-u li- in progressive nodulation. Silicosis. when oner established, strongly predisposes the tunes to infection, especially with the tubercle bacillus. Chronic interstitial pneumonia, chronic bronchitis, and emphysema arc fre quent complications o f advanced degrees of silicosis. The relation o f the acute respiratory incctions to the reaction due to dusts other than free silica lias never lice established, though a heightened incidence has often lieen shown statistically in w orkers in du*tv trades. It is fairly certain that a dust dam aged lung, whatever the r;tnc. iarcs much worse if an acute infection docs supervene upon it.1 In a study conducted by the \ \ S . I' nbln I iealth Service among marble fiuishcrs in Vermont, it was found that marble lust when inhaled in the concentrations found in jhc examined plants produced a mild. hi-tleral. linear lilirosis in some eases, hut no eriotts lung changes were noted :md there was no disability due to il.c dust, even alter years o f exposure." Dust may lie entrapped at Us sUr(f . 1 ^ Mtctiou devices and thus removed and * K l v e Icctcd. fa m ilia r exam ples arc exhaust h* in grinding operations, and the devices. in rock drilling. . goggles and aprons; as well as pro- Ives, ointments, or other voiuto delay or diminish the irritant General rules for hygiene and good should also lie observed. Generally speaking, the exhaust venm tioii method, w here applicable, is to he p ferred in controlling a dust hazard. \V* may he used to entrap du>t and preventdispersal, and under certain circmn>tai* it may be o f advantage to combine thee o f water and the use o f suction. Someti a dusty process can lie completely encU in a scaled room or compartment. It lie remembered, however. that any merhr cal device o f this kind offers adequate p tcction only if it is properly drsiqcinstalled, ami maintained. A great deal o f attention has Item gi the subject o f individual protection In dus!. and there arc many types o f rr<|r lory protective devices now available. Th arc generally o f two types: 1I1.1-1- wfc provide tresli air from an imcnntamiiu' source and those which rely a liltrrr medium fo r removing dust from the Jfrrfiff1 Control. Equally important, and ffcwely interrelated with the engineering is medical control o f occupational C a r d s . In addition to directing the proper g u t r " * o f new workers, and guarding the health o f all employees, medical control is g beck on the efficacy o f the engineering aanlrol methods already instituted, o r a m w r t o f the need for new protective dcvices. j( |,u been stated that "In d u stry lias jnnT1,j |hat the best way to treat industrial Injuries and illness is to prevent them."** ml medical control, through prcem plotwent and periodic physical exam inations, is one of the most important factors in such (uevention. The preemployment examination is made .. d.e.termine the em.plo.yee's physical and mnital fitness for work. It serves to dis rinse the presence o f any contagious di- S n n fU tro sis -l'r o H u c im i Thc-e are inert, liiat is. they do not cause fibrous tissue to lie produced, but mav Urcome encapsulated or lie free in the li-sin-s; or they arc absorbed wit bout production of hhrous tissue. Included among them arc ahmdum, coal, corundum, em rrv. Iinu-imu- magnesite, marble, plaster o f 'parts <.y|.- "" i). and polisher's rouge. Dust Control l-.ugineering ami medical o .iiin .l ;Mt- ,jlt. : most important factors m ...m batm * the industrial lust ba/ard. and arc to a |.,r- , - s lent eoinplenieiitarv. / nnesriun Control. \,, | .t,t/y j,.|% -taieil in a recent paper, " I t is a basic principle in dealing with a du-t ba/ard that the dust should be attacked at n< pmiii of origin and thus prevented from In-mg disgeminated into the atmosphere." A fte r the dust has Iwen spread throughout the air it ' dilficult to deal with it. and rehanee must l*e plarcd on individual protection. Inch is never wholly satisfactory. Lanza further cites various methods used breathed. W here the use o f such a dev is indicated, only one o f the type* uppr<>hy the l*. S. ihircau o f Mines shotihl used. As a rule, it may In- said that tiu-. respirators, or other -itch protective dc -hould l*e u-cd only where cx|iosurc tut du-t is mlermitleiit ami brief, or wht -o m h * iuui-u.il condition makes a nioit-* inalc du-t control impracticable.^ W here bacteria nr other living du-t* the air arc associated with a process, -tr lization method such as increased loupe:, lure, ultraviolet ra<lialini. and cln-mi.. like cldorme or other bactericidal sub-lane may le o f use. P asiotri/alion tcni|H-raiu falmut 140* F .) will kill most orgam-i except those liearing s)K>res. Steam d k fecliou is used for horsehair, and prove* he practicable if the loniH-rature i|nc$ ' exceed 230* I*. Wool lihrcs. however. 1 their elasticity by steam disinfection, v the "I bickering" process now ued Mi Er- land includes soaking o f the wool in a fnrr aldehyde solution, and drying in a ciirre o f air at a icni|craturc o f IhO* F.u Tinare. few occupations in which there won lie a sufficient concentration o f dead h* eve. reveals any minor physical defrets which might later become serious, o r whether the examinee's condition precludes his em ployment in certain or in all types o f w ork. It should be remembered that such preemplnymcnt examinations arc not to Ik- made for the purpose o f eliminating an employee, Ihii lather for allocating him to the type o f work for which he is physically suited. A worker should be given employment unless totally unfit, or unless his disability, even though slight, would cause him to lie a haz ard to himself or his associates. Furthero>rc, the practice o f precmphiyment examinations should lie extended to include executives and officials o f industrial orgauirations. T h e purpose of periodic physical examinations is to secure and maintain physical fitness and thereby lengthen w ork pans."" Reexamination o f em ployers som e times results in the discovery o f defects am! disabilities which were not observed at the time o f employment. In such eases, an oc cupational adjustment should he made to provide continued employment, hut remove be risk o f permanent injury. n controlling dust. T hese will lie reviewed but briefly, since a paper dealing with the subject o f dust control in detail, will follow on this program. ten a to cause untoward effects in man. g-Reexam ination o f employees is required In the case o f dusts producing extcnr& 7^>^t*C.dn.certain occupations in which the irritation, auxiliary protective m c a s u r ( s n > A 9 p V e l poisonous or otherwise deleteriinclude the use o f protective c I o t b s s H A t a f t t u S L 111* ? result in the contraction Vx-v.: 'V.-j j '" v r 'H .1 1 -aTx-<\v e . _ . o f disease.** Since some occiipaiicmul dis eases tend to dear up and recur, records o f previous occupations should lie included in the physical examinations. T h e frequency o f examinations should lie determined by the medical director, unless otherwise speci fied by law. Those exposed to known occu pational disease liazards may have weekly or monthly examinations." " It should always lie kept in mind that the basic principle o f physical examinations in industry is to keep men on the job and not allow the physical examination to lie merely a weeding out process.**" References Rlovnitield. J. J. vimI P.i IIj X-tile. J. M. '*fli.l)nrniinn<M ami (umtrol f Iwlu-irial Hu-." I . S. Public Health Itullctm No. 2)7. April, 19J-, Colli*. Kdrrar U "lndu-inal PucMiikocomo--. with special reference 10 Hast Phthisi-.."' Milrm Lecture*. I9IS. H. M.S.O., l-umbot. 1 Sotlmann, Torabl. "A Manual of Pliarmi colony." \V. It. Saunders it Co.. I1iilalii|>ln.v !>*.' l-airliall. bwrenre T. "T*tie l*n-i- *nl Fumes." Journal of Indu-iriat llymene amt I om coIukv. November. r*Jf> niuAititiebt. J. J. "The S.unj.ltm; anil An.ilvi<if Imtusiriat lluvts." American Public lleatih A--ociaoon. Yearbook. lf>J5 iri. <lilts, W. K. " Dum llaranl in IniluMrv. ' Ernel Renn. I.i'l. kmlim, l9ii. Air llyiriene Foiimtaliun of Amriira, Inf, "Sil< ro-11 .nut Alliol IH*rhar>." M->Im:iI Stne*. Bull Inst, o f M ining am i MclailurKjr. l.on ilon , Ju n e I 1. 191. * " D hm. Fume*, am i Smoke*." *Veii|aooci amt Ilca llli S e n e s . Inicrnaium al l,,ilMiur 1 iflk e. t .d u i.i. 19.10 M Mfinker. Philip, "r.m -a iio ii o f Pneumoeoni- 0 - 1." Juurnat o f Im lu -ifm I lly e te n e am t l<ii eoioKv. *iciolo-r, |9iri. * , IJ>-einB." Ikcup.vtiun amt Ilcallli S*-ne*. International l^lum r *)flke. eneva. I'*. ii U -tc r , Sir Thoma. " Itu lii* in a l M atadie*." O sfo r .l l 'nivcrity Pre-*, l.um lon. I'M I. " Hurvtein. A. "N icotine A ction Irnm tithal-*l Tobacco llii-t." Journal o f liulu>(rial H ygiene. I)e- eemlM-r. 10.'?. ** VVliiie. It. Prn*cr. "Tbc 1Vnni-reo*--. or Occupational Affection- nf ilie Skin." II. K. I.vwi* it Co. 1.1-1 . I.....Ion. I'HI " Scltwarir. (.out*. "Skin l l ita r il- in A m erican tm lu u ry ." 1'. S. Public H ealth lln llv im No. I l ; . ticiolx-r, 19.11. ** lln w iiin e. J. <i. " tm lu -u ia l Ik-rniaiu-v-: T rea t m ent ami l-eeal A -|h-ci: R en ew o f Kerrnt l i t e r a ture." Journal o f Im lii-in a l llvR ienr amt Tosicolouy. July, t9 lv * "Occupational l.rsion * in W orker* to S u e a r " Belgium l.eiter. Jnurtinl o f A m erican M nlical A --o- ciaiion . Sej>t. 10. 