Document VjzbpBm3Vn9NZEgnja53pKzLN

FILE NAME: General Motors (GM) DATE: 1937 Oct DOC#: GM005 DOCUMENT DESCRIPTION: Transactions - National Safety Congress alsdl NATIONAL SAFETY COUNCIL, Inc. KANSAS CITY, MISSOURI OCTOBERS 1 to OCTOBER 15, 1937 Municipal Auditorium T ill-'. T r a n s a c t i o n s o i ( <>ii" i e - - , 19.57, a r c l dimcil in t u o volumes. t h e 1 vi i n i y - s i x l h N a t i o n a l S a i c l v ptibli.-hcd by the Xational SatcU' This, the first, contains the general, t he s p ec i a l s u b j e c t , a n i l t h e i n d u s t r i a l S e c t i o n ses si ons . '1 he second volume contains the sessions of the Child education, 1hune .Satety, Street and H ighw ay Traffic, Commercial V e hicle and Transit Sections. All-industrial member-' of the ( m in e d automatically receive V o l u m e I. V o l u m e II is s e n t to m e m b e r s b e li eved to be i n t e r ested chietly in the ses sions it covers . O t h e r Council m e m bers, h o w e v e r , nine o b t a i n it u p o n r e q ue s t . M a n y m e m b e r s have f o u n d it w o r t h while to distribute copies oi the Iransactions to supervisors, foremen, and others in an administrative o r supervisory position who u n i make practical use of them for reference purposes. The fol low m y q u a n t i t y p r i c e s ti re q u o t e d o n e x t r a c o p i e s : 1 to 10 c opi e s o f t h e Inrye v o l u m e ! \ o l m n e 1), $ 2 e a c h ; 11 e n p u or m or e, S I . 75 ea ch ; copi es o f the sm al le r volu me (V o lu m e 11 ), 75 c e n t s each. T IIF. T ransactions a re published as a condensed record of the proceedings at the Xational Conyress. The papci- of ea c h s e s s i o n o r d i v i s i o n o f t h e C o n g r e s s h a v e lyecii edi t ed c are full y to eliminate e x tr a n e o u s m a t te r and tn^ahhiev ale the less essential portions because of space limitations. Tluithe m a t e r i a l herei n p r e s e n t e d is not a v e r b a t i m re p o r t o f all the speeches presented at the Congress. hut rather an abridged version made as compact as possible, vet without injur)- to the technical aspects of any address. The oriyinal uiamiseripts are on tile in the Council's I'.ureau of lnfm nia turn, w here they are available for additional leferenuV he re illustrations w ere sent by the s peakers to the Council, tl ie- c a N o a r e on file. T he Xational Safely Council at its Congresses seek- to elim inate f r o m discussion m a t te r s w hic h are not pertinent to the aim ot the Congress or which are contrary to Council policies. It cannot accept responsibility for the views ex pressed eitliei in the p a p e rs presented or in the discu-sionbased upon the papers. NATIONAL SAFETY COUNCIL/ Inc. 20 North Wack e r Dr i V c Ch i ca g o y Council Officers and Directors. . 4 C o u n c i l P u r p o s e s a n d P o l i c i e s ....................................... 9 A n n u a l M e e t i n g o f M e m b e r s ...................................... 11 A n n u a l l i a n q u e t ............................................................................................... 31 Subject Sessions-- A f t e r W o r k A c c i d e n t s ...........................................................................33 A g r i c u l t u r a l S a f e t y .......................... . .. ................... 41 C o m m u n i t y S a f e t y O r g a n i z a t i o n ..................................................... 51 F i r e P r e v e n t i o n ................................................................. 59 H e a l t h S e r v i c e in I n d u s t r y ............................................................... 71 I n d u s t r i a l D u s t s .................................................................................... 85 I n d u s t r i a l F u m e s , G a s e s a n d V a p o r s ..........................................99 I n d u s t r i a l S a f e t y L e c t u r e s ................................................................ 109 M a i n t a i n i n g I n t e r e s t in S a f e t y ....................................................... 141 P r e s s u r e V e s s e l s ....................................................................................157 S a f e t y F u n d a m e n t a l s ............................................................................173 S a f e t y I n s p e c t o r s ..................................................................................183 S a f e t y T r a i n i n g . ,,............................................................................... 193 S a f e U s e of A c i d s ....................................................... ' ...................201 A e r o n a u t i c a l S e c t i o n ................................................................................... 211 A . S . S . E . -- F . n g i n c e r i n g S e c t i o n ................................................................221 A u t o m o t i v e a n d M a c h i n e S h o p -- P o w e r P r e s s S e c t i o n s .......... 225 C e m e n t atvd Q u a r r y S e c t i o n s ...................................................................... 249 C h e m i c a l S e c t i o n ............................................................................................271 C o n s t r u c t i o n S e c t i o n ......................................................................................285 F o o d S e c t i o n .......................................................................................................307 I n d u s t r i a l N u r s i n g ............................................................................ 323 M a r i n e S e c t i o n .................................................................................................. 341 M e a t P a c k i n g , T a n n i n g a n d L e a t h e r I n d u s t r i e s S e c t i o n ........ 371 M e t a l s S e c t i o n ...................................................................................................381 M i n i n g S e c t i o n ...................................................................................................401 P a p e r a n d P u l p S e c t i o n ..................................................................................429 P e t r o l e u m S e c t i o n .......................................................................................... 489 P o w e r P r e s s S e c t i o n ........................................................................................ 535 P u b l i c U t i l i t i e s S e c t i o n ............................... , ...............................................537 Q u a r r y S e c t i o n ......................................................... ....557 R e f r i g e r a t i o n S e c t i o n ............................................ 559 R u b b e r S e c t i o n ................................................................................................. 577 S a f e t y E q u i p m e n t S e c t i o n ..................................................................................581-- S t e a m R a i l r o a d M e e t i n g ................................................................................587 T e x t i l e S e c t i o n .................................................................................................601 W o o d P r o d u c t s S e c t i o n ............................................................................... 611 I n d e x ...................................................................................................................... 621 SfiSSBBBata' ife S Y E ia i c fllf Is a s . HONORARY MEMBERS \ " > ' n \ i i i > N ni I kon w o S u m Is. J:J ivi \ \ w h -hi t ! I I V\ K }' \! Ml li K nmni i in OFFICERS (1937-1938) P P F n s i .ii., P r e s i de nt C. \V Dl viri.sy. \ ' icc- f'r.--iftit 'nr Fi nance ami T r e a s t n e r H vkhy l i n i .111 KT, Yi ce- Pi c - i de ot f or Me m b e r s h i p F i; \ nk II. 11 MtKi'ON. V i ce - P r e s i d e n t f or I n d u s t r i a l S a t civ H on. ! ( \ k<>u >G. H o i i m w , V i c e - P r e s i d e n t f or Publ i c S a f e t y U' u. lii. ' S P u x i , \"i.c-Pic-iik-rU for F.r.yincerinc; A. Rollivi.In k. V i c e - P m r lent for Local Safety Councils A. \V. W tii i xrY. Vi c e - P r e s i d e n t f or F.ducation W. H C.wii.hon, Secret ary a n d M a n a y i n y Di r e c t o r ' E X E C U T IV E C O M M IT T E E (193 H. \ \ ", A m i i .knj N, General M o t o r s C o r p o r a t i on J. I I' vnsmi, P a - t President (.". W. Iti moi . t -v. Past Pr e s i d e n t H i s i a W. ioi.uisS. P e t r o l e u m S i t u m C. P- Hoi if 1, A S S L - F . n y m w i i ny Section H. W. P o n . a o s ', A u t om o t i ve a nd .Macinile Sh o p Section II Mini n S. lie 11r.Mi1.in, '1'lie A m e r i c a n City Mn y a / i n e \V. II C vmiko.s , Xat imi al S. t i c t y Council, Inc. Koiu.ki W. C wi ri u I.I., P.i' t Pr e s i d e n t K0111 tv 1 C m i .i s , Aet na Casualt y k S n u - t y Company K'. A. I ' m m i i n, M e t a K Seetiuu I. MYis A. D kP i.ois, Pa s t 'resi dent C. W. D k.MITSY, T l i e Liqui d C a r b o n i c Co r p o r a t i on M \m i s A. D o w , Pa s t Presidi lit I) I 1 FrNNia.t.. Consultine; F.nyinecr J ohn I! Gnisox. W e s t e r n Ll e c t r i c Company H skiiY Gun. 1:1 i;r, ddie Pu l l ma n C o m p a n y I'* \ Ns II. Huiiiisn. v, Intel nati onal H a r v e s t e r C o m p a n y P. L. G. H xssK m u , I.cbiyli Valley S a f e t y Council H on. H \ koi ij G. H o n man. G o v e r n o r , St a t e o f N'cvv J e r s e y S. H. Homi! 1.!., F o o d Section W v n i i i G. Is 1Nc., Pa s t Pr esi dent I II 4 OFFICERS A N D DIRECTORS, Continued W \i. ( k k.\ui i k, Milwaukee Sa U ty (, <mi mu "dun | n u \ LC Lom:, Past P i o d d e m I uns. H . MacDu NaI I), Ik S. 1H pa;'1iinil <>I A *ic/lil tin e \ \ \ ' ai ii k 1* M aidin', P e o r i a As soc i a t i on ol {'oni ,nerve Sa t\*l\ Cun I. \\k M im \ ro, Industrial Glow*. Company ll\Ku!i l. Miser, Is. I. tin Pout (It- N e m o u r s X; (M. P roe. Iv'H.i k L. Morrison, Street X !ijc;hua\ TiaiJtc Section 1C ]. O 'P rjj.n, J r , Louisville S a f e t \ (.`m i n n l Wu.ir.K S. C unt , A e t n a Li f e X Affiliated Co<. l a w R. P u .mi.i;, Last President C. L. P o nu o v r . Past Pr esi dent Xi.Ri KrS. ki.cta.A, industrial Relation*- Counselor-. Inc. l.i. Cot H enry A. Rf.vtxi.iR, Past president A V. RonwnnK, Duluth, Mis^ahe X Iron Ranc;e Railway Co tifoRf.r K. S anford, General Electric Co. C n u n i s ik S cott, Past President G w . John il S ueriu. rxe, Ma'**ackiwt(s Sai'ct\ Council Jt.tK.i. Ini: 1C S keee, Cleveland Safet> Couneil C. W. Swi m. Standard Oil Company i ln d. ) W. m.ti k I t t v r S mith, Delaware S;uVt> Council R. T. S oekNsTI.n, Elliott Service Company C. Ik T oe.man, Past President G>or<;k G. T racer, Gr e at e r Cluoa.no S a u t v Council, Inc. D r. C. H. W atson, P a D President A. Wk W hitney, National Corners alum Pureau Ik A. U ii ''ON, Textil e Section - \ \ . 1C W'oriu, international Harvester Co. Aknrt.ii 11. A ot;.\v,, Past President DIRECTORS (1937-1938) Giom.r J. A i m i s , Paper and Puli Section H. \V . A s m won, General Motors Cmp. A. I.. A rm'd rono, Eastman Ko<lak Company H. H. P miey, Chattanooga Safety Council J. [. P\N.\sli, Consulting ICi.t'incei C u t P vkkir. St Louis Saf e t y Council G. i. I'. muu it, Mining Section E rnest W. Heck, United Slate*. Rul i Ur Product*-, Inc. C. Wk PMu.ot;i<T, Western Electric Co. h. 1C Pi a n k, Jones X Laughlm Steel Corp. H inka W. P ocoess, Petroleum Section II 1C H o n . South Haul Civic Sa f e t y Council r F I CERS A N D DIRECTORS, Continued C. 1. H u m r, A S S L - L n y i n e e i ine; Secti on II. W. I'.urt m x . A u t " m o | ; \ c X Machine Si mp Section I*. S. H k n u s , S t a n d a r d Acci dent i n s u r a n c e Co. \V. A. I ' kdwn, Sa f e t y I h-\K\i i nn tit, Nashvi l le C h a mb e r of Cmn me i ce W T. I '.i i Ki k i n - a . Linpl >> t bi bl i cal ion Sc ction S. W I'.i m h i m . Safety Dcpai intent. \ u t m i m b d e Club of Kl uuC Gland I l \ K*jM) S Ih M i.mii im. '11h; A met can Ci t> Mav.aHne Ik I ( Ml \(.n \ ( 1111i a Cost a ( i mi ii Iv S.i i cl y ( i ill m iI \V H X. itmii.il S a U t y Council, fur. H n ( A r m s . k m o - l i a Suiety Council U' vj-' u i I t m i l \ . A f i n a (' .tsiull' . *v Sin el \ ( <>. K. A. ( il M i IN, Metals See Imu K i n ni ill I'.. Cm M \ \ , Seat t l e T r a n k X S a k ; > Council ). K O. ' MI MY, I h t h l e h c i n St eel Co. 1.1 u is \ D i l h o i s , Con- i il t ing Kn g i n c cr I w Ik I>h k i i ;, M a - o n City S a f e t y Council C. W . I 'i Mi'i ' Di e Liqui d C a r b o n i c ( h u p . J \ mi il* i )mj a . \ s . T h e i ' h i l a d e l p h i a Gas W o r k s Co. 1hi. I.ot.is !. IHmi.ix. Mel i o j ' o b t a a Li f e I n s u r a n ce Co. (A M. Gownkos, I h., SaU-ty I h v . , S y r n c u - e (. l u m b e r of Co mme r c e W L. I i ci i . s , Publ i t C t d i i i e - Se c t i on I). D bi n Ni i i.. Cou-ulttu' . ; K u e j n e e r * P. L. Im n n i .i i , Ixuit-a- t. ity S a i e t y Counci l D on Mt> A. I; i nki :m m k , T o l e d o S a f e t y C o n n e d D k. 11 \ kr L. I- i sm k, ( J icago Ra p i d 'I ran"it Co. C'u m r i K (.. I'NK, Be r k e l e y T r a i n c Saf et y Coni nii - - i on H o u \ki) Ik l ' oMM, I b u r ou g h - W e l l c o m e X ('<> (l .' .SA.) Inc A m.n w m k Ikwn.i:. Ik , Q u a r r y Section J ohn Ik Gntso.v, W e s t e r n Ll ect r i c Co. H oward I7. G i i m i r r . F.lizabcth S a f e t y Conned O n t o M. G k w i -, Tl i e General Cr uMi c d St o n e Co. W. A. Gi a n - in, A m e r i c a n T e l e p h o n e X Tel ee i ap l ; Co. H \ kkv G p h .iu u*r, T h e P u l l ma n Co I s a i m j ] l \ i . i , T h e Atcbi-oi i , T o p e k a X S a n t a l' e Ry. Co. C. H. 11 \ ivft K. R e f r i g e r a t i o n Se c t i o n 1>. T. 11 u.!;l\' .lov, I k S. Ibirea.u o f Mine S F k \ . \ k }i. I I akui^m.n. h i t ma t i u i i a l l l a r v e H c i * . Ik L. G. I i w w \ u r , Lel .i eb Val iev Sa i et y Co n n e d R. (!. H u i n . C o m n i m c i a l Y t l u G e Sect i on G. T. H i m ml lit, C h i c a g o . X m t h S h o r e X Mi l wa u k e e UK. Co. C i ias. Ik H i m . X e w Y o r k Central Lines H on. I I \ kom) G. H n n m w , G o v e r n o r , State >>i X e w J er s ey I*. C. 11m ii \ . I r . Ai ai i nc Secti on OFFICERS A N D DIRECTORS, Continued l \\ i ki i r f Inin. M.hIi"mi ( Kinil) S .11 t\ C'mua tl S 11 11oi;i<i i t , Pood St. ( Iii ri H C. H dU'nWI, I'uU (T Pies'. St t l mi l f'ui n H H u m , Cement Section M \jr)R N o i n i w A. i \IKII , ( '<Iu n 11Ml - Sa fri \ ( `onta i| R. I) J l . u i l i , Sjriir.;ficM Sa let y ( *oi mci I T hom v, \ K i a K.vs, Ind Mi aI (.'omini v a *<11 o i Olm< Tun s I,. K i i J i >, i 'al cr' on Sa l e l y Council J. M. I\i kim.