Document BR9gvv07BQVKmNnDd4pyDqoXj

* Threshold Limit Values For 1964 ,i Adopted at the 26th Annual Moating of the American Conference of Governmental Indus trial Hygienists, Philadelphia, Pennsylvania, April 25 - 28, 1964 01 023 0665 Copyright 1964. by American Conference of Governmental Industrial Hygienists. The American Conference of Governmental Industrial Hygienists will welcome requests tor permission to republish or reprint these Threshold Limit Values. Requests for such permission should be directed to the Secretary-Treasurer. 1014 Broad way. Cincinnati 2. Ohio. Reprints may be purchased from the SecretaryTreasurer 1014 Broadway. Cincinnati 2. Ohio. THRESHOLD LIMIT VALUES FOR 1964 Adopttd of the 26th Annual Meeting of the American Conference of Governmental industrial Hygienists Philadelphia, Pa., April 25*28. 196-1 The threshold limit values refer to air-borne con centrations of substances and represent conditions under which it is believed that nearly all workers may be repeatedly exposed, day after day. without adverse effect. Because of wide variation m individual sus ceptibility, exposure of an occasional individual at or even below the threshold limit may not prevent dis comfort. aggravation of a pre-existing condition, or occupational illness. Threshold limits should be used as guides in the control of health hazards and should not be regarded as fine lines between safe and dangerous concen trations. Exceptions are the substances given in Appendix A and certain of the substances given a "C" listing. The values not given a "C" listing re fer to time-weighted average concentrations for a normal workday. The amount by which these concen trations may be exceeded for short periods without injury to health depends upon a number of factors such as the nature of the contaminant, whether very high concentrations even for short periods produce acute poisoning, whether the effects are cumulative, the frequency with which high concentrations occur, and' the duration of such periods. All must be taken into consideration in arriving at a decision as to whether a hazardous situation exists. Enlightened industrial hygiene practice inclines toward controlling exposures below the limit rather than maintenance at the limit. Threshold limits are based on the best available information from industrial experience, from experi mental human and animal studies, and when possible, from a combination of the three. The basis on which the values are established may differ from substance to substance: protection against impairment of health i 01 023 0666 r may be the guiding factor for some, whereas reason- able freedom from irritation, narcosis, nuisance of other forms of stress may dominate the basis for others. The Committee holds to the opinion that limits based on physical irritation should be considered no less binding than those based on physical impair ment: growing bodies of evidence indicate that physi cal irritation may promote and accelerate physical impairment. On what basis a limit is developed is given separately for each listed substance in "Docu mentation of Threshold Limit Values." a publication of the Threshold Limits Committee of the ACGIH. Ceiline vs Time-Wetchted Average Limits, AJthougn the time-weighted average concentration pro vides the most satisfactory, practical way of moni toring ait-borne agents for compliance with the limits, there are certain substances for which it is inap propriate. In the latter group are substances which are predominantly fast acting and whose threshold limit is more appropiately based on this particular response. Substances with this type of response are best controlled by a ceiling "C" limit that should not be exceeded. It is implicit in these definitions that the manner of sampling to determine compliance with the limits for each group must differ; a single grab- sample, that is applicable to a "C" limit, is not appropriate to the time-weighted limit; here, a sufficient number of samples are needed to permit a time-weighted average concentration throughout a a complete cycle of operations or throughout the work shift Whereas the ceiling limit places a definite bound ary which concentrations should not be permitted to exceed, the time-weighted average limit requires an explicit limit to the excursions that are permissible above the listed value. The magnitude of these ex cursions may be pegged to the magnitude of the thres hold limit by an appropriate factor shown in Appendix C. It should be noted that the same factors are used by the Committee in making a judgment whether to include or exclude a substance for a "C" listing. "Skin" Notation. Listed substances followed by the oesignation "Skin" refer to the potential con- 2 tnbution to the over-all exposure by the cutaneous route including mucous membranes and eye. This attention-calling designation is intended to suggest appropriate measures