Document KGp7NXBeR5Gpam4qERmVvaE06

Disease THURSDAY MORNING SESSION October 19,1939 The session planned for the discussion f problems' in industrial occupational isease control was called to order by u S. Johnson, Assiiunt to the Manager, Engineering Department, American Muual* Liability Insurance Company, Bos on, Mass.,, who presided. The problems rere presented as a panel discussion, and Chairman Johnson introduced the memtersof the panel, as follows: Roy S. Bonsib, Chief Safety Inspector, Standard Oil Company of New Jersey, few York City. Warren A. Cook, Division of Industrial Hygiene and Engineering Research, Surleh, General Accident & Liability Intnrance Company, Chicago. Dr. A. G. Crunch, Industrial Toxicology Department, Union - Carbide Company, Mew York City. T "\ Leonard Greehborg, Executive Di re /, Division of Industrial Hygiene.' Mew York State Department of Labor, New York City. ; Willis G. Hazird, Personnel Division, Owens-Illinois GUssCompany, Toledo, O. Dr. E. G. Meiter, Director, Industrial Hygiene Laboratory, Employers Mutual Liability Insurance Company, Wausau. Wis. Dr. O. A. Sander, Milwaukee, Wis. The Discussion Plan CHAIRMAN JOHNSON: We have agreed to have a working base from which we will. talk. This working base from which we will try to develop our opinions is what I choose to. call a triangle.of responsibilty, visualizing what may be called the three A. B. C.'s of an equilateral tri angle. At the top of this triangle is manage ment of an industrial enterprise, the man who has to pay the bills, the man who hires the labor, the man who worries about their health. On the left base is the medi cal side. They are the group employed to carry, out the medical part of industrial management's responsibility. And on the lower right is the third base of this tri angle where we find the engineers or in dustrial hygienists, who have to develop and prepare for the operating group the controls of occupational disease; as far as engineering is concerned- with :-coutrolling them. "! . Now, there is a strong tie between the medical and the engineering phases through that base line of, the triangle. What we hope to do in discussing each topic is to develop that tie, which we will1 call the balance of opinion between the. medical phases developed by the doctors on my left, and the engineering phases de veloped by the engineers on .my right.. I would like to ask this panel a ques tion. For a great many years occupational hazards have been studied in rone indus try or another. Would this panel feel, let us say, sanguine that any industrial enter prise is now ready, by employing proper personnel, by searching out the answers wherever they may be found, to solve an occupational disease problem if they have one, and by the proper solution maintain the safety and health of .the employees? Put another way, are we still groping in the dark on some of these hazards by reason of conflict of opinion, conflict of experimental data and theoretical expres sion by folks who find the, theoretical haz ard in exposure -because it is suggested in the book? Will Dr. E. G. Cranch talk briefly along this .line of suggestion? DR. CRANCH: This question is a broad one: Is' any industty satisfied that it is in a position to solve an occupational disease on the basis of present informa tion? I would: say, absolutely yes, for; the majority of occupational disease problems are sufficiently understood to adopt effi cient measures for control. 133 L# \ PLAINTIFF'S PLAINTIFF'S EXHIBIT EXHIBIT p W'0156?3 |g 10 134 28th National Safety Congress CHAIRMAN JOHNSON: Frequently arsenic and benzoL The - chief, reason, it measurer I hear it said, "Well, why should I do seems to me,* why we still continue to i tion. Or anything about this until you folks come have poisonings in industry is because the question to terms on whether I ought to have two employer and the worker do not realize technical! parts per million or two thousand parts tire gravity of these hazards and do not - men . tea per million?" Let us develop this farther take the problem seriously enough to in proper in and ask the opinion of Dr. E. G. Meiter, stitute the necessary and proper means of on the engineering side. prevention. MR. 1 trouble ! DR. MEITER: I agree with Dr. CHAIRMAN JOHNSON: Now I am Cranch that there is enough known to going to switch, to the engineering side has been ing with solve these occupational disease hazards. If sojme employers are .not willing to do anything at all until all possible informa tion is available, I would say that they and;ask the same question. Let us visual ize an industrial enterprise that is fearful, that has a notion that some exposure is a serious one, and wants to know if there new snbi stances i pretty h thing, as are never going to start. ' In solving these, occupational disease problems, we have a progressive solution. In the same way that die 1940 automobile could not have been built in 1920, just so are we progressing in all the brandies of engineering, ventilation, ventilation equip ment, and respiratory protective devices, and so I think adequate information is available. A Basis for Truth is anything from an industrial engineering standpoint that will make, it impossible, or diffietdt to devise the proper instruments to measure the quantity of exposure, whether it be dust, gas or fume. I am going to turn that over to Warren Cook. . M?. COOK: Today we have more methods available for - finding ;out how much of the injurious materials a man is being exposed to than we Vhave ever had in the past Formerly it was a very labori wants tc you can evidence formatia When . can on!; means a give. th< they car which ; measure CHA! - CHAIRMAN JOHNSON: I think we have a balance of opinion there. If you . have an occupational disease hazard, there ous procedure in most cases to analyze the atmosphere inhaled by the worker. Today in connection with more and more , is enough knowledge stored somewhere in the books and brains to tackle it or solve it in. progressive fashion. But we are duttered up, I think, by a lot of crack-brained notions.-?.I have read any quantity of; liter of the injurious materials, we are having placed in our hands and are having de veloped methods which will quickly tell . us howv-lnuclKof the injurious material is in the atmosphere breathed by the worker. ature ip/which somebody has ventured the We mm devices which will determine assured problem . agreemc pational coped y deuce t< are inst kind foi that the opinion that because such and such ma the ebneehtrafibn. of carbon monoxide Let t terials are used, we must have a hazard merely- by reading a gauge. Similar equip that-is just about ready to kill off the ment is being developed for other injuri population of the plant.' ous materials. For vapors, about the best Do we know enough about the hazards and control of benzol, silicosis, arsenic, device is the Innerperometer, and we hope we will be able to get equipment of this land manufactured in this, country one of phosphorus, indium, x-ray, and so forth,; these, days," but at the present time it is to sort out the truth and build upon solid fact an effective, safety program? Will Dr. Leonard Greenburg develop that for a couple of minutes? rather difficult to obtain.. . Practically all of the injurious materials in industrial atmospheres can be.