I
in the Chemical f aboratory Edited by N O R M A N V . STEERE, School o f Public Health, University o f Minnesota, Minneapolis, Minn., 55455
...a
4aD
feature
values in sssessing the health hazards which may be associated with expoellre to mixtures of two or more substances. A Prepared by The American Conferenre of (hverrtrnental brief disct~ssionof basic eousiderations inIndustrial Hygienists.' volved in developing threshold limit values for mixtures, m d methods for their development, amplified by specific examples Documentation. A separate companion The T h ~ s h o l dLimit Values refer to airare given in Appendix B. piece to the Threshold LimiL Valnes is isborne concentrations of sobst,ances and "Inerl" or Nuhanee Particulates. A sued by The American Conferenre of represent conditions under which i t is Governmentd Industrid Hygienists ~ ~ n d e r number of dust,s or particulates that uccltr believed that nearly all workers may be in the warking environment ordinarily this title. This publication gives the repeatedly exposed, day after day, without produce ,no specific effects upon pmlanged pertinent scientifio information a t ~ ddata adverse effeet. Because of wide variat,ion inhalation. Some insoluble snbstances ale literature sources that were used to base in individual stlsceptihility, expoare of an clilssed as inert (e.g., iwn and st,eel dusts, each limit. Each doc~tmentatiunalso conocca~ionalindividual a1 or even helow the cement, silicon cnrhide, titanium dioxidc, tains a statement defining the type of 1.ethreshold limit, may not prevent discomcelh~lose); o t h e ~ smay he soluhle (st,weh, sponxe against whivh the limit, is safefort, sggravet,ion of a preexisting eondisoluble oils, calcium carbonate) hut are of guarding the worker. For a. better undertion, 01. occupational illness. such a low order of activity that in concenstanding of the TLVs it is essential thnl the Threshold limits shonld he used as trations odinarily encountered do not Documentation he consulted when the gtrides in the control of health hazwds and cause physir,hgic impairment; still others TLVs are being used. should not, be regarded as fine lines bemay he rapidly eliminated or destroyed hy tween safe aud dangerow coneentrat,ions. Ceiling vs Time-Weighled Aueregr Limits. the body (vegetable oils, glycerine, suExceptions are t,he substances given in Although the rime-weighted average conemse). I n the ca.e of the i~tmlnblesubAppendix A and certain of the subcentratinn provides the most, satisfactory, stances, !here may he some neci~mr~lation stances given a. "C" listing. The values pract.i.ieal way of monitoring nil-home in the respimtor,~passages. In the case not given a "C" listing refer to timeagentsfor compliance with thelimils, there of the solilhle s,thstnnees, this aec,md;tweighted average .eeoneenbrstiansfur a norare certain suhstanees for nhirh it is intion will ordinail" be temporary hut may mal workday. The amount by which appropriate. In the latter grotlp a1.e subintwfere to some extent with iripiratcwy these concentrat,ions may be exceeded for stnnees which are predominantly fast aetpmresses. Hence, it is desirnhle t,o contrul short periods without injury to health deing and whose thteshold limit is more the etmce~tt~~atinrrs of such pal.tirulst,es in pends upon s number of factors such as t,he appropriately based on this palticulat. rethe ail. hwiithed hy any individnal, in keepnature of the contaminant, whether very sponse. Snhstalices with this type or re ing with good i~tdnstrialhygiene practice. high concentrations even for short periods sponse are best colttrolled by a ceiling "C" A threshold limit of 15 mg/rn3, or 60 pluduce acute poisoning, whether the limit thnt should not he exceeded. I t is mppef, whichever is less, is recomrnencled effert,s are cumdative, the frequency with implicit in t,hese definitions that the ma]!for sithstanees in these categories and fov which high coneentratio~tsoccur, a ~ the d ner of sampling to determine compliance which nu specific threshold limits have duration of such periods. All must he with the limits for each group must diRer; been assiglled. This limit, for a normal taken into mnsiderat,ion in aniving a t a a single brief sample, that is xpplicablo lo work day, does not apply to brief erpoiiures decision RS to whether a hasxldons situa"C" limit, is not appropriate to the timea t higher cnnrentratiuns, Neither does it, tion exists. Enlightened industrial hyweighted limit; here, asuHicient uumherof apply to those srrbstances which may cause giene practice inclines toward eont,tdling samples are needed to pelmit a timephysiologic: impairment a t lower cnncew exp,sures below the limit rather than weighted average conceltlratinu thnmghtrations hnt for which a. threshold limit, maintenance a t the limit,. wt a. complete cycle of uperationx or has nut yet been adopted. Some "inert" Th~.esholdlimits are b a d on the best throughout the work shift. particulates are given in Appendix 1). available information fmm industrial exWhereas the ceiling limit places a Simple Asphyziant,-"Inerl" Gares or perience, from experimental human and definite boundary which concentrations Vapors. A number of gases and vapors, animal studies, and when possible, f n m a should not be permitted to exceed, the time when presenL in high concentrations i l l air, combination of t,he three. The basis on weighted average limit requires an explicit act primarily as simple nsphyrianta wit,hwhich the values are established may differ limit to the excwsions that are permissible out other significant physiologic effects. f ~ n msubstance to whstnnce; protection above the listed values. The