Document Jw51pwQ9gY8ZD7g01DD2JRY6

Threshold Limit Values of Air-borne Contaminents For 1968 RECOMMENDED AND INTENDED VALUES Adopted at the 30th Annual Meeting of the American Conference of Governmental Industrial Hygienists, St. Louis, Missouri, May 13. 1968. ) TX TINER RMC0042488 Copyright 1968, by American Conference of Governmental Industrial Hygienists. The American Conference of Governmental Industrial Hygienists will welcome requests for permission to republish or reprint these Threshold Limit Values. Requests for such permission should be directed to the Secretary-Treasurer, 1014 Broadway, Cincinnati, Ohio 45202. Price Each 1 - 49 Copies.................................................................. 50^ 50 - 999 Copies............................................................. 49^ 1000 - 4999 Copies.......................................................30^ 5000 or more Copies...................................................15i The 2nd edition of the Documentation of Threshold Limit Values, is currently out of print. Information concerning availability of reprints should be directed to the Secretary -- Treasurer. The Documentation should be consulted when using the Threshold Limit Values herein. THRESHOLD LIMIT VALUES FOR 1968 The Threshold Limit Values reier to air-borne concentra tions of substances and represent conditions under which it is believed tliat nem lv all workers mav be repeatedlv exposed, dav after dav. without adverse eftert Because of wide varia tion m individual susceptibility, exposure .>t an occasional individual at or even below the threshold limit mav not prevent disconiioi-;. aggravation oi a pre-existing condition, or occupa tional llllIvSS. Clinical tests are becoming available that permit detection oi those individuals who will hyperreact upon exposure to certain industrial substances. Being predictive m character, they may be applied as screening tests in the preplacement job examination. Requests for further details of these tests should be directed to the Chairman oi the Committee. 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 concentrations. Exceptions are the substances given m Appendix A and certain of the substances given a C" listing. The values not given a "C" listing reier to time-weighted average concentrations for a conventional Tor 6 hour workday. Time-weighted average concentrations permit excursions above the limit, provided they are compensated by equivalent excursions below die limit during the work dav. The degree of permissible excursion is pegged to the threshold limit value of the particular substance as given m table m Appendix C under "Test TLV Factor." Hence, it is not considered appro priate to interpret air concentration values as exceeding timeweighted average limits, if such values lie within the per missible excursions. iSee section on Legislative Code.) The amount by which these concentrations may >e exceeded for short periods without injury to health depends upon a num ber oi tactors such as the nature of the contaminant, whether very high concentrations even for short periods produce acute poisoning, whether the effects are cumulative, the fre quency with which high concentrations occur, and the duration oi such periods. All must be taken into consideration in arriving at a decision as to whether a hazardous situation exists. Enlightened industrial hygiene practive inclines toward con trolling exposures below the limit rather than maintenance at the limit. Threshold limits are based on the best available informa tion from industrial experience, from experimental human and animal studies, and when possible, from a combination of the three. The basis on which the values are established mav differ from substance to substance: protection against impair ment of health may be the guiding factor for some, whereas reasonable freedom from irritation, narcosis, nuisance or other forms of stress may dominate the basis for others. The Com mittee holds to the opinion that limits based on physical irrita tion should be considered no less binding than those based on 1 / TX TINER RMC0042489 physical impairment: growing bodies of evidence indicate that physical irritation mav promote and accelerate physical impair ment. These limits are intended for use in the field of industrial hygiene and should be interpreted and applied only by persons trained m this field. Thev are not intended for use. or for modi fication for use. U) 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. t3) in estimating the toxic potential of continuous uninterrupted exposures. (4i as proof or disproof of an existing disease or physical condition, or (51 for adoption by countries whose working conditions differ trom those in the United States of America and where substances and processes differ. Documentation of Threshold Limit Values. A separate companion piece to the TLVs is issued by AGGIH under this title. This publication gives the pertinent scientific information and data with reference to literature sources that were used to base each limit. Each documentation also contains a state ment defining the type of response against which the limit is safeguarding the worker. For a better understanding of the TLVs it is essential that the Documentation be consulted when the TLVs are being used. Ceiling vs Time-Weighted Average Limits. Although the time-weighted average concentration provides the most satis factory. practical way of monitoring air-borne agents for com pliance with the limits, there are certain substances for which it is inappropriate. In the latter group are substances which are predominantly fast acting and whose threshold limit is more appropriately 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 de finitions that the manner of sampling to determine compliance with the limits for each group must differ; a single brief sample, that is applicable to a C" limit, is not appropriate to the time-weighted limit: here, asufficient number of samples are needed to permit a time-weighted average concentration throughout a complete cycle of operations or throughout the work shift. Whereas the ceiling limit places a definite boundary which concentrations should not be permitted to exceed, the timeweighted average limit requires an explicit limit to the ex cursions that are permissible above the listed values. The magnitude of these excursions may be pegged to the magnitude of the threshold limn by anappropnate factor shown in Appendix C. It should be noted that the same factors are used by the Committee in nuking a judgment whether to include or exclude a substance for a C" listing. "Skin" Notation. Listed substances followed by thedesignation Skin" refer to the potential contribution to the over-all exposure bv the cutaneous route including mucous membranes and eye. either by air-borne, or more particularly, by direct contact with the substance. Vehicles can alter skin absorption. 