-deter- mined. Some of the methods are more ease cot Ike mi my haz 'I am si - am set . hygieni -'a progi ment a whatev there w reason' DR. GREENBURG:. It seems to me simple than others, but methods are being that there is a definite'body of evidence simplified all of the time so the safety en which is available on the more important gineer in the plant can avail : himself of Let occupational prisons' and for the more these methods. that pr important occupational diseases, that makes it possible to prevent and control these poisonings and these hazards with a great deal of certainty. ; CHAIRMAN JOHNSON: Now l am going to ask . Roy Bonsib a rather critical question. In cases of-doubt, where fear has to be balanced with knowledge, would consist DR. -sized tl occupa That holds for substances such as car , he think it advisable to attempt to define along bon monoxide and lead and chromium and a hazard in a plant without technical initial Occupational Disease Control 135 n: jurement? That is, by visual observa to a particular occupational ..hazardis as tion. Or does he -feel that it is beyond all necessary as is the exact, determination of question desirable to have the survey made! a hazard by engineering medtoda technically by industrial hygienists or by men trained; to sample properly with proper instruments?: .- , MR. BONSIB: I think the greatest trouble in industry today is that there has'been too much guess work. In deal* ing with insidious problems such as the new substances and some of the old sub* . stances, which have beep introduced, it is pretty hard to hang your hat on every thing, and the average' executive today wants to know exactly what is what, and. you cannot know that without concrete evidence. You have got to get definite informationand data. The appearance or the. findings in any group of workers exposed to a particular dust; or what have you, gives an accurate picture of the hazard which Ira existed over a period of years. That picture is one which the engineers cannot give you, because their dust counts or other deter minations may be only temporary or may vary from day to day. It may have changed considerably in the past few years; the hazard may have been for example, ten times as great two years before as it was ' on rite day the 'dost counts were made. So no occupational disease control is ade quate without initial examination of all When once you . know the facts, which employees. can only bfe obtained through technical . means and by experienced people, you can give, them something definite' on which; they can base definite conclusions and on .which you can base your preventive measures. CHAIRMAN JOHNSON: Dr. Sander has developed the need for the medical examination as a survey question to deter-mine whether conditions as they have ex isted have produced any pathology in the men. Let ns assume that, and install our CHAIRMAN JOHNSON: Now I feel program of control Dr. Greenburg, what assured that we Can discuss some detailed -do you feel about the need for periodicity problems. We have our base. We are in in the examination program? agreement that there is no ordinary occu- 1 F :pnal - disease hazard that cannot, be. i ;d with, that.there is sufficient evi dence to sort fact, from fancy, that there are instruments sufficient in quantity and kind for proper engineering analysis, and. that there is no need of guessing. DR. GREENBURG:^That would largely depend on what particular hazards were present in the plant itself. In certain. cases it would, be desirable to examine workers very frequently, perhaps even as often as once a month;-and in other in stances it might be very satisfactory to . Let us start now an occupational dis exajhine them once a year, depending on ease control program. We have Plant X. just what particular substances the work ' The management at the top says, "Find ers were exposed to in their daily occupa ,my hazard, if any. Control it, if need be. tion and how satisfactory the technical- I am setting tip a medical department; I. means of control were. , - am setting up engineering occupational . hygienists: 1 want you fellows,to wbrk obt For- example, in the case of benzol, it a program so that my. operating depart might be satisfactory to examine workers ment can install the necessary safeguards, every, three months. I believe , in the case whatever they may be, and assure me that of tetraethyl lend, the da Pont Company there will be not emergence of disability by . examines its employees about once a reason of these exposures." month, though l am not quite sure about that In the case of sand blasters,-it might , The Meffidd Program be desirable to examine them and x-ray ! .Let us build, first the medical half of them every six months; whereas in the that program. Of what does, it generally . case of foundrymen it might be perfectly consist,Dr, O. A.Sander? satisfactory if the men are engaged, in ; DR. SANDER: I am. glad you empha sized the heed of a medical program in an occupational disease . control program, ordinary foundry work to examine them once a year and x-ray them once a year or once every year and a half. aloiig with the engineering control. An It would be largely a question of judg initial examination of all workers exposed ment, depending on the particular occu- iPPJficcl.,ahc$*; >> ^5^5JljJPSSwCi?^V^w 136 28th National Safety Congress J pation 'and the particular substances em consider carefully- the opinion expressed ployed. there. You will observe that he has CHAIRMAN JOHNSON: I would like to ask Dr. Greenburg to amplify just one point. If thesurvey about which Dr. Sander spoke discloses no specific occu pational disease hazard as having caused any pathology--and that is the .situation that obtains in most plants--but still there placed the' burden upon his own profes sion, by careful discussion, of coars^, with-*the management that is to1 pay the bill; but the decision must rest with , the doc. tor upon the evidence as presented by die conditions of. the plant and the employees themselves. may be some moderate exposures to this There is no cook'boric formula which or to that, and the management wants to says you must, put employees through the be perfectly .sure, how often as a general mill at standard intervals. But thetnalting -thing should those men come up .for re of medical examinations js another thing. examination? ; .- * It always presents problems, because men frequently are. frightened when they Understand, this survey has disclosed know they are being examined to see if no pathology, no damage, nothing yoo can there is anything the matter with them, put your teeth in or hang your hat on as not just bring examined to. see if they indicating a great need for engineering are all right They are always fearful changes in current methods of control. tbit some dire calamity , may overtake . Rc-examination Periods DR. GREENBURG: That would largely depend on whether there were any hazardous materials - bring used in .. the plant. If the condition of the men at the time of the initial examination was quite negative and no hazardous material is be ing used in the plant, I should say the de cision as to whether or not you are going . to have physical examinations is largely them Soon. It is a real personnel prob- ` 'lem, one that fans to be. handled with judgment,.:.. I am going' to ask Dr. Cranch if, in Ids. long, experience ' of examining a- great many employees for operating exposures that might not be hazardous, he has al ways' been able to keep, those employees calm and collected, and. quiet* and, quite content with what things yrere found. . an open one, and a matter of wide judg DR. CRANCH: Physical examination ment. programs, for. occupational disease con For example, , in the case of a depart ment store's wnplpyees, where . young women act as salesladies, under ordinary .conditions; it might not be necessary or desirable to give them physical examina tions more than once in five years, per haps not even then. If, on the other-hand, the physical ex aminations were quite negative and yet tox^ materials are bring employed, the decision would depend on how toxic those materials are and what the analysis of the plant atmosphere shows. trol can hardly be divorced from a physi cal examination program aimed at general health conservation. Where' it is possible to have.a medical service, where the physi cian is in drily contact with the man, physical examination presents far fewer difficulties than where it is done only for. tiiie sake of occupa'tional disease.control,,:- . If an outride physican comes in to' ex amine certain groups of men at intervals of from