\.\, I\iiMk_t S f i l i m i \ Y m. C. i\Noi i k, Mi l ua u k i e S a l i i ) ( .omini ->n;ii \ V m S K M.n^i 1)t li nit Iml it''! i ial Sa fi iy ( '(mu il C. L. I.a 1;i>u ntai m., (iiiMt X o i t h e i n Kailua) Co. M m.uakd C*. L u i .i u , (Aulii e d u c a t i o n Section U \ uniy L i a y , J k., KocheMei S a f e l y Council A A u a ' s u s Low, lLo ok Ln Safely Council Titos. I i. M u d >on u.u, C. S I L p a r t s m ni of A.c;t iaihur-: \ \ Ai.rrk Ik Maiulv, Peoria Associati on o f Commerce Safety Council i \ \V. M \'|m)N, Minnesota Sa f e t y Council K. A. McAuui uu, Transit Section M iii.ik Me Ci ix took*, Harvard Uu i ve t ' i t y I. W. Mu! \kti. industrial C l o w s Co. J amis K. Mt: i i k , ( L a n d Rapids S a f e l y Council H \ k o i ! ) 1.. M i.vi.k. L. i. du P o n t de Xc i n o u r s X Co. K. P* Afoia i v, industrial A c t u L n l Prevention A s-mw P ian- kot.i k 1.. M okkiso.v. Street X Hi ghway Traffic Section L kni m' Mi fci'iiv. Alhanv Saf et y Council L .1. O 'Rkd n , J k., Louisville Satetv Cmnuil ( u:or(.i: C. A. O i*p. The iTvtroit Edmon Co. Wu.Tiik S. P \ i \ r , Ac t i u Life X Affiliated G>. Li:w K. P ai.mi.k, T h e l a p n l a M e Idle As s u r a n c e Society of the U. S. H w i n A. P a i i o x , N e w a r k S a f e t y Council Mi s . 0 . M. P n m . v , Kwmstoii S a f e t y Council C i i auus \Y. Pi ndock, S a f e t y P i v . Mi l wa u k e e Association of Com- UK.TCe (.. le. Pt . muoNT, W m r u a n Mu t u a l Liability I nsur ance Co f 11N. L i n k e r Ik Pit I.MUK', L n i t e d S l a t e s '.n-,iiiirr Olisce Ai<Mita< 1'o' Ut.utox, Hudsij u ( . mi nt) S a l e l y C ouncil A lbi kt S. Ri-i.i.'i I ndust r i al Rel at i ons Counsel or s, Inc Li. C ol. I I i.NUV A. R i n i m .j k, l . e hi yh Pot (laud C .nvnl Cm Ih.sTou Robinson', p. asthay S a f e t y Council A. V. kouur oKK, Duluth, Mi s- ahe S: Iron Ratine Us. Cw W' w. i n ; Koslnb\t;\r, W e s t e r n P e m i s \ L a i d a Sa f e K Conned G. L. S antoro, General Elect ri c Co. \ OFFICERS A N D DIRECTORS, Continued Hi . s i n (i. S cii.m i mat, E i i e Sa f e l y Council k \ i ; t . G. S ciioi.h i.r.K, Ra hwa y Salcty Council H akkv A. S ciilt.i /., I ' ni t e d Sl a t e s Steel Cuiji. 11. E. Sixi.v, W o o d P r o d u c t s Secti on E \ ki. S Si!Mn/un. Ctica Safety Council C i v . J ohn 11. Sin.itiUi'uxrt. Ma s s ac h u s e t t s Safety Conned U k. I... A. SumuiY. Be t hl e hem Steel tin. Kkni.'.t I.. Si momiis , New Ha v e n S a f e t y (' ouncil A. E. StNct.MK, Meat Packing, T a m m i " S; L e a t h e r I ndust ri es Section Joi xu. l.t.e. L. S k u .i., Clevehuul Sa f e t y Conne d C. W. S mith. S t a n d a r d Oil Co mp a n y (Ind.) E dwin C. S mith, Pdackstonc Val ley S a f e t y Council W m.tku D cnt S mith, I t el aware Sa f e t y Conne d \V. A. S now, Const r uc t i on Section K. T Sot.i NsTt x. Elliott Servi ce Co. K. C St 'KiNu, l.ansdalc. Pa. (imttr.r, K. S i m i C N s , Sa f e t y Bureau, Buffalo Ch a mb e r of Comme r c e J ohn Sm.wr.u.. ( n e a t e r New Yor k Safety Council A ten it.'it M Tone., Consultin'.; Ma r i n e Knymcer lii.iiRr.i: ( i. Tit w i n . ( d e a l e r Chica tro Sfete- Council. Inc M ajor k. 1>. T rimhi.i , Ri c hmond Safely Council Br i nk If. Yli/t, S u p e r i o r Sa f e t y Council Hu. C. 11. W atson, Ame r i c a n Te l e p h o n e N Te l e g r a p h Co. I I \ hi;v M. Wiiuu.it, Wil met t e, III. I >k. H u m 1C Wr.i'.t.i i n , Ba l t i mor e Sa f e t y Council S. If Wnit i xt; , Liber t y Mut ual I nsurance Co. A W. W iimnt.y, Nat i onal Cons er vat i on Bur e au How m;ii K. WitiTNi.v, W o r c e s t e r Sa f e t y (.'mined T. A. M u s o n , T e x t i l e Section \ \ . 11 M i\ \ ns, Vnion Cat hide N t.'arhon f.orp. E. 11. WtNst.ow, Sa f e t y Div., Ri r mi nj i ham Chaml i er of Co mme r c e \ \ . E. W o i n n . Internati onal H a r v e s t e r Co. K. I. / . w i t , Sa f e t y Bureau, Dul ut h C h a mb e r of Comme r c e ( i. L. / . wick, St. Jo s ep h Sa f e t y Council -7 ,s I I I Tin Pttrp" Tin tli ron i preven jdies t. direci' lation Re. condit diseas' accidrlive it. The [irofit. tion. It ha sentii: o tiu -100 fo- lierslv indi va bers o; tions. ccrns, thc oii th ' ' and < Tin the tii tindei Iron wauk Cone i orpai. mcmb, hersi.:; Tbs .cram nunc devi: make Tb. cxpai. ness o' 'a CO' Industrial Dusts W ED N ESD A Y M ORNING SESSION O c t o b e r 13, 1937 *1 he i nert i ng u;i< culled to o r d e r U\ Chai r man A. S Ur sul a. K \ c c u t i v c Sec r et ar y, lnilu^tnal kel.uioiK Corni^elors, Inc., N r w York City, and Vice-President ior E ngine er ing, National Safety Council, who intro duced the speakers. What Industrial Dusts Are Harmful? Why? By SE N IO R SURGEON R. R. SAYERS Chief, D ivision of Industrial H ygiene, U. S. P ublic Health Service While, d u st s exist e v e r y wh e r e in the a t mosphere, it has been recognized for cen turies that workers in certain dusty occupations arc less healthy than those not so exposed. T he number of persons e x posed in dusty occupations comprises one of the largest industrial groups. The occu pational diseases of workers in dusty at mospheres have been found to he due to entrance m' dust into the system by inhala tion, by ingestion, by direct absorption through the skm, by irritation of the skin, or by a combination of the foregoing. The su-pcnsioiis of paniculate matter in air have been broadly t ermed dusts, fumes, and smokes. Such a classification is neces sarily a i l n u a r i . since tin: line of d e m a r c a tion ii(t(M(ii t hem is not \ e r \ sharp, anil the ei.ii t diliei ( utiation is based on the si/e of the p.ntiile-. linestivations by the P u b lic l ii ai ih Service in dusty industries' i cvcaied that about 70 per cent 01 the dust parlieh.s cNanuned were between I and d iincron- in -i/c, only about 20 tier cent wer e less than 1 m i n o n . and be median size was 1 .1 microns. Indust ri al dust s ar c inaiiilv icss than 10 n u r t o u s m size. Ho we v e r , fibrous du-ts ;n the a n, such as asbestos, ivc been found to eoni.uii particles as l ar ge a< 200-100 mu i ons in the gr eat est diameter. While, gent rally speaking, according to Colli-, d u- ts are mor e injurious as their rlicime.il composit i on (lifters f r om t hat of the human body, or from the elements of which the body is normally composed,1 it is difficult to establish a comprehensive definition for toxic dusts. Sollmann,1 after analysis of various definitions tor poison, felt that it is very difficult to give a definition which will not be ambi guous in some cases, but believed that the following covers most of the points which must be considered in classing a substance as such : "A poison is any substance which, act ing directly through its inherent chemic properties, and by its ordinary action, is capable, of destroying life, or of seriously endangering health, when it is applied to the body, externally, or in moderate doses (to SO Gm. ) internally." Some du-t s are known to be poisonous, while others, in the concentrations ustiaiK encountered, are comparatively harmless, ilowever, it may be stated that breatkinq dust m high concentration is not desirable. Aceotding to Fairhall, the damage arising mini the inhalation of toxic dust may be either local or remote, and depends upon whether the material is a protoplasmic poi-on. whet her it is caustic in reaction, or whether it is absorbed into the blood stream and carried to other centers which are in tm n affected.4 It is now- well established tiiat expo- li r e to certain kinds of dusts, such as those con taining considerable quantities of free silica, has increased the morbidity and mortality rate, f r o m r e s pi r at or y di seas es ; while m e tallic dusts, such as lead and its compounds. 85 t .vi n , v .w.i n . \ i i n ^ t h i l A(// <7 \ L<>//</; I .s.' have been associated with guieinl poisoning/ Dusts may be swallowed with saliva, water, or food, and direct poisoning has been t r ac ed to ab s o r p t i o n by this method; other dusts may act as irritants and produce affections of the skin, irritate m u cous membranes of nose, eyes ami throat, often causing inflammatory diseases of these organs.4 Some inoigntiic dusts arc aide to prnetiate the deep lung tissues and are -ullicu nth insoluble to he retained there. S o me (it these m ay be active in the human ti^siKs, causing definite and p e r ma n e n t in jury. while o t h e r s a r c inert and may be retained for years, apparently without seri ous damage; some are gradually absoibed without causing pathological changes/ All inhaled particles arc soluble, at least to a small extent. It harmless, cell activity is st i mul a t e d 50 t h a t phagocyt es r e m o v e the dust. If the solute is toxic, the viability of the phagocyte is affected and an ineffective a cc umul a t i on results. At the s a m e time, further solute may diffuse into neighboring tissues, setting up an irritation and subse q ue nt fibrosis T h e n a t u r e .as well a s the s ot uhduy of the solute is an i mp or t ant factoi, hut of two substances of approximately equal toxicity, the more soluble form caii'v< the greater damage. However, su b stances of such low solubility as silica may ultunatily produce extensive injury/ Kettle has stated th.it h a r mf ul dusts, if inhaled into the lungs. may activate a latent tuberculous infection; they may exaggerate an active tuberculous lcuon or a coincident infection If sufficient quantities of a F a n n ies.. ihist are inhaled, some o f it remain-; m the limes and causes a mild degree o f iihrnsi\ merely through mechanical iirilation, btil such fibinsjs K nev er suljn h-nl n m!ei ten- uiih the function of the lung ' S o me vviilei , stale dial wlnle the mflu(iiee ol rinnpm-.oiious dii-l- on health is a debatable Mibirel, ahtiniinally high i bal h rale- from brnm hills and pin mmnua are some-turn - altr iimied F> chronie t \ p n on e to n iiiiovie dints. I.mam amount-, of <111 >1 art* tuaasionally found in srippixcdlv 1101 m:d lungs, at autopsy." According to Drinker, there are lour dif ferent types of reaction produced in m an In the inhalation of dust. T h e first and most important are the pneumncotiioseq >ueh as silicosis and ndicstosF, which cau-e specific lung pathology and of t en a r c f ol l owed by pulmonary tuberculosis. .The second type of reaction is caused by toxic dust . like. lead, cadmium, and radium. A third type o f m a l ady fol lows the inhalation o f finely divided metallic fume particles such as /inc oxide, and is known as metal fume fever, 4 hr fourth reaction, allergic in character, is caused by breathing organic dusts such as pollen and certain types of pulverized wood and Ilnur. In all four cases the sob* cau-v o| (lie (lisabilitv map be du-t inhalation, but the iraitioiis from toxie dints n suit l imn swallowing as well a> from inhalation 10 For various reasons it i-> diineult to set up an absolute classification fot dustf fpimnn is rapidlv changing i c g a i d mg tailed inert or hatndess (lust-, and l url hi r investigation niav prove son:r 01 them to hi injurious. So me dusis may have Doth a toxic and an irritant action; while m: the other band, the poisoning resulting from e x posure to a (hist may he the combined e f l o t of more than one mode of entrance into the body. However, the following cl.is 7 Heat o n of dusts, according to physical character istics and physiological effect, is used for com emence. I. Organic Dusts Organic dusts arc tho-e which contain carbon, and were originally supposed p > come from organized substances derived from animal or plant life. Living dustcome under this classification, and are thought to be o f the same order of si/.c ;o industrial dusts, with which they are f r e quently associated. Bacteria arc usually be tween 0.5 and d tntcious, except m a tew cases, such as tin- anthrax baeillii-. which ranges from 1 to 1 micron in bicuddi and 4.5 to 10 mictons 11 length and 10 or 1/ mn ious in di.mntrt Howi vrr, tl is posvj. hie l h a t tin- 1.11; <1 and D - . i v u i v.n n I n - , like the I.ugii ami heavier diisf pailnli-', rifle hie In gi avilv, and do ml irniain -u pended m tin- air. Many llnm-amls <*) on;ame subsf.uicr-, mi lion containing, are made s\nthrlically by chemical processes, sin h a-, dvrstuli-, 1 xplosivc-s, i le. 1. : x n x u n \ ( ; o r c . i x i c h e s ' f s a < the name implies, these at-- comprised of noiiviable particles, which may m may not he inherently toxic or iriitaut, hut winch nevertheless produce untoward cftects in the human organism "Al l ergi c" dn-ts, or thcs< to whieh only certain person are m a m i ml u sin a ! I.iusis become h> persensitive, will] resulting a l l a n a , rltiniiis, or other disturbances, are included in this classification. a. 