Document 6rkOq0dZ64Y6K8ozRz5ve5e1

I 6 Transactions of THIRTEENTH ANNUAL MEETING 'I INDUSTRIAL HYGIENE FOUNDATION OF AMERICA, Inc. November 18, 1948 f INDUSTRIAL HYGIENE CODES AND REGULATIONS W. P. YANT, Sc.D. UnM l lwl I Dmlinnl. MIm Uali Aiftwit timi Connotation anil (lie suggested implications of u subject are un avoidable elements of very ini|Mirlanl influence on 11 person's tliink When dculiug with industrial hygiene codes, it is, therefore, necessary to condition the mind, by deciding whether one is to think of n code in the strictly legal and regulatory sense of being "u body of law established by the legislative authority of the stale, and designed to regulate completely, so far ns .statutes may, the subject to which it relates."--or whether one is thinking about codes in the ordinary and more voluntary sense of being "a system of principles, rules, or regulations relating to one subject, or a formal statement of them." The preference of the speaker is the more common and voluntary sense with a minimum of regulatory provisions. There is niiieh evi dence that a desire for a concept of a maximum permissible freedom in the rules of life is shared by many persons. It is hoped that this will be a continually increasing dominant influence in the formulalion and administration of all codes. The real usefulness of codes is inherent in their compilation of good knowledge and dcseriptioii of good praetiecs pertinent to a par ticular subject, their contribution to education and understanding, the basis they provide for measuring and comparing the results of endeavor, and their effect, whether voluntary or legul, in ullaiiiiug good practice. Codes, Imtli written and unwritten, have always been an essential factor in the progress of civilization, and are no less so to industrial hygiene. Development of Industrial Hygiene Codes Industrial hygiene codes of one form or another are not new in this country. Some of the trades and industries have voluntarily formulated cm lea of good practice. I likewise, Rome of the slates have had rather long experience in this endeavor. A discussion of the prac tice and experience of the Stale of N'ew York was presented by I IrenImrg' at n previous session of the present meeting uf this Foundation. However, most of the industrial hygiene code, endeavor among the slates is a comparatively recent activity. It has paralleled Ihc rather rapid growth and acceptance uf industrial hygiene praeliec ns a [1 iloirahle and necessary part of the maintenance uf health in industry. The endeavor is a rather natural product of the accumulation of knowledge mid experience in Ihc control of occupational hazards, and Ili>* realization that the circdive tcchniipics cuulil la* promoted and applied nmre broadly in industry, if they were organized into sys tems or codes id good practice, (.'uuxc|ueiitly. considerations uf indus trial hygiene codes are no longer those of desirability, need, and usefulness, but are those of incorporating (be best knowledge into emir* that are ndci|iiule. reliable, and practical. Ill accomplishing Ibis, however, il must lie realized tliul the development uf these codes is necessarily based on current conception* of need and scope, and upon current knowledge with its many existing areas of indefluileiiess and deficiency. Qualities of adequacy, reliability, and practicability cun lie only relative and conditioned upon the current understandings. This emphasizes tlint the development uf industrial hygiene codes must lie considered from both I lie Rlmrt range vicw|miut of incorpor ating the best present conception and reliable knowledge, and I lie long range viewpoint of providing means for prompt revision to include new concepts, needs of changing conditions, nod Ircttcr knowl edge. Further. codes must be ndiiiinislcred with a full understanding of their limitnlious. Authority for (he Development of State Code* . A comprehensive review of the authority that exists among the states aud other agencies in this country for promulgating uud enforc ing industrial hygiene emles. with a discussion of the general nature and trends of the existing codi**, their weaknesses aud deficiencies, and the need mid suggested content uf a uniform code, was presented at a former Annual Meeting uf this Foundation by lUuuuiUeld.1 The general Hiliialiou as presented at that time lias nut changed funda mentally. There has Imvii an increase in the number uf stales Hint have industrial hygiene facilities with only Iwu now remaining with out them. The ubiiiidiim-e uf Hitlliurily and |mwer among the stall's uml territories to promulgate and enforce sueli codes, rules ami regu lations, remains. In alsntl onc-linlf of Hie slate* Hie power is broad, ami in Ibe remainder il is by specific legislation. A large majority of Hie slitlcs luive industrial hygiene emles of one form nr auutlier. Subject Mailer uf Present