one month to two years, men logically have a right to expect that there may' be something going wrong - with those who are called in frequently, and It seems to me that the answer to the that leads to considerable nervousness on question is a matter of judgment which their part as to. what will be found. must be based -on a comparison of the relative hazards of the' exposure as com pared with the cost and desirability of continuing intensive physical examination, and only by knowing the detailed facts can one arrive at a sound decision in a particular given instance. . There .is a matter of psychology and practice in carrying oat such a program of examinations. It is much simpler, where it is possible to arrange it, to lave reason ably frequent examinations for general. health conservation, -and'tiiese examina- dons, then, will be included in the regular CHAIRMAN JOHNSON: I .think procedure and help to determine the effects that it is very important for you all to of an occupational disease exposure. As Di tempt a a-fried.. The pa determii first,th< disease! coonecti daysgo Ourstructed a little seem tc slipping tiottt of require would i Anot! beris 1 .; not on stores h medical .patkina import: tablishi change - origin. CH/ ' portanl dng'fe is a tot because ^ pert so a medi for ab< ; Hire physici fold th fo the gram, augme other. Now and as in wb sulfide tor's o . about gones fested toms . tholog '"I 'vr what, them vahtag # it. <. t9 A SPiS Occupational Disease Control 137 Dr. Greenburg -said, we do not at- with', surveying to locate and find the , j>t:as Vrule a routine examination at hazard that they want to control. afixed interval cl a year, we will say. The periodidty ol onr re-exaniination is Will Willis Hazard disettss that one? determined torgdyby several factors: MR; HAZARD: It seems to me that fir*t, the possible exposure to occupational the most important thing thatthe doctor diseasehazards; second, whatwe notice in can tell the engfaeeriswhathis findings connection with that'man's health as the are from the physicalexamination. That days go by. more drless determines how seridns. the Onr supervisory force is usually in* strutted to send in any than who seems a little under the weather,.who does not seem to be doing weU, who seems to be hazard is; it often isofates.it to certain in dividuals fa the plant, and that points the way to places that shouldcome under engineerfagcontrol fa that regard. slipping a little. From their recommenda CHAIRMAN JOHNSON: Perhaps tions ofteu we pick up cases Unit certainly yon have already ;visualized what I am require examination which otherwise leading to. I want Mr. Bonsib to develop would easily have been overlooked. - that a little farther. Here we have the Another thing which we have to remem ber is thatmany' symptoms are common not only- to occupational disease expostores incident to fife in general; and the medical program for the control of. been- medical examination installed to disclose what is wrong; if anything. I. want him to develop the engineering-control method. What fact and what data does hr need to go about his business? pational disease is therefore extremely important-fa that the contact must be es Engineering Control tablished with the men to determine what MR. BONSIB; Since the amount, of -changes axe going; on and what is-their damage to the human mechanism depends origin. upon the exposure and the concentration, CHAIRMAN JOHNSON: The im portant ..point to. me, is that yon cannot drag' fa a physician from'the outside who jpi total stranger to.ydnr,problem, merely ^canse he is an expert toxicologist or ex pert something else, and ask him to set np a-medical examination or control program, the engineer should know the maximum allowable concentration to which he would have-to maintain the worldng atmosphere orthe woriong condition, and as an en gineer that is something that the.medical profession must give'so' that th'e engineer will have something to which to work. for about a week, and then depart. I think the answer to.the question, then, ! Hire him to. consult^ with your own physician, bat let yonr own physician so fold rite occupational disease program in is that it. is. very essential that the thresh old or maximum allowable concentration ' permissible be known. to the general health conservation pro CHAIRMAN JOHNSON: I do not gram, that the findings of the one serve to think we win quarrel abont that. I am augment and snpport the findings of the certain no engineering group will stick other. out its neck far . enough to define for the Now I am going to talk to the engineers! and assume that a survey has been made in which we have discovered a hazard sufficiently dangerous so that,fa the doc medical profession what constitutes the safe threshold Unit. It is not .quite the answer to the queation I had in mind, however. tor's opinion,' something ought to be don? . about it . I am. not. assuming that H^has gone so far as to kill men; but it has mani fested itself either in'moderate early symp toms-j>r: some actualdemohstrablepar thblogyinafew. ; For a groat many yean, yon know, the medical profession has been conducting its work successfully fa industry,' main taining the greatest degree of confidence between- the. employees and the doctor through the fact ' that the - doctor never I want to ask this group of engineers revealed what was the matter- with the what they want .the :tnei!ical men to tell maniftiierowabany them which they may use to utmost ad grades the men fa a.general way^-employ-- vantage in-their own work fa connection able, of employable subject 'to medical 138 28th National Safety Congress service, or employable in limited expo much dust It. bad been shown that sures. gypsum dost itself does not cause silicosis I'think I have blown open.a question here: Can the doctor inform the engineer of a sufficient number of facts about the hazard to which these men have been ex posed without weakening that professional or. injury tothelungs. Where there silica, sand, we look for thatinjuryto the lungs and'the development of fibrosis and silicosis where the exposure; is high and continued over a long period; of time.. confidence which he has established, in Consequently, where about, half of the' the workmen whom be is examining? material used in this operation was silica What I want this group of engineers to develop is: Can they use adequately mass information, or* information about the group, without having to know that Mike sand, it was. the guess of the engineer that here was a condition which had to be con trolled effectively to keep the dust concen tration down to very low levels. Dambrowski is about one month from To everyone's surprisedthe x-ray exami emerging with a disability? Will yon de nations of workers who had been exposed, velop that, Mr. Hazard?' to these operations for a number of years, MR. HAZARD: It seems to me it is entirely possible for the engineer to use showed that there was no development of fibrosis. the medical results in a purely statistical Further engineering data was collected, . manner. He does not have-to know who and it was found that two things hap is sick or whether it is Mike Dambrowski pened. In the first place, the grain size, or somebody else. It Is extremely impor of the sand was rather uniformly large tant that, he know the number of people and well washed.. There was no abrasive who are. showing the same ailment and action to produce a great number of fine the number of-people who are working in particles. . In the.air itself, the. concentra " the department or the plant as a whole. tion of free silica was . not 50 per cent; or MR. BONSIB: I do not see how you can protect against something unless you know what it is going to .do; and I do not see how you can provide necessary pro tective measures without knowing to whatextent you have to go on them. Yon.must" know the threshold limit to which the sub-, stance or the material, whether it is gas, fume or dust, is