2 l v This attention-calling designation is intended to suggest appro priate measures for the prevention of cutaneous absorption so that the threshold limit is not invalidated. These values are reviewed annually by the Committee on Threshold Limits for revision or additions, as further in formation becomes available. Mixtures. Special consideration should be given also to the application of these values m assessing the health hazards which may be associated with exposure to mixtures of two or more substances. A brief discussion of basic considerations involved in developing threshold limit values for mixtures, and methods tor their development, amplified by specific examples are given in Appendix B. "fnerc" or Nuisance Particulates. A number of dusts or particulates that occur m the working environment ordinarily produce no specific effects upon prolonged inhalation. Some insoluble substances are classed as inert (e.g. iron and steel dusts, cement, silicon carbide, titanium dioxide, cellulose): 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 (vegetable oils, glycerine, sucrose). In the case of the insoluble substances, there may be some accumulation in the respiratory passages, fn the case of the soluble substances, this accumulation will ordinarily be temporary but may inter fere to some extent with respiratory processes. Hence, it is desirable to control the concentrations of such particulates in the air breathed by any individc.,.1, in keeping with good industrial hygiene practice. 3 A threshold limit of 15mg/m , or 50 mppcf. whichever is less, is recommended for substances m these categories and for which no specific threshold limits have been assigned. This limit, for a normal work day, does not apply to brief exposures at higher concentrations. Neither does it apply to those sub stances which may cause physiologic impairment at lower con centrations but for which a threshold limit has not yet been adopted. Some "inert" particulates are given in Appendix D. Simple Asphyxiants - "Inert" Gases or Vapors. A number of gases and vapors, when present m high concentrations in air. act primarily as simple asphyxiants without other signi ficant physiologic effects. A TLV may not be recommended for each simple asphyxiant because the limiting (actor is the available oxygen. The mimmil oxygen content should be 18 percent by volume under normal atmospheric pressure (equi valent to a partial pressure, pO^ of 135 mm ffg). Atmospheres deficient in 0^ do not provide adequate warning and most simple asphyxiants are ordorless. Several simple asphyxiants present an explosion hazard. Account should be taken of this factor m limiting the concentration of the asphyxiant. Physical Factors. It is recognized that such physical factors as heat, ultraviolet and ionizing radiation, humidity, abnormal 3 * 5. * l TX TINER RMC0042490 pressure and itie like may place added stress on the body so :!u; the efiects irom exposure at a threshold limit may be altered. Most of these stresses act adversely to increase the tvxic response oi a substance. Although m>s: threshold limits have built-m safety lactors to guard against adverse eifects i moderate deviations from normal environments, the safetyfactors of most substances are not oi such a nugnitude as to take care oi gross deviations. For example, continuous work at temperatures above 90F or over-time extending the work week more than 50.'. might be considered gross deviations. In such instances judgment must be exercised in the proper adjustments of the threshold limit values. Notice of Intent'1 At the beginning of each year, proposed actions oi the Committee for the forthcoming year are issued in the form of a "Notice of Intent." This Notice provides not onlv an opportunity for comment, but solicits suggestions of substances to be added to the list. The suggestions should be accompanied by substantiating evidence. As Legislative Code. The Conference does not consider the Threshold Limit Values appropriate matter for adoption m legislative codes and regulations and recommends against such use. If. however, the list is so used, the intent of the concepts contained m the Preface should be maintained and provisions should be made to keep the list current. Reprint Permission. This publication may be reprinted provided that written permission is obtained from the Secre tary-Treasurer of the Conference and that it be published in its entirety. RECOMMENDED VALUES (In Alphabetical Order) Subtton Acetaldehyde.......................................... Acetic acid ........................................... Acetic anhydude................................... Acetone.................... Acetonitrile............................................. Acetylene dichloride, see 1.2 Dicloro- ethylene ............................................... Acetylene tetrabromide.......................... Acrolein................................................... Acrylamide*S kin.................................... Acrylonitrile-Skin................................... Aldrin-Skin ............................................. Allyl alcohol-Skin............................... . AUyl chloride......................................... C Allyl glycidyl ether (AGE).................. Allyl propyl disulfide........................... 2-Aminoethanol. see Ethanolamine....... 2*Aminopyf idine..................................... Ammonia ................................................. Ammonium sulfamate (Animate)............ n-Amyl acetate....................................... sec-Amyl acetate.................................... Aniline-Skin .......................................... Anisidine (0, p-isomers)* Skin............. Antimony & compounds (as St>).............. ANTU (alpha naphthyl thiourea)............ Arsenic & Compounds (as As)............... Arsine ..................................................... Azinphos - methyl - Skin.......................... Barium (soluble compounds).................. C 8enzene (benzol)-Skin.......................... Benzidine*Skin...................................... p-Benzoquinone, seeQuinone.............. Benzoyl peroxide................................... Benzyl chloride..................................... Beryllium................................................. Biphenyl, see Diphenyl........................ Boron oxide............................................ C Boron trifluoride ................................... Bromine......................... ................ ........ Bromoform-Skin...................................... Butadiene (1.3-butadiene)................... 