tor the prevention ol cutaneous absorption so that the threshold limit is not in validated. Mixtures. Special consideration should be given also to the application of these values in assessing the health hazards which may be associated with ex posure to mixtures of two or more substances. A brief discussion of basic considerations involved m de veloping threshold limit values for mixtures, and methods for their development, amplified by specific examples are given in Appendix 8. ``Inert" or Nuisance Particulates. A number of dusts or particulates that occur in the working en vironment ordinarily produce no specific effects upon prolonged inhalation. Some insoluble substances are classed as inert (e.g. iron and steel dusts, cement, bentonite, silicon carbiue. titanium dioxide, cel lulose); others may be soluble (starch, soluble oils, calcium carbonate) but are of such a low order of activity that in concentrations ordinarily encountered do not cause physiologic impairment: still others may be rapidly eliminated or destroyed by the body (veg etable oils, glycerine, sucrose). In the case of the insoluble substances, there may be some accumula tion in the respiratory passages. In the case of the soluble substances, this accumulation will ordinar ily be temporary but may interfere to some extent with, respiratory processes. Hence, it is desirable to cdntrol the concentrations of such particulates in the air breathed by any individual, in keeping with good industrial hygiene practice. , A threshold limit of 15mg/m , or 50 mppcf. which ever is less, is recommended for substances in these categories and for which no specific threshold limits have been assigned. This limit, tor a normal work day, does not applyto brief exposures at higher concentrations. Neither does it apply to those substances which may cause physiologic impairment at lower concentrations but for which a threshold limit has not yet been adonted. Physical Factors. It is recognized that such phy sical factors as heat, ultraviolet and ionizing radia- 3 [ 01 023 0667 i-- jg K non. humidity, abnormal pressure and the like may place added stress on the body so that the effects from exposure at a threshold limit may be altered. Most of these stresses act adversely to increase the the toxic response of a substance. Although most threshold limits have built-in safely factors to guard against adverse effects of moderate deviations from normal environments, the safety factors of most substances are not of such a magnitude as to take care of gross deviations. For example, continuous work at temperatures above 90*F or over-time, ex tending the work-week more than 50%. might be considered gross deviations. In such instances judg ment must be exercised in the proper adjustments pi the threshold limit values. These limits are intended for use in the field at industrial hygiene and should be interpreted and applied only by persons trained in this field. They are not intended for use. or for modification for use. i It as a relative index of toxicity, by making a ratio of two limits. (2) in the evaluation or control of community air pollution or air pollution nuisances. (3) in estimating the toxic ootential of continuous uninterrupted exposures. (4) as proof or disproof of an existing Disease of physical condition, or (5) for carte blanche adoption by foreign countries. These values are reviewed annually by the Com mittee on Threshold Limits for revisions or additions, as further information becomes available. "Notice of Intent" At the beginning of each year, proposed actions of the Committee for the forth coming year are issued in the form of a "Notice of Intent." This Notice provides not only an oppor tunity for comment, but solicits suggestions of sub stances to be added to the list The suggestions should be accompanied by substantiating evidence. Legislative Action The Conference does not consider the Threshold Limit Values appropriate matter for adoption in legislative codes and regula tions. and recommends against such use. Reprint Permission. This publication may be re- prmteo provided that written permission is obtained from the Secretary-Treasurer of the Conference and that it be published in its entirety. 4 RECOMMENDED VALUES (In Alphabetical Order) Swbstpnc* ppm* Up k**' Aceuideiiyde............................. 200 Acetic acid.................................. 10 Acetic anhydride........................ 5 Acetone........................................ 1.000 Acetonitrile................................ 40 Acetylene reuabiomide............... 1 Actateta...................................... 0.1 Acrylonitrile - Skin.................... 20 Atdtin (l. 2. 3, 4, 10. 10- heieeMoro- 1, 4, 4a, 5, 8. 8 a-hexanydto-l. 4, 5. 8-di methano-naphthalene) Skin ... Allyl aiconoi Skin..................... 2 Ally! chlotide.............................. 1 C Allyl (lycidyl ether (AGE)......... 