Document rpJnKEvV3LBKVJVEJM93eJ3gq

FROM ROBERT P. CARTER HEALTH AND SAFETY DEPARTMENT PITTSBURGH OFFICE 1979 January 11 RE: INDUSTRIAL HYGIENE NEWSLETTER ACGIH TLV List for 1978 The ACGIH Threshold Limit Values for Chemical Substances and for Physical Agents for 1978 are enclosed for your information. The comments made in our Industrial Hygiene Newsletter dated November 18, 1976 regarding the STEL values are still appropriate. These were as follows: "Our initial reaction is to disagree with the use of STEL's as applied in some cases. On page two of the Preface to the Threshold Limit Values for 1976, the definitions for (TLV-TWA), (TLV-STEL), and (TLV-C) are given. The definitions for (TLV-TWA) and (TLV-C) are the same as in the past. The new (TLV-STEL) is defined however as 'The maximal concentration to which workers can be exposed for a period up to 15 minutes continuously--provided that no more than four excursions per day are permitted with at least 60 minutes between exposure periods, and provided that the daily TLV-TWA also is not exceeded.' In instances where the TWA and STEL values coincide, we feel that there is a definite conflict because applying the STEL concept dictates that the maximum TWA cannot be achieved without violating the conditions prescribed by the STEL--in other words, in all instances where the time-weighted average exposure is at the maximum permitted level, there will have been more than 4-fifteen minute periods occurring within 60 minutes of each other where the maximum exposure concentration is reached. "It is our recommendation that the STEL value be ignored until these conflicts are resolved. When it is desired to establish reasonable exposure criteria for short-term excursions above the TLV, and the limit is not a ceiling value, the old method of determining permissible excursions discussed on page 51 of the Threshold Limit Values for 1976 should be consulted." ROBERT P. CARTER lmn Att. UJ ALCOA 511904 0315 Letter sent to Industrial Hygienists and Environmental Health Steering Committee Chairmen & Environmental Managers, Physicians Note: Information relative to health standards proposed or promulgated under authority of the U. S. Occupational Safety and Health Act is sent to overseas locations for informational purposes only. cc: J. L. Brandt, ATC G. H. Farrah, ATC L. W. Ortlip, ATC J. M. Plunkett, ATC W. W. Williams, Fort Meade, Fla. G. R. Hartnett/Albert Lee HC Products Co..Princeville,I11. W. G. Garyotis, Pittsburgh 2 K. P. Karsten/H.G.Sakoian, Pgh.6AB S. I. Roth, Pittsburgh 5AB P. R. Atkins, Pittsburgh 7AB L. B. Sargent, Jr., ATC Duckworth Daley, Kingston W. Brooke, L. W. Nash Co., East Palestine, Ohio C. L. Green, Rockdale Works R. P. Carter, Pittsburgh 7AB B. D. Dinman, Pittsburgh 7AB G. C. Heise, Pittsburgh 7AB V. W. Rieke, Pittsburgh 2AB R. Sharkey, Pittsburgh 7AB J. R. Archibald, Pittsburgh 7AB 511904 03ie PREFACE CHEMICAL CONTAMINANTS .. Tnresnoto limit values refer to airborne concentra tions of substances anc tepresem conditions unoer wnicn it is believed mat nearly an workers may be repea tedly exposed day aner day without adverse etlect Be cause of wide variation m individual susceptibility, how ever a small percentage o> workers may experience discomfort from some substances at concentrations at or beiow the thresno'd limit, a smaller percentage may oe affected more seriously by aggravation of a pre-existmg condition or by development of an occupational ill ness Tests are available (J Occup Med IS 564. 1973. Ann NY Acad Sc: ISl.An 2 966. 1968) that may be used to detect those individuals hypersusceptibte to a variety of industrial cnemicats (respiratory irritants, he motytic chemicals, organic isocyanates, carbon disul fide) Three categories of Threshold limit Values (TLVs) are specified herein, as follows a) Threshold Limit Value-Time Weighted Average (TLV-TWA) -- the time-weighted average concentration for a normal 8-hour workday O' 40-hour workweek, to which nearly all workers may be repeatedly exposed, day after day without adverse effect b) Threshold Limit Value-Short Term Exposure Limit (TLV-STEL) -- the maximal concentration to which workers can be exposed for a period up to 15 mmules continuously without suffering from 1) irritabon, 2) chronic or irreversible tissue change, or 3) narcosis of sufficient degree to increase accident proneness, impair seif-rescue, or materially reduce work efficiency, provid ed that no more than four excursions per day are permu ted with at least 60 mmutes between exposure periods, and provided that the daily TLV-TWA also is not exceed ed The STEL should t>e considered a maximal allowable concentration, or ceiling, not to be exceeded at any time during the IS-mmute excursion period STELs are based' on one or more of the following criteria (t) Adopted TLVs including those with a "C" or ' ceiling" limit (2) TWA-TLV Excursion Factors listed in Appendix 0 (3) Pennsylvania Short-Term Limns tor Exposure to Air- 2 irritation narcosis nuisance or other forms of stress may form the bas<s lor others The amount and nature of the information available for establishing a TlV vanes trom substance to sub stance. consequently me precision of the estimated TLV is also subiect lo variation and ihe laiesiDoct/menra/ron should be consulted m order to assess the extent of me daia available for a given substance The committee holds to me opinion that limns based on physical irritation should be considered no less bind ing man rnose based on physical impairment There is increasing evidence mat physical irritation may initiate, promote or accelerate physical impairment through in teraction with otner chemical or biologic agents In spite of me fact mat serious miury is not believed Mety as a result ot exposure to the threshold Umit con centrations. the best practice t$ to maintain concentra tions of all atmosphenc contaminants as low as is prac tical. These hmits are mended for use m the practice of industrial hygiene and should be interpreted and applied only by a person trained m this discipline They are not intended for use. or tor modification tor use. (1) as a relative index of hazard or toxicity. (2) w the evaluation or control of community air pollution nuisances. (3) m estimating the toxic potential of continuous, uninterrupt ed exposures or other extended work periods. (4) as proof or disproof of an existing disease or physical con dition. or (5) for adoption by countries whose working conditions differ from those the United States of America and where substances and processes differ. Ceding vs ftmt-Weignted Average Unitts. Although the time-weighted average concentration provides the most satisfactory, practical way of monitoring airborne agents for compliance with thehmits, there are certain substances for winch if is nappropriate in the latter group are substances which are predominantly fast actng and whose threshold hmu is more appropriately based on this particular response Substances with this type ol response are best controlled by a ceiling "C" limit that should not be exceeded it is implicit m these definitions mat the manner ol sampling to determine noncompliance with the limits for each group must differ, a single brief sample, that is applicable to a T limn, is not appropriate to the time-weighted limit; here. 4 borne Contamxiants (Penna Dept of Kith.. Chapter 4. An. 432 Rev Jan 25. 1968) (4) OSHA Occupational Safety and Health Standards. 40 FR 23073. May 28. 1975 (S) NlOSH criteria for recommended standards for occupational exposure to specific substances The twaSTEl should not be used as engineering design criterion or considered as an emergency exposure level (EEL) c) Threshold Limit Value-Ceiimg (TLV-C) -- the con centration trial should not be exceeded even mstantaneousiy For some substances, e g . irritant gases, only one category, the TLV-Cetling. may be relevant For other substances either two or three categories may be rele vant depending upon their physiologic action It is im portant to observe that if any one of these three TLVs is exceeded, a potential hazard from that substance s pre sumed to exist. The TLV-TWA should be used as guides m the con trol of health hazards and should not be used as fine lines between safe and dangerous concentrations Tune-weighted averages permit excursions above the limit provided they are compensated by equivalent ex cursions beiow the limit during the workday. In some instances it may be permissible to calculate the average concentration for a workweek rather than for a workday The degree of permissible excursion is related to the magnitude of the threshold limit value of a particular substance as given m Appendix D The relationship be tween threshold limit and permissible excursion i$ a rule ol thumb and m certain cases may not apply The amount by which threshold limits may be exceeded tor short periods without iniury to heaiih depends upon a number of factors such as the nature of (he contamin ant whether very high concentrations -- even tor short periods -- produce acute poisoning, whether the effects are cumulative, the freouency with which high concen trations occur, and the duration of such periods All-fac tors must be taken into consideration in arnvmg at a decision as to whether a hazardous condition exists Ttvesnoid limits are based on the best available infor mation 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 esiaoiisned may differ tiom substance to substance, protection agamst impairment of health may be a guid ing (actor lor some, whereas reasonable freedom from 3 I sufficient number of