causing the trouble. If you do. not know what the toxic limit is, that is, the amount it .takes to make people sick or how touch the human mechanism can stand; making due allowance for the what it was in the main material, but only one or two per cent. Finally, laboratory examination showed that where you get quartz dust falling,, or where you would. get gypsum dust settling out of the air fairly rapidly, the quartz dust settled out more rapidly; and the combination of quartz and gypsum settled out even more rapidly than either one alone, due to the fact that the gypsum dust caused agglom erations with tiie silica dust. and yon had large groups of particles which caused this more rapid settling. .. idiosyncrasies of the susceptible; I do not Now, the data obtained, through the see how the engineer can provide the medical examination and the x-ray was necessary measures. ' - what gave tiie hint that the cost and the Therefore, I still maintain that the threshold limit is .the essential thing for the engineer to know. .That gives him something to shoot at. In other words, completeness of the control at that opera- - don was not as great as it -would normally be. thought to be by the engineer walking into the situation.' v" he must reduce that' concentration to the CHAIRMAN JOHNSON: I think that pointy below which it will not .make any- illustration binds together these various - one sick, and the length of exposure neces points. ,' sary to which that person must be ex I have watched that particular study de posed. veloped with a great deal of interest, and. MR. COOK: An instance might be cited where other factors than, threshold limits have been utilized. For example, in the gypsum industry, in certain plants for a fact, the engineers did not know, or did not have to know, anything about the men as individuals; the doctor kept that in his files completely. there is what is known as a sanded plaster Now let us summarise for just a mo manufacturing operation where there is ment, to see where we have arrived. We have t two to sangui Weld edge ; We ss gram gineex to be specia set. w amoui must gmcei fbrtoa shook tow tl it tea perfier bazar thing! natiot did a tions . in the Of contil toch< No .progr tiods cuss | - in .th scribi torn .. desig think grade mark and. i to pn Dr. thouf tailor engiti fit th DI not s tion < can.i your in th< By cent They Occupational Disease Control 139 jve the; doctors and the engineers as the ing what the requirements are of..rite **0 bases of bar triangle.' Oar panel feds State Code, without,knowing,the Emits to sanguine that hazards can - be controlled. . wluch the gas; dost, or- fame, has to be We know enough;, there is enough knowl exhausted, immediately sets about and de edge in the; aggregate to control. them. signs a hood. We say that fhe;'need for a.medical.pro gram: is as' vital as the need for, an en gineering program; (hat the doctor ought, to be the plant doctor, augmented by such specialists as lie needs to employ to coun sel with him; that they have a certain amount of factual information that they, must turn orer to the hygienist or (en gineer far htr use as a check for Hh per formances, and that the medical crowd should tell the ..engineering, crowd how . lowthehazard must be taken to consider Then, without even knowing how mudi . air can be handled, by that, hood; .he, looks into rite ;classified :secth>n,bf the telephone book and calls up the.fan company. The fan company has a salesman, bat he is not in, so the office girl looks np the technical data, and the comparer ships the fan. j When this ventilating.system is finally .installed, , the sheet.metal worker says, "Well, the sheet metal.work portion of it. is all right, and that is all! guarantee." ft reasonably ;stfe;: that the engineers are - Then the rim company, on the other perfectly willing and able to tackle the hand, says that the rim delivers a certain hazard in some fashion ff they know those volume of air at the -speed shown in their things; and. the periodicity of the exami catalogue; so they wash their hands of it nation to' find out whefhertheengineers And finally, when the whole'thing is in, did a job or not depends upon rite condi it does hot work and a job has been, poorly tions as the doctor finds the record written done. ; So the point I wish tomake is that , in the men themselves.. ventilation, no matter how simple; requires Ofcourse, the engineers are going to technical knowledge and technical instru continue, to use the instruments' of survey ments to determine when the system is to check their own results. really working. Now X am going down to our printed .program .and. explore some of. the ques-. 'fads suggestedmere.. The panel will dis-. -uss phases of exhaust systems. Are there. in .the engineering Catalogues, data de scribing machinery of one land, or another CHAIRMAN JOHNSON: I think Dr. Meiter has.put his finger on a very critical point When I 'ipeak about engineering, control, I meatMcngineering control, and I do not mean tinsmith control. Let me illustrate. to, make it possible for the engineer to Sandier talked about the metal fume . design an exhaust system if he wants it, or fever, zinc shakes. Visualize, if you will, thinks he needs it? Are there enough high the problem of a shipyard building de grade, glorified vacuum cleaners on the stroyers for the United States Navy of marketto pick one ont of the catalogue galvanized sheet plate, with a great deal and. install it in the plant, and expect it of electrical welding work to be done in to produce results? confined spaces, in the little tanks and cells Dr. Meher, will you develop your of which the ship is constructed. . thoughts on present market conditions of There is a plant set up in .the field, yon tailor-made exhaust systems as'., against might, say, lying for nearly a year at its engineering design of .exhaust systems to fitting-out basin, a little, plant abont 325 fit the ihdfvidna! plantcircainstances? ' *'* c * Exhaust Systems feet long.and 30-feet.wide, 25 to 30 feet molded depth and heaven only knows how many tanks in it (they get down to pretty DR. MEITERtln thy opinion,, there is .small sizes) with welding to be done in not available ready-made exhaustventila- most `In those confined spaces welding, tion equipment; The assumption that you steam-fitting and electrical work must be can select from, a catalogue and; Veniitate done. Can. you imagine a tailor-made ven yotfr problems has been a great drawback tilating system bfeing used there? in the progress of this work. Now let us go to the next question, pro-, By that! mean this: Oftentimes a con tective creams and lotions. Let us have cern will have, say, a local tin worker. clearly in mind that a cream or a lotion They call him in and he, without know- ` is smeared bn the skin for a purpose, aiid 1-40 28th National Safety Congress usually. the purpose is to. prevent the moderate amounts of something or other - from coming into contact with the skin. These creams and lotions are of two kinds, those that are water soluble for use in oily exposures, and those which are oil soluble for use in aqueous exposures. This use of cream, I declare arbitrarily, as Chairman of this party, is not in lieu of any other control These creams are used because controls cannot be made absolute, and because there are sensitive skins to be taken care of. Dr. Cranch, would you like to discuss the effectiveness and the use of creams, from the viewpoint of the doctor who has a cock-eyed purchasing agent who buys .an oil soluble when he wants a water soluble, and vice versa? Protective Creams and Lotions means of a patch test or by actual experi ence in the use of the cream. In that case, some other means of protection must be. adopted, or the man assigned to other work. . . The. great proportion* of creams now on the market appear to be reasonably free from any irritants or substances that ate particularly likely to bring about an.allergie reaction. The main thing is to