1937. Ab-t. Journal ( tm lii-ln a l llyeien-. t-ebm arv, 19.`S, n "Flour M ill" Occupation amt llealili Seriv-. Iniernaiionat l.atiour U ffitr, fien rv a . I'UO. M ayer-. M.iv H. **Sti<erpiibili|y to iN-rmatiii* " T h e ImiiKirial H ullclin. A lbany. X. V. l et. 1917. vol. 10. no. 3. D nnker. Philip, amt Hatch. Theodore. " In d u s trial l)ut." McGraw-Hill Rook C om pany. Inc.. New York. 19lo. ... . Schw arts, fmui*. "Skin Harard* in A m erican Industry Part II." U. S. Public Health Bulletin S o . 329. Sept. I9J6. . .. ^ . ...... " Poisonous Woods." Occupation and Health Scries, International la b o u r O ftre. eneva. I9J0. / vm / v-.i.r/// A iih iiiitil .W / ,/ y ( 'nti/rrx.t B y H ours o i the fHiy My Modv Part Injured Mv Nature *u Iiimu \ My (enerai t'an*e liy m ajor suli cla^ilNatimi. under <imcral Cau*e My P rim ary Masir Causes My Secondary ('nlriliuiiug ( `iiim' ' Mv l-'orenu-u in I 'harge My Maum-r o j IV rlorniaM ir Mv ' m v 1 Ma, him-. Mat. n.il. t lc My P ari o i Vvnii v My Mi-iIiihI o i t 'oMi.M i I hr figure* ma> In- *mimi.in/(-,| m ila>> ot linu- h oi. im di. al e\p . n-e. * 'ahon award*, or othr a*<Mi.,i,,j . j . ^ C o iK lr iu iin n S r i /inn 201 preM'il it m*i I. r b f oiiktaneliif d..-. d pinion ' f M* a* ww-- salisiat ten v in ht .il .iii* i f fc this (|U(-*lloll. hilt III' l llilliT l * bad mi'-i.ik- it h r h i* niu a r y du -t 'oiiriTilration* i any are *uh|ct to *|mntaneou' <ninhu*iinn ith .-ou*e.|ui-ul hazards health, saietv and l*ro|M rty. .Many du*ls have detrimental , ( Cts ol varim is kind* on |>ro|crtv as distmKU.*hed from |ier*ms. Maelunerv. rmvinvegetation, animals, duelling houses, and oilier ly|K's o f |iro|K-rty are damaged hy u p , n t f M> Ollier rraoii to r du*t ro n lro l ^ | | iotrad, then iMir -liould i ad Iran- lOtnc o f till- rtrt-ni nit* at roni dusts, and couijHii*atin o f snie kind iften is obtained from indu*lrial concern* ihrt.ngh damage suits or otherwise. W EDNESDAY AFTERNOON SESSION O ctober 13. 1937 Methods for Protection Against Silicosis, and When They Are Justified 1 B y D A N IEL H A R RIN G TO N C h iei. H ealth and S a fe ty Branch. U. S. Bureau o f M ines. W ash in j.o n . D C While- ilu U )ti-na nil re-gar! 1 *llil`e .iihI ..ill 1 occupational d*;** ha* largely ill*>1|*-| ;im| 1Iti*. *uhi<'( t i* In-mg mor- a,-,-. iiillv ou*Mhril anil soln-rlv judged. it would In- |NHr |oht'> i*r am t-iuidovi-r to maintain H:.,i il ,, *i,,n n |K|S -mh.l and 1h.1t lu . Ill il.i\ .tod I t i-rl to roudilion* a* lln v wr sonu- yeai* ago. Tin- laci 1 that tin ld.111 0 1 iMuiuu ...................... al-d i*ea*e vilion 1* now hi 11* iiiiaucv and ran In- e\|K-'ti-| in urn rapidlv. At pr-*enl hih* all the S tair* o i ih<- * 1'i` liiiliiK Ilu- Ili- lri.1 n i C.ilmnl.,;, ami . .,| .| | HU Arkansas au.I \lis-i-. '"I" - '"i.|.. li.ah..M acts, null III. i,,|. am inn make ................. inr rn'cuiialiMiial .Ii-- ............... ' " " i ' "M in i t a li I'mn ia. Ilila u a rc . . in i. 1 lic .ii. 11, -1. , : I '..liiiiilitn. III,,,..,.' Iin lian a. h i 111 n c I... . I a - a c l ,u s ,l | . . M icliiaan \liiiii..i.t.i. M i,.,.|ir,. \,-l,iaka. \ ,* ,, I ,,.,,.' \ c u \ .,r k . N '.rlli I ,,..|,i,a. \ m lli llakm a. 'In... I Y iili- i Jin m .i. ii!i.,.ii- M an , I, \\ a.ln ii'.-' I..11. V V .-l \ ira im a . aii'l W i -v i.ii- iii. S i l i c . i s i. c .iii|.iii.a l.lc in hnc ,.a i ... au.Illicr III Caliiiiriua. ( .nuiccticiil. h i.iric l ni ..lii,,,l,,a. Illin,.is. kcnlnckr. Massaclniscii. 1Ml1' ....... x .-' '"..rk. Nnrlli Carolina. Xnrll, Haknla. I lln.,. lY im .i Ivama. \Y t-l \ )r. m il and W i.c ,>11,in. and |ms.iMy m m l.cr Slalcs II i l l In- s u r ,........ a ; j f ......... ia r a liv .li lirchnisivc mriiiMliniial-discasc IcBislalinn is Bureau of Mm"in1es. .N, subiec<r lIokernIl|i.rycricKiolnr..l Il s ......... lalillc In.iks n i h, .ri. late ill II,, I ....... il il lull lln* lies I tin .. . . U llli lilts .NN.iliNN ciillirnillltu. Inn. t*| ars,allied iiidn.lrialisl h a s Ilie miriie ' " .........r-an i/alim , al In .in ill ii:i,,,,,|:,. I.lll I.. -,.111 i . . ,, in nrd. r ' I... .I!. ........ ,l,l` ......... I*........ al . I n , a-, ha/anls i ii.id .ii. . . .,, id in i.ii i i n li a|.|.|i mi! U s . rim edial im a-ur, . a ll, iiiiniiia ,U . Nell m ea.iiii - 11 ........ e v i s l I ......a .a ,,u ts mie ..I lln* ,,,..-1 in...... . ,.i il,, .1111.1.u l.e mad. relaie- I., ilii-i nc, n ri. iie, U lu le llie -lale tills) law - and ri'auLil.u 'M 'b I ' " ........h I" -diea dn-l and r,*.,ilf< -ill. . . -IS N l-n i.n .,- I|,, . In .,1,1, I, ,, . i n i ....... eerneil. ill**-** m ..-I lannliai- m ill du-i ...% ..... . N* 1........ 1.1. l i a r .11 . | ........... , . * ni, II,.,, ||,, I s . all,ins nl la. -*. .,,, ,,.1.1.. dil-l nl Iree -ill.*.. f S i f l ) ,. I*, snail -I lia/aid In I,,*.,Ill, lih. ii i ,, I. uns lien* dn-l in n .lie d . Inn il,.,l ......... -dira dn-l I- I l....... .. In I.,.,III. Hill.* ' n i, ins. hi n n lint'll d in d n l i. tiii *m*i ' Mt.iihe-d in iih iiitr lt hi" ,. i|u.ii|iIk'' IIs* or It-** 'ouimiioiilv i,,r h'm;lli o l inn- Mu'o\,-|< tn ;im ||jtlivhM^ * \|rl* on .|ni h.nmtiiIn"* ;m, no k i ln t om need ,t i* I,, |,, , , td tluit will In- li:niHd h iii iiiiiii.ni hfin^* i* ohliut d te> hr ;iilu: Inch 'oiii eiiitaiioii . kind *1 >111*1 uiort' or h-*s t'onlinunitdy. I i*Mir Phdi|> Orinkt r. o i H arvard, a* man o i ilic Prcvt-mivt* l\ii^ini-*rin mill- if thr A ir llt^ivm - I-'minelation. P 0 4 b w in which iauta*tii- l.una^- i,,r kdhfid Be* ert ^t-mi.d t,, i,Uu h o p d duU containin little o r no silica. , T ill f--ftl 1 * ------ 1....... t : ii k ta rd s a rc not [ftWfVacd with subtle distinctions In-Iwccu daiuwitb 10 per r a i l and HI |.. r cent ` ni o t/. r pfKfcty when medical \|H i i* a re r htctant Mb definite stalcnn-m* a* to the com *toHlhto significance o i *uch liltrreuces. *1t would be well I* rrah /r that mm . MtUa in dusty trade* *uii r far more k m respiratory trouble- - i all kinds ihau ie m who work in t han air. I'hr \ i,h o ,, totoficmivedustiin ss .* am kind i* harm Wtlbcyood argument " fe ibould also lie reim niU-rcd that 11,<o f dust is In ii., lean- ii> onl\ W d in industrial >>il. H.ai ..,, l .,,,,,. ^rraution payim til; and . vm In re ||m4 effect o f hreallnti'4 du*l i> not nec- -y-# eoufiued to ilir Inii'j*. a* **nl kind* I iw!??****rC n ha\e (Ii unental iii allh wet on the no*e. throat, and hroiicliial M lt n a s Well as |m .ln ,. iK > the lieail. 2hM0cb.and possihh other internal oran*. dust may cau*r injury lo llie ^ *od skin ; anl -nue lu*l*. in *on- the perspiration, are al.M irkd with wtue barm to tin h. ahh >.i il,. , ,, n ,,, Dust Cuts V isib ility Meetover. heavy couci iitraihins )( j i W r reduce V*il,d,iv mat riallv. t|.j 2 % tudustrial .. . ........... . , hi.-h ht.i * 2 mounts o i natural are avail S r m which ariitinal liht .* u*,-,| ' ^ ill vi*illi|*| V due lo r (..,,<1 til. dtvrea* in under stone eirciuu*lauces, T5 10 75 fciU *ir more) i* likely to l ^***l*rially rn h iiiu g ehiciency and i rm morc frcrnntii ocrurtcncc o i nc(t^ * 0mPanied hy an inrrea*e in com- Ltooimitnicnts Som e du*is (coal, >|Un, and scores *f others, niin- t^uicral) arc explosive ami many Front the view|N>int o i respiraM rv harmtiihiess, a is geueralty stalerl (though acltially kmnvledge on Hus point is hy no means certain) that the particle sizes o f dust (such ns that o f free silica) that affect health ad versely M|>n entering tire lungs are tho*r that are los* than II) microns in si/e, ililYcreui Ihts.mi* having liiiVreul leas as m what the maximum may f*v-- 10 m icrons or K or n ami some sav that the harm really is lone hy pariietes less than 2 microns in size. ,\s against this, it is staled that filers o f asliesto* dust ;,s long a* 2DI) microii* have he, n ionn.1 m the lungs o f uu n. ami that midouht cdlv these long as|-s|ns ii|H.r< ,.x rrl,, | ;i| least some detrimental effect. Sine; a micron is only aloi .uc twnly- live-lhoitsamllh ot an inch, or inu. li smalle r limn the uakel eve ;m Nee. ii i* usually 'itnieil that the larger dust particles that an k- s.-en Ihmiuig in air. and which *ellk- out relatively ia*l are uol harm lul I health < erlamlv, hi* i* 11>| ;4S ||H. |a r,..r tide* that lloat in the air (sme 01 them IWI *r iiiiiiv- mierou* in *i/t ), ,1 prc*enl in coii*tlerahle tnaiitilies el.g the air |ia*sag s 1" the lungs, *o,m. h i,|, have ageiine* tlmt under orliuarv eomliiirn* mlercepl dust parhele* Iwfore llu-v can r.ach the lungs ami this dogging then all.* ih, *,,,all, r ami piofmMv im*l lanueroii* ilu*l to enter the lung* miimpetled. A ciminon-*eii*e opinion a* to hat eon'lilu le s an atim .'ph.-re *.. ,|,,*u (|IU, ,|,, s< prevention action *lioiihl he takm is that any atuutsphere in which du*i ,an he seen In Ilir luk.*.l . 1 , i , | . ,, ,,,,iv f,,, heallli hut also, at least in many cases, for stie lv ami eliieienev. I f the visible lust i* elunmalerl, min i, o i the invisihle *r prohalilv most dangerous dn*t w ill iimtm *tionahlv have also Wen removed ami very likely the health as well as other hazards much miniimn-d o r even removed. A fte r the visible dust has been icniuvcd. it mav le necessary, under some conditions or with some types o f dust, to make more in ,C i * ' ,.* i., 3<* 'Ju rn ty -sirth X alioim l S a f*'tv C o n ijn ss huiu.