magnitude A TLV may not be recommended f a r each against impairment of health may be the of these enenrsions may be pegged Lo the simple asphyxiant hecause the limiting guiding fsrbur for some, whereas reasonmagnitude of the thveshold limit hy an factor is the nvailahle oxygen. The able freedom from irritation, narcosis, appropriate factor shown in Appeudix C. minimal oxygen content should he 18% hy nuisance, ar other forms oi stress may I t should be noted that t,he same factow are vohme tlnder normal at,mosphet.icpress,~re dominate the baiis for othem. The Com!wed by the Committee in making a judg(equivalel~tto an oxygen partial pressure, mittee holds t,o the opinion that limits ment whether to include or exclude r. snbof 135 mm Hg). Atmospheres defir.ient b a x d on physical irritation should he eonstance for "C" listing. in O2do 1101prvvide a d e q u ~ t ew a ~ . t ~ iBl ~I gI ~ sidered no less binding than those based on Skin Nolalion. Listed s,lbstanees f o most simple asphyxiants are a d d e a r . physical impairment,; growing bodies of lowed by the designation "Skin" refer to Several simple asphyxiants are lirtod in evidence indicate that physical irritation the potential conlribntion to the overall Appendix E. Rome asphyxiants present may ptumote and acaelerate physical imexposure by the cutaneons mute iuelnding an explosion hnnard. Account shonld be pairment.. mucous membranes and eye, eit,her hy airtaken of this factm in limiting the concenhome, or more particularly, by direct cuntration of the aqhyxiant. 1 Tl!rerhold Limit Committee of the American Conference of Oovernmeotsl Industrial Hymentact with the substance. Vehicles can These limits are intended for use ill the iatr: E. .I. nsier: Allan L. Coleman: Hervey H. alter skin abswption. This aatentionfield of indnstrial hygiene and shnnld he Elkins, Ph.I>.: \I7. 0. F~edriok.1'h.D.: Bernard b I . : I'aal Gross, M . D . : \Yaylnnd J. calling designation is intended to suggest interpreted and applied only h y persons Hayes. .lr.. M.D.: Harold N. MaoFarlhnd. Pb.D.. appmpriste messures for bhe preventiwr of trained in this field. They are not inronsultant; E. Masiromalteo, M . L . ; Russel G. Srurill: R d p h G . Smith, Pbll.; G e o r ~ eW. mtaneous absorpbion so thnt the threshold tended for use, or for modification for use, \Vrizl>t.M.11.. Consultant: Mitchell R. Zavon. limit is not invalidated. (1)as a relative index of toxicity, by mak3 l . l ~ ;nerlwt E. Stokinper, Ph.lI.. Chairman. ing a ratio of two limits, (2) in the e v a h ~ a dlizlures. Special consideration should (Continued on. page A481 he given also to the application of these *Reprinted with permission.
XXXIII. Threshold Limit Values for 1966*
Volume 44, Number I , January 1967
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A45
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tion or control of community air pollution or air pollution m~issnees,(3) in estimating the toxic potential uf continuous uninterrupted exposures, (4) as proof or disproof of an existing disease of physical condition, or (5) for adoption by conntries whose working conditions differ f m m those in the U.S. Physical Factors. I t is recognized that such physical factors as heat,, ult,raviolet and ionizing radiation, humidity. abnormal pressure, and the like may place added stress on the hady so that the effects f m m exposure a t n threshold limit may be altered. Most of these stresses act adversely lo increme the toxic response of a substance. Although must threshold limits have built-in safety factors to guard against adverse effects of moderate deviationsfrum normal environments, the safety f s e t o n of most substances are not of such a magnihde as t o take care of gross deviations. For example, continuous work a t temperatures above 90°F or overtime, extending the work-week more then SO0i,, might he eonsidered gmss deviatians. 111 such instances judgment must be exercised in the proper adjustments of the threshold limit vah~es. These values are reviewed annually by the Committee on Threshold Limb for revision or additions, as fllrther information becomes available.
Notice of Inlent. At the heginning of each year, pmposed actions of the Committee for t,he fort,hcoming year are issued This in the form of a "Noticeof Intent." notice provides not only itn opportnnit,y for comment, hot salicit,~suggestions of substances to be added to the list,. The suggestions should he accompanied by substantiating evidence for a tent,ative limit. Legislative Code. The Conference does not consider the Threshold Limit Vnlries appropriate matte]. for adoption in legislative codes and regdations, and reeommends against such use. If, however, the list is so used, the intent of the concepts contained in the Preface should be maintained and provisions should he made to keep t,helist current. Reprint Pe~mission. The pamphlet "Threshold Limit Values for 11166'' may be reprinted provided that writlen permission is oht,ained from the SewetaryTreawrer of the Conference and that i t be published in its entirety. Tentative Values. Snbstances for which a T or tentative value is shown comprise those for which a limit ha- been &-signed for the fimt time or far whieh a change in the "Recommended" listing h a been made. I n both cases, the assigned limik should be eonsidered trial values that will remain in the tentative listing for a period of a t least two years, during which time definitive evidence and experience is sought. If acceptable s t the end of two years, these subst,ances and values will be moved to the recommended list. Documentation for tentative values are available for each of these substances.