10 Allyl propyl disutride................. 2 Ammonia .................................... 50 Ammonium sulfamate (Ammate).. Amyl acetate.............................. 100 Amyl alcohol (isoamyl alcohol). 100 Aniline - Skin.............................. 5 Antimony A compounds las SO) ANTU (alpha naphthyl thioutaa).................................. Arsenic A Compounds (as Asl - Atsine.......................................... 0.05 Barium (soluble compounds)..... C Benzene (benzol) - Skin........... 25 Benzidine.................................... Benzyl chloride.......................... 1 Betylltum.................................... Boton oxide............................ - 360 25 20 2.400 70 14 0.25 45 0.25 5 3 45 12 35 15 525 360 19 0.5 0.3 0.5 0.2 0.5 80 Ai 5 0.002 is a urn ' C roiltwew iwil pr HO mm. Hg entwri VWMWWB AMrotimott milligrams of torttcutsto p*t ctabtt motor ol * HomOovs. Sot laaiMii a 5 1 023 0668 Swbstonc* ppm* C Boion trifluonde........................ i Bromine........................................ 0.1 Butadiene (1, 3-butadiene>....... 1.000 2-Butanone imethyl ethyl ketone|.................................... 200 2-Butoxy ethanol (Butyl Cellnsclvei Skin.................. SO Butyl acetate in-dutyl acetate!. 200 Butyl alcohol.............................. 100 tert. Butyl alcohol................... 100 C Butylamme.................................. 5 C tert. Butyl chromate las CrOa) - Skin ..................................... - n- Butyl glycidyl ether (BGE).... SO Butyl mercaotan.......................... 10 p-tert. Butyltoiuene.................. 10 Cadmium onde fume................... - Calcium arsenate ............ - Camphor ..................................... - Carbon dionde............................ 5,000 Carbon disulfide Skin.............. 20 Carbon monoxide........................ 100 Carbon tetrachloride Skin...... 10 Chloidane (l, 2. 4, S, 6, 7, 8, S-octacnloro-3a. 4. 7, 7a. tetrjnydro-4, 7-methanoin- danel .................................. - Chlorinated camphene, 60f...... - Ch lot mated diphenyl oxide...... - Chlorine..................................... 1 Chlorine dioxide........................ 0.1 C Chlorine tiifluoride.................... 0.1 C Chtoroacetatdehyde.................... 1 Chiotooeniene (monochlorobenzene).................. 75 Chlorobromomethane.................. 200 Chloiodiphenyl |42* chlorine) Skin- Chlorodipnenyl (S44> chlorine) Skin- C Chloroloim (tricnloiomethane)... SO l-Chloio-l-nittapiopane............ 20 Chlordbicrin............................... 0.1 Chloioprene (2-cnloio-l, 3-butadiene) .... 25 3 0.7 2,200 590 240 950 300 300, 151 0.1 270 35 60 0.1 1 2 9,000 60 110 65 0.5 0.5 o.s 3 0.3 0.4 3 350 1,050 1 0.5 240 100 0.7 90 6 1 Swbtionc* OP** Mp M* Chromic acid ano chromates (asCiOs) ....... Cobalt......................................... - Crag (R) herbicide __sodium 2-(2,4- dichloiophenoxy) ethanol hydrogen sulfate . . Cresol tall isomeis) Skin........ Cyanide (as CN) - Skin............... 5 - Cyclohexane............................... 400 Cyclohexanol.............................. 50 Cyclohexanone........................... 50 Cyclohexene............................... 400 2,4*0 <2,4-dichtoiophenoxy acetic acid)............... - DDT ~2.2-bis (p-chlorophenyl) - 1.1,1-tiichloioethane Skin - DDVP (0. O-Dimethyl-2,2-dichtoio- vinyl phosphate) ................. Decaborane Skin..................... 0.05 Diacetone alcohol (4-hydroxy 4-niethyl-2-pentanone).. 50 Diboiane ..................................... 0.1 1,2-Dibromoethane lethylene dibromidel.............................. 25 o-Oichlorebenzene.................... 50 p-Oichlorobenzcnc..................... 75 Oichlorodifluoromethane............ .1,000 1.1-Oiehloroethane................... . 100 1.2-Oichloroethane (ethylene dicnioiide)............ 50 1,2-Dichloroethylene................ 200 ) Oichloioethyl ether.................... 15 Dichloiomonofluoiomethane..... 1.000 11,1-Otchloto-l-niooethane........ 10 Dichlorotetrafluofoethane.......... .1.000 Dieldrm (1,2,3,4,10,10-hexaehloro -6,7-epoxyl, 4, 4a, 5,6.7,8.8a- octahydio-1, 4, 5,8-dimethano naphthalene) Skin.............. Diethylamide............................ 25 0. 0.! 15 22 5 1.400 200 200 1,350 10 1 1 0. 240 0. 190 300 450 4,950 400 200 790 90 4,200 60 7,000 0. 75 +1964 Addition or dotation ot " C" t1964 Rovition - mo Tontotivo Votooa 7 L oi 023 0669 rSwbt<ttA ee<* i Difluorodibtomemethane............. 100 C Oiglyctdyl ether (DGE)............... O.S OiisoDutyl ketone....................... SO Dimethyl acetamide Skin......... Oimethylaniiine (N-dimethylaniline) Skin.................. _........ t Oimethyltormamide Skin........... 10 s - 1,1-Oimethylhydrazine Skin .... Oimethylsulfate - Skin ............... 0.5 1 Dinitrobenzene Skin................. Oinitrottluene Skin........ ......... Dinitroresol - Skin............... - - Dioxane (diethylene dioxide)..... 