-itr'utl S u r s u u j S * rtio n S17 11 nut ti will proliahly lie licst fir him to Ik* advised ol (hi* lac! a! die outset ami given assistance in securing rehabilitation voca- tuuial (raining; after which he may return to liis funner place o f employment qualified to do some special work. In Ihisraseh lie given c..o. .an*.s' Iide.rat iIo..n.. f/o r reiemploy', l i e will lie happy Iwcans: he Wlu overcome a handicap and learnctl can still lie independent. investigators seem to point |jiat noxious mines m great will produce immediate irritan the upper respiratory tra d serious complications ol the* pneumonia ami in some cases nko"> loos on soldiers who were gasseil Industrial Tuberculosis-- A Public Health Factor trorld war. made hy Met/, mdiIhyi noxious lium-s, when in- B y H. J . S P E C T O R . B .S ., M .D. |he lungs, lo not leaI to die of either anil- or chrmiic pul- A ssistant H ealth Com m isstoner and C h ief o f M edical Section. l^erculosis in most instances. i*rnm Olscrvalions the w ritcr is inclined St. Lo uis H ealth D ivision. St. Louis. M o. I f f * 'rid* ,his v*cuTM>ml The term industrial tulicm ilusis is some -nine abrasive industries, is die pn-wj lip o p c r Sanitation and V e n tila tio n what misleading liecansu it may lie thought that industry is die direct causative factor in inorganic lust i-n .,,, . .i ,l r 4lc,l l.,iu, , ' |^ |n jr ----- r * ~ ......... 1.......... *I J - the production o f lulicrrnlosis. I'.ui luU-r- laming alHionnal amounts <,f p ,, flf. ^sit Industries like hard rock mining, qiorr- io excessive moistures and working cuiosis is ; germ disease, direetly caused hv grinding and saml hlasiing havi W,H fegl p ro p erty ventilated ami unsanitary the IuImtcIc bacillus. NJo industry, no m at morbidity ami nioilalitv rale ir,, * N Ml VB expose themselves to the risk o f ter Ilow harmful it ma\ Ik- to the Immaii culo . i . i i ' J ,N^* L | i l f ibeir resistance, thus prrdis|>osittg IhmJv ui general, is capable o f direcilv pro . 4 lln lH .L .M .- ............ .. , I,,,,,!, d sued an atimisph re ou r i .l. v. ........................ I ,, *w . 1. , , ducing the disease IiiImt* ulois without die ........ ... ...... ,|| > ** " " "" r |resence of tiilicreh: liaeilti. Ctn.-r ill I,.1.1 ... the lie,.).. c I m UI and E con om ic F a c to rs How 'an we explain then the high nun I lu>H-iruiosis in mam iii-l.nice*. ... , , , . . lalily rale *r..ni luhcrciiloi m certain || k in accepted fact that tn b e ic n lo sis. industries ? \ sIk s|.,Ms i . a lis. a -e -m o la r t,, -a. 4 ha M infectious d isea-e. is eap aM c o i T o seek an answ er to this ittcstioit. one winch m av c o iiln h u le to tlw morl.i l.i. M a g and artuaHv ilovs prod uce activo tiiliercnlo-is. H o w e v e r d ie evidence .itno | S wIoms in people re g a rd le ss o f d w ir must consider die subject ot -o-ealied in ent m this d o e c iio n s not com im ii. J at*| md economic rank. I is a is . true dustrial tuberculosis from the broader as|nvl in general, hut c-|ieeially from the view|M>inl 2. O rgan ic D ust Id pam ty goes hand in hand with tuber- o f |Missilde e\i-iiig predis|osiug factors in aM a and that most IuIhtciiIoss will be cidental to certain industries. T h e muirihit- T'here It.is hem considerable discii- 4 w i > underprivileged pcopl-. lorv factors which may play a role in the I*i llie r*de ol organic hist in die prudikwa * f||| f i d has re*ciitly liecn confirmed development o f itilierrulosis are many in o f tulierciilosis. 'flu high inorlulin >4 Alktlallyby Miss Whiinev. who in a stmlv immiier. hut lo r die sake o f elaritv mav |m* from lulH-rciilosis in tnba*'co workers. 4* tfdnth rates by nci'upatiou reveals that the ciassilied under iwo main headings. f| ) w**rkTs ami tailors was u *|ii)iisilili' h ^ I -tiled worker, the one who u-ualh works eiiviroiniientai. and 12) social and economic. arlv belief that organic du-t was a ! hours and most often in a n u m entilahd Iribuloiy i.i* lor mi die pr<H|ii lioti MUtnilary cnvironmeiil. the om- win* Environm ental Factors mlosix. I he work o f Lambs i J 'lnl.i'Mi** ^*4% receives meagre c*m|M-iisahon ir ludiisirial ro m-nincnt has |<4ig In--ii rec ogm/ed as a most imjiorlaiil contributor factor in die caiisaliou o f iipjht respirator diseases. |'r instance it is known that em ployees in dusty trades, and those usually ex loosed I high temperatures, excessive moisture, to had weather conditions gen erally. and to noxious fumes arc among the workers who ircqucully arc forced to absent themselves from their employment U raiise o f sickness. ' wlii-li is Icised on aulopsv sludu's I ^ lungs o f .stf palieiils who had been n*r mane years ( orgauie his|s. tli-c*"^ this eoticepl sim e mmc o f lliC'C pat* showed -videncc in dw ir lungs of a** liiherculosis. ,\t the present lime i t ' * crallv Iwld that organic dusts do i`l p*"* disahling diseas- if ihe lungs au*l ate* predis|Hising facto rs in the <I xciopoi** * IuIhtciiIoss. , 3. N o xiou s Fum es i M n l f n , ka< a very high m orlahtv rat1 j * tuberculosis, flu (he oilier liaml. the who receive- a lair salare ami M i* HUily nut if tl.iors with little physi* MMftftioo hasa comparaliviTy hw hath f t l T t )uk the lawyers, the judges, the *ttd the maniilaeinrers. representathe higher economic bracket of so- JB tW ve the lowest dealh rales as seen in A*Mttajanying tabic. ^C fll^ .p tibiic health iutcrc-t is the fact nt, the cook and the waiter, 1. In o rg a n ic D ual One o f the most serious environmental factors existing, especially in the mining and The effect o f noxious fumes on the ami their relation to tuberculosis hal studied by W iutcrnilz o f Yah-. Met* U. S. Veterans Bureau and olberv u o f the lower economic rank, Hy high mortality rates. Since ` present frequent sources of community, the control o f I TABLE 1 Ovvili r a le s fro m tu b e rc u lo s it p e r 100.000 gainfully occupied m ales tS lo 0 year* o f age ill -e lrc ic i! s la te s av v o n liii lo rco iiv m te k io U|s . (I* Ml) Tuberculosis (R esp iratory Form ) A v e n u e , all iKCUpalions Averave. professional sm u p A w r.u s r. la w y e rs Hi jinhdcs )*hy-icia<s a m i M irgeous A verage, p ro p rn lo rs. mauaieers A oOieials H ankers, brokers. mone)leiM lers Muii.sKcrs a m i o fte ia ls R tuhlers, binbliug conlravlors Average, clerks & kim lred workers Kr.il estate agents Average, agrivnliural workers A verage, skilled w orker it fortiiiau M oulders, tounders, asters N7. > * -20.4 t M 27.* -tl . l .2.1 2H.X * ' 712 l" i I'nli- eiiicn Average, unskilltvt w orkers *i*" isi| F a c to ry A lo n b lin g coiiiruiin la lm re rs 221.7 A verage, vcrv.uit lasses * S ervants & cmiks * W aiters IuIh icuIosIs in this iTiniumic gnm p hc iima m ajor public In alili probi in. M iss Whitney's study was basl on in*r Ialite siaiisiics o f males onl\. Smw in-igbl mio ih: mnrhidilv accnnluig t* >* niMlton an lc hal from a r*c*m -ludv dial have math: in tlw St. lam is llr a lili Ih-paii ,, ,, n i mi 31.Fid n a|M*rtv<l cases of ttilwrcit |o>is male and fviuah- as - n il nm ih* vicw|H*iu( t>f occupation. \Vr found in Table II dial the ocupaiiono f IM.I.W or (id jht cent could lw Lis>ili*l umlcr Id m ajor luads. while tlw rnnamuig 12.551 could lie classified under i1).' ihvuim - It is imeresting lo note that *Tioii' T A B L E II S h o w in g *k u p a iio iis o f .tl.'W d rep*riet .io o f ........................ e n y u f Si. I.oiiis t l ,,M* f * 1 MM 1.1 T o i.d N. *( l 'u U r o i h o i '.e U .'i'in |'.,i No. of <)<eii|*alion-. 141*2 u f f a s e in I m a jo r eriipaUuM' 4 n i f u s e s mi i i'd re m a in in g m r iip a n o ii'. 1. H o u se w o rk 2. U nskilled taloir 1. f l c n v a l w o rk 4. Shoe w orkers t, Porters 9. Sttidenls 7<AI * sit' 2111 Hl.l 061 ili S7*)l n r t:ri> < people in tin* le n inaior oreupalinn- e ith e r dil house work or handled food. Total 9.* j Dusts, Fumes, Cases and Vapors W EDNESDAY M ORNING SESSION O ctober 12, 1938 Assembling in the (rami Uallroom o f The Stevens Hotel, this meeting w as called to order by Chairman Waiter S. Paine, Manager, Engineering anti Inspection lA partment, Aetna Casualty & Surety Com* |Kiny, H artford , Conn., and Vice-President f r Engineering, National S a fe ty Council. Chairman Paine brielly outlined the session objectives, and then introduced the speak ers. Recent Developments in Detecting Hazardous Dusts, Fumes, Gases and Vapors By W ARREN A. COOK Superintendent, Engineering D epartm ent. Z u rich G en eral A ccident and L ia b ility Insurance Com pany, Ltd., Chicago In discussing the determination o f injuri* <hi> dusts, fumes, gases and vapors. I am 'ry sure that you are not interested > much in a meticulous di-tcrtaliun on micIi phases of the subject as whether the loga rithm o f the reciprocal of the hydrogen ion should be 9.5 or 9.0 lor the determination of lead by the dilhizone method, hut rather m a discussion o f this matter along broad hues, pointing out what h pcs of potentially injurious materials should lie looked lor. whether determination of them is in order. * brief discussion on some of the more iml*riant and common method-, o f determina tion. and interpretation o f the results ob tained. Working in the lark witlimit any mean 1 illumination where there may lie hazard ous conditions serious enough to cause los ot life or severe injury would lie considers most foolhardy; yet every day m at conduci cir operations in atmospheres containing usts. gases, and vapors which may caus< ***** or severe injury to health without be . W iug able to see or otherwise |>erreive the |HteiUialiy hazardous conditnm. Most gases and vaimrs can no more he seen than the well-known black cat m the e>al cellar. Som e o f tliem cannt even Im* detected by Mlor, though mlor is it-cll no reliable criterion as i> evidenced by the gas, hydrtigeu siillidc, which has a nuM hih>\toils odor hut ha-, caused many a case o l poisoning. Hmv. then, are we to know whether the atmosphere in which we work is sale or injurious? A re we to %\ait until we m-c the elfcets of uiihealthliil or irrcvpirabic at mospheres <m our men or is it not more intelligent to dctcrnmic. within the liinitaturns o f inotlern mctliuds and practical a p plications. just what sort o f atmosphere we arc subjected lo? T h e ini|M>rtanec o f having fa d s before us is well illustrated by an atmospheric con dition where a life could |>c smillcd out in a few minutes, even though the m>re com mon situation is where excessive exposures may require weeks, months or years to cause their injurious effects. 