Slule Codes The subject mailer of Hie stale codes varies widely. It ranges from little more Ilian general sanitation, to increasingly broader coverage lit rough attention to chemical and physical agents and filetors of enviroumeiil. More or less singular attention is given In the [Cl cui|tl<>yiiit'iit of minors. reporting of cases, employee mill employer responsibility, ami specific hazard*. Tin- majority of Hie codes lime IiiI>1ex uf iillovvnlilr cniiceiitratiiiiiK of atmospheric cinilaiiiinnnls. These lalilca vary widely in scopo ami lo some extent in the values given for the limits. The liniita hare legal status in alamt imc-hnlf of the slates; in the remainder they are suggested hygienic slniulnrds. Weaknesses of Present Stale Codes There lias been no very iinpnrtant remedy to the weaknesses and deficiencies of the codes that were pointed out by liloomficld.* The variability and diversity of content continue tu make it diflieiill In develop national policies for safeguarding the health of industrial employees. This is of purliciilar importance to industrial concerns that operate in several stoles. It is also important In designers of structures, equipment, ami processes. In trade associations that carry on health activities among their meiiihers in many stales, and in fact, to all interests. Many of the codes do not have guiding principles lo assist industry iu achieving good working conditions; also they are inadequate in providing specific information which would show indus try how it can comply with the code requirements. There are many areas of iifdefiiiiteness and inadequacy which hinder good adminis tration. 1 There continues to he u multiplicity of agencies within most of the states with authority to promulgate ami administer rules and regulations pertaining to industrial hygiene. There are few slides that have less than two such agencies and some have five nr six. In addition, n single one of these agencies may have a dozen or more separate and sometimes emillieliug codes. This overlapping of ouilinrity anil purpose creates duplication, confusion, and cnufiict among the agencies, and creates problems for the employer and all others concerned. The variable ami diverse nature uf the present stale codes is a rather natural product of (he power I lint exists within the states In promnlgale ami ndministrr such regulations, ami the rigid of each state to promulgate a code of its own choosing. This Ims resulted iu a situation which, although undesirable mid irksome, has provided a grand experiment iu code preparation ami administration, the results of which have liccii very substantial. There have been conirilnilinns to better working conditions, In elicitation of attention to industrial hygiene practices, In the desired scope, elm racier, and administration of .such codes, mill lo Hie ileleniiiiialiou of areas of deficiency. It appears, however, that this naliirally occurring experiment has prac tically served its purpose mul that real nlleutiou should la* given to I'dlJ improving the eiale situation. Although some peculiarities of occupa tional exposure to harmful agents may is'eitr among the steles, the uiiiety of processes mid agents, ami the opportunities for exposure are generally similar, and there appears to he only minor need of specialization or Iniloriug of codex lo meet specific slate requirements. Karl low. if the industrial hygiene codes are to la* representative uf the la-si knowledge, practices, and scientific data, it is a sound expec tation I lint they would and should la* far more uniform than they arc at the present time. Their divergencies alone condemn them. ACC;III Model Code It lots been mentioned that a part uf IHimmlieldV-1 discussion per tained to it pattern for a model code Hint was designed lo remove (lie undesirable fealtires of the existing code situation; also, that a Coininillee of the American Conference of (invcriimoiitnl Industrial Hygi enists (ACOill ) wax engaged in the drafting of n eiale along the lines of the pattern that lie presented. The aims ami objectives of (his )>iitlei'ti were hriclly, a code that was adequate, practical, ami Imsed mi M'iciilillv fact; aimed to inform uimingciiicut wlmt itx responsibili ties are. nml limv safe mul hcnllhy working rnmliliuux may la* iicliievcd; mul su worded to take into consideration various social and eeumnuie aspects of the problems. Some of the more specific features were to provide reasonable guides or principles which would enable industry to maintain the health uf its workers at a high level; to reconcile Ibis endeavor with the aim of industry iu achieving maxi mum production at minimum cost; lo contain rules and regulations for the prevention nud control of occupational disease; to consider (lie hygiene of ladli the working place uiid Hie individual; to provide a legal iiiterpretniiou of the rules and show industry how these rules can lie met by gintil industrial hygiene practice; and other information that is pertinent ami necessary lo the priietieul application nml admin istration of the rode. The Committee of the ACIIIII that lias been working on this model code released a draft several iiioiiHih ago that emlHidicd the results of its deliberations ami study lo that date. Copies were sent to representatives of a cross-section of interest iu industrial hygiene for review, coinniciil, nml criticism. These reviewers included indus try. labor, insurance, the public. Hie professions and practices in volve!I (medicine, industrial hygiene, mul stiffly), nml tin* ineiiilhws of the A Ctll It. 