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Journal o f Chemical Education
1966 Threshold Limit Valuer \.dues are timeweighted averages unless indicated as "Ceiling" by "C." The numbers are TLV in ppm (of vapor or gss in air plus vapor by volume a t 25% and 760 mm Hg); The numbers in perentheses ( ) are TLV in mg/Ma (approximate milligrams o f particulate per cubic meter of air). "Skin" indicates skin penetration. acetio a e B o e t i c anhydride Acetone Aoetonitrile Acetylene tetrabromide See 1.1.2.2-Tetrshromoethane Aorolein Aoryismide Aorylonitrile blArin
AIGI
Allyl glycidyl ether Allyl ~ r o ~ disulfide y l Alundum (See Aooendix D) 2-Aminop&dine Ammonia Ammonium Sulfamate (Ammate) n-Amyi acetate Pentyl zoetate) set-Amyl&eetate n-Amyl alcohol (See Pentul aloohol) eeo-Amyl alcohol (See 2-Pentanol) 1-Amy1 aloohol (See t-Pentyl alcohol) Aniline 0-Anisidine pAni8idine Antimony and ~ o m p a u n d s(as
was
0 . 1 (0.25) (0.3) T Skin 20 (45) Skin (0.25) Skin
2 (5) Skin 1 (3) C 1 0 (45) 2 (12) 0 . 5 (2) T 50 (35) (15) 125 (850) T
5 (19) Skin (0.5) Skin (0.5) Skin
Sh,
~ i i l l u(I-(I-NaphthyU-2-
thiourea) Arsenio a n d compounds (as
ae
~~~,
Arsine Arinphos-methyl (Guthion) Bsrium (soluble oomoounds) Bentonite (Sac Appendix D) Benneoe (Benaol) Benaidioe (See A ~ ~ e n d A) ix Benrovl oeroxide B e n d chloride (Sac Toiuenethiol) Berylhum Bis (dimethylthiooarbamoyl) diaulhde (Thireml Boron oxid; Boron trifluoride Rromine Bmmoohloromethhne Bromoethane (ethyl bmmide) Bromoform 13romomethsne (methyl bromide) Bromotrifluoromethaoe (Trifluommonohromoethane) l,bButadiene I-Butanelhi01 (n-Butyl mereaptan) 2-Butanone (Methyl ethyl ketone) 2-Butoxvethanol n-Butyiwetate seo-Butylhcetate terl-Butylaeetate n-Butyl alcohol See-Batvl hlonhol
(0.5) 0 . 0 5 (0.2) (0.2) T Skin (0.5) C 25 (80) Skin
(5) (15) C 1 (3) 0 . 1 (0.7) 200 (1050) C 200 (890) 0 . 5 (5) T Skin
200 (590) 50 (240) Skin 150 (710) T 200 (950) T 200 (950) T 100 (300) 150 14501 T 100 boo) C 5 (15) Skin
Ckrbon dioxide Carbon diaulfide Carbon monoxide Carbon tetrachloride Cellulose (See Appendix D) Portland Cement (Sea Appendix D) Chlorbenrylidene malonitrile (OCBM) Chlordane Chlorinated oamphene (Torsphene) Chiormated diphenyl oxide Chlorine Chlorine dioxide Chlorine trifluoride Chloroaoetaldehyde d2hloroaoeto henone (phenaoyloh%ride) Chlorobenrene 0-Chlorobenz lidene malononitrire (OCBhl) Chlorobromomethsne Chlorodiphenyl (42% chlorine) Chlorodiphenyl (54% chlorine) Chioroetllane 2-Chioroethsnol (ethylene ohlorohydrinl Chloro?thylene (Vinyl ohlorrde) Chloroform Chloromethsne (Methylohloridel p-Cllioronitrobenee"e 1-Cl~Io1o-l-nitr0~1o~aae Chluropierin See Trichloronitmmethanr Chloroprene (2-ohloro-1,3butadiene) Chromio w i d a n d chrometes (as CrOd Coal t a r pitch volatiles , (Benrene soluble fraotmn) (Anthrscene, ESP. ~henxnthrene,p or id one ehrysene, pyrene) Cobalt Conoer fume Cobber durn and mists Corundum (AhOz) (See Appendix D) Cotton dust (raw) C m m Herbicide mCreso1 eCresol p-Cresol Cmtonhldehvde Cumene Cyanides (as CN) Cyelolieltane Cyoiohexand Cvoloheranone C;olohexene Cyolo~entadiene 2,4D(2,4-Diohlomphennn~acetic aoid) D D T (2.2-bis (pohlorophenv1)-1.1.1triehloroethane) D D V P (0.0-Dimethyl-2.2diohiorovmvl ohmohate)
5000 (9000) 20 (60) Skin 50 (55) T 10 (65) Skio
0 . 5 (0.4) T (0.5) Skin (0.5) Skin (0.5) C 1 (3) T 0 . 1 (0.3) C 0 1 (0.4) C 1 (3) 0.05 (0.3) T 75 (350) 0.5r (0.4) T 200 (1050) (1) Skin (0.5) Skio 1000 (2600) 5 (16) Skln C 500 (1300) C 50 (240) C 100 (210) (1) T Skin 20 (1001
25 (90) Skin (0.1)
(0.2) T (0.5) (0.1) (1.0) (1) (15) 5 (22) Ski" 5 (22) Ski" 5 (22) Ski" 2 (6) T 50 (245) T Skin (5) Skin 300 (1050) T 50 (200) 50 (200) 300 (1015) T 75 (200)
(1) Skin (1) Ski" 0 . 0 5 (0.3) Skin (0.1) Skin
C 25 (190) T Skin C (0.1) Skin 50 (270) P-(1-Butyl)-toluene Cadmium oxide fume Cadmium (metal dust and a d . Calcium carbonate (See Appendix D) Caioinm oxide Camphor Carbarvl (Sevine) Carbon black
1 0 (60) (0.1) (0.2) T (1)
hydantonin I 1-Diohloroethana l:2-~iohloroethane(ethylene diohloride) 1.2-Diohloroethylene Diohloroethyl ether Diohlommethane (Methylene ohloride)
50 (200) 200 (790) C 15 (90) Skin
(Continued a page A48) Volume 44, Number
I , lanuory 1967
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A47
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(2.4-U)
Dirliiorotetrafluoroethane Dieldrin Diethvlamine Diethblsmino ethhnol Diethyl ciher Difloorodibromomethhne Digly~itl~ ether l (DGE) Diirobotyl ketone Diiso~ropylamine N,S-Dimethyl aeetamide Dimetlrylhmine Dimethybniline Dimethjl I.Z-dihromo-2.2dichloroethyl phowhate (Dihroml NN-Uimethvlformamide
G'?:?