select the one designed for the type of protec tion required. These creams, we have found, are often considerably abused. Men seem to think, in many places, that the cream has to be applied in a coating that by. its mechanical thickness to the qaked eye mil protect the skin. I have seen a man put on a quarter of a ' pound where half an inch squeezed out of :a tube would probably have answered the purpose. >* DK. CRANCH: I think you have In that case, they often run into other started something. Protective creams cer difficultly*. Many of these creams which tainly have a field in the protection of protect from oil substances, are creams skin from various irritant substances. I which have a soap base; the men are simply would put far ahead of the use of protec running around in a soap poultice, and tive creams, however, good personal they work up an irritation which is as hygiene and thorough cleanliness on the great or in some cases greater than.that part of the worker. Where that is ob which would have resulted from the ex tained,. the question of protective: creams posure they sought.to prevent ' is of lesser importance: sometimes nega In the oily cream preparations which tive importance. , protect from1 water soluble substances, There are certain exposures, however, they offer us very queer mixtures. I^no- where no amount of personal hygiene or line as a base, I think, is the thing of cleanliness is enough to protect from pos choice for that type of protection, rather sible harm. Therefore, we do have a place than a petrolatum. It works1 a little fur for protective creams of the two classes ther into the skin, I believe, and will pro Mr. Johnson has just mentioned. tect in a more thorough manner than the Primary in the consideration and selee- tion_of any cream, of course,-is. the nature of the exposure. If it is on an oily sub stance, we must use a water soluble, cream which will form a coating over the skin and resist the penetration of the oily material. . ' And, on the other hand, if it is a water soluble substance from which we must have protection, we must , have an oily base in the protective cream. * petrolatum base preparations which just smear over the surface and are more easily rubbed off and fail in their protec tion. Another thing to consider is; that .the last word has certainly not been said on protective creams; they are in the process of rather rapid development T believe there are' commercially available many suitable types of protective creams, and. on the other hand,, they tan be made, up for a specific purpose very satisfactorily The first consideration, then, is that the on the advice of your physician. .You can cream itself shall, not contain an irritant. get a very satisfactory cream, that can be That incidentally opens up the whole field produced in'bulk forypur own use. of allergy. There are many people sen sitive to certain of the common ingredients ' Respiratory Protection , used in many of these protective coatings. CHAIRMAN JOHNSON: We will They can probably only be discovered by continue with the discussion of respire*. tbry exan men, dons knov baa i tecte the i proti of re I meat dial is a if I whet exan type wiUi D1 blast met: fort! helm and i theh in blast yet t who met. stag* cosi's case been W. . mod* anyo (act. shift! his i givin ; at h As are * visafa are a bans) sand must pers . ever, othei that wash - watei Wi Occupational Disease Control 141 ttory protection. In connection with the no need of respiratory protection, provided A Wminetion of thousands of foundry- an exhaust system is used and is in proper ^ men, Dr. Sander hal explored the opera- working condition. dons which they conduct, so that he knows what they all mean. He of course has found that some of the men are pro tected by exhaust systems, and some of the men are protected by personal body protection, either filters or the airline'type of respiration. The . exhaust ventilation for swing grinders is a little more difficult, but it has been accomplished. There are very few swing grinders in Wisconsin that are exhausted, however. It has been our ex perience that swing, grinders have not de veloped as much silicosis as was at first I interpret respiratory protection to believed, and the reason probably is that mean the kind of respiratory protection by the time they get the.castings'there is that you. stick onto the man.; Of course, it no-more molding sand oh them. It has alt is all respiratory protection, but I wonder been removed , first in the grinding wheels if Dr. Sander would like to discuss with all the artificial abrasive, so the only whether or not he has found by the actual silica the swing grinder is breathing is examination of men that the satisfactory generally plant dust type of respirator has been found which will actually protect the men. Holders and core makers need no spe- - DR. SANDER: .Beginning with sand blasters, undoubtedly the modem air helniet affords almost 100.per-cent, protection for the prevention of silicosis, provided the ' . cial respiratory protection,' in my opinion. 4 molder just could not do the job very well if he were required to wear a respira tor from morning until nigHCT;. helmet is kept in good working condition, and provided the air pressure coming into the helmet is satisfactory. . in the observation of about 300 sand I do not think'I would-depend oh a respirator for the protection of the man with the tuberculous scar. I would rather move him to some other job, or move his 1 \-t blasters in a seven-year period I have job' somewhere else, or localize his job in yet to see the. first one develop silicosis a separate.room and ventilate it. who had worked only with the modern hel & met. Also, 1 have seem no so-called first- 1 see no reason why we should worry * jage cases develop a second! stage s3i- about a sand blaster today,, even with a Jowi- daring that interval. A first-stage tuberculous scar. We feel they are not case has been kept at work; he has not going to develop silicosis, and therefore been shifted. - we think that what little dust there may We feel that a sand Jbls#ter with- a modern helmet is brcathbtgr less* dust than anyone else in the foundry as a matter of fact, and there is certainly no point in shifting him out onto the floor, removing his piece of respiratory protection, amt giving him more dttst than he is getting athis sand blasting job. . ' be will have no effect on.such a tuber culous scar. We have not permitted sand blasters with tuberculous scars to continue working on that job, but I think we should permit them to do so today, knowing that the hazard of sand blasting is controlled provided, of course, the equipment is kept in. working condition. As far as.the other foundry operations CHAIRMAN JOHNSON: That dis are concerned, of course it is always ad- . sertation answers beautifully the question visable toexhaustwben possible. There . of respiratory, protection as far as it ap are a few occupations 'that cannot be ex plies to the foundry; and I; think direct hausted satisfactorily. One. of these is ; analogy, wilt carry that opinion over into sand chipping, and where sand chipping almost any other exposure that you choose must'be done/ it is advisable for the chip- to carry it into. i! !! pers to wear, the .filter respirators.. How ever, even there it is advisable to try some other ..method.'of cleaning the-casting if that is an that is feasibler-for instance, washing with high pressure^combined water and sand, and so raQK.y With ordinary stand grinding, there is In order to play ajtsolutely fair, with everyone'in the. audience, I am going to start on the questipns that have come to me,: and there are quite a number. . Here is the first, question: Assuming that- the development of adequate engin- it 142 28th National Safety Congress eering and mediral departments is essen 'could: not let 9 state man into, .the plant tial to properly -, control dost. hazards, without expecting himto.change a recom how can