8utanethiol, see Butyl mercaptan ...... a) b) ppm Mj'MJ 200 10 S 1.000 40 360 25 20 2.400 70 1 0.1 20 2 2 10 2 14 0.25 0.3 45 0.25 5 3 45 12 0.5 2 50 35 15 100 525 125 650 5 19 0.5 0.5 0.3 0.5 0.05 0.2 0.2 0.5 25 80 A' 5 15 0.002 15 13 0.1 0.7 0.S S 1.000 2.200 a) Parts of vapor or gas par million parts of contaminated air by volume ot 25 C ond 760 mm. Hg pressure. b) Approximate milligrams of particulate per cubic meter of air. A Numbers. See Appendix A 1968 Addition See Notice of Intended Changes / TX TINER RMC0042491 Subifanc* o) b) Ppm Mg/M 2-Butanone.................................................... 200 590 2-Butoxy ethanol (Butyl Cellosolvei-Skin .. 50 240 Butyl acetate (n-butyl acetate)................... 150 710 n-Butyi acetate ............................................ 150 710 sec-Butyl acetate........................................ 200 950 tert-8utyl acetate .................... 200 950 Butyl alcohol................................................ 100 300 sec-8uty( alcohol............................. tert. Butyl alcohol ..................................... 150 450 100 300 C Birtytarntne-Skin......................................... C tert. Butyl chromate (as Cr03)-Skm.......... 5 15 - 0.1 n-Butyl glycidyl ether (BGE)...................... 50 270 ** Butyl mercaptan............................................ 10 35 p-teit. Butyltoluene................................... IQ 00 Cadmium (Metal dust and soluble salts)..... -- 0.2 * Cadmium oxide ft/me............................................ Calcium arsenate........................... - 0.1 -1 Calcium oxide................................................ -5 Camphoi......................................................... Caibaryl (Sevin) (R)...................................... -2 -5 Carbon black.......................................................... - 3.5 Carbon dioxide.............................................. 5.000 9,000 Carbon disulfide-Skin..................... 20 60 Carbon monoxide.......................................... Carbon tetrachlonde-Skin............................ 50 55 10 65 Chlordane-Skin.............................................. - 0.5 Chlorinated camphene, Skin ..................... - 0.5 Chlorinated diphenyl oxide ........................ - 0.5 C Chlorine........................................................ 13 Chiorine dioxide ........................... .............. 0.1 0.3 C Chlorine trifluoride..................................... 0.1 0.4 C Chloroacetaldehyde..................................... 13 -Chlo<oacetophartone (phenacylchloride).. 0.05 0.3 Chlorobenzene (monochlorobenzene) ......... o*Chlotobenzylidene malononitriie 75 350 (0C8M).......................................................... 0.05 0.4 Chlorobromomethane.................................... 200 1. 050 2*Chtoro-1,3 butadiene, see Chtoroprene.. Chlorodiphenyl (42% chlorine)-Skin ........... -1 Chlorodiphenyl (54% chlorine)-Skin ........ -- 0.5 1, Chloro, 2.3 epoxypropane, see Epichlorhydrin............................... 2, Chloroethanol. see Ethylene chlorohydrin................................... . Chloroethylene, see Vinyl chloride C Chloroform (trichloromethane).................... 50 240 1-Chloio-l-nitropjopane .............................. 20 100 Chloropicrin.................................................. 0.1 0.7 Chloroprene (2-chloro-l, 3-butadiene)-Skin 25 90 Chromic acid and chromates (as Cr03) ..... - 0.1 Chromium, sol. chromic, chtomous salts.. - 0.5 as Cr Metal g, insol. salts............ ..... ....... -1 Coal tar pitch volatiles (benzene soluble fraction) (anthracene, BaP, phenanthrene , acridine, chrysene, pyrene) - 0.2. See Notice of Intended Changes 6 Subttan e ppm b) M&'M3 * Cobalt, metal fume & dust.......................... Copper fume.................................................. - 0.1 - 0.1 Dusts and Mists................ Cotton dust (raw).......................................... - 1-0 -1 Crag (R) herbicide................................................ Cresol (all isomersl-Skm..................................... - 15 5 22 Crotonatdehyde............................,................ Cumene -Skin ........................................................ 26 50 245 Cyanide (as CN)-Skin.......................................... --5 Cyclohexane.................................................. Cyclohexanol....................................... 300 1,050 50200 Cyclohexanone.............................................. Cyclohexene......................................................... 50 200 3001,015 Cyclopentadiene.................................................... 75 200 2,4-0...................................................................... OOT-Skin ...................................................... - 10 -I DDVP-Skin................................................... -1 Decaboiane-Skin .......................................... 0.05 0.3 Oemeton (R)-Skin.......................................... -- 0.1 Diacetone alcohol (4-hydroxy-4-methyl-2- pentanone) ...................................................... 50240 1,2 Diaminoethane, see Ethylenediamine Oiazomethane........................ ..................... 0.2 0.4 Oiborane........................................................ 0.1 0. l C 1,2-Oibromoethane (ethylene dibromide)- Skin.... .................................................................. 25 190 * Dibutyl phosphate........................................ * Oibutylphtfiarate........................................... 15 --S C o-Dichlorobenzene............................... -..... p-Oichlocobenzene.................. 50 300 75 450 Dichlorodifluoromethane.............................. 1.000 4.950 l,3-Oichloro-5, 5-dimethyl hydantoin......... -- 0.2 1,1. -Dichloroethane.................................... 100 400 1.2-Dichloroethane...................................... 50 200 1.2-Dichloroethylene.................................. 200 790 C Oichloroethyl ether-Skin................................ 15 90 Dichloromethane, see Methylenechloride .. Dichloromonofluoromethane........................ 1.000 4,200 C l, 1-Dichloro-l-nitroethane............................ 10 60 1.2-Dichloropropane. see Propylenedi- chloride........................................................ Dichlorotetrafluoroethane............................ 1.000 7, 000 Dieldrin-Skin ................................................ - 0.25 Diethylamine ................................................ Diethylamino ethanol-Skin.......................... 25 75 10 50 Diethylether, see Ethyl ether..................... Difluorodibromomethane............................... 100 860 C Diglycidyl ether (DGE)................................ 0.5 2.8 Dihydroxybenzene, see Hydroquinone....... Diisobutyl ketone ......................... 50 290 * Oiisopropylamine - Skin............................... Oimethoxymethane, see Methylal............... 5 20 Dimethyl acetamide-Sfcin ............ 10 35 Oimethylamine.............................................. 10 18 Dimethylaminobenzene. seeXylidene....... 