'I'lie selection of reviewers nml conveyance of I hi1 draft were liimle in part directly hv Hie ACOIII and iu pari hy asking the Ainericun Standards AsHoeialiou to communicate with a group of interests of that Akmm'Ui!ion's selection. It was originally suggested dial die speaker direct a (inrt of liis present discussion to Mime of tin* features of this first draft of die iiinilel rode. However. evenlK have oceurreil wliirli i|i|iear to make any extended discussion of the first draft inii|i|iro|irinte. He is informed flint the many eritieisiua and eoninients that wero received in response to the eireiilatiou of the draft have been Riven serious consideration by the (lode Committee of the ACUIII at a very reeeut meeting. and dial a revised draft has been prepared. Owing to shortness of inter* veiling dine, this draft has not liccouie available for general distribu tion. However, the Chairman* of the ACUIII Code t'oonoitlee will |iariiei|>ate in a disensaion of this code at a succeeding session of the 11resent meeting of thin l<'oundulion,K Chemical Committee, where there will he ample opimrtiiuity to go into ilclail.s. There is good reason to believe that a uniform industrial hygiene eode flint is adequate, practical, and fnetuul, ami so worded as to take into consideration the various social and economic aspects of the prob lems, should meet with great favor by everyone, especially if adminis tered in a spirit of cooperation willi luunngnnieiit and labor. There are, however, some practical dilllciillies of considerable magnitude to lie overcome, not only in the drafting of a eode of this nature and obtaining reasonable agreement, hut also in effecting its adoption by the sinten, territories, counties, and cities, and the variety of agencies therein, lluit have interest and authority pertaining to industrial hygiene codes. There arc mnuy differences of opinion and questions of alleged fads to he satisfied. Hrief mention of a few of these will follow. Adequacy of Knowledge A fundamental question pertains to the adequacy of knowledge. It is the speaker's opinion, which lie liclicves is shared hv a good many others, that the creation of n uni form industrial hygiene code with the broad coverage that has been attempted is eon fronted with the dilem ma of, on one hand, the need of an adequate, practical code, based un good knowledge and scientific fads; nnd, on the other hand, by inad equacy of knowledge, experience, and facts fur preparing one. Such inadequacies breed variations in eoueepliqii. lack of iiuiiniiuily of opinion, preferences, and prejudices and the like. This is lint a criti cism--it is a state of iilfairs that is believed to have roiiaideralilc responsibility for the variety of codes in existence. It constitutes a real basis fur diflfeuftii*s in preparing a code that is adequate and practical, ami meets the desired slate of definiteness, conciseness, and roinpldcncss. In code making effods. the inadequacies of knowledge are sometimes disposer! of by omission of the os-socialcd requirements. [W] This limy lie the liest procedure. Frequently, however, in flic zeal lo make the code broad in coverage and effectiveness, the procedure of using general statements, iudcflnilcucss of requirements, and delega tion of authority is followed. Rudi procedure may ha acceptable, lo Mime restrained degree, in the interest of having a code available, pro viding reasonable eousideration is given to the existing deficiencies in the administration and the demands fur roin|diuiicc. However, delegation of such authority lo each of the many agencies among the states immediately opens the possibility for differences of opinion, interpretation, and requirements, and provides a very important basis for lion-uniformity of codex--thereby defeating the objective of uni formity. A mere delegation of blanket authority In a eode enforce ment agency for dealing with inadequacies of knowledge, is obviously not it desirable answer to the problem. Element of Opponency Another impediment to the preparation uud adoption of codes and regulations of the type under cousiderutioii, is the element of opponcncV', or even mistrust, that exists lmtwcr.ii arcus of interest, particularly at