the. smaller plants, those- having mendation into an order overnight. fbave 100 or 200 employees, cope with this prob not seen that in thistreatment ofthe occu-' lem and detenhine' whether or .not they pational disease problem. I am not telling have a hazardous dust condition or any you that it does not. exist; I. say I. have other occupational disease condition? It, notseenit , would be impossible in many cases for I have here a question for otir engineers. these small plants to set up elaborate and expensive control departments. Yesterday, they were talking, abont weld ing metal and fame fever, and so forth. To:lead the answer in a definite-direc Here is the'question: Does an exhaust tion, I am going , to suggest that perhaps system from electrical Welding affect the. the answer-.lies in the'' recent, development type of weld? ' in almost every industrial, state, divisions . of -occupational disease hygiene, either in the Department of Labor or the Depart ment of Health. I am sure Dr, .Leonard Greenburg would like to answer that question. As I view this question,' it. means this: When you. wdd With .an dectric wdding process using acotedelectrode,the flux-1 ing of-the coating produces unumbrella . or tent over theWeld arc itself hod thereby. excludes the air from the arc.and prevents <. The Small Plant Problem . oxidation of the steel which Is bring cast DR. GREENBURG: There are two things that the smaller plant may do;.,one Is to make use of its insurance company into-the hole being filled tip, and prevents oxidation, of any of the material or metal that is in die fused state.- to the.fullest extent; and the second is.to Now the question is, ifyou stick a heavy make use of such facilities'as the state has exhaust there and poll away that vapor at its disposal, either the Department of which 'provides .the protection,- do you Labor or the Department of Health. ruin your' wdd? Is the control for health In approximately 30 states in the Union, at the expense of the wdd, or would it be there are divisions of industrial, hygiene in cither the . Department of Labor er the better to forget that and limit the tone of the welding? . ,'' 11 Department of Health, and in a few cases Does, anybody here want to answer <n both, and they arestlways prepared and' that? -.. -- eager to help the smaller plant; partial-. larly with .such problems as tins. MR.BONSIB: I think that if you have general .ventilation there would be very Many of the insurance companies have little danger of destroying .that umbrella developed divisions of hygiene and have that Mr. Johnson< hasmentioned.Of experts on their staff* who are. also pre- coarse, it is advisable -.to.^raaMfye^rapse . pared and able to render service along fumes as hearthesource of originaii pos these lines. .It seems to me that the-big- sible. Youhayetoget Within rigbtindies, gest problem is to get the small plant and not more than thatv to rda^r gelt effi- management to recognize that the stum dent results, and being that doseybudo bling block is management itself.- Once that recognition has been achieved, it'is a relatively ample Hung to obtain , prac tically free service from either of these two organizations. in an effort to really do constructive preventive work. " hot require more than 100 or 200 lineal feet per million. . J do not think there is. enough ,cooling action to: do damage. As. a matter of fret. some "tests we were interested in .making seemed to indicate that there was no dam CHAIRMAN JOHNSON: Let me add age done. .Hpweverryoucomewheretbe one thought to that answer. I am familiar damage would be done if youexceed that ' with most of those- divisions. In none of but I do-not think you need to exceed lOO them is there anybody carrying a big or 200 lineal feet per lhilfioa. ,Tf.yoti have - stick to browbeat or to hammer into shape geneml ample ventilatloii, then you do the small plants that .want help.. They not have any danger; inWiy opinion. - are already giving help in an advisory CHAIRMAN JOHNSON: Thai seems fashion. to he a logical condusiom It is certainly There has been fear, lit times, that yon' an opinion based upon observation of that sort .of "Is ti fire t>ri : ; In- ot towfei and its descend the fin throng! onthet ' Mr;:: to'talk fire efr rich let which knoW.t silica. MR. a-medi .fire bri anded It s brick. 3 the.ch fryer s coasidt .hazard calridt .-'.CHS of the of 'the handle DR. this.<3 &S$*sSSP9Kn * .I soit.of problem.. The-.next.. question Is: ran-of fire days; but. I .am not giving the Is there enough sillca in theaverage > medical answer. It' is my thought, that ore thick to effect workers' seriously?" the hazard; produced in >the. day. products is not ah inherent one,' but. one thrown in : ! Inother words, if Weexplore clay for . by violent* agitation due to dry grinding itsrriractorypropdrty on ihe one band, and xjts: plasticity-on the other, is there a - operations. 1 descending order of riticosis braird from the fire brick -.on the one- side^ down JLetus goon toanotiierinterestingques. turn: "To wliat extent are the industries through -plastic china day or paper day with which this, panel are familiar pro on theother? viding washing fadlities, and what are.the advantages ofl.washmg in showers,, and.so. Mr. Hazard, -the questioner Wants yon forth, accruing tothe employees on the one totrik abbot die amotmt of. hazard, in the hand, and the employeron the other> and - fire clay, and for want of a better defini .how is the thing paid for?" .. tion let us leave out the Ganister brick -which is a brick1 the: sand. of which'; we. Well, we' know that in some ' states, .know, to be pretty dose to 100 per .cent washing ^facilities are required by law in silica. - v . .-a-'v certain lypes' of-industries, and in others they are put in. MR. HAZARD: I think this is really a medical question. But there are .certain I can visualize the need to'develop this fire bricks -which are very high ui silica, question, in two. ways;, one for-the con and certain bthers which havepractically trol of a serious occupational disease ex none.or. a. negligible amotmt in them. Yon posure such as lead;.: and the other, the have..a rangethercfromwhat might be- general iadustrial hygiene, to get folksto cailed a dangerous condition, down to one ' wash pn the developed fact, that by care where yotuare practically sore no 'danger ful washing a greatmany of the dermatitis problems solve themselves. ''*** & It seems .to me that ifyou bad a- fire WillDr. Cranch talk about the pro bride, with veryhighsilka Contend ,with vision of washing facilities? the, chipping and - knocking of the brick-. DR. CRANCH: .Washing facilities are layer ragainst'.the brid^ ifr niigfat stir up most desirable things in any plant, large "Wade-cable dust and might be. a sQicosis ' or smdt As flie Chahmum has said. It is .lard,' but: I;would like tohearthe inedi-' rite , most important factor m the preyeh- cal side on that question. : tion of occupational dermatitis, to say ; v CHAIRMAN JOHNSON: WUl either nothing of general hygiene'to :the work ofthe doctors discuss the inherent toxicity' men. of the fire days astbeyare normally The .ridsritades-of trying to establish handled ihthe manufactoreof brick? any adequate washing facilities' in in pBL GREE^iBURG: ; It sterns-to me dustry. are -.great: ' My. first experience the-Ouunhahpo&it-.totelluswhat the occurred over'forty years ago. as a work* pereentage of freesilica isin the fire day. man. In that plant there was no.