. .
Dipropylene glycol methyl ether Ernerx (Sas Appendix D) Endrln Epiehlomhydrin
-. .. Ethanethiol (ethyl mereaptan) VDkT
Etllanolamine 2-Ethoryethaool 2-Ethoryetliylaeetste (CelluaolveE aeetste) Ethyl hoelste Ethyl acryiate Etilyl alcohol Elhylsrnine Ethyl Sec-amyl ketone (5 methyl-3-heptaoone) Ethyl benrene ELhyl bromide (See Rrumoethand Ethyl butyl ketone (See Hexanone) Eth>-I ohloride (See Chloroethane) E t h y l ohlorohydrin (See 2-Chloroethaool) Ethylmediamine Ethylene glycol dinitrate Ethyiene imine Ethylene oxide Ethyl formate Ethyl m e r o h ~ t h n (See Ethanethiol) N.Eth3.1 morpholine Ethyl silicate Ferbhm (Uimethyldithiooarbamiceoid) Ferruranadlum dust Fillon
!%
(7000) (0.25) Skin 25 (i51 10 (50) T Skin 400 11200) 100 (860) C 0 . 5 (2.8) 50 (290) 5 (20) T Skin Skin
:,"
5 (251
8 ( 3 0 1 Skin 0 . 5 (11 Skin (5) T 1 (5) s k i n (1) Ski" (I) Ski* (1) Skin (0.2) Skin (l..51 Skin (1.5) Skin 15) 100 (360) Skin 0.2 (I) T 100 (600) Skin
100 (540) Skin 400 (14001 25 (1001 Skm lono (1900) 10 (181 T
10 (25) C 0.2 (1.2) Skin 0.6 (1) T Skm 50 (90) 100 (300)
Gasoline
(0.51 Skin 500 (2000) 100 (465) T 50 (230) T
1,2.3,4.5.6-Hera~hIomc~~Iohexane
Lindane) Hexsehloroethane Herac1,Ioronsphthalenene n-Herane Hexsnone (methyl butyl ketone) (See
A48
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1 (10) Skin (0.2) T Skin 500 (1800)
Journal of Chemical Education
100 (410) 50 (300) T I (1.a) skirn 3 (101 C 5 (i1 10 (111 Skin 3 (21 Skin l(1.41 0 . 0 5 10.2) 10 (151 (2) C O I (1) 5 (28) T Skin
$3
$25) T 100 (360) 110 (7001 T 100 (300) T 25 (140) 250 (950) T 1soi,rowi acetate 100 (980) Isopropyl alcohol 5 (12) 1soprupy1amine 500 ( 2 , l a o ) IsoprowI ether I s o p r ~ p y l g l y ~ i dether yl (ICE) 50 (210) 0 5 (0.9) Iietene (0.2) Lead (0.15) Lead arsenate Limestone (See appendix D) Lindsne (1.2,3.4,5,6-Hexa(0.5) Ski" ohloroeyelohexane (0.025) Lithium hydride 1000 (1800) Liquid petroleum gas (L.P.G.) Maenesite (See Appe"dix D) Magnesium oxnle fnme Melathion Malei0 anhydride Lwaneanese hlarble (See Appendix D) (0.011 Ski" h1emnry ~ e s i t y oxide l (See 4-Alethvl-3-oenten2-one) hlethanethiol (Methyl rneroaptanl Methanol (Methyl alcohol) Methoxyehlor 2-Methoxjethsnol 2-A1ethuxsethanol acetate Methyl metate Methyl aoetvlene (See Propsne) 10 135) Skin Methyl aerylnte Methyial (dimethorymethane) 1000 (31001 nIeihyl a ~ c o h o ~ (See Methanol) l o (12) T Methylamine Methyl n-smyl ketone (See P~FleptanoneI 2 (91 Skin N-Methyl aniline hlelhyl bromide (See llromomethane) Methyi Cellosolue@ (See 2-Alethoxpethhnol) Methyl Cellusolre~Sm e t a t e (Sce 2-Alethoryethanul
.