100 Oipropylene glycol methyl ether Skin.............................. 100 Endrin (1,2,3,4,10,10- hexa- chlorp-6. 7-epoxy 1,4,4a, 5,6,7.8 8a-octanydro 1,4-endo-5, 8-dimetoanonaphthalene) - Skin.. - EPN (O-ethyl O-p-nitropnenyl thionobenzenephosphonate) Skin Ethyl acetate....... ....................... 400 Ethyl acrylate - Skin.................. 25 Ethyl alcohol (ethanol)............... .1.000 Ethylamine........ .................. ....... 25 C Ethylbenzene........................... ... 200 Ethyl bromide--............ ............. 200 Ethyl chloride____________ ___ .1,000 Ethyl ether--......... ..................... 400 Ethyl formate_______ __________ 100 C Ethyl mercaptan ............... ......... 20 Ethyl silicate___ _____________ . 100 Ethylene cnlorohydrin - Skin__ 5 Ethylcnediamine . + C Ethylene glycol dmibate Skin Ethylene latino - Skin_________ Ethylene oxide------------------------ 2-Ethoxyethanol (Celloaolve) Skin_________ 2-Ethoiyetnanol 10 0.2 5 50 200 (Celloaolve) - Sktn............... 200 2-Ethoxyetpylacetate (Celloaolve acetate) Skin ... 100 me/**** 860 2.8 290 35 25 " 1 5 1 1.5 0.2, 360 > 600 0.1 0.5 1.400 IX 1,900 45 870 890 2,6X 1,2X 300 52 850 16 30 1.2 9 X 740 740 540 Sublttiin ppm* He/kt**- i Ferbarn (ferrif dimethyl dithiocarbamate)...................... -- 15 Ferrovanadium dust ................... Fluoride (as F) ..... ................... _ 1 2.5 Fluorine.... ....... .......................... 0.1 0.2 Fluorobichloromethane....... ....... 1, 000 S.6X C Formaldehyde.................. ........ . Furfural.......... ... .......................... 5 5 6 20 Furfuryl alcohol.......................... X 2X Gasoline...................................... sx 2. OX Glycidol (2, 3-Epoxy-1- propanol)...... ........ ........ ......... X IX Heptachlor (1, 4, 5. 6, 7, 8, 8a-lwptachloro-3a, 4, 7, 7a-tatraftydro-4, 7methanoindane....... .... ............ -- 0.5 Heptane (n-heptane).........-....... sx 2. OX Hexane (n-hexane).... ............. . 500 1.8X Hexanone (methyl butyl ketone) IX 410 sec-Hexyl acetate............... . X 295 Hexone (methyl isobutyl ketone) IX 410 + Hydrazine - Skin............. .......... 1 1.3 Hydrogen bromide...__________ 3 10 C Hydrogen chloride____ ________ 5 7 Hydrogen cyanide-Skin_______ 10 11 Hydrogen fluoride.......... ........ .. 3 2 Hydrogen peroxide, 90%.----- ---- 1 1.4 Hydrogen selenide............. ......... t Hydrogen sulfide......................... 0.05 - 0.2 - iiydroquinone_____________ ___ 2 'C iodine...... ......... .................... ..... 0.1 .1 Iron oxide fume______________ 15 Isophorone___________________ 25 IX Isopropylamine. 5 12 isopropyl glycidyl ether (IGE).... Ketone..... .................................... Lead---------------------------- ----- X O.S 240 0.9 0.2 Load arsenate...................... ...... 0.15 Lindane (hexachlorcyclohexane. gamma isomtf).... .... ............... 0.5 Lithium hydride.... .. ....... ........... 0.025 1-1964 Addition er deletion of "C" t1964 Riviiicn im TtfiMfiv* Valves i 01 023 0670 Svbatotiep ppm* Magnesium oxide fume............... - Malatnion (0,0-dimethyl dithiophospnate of diethyl metcaptosuccinate)- Skin...... - C Manganese................................... - Mercury - Skin............................. - Mercury (organic compounds) - Skin.......................................... - Mesityl oxide............................... 25 Methoxychlor (2. 2-di-p- methoxy-phenyl -1. 1, 1- trichioroethane)........................ - Methyl acetate............................. 200 Methyl acetylene..........................1,000 Methyl acrylate - Skin................ 10 Methyiai (dimethoxymethane)..... 1,000 Methyl alcohol imetnanol).......... 200 C Methyl bromide Skin................... 20 Methyl cellosolve (2-memoxy- ethanol) - Skin.......................... 25 Methyl cellosolve acetate (ethylene glycol monomethyl ether acetate) Skin................. 25 C Methyl chloride...... .................... 100 Methyl chloroform (1, 1, l-tri* ch loroethane)............................. 350 Methylcyciohexane...................... 500 Methylcyclohexanol................ 100 Methylcyclohexanone................... 100 Methyl formate.............................. 100 Methyl isobutyl carbinol (methyl amyl alcohol)....... ...... 25 t Methyl mercaptan....-........ .......... - C a Methyl styrene------------- 100 Methylene chloride (dichloromethane).................... 500 Monomethy I aniline - Skin.......... 2 Molybdenum ( soluble compounds)....... .... .....-...... .... - (insoluble compounds)........... - M#/M*** IS IS 5 0.1 0.01 100 IS 610 1,6S0 35 3,100 260 80 80 120 210 1,900 2,000 470 460 250 100 - 480 1,750 9 5 15 +1964 Addition or dolorion of MC*' T1964 Rovmon * m* Tmntivo Volwoi v 10 Swbstonc* ppm* M*/M*** Naphtha (coal tar)........................ 200 800 Naphtha (petroleum)................. .. 500 2,000 0 Naphthylamine...................... - A2 Nickel carbonyl.......................... 