4 .Vi/;# 7ji/*#/v S o f t l y ( `.M./r. v. Ousts, (ases anti b'afors 47 lim it-in ago tin- nitMiili a |M\tUi .! <>i ;u ln.u oi-niiaxid' p o i-o o n r -. crow ua> walking limn tin* tumid o i a new water supply sy,t-ni *f a l oiinilniit tlie read* .t.iilal*iiils l a .iniph- in*.in h t r i m i n m g lb .i i Im.ii iii*noxi*l< city. Tlioir lulv a * In inspect die root ami the iacc. to h t llial all lit* shots were tired. On apprMcliing tin- lininel heading iminetiiaicly a itit the blast, thee ioimd licit living rock hail hrolten the compics-.-! air line, which hail U-eii leit liirneti on m orl*r to blow the smoke anil gas away iron dulaco ot the lunm-l. Tlie crew. cnnsvi|m-ndi. ran int> a heavy blanket ot smoke. Imi iln-v were hardened workers. nsvd to moke ami cas. ami a little smoke, eeen thoii-ah thv knew it contained rarltoii ntouoxid. did n<<i bob! them lock. IralKMi o n th e p I'll- pi* m l tn*|. ii-, mi b'vt lopnn i:| m e th o d , o i <b : ......................... . inim itati mj le r ia ls in air i- towal -n,i> -im p le. iiikL a i t i n e d e r n i . . \ . m . i m \ o i i k n o w . t| I ioaal.llllllt t at Ia..n Ml*ll,*Xl*l< lit i'lo t aa|. eral-, uierelx l<\ pr* " i n g a m l i h r biilh tr iu n e . amt eo iiip .u iiie a pu rple ca.|or whirl llrx e lo p - ill p ia - li n e a.I r.irlaon 1111*11*.xi|. w ith a .|.u n la id ***1-*i .cal niaiiuili-d on iJ. in .lru iiie n i an >aperaln-u w lm ii iea|iiu. .Inaiti a iiiim il, lii.t im in n i. *.i lili , iv| at e .p n ia llv im p ,.n a n i i ;.a .e . win, T h e y IihiihI the m u i intact, lint lour o i mar c a ii.e .m il -**i.a*iting -urli a . o . the luiles hail not lirctl. I'ap s with i-tooi iiioii<>xnl<. In*lr**;<n i\.m i<l<. and l\*11 **-^er tiise> were inserted in sticks o i dynamite, one tor each ot the holes. The s;;i' eoiuli lion by flu* lime Ibis work hal It -m uc -,*iupl|.hcd was iK-giimnig to in.ikc d u - men iei'i a bit (jnyi:y. hollow im: lb- usual pracii-. the (mviUr ioieiii.ui -Ml llie ie-1 oi the men back down the iiiimel It ion In- hghlcd the illses -llipllfh \ n iii'tin iii ni <le i i n i m a l n >n o i |, ali,*g-n i r a n id a .m i l i a r (a. tin- lh * o l.in i: <ai In>11 III all*aX!le ll<i 1*1 . h a. ICC liti' laeel dr doped l.( Ilie I liliali N a t .. !:: n a ti al Mine wrkef'. and, lar.-edur .->1 a niiniher >l .*llir .I die. .nnpii- |et> I- I ll<> av.tli.|i-le alili'i>I:.til X Is I Ik- men walked back dnoiigli in .m,*k to tit* ar. alMMii a <juarnr >>< a mil- down tlie llimiel There tin- waited tor Ihe im r man. s e iiiix h |>assd The lime 'Ireteheil l> minai ion >ai -in ti Ii.il<i :.t- an niglv mad m u ,:, n n .i. w id. K ! . i*tiii i I\ w ln n l a li.r io ii. il t i m n .il lahoi.i 'i i n n t h o il- n i f i i n , .- a i r to a immiic. I town the tunnel came the Imnuii >1 tin- blast--but no ioreman. Tlie melt rii'iied to tin- beading and iotmd lli< iorem an stretched on the iimnel lU ir. nearly covereil with rock irom the l|.i.|. where he had colla|i'i*i ti*in tin- <He|. the caiboti monoxide T h i' I* a true 'lore up lo a ttiia m |*iin. but I have omitted a )*ait I the sfir\. and the m tliiic. I am glad I s u . i- pur- liciu-ii ilu part the story wbicli I onntlid u,i> that e ar:>n monoxide determination. being l.iKell wbeil llioc men g*l up t>. tin hc.idiug. an! a concent rat nn ot .1 per cent carlton monoxide was shown to lie presem by means o i the llookim iie curiahi inoiiox ide b-icctor. W illi micIi a Inch niicmti.i lioii. it ua<. realized by the man m.iktog the deti rnnnalioiis that it would iioi lake long tor c\|>o>el |ersuiis n collapse. He in formed the crew of the condition ami hur ried them back to the car to w ail uniil the smoke and gas had cleared enough to per mit them lo work safely and fire the Ida'l P otem ially lla/artlous M aterials I ha- l l l - l -I ;. Ili .i n aia u ;i | i i / 'd MU . t i . lo .o o i .l <m ir,.imi n i,il *n*hii..ti. ,\ii:, ma cau-- ,ii|in > i,, I n a lili i . a li.n iig ..i a, mai r ia l.. u.a| ..i p i <mIii, iI. u lm h ;.*- m,*lai arian i , ,.n > liiioii. la, ,|U 1naaii - I w . | . -IIII,I III .1 > ll| .| \ 1. |j>. l i n i , a| X . i l t - I'iiMi, I I ,a lili > -i\i,t ai p ..i,n tia l )i,*,.n.| m a iv p x .il m -lu -lii.il a l i a H .) llial a >,-li i*li.i!al, pvi'* iiia g . m ari i l i p< r n i, rii,- w .a r k .r . n i.- xp o.| pot, lilia li, i- - I I I ....... n -a.Ila. v i l l i fila - I T p a i l l II ||aa III, . 1*!- iiit m.tt I that i Iti - p i-m ntau- o i ori.'* vre Im-iii:; | hi|.< i||-i| l>\ .i i Ihiii m oiioxid l'Ut ra lh er that il thim.-. wnl rong am i i c o iic c iilm h o u at ill. - g ;i. built IIII 1*- pl'l l|MI lla -II. | b , M- .,,.I ntc |M.|.,ani 1. lip ! m m iglii 1 S o 1 .u g g e .1 dial x**ii g o ihr Oligli 1all' plants anti . whal opiaiiiiis mdt {hi .. tcntiail m iu n o io m aterial. O i the du-ithose vhich may pcodm i- .ihisi. u'cnr nit* only in the well-known industries where l l O l l i r . l l l l l l l S o i r o i la l a l la il l. h i l l - Ita-t-l! i i III' T h e difference between fart and fiction m this case, between a brief delay and a fatal dtiritMl but in oihrr uidusirtes as well, though usually to a lc->-r extent. In silver udfc- *';**., l* ware manufacturing, tor example, one man may be exposed day after day to tri|ioli dust in making up a polishing coin|iuiiml fur use within the plant. a\ list o f indus tries n which such dust cx|M,surrs may exist is given in the report o f the National Silicosis Conference.* The toxic dusts amt iunn-s are more readily spotted. Wc recognize and guard Against lead exposure in storage liatlerv plants, but often overlook such an iperatinu a where red lead is lieitig mixed with a vehicle by a worker in one corner o f the top lloor of the plant to color lettering on a strel part. It is not so much whether a potiml of lca<! or a ton is used in a day, lull the extent to wliich it contaminates the air breathed by the worker. Carbon monoxide, Indrngrn sulphide, hydrogen cyanide have Iteen mentioned as examples o f gases. 'Hu- first ot these <tceurs where producer gas or water gas is MM-d. The last named .iiotild It looked for where fumigating may In- d>nc irom time to time. Where dry iee is tt-cd in piantitv r fermentation |>roce..e. are >oudiicieil. carlton dioxide is liberated ami h;t> caused h alh s usually at the ImUoni ,i coniiite*l areas such as ships' holds and fermentation tanks. V.|H)r> are pre.eut wh-r\,r organic d-nts are used. Heath may re.iill r|iiickly where high Cotici-niralioii. v i.I .s has k urred when a drum o i solvent a. droppe! on a hasoniont -torag* room ll.Mar ami .plit o|H-n. and again liete carlH.n u-ir.iclilondas Itcing used for iiumgatiiig a tbmr mill uid the fumigalor .prinl.lcd tlie ii|tiid in the basement as In. Iasi operation. It a. bis last. Injury from continued exposure to sol vent vapor at ,o ii,,n tra ln ,n . which cause ihvir eiicet alter w--k. ot i-xpo.ure is the mrc common c>n<lition. The various solvents dilfer wulrlv in the ermcciilratiou of vapor necessary to eau.e injurv. These xre divided into groups in aceordancc with heir toxicity hi a paper delivered lie fore the Northestem l'n iv e r'ily S\m|s>.iiim on hciipaimnal Oi--e.is-N a -ar ago.* Where Shout, Determinations B e M ade? A fter going over your plants and learn* log where potentially hazardous materials it is my suggestion that, before ^ [actu al determinations o f concentra* lions in ;ur or iiistitiiting c,aiili*l im-astire., yu m ake a thorough survt-v o i the co n d i tio n s am i divnlc the varioii. o|K'ratio n . w h e re th ese m aterials ar- present into g r o u p s : (1 ) those hicli a rc o h v io u .h s a le ; <2) tho>c which a re adim ltcdl caus ing injury to health o r are worse than good in d u stria l practice dictale>; ( J) thus conditions w here it is not readily discern ible by general ohscrali>u w hether the exIKisiirr is within >aic limits. ( `crlaiu conditions we know defiuilclv .1111! can s^y d efiu ilcly vill not cau se in ju rv to health. I would nt sav th.it those are lo Ih* forg otten , hut at least iln-y mel n*ai Ik* the su b ject o i in itial action. I i. fair e x am p le , a g a s containing .10 r 10 per ccoi carlgtii m onoxide is used io r hoi plaii-s. am i those hot plates a r e nnected witli rie n l conduit ra th e r than xxith rublH-r till ing, y o n can i-d reasonably ..nV that ilncailHut m onoxide cxjK isu rc j. iihiu .,ii lim its, and I w ouhl not ro o m im u tl that h 'li-rm iiialioiis Ih* matlc. W h ere *pra p ainting is In-mg d one in a ell v-iiiilatel IhhuIi in siielt a m aim er that lh-r<- i. m, cx*-ssiv- rebound ml* the tucc < tl. sp r a y e r, leterm inaln-ns o i v.i|Har .r pig im n i ncel not he m:ile even though the nlor o i ih* so lve n t is d e le ctab le |-r**in tim e 1, lim e it m ay In- -II ir state au thoriiu -s to 4'h''k so m e I these U-s.cr e\|Nsur<` s, bin ib e re is a -nisiderablc iiiu iiInt o i .u c li x|Hsures w hich can he accepted its .ate . T h e second group o i -x|Hsiir-.