the present lime iietwccu industry, lubor, and regula tory agencies. It is no secret that, at least occasionally, industrial management believes that government is intent on bedeviling uud encroaching on industrial affiiirx. mid is without concern of indus trial interests; and on the other liiiuil, that government believes that industry needs more and more regulation uud policing. Ax a result, some earnest differences of opinion nrisc. Ouu of tlm criticisms that lias frequently lieeu directed lo the codes of governmental origin, ia the lack of opportunity given for participation by all of the interests, particularly industry, in the code work. Home eodr-timking procedures provide for this participation; others do not. It must lie agreed that an iudiisfriid hygiene eode is of liroud, public interest, and Hint ita formulation should he a joint endeavor and have the lieueflt of tho knowledge, experience, and viewpoints of all concerned. Such coop eration is essential lo the development of good codex, and to their acceptance and use. Code-making procedures should provide it. It cannot lie denied, however, that the leadership in initialing industrial hygiene rode work hits usually arisen in the governmental agencies, and that frequently industry and the other interests have not become concerned until a rode has up|icurcd, and even then their effort has often hern directed more to criticism and obstruction Ilian In ulliiinmen! of good code objectives. There arc many notable except ions, hut in general, industry lias nut fully met its rrximusihililirx for leader ship and eisqaTMtion in creating these eodes. In the main the rclu- I -VI1 lions between industry and tin* governmental indiislriid hygiene facil ities throughout I lie country Iiiim* been good. In general there Iiiih been mi endeavor to lie |ii'ii<'lirnl mid rnliuii;il in establishing mid administering rules and regulations, mid In aid itud assist industry, in providing lienllliy working conditions. Industry respects these facilities mid vulucs the services lliut lire given. '1`liese reliilions kImhiIiI he very helpful in resolving Aliy differences-of upinion on codes mid' regulations if ineehniiiKiini fur cooperative elfort lire provided. In mentioning the uunlel code that is in course of preparation by the A(!(illl. it was pointed out Hint the eoniiuenls mid criticismof industry, lalior, and other interests on the draft had been invited, mid Hint n part of the review had been conducted b.v the American Standards Association. The. plans for the future course of this model code are not known to the speaker, hut it would appear to lie.in keepini' with propriety and practicability to suggest proccssiii# it Ihroiiirli the American Standards Att-sueiatiou. where the participation of all interests could he formally recognized. That association is ualiounl in scope. Its code procedures provide for creating balanced commit tees composed of representation with irisid specialized knowledge for dealing with a particular subject, from all interests--labor, industry, mid the public. American Standards Association (lodes represent a consensus of good knowledge and good American practice. It is believed that the issuance of uu industrial hygiene code under this. Association's procedure, with a combined represent a I ion of all. inter ests, would greatly assist in .obtaining national recognition and apn proval. One way of selling an idea to a prospective customer is to share the idea. That procedure not only helps to sell the idea, hut at the same lime removes its faults. Type, Scope, and Conlenl of Codes The type, scope, and content of industrial hygiene codes are sub jects mi which there is honest and sound disagreement nmdiig and lielween Imlli regulatory and non-regidutory interests, from several viewpoints. A basie ipiestiim pertains to whether eodes should lie specialized, such as aperitif industry, trade, is'enpatiiiii or product codes, or whether they should lie general, all-iuelusive, all-industry elides. Itotli pruetiecs are in use, both have advantages mid disadvan tages, hut either one would lie satisfactory if well developed mid administered. The next question pertains to coverage within a par-' lieiilnr type of emle, it having been previously sluled that the present* coverage of codes ranges from little more than general sanitation, to! moderately complete coverage of environment. I| is lielicved that enverage should lie complete to the extent that valid infiii'iiiathiii is [S4], available for defining the requirements. A third question pertains to whether the scope slinll Ik* confined to the rather general present con cept of duties of industrial hygienists in cfTceting control of environ mental factors that are directly related to licallli as commonly inter preted, nr whether it shall include subjects of safely and health and medical services that areeiiiuumnly