0.001 0.007 Nicotine Skin........................... - 0.5 Nitric acid................................. r. - p-Nitroaniline Skin................ 1 6 Nitrobenzene - Skin.................... 1 5 Nitroethane-................................. . 100 310 : Nitrogen dioxide....................... 5 9 Nitroglycerin - + EGON - Skin 0.2 2 Nitromethane............................. .. 100 250 1-Nitropropane............................ 25 90 2-Nitropropane......................... .. 25 90 N Nitrosodimethylamme (Di- methylnitrosammei Skin A3 - Nitrotoluene - Skin.................... 5 30 Octane:........................................ .. 500 2,350 Oil mist (mineral)..................... - 5 Osmium tetroxide....................... - 0.002 Ozone..................... ................... 0.1 0.2 ParathionfO, O-diethyl O-P- mtrophenyl thiophospnate) Skin....................................... -- 0.1 Pentaborane............................... 0.005 0.01 Pentachloronaphthaiene Skin. -- 0.5 Pentachiorophenol Skin.......... - 0.5 Pentane ..................................... .1,000 2,950 Pentanone (methyl propyl -ketone).................................... 200 700 Perch loroethyiene <tetri chloroethylene)....................... 100 670 Perchloromethyl mercaptan....... 0. 0.8 Perchloryl fluoride..................... 3 13.5 Phenol-Skin............................... 5 19 Phenyl glycidyl ether (PCE)..... 50 310 Phenylhydiaaine Skin.............. 5 22 Phosdrin (2-carbomethoxy 1 methyl vinyl dimethyl phosphate)............................... 0.1 1964 Addition or dolofion of "C" T1964 Rovioion - too Tontotivo Volvo* 11 01 023 0671 Substance ppm' Me/***" 1 Phosgene icarbcnyl chloride).... Phosphine.................................... Phosphoric acid........................... Phosphorus (yellow)................... Phosphorus pentachlonde......... Phosphorus pentasulfide........... Phosphorus trichloride............... Picric acid Shin....................... Platinum (Soluble Salts)............. propyl acetate............................. propyl alcohol (isopropyl alcohol).................................... Propyl ether (isopropyl ether).... n-Propyl nitiate......................... Piopytene dichloride (1, 2dichletoptopane)..................... Propylene imme - Shin............... Propylene oxide.......................... Pyrethrum.................................... Pyridine...................................... Qumone........................................ Rotenone (commercial)............... 1 Selenium compounds (as Se)..... Sodium fluoioacetate (1060) - Shin........................................ Sodium hydroxide......................... Stibine.......................................... Stoddard solvent ......................... Strychnine..................................... C Styrene monomer (phenylethylene)..................... Sulfur dioxide.............................. Sulfur hexafluoride..................... Sulfuric acid................................. Sulfur monochloride.................... Sulfur pentafluottde..................... Sulfuryl fluoride...................... . 2, 6, 5T (2, 4, 5 biehlorophenoxyacetic acid).. TEDP (tetraethyl dithionopyrophosphate) Shin.. 0.3 0.5 - 200 _ 0.4 1 0.1 1 1 3 0.1 0.002 840 400 960 500 2.100 25 110 75 25 100 5 0.1 - 350 60 240 5 15 0.4 5 - ; 0.1 500 -- 0.05 2 0.5 2,900 0.15 100 420 5 13 1,000 6,000 -1 16 0.025 0.2S 5 20 -- 10 0e 2 + 1964 A4ditle delation of "C" T1964 Ritiiioi >ao Tentative Volvo* 12 Svbstoncr ppm* Mg. M1" Teflon <R) decomposition products................................. - A4 TEPP (tetraethyl pyro- phosphate i Shin.................... - * Tellurium.................................. - 0.05 0.1 1. 1. 2. 2-Tetrachloioethane Skin....................................... 5 35 Tetranydroluran........................ 200 590 Tenanitromethane..................... 1 8 Tettyl (2, 4, 6-lnnitrophenyl- methylnitrammei - Shin........ - 1.5 Thallium (soluble compoundsi - Shin...................................... Thu am (tenametnyl thiuram - 0.1 disulfide i 5 Titanium dioxide........................ IS * Toluene (toluolL....................... 200 750 o Toluidine - Shin .................. 5 22 CTolylene-2. 4'dnsocyanate. .. 0.02 0.14 Trichloroethylene...................... 100 TncMoronaphthaiene-Shin...... _ 520 S 1, 2. 3-Tricoloropropane........ 50 300 1, 1, 2'Trichloro 1, 2, 2- trif luoroethane........................ .1.000 7,600 Triethylamine.............................. . 25 100 Tr ifluoromonobromomethane...... .1,000 6.100 Tr mitrotoluene Shm.................. Triorthoctesy! phosphate.......... Tnphenyl phosphate.................. _ 1.5 0.1 3 Turpentine................................. 100 560 Uranium isoluble compoundsi ... 0.05 (insoluble compounds).......... 0.25 C Vanadium (V aO a dust)............. . ' (VaO a fume)........................... 0.5 0.1 C Vinyl chloride (chloroethylenei. 