'I'omc a m l / o r Irritant. T o x i c or irritant dn>ts are all organic (lusts n i n t h produce untoward symptoms, either s y '-tenue or local. Tho s e producing local symptoms arc usually desrrihed as irritant; those produc ing grncial or systemic symptoms arc teimed toxic. A hist may he hnth toxic and irritant. In repo) ted cases of injury nr death f o l lowing inhalation of dust f iom organic c o m pounds, among the chief oltendcrs aie pa ram tram hue, the dimtrohcn/cnr-., chi o r o duut roben/enes, ts in it rophenol, and riit rouaplithaleue. K\o damage due; to intlamma111ii of the cornea has occurred among voikers exposed to methyl violet dust. The tin - 1 trom paraphetn lene di ami ne deri vati ves is particular I> irritating a n d dangerous, cmi'ing not only a Severe form o f dermatitP where the du.-t comes in contact with the 'kin, htu nKo producing acute inflammatmn of ti 10 mucoi h membrane o f * the i expiratory pas-ages.* To x i c dusts may he grinuatrd during the handling o f powdered il\t ' and in preliminary dyeing operations, particularly the hydro-extractor proce-s, where parlicles^arc di'-etninaU d in all d i rections ' Coal' tar and ndigo dyes arc substances most frequently used. Cases of amblyopia have been reported i rom exposure to inhalation of tobacco d t i ' t !: It has liven found that inhaled t o bacco (Hi't exerts a nicotine action on the organism fifteen times greater than that produced by the same quantity of smoked mb.uvo v, i(11 an equal uicotim; content.n N vrrc dermatitis is experienced hv many u <*; k'ers handling pow der containing T.X.T. , c.huh is used in making high exploders. I'iciic acid, which is also used foi tins pmpow. icquitcs (hying, and in this latter stale ha- hrt ii found to produce a dermatitis. I 'i'ih ai id is al-o the oldest s\nllietie or game dyesttifi.u Dermatitis occurs among handlers <> silk with varying trequeurv. S.d.U determined that a rash occmring among workers in a silk factoiy was due to dust irom silk cocoons imported fiom At lira :1 Persons engaged in the maimfai ture of qmmue and quinine preparations suffer from -km phenomena, which occur for the most part un exposed parts o f the body, ami m.r. he caused by ingestion or by quinine dust, o r powder f or m of the pre: ararioi erting a direct irritating ctK ! on the ? Dermatitis due to other xvgctnbe stub as vanilla. powdered a r u m \ tlirmu, etc., have been reported. M Dental lesions, of occupati onal or have been reported among workers in T h e gingivitis caused by sugar dust is 'ified as purely mechanical, wi t h 1; developing caries. Digcstix e di<or( respiratory conditions, and cutaneous ditions fojccially of the face) were found. 17 P o c k workers, t r a ns por t e r s o f gi workers in grain and jlour nnlP. etc exposed to hi -is dur i ng t heir wo r k . P irom cercaP may contain many jnipuri which may cause an i rritating act i on on respiratory passages, as well as in flam tion of the skin. Digestive disturban dental defects, diminution in hearing, conjunctivitis have been observed am millers, a n d have been a t t r i but ed to the eh to which such workers arc exposed/* h. .-lllcnjic. Ma n y appar ent l y innocm substances may produce reactions in p sons of peculiar personal susceptibility, d term "allergy" is used to describe this a dition of by perseuMtivcncs' or ami allergic p he nome na vno^t f r e q u m manifest themselves in skin reactions, lio ever, they may cause acute relictions dwhere in the body. When the rC'pir.go tract is involved we have such well ki 'm diseases as hay fever or asthma, The diseases ma y develop as a result o f hyp* sensitiveness ta such substance-' n< polie from plants, horsehair, rabbit's f ug fm Ieat he r ' , etc. knr installe, iuirieis. w o i ke t ' in ebul-n indtl ' li i f' uli() aie rxpn-rd to unol dm etc., max 'inter l imn bay t r i e r oi a - t h n u It i' unnecessary Ou the otUnding du-l i e.u II Ilie dept Iis oi the lungs gi ant polk r for example air irpoii ed to pinduce theetli-el after being ramdil m the iipp. r re Iii;it<irv p.issagi -'. Should siieli an olid in!:: suhstanec be burly gi ouud it eould reathe alveoli and as a ic'tilt pi ohaldy a physiologie reaction- would he anwler at cl In a survey ut a plant ul i ei e l e - m mixed, ground. and molded, it u.m fourthat M per cent o f the occupational d e n t ' tills there was due to 11>prrseu-itix sly * he xa met h\ 1cue tel i amine and tuim.il del i>r contained in the dint to xxliich the wotke: were exposed a During the fir-t pro C" utfon spinning, cotton-strippers arc i \ cd to d u- t arising f r o m cottun hu-ks a n d r i s >ich produces a typical form of Inna >n]inar> wood dn-t lias been of interc-t r to i t ' purely mechanical action, luit 11 greater care is required in Iian<11iny; tain kinds, especially woods coming ( n u n road. Inr.ui-e of the essential oils itnprcg::m: tluin. winch when freed in the dust \ alt eel ihc health of the workers c o n ned Some of the woods capable of .aim: -kin lesions are Brazil wood, satiniod. teakuood. cutnaru or tonka wood, ck ebony wood. West Indian mahogany, aanfsc in guy a>an, coccolol)a, chestnut wood, vow nod. (. ahi or ni a sequoia, etc. All p e r ns who handle these wood* are not itired, only those particularly susceptible to e substances tliey contain becoming fected." 2. L I l ' I X G O R G . - I X f C D I X T S . T h e s e utaiu particles capable of exhibitir.yi the lenomena of life2 (especially the properly reproduction or multiplication), such a* ctena and fungi. Tliey are usually found tow 'concentrations and arc associated th nnh\ mg dusts in the air. a. /h/c.vWi;. One of the most impoi (ant none: the^e is the anthrax* bacillus, which contahud in the dust from skins, fur<. ool. and animal hail, horns, hoofs, hotu-s. 1'his di-cn-r may occur in two f or ms : t a t . c o u > (in which the organism altects e skin), and pi / i mmar y (when it i> inhaled. - in the form of anthrax known as woolrter-d di-i a-e). r Cases of tetanus, reported in connection :th jute mai mfarturc, were traced to tin* iw materia!, the bacillus having been found . the factory dust.:i Diphtheria, tubercu->is, smallpox, typhoid, o r other bacilhi<. oduecd di-easey iua> result from e xposur e * infected dust-;. Bacterial sensitization can be the cause o f \y of the allergic diseases, namely, asthma, trcnuial. hay fe\ ( v, urticaria, angioneurotic itenia, eczema, or migraine headaches 54 b. FiiHpi. Dusts containing the mycelia ui spores of parasitic fungi give rise to .tmoyance and discomfort. " Maltster's'' itch 'Cin the dust alone has been reported. In rovcncc. reeds used for ceilings are stacked hile still wet and undergo fermentation; :ev become covered with a whin powder a dry fungus of the Mucor famih : Sporo- t ii chum deimatodcs), which is s c a t n u d wh e n llie bar k U stripped olT. T*lii> p o wd e r is i r r i t at i ng to the skm and i n u c o i r im-mbiancs. Mycelia and spores of mould* are commonly found to cause radie*: for in stance, the Mack powder coming from macerated sugarcane stalks. Among husl.rtmakers, the mycelium ;uul spores, in ihe f oi i u of a white mould (hyphottiy a t e ) 11 c111 the rhattun canes used, get shaken out when the canes aie spill, hammered, and cut. causing painful fi-stires to develop on the skin wh e r e they alight.'4 A f o r m of a s t h ma or .spasmodic, cough, s u t u r e d by cotton weavers and known as a-pergillods, has been considered due to in halat ion o f spores of a mildew* whi ch s o m e times occurs on the threads/' In a study of silicosis among miners, made by the Public Health Service, a number of cases ot typical mihary calcification wore en countered. Unstained smear? of those caws examined were positive for fungus, two types of Aspergillus fungi being identified. All of the subjects but one were farmers, teamsters, fecdmill workers, or residents of `onall agr icult ur al t owns wh e r e g r a i n is marketed. Partners are exposed to fungi in t hreshing wheat, haling hay, or handling v a r i ous small grains *' Some other fungus diseases such as actinomyiosis and blastomycosis a ir associated with occupational exposure to du-t. The t o n n e r occur- among wor ker ? handli ng -traw, hay, grass, vegetable dfbri- contami n a t e d with mould, etc. Aotinomy co-)s is likely to affect people engaged itt c ommer ci al handling, storing, and cleansing nf grain ( g r ai n distilleries, llour mills, gr ai n c r u s h ing, breweries, and malting h o m e y etc ) X II. Inorganic Dust? Inorganic compounds arc oi mineral origin, not requiring a living organism to produce them/' A number of dust? not usually classed as toxic may, under some conditions, produce untoward effects on the h um an oi gani sm Classified under inorganic arc toxic and/or irritant, hbm-m-pi enlac ing. and nontihrosis-produeing dusts. a. T o x i c a n d/ or Irritant. T oxic dusts are tho-c which are inherently toxic when in haled, ingested, or otherwise absorbed. Am on g those which produce systemic poi soning, some of which are also irritant, are the dust-' horn heavy metah and their salts, such as lead, mercury, arsem'. . c admi um zinc, etc. 11ritant dust s a i t i nj ur i ous by reason of their strong irritative or corro sive propel ties. As a rule, inhaled irritant substances i m mediately rau-c a reaction in the upper respiratory t i ait of such severity that they are prera tiled fmni reaching the lungs, althoit'di they may cause limy; damage byextension of iiillammatioil if the nmcims im inlu ane is c o n oiled.' I.iine, calcium oxide, and the di-chromates aie examples of irri tant dii-ts. An inoig.iuic dti't may pox-css both toxic and irritant properties, and the poisoning produced may be the combined etlect of mine than one mode o f entrance into the body. Of the directly poisonous dints, the most widely pi evident ar e t hose of cert ai n lead compounds, particularly the oxide, carbon ate and the chromate. T he dust is readily absorbed by the mucous m e m b r an e ; sonic dust passes into the stomach and is dissolved by the gastric juice.'' According to Fairhall, perforated nasal septum is a c ommon occurrence among v, o t k e r s with bi - chr omat e dust s. ' In a study made by the U. S. Publ i c He a l t h Service it was foijnd that continuous daily exposure to concentrations of chromic acid mist " i e a t e r t han 1 mi l l i gr am in 10 cubic meters is likely to cause definite injury to the mis.-d tissues.1' It is believed that a simii.u concent r at i on of the d u s t woul d be equally toxic. In the case of poisoning from some heavy metals, exposure may be to both dust and vapor. For instance, investigations have shown the safe limit of lota! e xposur e to lead oxide dust ami fumes to be less than 1.5 mg. per 10 cubic me t e r s o f air, except t o r pr ol onged e x posur e. 1' In e x p o s u r e to mercury dust and vapor, it was shown that the incidence of chronic mercurialism in creases rapidly with increasing mercury concentration, after such concentration ex ceeds 2.0 mg. per 10 cubic met e r s . 30 Alkalis and metallic oxides are common causes of dei matoses. I .ye, potash and lime are known to cause irritation to plas terers, cement-makers, bricklayers, masons, stonecutters, modellers, and metal platers."1 Ulceration and perforation of the nasal sep tum occur among workers exposed to the dust of soda ash; systemic poisoning also occurs from inhalation of calcium reanmnde d u s t . 31 Cascs of d ernvatitis, scleroderma and can cer are r eported to have been i.'nHed by exposure to dust of arsenic compound-. Cer t ai n a l umi num salts ar c skin hp-itai.'.s and aluminum dipt- may eoutribnt. to the nUt turn of skill and nmcon- iin-mhr me-, through mechanical action.'1 h l'ibro.'iis-l'riuluciKt) Ihi.its. Th e mo t i mport ant of tlie-e arc the inorganic, slight!-, soluble dit-ts which cause fibrous changes in the lung tissues, some of whiii; are seri ous, and some el which cause little or r.o disability.1 So frit" as is known, no inoi gar.-.c substances other than silicon derivatives ctui-e more than a very moderate degree of fibrosis of the lung. Mor eover , there secrr.s to he no evidence that any o t h e r cor,..bluer.', of ordinary- dusts can influence so unfavora bly a pulmonary infection.' Although other dusts, when inhaled in sufficient concentrations over a long period o f time, have bc-cn shown capable o f p r o ducing a pulmonary fibrosis, nevertheless, the pneumoconiosis characterized by nodu lar fibrosis has to date been shown clini cally and experimentally to be associated only with the inhalation of dusts containing free silica. Since this dust, to exert its harmful anion, must enter the finer divisions o f the lung, the particle size of the a t mo- phe: ic d::.