recognized lobe within the purview mid province of industrial safety and industrial medicine. The prnposed model A(`(illl code previously referred to follows the latter pat tern to some extent, h'or a Ijing lime the speaker has had a conviction that insofar ns harmful agents of industrial environment are con cerned. the knowledge, skills, procedures, and teamwork that is re quired to eoiitrol the agents and protect workers are too similar, over lapping, Hint interdependent to segregate industrial health, industrial hygiene, and industrial safety into three distinct services or jurisdic tions. Attempts to do this are not only dilllciill hut also rather unreal. However, lids viewpoint of broad scope and content of eodes mny lie tun idealistic for wide nceeplituee at (lie present lime, owing In exist ing practices of industrial organization mid ndiuiiiislralioii of depart ments of medicine, hygiene, and safety. M Some Agreement on Scope The diirereuees of opinion relating to type and scope of industrial hygiene eodes will lie difficult to harmonize, at least in the near future, liecuusc there is more than one good nuswer to many of the questions. Perhaps the way will he open to more progress if attention would lie given to relative importance of some of the questions. The speaker lias previously indicated his opinion that either type of code, specific, nr nil-industry, would serve Hie pur|M>sc if well developed and well administered. Of mure importance is n practical ihTuiitimi of scope nr ill least some agreement uu snipe among Imlli the interests and the professions that are involved in carrying uut the provisions of a emle. Adequate representation of all interests should lie a part of liny codcniakiog body. When industrial hygiene codes transgress to n signillcant extent into fields of safely and medicine lliey should hear a title Hint is indicative of their aeope. The most urgent present need is. Hud regardless of variation in scope and coverage among codes. Ihe definition of good practices and requirements should, to the extent that lliey are included in eodes. Is* more uniform Hum now prevails among Hie codes in Ibis country. Il is rather generally agreed tlml a qiianlilalivc definition of hygienic environment in terms of required qualities mid harmful chemical, physical, and biological agents, is a very essential purl of an industrial hygiene code. Such definition is a statement of an objec tive which, if itlluiucd, will provide the desired result of healthy work- ini' conditions. Further, it provides n mcusure tintI is nccessury for the i-rcaliou of kuc.Ii conditions through the <losi|ri of structures, equipment, mill working surroundings, oml I In* maintenance thereof. However, I lie endeavor to iletine hygienic environment Inis been one of the most important sources of disagreement mol iliniculty in the preparation of industrial hygiene rudes. Disagreement on Terminology and Definition The points of disagreement and the problems to he resolved arise from ninny sources ami arena of consideration. They inelinlc the existence of terminology with misleading coiumtnlioii, differences of roiirc|it, deficiency of knowledge in muny areas for i|nnntitotirc (lelinilion. misinterpretation of inforinatioii, mol ronferenee of un warranted or ujustified reliability to alleged fuets mol ilnta. A few of tilese will lie discussed rather briefly. The eoninioiily lined terminology, "maximum allowable eoneeo- t rut ion, " "maximum perntinxible concentration," "toxic limit," and llo> like, for designating standards of hygiene arc unfortunate ox true- lions from phrases originally used to luliel ei|ierimentul data, espe cially that pertaining to a maximum dosage in relation to an acute physiological or pathological response. These phrases connote a rather precise <|uaulitatiou and association of environment with toxic muni- feat at iotiN. In becoming rather synonymous with slumlords of environ ment they convey to many persona an understanding that such stand ards are also rather precise critical vulues just bclmv which a person is safe and above which lie will lie injured--or a condition which a iiiuii can tolerate blit beyond which lie is immediately in danger. Such a concept of a hygienic standard is unsound, liven though u fair degree of precision might be established for a small group of individ uals under a specified controlled condition of contact, the precision of niicIi homogeneous data would, in most instances, be lost immedi ately when applied to the heterogeneous nature of both industrial environment and the response of individuulH of a group of workmen to the environment. The foregoing is nut a condemnation of (he use of toxicological data ns an element of important consideration in deriving acceptable standards of environment. Such knowledge is a necessity for avoiding the area of danger. The purpose of the discus