500 Vinyl toluene ........................... . too 1,300 480 Warlarm (3 - !~a acetonylberuyl hydroxycoumarin).................... 0.1 C Xylene (xylol)................ . 200 870 Xylidine Shin.............. * 25 1*64 Addition or deletion of "C" t!964 Revision see Tentative Values 13 01 023 0672 Substone* ppm* Mp/H*** r Yttrium.......................................... Zinc oxide fume.......................... Zirconium compounds (as Zr).... - '5 S Radiaaetivit?: For ptrmutibit co*cantr#tint of robio-itotoMs m nr. m U. S. Daoartmant of Comm#fe. National Burtau of Standard*. Handbook 69. "Moitmum Parmiisibit Bod? Burdens and Maumum Parnfisaibio Ccncontrafton* of Radi* onucudas m Air and m watar for Occupational Eiposura." iun* i 1999. Also, sot U. S. Ocoartmont of Commrc National Buraau of Standards. Handbook S4 "Pormistipia Dot* from Eiternat Sources of lonmni Radiation.'' Seotemoof 24. J944. and addendum of Afttit IS. 195S. Parts of vapor or ias per million parts of air by volume at 2$*C and 760 mm. H| pressura. aporoaimate miiii|rams of particulate Pdf cubic meter of air. A Numbers. See Aboendt* A f T1964 Roviaion Tontotiuo Volvo* t MINERAL OUSTS Sabstttm m.p.p.e.f.* SILICA Crystalline Quartz. Threshold Limit calculated 250 * from the formula.................. %SiOw 5 Cnstobalite Amorphous including natural diatomacaous earth _______________ 20 SILICATES (lass than 1% crystalline silica) Asbestos ___________________________ S Mica ________________________________ Soapstone ____________________________ Talc _________________________________ Portland Cement SO 20 20 20 "Inert" or Nuisance Particulate* SO (or IS mg/m* whichever is the smaller) Conversion factors mppcf x 35.3 " million particles per cubic meter = particles per ex. . Miiiien of permit! per cubic tpot pi air. feeMO e rmpmttf wnipies com*** Mr ligM-llpie tectialcs. TM percpMae* ef crytteHlw mice in me farmile n tne enmmt eetenumee mm mr-eomt smraiti. eicept m moce nettnen ip muck otter mettaes neve been mown re ee epplicewe. 14 TENTATIVE VALUES Subttoneo ppm* M M1** Anisidine (0. p-isomersi.......... Benzoyl peroxide........................ Calcium oxide............................ ++Carbaryl (Sevm) (R).................. Copper Fume........................... Ousts & Mists...... Cotton Dust daw)...................... Cyelopentadiene........................ 75 Demeton (Systox) (R)................ 1, 3-Oicnioro-S. 5-dimetnyl hydamoin............................... Dimethyl 1, 2-dibromo-2, 2- dichloioethyl phosphate. (Oibromi (Ri ..................... Dimethylamme............................. 10 + Dimethylformamide Skin . 10 h-Oi sec. octyl pntnaiate (Di 2- ethythexyt.phthaiate)............. Epichlorhydr in............................. - 5 Ethanolamine............................... 3 Graphite....................................... - Hatmum....................................... - H-Mexacnioroethane . Skin............. 1 Hydrogen Sulfide......................... 10 L. P. G. (tow pressure gas) (Liquid petroleum gasi............1.000 Maleic anhydride........................ - Methane..........................................1.000 Methyl acetylene-propadiene muitute, (MAPP) ............. 1,000 Methytamtne................................ 25 * Methyl mercaptan...................... 10 Methyl methacrylate 100 C Methylene bis phenyl isocyanate 0.02 Mineral wool, fibrous glass...... - Monomethyl hydrazine Skin.... Mttphotine Skin........................ 0.2 20 0.5 5 5 5 0.1 1.0 1 200 0.1 0.2 3 IS 30 5 19 6 ISmppcf 0.5 9.7 15 - S - - 31 20 410 0.2 2 035 70 Peru OI neper or |p$ por million pent or r br roiumt at 29*C and 7BO mm. N| pranura. "* Apprpaimat* militframs ef parttcuiafa par cubic matar of atr. *1964 RaviiiM, **1944 AMiliwie. 15 01 023 0673 r Subfttenc* ppm* pM`" Naphthalene................................. 10 Nickel, metal and soluble compounds............................... Nitiie Acid ................................. 2 p-Nitrochloio&enzene................. -- -H-Nitiogen bifluoiide.....................' 10 C ++Oxygen difluonae....................... 0.05 ++-p Phenylene diamine - Skin....... -- Phosgene.................................... 0.1 +Phtnalic anhydride........ ............ 2 h- Propane......................................... 1,000 P Propiolactone.................... -.... +Selemum compounds................... - Silver, metal and soluble com* pounds..................................... Tantalum..................................... 1, 1, 1, 2-Teoachloro-2, 2-difluoioethane..................... 500 1, 1, 2, 2'Tetrachloro-l, 2-ditluoieothane..................... 500 Teoaetnyl load-Skin................. Tm (inorganic compounds).____ - (organic compounds as Sn| - Skin........................................ Yttrium......................................... - SO 1 5 1 29 0.1 0.1 0.4 12 1.800 ; A5 0.2 0.01 5 4, 170 4, 170 0.075 2 0.1 1 * Pent ef vaoei or cm eer minis* asm or air y ooism* tl ZS*C one TOO mm. H| pressure. aaersumato miiliiramt of particulate aar caWc motor of mr. a oumeort. too aaaoflOii A 1964 Revisions. ++1964 Additions. Appendix A 1' knaAtt. Because of high incidence of bladdet tumors in mao, any exposure, includinf skin, is extremely hazardous. A* -KsnttkyU*tat. Because of the extremely high incidence of bladder tumors m workers handling this-compound, and the inability to control ex posures, fl-naohthyiamme nas been prohibited from manufacture, use and other activities that in volve human contact by the State ol Pennsylvania. 16 A1 M-NitrsudimothytamiM. Because of extremely nigh toxicity and presumed carcinogenic potential ol this compound, contact by any route should not be permitted. A4 Taka decomposition predicts. Al least one identi fied component of Teflon decomposition products is extremely toxic, but in the absence ol more complete toxicity information and suitable analytic methods, a definite Threshold Lirnil Value is not recommended at this time; but air concentrations should be minimal. A fl-Prepielacteal. Because of high acute toxicity and demonstrated skin tumor production in animals, contact by any route should be avoided. Appendix B B. 1 THRESHOLD LIMIT VALUES FOR MIXTURES When tern or more hazardous substances are present, their combined effect, rather than that of either indi vidually. should be (men primary consideration, la the absence ef ieforaibea te the ceotnry, tkt effects et Ik differsat hazards should k considered as additive. That is. if the sum of the following fractions, C. + C. + ... Cn T- TT Tn exceeds unity, then the threshold limit of the mixture should k considered as king exceeded. Ct indicates the observed atmospheric concentration, and T- the corres ponding threshold limit, (See Example lAaJ. Exceptions to the above rule may k made when there is good reason to kfieve tkt the chief effects of the different harmful substances are not in feet additive, butindependent as when purely local effects on different organs of the body are produced by the various com ponents of tk mixture. In such cases tk threshold limit ordinarily is exceeded only when st least one memkr of tk series <C> or C* etc.) itself has a value tr exceeding unity, (See Example lAb.). Antagonistic action or potentiation may occur with some combinations of atmospkric contaminants. Such cases at present must k determined individually. Poten tiating or antagonistic agents are not necessarily harm ful by themselves. Potentiating effects of exposure to suen agents by routes other than tkt ol inkiation Is also possible, e g. imbibed alcohol and mkled narcotic itiiehioroothyienti Potentiation is characteristically ex hibitao at high concantraimns. loss probably st low 17 l 01 023 0674 When a given operation or process characteristically emits a number of narmlui Ousts fumes, vapors O' gases 't wii frequently be only feasible to attempt to evaluate the hazard by measurement of a single sub stance In such cases, the threshold limit used lor this substance should be reduced by a suitable factor the magnitude of which will depend on the number, toxicity and relative quantity of the other contaminants ordi naniy present Eiampies of processes which are typically associated with two or more harmful atmosoneric contaminants art welding automobile repair, blasting, painting, lacquering, certain foundry operations diesei eihausts. etc tEiampie 2i f THRESHOLD LIMIT VALUES FOR MIXTURES EXAMPLES )A General case, where air is analyzed tor each com ponent. a AODITIV! EFFECTS Air contains S ppm of carbon tetrachloride (TIV 10). 20 ppm of ethylene dichloride (TLV.50I and 10 ppm of ethylene dibromide. (TIV. 25). 5 20 10 65 ., ir~io~!r"Kr"1-3 Threshold limit is eiceeded. INDEPENDENT EFFECTS Air contains 0.15 mg/m* of load (TIV, 0.2) and 0.7 mg,m* of sulfur* acid (TIV, U 075 -51 - 0.7 0.20 1 Thiealiold limit is not exceeded. 18. Special case when source of contaminant is a muture and atmospheric composition is assumed similar to that of original material, i.e. vapor pres sure of each component is the same at the observed temperature. a ADDITIVE EFFECTS, appronmaie solution. 1 A mature ol equal parts 111 trichloroethylene (TIV 100) and (2) methyl chloroform ITIV 3501 ig C 100 x C350 ** c... T1 Solution applicable to spot solvent mature usage where an or nean an. solvent evaporates 0 o1 !l Tc~ c. c 2C TOO ~ 350 " T,,, 7C. 2C 2C 700 700 * T,,, T,,. - 700 x i -- 155 ppm IB b General Esact Solution foi Mutures ot N Com ponents With Additive Effects and Oitterent vapor Pressures 1,1 + x - - 1; C, + C, t- . (2.1) -i- + x C. - T; - -- 1. 8y the Law of Partial Pressures. ( C, --ap,. And by Hamit's Law. > P.-F, pi*. Combme 13) and 14) to obtain IS) C, -- eF,p,*. Combining (U B.1L and I5X we obtain +... + and sohrrng for T. n t F,p,* Fa* + ..