(0.1) Ski" 5 (19) skin (0.5) C 10 (25) 3 (81 200 (7401 Skin
(See Apoendir D) Fluoride (as P) Flnorins Fluomf richloromethane (See Trichlorofluoromethane) Formaldehyde Formic acid 2-Furaldehyde Furlural (See 2-Furaldehyde) Fvrfuryl aleohol Class fibrous ~ l ~ & i rMist ~e , (See Appendlr D) Glyeidol (2.3-Epoxy-1p'opsnol) Gypsum (See Appendix D) Hafnium Halon (Sea Appendix D) Heptsehlor n-Heptane 2-Heptanone (Methyl n-amyl ketone1 3-Hewanone (Ethyl butyl kctonel
Hexone (Methyl isobuty ketone) seo-Hexyl acetate Hydrarine Hydrogen bromide anhydrous Hydrogen chloride Hydrogen cyanide Hydrogen fllloride Hydroxen peroxide, 90% H y d r u ~ e nselenide H y d r o ~ e nsulfide Hydroliuinone lodins Iodomethane (methyl iodide1 I r o n oxide fume 1soamyl acetate Isoarnyl alcohol Isobutylaoeihte Isobotvl alcohol
~
~.
.
hoetste
Methyl chloride (See Clrloromethane) Methyl ehiuraform (Sac 1.l.l-Triohloromethane) Methyleyoioheltane 2-Methyloyoloheranal a-Alethylopoluheranone Methylene bir ohenvlisooranate IMDD Mkihyiene oVloride (See Diehloiomethane) Methyl formate 5-Methyl-3-heptsmone (Ethyl sec amyi ketone) Methyl hydrarine Methyl iodide (See lodomethan?) Methyl irohotyl oarblnal (Methyl amyl alcohol) Methyl iaoojsnate lSee 1soeranio acid. methyierterl Methyl meroaptsn (See \lethanethid) Methyl methacrylate 4-Methyl-3-penten-2-one ol-Methxl styrene (Vinyl toluene) Molybdenum (insoluble oampuunds) hlolrhdenurn lsoluble eomooandsl Morpholine Naphtha (coal tar1 Naphtha (petroleum) Naphthalene 8-NaphfhyI&min~ (See l p p e n d u A) Niokel osrbonyl Niokel metal and eoluble compounds Nicotine Nitrio acid Nitric oxide m-Nitroanilior p-Nitroaniline Nitrobenzene
SO0 (2000) 100 (470) 100 (160) Skin
(m
20 (70) Skin 100 (4001 T 500 (20001 10 (50) 0.001 (0.007) (11 (0.5) Skin 2 (5)
25 (30) T ? 1 (6) Skin 1 (5) Skin
Safety
.. .
pNitmehlorohenraoe (See pChloronitrobenzene1 Nitmethane Nitmgen dioxide Nitrogcn trifluoride Nitmslyoerin-EGDN Nitromethane l-Nitroprowna 2-Nitmprop&ne N-Nitrosodimethylamine (See .A~gendixA1 Nitrotolnene Ootsohlorona~hthalene n-ootsnc Oil mist (minerall Oil mist (veaeiablel (sea Appendix D l Osmium tetraaide O d i o acid O x y ~ e ndinuoride Oxone Parathian Paraquat Pentsborsne Pentaohloronaphthalene Pentaehlomphenol Pontane 2-l'entanol (see-Amy1 alcohol1 3-Pentanol (sea-4myl alcohol1 2-I'eathnone (iMethyl propyl ketone) P e n t r l acetate (n-Amyl acetate) Pentyl aloohol (n-hmyl aleohull Perobloroethslene (Tetraol~loroethylene) Pelcliluromethyl meroaptan Perohlory1 fluoride Phenol Plrenyl ether (vapor1 Phe?yl ethcr-bighenyl m1rture (rapor) Phenvl elveidsl ether (PGE) p-PIreny1eoe dihmioe Phensl hydrailine Phordrin (>lermphos@] , I'hosgene (Cadmnyl ehlonde) Pllosphine Phos~1,orieheid I'horpl~orus (sellowl Phosphorus pentaohloride PhosPhorus pentssulfide Pl~oaplromstriehloride Phthzlio anhydride pierie noid P1"hl I'lhater of Paris (See Appendk D l Platinum (aoluble ssltsl Polytetrafluoroethylene decomposition products (See A ~ p e n d i rA1 Propa"e (gar) 8-Pmplolaetone , wee Aoueodlx A1 n-Pmpyl soPfate n-PmPyl sleohol-? Propy1 e t h e r ? n-Prowl nitmte P r o ~ y l e n edlchloride (1.2-Dioi~Ioropropane) Pmpylene imine Pmpylene oxide Pmuyne Pronyne-umpdiene mixture Pyrethrum Pyridine Quinqne Rhodmm-metal fume and dusts Rhodium-soluble salts Ronnel Rotenone (Commercial) Roore (Sea Appendix D l selenium e o m ~ o u n d s(as Se) Selenium horafluoride Silicon Carbide (See A"pendix D l Silver-duble compounds a n d metal Sodium fluoroseetate (1080) Sodium hydroxide Staroh (See Appendix D l Stilbene Stoddard solrent Stryohnine styrene monomer ( ~ h e n v l etllrlene) Suoroae (See Auuendix D l Sulfur ohloride Sulfur dioxide Sulfur hexanuoride Sulfuric heid Suliur uentafluoride Sulfvryl fluoride 2.4.5 T (Sac Triohlomphenory~ 0 e t 1 acid) 0