sion is tu |mint out the desirability of disassociating the idea of maxi mum tolerable stress from tin* euuecpt of hygienic standards and to adopt the ridiouiile of including fiii'lurs of safety and good practice. N'o engineer would think of using the near failure limits of materials in designing a structure. ' Another viewpoint that is receiving increasing nlleiilioii in dellu- ing acceptable standards of environment, is (hat of more ronsideriilioif t v, 1 of comfort. In partieiilar. Ibis pertains In sensory elfects of transient and. on the luixis of present knowledge, harmless manifestation* kiicIi a* slight irritation of the eyes nr nose, nauseating odors, mnl mild degrees of uurcotic cITeels; also, to couilitious stteli us imcomforlnhlc temperature mnl excessive nimiiuitH of nuisance dusts. . A question that is fnspiently asked regarding the extended lists of M.A.that are included nr suggested for inclusion lit codes is: Arc these "limits" reliable enough to be written into industrial hy giene codes as mandatory requirementsf In the state codes that have been developed, the limits are mandatory in about half of I hem mid suggested hygienic standards in the remainder. It is the speaker's opinion I lint there is adeipiale. knowledge for deriving a reliable alandaid for relatively few substances. There is also some useful knowl edge pertaining to must of the substances nucoimtcreil in industry and appearing in current lists of standards. This knowledge is in general not believed to be adctpialc for n determination of standards 1 lint have the reliability mid validity that mandatory requirements should possess. They should be considered to be tentative working guides pending the availability of better information, Fur this pur pose they.are useful if consideration is givrn to their liuiltutinuH. It is believed (but this opinion is shared by tuxicohigisls that have acquaintance with the situation; also, l>y some of the pertains that are responsible for compilation of such lists. Allowable Exposure Limits In the past the endeavor has been, with few exceptions, to select u single "limit," "einiceiitratimi" or "tolerance level" for defining tin* permitted exposure fur a working dnv of eight hours. There has also been a rather general tinderalmidiug among moat persons that siifh definition was applicable to nil other cnndilinua of environment and occupational activity. It has been mentioned previously Unit industrial,atmospheres nro rarely homogeneous, with llm result that in must siluiitious the ex (mstire levels during a day vary rousidcridity for u numlier of praeticul reasons. This creates a very important difficulty in attempting tu appraise industrial exposures in terms of a simple, single standard of hygiene. In meeting llm problem, the general industrial hygiene practice varies from making a few s|mradic determinations (which may Im worthless or even vicious) to more extended systematic investigations, with result* represented either by simple averages nr by an integration of the time mid concentration of exposure eyries. These procedures, especially that of irilcgruliog the time am) concent ration, may lie a practical expedient, hut even llm latter may result in erroneous appraisal of either llm harmless or harmful nature of the environment. For several reasons, loxicologi- ' [S7] I cm I response cniiuot be expected to be u lineur function of lime mul concentration. The ainplitnile And frequency of variation from a defined menu inny be very important. Many other eheinieid, physical, and perhaps even biological agents or factors of environment--even variation in chemical iiaturoor physical form of the kuiiic.substance-- may have n very significant influence on the physiological or patho logical response to n specified amount of one agent, and even on (another with which it ia associated. In some instances the inllnmee may he synergistic and in others antagonistic. Although time docs not permit uu extended discussion of toxicology, it is pertinent to the question of industrial hygiene standards to mention a few1 examples of these iullucuees. The iniuute-\`olume of air inspired and of blood circulated through the lungs increase rapidly with physical activity. For strenuous work the volume of air may be or the order of III or more and blood circulated 5 limes that for sedentary activity. The amount of most harmful airborne contaminants that are acquired through the lungs from a particular environment and its trausporlalion into the body may vary in the same general order. For these reasons a "maximum allowable concentration'' may readily hqve a large safety factor for one degree of activity or a large factor of , "unsafely" for another, dlot environment also increases respiration /' and circulation. Increased pressure of atmospheric environment, such ( ns experienced in compressed air work, increases the mass of