*+ Fa* r" ft8--:---------- rr* * i--n X (12) r-i-i i--a x -I Fa* Fa* Tr * 19 01 023 0675 [ T s Threshold limit Value in ppm C = Vapor concentration m ppm p = Vapor pressure oPcomponent in solution. p* = Vapor pressure of pure component. F ss Mol fraction of component m solution a = A constant of proportionality Subscripts 1.2. . . . n relate the above quantities to components 1.2. . n. respectively. Subscript refers to an arbitrary component from 1 to n. Absence of subscript relates the quantity to the mirture. J Solution to be applied hen there is a reservoir of the solvent muture whose composition does not change appreciably by evaporation Exact Arithmetic Solution of Specific Muture Mol wt Density T Trichloro ethylene 11: 131.4 1.46 g'lttl 100 P* at 25 *C Mol trac tion in half-and half solu tion by volume 73mm Hg 0.527 Methylchloroform 12) 133.42 1.33 g; ml 350 125mm Hg 0473 F,p,'-(0.527) (73)- 38.2 Fjp,0 -- (0.473) (125) -- 59.2 T = 38.2 4- 59.2 * 87.41 (350) - 87.4! (350) = 177 312 + 592 1332 + 592 193.0 100 350 T = 177 ppm (Note difference in T.L.V. when account is taken of vapor pressure and mol fraction m comparison with above esampfe where such account is not taken). 20 2. A muture of one part of (!) parathion OlV and two parts of (2) EFN (TLV. 0.51 A , C, 0.1 + IT C_ C. - 2C, 0.! C.-3C, A , 2C, 0.1 + TF 3C, 7C, 3C, "0T " 1.5 T-- -- 0.21 mg/m* 1C. T. L. V. for Mixtutos of Mineral Ousts. For mixtures of biologically active mineral dusts the general formula tot mixtures may be used. With the ex ception of asbestos, pure minerals are assi pied TLVs of 2.5, 20 or 50. For a mixture containing 80% talc and 20*v quartz, the TLV for 100% of the mixture *`C" is given by: _C___18, 02 TLV ' 20 2.5 TLV -j-j- = 8.4 mppcf , Essentially the same result will be obtained if the limit of the mote (most) toxic componot is used provided the effects are additive. In the above example the limit for 20% quartz is 10 mppcf. Fot another mixture of 25% quartz 25% amorphous silica and 50% talc: S^O^O^Mmppcf The limit for 25% quartz approximates 8 mppcf. 21 01 023 0676 Appendix C BASES FOR ASSIGNING LIMITING "C" VALUES By definition in the Preface, a listed value heat ing a "C" designation refers to `ceiling' value that should not be exceeded; all values should fluctuate below the listed value. In genetai the bases for assigning or not assigning a ``C" value rest on whether excursions of concentration above a proposed limit for periods up to IS minutes may result in ai intolerable irritation, b) chronic, or irreversible tissue change, or cl narcosis of sufficient degree to increase accident pioneness. impair self rescue or materially reduce work efficiency. r In order for the Committee to decide whether a sub stance is a candidate for a "C" listing, some guidelines must be formulated on the permissive fluctuation above the limit in terms of the seriousness of the response in the categories a, b. c. given above. For this the factors given in the table below have been used by the Committee. For both technical and practical reasons, the factors have been pegged to the concentration in an inverse manner. It will be noted that as the magnitude of the T. L. V. increases a correspondingly decreased range of fluctuation is permitted; not to decrease the factor for T. L. V.'s of increasing magnitude would permit exposures to large absolute quantities, an undesirable condition, a condition that is minimized at low T. L. V.'s. More over larger factors at the lower T. L. V.'s are con sistent with the difficulties in analyzing and con trolling trace quantities. T.I.V. in'Mii Mni/i Tw rTm.C.Vt. la_a_m_m. 0 to 1 1 - to 10 - 3 Toluene diisocyanate-T. L. V.. 0.02 ppm. if permitted to lise above 0.06 ppm may result m sensitization in a single sub sequent exposure. "C" listing recommended on category 0. 2 Maganese-T. L. V.. 5mg m\ contains little or no safety factor. All values should flucuate below 5mg m'. "C" listing recommended on category b. 22 f.t.v. T* aaasi t.lv. Sm* *r mgsmi Saner 101- to 100 1.5 100 to 1000 1.25 (aaneiar Methyl stytene-T. L. V. 10C if encountered at levels of 150 ppm will prove intense ly irritating, "C" listing recommended on category a. Methyl ehloroform-T. !_ V. 350ppm. at 438 ppm for per iods not exceeding 15 min utes is not expected to re sult in untoward effects relating to categoiy c. No ``C*' listing recommended. * Whichever unit is applicable As stated in the preface, the same factors may be used as guides for reasonable excursions above the limit for substances to which the time-weighted avetage applies. The time-weighted average implies that eacn excursion above the limit is compensated by a com parable excursion below the limit. Harry B. Ashe E. J. Baier Allan L. Coleman Harvey B. Elkins Bernard Grabois Wayland J. Hayes. Jr. Heith Jacobson Harold N. MaeFarland. Consultant E. Mastromatteo William F Remdollar Russel G. Scovill Ralph G Smith Mitchell R Zavon Herbert E. Stokmger. Chairman 23 01 023 oen l