-: may hear a definite relationship in tin in j u r i ous effect produced. T h e silica mu - ; : present in the air in put t i des small . imugl. to enter the finer air spaces and of -'.a ' dimensions that the phagocytic cell- m e engulf them. The greater majeuity m pa: tides found upon microscopic exau.matio of the lung fall within the limits o; from 1 to J microns.3' Kxamples o; sihceo'.i- dust arc granite, quartz, sand, pumice, slate, etc In a recent .study among anthracite miners, the correl at i ons between e x p o s u r e to du =(which contained silica) and the ernlencof constitutional changes left little dotin' as to the etiological significance ot the d u : ' in the air breathed. Like corrcdations were found between the silica exposure and tin extent of pul monary c hanges. 13 Wh e n tin inhaled dust consists of silica combine'' with bases, silicates, some degree of dian-gi in the pulmonary tissue may result, in this respect asbestos ilu-t seems to be unique a m o n g silicates ia the prevalence and se verity o f the disease it causes.3' T h e chief distinction between silm.-is tinconditions due to simple reaction- can-' by Ollier dusts is lhe active pndiierati' action in the tissues which results in <>gi c^sivc Modulation. Si l icons, when once .'lahlished, stiongly predisposes the lung" 'o infection, especi al l y with llu: t uber cl e >n:illu". Chr oni c interstitial p ne umoni a , luonic bronchitis, and emphysema are fropicnt complications of advanced devices of ' d ico os 1 he relation o f the acute respiratory in'eetions to the reaction due to diMs other "nan free silica lias never hi.cn established, 'hough a heightened incidence has often e* n s h o wn st at i st i cal l y in wo r k e r s in dn-uy fades It is fairly certain that a du-t d a m med lung, w h a t e v e r t he cause, f a n s mu h ' " r - c it an acute infection do-s u;ervne up* >n il In a study conducted by the S Public Health Service a m o n g mai hl c hui-.her; in er mont , it \eris f o u n d that mai h l e du s t when inhaled in the concentration* h m n d in die exami ned pl ant s pr oduc ed a mild. bi'atcral, linear fibrosis in sonic case", but no erious lung changes were noted and there was no disability d u e to the dii"t, even a f t e r r e a r s of e x p o s u r e . 11* c. A onfibrosis-I'r odifciiuj D u s ts Th e s e re inert, that is. they <lo not cause fibrous `issue to be produced, but may become encapsulated or lie tree in the tissues; or they ate absorbed without production of fibrous `ismic. i ncluded among tl um are 'ihwnhim, coal, m u m d u t n , r n n n . limestone, magnesite, marble, pl a?t u <if p:ic is p' \ p iimb and p o h d i c i 's rouge. Dust Control i uigiru i i ing and i md ic al m u i m l . o r the wo most import ant fact ors in c ombat ing ' 'ic inlust rial duM h a z a r d , and are to a 1o e r ' lent complenu ntaiw . /.m/merrim/ C o n t r o l As ..ui/a1 has tated in a recent paper, "It is a basic principle in dealing with a du-t hazard that die dust should he attacked at its point of origin and thus prevented from being dis seminated into the atmosphere " After the du.-t has been spre ad t hr ou gh o ut the air it is difficult to deal with it, and reliance must be placed on individual protection, which is ever wholly satisfactory. Lanza further cite? various methods used u contr ol l ing dust. T h e s e will he r e vi e we d nit briefly, since a paper dealing with the - abj ect of (ht'.t contr ol in detail, will f ol low -n this pr ogr am. Dust may be entrapped at its source hy suction devices and thus removed and col lected. Familiar examples are exhaust hoods in grinding operations, and the devices used in rock drilling. Generally speaking, the exhaust ventila tion method, where applicable, is to he p r e ferred in controlling a dust hazard. Water may be used to entrap dust and prevent its dispersal, and under certain circumstances it may be of advantage to combine the u- r ol w a t e r and the m e of Miction Someti me' , a dusty process can he completely enclosed in a sealed room or comp.utmvnt. It miM lie remembered, however, that any mec hani cal device of this kind offer aditpi.iic pn.lection only if it is p i o p r r l y <!< i-.ncd. iiisl.dh d, and maintained A gi rat deal of atte ntion has In <u given the Mibjret of individual pruteriu >n 110:11 dust, and there :u e tu.iuv t\p" >1 r . pi . i toty protective device' now available *1 h<, 'e are generally of two t\prs* tln.-e which provide fre-dt air from an ur.conlnmmnird source and those which u l v upon a idtcimg medi um for removing <1u i r m n the an breathed. Where the use of mu h a device: is indicated, only one of the tvprs approved hy die Id. S I h u e a u of Mint** shoul d be used. As a rule, it may he said that m;ek'. respirators, or other mu h pioua tive dexicv. should he Used onlv where exposure to the duM is intcrmittuU and b i n i . 01 wlwtc sonic unusual condition make" a mo i c nd (pi.iic dust control imptartirabh 11 W h e r e bacteria or oilier living duM- in the air a r e associated with a process, Mcfi]i/.ition methods such as incic:i"ed tempcia* tu:e, ulhaviolet radiation, and r f u t u u a l s 1iIco ( ' hl oimc or o t her l uct ci cid.il subM.mce<. m a y he o f l ee. I 'a s t cur i / at i on t e m p e r a t m c ( a b o u t 1 100 F.) will kill most o r g a n i s ms except thoM- bcai i ng sjiores. St e a m d i s i n fection is used for horsehair, and prove? to be practicable if the t emperature does not e xce ed 230 F. Wo o l fibres, however , lose t hei r elasticity by st eam disinfection, and the " I bi cker i ng" process now u<cd in F.ngland includes soaking of the wool in a f o r m aldehyde solution, and drying in a current o f a i r at a t emp e r a t u r e o f 160 T\,: T h e r e are few occupations in which there would be a sufficient concentration of dead bac teria to cause untoward effect? in man. In the case of dusts producing external i r rit ati on, a u x i l i ar y protective me a s u r e s ma> include the use of ' protects r clothing, g l o v e s goggles *111(1 a p r o n s ; as well as p r o tective salves, ointments, or other c o m pounds to delay or diminish the irritant action. General rules for hygiene and good housekeeping .should also he observed. Medical Control. Kqually i mpor t a nt , ami closely interrelated with the engineering phase, U medical control o f occupational hazard*. In addition to directing the proper placement of new workers, and guarding the health of all employees, medical Control js a ch(\!; on the cfiicacy of the engmeei mg control methods already instilnted, o r a mr.i-iiM' of the m-rd for new pr ot ecti ve d e vice'-. It ha h e m stated that " f i u l m l r y has found dial the lust way to treat indusliial mp o i i . and iifnr-.s is to pi r vi i i t l l i u n . " ' 1 and medical u m ln d, through ptcemployt:m nt and periodic physical exami n at i o n s , is on,- of die most i mpor t ant f act ors in Midi pit u nliuii. 1 la- {' reemployment e xami nat i on is made to d let mine the e m p l o y e ' s physical and tm :Ual li l:ies\ for work. It ser ves to di*i h o r die presence of any contagious dis ease i cveals any minor physical defects which might later become serious, o r v. liether the <xaruhire's, condition precl udes his e m ploy n u u t in certain or in all t ypes o f u oi k. It should he remembered that such preemp!o\ incut examinations are not to he made foi dm purpose o f eliminating an employee, lut i.ither for allocating him to the type of wor k for which he is physically* suited. A v.oikvr should he given employment unless totally unfit, or uiiIv-nS his disability, even though shght, would cause him to he a haz ard to himself or his associates. h'u r t h e i lU'ue. the practice of preemploy incut exaimnadons sliould be extended to include (.Ncrudvcs and officials of industrial o r g a n i zation' "The purpose of periodic physical examinations is to secure and maintain physical fitness and thereby lengthen wor k spans."J'- Reexami nat i on of empl oyees s o m e times results in the discovery of defects and disabilities which were not observed at the time of employment. In such cases, an oc cupat i onal adji?stinent should ho made to provide continued employment, but remove the risk of permanent injury. Reexamination of employees is required by law in certain occupations in which the handling of poisonous or otherwise deleteri ous substances may result in the contraction o f disease.11 Since some occupational di eaxes tend to clear up and recur, records previ ous occupations should be iiududed the physical examinations. Thp fu'juri: of examinations should be determined I the medical director, unless other w h o sper lied by law. Those exposed to known oed pational diseme hazards may have week or mon t h l y exami nat ions. 1'' " i t shoul d always be kept in mind that tl basic principle of phy-ical examinations \ i ndust r y i-. to kci p men on the job and r,< allow the physical examination to be mere a v. r e d i n g out process. '"'' References ' Ulunmlu til. J. J .1.I 1> dl A v: . . J U " l! 1 )' ! Ill' ll l i m n II I ( ' o f l ' f i i j o f J t;< h l.O l d p l f - f " I S iml.I.c I I .- m i l Jl.ill. n u N... ' 17. A ;. n l. I' JU 5 Colli-,, I ,1.: ir I.. - I n . I n l u l l Pm u: n. . o, ....... w i 1 11 ri-1 <rt-nce In |)ut P l i U . i ' i s " Mr!i. t . ' s t u r . 1`115. li. M . S . n , l.nu-l.m ' Siiliuinnn. To ra ld . *' A M anu al o f P l i i r r . i f.lm*y " \ V It .S.iun.t.-rs \ Co P/..l.vlc!|.'un. n ; * p.ii r h . d l . I .;n\ r-n'c T " T 'im c 1 >.i I - i: I 'miu.-'.*' Jou rn al of I t i d u - m t l Hw pci io *xn>1 ho col oc:v, N o i r m l i r r, PM Rlooinlirid. J . J. " T h e Sa: ti'din; in. I A::;K of I m l i i ' t n a ! I ) '.i - s " Ant e t i c . m f ' 11>1!c if. a!t!i AC:. i'i on. Vc a r Pool l 935->d t.uM.s. U '. K `' Hi i ' t 11 i r ar d in I ml n - t r \ '' } ; :. Hr.mi . I.t.l. L o u d on. 1*)2 5 A i r 11 \ e io rt e lo: i r '. iPit;ou of Amer i ca. I nc " S c o is a mi Al l i ed Pi- or der . . " M edi ct ! S , , U-, r*:t" ti n Nn. t. Pitt^lniridi. I 'a A n n ! I k PM. H Kelt!.-, K. H. " T h e .Action of i I 'u r:i f. d T) :i- * I n-t. of M i n i n g and M c :a II u r .:y t.mn' or. . la. , . 1 19 ; l. 0 " PiiMC run: a n d Srai'kc * " Oc r u; ' i t 'on . H e a l t h S e r i e s , I n t e r n a t i o n a l I. ibottr (' aha-. I :>nj lrt P t i n k e r , Plinij). " i"`.iii<ni:on of P m umor . v. O''.*' J o u r n a l ni ln.hi-ari.nl ll y.euin- ar:<l l`*.\ col n^v. ( ). tol' or, 11 " I ) \ c i n e . " Occupai on .ami I h. i l i l , S..:n Inti- r n. i i i un. i l La b o u r Ol i n e , l l u m n , *; 0 *- L>-v:v<\ Si r `I iujms. " I n d o - r m l M.il.i-n. O s h u d l 'n: vt-t-ut y Pi Loudon, 19(1 15 P u r - t e m , A. " N i i o t i m - ,\< n o n n u n ! n F: i - Tu!i icon Hit-:." J.'urn d or Jndti-t rial ii\-.;tc:ir. I' Ci-nilu-i. J 0J7 `Winter. R. IVo-ver. " The D m i n i . : .>v- O c c u p a t i o n a l A f n - a u u i - o f ilu- S h i n " If. K Lew. & (.`o. i . t d. , L o n d o n , PM I 15 S e i m ar t ?, L o n - " S l i t i Haz a r d* in Anu- r u I n i ' . u - t r v " t" S. 1'nMi c Hr..ilk P ul ' r . un No 2' 0 '. Pim. -i Ki ?, / (. " I / n h i - f m l / Vr r m. ' o- n- i ' n m e n t a n d Lcttnl A- pr ci >: Kcmch- of Ri-eerii L i t e turc." Journal of Indu-trial Hygiene a T o \ ! c o l n s'v. J ul y, 19 15 !: " O c c u p a t i o n a l Le-noti* in Wo r k e r * in Suira- I l elci niti Le t t e r . J o u r n a l o f A me r i c a n Medi cal A* ci a i i nn. S e n t 10, 1927. .-\/.-t. J o u r n a l of I r d u - t r H i ei cne. I - ei una: v, lO.'X. `' ' H o u r M i l ! ' " O c c u p a t i o n am! ILaM-. - V r Internationa! I r Ol hce. <P-orv.i. {'< >0. IJ M u e r ' , M a v K. " S u - r c p t i h i h l i to !V r c n t : ti- Tint I nduUria! luetn, Alhtny. N V 1 cb 19C vol. Id. no. 2. '> H a n k e r . t' ldlin. a m i H i t c h . T l u n d m o `Tud- t r i al l d i - t " Mc C r a ' c (liil Hook CNn j,i i: . I r New \*.jik. I').'n : ' S c 5 m a i * 7 . l.oti!' . " Skill H i.' li d ia Amo r ; l e d o - t r y P a r t JI " U. S. I 'ui'l.'C lli-iif!i Hull. N . y 2 VK S e p t PMC :: ' T i' imukhi s W o o d * " ("Venp itinii a n d l lr.i S o r t e * . 1n t c r n a t i o t n l l . a h n u r ( k l u c . ' i c n - . wi P'MO y Uo;'r, K W.. \ \ \ . anti StalK-bra-:*. C. " I n d ii'tn il Medicine anil Hygiene." B.nlltcrr, !ti ill an<l Cu\, l.oiubm, 1922 r* Ilr.Mvi, C. T. "Tit- Hi.i^ nO'i s o f B i c t c r i M lirwy." S o tn h rru Mcibc.il Ju tir.il Voi. 2/ , No. Oct. 1921 ' S t e e r s , R. R. a m i M e r e w e f h e f . F . V. **NIi I t a rv n n c D i ' - o s e Due to U n k n o w n Cause. U . S. l 'uBhc Cf.ilfh R r i u r m . 1)cr. 5. I (>J0 . 31 " A i i m o m y r n M i . " O c c u p a t i o n a m i H e a l t h S e r i e s , - i t e m . n i n n a i f..ihotir Of bee , (ctU'V-i, 1920 :r H o lla n d , J. \V. " T r M b o o k of Medical C h e m U r r y at! T o x i c o l o g y . " \V. II. S a u n d e r s C o m p a n y , I 'JuJ.v r lf .h ia , 19.20. niounifsebl, J. J. and B lum , W in. " H e dth H a ? . -d< in C h r e n n i n n I'l. i ti n ^ ." U. S P u b li c H e a l t h 'rvicc R c n rin t No 1215. W ash in g to n , 1 9 )0. Ktisv.dl, Jones, Bloointield. Britten ami Tnom p- m "I.cad f'oisonine m a Storage Battery P lant." '. S. P u b l i c H e a l t h B u ll e ti n No. 2 0 s, J u n e , JO TV k' N ea l. Ju ne-'. Bloom fu b), D a l l a V a ll e a m i K-l- xrds. " A Stu<ly of C h ro m e M rfcu rin h sm in the fitters' Fur Cutting In d u stry " 'aith B u l l e t i n No 2 Vi, M a y , 10 U. S. P u b lic n S a y e r s , R. R. a n d J o n e s , R . ' R . " S i l i c o ' i ' a n d S i m i l a r D u s t P i s e . i ' e s . " Nat i onal S iIicoms C o n f e r nee. W a s h i n g t o n . D. C , Apr i l I i, 1936 11 S . i y e r :, Bl oomf i el d. I) ilia Vall e. J o i n s , D r t r - ' / m , R t u n d a e c a n d lU i U c n " A u d i t . n o 'Viwomn .v -' on r H a r d Coal M u t e r s . *' l \ S. Public lU' .iitb Bu l l i t i n No. 221. D e c e mb e r . 