100 (3101 C 5 (91 10 (291 C 0.2 (21 Skin 100 (2501 25 (901 25 (90) 5 (301 Skin (0.1) T Skin 500 (23501 (5) (0.0021 (1) T 0 0 5 (0.1) 0.01 (0.21 (0.11 Ski" (0.51 T Skin 0.005 (0.011 (0.5) Skin (0.51 Ski" 1000 (29501 100 (360) 100 (360)
100 (670) 0 . 1 (0.81 3 (13.5) 5 (19) Ski" 1 (71 T 1 (il T 50 (3101 (0.1) Skin 5 (221 Skin (0.1) Skin 0.1 (0.4) 0 . 8 (0.4) (11 (0.11 (11 .1)( 0.0 (31
?&?Skio (0.1) T
(0.01) (0.051 Skin (21
(51 (0.2) Skin Teflon (See Appendix D l Tellurium (0.1) 0.02 (0.21 T Tellurium h e r d u o r i d e T&PP (Tetraethyl pymphosphatel (o.oa) skin 1.1,2.2-Telrabromoethano (loetvlene tetrabromide) 1 (141 1,1.1,2-Tetraohlom-2difluoroethane 500 (41701 5 (35) Skin 1,1.2.2-Tetraehlomethanp 1.1.2.2-Tetraehloro-1.2-diflu~~o 500 (4170) ethBne (2) T Ski" Tetraollloronaphthalene (0.075) Skin Tetraethvl lead (as Pbi 200 (6901 Tetrshpdrofuran Tetramethyl lead (TML)(as Lead) Tetramethyl suooinonitrile Tetrm (See Appendix D) Tetranitromethhne :,"'I Skin Tetryl (0.11 s k i n Thallium Thallium (soluble compounds1 (0.1) Skin Thiram (Sea Bisfdimethvlthiocarba&ovll d&ulfide T i n (inorpanin oompounds) Tin (organic compounds) T i n oxide (See A l l ~ e n d i rDl Titanium dioxide Toluene Toluene2.4-diisooyanste 2-Toluenethiol ( B e n 4 chloride) 1 (51 5 (22) Ski" O-Toloidine 5 m w o f (-1 T Tremolite 350 (1900) 1,l.l-Triehloroethane 10 (45) s k i n T 1.1.2-Triehlomethane 100 (53,51 T~iohloroethylene Triehlorofluoromethaoe (Fluorotriehlorometl?%ne)
Triohlorometl~anethiol (Perchlorometil+ 0 . 1 (0.81 meraevtan) (51 Skin Triohlornnaphthalene Triehloronitromethane 0 . 1 (0.71 (Chloio~iorin) 50 (3001 1.2.3-TrichIoropmp8ne 1.1.2-Triehloro 1.2.21000 f7ROOl trifllloruethsne 25 (100) Trieihylamine Trinoorol,ro,"ometi,*"e (See nromotrifluorometha nel (1.5) Skin Trinitrotoluene Tri-o-creayl phosphate (0.1) Triphenyl phosphate (8) 100 (5601 Turpentine (0.25) Umnim (0.05) Uranium soluhle compounds Ulanirim inroluhle oompounds (0.25) C (0.51 vanadium d i m (V20d C (0.11 Vansdium fume (V?O.I Vinyl chloride (See Chloroethylene) vinyl to1,iene (See Methyl styrene Warfarin (0.11 100 (435) T m-xy1ene 100 (4851 T o-xylene loo (435) T p-xy1ene i, (25) Skin Xglidine yttrium (I1 zinc ohloride (11 Zinc oxide fume (51 Ziroonium oompounds (as Zd (51
Radioaetivag: For permissible concentrations of radioisotopes in air, see U.S. Department of Commerce, National Bureau of Standards, Hnndbook 69, "Maximum Permissible Body Burdens and Maximum Permissihle Concentrations of Radionuclides in Air and in Water for Occup8.tiond Exposure," June 5, 1959. Also, see US. Department of Commerce National Bureau of Standards, Handbook 59, "Permissible Dose from Externd Sources of Ionizing Radiation," Sept. 24, 1954, and addendum of April 15, 1958. RESPIRABLE DUSTS Threshold Limit Values for respirable dusts are evaluated by count. The numbers given are millions of particles per cubic foot of air, bmed on impinger samples counted by lighbfield techniques. (Crmtinued on page A50)
Crystalline Qusrte, Threshold Limit calculated from the formula . . . . . . . . . . . 250** Cristohalite, Threshold Limit calculated from t,he formula.. . . . . . . . % SiO? 5 Amorphous, including natural diatomaceow earth 20 Silicates (less than 17$ wystdline silica) 5 Asbestos. . . . . . . . . . . . . . . 20 Mien. . . . . . . . . . . . . . . . . . Soapstone . . . . . . . . . . . . . . 20 20 Talc. . . . . . . . . . . . . . . . . . . 50 Portland Cement.. . . . . . . Graphite (natural). .. . . . . . . 15 "Inert" or Nuisance Particulates: 50 (or 15 mg/mJ whichever is the smaller) (see Appendix D ) Conversion Factors mppcf X 35.3 = million particles per cubic meter = prtrticles per r.c.