--dial here 'omiitioiis are aclmiin-ll .ever---i. another here dcl-nmnaiion. are ui c seniial. htstiinie control im a .iin . inmili alclv. I f there arc cloud, o i Iii. i contain iug tree silica in your pl.mi. :<> t* ark >.n them. I i excesxive leal alot.i pia.aii i-. .|iown by dc*clopmcnl o i . mpioiu. ,.r by high ba.opliilic aggr*gati'*n piTccutag--, rcluce the l-al exp,.ure. It may be desirable t> make ietcrmiiiatiiuis even in these cases either t> provide a hei>rc-aml-ailci* picture o f exposures to shoix hat improvement ielTeett-d or to obtain a clear picture >i jut vbat pari nf an operation is res|Huisiblc ior the excessive exp>'ire to the end that con trol m easures eau be more specifically a p plied. T h is latter use o f air analysis data is o f especial value where the materials are invisible as is the case with gases, vapors aud even some o f the more toxic dusts such as quartz and lead. T h e principal use fo r determination o f 10 Silver Juhilee Safety Comjrexs '(liic (or am diliicullics which have been encountered. I cannot conceive ( any re* hahilitaiion w orker, a lter having '|K-nl con siderable lime in studying, analysing, and lraining one o i Ids clients, being willing to diru g Ids shoulders and say to the employ ment otiicc. "T h ere, now this is your prob le m "; nor can I imagine any employment service w orker terminating Ids interview with a physically disabled ihtso ii with a remark Mich ;i'. "W ell, you're crippled; the Slate Ischahilitaitou Service will have lo lake are o i voo " T o ine. it will alwuxs bave lo 1 ; rv*|WMisihihly ol (olii agcncics ami and mcaiis o i diselosing opportunit Miiiahle employinent ior th phv mali, ahled ean. perhaps. Itesi he siinmictl u| olTering tlns recipe: T o etpial piantitici a knowiedee o i th a p p li.a id ' .((itili lite |olt re|uirenienls adii ati unlur- amonni o i im tialive. per'cvcrance, uut! coo|K-ralion and hard vvork ami Micce** Ih* assnri-d. ^ ^ Occupational Disease . 1 THURSDAY MORNING SESSION O ctober 13. 1938 lo r the diseussioi M i* N | problems in the held of tip.1- jlt t f was called to ordir hy lite C " f . J . ngsten. Chairman, the Illinois |>1sdrill Commission, Chirac*, who pre sided. The Chairm an rn ip h u si/ed I he imIMirtame o f the selected s|||j-cis lo In* pre sented by eimiu-nt speakers. and |>rmipil\ intrmlnt'ed the lifsl 'i-hehiled s|i,-aker. .l/>7f>(//x\Y.W/:.\T The Trend of Occupational Disease Legislation B y H E N R Y D. S A Y E R Manager o f the C asu alty D epartm ent. A sso ciatio n o l C asu alty and Su rety E x e c u tiv e s ll IM Consider th e d i li e i.n .' between $4 Tridental injury and ...........vupalional !* For these distinction' aic mipori:int ^*1 *mi| constantly l*e Imrue in when oHiilcr either legislation mi die stih- |**l 1 disease, or engineering methods of or control. t l-nrrally speaking, accident' m n ir ai a | it*- >V moment in point ol time. and. from I iMidpuillt o f fixing p-thy ol insurance, it is liahililx under auv in the future; that h i*i ay, at the moment of the aveplanee at itohdity under any iiisiirame vouirael A* vident for which liuhihlv mav U- as- _ li^ not yet happened. Thai ir* il not so with the oeenpalimi.d disHm Inuirance by its verv Mature can * * aume liabilities that haw vet to *** Miot those that have alreadv accrued, 'n , speaking generally, the mdii'triul |y something that can he seen-- **J though unforc'cen. It max he visual- **d described in words. M-tling forth J A lk llly the time, place and mamiei id NHnlng. ^It can then Ik* determiued. alter bAppcmng o f the event, whether it was ^ U U b lt or inevitahie; blame, if any. can the worker involved, or his ,,superintendent, can he shown effective measures can lie rd against a like future hap- Itnl '.inc w ill '.(>. 11 ill \ . tiol all a c c id iiil' hapiM-n in th e m an n er d e s c n lic d ; ih a l not a lw a x s are l l n v h eld t>> o cc u r nix .il a '!*iti*' m m ueiil or u nder ii cnmMan w h en : th ey can he v i-n a li/c d and d* -i id>e.| Iv a d m in istr a tiv e and co u rt d t-ci-ioii'. il >' t r u e i n mm u e i t i r i s d i c l i o i i is d i a l I h e i 1 l n i i t n . i l o f " accid en t" h a s h e m g rea llv hrn a d .m d W e lin d th e e n tr a n c e o f d i se a 'e -1 r im m in Mm- h u m a n s V ' t e m w i i l i n t \>-M e 1 r a iim .t . W ith IT ' lil t i n g > ic k m -'s o r d e: ill . :H id e v e n ( l i e s p e c i f i c t i m e a m i | d a e e m i l <J e l i n i l c l v k n o w n . ' s e e p t l l i a t if i s -h 11VS11 t o h a v . p r o h a h l v H V lir r e d in t h e e m p i . v in e 111. h e i l i g h e l d l o 1.c a n a n i d e i l i <1Itt-r-v s. H u ll, i r s 1- i>>. ; h. I l .7 . a t. i . h Im :.S .>-: \ ... it . \ . w 1*. Il Iwr t o . IM W o . t m . I.....I . *-. ..I \ V ......... - . I 'o I ' oim im : o f t h e h n d v d i r . mi.u h II ie e l u v i ' . .1 a d . l . l e r n . i l ' o r l o s e C -M b ' l a m r u - . l n . t h e e m p i o > m e n t , l l i c Ian " C l's i .1 SS IIli e h w i n u n k n o w n 1 t o t h e w o r k e r , th e 1m pl. n e r h a v ing Ik-cii n e g lig en t in 'a ic g iia r d in g p ro p e rlv thc use o f such s u h 'ia n c c . ha Ih-cii held lo !h* the result <*f an in d ti'tria l a .v u lcn t. i V u l u i y S|> atkli-r S | ii.ih v '> li.iM ik*. 147 M arvl.im l. .li.S; m l Hie . rv r.-e^m >-m- Ilf Ill.VCk V ' t f C 'I.M I \ l l l l l I I I . lo w >.( HO t'o u r i , A mkM'I 5. P).t. JM1. N .W . S' * And where negligence o f the employer has been shown, an injury to health, even though not occurring through a happening at a given time and place, hut hy repeated 211 (^Industrial Hygiene Industrial Dusts--What Every Supervisor Should Know By L. E. HAM LIN. M.D. (Medical Dtr., American Brake Shoe Company, Chicago, III. procedures are capar varying amounts o dust TW viable. invisible, dangerous or I therefore important that these ? | , property classified in order j r t o health o f employees and pro- rironraaits in which they may fd a ily occupations. , t o supervisor should have o f industrial dusts since N ^ p w e ib iliiliuty for enforcing measures in* ( I * tthoe*ir control usually falls upon Lpp j h a l h l i Unless he has a good idea t o M t o risks confronting him, he will ' C I %A dvantage in securing cooiwratio ' Ml tndcr his direction. Ability to concerning plant hazard* f t t t M t o t a f maner is a very important t o k 'M y dust control program, and if ft* t^eTyhor cannot explain the necessity d M t o c exposure to toxic materials the t o t inner his charge is very unlikely to H ltBd h i to it t o t o Other hand, a brief explanation tol M fto t o ring of sincerity ami truth h i ftV|Mnt)y correct unnecessary mis* btiitohtf. For example, a capable ei plpytc was worried aliout cony N l Micosis because he worked in a f a t h er at times there appeared to 1 t o y e M l dust in the atmosphere, f Ic did that Utis dust w as free from t t o r harmful ingredient, but his his own department enabled P R f V n W to convince the workman * * _ t o t o y was the dust inert but also way for the installation r tottllating equipment which would p artic le s that were already pres* 1 Was satisfied and (he com* ^retain (he services o f a rasme o f the fundamental aid know about in* dustria! dusts? Dust is formed by reducing earthy materials to small size. Processes like grinding, crushing, blasting, and drilling produce dust particles o f sizes from the submicroscopic to the visible. Fumes are formed from combustion, sub* limation and condensation. Those from burning or fhelting lead or zinc are typical examples. The size o f the particles is gen erally below one micron. ( A micron is l / 25.000th o f an inch.) Smoke is usually o f organic origin from such things as burning tobacco, wood, oil or coal. The particle sire is usually below a half micron. Mists or fogs are formed by condensation o f water vapor and the particle or droplet size varies widely. The most important item to the super* visor is the realization that he may lie deal* mg with a dust which can produce bodily harm. 1 1 is first consideration should be " How is the man himself affected? Is the dust present in sufficient amounts in the a ir to be a source o f danger? Does it exist in the pure state or is it mixed with other dusts? What is the actual count o f particles per cubic foot of air, and what percentage of these is of respirable size (below 10 microns and especially those below three microns? How long does it take to develop occupational disease o f the lungs from ex* posure to dust?'