1925. 51 M i d d l e t o n , E I,,. " I n d u s t r i a l Pubv. on. iry D:.- r a s e d u e to the Inhal at i on of D i m ." T h e f.anci t, J 111v l arid 11, 1926. 5' 1>i c r - ' c n , W a l d e m a r 0. " El i ci t of I nha l e d Mnt bl e Dust as Observed in Vermont Marble P i t u s h e r s " C*. S. Publ i c H e a l t h Se r vi c e Kef n u t No. IMO. 35 1,a n z i , A. J. " C o n t i n i a nd p r e s e n t i n o of Sitic ovi s . " S y m p o s i u m ori >.il:co-is (Ail: in-rn.i Tu.l-er- c i d o ' i s As s o c i a t i o n , S a n J - r a t KM'o, 1`127 3,1 N e w r | u i s t . M . N . " M e d i c a l S e r v i r e m I n d o *ry a n d W o r k n i e n 'i C o m p e n - a t i o u I . m - . " \ n f r i . i 'i Csdlege of Surgeons, Chicago, 19)' 3 ; " Medtral Care of H:dm trial W"i V-r t i ona l I n d u s t r i a l Conf-T- m*,* Uni r ' . . Ine. Vo r k , 192G. Na New The Engineer's Part in Eliminating Dust Hazards B y A R T H U R S. J O H N S O N Assistant to Manager, Engineering Departm ent, American Mutual Liability Insurance Co., Boston, Mass. When one realizes that romrol ot the dust azard depends upon the combined cnutri buons of the physician amt the engineer, he apreciales that tlie solution requires scientific reatnient. By scientific treatment I mean the echnie.nl analysis of the hazar d to discover .he c aus es whi ch c o u t u h u t c to i nj ur y o r ill icaith. and the development of control tuelhds whirl) oIily physical l a w ami physiology, .nd whi ch will he di r ect ed at causes t h a t .hint o f most i mme di a t e a n d economi cal reatnient. T h a t goes for handling the (lust hazard in given plant. It gens double for tnquirime .nowlcdgc to the end that the whole problem uiy reach ultimate solution. Right now our .low ledge of the problem is in big chunk s. oosclv put together and largely empirical. T h e r e a r c estimates only to j udge the m.igiltudc of the dust health problem, and it i- m > losely associated with other health problemhat a clean-cut estimate of it alone is inilossihle. W e do know that it is great in the iggreuate, and for the individual plant it may e ver y bot her some and expensive. W h a t actually makes quartz dust cause licosis is not known. It does, so the air readied by workmen must not contain h a r m 'll quantities of respirable quartz dust. I n e x pin-ive methods for making the air cUan are -til! in the r eal m of dr eam. . Much u o r k must he done to know more about silicosis and mor e how to make atmospheres sate tec wtv/y. As an accident prevention job. dust control lies almost entirely within the admin istrative responsibility. The control measures are capital expenditures ot considerable sire A plant with a dust hazard is sick, it needs an expert diagnosis and scientific treatment, which may include expensive major opera tions. H o m e remedies are seldom mud; vot'd, and supervision and employee saicty co:i-ciou-ncss alone cannot accomplish any dime. There may he observed in muntless shopinstallations for exhausting dust wlinh are derisively called "tin knocker" jobs in which the h o r s e p o we r dissipated is out m' ail p r o portion to the air-borne dust moved Ton.uig ellicieucy of material moved may l.c the proper yardstick for pneumatic conveyor- but ii the material to be moved is air. contaminated with nearly weightless particles of dust, the entire health ha z a r d can lie in the hah" of otn per cent of material not moved. I do not mean that unless a dint supri --ion job was engineered it can be no good. There arc many good installations that were never figured at all but grew like Tops'- Tin t'r c t dt mi f r o m ilustincsb wa^. m) i;iti'f act or y t hat d 'l ' iaaicy hold little interest t<> (lie ov.in.-r. Tli i i is exceptional, l n m t v o r , ami I i.tier the opinion that dust supprt'Mon jobs dlMUld Ie engineered. A di!'t-Mippre^Mon installation i*> a safety dev ire. dc-ngm <1 and opera t el to pn >\ idr prolectioii ;i",.im-t possible disease and p i m u l r a sci ec of security which must he absolute. its s.iictv is nut rushing air and rattling chips hut a minimal residua! dust me n. There is tu* 11;<11 i pathetic defeat tor a. du-a e ml p t l job bum to hud faith in its effectiveness .<> low that workers must wear respirators to find tin: rcaMMKihle saiety that was expected from the la ids, (ha ts and fans. Diagnosis and Control ( a t us exami ne some ot the features by wi.aii v.e recognize this (lust hazar d problem, imt\ in.: out the socio-Icgal aspects. in <nder to develop more ini!) the eneiu e i i ' s place in rids du- t control pr ogr am, it -eem- desi rabl e to <t(>aratc as sharpl y ; e we tm!; the diaynostrc consideration-' t r o m t hn- e v.li:c!: di al u i t h control, (ti the first vnmp.o um at we ran place all the analytic al enrnpom. :ts which describe the hazar d and its e \ po-m i . \ he piobubihtv of its pr oducing ill !:e.ddi and all the rest of the medical and m.iiu'tt ;al hygiene facts which make out a c r e avaiust t!;e existing dust, in the `a'niiil eo-.mat ina in place the knowledge of physics and i . e r m g necessary to plan the dust (outroi p m e r a m and so design it that when hotaih d its performance follows prediction that the probability of industrial disease is n di ned p> insignificance. The Industrial Hygienist Our first feature of interest would naturally be the spwith: and relative toxicity of silica, siln a-hearing and other dusts which make up the dust health hazard. Much might be said to advantage about the quality and quantity ot hazard in many dusts. T h e acquiring of this knowledge lias been, and must remain a medical problem. It involves gross and mi c r o scopic pathology and x-rays, and experimental animals. Kngmeers do not talk that language, -'industrial hygienists do; they are a happy combination, half doctor and half engineer. Many of them are quite capable of handling the dust health hazar d in all its phases of investigation and control For the purpose of this discussion I throw' their interest in with the doctors. I want to go bo tar in my- opinion as state that the engineer should not attempt dclme the quality of health hazard in a gi plant or industry, nor should lie* m n b i threshold limits of safe or p e n m w b ! .* du tic-*. ThtA tiuy he debatable, but I shall o tend that the engineer who writes the >pc hiatioiis of hazard and (Just t o h r a m e is rea an industrial hygienist, and is using a \e niiii li broader knowledge than en g i n e m al- me. In die 11r "t Q m tin- quality -if the h 0 hazard A an opinion arrived at alter study:: all the environmental condition-, including t, genera! sanitation, occupational analysis a: a s. ii.utdic analysis of the d mt exposure In die exploration of dust exposures, ti nature of wv.My operations mu-q be view*, i r om physical, chemical and mocha: u*. a-pects, the determinations of dustiness mu he not only counted and classibcd by parn.ci late size-, but chemically and rmncraioeA.dl analyzed. T h e plant layout must be xu; !:e with respect to dust production and distribu (ion. and the housekeeping and existing dm control equipment evaluated. The pre-unce " specific hazards, such a> toxic gases. ub:mr mal temperature and humidity conditions, etc mi p t In: explored tor their Complicating ehc-upon the whole picture. This is di-qim.tb. .v iitdu>tnal hygiene joh, and .some ot the timcntt cal data requires only medical \ i c u p o mt Tin-' is absolute in the ease of tula-nub-study and the qualifying of men for cni;d ment. So far, not one atom of engineering : suppress du>t is invoiced, ft is entirely awr yAs of hazard. T h e diagnosis mu-t be tit* the dtt'tir:e<s is hazardous to health or that is safe. It it is hazardous, it must he brongk down to a speciiivd residue. If it isn't. Dav it alone. On the second point, if the hygieriA: can rmt specify threshold limits gradual-* upward tor relatively less hazardous dust let the engineer not worry about it. Th diagnosis is dust which is harmful and to much of it. T h e remedy is control of the dm* T h e engineer designs controls which \w produce the lowest practical residual dustness. He should rot attempt to write his ou; specifications of threshold limits or permA sihle dustiness. This may be an imj>ort:u goal in the study of dust health ha/nrtK Safe Limits At the present time the medical men a; hygienists believe that quar t / dint is -a; below it\ c million particle*. T h e y hf c m willuig to graduate upward tu 20 million fur medi um silica and 50 million for l ow silica percentages. IT\c million particles is virtually Ut"t tree, and is very diftuull and e xpensi ve to achi eve and maintain. The: decl ar at i on of s a n t y if the installations tun'd r e ma i n in the hands of the medical and lngienc .group* in whose luiuds iiiju lies the responsibility for determining the hazard. \ \ e now enti r the chapter of our discussion intcntled to demons trat e that dtist l on tr ol is an engineering job, that it imi-t he given sceutUu: treatment, not gnes* work, a p p h i n g engineering methods which are bused upon a know ledge ot physical law, the b e h av i o r of dust, the performance of air-moving m ac hi n ery, etc. Prerequisite Knowledge Lvt me recite briefly, a few of the things which, in my opinion, the engineer should know to do this job correctly. He m a n know iunv to make a survey. Surveys depend upon sampling, and sampl i ng i* not a cai ch- ascatch-can proportion. It involves the place, the time, the frcquenc). the amount in u s a m ple. and the number of samples so that m a x i mum. minimum and average data mean some t hing. >o tfiat credibility can be gi ven t h em i ' o r t he tv pc of sampl e i nvolved In* nr.i-t knw iiow to wei gh o r count r espirable dust, as distinguished from large masses ot nonrespirable dtist wliicb complicate the picture. He must know iunv to observe the source* of d u d flood* a* distinguished from condition* of norma! dustiness. He must know the sour ces ijf >liis( and the principles involved in the dispersion of dust. He must determine h o u mini) dii' t enters the problem because j* is part " f the material, and what du^t is ci eat d m tin- p; <ha ss In the 11 a. l u t i n g o f tinmaterial. A iij less survey cannot tell the e ngi neer what bis t ask -t dust control is. T o visualize that task intelligently he should know the ph> sics o f P r o w u i a u moti on, kwvs ni r e - i - t ance to the motion o t pat tick *..oving in aii. hoth when the air is in turbulence ami for stream-line motion. He should know terminal velocities, movement* due to centrifugal mo tion ; flocculatiun and the cffei ts of air motion and the effects of Iiunudilieatum on it. lie must know all about the difficulties of wotting and what is known about overcoming these ddiu ultie*. l ie should know the several e lec trical phenomena which bear upon diM he* liav ior. Tl ui ' c ar e all principles of physic*, which explain the behavior of dust and upon which engineeri ng practice must be bawd. They must be understood and lie taken into account Dust control is not a mat t er ntilv o! gem ral ventilation; the engineer must Mudy the p r o duction as well as the dispersion. Tlu: problem should be aualv/ed to determine the applica bility of segr egat ion, cnclo-m; c, u ut11n :. loeai exliatist and general vcntil.ition. In some instance", substitution of nmi-hazarduiis nuti-ti.il. or non-dust-produemg oper ations ma\ have specific application, and the shoiil! he e.xploicd iirs. This implies 'plant engineering. I am convinced that munv had Misiajlations ar e had because plant eii gnacr nu; was not used. In the designing of exhaust sv'tciiis installed to capture the dml at the point" of generati on. th.e physical behavior ni air moving toward hoods and in duct* mu-: be known, and that knowledge u-cd Ikui. system must consist ot collection hood-. pip ing. air-cleaning plant and a source of mu in Before selecting a hood for a job the engineer must know du- t disper-uou by dviiaimc p r o jection as well as dust dispersion by air c u r rent", and design the' hood accordingly. Knowledge Needed \ he aer o- dvnumi c characteristics of .suction hoods appear to be little known bcrati-w link t hought was given t> them in designing t inmsi nt ls of hoods vvhi* ii can he found t.