+
**The percentage of crystalline silica in the formula is the amount determined from air-borne samples except in these instances in which other methods have been shown to be applicable.
Appendix A Benzidine. Because of high incidence of bladder tumors in man, any exposure, including skin, is extremely hmtzardous.
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p-Naphthyhmine. Because of the extremely high incidence of bladder tumors in workers handling this eompoond, and the inability to control exposures, B-naphthylamine has been prohibited from manltfacture, me and other activities that involve human contact by the State oi Pennsylvmia. N-Nitrosodimethylan~ine. Becanse of extremely high toxicity and presumed carcinogenic potenbid of this compound, cuntact by any route should not he permitted. PolyletrafluoroethyIpne (Trade Names: Algoflon, Fluon, I-Ialon, Teflon, Tet,ran) decomposition products. Thermal decomposition of the flnoroearbon chain i n air leads to the formation of oxidized pl.oduetn containing carbon, fluorine, and oxygen. Becwse these products decompose by hydrolysis in alkaline solutiorl, they ran he determined in air ai fluoride to provide an index of exposure. No TLV is recommended pending determination of the toxicity of t,he prod~mts, but air concentrations should be minimal. 8 - P ~ o p i o h d n e . Becanse of high acute toxioity and demonstrated skin tumor production in animals, oont,acl by any route should be avoided.
Appendix B Threshold Limit Values for Mixtures When two or more hazardous srtbst,ano~ are present, their combined effect, rather than that of either individuall.~,should he given primary consideration. I n t,he at> senee of information to the cmtrary, the effects of the different hazards shmtld be
considered a3 additive. That is, if the sum of the following fractions,
exceeds unity, then the threshold limit of the mixture should be considered as being exceeded. C , indicates the obsei~edatmospherir concentration, and TIthe corresponding threshold limit (See Example 1A.a.). Exceptions to the above rule may he made when there is good reason to believe that, the chiof effects of the different harmful subst;tlreei are not in fact additive, but independent a-when purely local etfects on ditTerent organs of the body are produced by t,he various cumpaneuts of the mixtwe. I n such cases the threshold limit ordinarily is exceeded only when at leas1 one member of the series ( C I / T , or C2/T2, etc.) itself has a value exceeding unity (See Example 1A.b.). Antagonistic action or potentiat,ion may ocour with some mmbinations of atmospheric contaminants. Such cases a t present must be determined individuall.~. Potentiat,ingor antagonistic agents ace not necessarily harmful by themselves. Potentiat,ing effect.? of exposme to sllch agents by routes other than that of inhalation is also possible, e.g., imbibed alcohol and inhaled narcotic (trichloroebhylene). Potentiation is characteristically exhibited at high concentrations, less probably a t low. When a give,, uperatiall or process chararteristicslly emits n. numher of harmful dnsts, fumes, vapolx, or gases, it will ire-
Safety
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quently be only iea-ible to attempt to evaluste the hazard hy mesurement of a single substance. I n snoh cases, the threshold limit used for bhis substance shonld be reduced by a suitable factor, the magnitude of which will depend on the number, toxicity, and relative quantity of the ot>hercontaminants ordinarily present. Examples of processes which are typically associated with two or more harmful atmospheric contaminants are welding, automobile repair, blasting, painting, lacqueting, certain fonndry operations, diesel exhausts, etc. (Example 2.)
Examples: Threshold Limit Values for Mixtures IA General case, where air is analyzed for each oomponent. ( a ) Additive Efect'eds
Air contains .5 ppm oi carbon tetrachloride (TLV, lo), 20 ppm of ethylene dichloride (TLV, ZO), and 10 ppm of et,hylene dibromide (TL\', 25).
Threshold limit is exceeded i h ) I n d e p a d a t EJecteelr Air contains 0.16 mg/l\13 of lead (TLV, 0.2) and 0.7 mg/Ma of sdfuric acid (TLV, 1).
Threshold limit is not exceeded. 1B Special case when source of contaminant is a. mixt,nre and atmospheric composition is nss~tmedsimilar to that of origi n d material, i.e. vapor pressure of eaoh component is the same a t the observed temperature. ( a ) Additive Effects, approzimale solu-
tion. 1. A mixture of equal parts ( I ) trichloroethylene (TLV, 100), and (2) methyl chloroform (TI,V, 330).
C,
C2
C,
100
350
T,
- f a = -
CI
=
Solution applic~r ble to "spot" solvent mixture usage, where all or nearly all, solvent evaporates
CX = I/2C,
T, = 700 X 2/9
= 155 ppm
( b ) Gmeml Ezael Solution for Mixtures
(Continued on page A68) Volume 44, Number I, January 1967
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of N Components with additive effects and Different Vapor Pressures.
By the Law of Partial Pressures, (3) Ct = a n , And by Raoult's Law, (4) Pl = Pip,'. Combine (3) and (4) to obtain: (5) C, = aF7pto. Comhining (I), @.I),and (.5), me obtain: FlpP F& Fnpn0 = (6)-+-+ T T T -lF plo + + . . . + F,pm0 -TI T. T" and solvine: for T.
F@
i = n
C
(6.2) T =
F1pP
i = l
.
