Document ZbJmjxZYN4MEqkDmOBJr8RQ8

FILE NAME: Union Carbide (UC) DATE: 1956 Sept DOC#: UC338 DOCUMENT DESCRIPTION: Industrial Hygiene Quarterly - Prepared Discussion Henry F. Smyth, Jr. V! ' CURR. f j AMERICAN -oS2 cL CO E TC3 03 ED. LIT." T Y has stood for tly larger particles -omen in the plant with which PAX soils. ill the dirt, grim ng! Less time spent in additional over s results -- fast -- oil, grease, grim) deeply ground in.. Industrial H y glene ASSOCIATION Quarterly VATERLESS SKIN SER witU tke PAXI VOLUME 17. NUMBER 3 SEPTEMBER. 1956 Q1ENE AMERICAN INDUSTRIAL HY ASSOCIATION liately ing lied by a Volume 17 SEPTEMBER, 1956 Number 3 er with in vivaient Symposium on T hreshold L im its Present Trends in MAC'S ......................................................... Warren A. Cook o O The Need for Threshold Lim its........................................ Miriam Sachs, M.D. <D Prepared Discussion........................................................... Henry F. Smyth, Jr. 'ill have rial ;hemical sound irity Methods of Establishing Threshold Limits................... James H. Sterner, M.D. Prepared Discussion..............................................Herbert E. Stokinger, Ph.D. Engineering and Chemical Application of Standards ... .Allen D. Brandt, Sc.D. Prepared Discussion................................................................ Arthur C. Stern Prepared Discussion ............................................. Theodore C. Waters, LL.B. A utomatic I n strum entation for A ir P ollution Monitoring-- A P rogress & R eport on A uto m a tic Dir ec t io n a l A ir Sa m p l i n g .................William A. Munroe 298 f lesign, >f ;ontrol of tion. A V ersa tile P ortable A ir Sa m p l e r ..........................H .S . Jordan and R. N. Mitchell 303 Determ in a tio n of I n tern a lly Deposited R adioactive I sotopes from E xcretion A n a l y s e s ............................................................... Wright H. Langham Criteria for a n E valuation o f N o ise P r o b l e m s ....... Charles R. Williams, Ph.D. F lo w Calibra tio n o f H ig h -V o lu m e S a m ple r s ..................................................................... Bernard D. Tebbens, Sc.D., and Donald M. Iieagy, M.S. 327 R ecent I ndustrial H ygiene Developm ents-- A Symposium In the Field of Air Pollution......................................................Henry N. Doyle In the Field of Chemistry..............................................Ralph G. Smith, Ph.D. In the Field of Engineering...........................................Leslie Silverman, Sc.D. In the Field of Noise.................................................................. Vaughn H. Hill In the Field of Radiation.............................................................Saul J. Harris In the Field of Toxicology...................................Herbert E. Stokinger, Ph.D. H y g ie n ic guide ser ies .......................................................................................................................... P r esid en t's page .................................................................................................................................... Selected T it l e s and A b s t r a c t s ..................................................................................................... B ook R ev iew ................................................................................................ ............................................ A I H A I n d u str ia l A sso cia tes, O f f ic e r s , D irectors, a n d Co m m i t t e e s ...................... 'ing Inc.fiem !sfry| ware American I ndustrial H ygiene Association Quarterly, published by the American Industrial Hygiene As sociation in March, June, September, and December. H oward N. S chui.s . Editor; H erbert J . W eber. Advisory Editor; L loyd E. Gordon, Associate Editor; W illiam S. J o h n so n , Advertising Editor; P au l D.' H alley, Cir culation Editor; A . D . Cloud, Publisher; D obis F lournoy, Editorial Assistant. Publication and Editorial O f fices. G06 North Michigan Avenue. Chicago 11, Illinois. Subscription *4.00 per year in the United States: $4.60 per year in Canada; $6.00 per year in other countries. Single copies, $1.60--except the June, 1966, issue which is $2.00. Copyright, 1956, the A merican I ndustrial H yoiene A ssociation. Entered as second class m at ter May 3, 1948, at the post office a t Sheboygan, Wisconsin, under the Act of March 3, 1879. The A merican Industrial H yoiene A ssociation Quarterly reserves the right to edit all advertisements and to refuse advertis ing copy when it does not meet the high professional standards adopted by the Association. ber, 1956 ng of 260 we to be .cent with roentgens me week? ne within ve should larily be se the exunnecesworking below the ined with expense, w