-Water '''HeVbaa-'tuked:atoandthe question, but available, althohgh it was a large plant, hehasnot told ns 'the ernx of the whole and titdesk you sneaked from, the job and problem. - *- ' went around to a faucet which, was used - CHAIRMAN JOHNSON:1'The prpbA . for sprinkling the front lawn, you had ho lemseemsto mev,tb be-; fdafedT; to /the notionthatmaybetbese mixturesare so mixedtbat otitorthings beride/thd rilica prodnce . ah alleviating or. riiramefibrat- water avrilable. lt was'hot expected that hands should bewashed. A man worked at his job, ate his lnnch, worlced all day and went home so black asa rule you iogl efitct topteveht what siHca there is could hot Itril his race. 7 from causing silicosis. . Later I . became much interested in the ' Gay*;doMot;seem tb produce silicosis. develppmient of wasfaihfg. facilities. I. re It is ;the dry-pan grinding of 'all lrinds of member in one very large plant we put things f^t .pnidnces:^ quantities in excellent washing' facilities, and it was of dnst. sdme'of;Which contain silica; and surprising to see how they were abused I- cannotremember atthis moment just even to the pomt where m some, cases we what the aihbunt of silica is in the ordinary bad to discohtihue sendee. In other or- . 144 28th Notional Safety Congress ganizations, an attempt on the part of May: we. have a. development of that die management to furnish good washing question from Dr. Greehburg? ' facilities met with consistent refusal on the part of the workmen to cooperate with them in the use of these things; even where the workmen were given time ont at full pair on company time to wash, they would not do it. DR. GREENBURG: In dealing with the whole problem ,of dermatitis due to the use of cutting oil,: you. .are. dealing with several different factors which may produce different .types, of .slriu lesions. The cure for all of these, it seemato nut, Fortunately, these conditions have changed, and the men themselves now ap preciate those facilities where they are. pnt in, and they generally demand them where they are not pntin. lies in the use of proper protective oint ment before the' men start wock in the morning, and the washing up at the end - of each shift with the proper type of honirritating soap. . I think washing facilities are a most im portant feature in the control of occupa tional diseases, and a number of occupa tional conditions aside from dermatitis. There are a number of occupations where complete showers are furnished and those facilities are very largely a measure of prevention of occupational disease; and at the beginning of the day's work the men change to working clothes where previously that was not done. The easiest way to get the men to use a non-irritating soap is to supply one so they will not purchase an irritating ' soap themselves. If yon leave it to them,, they may purchase one which seems to: work rapidly, but which may have irritating properties. Oh the. other hand, if the management supplies it, they can purchase one of suit able .quality which in general may be of a more satisfactory type. . Oil Dermatitis ^ r ' vThe whole problem of oil folliculitis xand. oil dermatitis can be handled and is ' CHAIRMAN JOHNSON: Here is another question: Handled in many plants on a very satis- . factory basis, by these simple means, and so far as I can see does, not present any "Is it not an accepted fact that oil insurmountable difficulties whatsoever. dermatitis is more of a mechanical break- The usual defect in the system seems to } down of the skin than it is a toxic prob be that the plant does not .pay any atten-: ' lem? How would you overcome the de tion to the problem until many''of the sire of the employees to use abrasive men become infected and many of them cleansers on the hands?" . have skins which, are more or. less mined Cutting oils and other oils produce dermatitis, and represent three hazards. One produces a plucking of the hair follicles, which is largely a mechanical thing of rubbing oil and dirt, or what have you, into the skin. by an accumulation of oil and foreign matter in the pores of the skin. At that time, preventive measures are no longer suffidebtX It then becomes necessary really to cleanse the skin thor oughly and repeatedly so as to once again ' bring it back to its normal clean condi- Then we have what I think the doctors . tion. call . heterothema, which is probably a CHAIRMAN JOHNSON: Let ns go chemical burn, an irritation of the skin over to the engineering side and talk on which is another type of dermatitis. Then the industrialist who manufactures oils to there is a third one, which produces blood providehimself a meal ticket and tries to poisoning or boils where, the oil has been prevent)just this hazard from gutting supporting an infective medium bacteria trouble. of some sort. ' : . MR. BONSIB: I agree with much that . Can we. solve that oil contact problem the doctor has said about getting good by handling the washing of men in a satis oil in the lirstplace. .... factory manner through washing facilities, and the discouragement of the use.of harsh abrasive soaps, or doesn't it make any difference? /I think that one of the big causes (and I have studied this problem a lot for the reason that you hear many stories of"ifl- ' juries due to cutting oils) is that the oil 7 .is no ched use a again metal skin, tiier i Ido It the^< -again the Cl 'quest work ' patio and i - ignoi D1 : ploy* ' towl be-in natk any. - what ployi knov for -1 diffei is. in futui T1 .Tan a du . emp! trial . deck amir term that Ploy - the* T1 ^ it is imp* wroi port . A:v blob is tc tug and C any! tod mot \ rarqrr?i<7i Occupational Disease Control * 145 .is not kept clean. In the. cases we have tell the .man,'; than.in any other way. He checked tjhe.troublehas been da? to the may imagine.he .has something, and he Ise of dirty oil, oir using oil over and over. worries and worries. and finally becomes a again: that is filled with small, particles of victim..of what is known as autobypnosis, metaC These' catise'small injuries, to the skin, and. that in'torn, brings about fur ther damage-So if you keep the oil dean, I do not thinkyonwjll have much trouble. I think the practiefe of men spitting in the oil and tiring the oil over and over - again .has caused much more damage than the so^afledparaffinacne. f CHAIRMAN JOHNSON: The next question is tide: "Should employees -working m departments subject to occu pational disease hazard be acquainted with and informed of these hazards, or kept in ignorance of them?" . whatever that is. V* I think by relieving his mind and telling him -exactly'what is-what,' yon lift that worry from him and-yon ease his mind, all of which' makes a better man of him. CHAIRMAN JOHNSON: Now let us tackle another question: "Processing of a certain cellulose product involves over night soaking in a solution -of .5 per cent formaldehyde, and subsequently consider able formaldehyde odor is given off during . the drying of which those in. the vicinity often complain. How much formalde hyde would represent, toxic proportions? OR. SANDER: Undoubtedly, em And how could the quantity present in the ployees should beinfonned ofeyery hazard airbest be determined?" ' to which they are exposed, and they should be informed also of the findings bn exami nation. Anyone going to his doctor, for any. reason 'whatsoever, wants to know Dr. Mtiter, would -you like to tadde that problem? DR. MEITER: In my own experience, what was found. In the same way, an em formaldehyde is irritating enough so that ployee going to a plant doctor wants to -yon;would not require refined technical know what was found. He is not paying instruments to make determinations, be for the examination; but that maltts .no cause it is very easily noticeable In'low difference, he .is still a human bring who concentrations. I think proper engineer is . interested in -his own-health and His ing methods could be-devised for elimi future: years of gainful employment nating the -fames without using technical \ . The practice in Wisconsin with physical' examinations has been, to give, employees a duplicate copy of the report which the employer receives. The 'Wisconsin Indus instruments,because it is necessary to keep the fumes down to very low concentration, otherwise i dermatitis may develop and also sore eyes. . trial 1 Commission - recently published a CHAIRMAN JOHNSON: Does the declaration of principles on physical ex medical side of our panel wish to develop aminations In industry which