a harm ful gas in unit volume of air and can be generally expected to increase the effectiveness concentration of the environment as compared to the same air-contaminant proportions at "imrmul" pressures, exceptions being those in which an antagonistic agent is likewise effectively conccnlrulcd. Such increase in potency may be expected owing not only Ito I lit* fact that the mass of agent is directly increased, but owing also to non linearity of response with concentration. I;itlle is known about the variation in response with particle size of dispersoids--their retention in the lungs, their solubility, and other elements of physi cal, chemical, and biological behavior (lint are associated with size and surface. However, enough is known to give a basis for expecting con siderable differences. The foregoing pertuiun to the reintimi of only a few specific agents and factors. The situation becomes very rmnplex when all fnelors ore considered. It requires that more attention he given to ull important agents and factors of industrial environment ami occupational activity in the development and list* of standards; it supports the necessity of including an ample factor of safety in slandarda; it suggests the |masihlr usefulness of multiple standards; mul it emphasizes an existing inadequacy of knowledge und the need of an expanded progruin of research. irnforlnnalely this need greatly exceeds the facilities that are avadahlc for supplying it. i [ iW ] Procedures for Solving Problems - A procedure that offers good |Missib'dities for resolving some of the problems arising from limited knowledge is to define industrial hygiene standards for atmospheric agents in terms of an established system of zones; Mich as (fur illustration onlyl Zone I. 0-H ppm; Zone 2, -1-1(1 ppm; Zone il. 1II-5MI ppiu, etc. A portrayal Mini use of Ihc presenl knowledge in this manner would not only give recognition tu the limilalious of knowledge hut also to the dillh-ntly of accurately assessing the environment In which A standard is In lie applied. II would avoid the multitude of individual numbers and hair-line deri sions that industrial hygienists must deal with at the present time. A very important feature would he the possibilities for harmonizing differences of opinion on standards for particular sultstniucs ami nhlamiiig more uniformity among code-making ngem-ica. It is appar ent that the development of an acceptable schedule of zones will require considerable study, and that some later modilieatioii may he necessary to meet individual substances and new knowledge. Also that there will he some cnuliuunucc of differences of opinion relating to zone assignments. However, the inherent good jmssihilitics for mitigating some of Ihc present problems, invites real attention with open-minded considerations. A procedure of Ibis kind wns discussed liv the American Nlnndurds (hnumiUec on Allowable (,`ouccnl rat inns of Toxic Dusts and (fuses, Zff7, al its meeting on December it, l!47, and subsequently published by Drinker and (iook.* ANA Committee ZH7 is continuing to explore the possibilities with a view tu the devel opment of a schedule of zones. Nome of the other comments lliut are pertinent to many of lint lists of limits may Is* mentioned, hrielly. The llrsl of these Inis been discussed, namely, the lidx-liug of the limits as "maximum allowable" or "maximum permissible," or the like. Another is (tic mixture of emu-epts represented hy the limits; in some it is Hint of maximum lolerahle, in others it is a sound concept of hygienic standards. A real delieieiu-y is failure to designate whether the deluiilion is related to taxieologieal effects or to sensory effects--to niuintcnuiu-n of good health or comfort, lu many iusluurc* the origin of the limit is obscure and validity is diflicull to assess. However, notwithstanding their drlleieneiea and limitations, these limits appear to be gaining in prestige and Authority through mere copying and repetition. It should be realized Ihnl repetition docs not improve validity. Again, litis is not A eundcuundiou of the use of such information ns guides (even (hough recognized as Is-ing inadequatel, if it represents the lu*st information ami is*used with consideration of its limitations. . A very broad basic question rclntiiii; to specific mandatory ifquirritieitls of any nature, is Unit of desirability, even though reliable. Mandatory requirements are usually minimum requirements, or repre sentative of the worst permissible cmiilitiuiiK. From one vieu`|miiit aucli requirements are a necessary aid to code administration for deal ing with rcealcitruuls; from another viewpoint, they tend to slide progress and freeze endeavor at the established minimum. Determination of Compliance with Environmental Standards I'roecduru for a reliable determination of compliance with the requirement of a eodc is an essential component