? = n
C P,p,"T, i =n T =Threshold Limit Value iu ppm. C = Vapor Concentration in ppm. p
Vapor pressure of component in solution. = Vapor pressureof pure component. F = Mol. Faetiou of component in solution. a = Aeonstantof proportionality. Subscripts 1, 2, . . . n relate the above qusntities to components 1,2, . . . n, respectively. Subscript i refem to an arbitrary component from 1 t o n . Absence of snbscript relrtt,es the quant,ity to the mixture. Solnt.ion to be applied when there is a reservoir of the solvent mixture whose composition does not change appreciably by evaporation. =
Exact Arithmetic Solution of Specific Mixture Mol. \It.
Triol~loroetllylene(1) 151.4 Methylehlur~forrn(2) 183.42
Triohloroe~lrylene(1) Methylchloroform (2)
Density 1.46 d m 1 1.3R d m l
T
100 350
M o l fraction in half-andhalf sulution P O st 2S°C by ro1ume 73 mrn HE 0.527 125 rnm Ha 0.472
T = 177 ppm. (Note difference in TLV when acconnt is taken of vapor pressure and mol fraction in comparison with
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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).
IC. T/,V for Mizlures of Mineral Dzrsls. For mixtures of biologically active mineral dusts the general formula for mixtures may be used. With the exreptian of asbestos, pure mineralv are assigned TLV's of 2 4 20, or 50. For a mixture containing 80% bale and 207, quartz, the TLV for 100% of the mixture "C" is given by: T1.V =
1
0.8/20
+ 0.2/2.5
=
8.4 mppcf
Essentially the same result will be obtained if the limit of the more (most) toxic component is used provided the erects are addibive. I n the above example the limit for 207, quartz is 10 mppcf. F a r another mixture of 25% quarts, 25% amorphous silica, and 50% talc: TLTT =
1
--
o.zs/z.s + 0.25/20 + o.5/20
-
7.3 mppcf The limit fur 8 mppcf.
2.5y0qtqnitrtz approximabes
Appendix C Bases for Assigning Limiting Ceiling Values A listed value bearing a "C" designation refers to "ceiling" value that should not be exceeded; all values should fluctuate below the listed value. I n general the bases for assigning or not assigning a C value rest, on whether excursions of concentration above a proposed limit for periods np to 15 min may result in (a) intolerable irritation, (b) chronic, or irrevemible tissue change, or (c) nsroosis of suHicient degree t o increase accident proneness, impair self rescue, or materially reduce work eficiency. I n order for the Committee t o deride whether a. substance is a candidate for a "C" listing, same guidelines must be formulsted on the permissive fluctuation above the limit in t e r n of the seriortsness of (,he response in the categories (a), (b), ( c ) , given above. For this the faot,on given in the table helaw have been used by the Committee. For both technical and
(Cmtinued on page A541 Volume 44, Number 7, Jonuory 7967
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practical reasons, the fact,ors have been pegged to the concentrstion in an inverse manner. I t will be noted that as the magnitude of the TLV increaqes a correspondingly decreased range of fluctuation is permitted; not to decrease the factor for TLV's of increasing magnitude would permit exposures to large sbsolute quantities, an undesirable condition, a condition that is minimized a t low TLV's. Moreover, large factors a t the lower TLV's are consistent with the difficulties in analyzing sod controlling trace quantities.
Permissible Excursions for TimeWeighted Average (TWA) Limits As stated in the preface, the same fa& o n may be med as guides for reasonable excursions above the limit for substances to which the time-weighted average applies. The t,ime-weighted a v e r q e implies that eaoh excursion aboue the limit is compensated by a. comparable excunion below the limit. Thus a value of 6 p p m for H F is permissible for periods not exceeding 1.5 mi", provided an equivalent decrease below thelimit of 3-ppm obtains.
I + to l o
2
l o + to100 1 . 5
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Some Simple Asphyxiants-"Inert" Gases and Vapors Acetylene, argon, ethane, ethylene, helium, hydrogen, methane, neon, nitrogen, and nitrous oxide.
Coming Soon in book form
TLV factor
sine1e suhaequent exposure. "C" listing reoommended o n ohLegorT (L). Manlia"ese-TLV. 5 mg/mJ. conts,ns 11ttie or no safety factor. All value8 ahoald fllietllate helo\\. 5 mc/ma. C listing recommended on esteeorv (L). Methyl styrene-TLV 100 if enoountered at levels of 150 pp!", will prove intensely irnthtin., C listin.
Appendix E
Appendix D Inert or Nuisance Particulates When Toxic Impurities Are Not Present Alundnm (A120s), calcium carbonate, cellulose, portland cement, corundum (AlrOJ), emery, glycerine mist, graphite (synthetic), gypsum, limestone, magnesite, marble, p l a t e r of paris, rowe, silicon carbide,starch,sucmse, tin oxide, titanium dioxide, and vegetable oil mists (excepting castor, cashew nut, or similar irritant oils). A limit of 1765 respirable particles per cc is recommended.
SAFETY in the Chemical Laboratory All the articles in this column from their inception January 1964 through January 1967 will be reprinted in our paperback series. These articles will be grouped by subject matter. Also included will he all the accident case histories. Publication date, a p p r o z i m t e l y February 1, 1067. Probable p r h , 83.00