\ cr> wh e r e in industry. All the possibility for e n t r a p p i n g dust and much of the eflicicmy oi llie svstem lies in this factor. Air velocity, static suction, and rate of air flow arc all related, and they must be* known. It is cs*e:itial to U"L* hi gh velocity of air in certain Iy pc s of exhaust systems to entrap dust projutcd a t hi gh velocities as in the case of a granite surfaci ng machine, and low velocities mt M be Used in others, as in tin* case of cleaning asbestos fibre of dust to present wasting material. Qua nt i t y of a i r and its velocity must he dc UTinmcd, then the piping should be d e si gned to take into account the behavior of air-llow through pipes at low and high veloc ities. W h e r e the problem is complicated b> the large sized particles which go along with the fine dust, how these behave must be taken into account. Pressure losses are very impor tant element- in the design of an c> burnt .s)>K-n'- l-1''" the hoods. loss at the bends, and lu'" in the ducts must not be guessed at. ripe design must take into account the gage (,t the metal and reinforcing to withstand pressures and erosion. The selection of a fan and its motive power is a n u t t e r of calculation, not guess work, powe r consumption in the system is calcula ble. fans follow certain laws, so the engineer must know the behavior of axial /low, p r o peller type, radial flow, paddle wheel and other fan performance. M<tc physics and engineering calculation goi's into the air-cleaning a ppara t us The selection of gravitation, inertial or (titration method depends upon what the th.ist is, the calculation for any method* requires k n owl edge of discharge through stacks, the deter mination of s u e s o settling chamber s ; tile behavior of cyclone-*. 1'he use or non-use of a Inter, and it so, v. hat type, huw it should pit form, how hig it should he. what kind of rc-'i.st.mce and how i n mh each kind offers, to say nothing of their proper location with relation to cleaning, a<u essibdity, etc., ar e all item* for accurate eugiucering determination. Apparat us to <he< k the behavior of installa- v tiiMis must he known and use!; I'crs-nn. cannot be left to guess work. Supply mg s cient air to be exhausted is part of the p: letu. The same may he >aid of heating I>o 1 give the problem too severe a hu up' I think: nut. Remember these two thn. 1. You are dealing with hazardous m. rial >o small in si / e and >o little of it weight that it is as invisible as the air t. hears it. 2. R h y o i a l laws involved in the h:l:..\ of du*t and air rlo not pi m u : i:'.e\p<amet hods of control I am aequamn d w budgets set up for tills pm .hoc which amm to mor e than a quarter of a minion dAM and i k now of many where f/) to SO 11) i: dollars is involved. The need for this much engineering > rogni / cd by mea who know. Already me, has been done toward getting the know'ad min handbook shape. Perhaps the best y of this sort to date is "Fundamentals Kehun to the Design and Operation of KvAm Sys t ems" developed under American Steer .irds Association procedure. The Doctor's Part in Controlling Dust Hoards By A. D. L A Z E N B Y , M.D., F.A.C.S. Chief Surgeon, Maryland Casualty Co., Baltimore, Maryland (..cu-idci able confusion has cxisud in the past as to j u , t what h the physician's fuuctiou m tla* prevent ion of dust diseases, and j m t what \s the engi neer 's. It is very ob\ioi^ upon r u n litsu.d thought that the t wo Mteticvs must wo r k hand in hand in t hen etlot t> to solve the pn>blem. 1lie physician thiuugh his special training must he able to tell the engineer what d u d s are d a n g e r o u s and wh a t ar c nut. Me must know how those dusts cuter the body and the manner in which tiny do their harm, lie must he trained in the examination of p e r sons who are to lie employed to woi k in dust, and to discover those who are already diseased, or are peculiarly susceptible to dust disease. He must he able to ditcct the first signs of disease in workers who arc expost d to dust, and n u M be prepared to r e e o g n i / e the disease w h i n it H lull;, dvcloped. It is not necessarily the physicianA fuui lion to anal yze dust. T h a t is a ta-*k t o r t! c hemi st and the petrograplier. It is not tl ph \ sic inn' s f um tit m to count the pai t iel m o dust in a given industrial atmosphere. Th.r in reality, is the function uf the engineer. 1' is not the physician's function to devi* vent i l at i ng equipment for the removal < dust, nor even to he more than an .ul\i-> as to the means that must he adopted : render the atnmsphei c safe. 'The physician i:evei theless must c o u c h m wi t h his medical knowl e dge and with In .studies of the industrial w o i k r r the >mdu of the engineer. A diagnosis of sihioo*., u example, requires not meiely cliara' ter:-t. occupational history and character Hhc phv - i.d gildings, blit tin* kno wl e d g e .is well lii.it t!u: patient lias been exposed to h a z a r d o u s d l l - ' , in <1:111^t:rr>u-i c o i ucut i at i ous. All dust s xvliai i nhaled in e xce ssi ve q u a n t o i e s may be c o i i s u l e i i d a-, li.irml'ul, Imt only a l ew can J'O r c r a i d c d a , d a n g e r o u s . J lout tlie standpoint of tlieir d a ug cr o ii ' propel tiv>, they may be J i e b b 11 i n t o t hr ee general group.-. 1. i l i n i c whi ch a r e d a n g er o u s bee. him* lit t hei r poi sonous action. Mich a-, h ad, ameiiie, mcrcuiy, and similar -ubslance,. 2. ' l l i o s e u h i c h c aus e only i r r i t a t i on in the respiratory trait, resulting in -neli condi tions as b r o nc hi t i s <ir local ir.i'.aitnncilion; such substances as vegetable fibre, c o r k dust, Hour. March, and o t h e r relative!}' innocuous organic or inorganic materials. 3. T h o s e whi ch t end to pr oduce tibro-hs of the lungs, thereby predisposing to respira tory in lections, especially tuberculosis, such dints as asbestos, siiica dioxide or m a g nesium silicate. I shall confine my r ema rks cliicily to dusts occurring in the latter category. It has been generally believed that the h a r mf u l elTecis o f d u st s inhaled i n t o the lungs depended more upon their physical structure than upon tlieir chemical. It was believed, for example, that silica dioxide, or quartz, was particularly harmful because of its crystalline structure, and the hardness and sharpness of its particles. This concep tion is now known to he faulty. T h e dusts which cause their damage by mechanical in t-ert'en-ncc with function are the dusts which arc relatively innocuous, whose symptoms are transitory, and which subside upon re moval from exposure to the dust. Chemical Effect Is Harmful The disease of particular interest to u, today, silicosis, owes its harmful effects very largely to a harmful chemical reaction oc curring between silica dioxide and the body tissues, h so happens that silira d i ox ide is decidedly a tissue irritant to the body, r e g a r dle s s o f the part o f the body it invades, it causes local irritation, local dcsti notion of tissue, and the replacement of that tissue by scars. Tims, given a dust containing silica d i o x ide in sufficient concentration, in sizes small enough lo penult its entiauee to the ultimate air spaces in the lungs, we have a situation wliiili offers danger to the wi nk e r W e have no ical knowledge as to true figures, hut as a simple rule, we can adopt for practical purposes the thought that the human body can withstand successfully a cmici'iitratioii of dii' t unit.lining IIHI per cent silica dioxide in a particulate size less than 10 microns, in a c o n c n U i a n o n not m excess ot 5.000.000 pai t i d e s per cubic io<>l. If we decrease the perrenl.igc of silica dioxide present in the dust, we can correspondingly increase the concentration with comparative safely. W e must, of cmiise, lake into ac Count the portion of the worker's tune spent in (lie dusty atmosphere. T o arrive at a rough conception of a safe a t mosphe r e, we multiply the per cent age of free silica in a given du-c by the total n u m ber o f particles per ruble foot. If the re-til; is u n d e r 5,000.0^0 the condition may be c o n sidered relatively safe. If the result is over 5,000,000 the condition mu- i [,e r e g a r d e d as unsafe. He ar in mind loo that sthc<>~is is es-entuiUy a disease of great chromcity. except in a l ew exceptional instances it will n r j u i r c from seven to thirty years for a worker to develop advanced silicosis. It is evidnit too that coincident dints may cilia r retard the devel opment of silicosis or li.'i'ten it Recent research seems to indicate that the a d m i x ture of aluminum dust to a sihaous dust will gr eat l y inhibit the reaction ot the l at t er ; w h e r e a s a si 1i cion- du- t combi ned with some al kal i ne coincident dusts may hast en the d e velopment of silicosis. Much research is now under way in p r o b lems such as this. We have never learned how to cure silicosis, hut we are learning rapidly how to prevent it. O u r knowledge in this respect seems to be limited to the removal of dust from the breathing zone of the worker L at er discoveries may show us how to modify existing dusts with contaminant d u s t s t h at will render silica di oxide i n n o c u ous. O w in g to its very great ehrouicity, it ionly the rare case who actually develops disabling silicosis during his iiuhi-tiial l if e time. It is realized, of coiiisc, that e x c e p tional instances take place, hut the coiiividv nt ravages of age usually keep pace with the elTccts o f dust, so that much r' t the d i s ability usually' attributed to silicosis is oiten. in fact, actually attt ihutalde to other dis eases or incapacities which advancing year' bring in their wake. T o me the gic.it peril ot silien-is. the peril not only to the industrial woikcr liimM-lr, hut his family, n i - u m k e r s ;jnti the public generally, is the :weomjuu \ jut; susceptibility to tuberculosis. Complicated by Tuberculosis Silicons per sc dors no! kill. "I nbc/cido-is as a complicating factor cjf silicosis rarely recovem despite treatment, and the indi vidual so afflicted is not only totally d i s abled himself, but a definite menace to all with whom he comes in contact, p.irhctilai ly the U-iluw worker who may have silicosis. So perhaps the most important places in v. kick the scrv ices of the phv sician in a dusty trade arc necessary are --first, along lines ol di-covering and barring from expo-wire to a siliciou** du-t tko-o persons who may a l ready have arrested tuberculosis; and scco;;dIy. discoverinc: those persons already e x posed to du"t, possibly already siheoiic, in whom tuberculous infections may have dcv<_i**ped. It is well recognized that no individual should he exposed to du-t containing silica dioxide until he has undergone a thorough PI.> -it.11 , examination, includin',: carefully made and interpreted x-ray films o f his ch M it is likewise obvious to anyone f a miliar itli silicosis that no person who is cv.(`Dm i| to ulicious dust should lie deni al (he privilege of frequent physical e x a mi n a tion*. and x-ray- of the chest, not entirely to diMvx er the existence of possible silicosis, hut to discover a coincident tuberculosis if such c \ M s A man so di-w-ased should, in protection to him-wlf and to all with who m he conics in conxnt. I>c removed from industry. Let m<: emphn- ue the uselessness o f a plnsical examination, unless it be accompanied by properly taken x-ray films, except in cases ot gross tuberculosis. It iv the function o f the physician, there fore, to conduct in a thorough and an intelli gent manner the pre-employment e x a mi n a tion of all persons who are to he engaged in a du-ty trade. T h e purpose o f this e x amination should he threefold First, to di-wowr ami bar from employment in dust, any pi?-vp who L sulfermg from luherc 111<ini%in an active, a quir-cent or an nru l'<l state A pif-d>'i <\Ci[11<in might be made ut individuals sintering from a so called healed pnrn.iry complex, or a healed ihiMl.ond in ternun. It is well known that expo- ure to s d n a dioxide i- \ e i \ lik K in MUr a u i v i t y a t mb c r e u l n u s 1 o-.n win- b .ma (|im -cent o r a: rest d, and . x*n< h a !< is ri .ufivafc !, the ( h a u t e - <,{ it. very remote. 'Du: srroml pi<ib!'in u !n. Ii confront1111y -i ci an at llic pre-employ ncut phy -ir.d animation i- v.lieiher a " i \ m nuhvidu.! by reason of secondary ph\*aal den moi c susceptible to the ihvclopnuut of co'-i-n than a noimal D he 'iiiteim-^ ti di-easew of die uo-e or upper rc-pir.'.' tract, such Us chrome. sinnsitm, di - i a- e o i lmi':- or air r.-'.'iges or obstruction- u : priiducc moutfi breathing.*' W e must r emember t hat silica dio.\id> not dangerous until it r e a di e s the lung;., , that the nor mal i ndividual retains ni nose ami the upper air pas- ages a la. quantity of the dust i nhaled f r om the atsv. piicre. In ins'.ances where this nasal ret tion is disturi'ed, exposure to silica diux du-t may he dangerous to that indicid' where it would not he to another. It is believed that certain ih-ca-cx of heart and circulation, of the kidm yp> hly syphilis, chronic coincihiit <h**i a-t.** the luu^s, all i r av r ender a man m o t e cepl i hle to silicosis th.an nor mal , A be pbcian at his pre-r inploy merit e xami nat i on i. follow certain t M a l d i d a d critcim in respect, and bar from exposure to dan-geo d u st s t hose p-jrsons wh.o t h r o u g h e x m disease may be mor e r eady j >rcy to sibc* or tuherculo-ih Re-Examination Needed After the applicant for employment successfully parsed his physical cxaminaand is engaged in a dust y t rade, the bo f th.e physician is not yet ended. T h i s wo man mu>t be periodically re-exammed, : to discover the early appearances of p immary iibiosi\ but what is even more portant, to detect the early evidence-complicating tubcrculou< infection A ma n should not he d i . - mb ' e d irm ploy iilent in a dn-tv t r ade m e u ly beran-has evidences <>t m m disabling ' ' iliw W o i k c r s in dusty t iadcs, i -penally sV cutters, moulders, pot tery worker*, si mil ar c r a t t s i i m , ai e Usually highly -kill and it -eems imfoi t uuat e l i n n a -'>e:a! u' ui iui nu miiil of view It) dt :iv t hm pby rm ut **o loi:^ as thev ai e phv n!!