1968 Addition 7 v i TX TINER RMC0042492 Swbsionce ) , b) Dimethylamline (N-dimethylaniline)-Skin .. Dimethylbenzene. see Xylene............ ....... Dimethyl 1, 2-dibromo-2, 2-dichloroettiyl phosphate, (Dibrom) ............................. Dimethylformamide-Skin.............................. 2.6 Dimethylheptanone, see Diisobutyl ketone.......................................................... 1.1 -Dimethylhydrazme-Skin........................ Oimethylphthalate........................................ Dimethylsulfate Skin ................................ Dimtrobenzene (all isomersi-Skin............... Dinttro-o-cresol-Skin................................... Dinitrotoluene-Skin...................................... Oioxane (Diethylene dioxide)-Skin............. * Oiphenyl........................................................ Diphenylmethane diisocyanate (See Methylene bisphenyl isocyanate (MD!)..... Diptopylene glycol methyl ether-Skin......... Di-sec, octyl phthalate (Di-2-ethylhexylphthaiate............................ ......................... Endrin-Skin.................................................... Epichlorhydrin-Skin...................................... EPN-Skm ...................................................... 1,2-Epoxypropane, see Propyieneoxide .... 2, 3-Epoxy-l-propanol see Glycidol .......... Ethanethiol, see Ethylmercaptan............... Ethanolamine................................................ 2 Ethoxyethanol-Skin .................................. 2 Ethoxyethyl acetate (Cellosolve acetate) -Skin ........................................................... Ethyl acetate................................................ Ethyl acrylate-Skin...................................... Ethyl alcohol (ethanol)................................ Ethylamine.................................................... Ethyl sec-amyl ketone (5-methyl-3-heptanone)............................................................. Ethyl benzene .............................................. Ethyl bromide................................................ Ethyl butyl ketone (3-Heptanone)............... Ethyl chloride .............................................. Ethyl ether..................................... .............. Ethyl formate................................................ C Ethyl mercaptan............................................ Ethyl silicate................................................ Ethylene chlorohydrin-Skin ........................ Ethylenediamine .......................................... Ethylene dibromide, see 1.2-Dibromoethane......................................................... Ethylene bichloride, see 1,2-Dichloroethane......................................................... C Ethylene glycol dinitrate and/or................. Nitroglycerin - Skin 5 25 3 10 30 0.5 1 100 0.2 1 5 5 1 0.2 l.S 360 1 100 600 5 0.1 5 19 0. S 36 200 740 100 400 25 1.000 10 540 1.400 100 1,900 18 25 100 200 50 1.000 400 100 10 100 5 10 130 435 890 230 2.600 1.200 300 25 850 16 25 0.2d> 1 * * d) An atmosphsric concentration of not mot* then 0.02 ppm, or personal protection may bo necessary to ovoid headache. See Notice of Intended Changes 8 Substance Ethylene glycol monomethyl ether acetate, see Methyl cellosolve acetate . Ethylene imine-Skin ............. Ethylene oxide.............................................. Ethylidine chloride, see 1.1-Dichloto- ethane.................................. N-Ethylmorpholine-Skin .. Ferbam.................... Fertovanadium dust . .... Fiuonde (as F) .............. Fluorine ............. ......................... Fluorotnchloromethane . . C Formaldehyde............................................... Formic acid .................... Furfural-Skin................................................ Furfuryi alcohol............................................ Gasoline...................................................... Glycidol (2,3-Epoxy-l-propanol)............... Glycol monoethyl ether, see 2-Ethoxy- ethanol ...................................................... Guthion, see Azinphosmethyl.................. Hafnium.......................................................... Heptachlor-Skm............................................ * Heptane <n-heptane>...................................... Hexachloroethane-Skin................................ * Hexachloronaphthalene - Skin..................... Hexane (n-hexanej........................................ 2-Hexanone.................................................... Hexone ........................................................ sec-Hexyl acetate Hydrazine-Skin.............................................. Hydrogen bromide ........................................ C Hydrogen chloride...................... ................. Hydrogen cyanide-Skin.............................. Hydrogen fluoride ....................................... Hydrogen peroxide, 90o.............................. Hydrogen selenide........................................ Hydrogen sulfide......................... ................ Hydroquinone................................................ Iron oxide fume ............................................ Isoamyl acetate.......................................... Isoamyl alcohol........................................... isobutyl acetate............................................ isobutyl alcohol............................................ Isophorone .............................................-- isopropyl acetate......................................... Isopropyl alcohol.......................................... Isopropylamine............................................. Isopropylether .............................................. isopropyl glycidyl ether (IGE)..................... Ketene............................................................ Lead ............... Lead arsenate Lindane-Skin * 1968 Addition 9 o) b) ppm Mg MJ 0.5 1 50 90 20 94 _ 15 _1 - 2.5 o.:1 0.2 000 5.600 56 59 5 20 50 200 _ A6 50 150 _ 0.5 - 0.5 500 2.000 1 10 _ 0.2 500 1. 800 100 410 100 410 50 300 1 1.3 3 10 57 10 11 32 1 1.4 0.05 0.2 10 15 -2 0.1 1 _ 10 100 525 100 360 150 700 100 300 25 140 250 950 400 980 5 12 500 2, 100 50 240 0.5 0.9 - 0.2 _ 0.15 - 0.5 / TX TINER RMC0042493 Substance Lithium hydride ................................... L. P. G. 'Liauifted petroleum gas)............ Magnesium cx:oe fume Malathion-Skm .......... ... * Maleic anhyflnie......................................... C Manganese ... ........... Mercury-Skin ... Mercury organic compounds'-Skrn Mesityl cxifle Methanethioi. seeMstnyl mercaptan Methoxychlor 2-Methoxyetnanoi. see Methyl cellosoive Methyt acetate ................................... Methyl acetylene rorooynei..................... Methyl acetylene-propaciene mixture <MAPP) ...................................................... Methyl acrylate-Skin............... Methyial 1dimethoxymethanei................. Methyl alcohol (methanol) .......................... Methylamme................................................. Methyl amyl alcohol, see Methyl iso* butyl caromol.............................................. Methyl (n-amyl) ketone (2-Heptanonel ...... C Methyl Bromide-Skin ................................. Methyl butyl ketone, see 2-Mexanone ...... Methyl cellosolve-Skm............................... Methyl cellosoive acetate-Skin ................ C Methyl chloride .................................... Methyl chloroform ....................................... Methylcyclohexane..................................... Methylcyclohexanol ................................... o-Methylcyclohexanone-Skin ..................... Methyl ethyl ketone (MEK), see 2-Butan- one................................................................ Methyl formate.............................................. Methyl iodide - Skin .. Methyl isobutyl carbmol-Skin .................. Methyl isobutyl ketone, see Hexone......... Methyl isocyanate - Skin ......................... **C Methyl mercaptan........................................... Methyl methacrylate.................................... Methyl propyl ketone, see 2-Pentanone.... C aMethyi styrene............................................ C Methylene bisphenyl isocyanate {MOI}..... Methylene chloride (dichloromethane) ....... Molybdenum (soluble compounds) .............. (insoluble compounds).......... Monomethyl anilme-Skin.............................. C Monomethyl hydrazine* Skin......................... Motpnoline-Sktn.......... .................................. * Naphtha {coal tan........................................ Napthalene.................................................... (3-Naphthylamine.......................................... Nickel carbonyl............................................ Nickel, metal and soluble compounds....... 0) jb) ppm Mg M - 0.025 1.000 1.300 -IS - 15 0.25 1 -5 - 0.1 - 0.01 25 100 - 15 20C 61Q i.000 1.650 1.000 10 1. 000 200 10 1.8C0 35 3.10C 260 12 100 465 20 80 25 80 25 120 100 210 350 1.900 500 2.000 100 470 100 460 100 250 5 28 25 100 0.02 0.05 10 20 100 410 100 480 0.02 0.2 S00 1,740 -5 - 15 29 0.2 0.35 20 70 100 400 10 50 - A2 0.001 0.007 -1 * See Notice of Intended Changes 10 Substance Nicotine-Skm............................................. Nitric acid...................................................... * Nitric oxide................................................... p-Nitroamime-Skin ..................................... Nitiobenzene-Skin ....................................... p-Nitrochloro-benzene-Skin......................... Nitroetnane... C Nitrogen dioxide ......................................... Nitrogen trifluonde...................................... C Nitroglycerin-Skin........................................ Nitromethane ............................ 1-Nitiopropane............................................. 2-Nitropropane ........................................... N-Nitrosooimethyl-amine (Di-methylnitrosoammei-Skin...................... Nitrotoluene-Skin.......................................... Nitrotnchloromethane. see Chlorcpictin .... * Octachloronaphthalene - Skin................... Octane............................................................ Oil mist (mineral)......................................... Osmium tetroxide.......................... ............... Oxalic acid.................................................... Oxygen difluoride.......................................... Ozone ........................................................... * Paraquat - Skin............................................ Parathion-Skin............................... ............... Pentabotane................................. ................ Pentachloronaphthalene-Skin...................... Pentachlorophenol-Skin.... .... .................... * Pentane..................................... 2-Pentanone................................................. Perchloroethylene........................................ Perchloiomethyl mercaptan ........................ Perchlotyl fluocide ...................................... Petroleum Distillates (naphtha^................. Phenol-Skin .................................................. p-Phenylene diamine-Skin............................ Phenyl ether (vapor).......................... Phenyl ether-Biphenyl mixture (vapor)....... Phenylethylene, see Styrene...................... * Phenyl gtycidyl ethet (PGE)....................... Phenylhydrazine-Skin.................................. Phosdrim (Mevmphos)-Skin....................... Phosgene (carbonyl chloride) .................... Phosphine...................................................... Phosphoric acid....................... Phosphorus (yellow)..................................... Phosphotus pentachlonde ................. Phosphorus pentasulfide ........................... Phosphorus trichloride................................ Phthalic anhydride........................................ Picric acid-Skin............................................ Pival^(2*Pivalyl*l, 3*indandione)............... Platinum (Soluble Salts).............................. Polytettafluotoelhyiene decomposition products ..................................................... * 1968 Addition 11 a) b) ppm M$'MJ -- 2 25 1 1 100 5 10 0.2 100 25 25 0.5 5 30 6 5 i 310 9 29 2 250 90 90 - A3 5 30 - 0.1 500 2 . 350 --5 - 0.002 - 1. 0.05 0.1 0.1 0.2 - 0.5 -- 0.1 0.005 0.01 - 0.5 - 0.5 1,000 2.950 200 700 100 670 0.1 0.8 3 13.5 500 2.000 5 19 -- 0.1 17 17 10 5 0.1 0.3 - -- 0.5 2 - -- 60 22 0.1 0.4 0.4 1 0.1 1 1 3 12 O-l 0.1 0.002 - A4 / TX TINER RMCO042494 Substance products.............................. .................... ..... Propane............................. ........................... fjPropiolactone . .. n-Propyl acetate ............ Propyl alcohol............................................. n-Propyl nitrate . . .. ... . Propylene oichlonde . . Propylene imme Skin............................... Propylene oxide Propyne, see Methylacetylene ............. Pyrethrum ..................................... PynOrne Qumone ........ Rhodium. Metal fume and dusts ............... Soluble salts ......................................... * Ronnel........................................................... Rotenone tcommercial) ................ ............... Selenium compounds (as $e>....................... . Selenium hexafluoride......................... ...... Silver, metal and soluble compounds......... Sodium fluoroacetate (1080) Skin........... Sodium hydroxide........................................ Strbine ................................................. ...... * Stoddard solvent........................................... Strychnine.................................................... **C Styrene monomer (phenylethylenei.............. Sulfur dioxide ........ ............................. Sulfur hexafluoride ................................... Sulfuric acid................................................. Sulfur monochlorrde ................................. Sulfur pentafluoride Sulfuryl fluoride........................................... Systox. see Oemeton................................ 2, 4,5 T ....................................................... Tantalum....................................................... TEDP Skin ................................................. Teflondecomposition products................. Tellurium ..................................................... Tellurium hexafluoride................................ TEPP Skin.................................................. * C Terphenyls.................................................... 1.1.1. 2-Tetrach1oro-2, 2-difluoroethane..... 1.1.2.2-Tetrachloro-l, 2-difluoioethane ... 1.1. 2.2-Tetrachloroethane-Skin....... ...... Tetrachloroethylene, see Perchforoethy- lene ............................................................. Tetrachioromethane. see Carbon tetra- chlonde................................. ...................... * Tettachloronaphthalene - Skin.................. ** Tetraethyl lead (as Pbi-Skin....................... Tetrahydrofuran............................................ Tetramethyl lead (TML) (as Pb)-$kin....... Tetramethyl succinonitrile - Skm............... Tetranitromethane........................................ Tetryl (2,4,6-trinitrophenylmethyinitra- mtne) - Skin ................................................ ** See Notice of Intended Changes 12 o) b) ppm M9. M3 1.000 200 200 25 75 2 100 A 1,800 As 840 500 110 350 5 240 5 5 15 0.1 C. 4 0.1 0.001 15 5 0.2 0.05 0.4 0.01 0.05 2 0.1 0. 5 500 2.900 0.15 100 420 5 13 1.000 6.000 1 16 0 . 02 5 0.25 5 20 10 5 0.2 A4 0.1 0.02 0.2 0.05 19 500 4,170 500 4.170 5 35 200 0.5 1 2 0.075 $90 0.075 3 8 1.5 >' Subttonce Thallium' soluble compound$i - Skm Thitam ....... Tm nnorgamc cmpds. except oxide1 Tin >organic cmpds)................ Titanium dioxide..................... Toluene (toluol > .... C Toluene-2.4-dnsocyanate o-Toiuidrne Skm . Toxaphene. see Chlorinated camphene * Tributyl phosphate..................................... 1.1.1-Tnchloroethane. see Methyl chloro form .................................... 1.1.2-Trichloroethane - Skm .... Trichloroethylene ........................... ... Tnchloromethane. see Chloroform Trichioronaphthalene - Skm. . . 1.2.3-Trichlotoptopane ... . .. 1.1.2-Ttichloro 1.2. 2-trifluoroethane Triethylamme............................................... Trifluoromonobromomethane............ 2, 4.6-Tnmtrophenol see Picric acid . . . 2, 4, 6-Trinitrophenylmethylnitramme. see Tetryl ............................................. Trinitrotoluene - Skin................... . .. Triotthoctesyl phosphate............................ Tnphenyl phosphate................................... Turpentine .................... Uranium (soluble compounds)...................... (insoluble compounds!.................. C Vanadium (VaOs dust!................................. (V2O5 fume)................................ Vinyl benzene, see Styrene.................... C Vinyl chloride .............................................. Vinylcyanide, see Aciylonitrile............... Vinyl toluene............................................ Warfarin......................................................... Xylene ixylol) .............................................. Xylidme Skin............................................. Yttrium........................................................... * Zinc chloride fume........................................ Zinc oxide fume........................... Zirconium compounds (as Zr) ............... o> PPm l, M3 - 200 0.02 5 0.1 5 2 0.1 15 75C C 14 22 -3 10 45 100 535 5 SC 309 1.000 7. 600 25 100 1.000 6,100 - 1.5 - 0.1 -3 100 560 - 0.05 - 0.25 - 0.5 - 0.1 500 1.300 100 480 - 0.1 100 435 5 25 -1 -1 -5 -5 Radioactivity: For permissible concentrations of radio isotopes in air. see U. S. Department of Commerce. National Bureau of Standards. Handbook69, `'Maximum. Permissible Body Burdens and Maximum Permissible Concentrations of Radionuclides in Air and in Water for Occupational Exposure," June 5, 1959. Also, see U. S. Department of Commerce National Bureau of Standards. Handbook 59, ``Permissible Dose from External Sources of Ioniring Radiation, " September 24, 1954, and adden dum of April 15. 1958. 1968 Addition 13 ! TX TINER RMC0042495 MINERAL OUSTS Substance ) m. p. p. c. f. SILICA Crystalline ** Quartz, Threshold Limit calculated from the formula......................... 250 0 `foSiO z " 5 Cristobalite " "" Amorphous, including natural diatomaceous earth........................... Tremolite................ 20 5 SILICATES (less than !" crystalline silica) * Asbestos.... ..................................... Mica.................................................. 5 20 Soapstone ........................................ 20 Talc.................................................. 20 Portland Cement............................... 50 GRAPHITE (natural)......................... 15 `Inert*' or Nuisance Particulates 50 (or 15 mg m3 see Appendix D whichever is the smaller) Conversion factors mppcf x 35.3 = million particles per cubic meter = particles per c. c. e) Millions of particles per cubic foot of air, based on impinger samples counted by light-field technics. f) The percentage of crystalline silica in the formula is the amount determined from air- borne samples, except in those instances in which other methods have been shown to be applicable. See Notice of Intended Changes 14 zs V NOTICE OF INTENOED CHANGES These substances, witn their corresponding values, com prise those for which either a limit has been proposed for the first time, or lor which a chance in the "Recommended'' list in'.; lus been popped. In both cases, the proposed limits should be considered trial limits that will remain m this List me t-r a period -a a: least two vears. Dunne tins time, the prevjouslv Recommended Limit will remain m ei:o< t. It. alter two v>-.irs :i,, evidence ..... .. to liulu Hut questions the appropriateness tlie values herein, tile values will be placed m the "Rec-.mnu-nded" list. D--cumeniai:ui: is .uailaole for each of these substances. Substone* Abate............................................................ 8oron tnbromide............................................ Bromine pentafluonde............................. . * Butyl mercaptan.......................... ................. +C Cadmium oxide fume (as Cd) ................... Camphor......................................................... Chlonne.......................................................... Cyanogen.................. -t-i-C Dichlotoacetylene........................................ C Oiethylene triamine - Skin......................... Oiphenyl amine................. t-- Endosulfan (Thiodan) - Skin.................. r Ethyl meicaptan............... ............................ Fibrous glass................................................ r Heptane......................................................... Indene................................................. Indium and compounds, as la..................... Iron salts, soluble,as Fe............................. e- Methyl isoamyl ketone............. + Methyl mercaptan...................... .................. C Methyl silicate......................... Octane............................................................ + Oil mist (particulate).................................... t- Oil vapors...................................................... i, r+ Pentaerythritoi (tetramethylomethanei...... 1 e Pentane.......................................... ............... <j) b) ppm Mg M> - 15 1.0 0.1 0.5 -- 0.1 2110 0.1 10 - 10 -- 0.1 0.5 -5 500 2.000 10 -- 0.1 -1 100 475 0. S 5400 1.900 - 5^' hl A - 15 500 1,500 o) Parts of vapor or gas per million parts of contaminated oir by volume at 25 0 C and 760 mm. Hg pressure. b) Approximate milligrams of particulate per cubic meter of air. + 1968 Revision ++ 1968 Addition 15 / TX TINER RMC0042496 Substance o) ppm - Petroieu" distillates............................ ...... a6 Propargyi alcohol -Skin............................. 1 ROX - Skin................................................... _ Stoddard Solvent................. 200 Styrene.......................................................... 50 - Tetraethyl eac as Pb> - Skin.................. - - Tetramethyi lead ras Pb - $km.............. - -- Tcmethyi Denzene............................ 2S Tungsten & compouncs. as w Soluble........................................ _ ir.soiuoie........................................ - Uranium, sol. & insol. compounds as U.-- b) M9 m' i, 5 C. ICO > C. 150'* l 5 0.2 NOTICE OF INTENOED CHANGES (CONTINUED: Subttonc* Asbestos 12`;be:s :n length >' . 01 2 mppcf *' Cristobal ite use one-haif the value calculated from the count or mass formulae for quartz. Quartz ilj TLV for resoirable dust in mg mi : m> 5 Respirable Quartz - 2 (2) "Total dust" respirable and r.onresoitabie: 30 mg m3 Ae Quartz - 2 Tiidymite use one-half the value calculated from foimutae for quartz. j) As determined by the membrone filter method of 430 X phase contrast magnification. k) As counted by the stondard impinger, light-field count technique. m) Both concentration and per cent quartz for the application of this limit are to be determined from the fraction posting a size- selector with the following characteristics: Aerodynamic Diameter 'f1' (unit density sphere) <2 2.5 3.5 5.0 10 9e passing selector __________________ 90 75 50 25 0 g) As sampled by method thor does not collect vapors. h) According to analytically determined composition. >) For control of general room oir; biologic monitoring is essential for personnel control. - 1968 Revision 1968 Addition 16 L3 V + 1968 Revision h- 1968 Addition 17 I TX TINER RMC0042497 Appendix A A1 Ben2idine. 5ccuuse of high incidence ot bladder tumors m him. any .xposurc. including akin. is extremely hazardous. A* o-Naphthyiamine. Because w the extremelyhigh incidence ,[ bladder mm n s m workers handling this compound and the inability to v.-mml exposures. J-uaphtliviaimme lias been prohibited bv me State ot Pennsylvania from manutanurv. use and -..ilier activities tliat involve liunun con tact. A3 N-Nitrosodimethylamire. Because ot extremely luahtoxicitv and presumed carcinogenic potential ji tins compound, "itrao? by ai.-y route should not be pernuncd. A-1 Polytetrafluoroethylene' decomposition products.Thermal decomposition of the fluorocarbon chaw m air leads to the formation of oxidized products containing carbon, fluorine and oxygen. Because these products decompose m part by hydrolysis in alkaline solution, they can be quantitatively determined in air as fluoride t>< provide an index of ex posure. No TLV is recommended pending determination o! the toxicity of the products, but air concentrations should be minimal. A'7 -1 Propioloctone. Because of high acute toxicitvanddemonstrated sfctti tumor production in animals, cxitaet by jnv mute should be avoided. g A Gasoline ond/or Petroleum Distillates. The composition ol these materials varies greatly and thus a single TLV for all types of these materials is no longer applicable. In general, the aromatic hydrocarbon content will determine what TLV applies. Consequently the content of benzene, other aromatics and additives should be determined to arrive at the appropriate TLV (Elkms, et al. A.l.H.A.J. 24, 99, 1963). Trade Names; Algoflon. Fluon, Halou, Tetlon. Tetran Appendix B B.l THRESHOLD LIMIT VALUES FOR MIXTURES When two or ante hazardous substances are present, their combined eifect, rather than that of either individually, should be vtivcn primary consideration. In the absence of information ;' the contrary, the effects of the different hazards should be considered as additive. That is. if the sum of the following fractious. exceeds unity, then the threshold lini:t of the mixture s'i >.:Ul >. , nsidered as being exceeded. Cj indicates the observed .nines* pin-no concentration, and T me oom.sp<mdiug threshold limit. -.Sc-1 Example lA.a.j. Exceptions to the above rule mnv be made when there is good rvas.in to believe that the chut etiwts of tin. duu-rwit harmiul substances are not m fact additive. liut independent as wiku purely local eiiects on different organs oi tin .uv- ; I' -docvil by the various components of the mixture. In such cases tin threshold limit ordinarily is exceeded onlv wtn-n at least-me iw-mber of the senes iCi . C etc.; itsell has a value e-.xTT'01 * T 2 ceedmg unity, tSee Example lA.b) Antagonistic action or potentiation mar occur with some com binations of atmospheric comani.uants. Such cases at present must be determined individually. Potentiating or antagonistic agents are not necessarily harmful bv themselves. Potentiating effects of exposure to such agents by mutes other man that ! inhalation is also possible, e.g. imbibed alcohol and inhaled narcotic ttrichloroethylene). Potentiation is characteristically exhibited at high concentrations, less probably at low. When a given operation or process characteristically emits a number of harmful dusts, fumes, vapors or gases, it will frequently be only feasible to attempt to evaluate the hazard by measurement of a single substance. In such cases, the threshold limit used for this substance should be reduced bv a suitable factor, the magnitude oi which will depend on the number, toxicity and relative quantity of the other contaminants ordinarily present. Examples of processes which are typically associated with two or more harmful atmospheric contaminants are welding, automobile repair, blasting, painting, lacquering, certain foundry operations, diesel exhausts, etc. (Example 2.) 