of the requirement. Frequently the numerieal value is a product of a specific technique. An understanding of the necessary technique should always be pro vided by text or by reference. The mere choosing of a sample or scries of samples that will reliably represent the air hrcHthed by workmen and provide a quantitative result that cun he integrated with a stand ard of hygiene is not only difficult, hut at best involves much uncer tainty. A few inches variation in position or time in production cycle, or from day to day, scusou to scumoii, or other fads may change the composition many fold. Hath theoretically and practically, a sample of air can be relied on to represent only the air that existed at I lie exact point of sampling at the lime the sample wus tuken, and Die same condition may never again occur, i This situation can ha the cause of large error in the conclusions drawn from investigations made fur determining compliance with code requirements, or for quantitating the agent that is responsible for the occurrence of ill liealth arising out of industrial exposure. The conditions that were responsible for the episode may differ greatly from those found at Nome previous or subsequent time. Since standards or changes in standards arc often based on such investigations, the possible lack of reliability is very sppureot. Although major attention is usually given lo precision and accuracy of methods of determination, the real IHiNsibilitics of error ore inherent in obtaining n sample or a physical observation that represents the exposure. * Some Problems Relating to Adoption of a Uniform Code There are some knotty problems to be solved in an endeavor to obtain wide acceptance, of any kind of uniform code pructicc among the stales and agencies wilbin a slate. Much luinimnmug of view points and integration with existing codes and code administration will be necessary. Nearly all of llm si ales huve two or more separate agencies with code prerogatives that arc related lo matters of hcultli and safety. The reluctance of such agencies to relinquish authority (] ha* been demons!rated repeatedly. Tbe problems that are presented will probably W more difficult to solve than those of developing an acceptable form of code. An approach to (lie problems might well be for Hie several agencies within it stale to first endeavor to eliminate existing dilfercucrs in R|tccific requirements of their codes and then agree upon a single administrator for all items relating to industrial hygiene. Agreement among the many states presents a more difficult problem. Tin* existence of states' rights, with op|mrluuity for inde pendent thought and net imp remains potent in many areas. Summary In this discussion there has been an cudcuvcr to deal, ml her generally mid briclly. willi some of the objectives of industrial hygiene codes, their desirable features, particularly those |ierlaiuiug to more uniformity of practice. Attention bus been given lo some of the defi ciencies of present codes ami to some of the ulistaclea to tbe develop ment and use of belter codes. Tbe treatment of these subjects is not only inadequate, but many other pertinent ones have necessarily been ..nutted from Ibis relatively short discussion. A general appraisal of the code .situation as portrayed may create sonic doubt ns to whether any of tin* existing codes lire very useful, or if an adequate uuifnnii code can lie developed. That is not a proper inference or conclusion. The broad underlying thesis that an attempt has Wen iiiudc to con tribute, is that of encouraging endeavor to improve codes from the over-all viewpoints of validity, adequacy, and practicability. Where critical. Hie endeavor lots Wen either that of re orienting thought or to imiuiing out areas fur improvement. Many of the problems have real elements of difficulty, but are amenable to solution through Hie good faith and coopcrution of ail concerned, supplemented with inves tigation and research for improving knowledge mid removing areas of deficiency. II is Wlicvcd that most of llio problems and difficulties arise out of a lack of knowledge for preparing a broad homogeneous definition for nu indefinite heterogeneous situation. ItKFiiKKXOH.S I. Crecnburg, Wonard: Procedure in the Formulation nml Adoption of Codes of Industrial llyglunc. begat Conference, I.ItIt Annual Meeting of the Industrial Hygiene Foundation (November t7, HUH). 1 Bloomfield, J. J.: Codes for the Prevention und Control of Occupational Diseases. Ilth Annual Meeting of the Industrial Hygiene Foundation (November 7, IV10). 3. YatTe, C. I).: Proposed Uniform Industrial Hygiene Code. Chemists' Conference, 13th Annual Meeting of the Industrial Hygiene Foundation (NovemWr IV, 1048). 4. Drinker, Philip, and Cook, Warren A.: Masimtim Allowable Concenliu* Hun* of Atmospheric Impurities. Jour. Iiid. Ilyg. mid Tos., 31. p. lit, (January 104V). ^^