everyone in that any farther? terested in this problem should see. In DR. CRANCH: 'I thinkthat question that it is specifically requested .that em illustrates one of the phases where it is ployees be given a copy of the report which the employer receives. That is not a complete record or report; ft is merely.a statement or listing of the important defects.; I. believe that- it is. as not necessary to have engineering help in order .to determine, whether or not you haive Reached a print of,safety. Formaldehyde vapors are not likely to be toxic, since in a concentrated form it wrong to. give employees complete re ports as. it is to giye them nothing at alL A worker is not.interested in what his blood.'pressure,reading was yesterday or is so irritating that just for comfbrt.sbme relief would-be demanded, so that we need not be particularly concerned about what concentration is obtained. ' today; he is merely interested in know There are-a number of chemicals. of ing whether or hot it is significantly high, that sort, where the immediate effects are and that bail he ceres about so irritating that toxic. exposure would CHAIRMAN JOHNSON: is there usually be avoided In the course of ordi- ` anybody^ else.on the panel who would like nary good practice In handling the ma- to discuss the question? terial. .-M'R.BONSIB;' F think-yon can*cause CHAIRMANi JOHNSON: Warren more unrest through fear, :by .failure to . Cook says he has another idea. ill; .1: 28th National Safety Congress MR. COOK: The literature does con thing like that/ If an employee upon ex tain some iflformationconceniingthe de amination shows a veiy: slight increase velopment of irritative actions, and we of lead content above normal afteir sixteen are wondering in Connecticut whether the years' exposure, would', yon change, his concentrations' which were -listed in the occupation? . literature and the irritative action was as sociated with a tolerable amount of irrita tion^ or whether it was in the higher de DR. GREENBURG: I wbuid want to know where he showed it, and how. grees of irritation. CHAIRMAN JOHNSON: If I may We ran some analyses on some formal dehyde gas in an operation where formal dehyde was.being used in the manufacture of synthetic resin. The method we used was the bubbling of the air of the plant through water, with -two babblings in a series, and tested with Shift's reagent, die answer the question; it. seem*logical that if there is lead showing up, it came, from somewhere, and having explored that yon can determine , the engineering phase of the control, and perhaps he can stay on the job after you have controlled the-lead - fumes. .' regular method for the determination of Mr. Cook; won't yon answer the follow formaldehyde; and we got results that ing question? "What, instruments are were in the area of die breathing zone of there on the.market which are reasonable less than 20 parts per million, which is in cost for small, shops to purchase which usually suggested as a satisfactory con can be used to check atmospheres in metal centration. . spray work for zinc, iron and other harm At one point we ran it np to 90 or 100 ful fumes? - Must several instruments be parts per million, and at that point I found - used; where- .many types of metals are I could beep my nose there for thirty sec sprayed durihg a working day?" onds before I decided to back away from it. Metal Spraying Equipment But I do agree , with Dr. Cranch and MR.- COOK: On metal spraying,'there Dr. Meiter that where the irritation does are several angles. No.1, a booth, a ven get excessive, then, the irritative ,gas -'Can tilated booth sbould be used where pos be taken as the determining factor even sible. Secondly, the man shonld in' most thongh with most of the materials the. cases be given. a positive pressure air irritation is not the safe way to .determine supply. whether a gas condition is or is not safe. Now, assuming that the particular CHAIRMAN JOHNSON: Hera is operation is one in whieh the man may be ' another question: spraying brass, there are various methods "Is sulphur dioxide gas in concentra using the ventilated booth: Let us assume tions as low as 10 parts per mlllioa for pro for'the moment that he is provided* with longed exposure .considered hazardous to the health?" no respiratory protection. If a man is spraying zinc and the booth is. providing Going to the medical side, will either Dr. Greenbmg or Dr Cranch tell us if sulphur dioxide in such low concentration . represents a hazard for continuous expo sure? adequate exhaust so there is not much of a cloud of zinc and he dobs hot get. metal fume fever, it is probable that it is hot necessary to make any determination for zinc. .If during the course Of the'day.the man is spraying some lead aind some cad DR. GREENBURG: I cannotsay off mium, I would feel Very definitely that hand. It is jnst about on the borderline, it would be well to run an electrical pre I think.* cipitator sample, analyze the sample, and CHAIRMAN JOHNSON: Now, if an obtain the electric precipitation for lead employee upon examination shows a very and also for cadmium which would be a slight increase of lead content above nor routine chemical procedure, and the con- mal after sixteen years of exposure, . centratibn of both of those should be kept would you change his occupation? below the suggested toxic limit in order I do not know what a "very slight" to assure that you are on the safe side. amount of lead is. .1 think presumably I would fed that it would not be neces this means a few stipple cells, or some-. sary to analyze for zinc under those con dition .there ticnlar yon d< minati based get ai duratii metali DR. and I isfirs booth the ot The pressu operat iztng. withoi where going believi right by prc man, sampl CH. sperifi Occupational Disease Control 147 editions, or for other of'the metals unless here is some additional one that is parWlarly toxic. Bat- particularly where you do have lead or cadmium, the deter mination should be. made for those, and - based upon those determinations-you can get an idea on the .basis of the relative . duration of spraying of those particular.metals what the exposure is. - DR. MEITER: I agree with Mr. Cook, . and I Believe the solution of this problem is first, the use of a properly ventilated booth so al to eliminate the exposure to the other workmen, in the vicinity. - - The second item is .the use of a positive pressure '-airline respirator to protect the operator. I think that conducting metalizing operations all . over the shop- and without adequate equipment, especially where such metalsas lead are sprayed, are going to produce occupational diseases. I believe the proper thing to do is to start right with' the proper type of equipment, by providing the booth and protecting the man, and yon will then cot need the sampling devices. CHAIRMAN JOHNSON: Then the specific answer to the question seems to be the lead.predpitator as the one gadget that will be most useful, and the sample should be analyzed quantitatively in the chemical laboratory. I want to ask the . doctor a question in connection with pre-employment medical examinations.' The exposure is .something that may cause dermatitis. I take it from the question that the problem of allergy arises. Do you recommend patch tests in conjunction with pre-employment exami nations to determine an employee's pos sible allergy to the exposure? DR. CRANCH: In general, I would say you would hardly be warranted in con ducting patch tests on all applicants for employment. .Where we have a known material-to which the employee is . being exposed that very commonly .produces an allergy reaction, it might be advisable to use such a filter. Patch tests are not 100 per cent infallible, and they are not alto gether staple. They have to be very care fully given, and very carefully interpreted. For that reason, .they are not an integral part of an average preliminary agreement' upon examination. They might be quite misleading. ADJOURNMENT