> to c a n y <m, <:-spewi.iIfv *uue the actual ahhm: i|ualilu s of siliru-os au- in iluiibi v-M.vth X u t m u a l S a j t i y Cofitjrcss They h| h>uUI be denied employ incut in a dusty trade jI that condition is found at pi e-emplny nicnl examination, hut they should not he haired from continuing an employment m which they arc already cmgaged. ()t C(iur<r. m udi iir ianccs \ on, as engineers, must realize that y m have faded, because if you had kept the breathing zone of the worker tree fioni dangerous dusts, m Iico- w would not he present on physical examination. In this work of pi e \ e nt mg dust diseases in indusliy, it <)ioii)d be evident (hat the closest and must intelligent eouperalion between tlie ph\siei;iu and the engineer is necessary. The ph\Mei.tn iiiihi. throneh Ins knowl edge and research, led the engineer what dusts, or. tor that matter, what other substances used m jndtMry are harmful, l i e mti^l tell liie engineer how 1jc)i dusts or other materials enter the body, how they leave (tie body and what they do in their passages through nr their residence in the hndv. The engim cr n i s i m inn; tell the ph\Mi i;in ot the h.arnu u l / d.U'-ls and other suh-tances vurromaiine !in.w m k c r \ l ie r.m-l make ciienucai and petrographic analyses r: dus(s, and ni.eer tndmated anah-ws oi the atmosphere in the wc>tk-d:op l i e imM mai> mu r\ als, cam[erring with the physician m an eliort to discover whether, in the hunt of their jnmt knowledge, working condition.' arc dangerous. He must develop and install care fully designed ventilating equipment. 11c must arrange for modification of chemical and oilier industrial processes, where such modification is possible, and must bend Ins efforts toward removing 1mm the danger /one of the worker the oh ending substance, u batever it may be. T o o many engineers consitue this function Io o m -Iv . They pass on to the physician as In- responsibility certain functions winch e s sentially are theirs; such functions as clu<t analyses, dust counts, and similar technical duties. All too often it is considered ade quate merely to install a tan Ventilating devices in dusty work mums must be constructed only after careful e n gineering study has given a knowledge ot (he physical properties o f the air and of mhMances polluting it. It is possible to calculate, to a very fine point the vol ume of air that miM be removed horn a given spot t a - m n o v c the dust originating at that place, and the engineer must approach Ins task from ni-U as scientific an angle ns the physi cian apju ouches Ins. * '1 l i n e is no room in industry tor hap- ha/ ai d methods on the part of cither the ph\ vii ;,(n or the engineer. Cement mul Oiwn'V Sct'lions 257 .\ chcchcd and repaired n a i r v i ' , v n me M t n i k m t y ni n m c e d u r r in di- auy supervisory training emirse for any p a r ratiim ihr work- of any man mi any jh; hut ticular industry lies within that industry. We <-lie. a n d WV V. Mi v ! \ c i: in a;ddl| !dll . 1 Mm- A a m an 1ri'in caeh ile_ l u m in ;*1 <",ir - a f e t \ N. rot ; m n - tH''C I'.'cn "o .;\b\ hr\\ c t h e m ;ni meet tiv "V men a d<'cr mt\ u o r k ;uw\ p e n v w\ \ > ;<> \<o. 1 will . unt i l I m i n e r d i l l o uni induct viv-' employ M ic h diliVmit t\|u-s <>i people, under M ich a wide \ a riel y ni en rutiMaiuvs. and place Mich a di\cr'.m'Ui'i' a reiimremeut*' nptiii 1)ui 11 lliat the jirnhlcin ni `iipcrvi'-itry tr,duini; in its mure comprehensive aspects is peculiar lo each type (d indtMry. ] Ih cenerai treatRes on leadership give the ercniudwork. hut the subject matter for must cm "id and see buw c u r job i- heme: supervised now ; analyze the pr ocedure of c \ e r y foreman anri x u p n - v Ru r : m m u n n ; them and select the best; look upon supervision as a process in itself, and see how hest to direct (he work of (he people. It is a lung, tedious, and costly process, hut one which, carried t hrough to completion, wiil pay dividends in the end. .\ meet i n g - v if i ;di t he . c c;u I m a k e vicar : ::e aii- t \ o u IlK'll l l l k' t a - ' i i m o . v' to see that \ o u r r.wn a w ur saf et y ruic< and the m{dcyw'e-\ WV r an aR< n d d u a R who (i>i n.ii ' acni W ED N ESD A Y LU N CH EO N SESSION one hundred per rcn:. O c t o b e r 13, 1937 ill Ili -.fety Work?* icphone Co.. Chicago T he Wednesday Luncheon session of the Cement and (Juarry Sections was a d d u c e d he Ismali Halo, Superintendent of Safety, At chison. T o p e k a and Sant a Ke Railroad, who spoke cm "T h e C o m mo n Sense of S a f e t y / ' T he a ddress was substantially the*) same as another address by Mr. Hale before the Steam Railroad Meeting. T h e complete paper will he found in the St e a m Rai l r oad section ol this volume. difficult problems ;; Cm; rn to the foreman hi> rc- >e safe d'mn; of the pC measures, v.e ha \ e taken i> ie mus t feel t hat the m o - lus resp,uMhdity ami feel W E D N E SD A Y A FTE R N O O N SESSION . to do something about t It there an accident on a O c t o b e r 13, 1937 lered particularly h a /' >Mime that the foreman or fmw to conduct the w<rk Work of the National Silicosis Conference e sure that lie doe' and h a proper t r a . nine pr- By R. C A M P B E L L S T A R R A s s i s t a n t S a f e t y E n g i n e e r , U. S. D e p a r t m e n t of L a b o r , D i v i s i o n o f L a b o r S t a n d a r d s , Miic that a majority M alt W a s h i n g t o n , D. C. - nccident' are dircctly or mie to th fai ture o t >uper.( vel lo innctam proueriy. t timi sui.ervoory training dmg aceueu`o m ncce^sary. Silicons is strictly an occupational disease. .Medical H-irii' c ha- not t cpi Tied '-lira d i d as aliening any indit duals except those who, over tvlalivciy long pci oils of liinc, have u o r k ed in an ainm-pliri c where the air the Department. This act, anione, other things, gives the Department of Labor the duly "to foster, promote, and develop the welfare of the wage earners of the I'nitcd States, to improve their working conditions, ut of a mi;h r \ )'Ory training ' more dilucidi nrocedure which they breathe contained excessive con cent rat i ons of j ret: silica. and to advance their opportunities tor profit able cniploynu'iil." ut of a tcchmcal <r \ oca- T h e i nterest of the U. S. De p ar t men t of With this in mimi, and believing that > urse. Apart troni th tcch- Labor in a b r oa d social and economic pioh- t hrough joint effort of all concerned, nitidi I ivcd. th.ere d"es w t ceri .1 iormuia. There i<. of Icm such as this lias its origin ni the ( hg n n i c Act, effective Ma r c h I, 1913, which cr eated could be done to eliminate the hazar d, the Secretary of Labor called together in Wasli- nylon oil l-k.ljiu.UN 2(>. 193<> a y u m p *>l about 75 iiu'ii representin'.,' leader- in iiidtis(nc- haviny a silica pmhlem. labor Ifinlrr", and o u t 'l an d my representatives of (Ik* nikdical, leya!, and c ny me ei i ny p r o i c ' s i o n -. as well a> insurance c ar r i er s a n d Sl at e a d m i n i s trators. Al t e r enusidertuy c at i ons plm-us o f the silicosis problem. 111i^ y i o u p generally agreed that through a pool i ng o f knowl edge and a frank discussion through the conference method impoitaut a d v a n v - could he made toward. hrM, o \ c r e o mi i i y the It\ - t c n o a l at titude on tlie part o f employers labor, and i!|1k'i >; second, a l t er can. ti d inv e-tmai i on. to consolidate in o n e place all known data with regard to the preventive o n y i m e n n y methods; third, analysis and r e c o mme n d a tions in connection vvidi adequate standards of compensation for those uoikci's di-uhkd as a result ot the disease. As an ou ly ro uth ot this initial mertuey, a n o t h e r yr<>up, si mi l ar in composi t i on t o the hrst cniiterence. hut expanded to include some 200 individuals, was invited to come to \ \ a si; in" ton on A pi 11 Id. 193(> to on l hue way s and means of attacking the prohlim After hearmy silicosis discussed from the stand point ot the employer, labor, and the inedival prot es si un. ()> o n t ' t a n d m e exper t s in the held, tins large group endorsed the c o n f e r ence method as proposed, and as a result lo ur main working committees were a p pointed by the S e c r e t a r y of La b o r with t he advice and consent of the group to mvestiyaie ami report upon the outstanding phases (jf the silicosis problem. These committeewere: (1) Committee on the Prevention of Silicosis through Medical Control, (2) Committee on the Prevention o f Silicosis through Engineering Control, (3) Commitlee on the Kcononiie, Legal anti Insurance Phases of the Silicosis Problem, ( I) Commitlee on the k c g u l a h n v ami Administrative Phases of the Silicosis Problem. A fifth committee, known as the Correlat ing Commitlee, was named. It was under the chai rmanshi p of W, H. Camer on, Ma na gi ng Director of the National Safety Council, and consisted oi the chairman of the four tech nical committees just mentioned and iwo ad- \ Lot's, one oti lalxn prohU m- .md *iiv on mining matters T h o u commi tt ee m e n i b u s -wived without compensation and yav e freely of their time and effort in study iny the problem from their respective viewpoints. After nine mouths of careful and searching study, these commit tees advised the Secretaiy of Labor that they were ready to report. Consequently, on F e b r u a r y 3. 1037 the Second Nat i onal Silicosis Conference was called in W a s h i n g ton. At this time summary committee r e ports were presented to the Secretary and Considerable discussion was given them. Shortly al ter this -econd natinnai c o nf e r ence the Department published, as Pullet in No 13 of the Division ol Labor Standard-, the summary reports o f the four coimmltevs reterred to above, together with an a b- i nut version containing the principal (indinys and recommendations written in imn-technical kinyuaye. d'he full r e p o r t s of die committees, c o m pr i si ng several llioii'aiul typewrit t en page*-, ar e now being edited and will yo t<j flupr i nt e r very shortly. It is e x p e i u d that they will be issued in four separate volumes sometime cluriuy die fall or early uniter. Nature and Extent of Silicosis Physicians yenerally agree that siheo-is, in the l a y m a n 's l auyi uye. is a di-ease of the lung*, c at te d by hreathiny air containing silica dust, in which the normal lung tissue is replaced by fibrous or sear tissue. Silica dust is Umtul in many industrial operation*;, but the ha za r d is acute only in Mich i ndust r ies as metal mini ng; anthr aci t e minitty; quarrying. drilling, and tunneling in granite, yauister. and sandstone; smelting and reliniuy; foundries; potteries; ylass works; stone-products industries; grinding; hutting; and samlblastiuy. Oi the *19,00(1.0(10 w i n k e r s in die I 'nited St ales, only 1,0011,1)00. or 2 per cent, it is es t i mat ed, a r e in any way exposed to the haza id of silicusjs. About halt ol this number, o r l per cent o f dm total n u mb e r of woiker** in die country, are exposed to a seiious haz ard, a nd a ppr oxi mat e l y 110,000 ol thc-e h.iv t silicosis m some deyree. Medual examina tion *d 1 men act ual l y at wor k indicates that between 3,000 and 5.000 workers are serioiish affected by tbe disease, in addition to those ahead) permanently detached from their employment by reason of disabling sili cosis. 'Die stain** of the 1,000,000 w o r k e r s e x posed to the hazard ot silicosis was analy/cd thus by tin* conunit t ees maki ng the s ur ve y: A percentage ot the -1,000 to 5,000 workers ba\ini; sjbcusj-, are completely or partially disabled because of tins disease and have their dill'u tilties f u r t h e r c o m plicated with tuhei culosis Tlie remainder o f the -1,000 to 5,000 have silicusis and disability in some degree, but no tuberculosis. Ap p r o x i mat el y 105,000 have silicosis, but no disability and no tuberculosis. Approximately 000,000 are exposed to silica dti-q, hut have tint contracted the di s ease. 0`niUrai y to popul ar In lief, silicosis is slow to develop. (.Anally it takes seven y ear s or nun c oi e xposur e 0* m Ih a d u - t l or a wo r k e r to contract the di<r:isr A few cases that have been known to divelop m as shnit a period as one and one-hall year's occurred undr-i cvlrum* and t mt u i a! c o n d i t i o n s : ' O n the other hand, many workers have labored under ordinary exposures to silica lor more t han M) year s without d e mo n s t r a t i n g any trouble whatever that could be diagnosed as Silicons. Silicosis Prevention Silicosis can be prevented in three general ways: First, by preventing the creation of silica d u s t ; second, by pr event ing the d i s persion of dust into tin: a t mo s p h e r e of a working urea; and third, if it A impossible to apply the first two met hods, by the use of personal protective cijuipiueut such as respirators, to prevent the inhalation of the dust. In carrying out a prevention program, many agencies must cooperate. In the view of the committees studying the problem, the employer is called on to do most of the work and to spend most of the money. Hut his wo r k and money will ne v er accompl i sh the m ax i mu m results unless the wor ke r is will ing to cooperate and carry his share of the responsibility for helping to control dust and f or Using the personal prot ecti ve e qui p ment. In addition, physicians can play a definite part in preventing Silicosis, as can aDo en gineers, insurance companies, legislators, ad ministrator>, and others. 