19 ----WJ --T"*- TX TINER RMC0042498 THRESHOLD LIMIT VALUES FOR MIXTURES EXAMPLES 1A. Genera! case, where air is analyzed for each component. a. AOOITIV6 EFFECTS Ci . Cz Ti Tz Ca Ta Cs j Ts Air contains 5 ppm of carbon tetrachloride (TLV, 10', 20 ppm of ethylene bichloride (TLV, 50) and 10 ppm of ethylene dibro mide, (TLV. 25). S 20 10 __ 10 * 50 ' 25 ~ 65 _ j3 50 Threshold limit is exceeded. b. INOEPENOENT EFFECTS Air contains 0.15 mg, ma of lead rTLV, 0.2) and 0.7 mg/in 3 of sulfuric acid (TLV, ll. 0.15 _ 0.20 0.75' 0-7-- = 0.7 1 Threshold limit is not exceeded. IB. Special case when source of contaminant is a mixture and atmospheric composition is assumed similar to that of original material, i. e. vapor pressure of each component is the same at the observed temperature. a. aOOITIVE EFFECTS, approximate solution. 1. A mixture of equal parts (1) trichloro ethylene rTLV, 100), and (2) methyl chloroform (TLV, 350). Ci + Cs _ Cm 100 3S0 Tm Solution applicable to "spot" solvent mixture usage, where all or neatly all, solvent evap- orates. C i = Cz = -i- Cm Ci + Ci 100 3 50 JCj Tm ZCj. JC_L _ 2C i 700 700 Tm Tm = 700 -L = 155 pom lB.b. General Exact Solution for Mixtures of N Components With Additive Effects and Different Vapor Pressures. ID S+ Ti Cz_ + Tz . + Ts = 1 (2) C- r Cz r.. . f Cs = T (2.1) -T- + -T-+- +^= i. By the Law of Partial Pressures, (3) C = apt, And by Raoult*s Law, (4) pi = Fi pi. Combine (3) and (4) to obtain (5) C i = aF ipt. Combming(l). (2,1) and(5), we obtain (6, _LiL+_Eiil+ . . . + _Ll^ = Ti Tz and solving for T, F~sP* + T. Fipi , Fzoz tT + Tz or k=- F ip l M- II II o-- T= 1 =1 F 1 p l Ti T = Threshold Limit Value m ppm. C = Vapor concentration in ppm. p = Vapor pressure of component in solution. 21 I TX TINER RMC0042499 p = Vapor pressure ol pure component F = Mol traction ol component m solution. a = A constant of proportionality. Subscripts 1,2, . . . n relate tne above quantities to components 1,2, . . . n. respectively. Subscript refers to an arbitrary component from 1 to n. Absence of subscript relates tbe quantity to tbe mixture. Solution to be applied wnen there is a reservoir of the solvent mixture whose composition does not change appreciably by evaporation. Exact Arithmetic Solution of Specific Mixture Mol. wt. Oensity T paat Mol frac* 25C tion in half-and half solu* tion by volume Trichloro ethylene (1) 131.4 1. 46 g/ml 100 73mm Hg 0.527 Methylchloroform (2) 133.42 1.33 g'ml 350 125mm Hg 0.473 F i p i* = (0. S27) (73) = 38. 2 Fzp zc = (0. <72) (125) = 59. 2 T_ 38.2 + 59.2 _ 197,4) (350) _ (97.4) /3S0) _ 38.2 , 59.2 133.8 - 59.2 193.0 100 350 T = 177 ppm (Note difference in T. L. V. when account is taken of vapor pressure and mol fraction in comparison with above example where such account is not taken). 2. A mixture of one part of (1) parathion (TLV, 0.1) and two parts of (2) EPN (TLV, 0. 5). 22 T-vvgw -Cl Ci __ Cm: C 2 0. 1 0.5 - Tm Cm = 3C 1 -C`_ | 2C i _ 30 0.1 0. S -- Tm 7C i = 3C i 0.5 Tm 2Ci T" = = 0.2) m9/m3 1C. T. L. V. (oi Mixtures of Mineral Ousts. For mixtures of biologically active mineral dusts the general formula for mixtures may be used. With the exception of asbestos. Pure minerals are assigned TLV of 2. 5, 20 or 50. For a mixture containing 80% talc and 20% iartz, the'TLV for 100% of the mixture "C" is given by: TLV = oXHSl = 20 ' 2.S Essentially the same result will be obtained if the limit of the more (most) toxic component is used provided the effects are additive. In the above example the limit for 20% quartz is 10 mppcf. For another mixture of 25% quartz 25% amorphous silica and 50% talc: ,uv~ Os~~o:2T~o.'5==7-3mopc( 27s r 20 + 20 The limit for 25% quartz approximates 8 mppcf. 23 ! TX TINER RMC0042500 Appendix C BASES FOR ASSIGNING LIMITING "C" VALUES By definition in the Preface, a listed value bear ing a "C" designation refers to 'ceiimg' value that should not be exceeded; all values should fluctuate below the listed value, In general the bases for assigning or not assigning a "C" value rest on whether excursions of concentration above a proposed limit for periods up to 15 minutes may result in ai intolerable irritation, b) chronic, or irreversible tissue change, or c) narcosis of sufficient degree to increase accident proneness.impair seif rescue or materially reduce work efficiency. In order for theCommittee to decide whether a sub stance is acandidate 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. o. c, given above. For this the factors given m 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.l.V. RANGE ppm* or mf/mJ Test T.l.V. Factor Eiample* 0 to 1 1 + to 10 3 Toluene diisocyanate-T. L. V., 0.02 ppm. if permitted to rise above 0.06 ppm may result in sensitization in a single sub sequent exposuie.' "C" listing recommended on category b. 2 Manganese -T.L.V., 5mg/m3, contains little or no safety factor. All values should fluct uate below 5mg/m\ "C" listing recommended on category b. 24 [ V' T.l.V. Test RANGE T.l.V. ppm* or rn|/m) Factor 10+ to 100 1.5 100+ to 1000 1.25 Eiamplts Methyl styrene-T. L. V. 100 if encountered at levels of 150 ppm will prove intense ly irritating, "C" listing recommended on category a. Methyl chlotoform-T. L. V. 350ppm, at 438 ppm for per iods not exceeding 15 min utes is not expected to re sult in untoward effects relating to category c. No "C" listing recommended. * Whichever unit is applicable PERMISSIBLE EXCURSIONS FOR TIMEWEIGHTED AVERAGE (TWA) LIMITS As stated in the preface, the same factors may be used as guides for reasonable excursions above the limit for substan ces to which the time-weighted average applies. The timeweighted average implies that each excursion above the limit is compensated by a comparable excursion below the limit. Thus, a value of 6 -ppm HF is permissible for periods not ex ceeding 15 minutes, provided an equivalent decrease below the limit of 3 -ppm obtains. Appendix D Some "Inert" or Nuisance Particulates* Alundum (AI2O3) Limestone Calcium carbonate Magnesite Cellulose Marble Portland Cement Pentaerythritol Corundum (AUOa) Plaster of Paris Emery Rouge Glycerine Mist Silicon Carbide Graphite (synthetic) Starch Gypsum Sucrose Vegetable oil mists Tin Oxide (except castot, cashew nut, or similar irritant Titanium Dioxide oils) When toxic impurities are not present. 25 TX TINER RMC0042501 Appendix E Some Simple Asphyxiants - "Inert" Gases and Vapors. Acetylene Argon Ethane Ethylene Helium Hydrogen Methane Neon Nitrogen Nitrous Oxide Propane EJ. Baier Hervey B. Elkins. Ph.D. W.W. Fredrick, Ph.D. Bernard Grabois, P.E. Paul Gross, M.D. Way I and J. Hayes,Jr., M.D. Harold N. MacFarland, Ph.D. Consultant Fredrick T. McDermott E. Mastromatteo, M.D. Walter W. Melvin, M.D. Ralph G. Smith, Ph.D. Mitchell R. Zavon, M.D. Herbert E. Stokinger, Ph.D., Chairman William D. Wagner, Recording Sec*y 26 27 i TX TINER RMC0042502 ; TX TINER RMC0042503