* A ll this may appear to be outside the scope o f the supervisor's activities since a fter all his job is concerned prim arily with production. However, most industries place the responsibility for carrying out safety measures on the foreman and it is apparent that his department w ill suffer i f these are not properly enforced. S a fe ty therefore in cludes precautions against occupational dis ease as well as accidents so that some knowl edge o f methods for controlling exposure from dangerous du*is, toxic fumes or other 56 industrial Safely harmful materials is a proper pari o f the supervisor's armament. It is not advocated that his duties be so expanded as to encroach upon the field of the industrial hygienist but it is reasonable and logical to suggest that he equip himself with the essential details concerning occu pational risks in the department he man ages. This information can be realily obtained from his company medical de partment or through other agencies such as the Division o f Public Health o f state and federal governments. These bureaus wel come inquiry o f this type ami their services are usually available without charge. Much confusion and misunderstanding exists about tlie capacity o i various dusts arising from occupational procedures to cause physical disability. Exaggerated re ports and misrepresentation by individuals unfamiliar with their specific properties have incriminated certain materials known to 1 'quite inactive and absolved others proven to possess harmful qualities, Expe rience accumulated through years oi inten sive study ami research indicates that the great maturity o f industrial dusts have little effect on health other than their nuisance value and contribution toward poor housekeeping. However, the fact that they are unlikely to cause occupational desease should not lie used as an excuse to do nothing about them. A good working environment demands that they be removed in spite o f their in nocuous characteristics and the smart super visor w ill do all he can to accomplish their elimination. The wide assortment of dusts met with in industry makes their classification into "harm ful'' and "in ert" categories difficult. Those arising from organic sources such as animal and vegetable products as a rule do not cause serious harm hut are capable o f producing local irritation like dermatitis or skin rashes, dental conditions, and in flammation o f the eyes and the mucous mem brane lining o f the upper a ir passages. The m ajority o f harm ful dusts encountered in manufacturing processes are inorganic in character. T h e specific effect on liealth varies. Chromium, cadmium, arsenic, and their compounds produce local irritation as do the organic dusts but they can also cause general intoxication i f present in sufficient amounts. T h e ousts or fuutcs derived from the heavy metals like lead manganese ran be highly toxic L - from ilicse substances has bec|^ for many years. * Recently .crioti* and even flfcT has been found to occur from beryllium and some of its com povSl another occupational condition C S "Shaver's Disease" has produced age lo the lungs o f woikcr Z j j fumes arising from the fusing *| ! * the chief ore o f aluminum, in th a turc of artificial abrasives. Generally speaking, the particle ih| 9 is most dangerous is in the range of g * to three microns in diameter. fL larger titan these seldom reach gq | or terminal a ir saecs of the lung gw arc filtered out by the "cilia" ^ | protective mechanism of the m q, j and large bronchi. There is alto m dence that particles below one-luff__ in size may lie retained in the lung fed ciem quantities to result in due* | means that the visible dust m a t " place may not be as dangerous a* f tides which arc not seen by the iui Industrial hygienists emphasise I also point out that although the m visible dust in the atmosphere in <ltfl|flfl of a certain job appears great, it <fcg1 necessarily mean that the workmaC | | haling significant quantities of luudj| tides. The exposure may l * iiiIi i m r and of brief duration, or liie nr f l l breathing level of the cmplmre g | | sufficiently d e a r that no undue nd | l voiced. *1 With the exception oi hcrtll#' bauxite few of the aforcmcuti** cause damage to lung tissue j 4 l l plained previously, not every pert exposed docs develop occupatwvul I At the present time it is gcncrilbg that the most important sources el I trial disease o f the lungs are combined silica and asbestos. S W j silicon dioxide which makes < maicly 60 per cent o f the rocks and* o f the earth's crust, is the specific* the ailment affecting the lungs of fQ in dusty trades, known as silicon*- M It is very important to recognu* that this widely known condUi#^ be acquired from any material < Indutlriui MygUnt 57 that it happens only r than ten microns in have been inhaled over such as from two average* o f ten years. llQica'* usually means quartz 're many varieties. There o f free silica, r fibrosis o f the lungs the action o f uncomhined jtcristic nodular shadows itgenograms of those a fthis is the only way the detected as it causes no early, uncomplicated stage, produce x-ray (citterns to differentiate front sititmrdated U n cles may re* j . The x-ray picture ob(ht inhalation o f iron oxide Some welders and grinders __ which are ail too oftrn 'flftb o se seen in silicosis. Since (siderosis) is harmless, the ___ g f such misdiagnosis are ob- M h lfc y th industrial diseases of a u n v osc charged with evaluating rflJlINfirfar has resulted in 'employees lie- M W U lly alarmed, forsaking their II I fliforfeiting seniority while industry W l M I N t workmen and production. h lias also paid unjust claims for disability. In a situation o f this sort (lie supervisor suffers along with the rest since his de partment is bound to lie affected by these conditions. T o attempt to tell the supervisor all be should know about the extensive subject of industrial dusts is au impossible assignment. Suffice it to say that the more he learns about them through his own volition, the tatter his qualifications lor his job will be. Through such enterprise he will enter a new field of endeavor and discover a fascinating exjierience which will pay dividends both to himself and his company. The complexity o f problems which con front the director of any department in today's exacting requirements presents a formnlable challenge to his resources, and this, along with the working man's reason able insistence on a tatter place to work, demonstrates that a knowledge of industrial hygiene mav well he a most important factor in the efficient discharge o f Ins duties. The tast treatment o f any disease associ ated with industry is not to let it happen in the first place The problem is for engi neers rather than physicians, but. regardless o f the one *n whom the burden falls, the final outcome depends upon the interest and efficiency of the man who manages a de partment. ional Dermatitis; Teamwork in Engineering t and M edical Control By W ALTER F. SCHOLTZ 1*9 *1'* Industrial H ygiene, AlU s-Chalm ers M fg. C o., W est A llis . W is. i ? bOcepted the challenge that occu[ f i * * o m tilis presents to industrial accordingly it can ta stated care and intensive educaoccupational dermatitis can J t t d great savings effected. Jfct institution and maintenance ires workmen can be pro- . dermatitis producing oils, The ideal control measures all along the line-- ig of the basic mate- fabricated part, today i$ becoming so cognizant ot the benefits of good preventive measures that they arc not only relying on the worker alone, but are seeking the team work of everyone concerned. Since the proof of the pudding is in the eating. I would like to state what has been done through a concentrated program of occupational dermatitis control and preven tion which si;, rled in 1943 at the West Allis w orks of out company. This concentrated program has resulted in a 74 per cent de crease and a reduction from 10.3 to 2.7 in the number of cases per million manhours of exposure. hiH ustruil S tiffly /.t.hi.7. ..(/ //., ml< Table 1 continued IVopyl .celale ................................... 200 Tt*ir:uiilornclli;mc ............................. > Tctr:u-iiloroelliyk*ne (jxTchloro- ethylene) .......................................... 100 Toluene (toluol) ................................. 200 T richloroethylene............................... Iflll T u rp en tin e ............................................ 100 Xylene I nvIoI) ................................... 200 Table 2 Some Common Solvents and Their Relative Volatility i a s ih,- v o ia tilily iW . m INiT iW > V| v/.wi.v I '.i.iltlilv //.. \etotie .................................................................... 21 \invj .. -air ....................................... 4 \invl al-- hol . . ....................... Ih /iii* . ............................... 1.5 l-rilv! a'............................. r.n\i : Ij.>1 ......................... * :rl-.|i !i>uliiii' . .. .............. ..ri h I. ira- hloriil-................ Mr .............. I *. I.l-r- -thv In.- ....................... . 2J 10 . ir * l-ahvl a-aiaii- ........................... \ I ilivl -Ik>1 .............................. 14 i.ilivt.ni- -li ill*ri*l*................... 12 I i l i o r ............................. 2 Mi!;-.l a eii.n r ........................... 20 Melhvl alcohol ......................... IR Melhvl **hy| c lh c r....................... Vtphih.t (|H*ir>l-Miiii .............. P Pr..|.\| ..-lat*- ............................. 10 I **r.**:! *li;me ................... ,x lMa:::- r il.viene (|rrliloro * ili* l:u-1 ................................... 6 T lume lu.|> ......................... 