a pracrved--not ssing the er limits Even the some efen if the ' the in ult from prevent j should etectable ninate it the im practice. ate, and aly as a ever has 11permit nan haz- human In d u stria i !e C oncenn an ts. Jfl- xim um AlFebruary, mum Per- ^erm issible Radiation 1955. I Industrial Hygiene Quarterly 279 ' . Prepared Discussion which is recorded in some of the threshold limit values. Whether we want him to or Dt HENRY F.lSM YTH, JR. not, he ( and that includes every one of us at ' Mellon Institute times) will use threshold limits as estimates of comparative toxicity to meet his urgent Pittsburgh requirement for finding some basis for opin ion. r . s a c h s has established that the vast To what extent is he wrong? A threshold majority of our colleagues recognize limit based on comfort, irritation or good their need for a list of threshold limits. Sheengineering practices certainly is not com distinguishes between the need of the official parable to one based on pathological effect. agencies for a screening device to apply to But the former limit is certainly lower than thousands of industrial processes they en one based on injury. The error is on the side counter in field work, and the need of the of safety if it is stated that material A has private industrial hygienist for an engineer a threshold limit based on comfort higher ing bench mark for planning and evaluating than that of material B which is based on environmental control. To satisfy each of injury, therefore material A should be used these needs vapor concentrations must be in the process. measured under operating conditions before No matter which material is chosen it the threshold limits values can be useful. will be employed, by persons subjected to the There is a third group which uses thresh same degree of industrial hygiene and medi old limits and needs them because nothing cal scrutiny. By choosing the material with better suited to the need is available. Every the higher threshold limit the probability of one of our profession is a part-time member safe operation has been increased, even if of this group and some are full-time mem the basis on which the choice was made is bers. Reference is made to the arm-chair in not numerically sound. dustrial hygienist. He may never measure a There is one "important short-coming in concentration and he may never observe an this argument which points out an im industrial operation. He uses threshold lim portant way in which threshold limits do not its to advise upon the selection of a chemical meet the needs of the arm-chair industrial for a particular application, to select a suit hygienist. If the volatility of a material with able application for a little known chemical a high threshold limit is greater than that and to bolster sales arguments for a chemi of a material with a low limit, then in a cal or mixture of chemicals. particular process the less toxic material When the industrial hygienist is asked to may be more hazardous, because a greater advise whether acetone, propyl acetate, or vapor concentration will be in the atmos methylene chloride would be the safest sol phere. vent in a particular application, it may be I maintain that the list of threshold lim believed that his answer is based on a pro its is our best available source for judg found knowledge of toxicology, but actually ments on comparative toxicity of vapors to he recalls the threshold limits, or refreshes humans. It can be improved for this pur his memory by consulting the list while the pose, but there is nothing better for us to questioner waits on the telephone. Then the use. However, it refers to toxicity, not to answer is given as if the list recorded com hazard. It is the single-phased toxicity of K. parative toxicities, perhaps adding a bit of B. Lehmann. A table of comparative hazards qualitative information on fire hazard and would go back to Lehmann's two-phased type of injury from an excess. toxicity by combining vapor pressure (or What better data are available for the evaporation rate) with toxicity. This table arm-chair industrial hygienist than the an of comparative hazards is what the arm nual list of threshold limits ? He must have chair industrial hygienist really needs. It some guidance if he is to do more than toss a would go a long way toward satisfying all coin. If he is given a list based on uniformly of his needs, particularly if it included in conducted animal experiment, he is deprived formation on nature of injury, on the penal of the benefit of the years of carefully ob ty for exceeding the limit and on the degree served and evaluated ' human experience of hygienic urgency for observing the limit. The material on this page was copied from the collection of the National Library of Medicine by a third party and may be protected by U.S. Copyright law.