4 T he reports of the conference (<nnmtto on engi neer i ng control and medical Cotitn r ecomme nd specific procedures for attack mg the problem through thu>c two avemu of pieveution. A partial list of these recoin meiulalions follow s : Survey the working conditions to deter nunc the severity of the hazard and itub cate w h a t needs to be done to decrease i: Secure information on best procedure. Design plant for dust control. Provide building ventilation St or e dusty materials in duqt ie ht bins. KuelosC material-handling equipment. I-olate dusty precedes. Provide wet methods of operation -- Wa t er , oil, and o t her liquids may be U"ed effeeti vely-- 1. T o supprgs> dust at the point o f o n x u in such operations as rock-drilling; ban dhrig, pulverizing, and milling rock and m e ; gr inding metal on gnndstuiii-s : ahraMve-vv bee! cutt ing of gr anit e and s a n d stone. 2. T o pr event the rcdi-pcrMon oi du-l t hat has settled mi the Moors, wall-*, and oilier s u r f a c e s such Us in the gr anit e i n dustry and in foundries. Pe-igii equipment to control dust Kstablish good maintenance and house keeping procedure. Provide respirators. instruct the workers. Responsibility of Workers T h e cooperation of the workers is neces sar y if the ha z a r d of silicosis i-, to be r e duced to the minimum. The uoiher should realize that the safe practices recommended and the equipment provided are designed to prevent injury to himself and to his fellow empl oyees. T h e equipment shoul d be um.mI as di rected and e very effort should he made to maintain it in good working order. F u r t h e r more, the wo r ke r is frequently in a p o si tion to o bse r ve faulty equipment arid unsafe practices, a n d he should make it a point to report all such conditions to his supervisor Statutory Regulation While the primaiy approach to the proh Icm must be the prevention and diminution 2 no / t \ v / / / v - s i x t h Vt i l i ot t al S a j i ' l y C<>mi tss ol the hazaid, the f a d must lie recognized that until si}ic()s jv }as been wiped out, vvoikcrs who now have the disease, well as t hose wlio may conl i act it, must u v e i v e workmen's uiiiiprucatmn just as do those u o i k c r s who abe injured in accidents. Aerm dmglv, the committees ni the silico sis conference were unanimous in presenting the following recommendations: ('overage for silieosjs in the compensa tion acts of all Slates This coverage should he compulsory. Because of competition between the same or similar industries in various Stales, the laws, rules, and regulations of the several States should he as uni form as practicable. Should Be Insured T he employer should insure his obliga tion for compensation either through selfinsurance subject to the posting of ade quate funds, or with an authorized in surance institution. i nsurance should not he domed any e m ployer, provided the State authorities certi fy that he complies with the State require ments as to proper safe working condi tions. and pa> s the p r e mi u ms involved. Workers having acti\e pulmonary tuber culosis and vilicoMs shoul d he removed from employment. Such workers should he gr a nt e d suitable compensat i on payment s and medical i are. Worker*' disabled io m silicosis (hut with no tuberculosis) should ultimate!) he gianlcd the sanie amount of compensa tion as those disabled l\ accidental injm v I wo )v.o's is a reasonable minimum limitation petnul for tiling chums subse quent In the date ol the last CAposuie. Further Activities of the Department of Labor In e a r n i n g out its dut y as staled in (lie haste law, the Ip. S. D e p a r t me n t o f Labm has conceived that there is immediate need for the c onver si on of kn o wn fact, in the medical and engineering helps working toward prevention, ami m the legal, m-nrancc and reguhuore phases looking toward ade quate w o r k m e n 's compensati on, into a p r a c tical, readily u n d e r st ood p r o g r a m winch will adequately take care of the silicosis prob lem. in its program of cooperation with the IK Slates, the De par t ment of L a b o r has in cluded a section covering silicosis and simi lar dust diseases. This breaks down into three main sub-headings: (1) Assistance in the preparation of reasonable and adequate codes, rules, and regulations prescribing methods of prevention; (2) assistance in the establishment of equitable standards of w o r k m e n 's compensat i on f or (hose e m ployees disabled as a result of the disease; (3) a general educational program among St ate officials, fact ory inspectors, etc. so that t hey will be equipped wi t h a dequat e knowledge concerning the disease, its method of prevention, and its proper treat ment u n d e r the wo r k me n ' s c ompensat i on law*. Follows Two Lines This application program, which is just nme getting under way has been commenced along two principal lines; (I) The compiling of practical information concerning actual diM control installations in typical silica hazardous plants, together with approxima tions as to coM, not only of installation, hut ;ikn of maintenance of dust control equip ment m such plants; (2) a p i o g r a m of visual education supplementing the Miivmary and lull commi t t ee rcpoit- of the Nat ional Sd>cumn ( ' oni r r eucc. It is c ont empl at ed that in this held such medi a a** him strips, l antern slides, posters, ilhi st i at ed bulletins. etc wilt he utilized. Fur t he r , in t onnect i on wi t h the various exhibits of the d epart ment , show n at various large expositions, trade association meetings, labor a n d technical oi gam/ . at 'mu meeting-, etc., il is contemplated that much factual l uf oi ma t i on will be used, pointing tow a i d wavs and means of c o n c c l m g the hazard and of establishing adequate stand ar ds oi w o r k m e n 's compensati on. Following the address he Mr. Starr a round table discussinn of outstanding hazards in quarry operation took place. This concluded the Wednesday progi am. Slearn Railroad Meeting :i I 3 ;.i t I< I W ED N ESD A Y A FTER N O O N SESSION O c t o b e r 13, 1937 I lie 'OMoit u.iv (ailed lo oi dei I*\ \V. \V. Wo o d , b a l l i me n e and ( d u o Ka d i o ad , 13;dti- niotc, Md.. \slu> presided, iul i odueiitg; (lie speakers and directing; the discussion. The Past, Present and Future of Railroad Safety B y J. M. SY M E S Vice President, Operations and Maintenance Department, Association of American Railroads, W ashington, D. C. No industry in the world requires more dn ersilied study and more exacting applica tion of saf et y principles t han the st eam rat 1road industry. Picture a qua r te r of a million miles of r a i h oa d lute color ing in a virtual network the \ast expanse, of the United Stales. Over this network arc operated a hilhnii t ia m miles annually. Vast car d and termi nal oper at i ons a r e necessary to make, up liie beginning of tin: j o u r n e y oi passenger s and goods, and to hi oak up at the cm! of that niinicv the 12 imilton t r a ms that accumul at e that hilhou miles T h e s e t r a m s c ar r y 500 million passengers and one hdhnu tons oi h e i g ht anmiallv. It requires m o i c than one million lailroad cinplovecs to ; im the tiams. make them made for road movement, su pervise and saicguard their movement and mai nt ai n the equipment ami lo.idlied, as well ts pci m i n t the n u n v i.lher d u l i e s im denial to flu- pi oduet i nn (if l a i h n a d ti aiispoi taliou. 5a tet\ has m the past, is todai, and alwavs will he the l ust pitmupl e m r ail road opci alions. But it is u i t h i n the past fifteen r e a r s that g> cutest advances have heen made m raihoad safety. During that period u c have seen a complete remodeling and modernualii'ii of railroad physical properties. Koadheils l i me heen s t r e ngt he ned; bridges, trestles and culverts rebuilt; tracks have heen laid with heavier rail and with treated lies of greater service life and de pendability; grades and t u n e s have been eliminated or reduced; signal systems have been nuxlorm/cd and extended; other safety devices have heen installed; new and more powerful locomotives, embracing all modern safety dec ices, have been pur chas e d; new ears, both freight and passenger, have been installed. This capital improvement program has cost the railroads about eight billion dol lars since 1V2.1. and a large part, if not all, of that huge sqm had a henelieial effect, di rectly or indirectly, on the safety of operat urns. But the engineer's job D m , i r done. As s o o n as new equipment, nee- mil, or o t her devices arc installed the engineers go to u o i k to develop more etticieiit and safer units. 'I'he railroads spend milfoils ot dollars anuuulU m leseaivli and laboratory work experimenting with enginre: mg impiovenieut' In all tins w m k safely of p n m a i y importance An invention which might mean great economies to the railioads would not liiul n s way to a single locomotive or car if its use m any wav lessened the o p por t uni t y for safe opcialiou. Conversed, any improve ment, mecliame.il o r otherwise, pr omot i ng safety of operation ininiedi.ttcly commends itself to railroad officers and employees. T he scarcli f or g r e at er safet y v. ill cont i nue so long as railroad transportation is used. About a quarter of a century ago, the 387 d1 n f l Il,i t. - t r nerr 4k S i r u m !\ till m a i l M r r / i i n / .30.3 1 THU RSDA Y A FTE R N O O N SESSION O c t o b e r 14, 1937 Safety, An Executive Operating Problem B y R. C. W H I T E Assistant General Manager, Missouri Pacific R. R., St. Louis, Mo. Safety is an obligation of management. followed' hy a thor ough analysis to find the Without the constructive leadership and day- direct and underlying causes and the pro to-day urge from the executive and operat cedure necessary to prevent a recurrence. ing heads, the movement would lapse into a perfuntory activity. P r o o f of its sincerity will d e p en d p r i mar i l y on wh e t h e r m a n a g e me n t will ma k e T h e safety moveme nt is recognized hy the first essential move m the p r o g r a m -- execut i ve and o p e r at i n g olliccrs as a medi um t hat is, aut hor i ze the e x p en d i t u r e of mo n e y for building up and maintaining that rela necessary to make the maintenance and op tionship, that fellowship, which broadens our erating plant a safe place to work. views, enriches character, and brings the Golden Rule into practical application. Management recognizes that our economic Safety and Efficiency system must enable men to live on an. in creasingly high plane. It must enable them to fulfill their desires ami satisfy their r e a sonable wants, ana-give lliem that feeling of sicurity which is essential to happiness ami cliiricney. Having made the derision that safety is an executive problem and responsibility-- that accidents must stop-- it is then essential that Analysis of the underlying causes of in dustrial accidents and preventive measures to he applied has made Lincicasingly appar ent that those factors which aic producing accidents tire very largely the same factors which tend to lower the quantity and quality of product ion. Expr es sed in another way, safety and efficiency are as inseparable as t hough one vvord. l ~ o e r - J ",r a t c i a:.-s *V' gcrfc -tA * xn 'jrxr-. rx d a s z a ^ ' . t c.-j-t . *a a trag. '.'> -a5c.?v'- ~ : s : d s f i c d a res i;i f it tT X . YcVZ TT/Jil r x career management promulgate, and follow t hr ough, a plan that will drfmilely fix this decision in the minds ol all the individuals who collectively omipiise the industry. The follow t hr ough mu-l he such that di pat tiueiil heads, superintendents, ami every nniiibci of the super vi sor y force will appreciate the need for a constant, active interest in safely; will u n d e r s t a n d that passive interest will no inoie produce results than would llie same interest in production. Supervisors must be made to feci that the prevention of accidents d e ma n d s the same tv pc of he ads - up s u p e r vision that is given to the oilier problems affecting cost and service. In coupling safety with efficiency 1 have not minimized it ns an executive problem, hut have cndeavoicd to indicate that its solu tion is an executive responsibility, both to his individual industry and to the employees that make it a going concern. Rail transportation is a scientific business in which laboratory research, expert engi neering, trained builders, and skilled workers share a part. One of the mam factors is a group of employees who are loyal--who appreciate that their railroad must give the kind of service that will st i mul at e and accel erat e the 2 gaavg-urdy J 23C JJ r v l d. itc* iar repeated nasal s ir_ >i:d : ..tc r a c e s A5> axt e Kk--e old per arsd L>mg T h e executive must find a way to indicate di rectly that it is the responsibility of the. department heads to carry out management's program, that authority is placed in each superintendent's hands to put accident pre vention on the same basis as production. A complete .factual and descriptive report development of the territory traversed. The successful solution of our problem de mands the type of aggressive individualism in execut i ve l eader ship that will at t r act a nd command loyal, collective , cooperative effort on the part of all who produce rail trans por tation. of cadi accident must he made. This must be Ou r major concern is leadership--leadv: -