8 Tri-til*.r- -vl*nc ....................... 11 I'm I .............. ............... . t \v irile * XVl>|) ........................... Table 3 Ventilation Kate Design Data fa a Number of Common Solvent? >e Importance of Non-Siliceous Dust in Industrial Operations 5*4turn,* u eight < Acetone .................... . 5H Acrylonitrile ............ . Amyl acetate .......... . LUI Amyl a h 'o lio l............ Krn/ol ...................... Isiil.ittont- .................. . laitvl acetate ............ Ho Univi al uliol ............ . ; I Ihllvl I ello std ve........ I I S t a r i.h li-aiHitlc . . . . <`arl-.n tvtr.iehlornle. * cllo-a.|ve .................. t ellosttlve acetate . .. t'liloroioriu ................. <'>clhe\ano| ............ t 'ycli>he.\an*ne ........ I >ii-|tl.r<ileii/ene........ ................. 11\ lena- c. By HOWARD J. URBA N jwtrial Hygiene Eng.. Saranac Laboratories. Saranac Lake. N. Y. ............ concern related to i|,c health t# IwVtrs in mining. 1111. 11-111r117 gmnitc * foini-lrv in.ln.irv- :m.| jn p * *trV - " call<l1 trade." for in (lie past. I n . liern f.ir the - f the wnrlvrr. from breathing -- particulate m ilter. irh m c a . ilic m u lt of their ncrtijtaiion.. which . . Ouse disease. ............... It m-rnrs a . ert.lallm e form or a . rrvpi, rv 'sl.'itv. linn, rliert or ja.|irr. e , 1 !', |. l ' ' 0e ,,iKl' ,rn,Perattirc rarirlirs of S ", * f TM -s,Ik `> are Tridvm ite which r t .t l l . from hcalmg above 870 d c ~ rrr. C 1 C r,y k t c from heating a l.,vr t47fl - AV^Vt S- r.Vorn shown by Cc<e'nn.rrt,1iccm.iuicraall .shtu,dj yy * * y i p t h i s a r y elemenl. make it|j 0 ))cr J * I k earth's c n is i~ il,i. i, |a w d on S T T T ". as,,m ,lion f-.r The ,, ,, h r ln dHalthieknes... In The ..r,l.-r ,,f th.ir 7 * * -'rc . ` .'C e il, .ilicnn, altttroo. magnesium. cal.-ium. <.,,|,llln e , " i i do nccur inthtstrial ,,rnc S f " k r t involve high tempera.,,res' i nT "niiorm ,mn,,,-r .era , ' ' ' '" 'i '1-- ' .1 the att.tns ,re t.tr. S ! " r" rl" l,av' omi as `Irlinile ,, rllc. ill- e h " 1' V::r,C,iCS " f l l ori-ttr. h, s Vy 'orlodcd natural dialn- (tielllt.iiHlIivI el her . I tiosaile . . ........... . . Ialivi acel.il ............ l ain I 1I. . I1. I ............ I 'tliv lene tlielilorile . Kilivl t llier ................ Melhvl atelale ........ Meilivle alcnliol . . . Melhvl ..I I----let . MontH-lilorolteii/etie . \ `a|t|illia (|tt Irtiletini) l 'crclil-rt-i-lli\ It ne . . Prop I acetal* .......... Prop I I...I10I ........ s'|otl-laol tlveiii ___ S iy n iie Mi..n<>mei . Toluol . .................... Triehlon-elliyletie . . . Tirptr*un- ............ \vl.-l ............................ Jh .Br^ascrc?1 "ht1*4d 7J 2y * Pdr" ccfenctl<o" ,fc" a'.ll "Mre-Kekcn. (S i) constitutes '8 w r Tlte H I * r t a l i ' ' <rTM en" . ...... >-- l-m ^ k tM bcen further determined tliat eight h i m "T V Y "'- A ' ' '- o n however k: nta.lc between the na.nral mtneral ," u vh e , fL 'n P aC<: '",l " ' C 'lia""o cen .,. earth ... S" " pl' t Of these A^Cw T!teV ?*.,rVTh!:e2wpnn.,ioinin`T1 6rn>,n*,'tn,,,",,<| oj.f Im an c SUM vvltieh ivettrs in S L " * " cm l o f oil r o .k . The re ^ W M m ou m |s are ehielly o si.l... ,, f ,|1C Omni,,|i. ^!Wn{s,Prc.v, ,islv tmniionc.1. *. t rr r ^ ... a*,. 2X ^ tn elal en ls |,l:ii,,lv 'die u.y l,u li f tth fo rm . ' T l lr!'n ' " ,x " lc in ** dtlnile h u 2 u J ri'*C ` c '" 'r *''='> as . ...............ltd. I r e r S i |. 1 retaining n s amorphous stair Iwmltru iiioo"- ^ L a syn'i,il!c ktf...i;m o ,, i,, g S ' r. itgthenutg cotton ll,rea<l. a M th.iii,,,c for i lam materials vt,lean,eel ,,,|.l r ,, ,, i ' , . ter repellent coalings for cloth. 4 '<:l T o v ^ " 'nX 8 f O' siliron (K , and Mollified. )lni^ oxitlcs as " silicates." ,ke chief rock forming llMndrcti sperics have hv h lm rato '11 rt<'0,!ni1Z" , <K <- sul.stantialed : . bU w -`lory research and observations in i>" !Ohleer ssp^ec!i!fiicfr"cauCsraytMiv:e<" ,a'g`'enstili"o f MthOe onaur.lr" -- ary disease Silicos,,. Further, it hat b ra . ...ni,;.,t p e a c e .. i,, llle consi.lcra.im, o f h, I ! '* n ^ w h k h "!'varic,ics 0( Frre siiiea. k ^ tnaitgaal a tm 2 ei Pre!M:nt n,orc -'ommottiy U w M a c 2 2 r pl'er" cn" l'1' ' f ,s.cd a. fcA r crystalline or amorphous. Silica ,l,c o '"TM* i e d uniform patterns giving .iikAlir t, ,w, , tk2o2t.,r,f;o,rrcmed at tern* lOotrees C and is the hiMrtuI dust ex|Mi.urcs which inv..l,c.l a silH.t harartl to imply that quart/ ,, a , present a; that ,, was the .............. ......^ .. I .-,It.taCrlimmnt,lhe r',aK'nkCm" ine" rKalsPof!*t-h"oeleeraarntehe and mir lack o f knowledge relating to the 1 " y o f " Silicon dioxide forms tl.it view was to be expected. Recent ,,u .l i ,, particularly those made at The Saranac Laboratory, however, have industrial S tiffly iHiluttna/ II,-alili //,,-or,/, demonstrated that certain varieties ot ircc silica other titan quartz, yet similar to quartz in -chemical composition. can produce pul monary lung diangcs in animals. These lime change* arc unlike Silicosis. In addition, clinical studies Itavc reported that diatomaccous earth, for example, may produce pulmonary dian gcs in workers inhaling dust and that amorphous natural dialomitr i* less Itazardous titan is tlie crystalline cristolialiie content which was formed suliscqucntly l.y high temperature calcining procesNC*. Currently nlisrrvaiioiis ate underwav at the Saranac t~aUralury al*, coticei umg the effects up* 11 animal* 1" |i1lut*! inhalation o f several of the new artificial amorphous silica*. These tndie< are lumluaiii in m o respects. Tlie lir*t relates to the particle <ize ami the second to the rh em i'irv o i llie-c new product*. One o f the earlier comprehensive studies made in ibi coiintrv . i d.c -i/e htnbuiioii o i du*i* iound in \.m4i uili'ti*1 cmin-nincnts \va* rrportvd l\ I I. Illoomliclil >i the U .S. 1` uhlic llea lili Service m 19.M. Some o i his work i- hown a- RctVrenec A on the slide. \ light held micro-cope sy<um will a magnification l I.OUII diameter* was used which allowed particle* as small as .5 micron to le measured and somewhat '.mailer particles to lc ceil. The data indi cates that the greater i*crcctage o i the particles were larger than 0 5 micron. 1!. I Green reported in the Transactions o f the Faraday Society in H.Wi. the data shown on the tide as Ueierenee 1. With the magni fication o i 1.500 diameters which Green ' ImsI. parlid** " I I inicii.il were measured ,.nd as small a* .2 micron were seen, ill data shows a higher percentage o i line par iah 's. Ies than .5 uiicmu in *i/c. Ilian doe* Ivcfcrcnec A , prohal.ly dm: to the difference in the magnification* o i the two vio:n* However, these data do agree in the tact that most o l the dusts observed were micro scopic in size, that i s they were .2 micron in size and larger. It has I>ccn the contention oi some invciigators that there is a limit to the extent to which solids can lie reduced iu size l.v ordi nary disintegration methods. This limit supposedly is imposed by the operation o f cohcsional or surface tension forces upon each separate fragment of material as it is being formed during the process ot disinte gration The lower limit oi p.irtulr >l/f. Bquid which chemically contained such disintegration aerosol........ `dm | 4 Tit* --liq*u--id w...a..s....c.o..m...b..i..n..e..d....i.n. tl:c wLaub- to 1 in the order of 0.1 micron. TM -- with a gas and Inirncd. The re Perlite is a volcanic glass. This pr<ifa ^ I m Iw s practically pure anior|>lions mined irom the earth ami later Mibjcu^i |M pfffl industrial processing sliows co m p an y ^ ( w en t photograpli which was pro- icw In'i panicles arc present which than one micron tu size. l p | Ig an outside agency, the primary y Jr k t t K very fine in size. W e think that In an electron-photo micrograph o i . j f pw |u|C spheres are Latex that had been liorne sample of common piartz ifaq y ||M I t the sample as a reference for size piartz had l*ccn ground ami hill-mill.-i* |MWWKflt Ju M m lly lo rnhirr il I.. line ifl X - n , diffraction |a<tcr,.. o f each of Only a lew I'..ruck's less linn one n o , M ro so ls show wi.le .liiTuse rines III M /C arc present. J n l l l f dial the materials are amorphous ft would seem that photographs h i || Ml crystalline in structure. On the to the view that the ordinary dtsmic-rjq Mt the X-ray the materials are indis- I. P an .clci as fine as 02 micron can ho brentlictf and rclamrd in ilic lunRS in ... ..................... l ,, pro<li.cc disease. Z. Forms of free silica oilier Ilian q uam can produce pulmonary damage. Aluminum pneumoconiosis, or Shavers Disease has been recognized as a specific disease, different from other imcmnoconiixr including silicosis. It lias occurred in baux ite workers, particularly those exposed to electric furnace fumes. An electron photo micrograph shows the particles to be much less than one micron in size. Chemically the lnc is composed chiefly o f aluminum and amorphous ilwa with possibly sonic glass present. proccsses in industry as crushing. ydihiblr but because o f the diffuse nature drilling and hl.istiug do imt produce -Iu-m# rings It is difficult from the X -ray silli-microscopic size. However, a.ldiu* determine how much, if any. o f the observations must lie made with the t-lwiM flbfl It each preparation may have liecn tnicr<copc to substantiate ih k ' pO m i U silicate with the metals present. TI,o .io m fn an coo t s,,l,n n . roK,a|.l . l , h ,, ^rtinen. ,0 the o.vK ri,ncn.al ol.- lo.ru. k-. is a sul.p cl w ind, re e m r. , - * * * , ,, ih the four silnas arc srnn- ,l..ni,..n in 11" ' III. ralur.-, II.c -- M iK AMlyMS ' o f ' . i , c 7 m ,." pr imil- ..... . lc,s U cn ,l' " I " " " 1 " ' j j P W * I A . B. and C s lu m o l H,.,, .,|icou enough in size, even ii thev arc Im the chief coiiMituant. hut that into lb* lungs they will not I.* retain s of the oxides of iron, alumi- will Ik* rsjK'Hcd with Ilie expired an Pesitim, sodium, calcium and |*otas- Four olcrvations have liecn coni|i<*11 ? ? ? ** *** Prcsenb Some moisture in The Saranac Lalioratory with dry - " combination with tlie silica was o i four dillcivnt bind of artm'Mi>< C sample and was rcmovnl |,y ducctl tree silicas. All the aero*!- l* " * *e corresporuling increase in total sub-microscopic in *izc. The partial s* -- !!!* '* in<,'caUM* Preparation A ranged from .02 to .2 micron. Tlie'* imm the absence of heat. D is conq>imd* arc identified as a--1--r silica. Consequently A and D Preparation was made by a cool I - i Z n f edy amorP,, "s Heating in the clicmic.d process. II, C. and I) '' ' y r i C*/Ia,n mela,s Wi,s required to pared .it high temperatures k ' * ** C. It is imlgcd that these In an eh'<`trou'pliilo nmrogr.iph - R a t i o n s may Ik- partly glasses or liict A, the primal y particles arc rs* cates. line iu >i/c with large surface arc In a photograph of Product I*. d-*' . Ics an: Mib-micriiscopic. Tl.s* bet T* lo have a lcscr leiidcitcy ......... aggregates. I'lmratory animals I jJ*1* * be inhalation of these four each day. 5; days ,wr week ycars/or longer. The co,,c " rations of the In iVoduct C. the particles arc umlcr one micron in i/c In fo ie ,r they tend to rcsembh: Product 1 in M Z ? * * * animals were uhjecletl I l f i S L i 6 10 4 2 mK/ c " H. On the i lP b o to gtcal findings A and D pro ap|Kar:mce, damage am] were judged to T h e fourth product D d ilu te d t*'^ disease produced w as i m like others m cveral rcsiK'Cts. A, 1. ,l" l ' prepared outside of the Laboratory **" , quartz. B and C were con live. to us in bulk for study. These * were then generated as aerosols by | disseminating technics. Puikiratsft * can be made from these have important signifiI dust exjtosurcs. Sk ivers Disease is another example of sulT microscopic particles causing pulmonary damage. Industrial environments which contain pre dominantly sub-microscopic dust particles or more properly, dry aerosols, jkisc a real problem for the industrial hvgicnist. I'irst: The particles arc two Miiall to be seen by ordinary microscope technics. At the present time cstimatimi <>i atmospheric concentration* must ut-cc at dv k* made en some weight basis. The proper r.dlcctirui of these particles may lie dilticuli. They ma\ 1. and some o f them definitely arc. tine enough in size, to |>ass through a No. II Wh.utman fdter pafier. Some because o f their |#oculi;ir hy|ro|diobic pro|erty camioi |,c wcttctl by ordinary liquid collecting agems. The particles o f one o f the materials with \vlucli we arc familiar, carry a sialic charge high enough lo disrupt the ofx-raiion o f the electrostatic precipitator. Further, and pi. ialdy of most iiiqtortancc. if the material has any degree of toxicity, k e au se o f the lino ness of the particles, allowable concentra tions of exposure will uccesarily have to he low. The collection m smii>i<nt dust to weight accurately will in itself I* problem. Second: The determination o f the chemi cal composition of these aerosols will require inorc detailed analytical work which will include chemistry ns well as X -ra y diffrac tion studies. Micro-chemical methods may have to be applied as the amounts of dust collected may be small. Obviously new and sjiccialucd methods both for the collection and analysis o f such aerosols will have to be developed. And finally, a dust control system to fit specific IK tntiu U r i/ S .ifs tv Know the Facts -- t r rciuirum m s which may U* different from ihos o f ordinary lusts must 1 devised. It niav appear that this <lirtis<inn Ins related mainly in dusts continuing silica. . ilm lv .I,,,.,,.,,, ......... ,l,r Plonvl Snell l:tn r< m.iy |u v t :is clinngc in particle si,, area, a irla rr ...alines, electrical', Most o f the views which have Item pre sent!, however, ran lie apidicd equally well to oilier materials, liven will sub stances which have I-cm cotisi.lend in liereiilly inert, it dmuhl lie r.rogn/d that certain factor may .|ieraie to alter this condition. R eferrin g again to Shavers disease, powlereil metallic aluminum ami hydrateil alumi ailsorpnnn ami air-... phn,, ip u l,,^ alter their U'liavior. Incre:isel production activity thnu vauce| im rh u n i/aiin ii is a signify-.^ in creating correspondingly knser o f dustim-*. I he experience in n mines in Kuglaml and m ore rermtlr country are examples. Carbon lu il^ considered inert, I'idm onary clime, Electrical Hazards Interlocking For Safety ^ By A. L. RIC H E M,Cr D ,v- M 'nn P o l " -H anyw el| Regu lator C o.. Freeport. III. e num have been used as therapcuii* agents in the control o f silicosis on the theory that particulate quartz is inhibit-.! by these materials. On the other hand, rrcent lab oratory indies intended to duplicate Shavers disease at the U niversitv o f Toronto have demonstrated that suh-micrnropii: alumina ly itself or in combination wiih silica fume a n i.uise lung change. A s an opimsite. wuh asbestos the fibres longer than 10-20 microns appear to c.ium: disease while the tiner particles do not. New industrial |r<tsv, an* Ining de v e l o p ! which utilize heat .md high energy release. In etiect. m w inelliuds *i disin tegration have I-ecu rrraietl. The diluents irrim eh pr<* mav have properties lungs o i c,al m iners have occurred authoritie- tcel th at Ih r carhon.i.ron poocut <*i the coal iiseli i* rc[|^ It would appear that the terms " ` hazard." >r "siliceous dusts" nrol a cation sim e >oine form s o f free ufe than q u a rt/ m ay I*- capable oi f d m reactions which arc different irom fc idion ! *ju.iriz. iiseli. *>f increasing concern in certain environm ents arc the sub-micro*,,, l , | tid e s and considerable research u4k j io lie lone to determ ine their , ^ \ m atter *i no small import io reg ard is th at diese -mall (.11111 . exhibit properties different from m aierials from which ihcv or-Mow* it with some words we'll be using. just a fancy word meaning Be thing lakes place, something . or something is prevented from From this definition, we can here is an interlock between M latter, better, easier operation tkctrk switches can produce. An ' Is a two-hand electric trip for prtss control. Operators have in.JJJJJI froduction as timcli as one-third, ' W f Itcuise they felt safe and the elecV i usilclia worked more easily ihan h'P*' This type o f machine * choice o i state safety comPN I^i iad insurance companies. ^ fHaaples of electric interlocks are . l*fo re driving jour car. Thai i . >i,,|, Tionjorgelling" nilcrlock. This uicim .rj-jogging use is just one t.i the ways that switches produce safety in some w ays they think fo r the operator, as well as act for his hands and eyes. They can make .1 machine refuse to run until , ,s or'!c r ; they can Mop a machine when something is w rong; they can compel Hungs to lie lone in Hie right onlcr. This means safety to the o|>crator and to equip ment. It can aho insure product quality. We sec electric interlocks and limit switches in machines as different i rm each other as juke boxes and automatic pilots ..n airplanes. They are in automatic gear Aa electric switch which turns on shifts mi automobiles and in dial telephone when your refrigerator door is U in example. c<|uipmciu. This success, for so many pur poses, dcpemls 011 well-known haic prmci Ij Iwitch" is another counnon term. witch which stops motion or when something moves to a A switch fastened to a lathe ' -- * ** lurn 'be motor when , coming against it. is a l b * Z 5 ? t use of li,nil sw ` ches to I h a w a l r t ? *rom damaB`ng themselves * * .,1 1 , . CVn,monest ami best-paying b (g 11 w ** easy to put on any I* dcsigT1 in' 0 new equip- pics combined with using the lest type of switch fo r the particular job. This is as true m working over an old machine 10 make it automatic, or 10 provide afety. as in designing ncW equipment. On either kind 1 io``' r ,,sc ol liir r` ght switch ran make H*c difference between a maehinc which Sves long, reliable, ale service, ami one winch is always in trouble. Three Fundamental Kinds of Switches ^ t y p i c a l of electric interlocks anti There arc three general kinds o f electric switches used in interlock and limit work. 1 Hm ? " *^*nis automatically -u^*>>|on 0 r r r " ll> >t-position 0r - , -Ma > l ,ey !" " f a prcss,,r^ Sfuge or * ? s,ir,ni device more accu- w.dnc by <yc Thcy re` and accurately than [ h i 01 ior*el- Neither are * what to do next. On A .t Uuiking light or the hand brake ,TI:' o,K 'on,!<;s, are moved without snap action. L\u y 'cl, C O M M , are nroun.cd ,, ,, |c."( springs. Another form uses liars on the face o f a cylinder which turns under fixel contacts or brushes. Their simplicity rec ommends such units, and they serve well to swjtch small amounts o f power when pre cision is not required, and there is plenty o f operating force and motion. Picking up your telephone works such a switch.