samples are needed to permit a bme-weighted average concentration throughout a com plete cycle of operations or throughout the work shift Whereas the ceding limit places a definite boundary which concentrations should not be permitted to exceed, the time-weighted average kmii requires an explicit limit to tne excursions that are permissible above the listed values The magnitude of these excursions may be pegged to the magnitude of the threshold limit by an appropriate factor shown m Appendix D It should be noted that the same factors are used by the Committee in determining the magnitude of me value of the STELs. or whether to include or exclude a substance for a "C" listing "ikm" Notation Listed substances followed by the designation 'Skin' refer to the potential contribution to the overall exposure by the cutaneous route deluding mucous membranes and eye. either by airborne, or more particularly, by direct contad with the substance Vehicles can alter skin absorption TNs attention-calling designation is attended to suggest appropriate measures for the prevention ot cutaneous absorption so that the threshold limit is not invalidated Uixtures Special consideration should be given also to the application ol the TLVs m assessing the hearth hazards which may be associated with exposure to mix tures of two or more substances A brief discussion ol basic considerations iwotved m developing threshold limit values tar mixtures, and methods for the* develop ment, amplified by specific examples are given in Ap pendix C Nuisance Particulates In contrast to ftbrogemc dusts which cause scar tissue to be formed in lungs when in haled n excessive amounts, so-called "nuisance' dusts have a king history of little adverse effect on lungs and do not produce significant organic disease or tome effect when exposures are kepi under reasonable control The nuisance dusts have also been called (biologically) men dusts, but the latter term is inappropriate to the extent that mere is no dust which does not evoke some cellular response m the lung when dhaied in sufficient amount However, the king-tissue reaction caused by mhatation of nuisance dusts has the following characteris tics (1) The architecture ot the air spaces remains in tact (2) Collagen (scar tissue) is not formed to a 5 significant extent (3) The bssue reaction is potentially reversible Excessive concentrations of nuisance dusts m the workroom an may seriously reduce vrsibiirty. may cause unpieasani deposits m the eyes ears and nasal pas sages (Portland Cement dust), or cause d|ury to the skm or mucous membranes by chemical or mechanical action per se or by the rigorous skin cleansing proce dures necessary tor their removal A threshold kmn ol 10 mg/m*. or 30 mppef. of total dust < 1% quartz, or. 5 mg/m* respirable dust is rec ommended tor substances m these categories and tor which no specific threshold hmits have been assigned This idtn. tor a normal workday, does not apply to brief exposures at higher concentrations Neither does it apply to ihose substances wh<h may cause physiologic impairment at lower concentrations but for which a threshold limit has not yet been adopted Some nuisance particulates are given in Appendix E Simple Asphyxiants inert' Gases or Vapors A number of gases and vapors, when presem d high con centrations d air. act primarily as simple asphyxiants without other significant physiologic effects A TLV may not be recommended for each simple asphyxiMt be cause the limiting factor is the available oxygen The minimal oxyQen content should be 16 percent by volume under normal atmospheric pressure (equivalent to a par tial pressure. pO* of 135 mm Hg) Atmospheres deficient in (W do not provide adequate warning and most simple asphyxiants are odorless Several simple aspnyxiants present an explosion hazard Account should be taken of this factor d limiting the-concentration of the asphyx iant Specific examples are listed in Appendix f Physical Factors it is recognized that such physical factors is heat, ultraviolet and ionizing radiation, humid ity. abnormal pressure (attitude) and the t*e may place added stiess on the body so that the effects from expo sure at a threshold limit may be altered Most of these stresses act adversely io increase the toxic response of a substance Although most threshold limits have buiR-m safety factors to guard agamst adverse effects to moder ate deviations trom normal environments, the safety fac tors of most substances are not of such a magnitude as to take care of gross deviations. For example, continu ous work at temperatures above 90*f. or overtime ex tending the workweek more than 25%. might be consul- 6 red gross deviations. In such instances judgment must be exercised m the proper ediustments of the Threshold Limit Values Biologic Umt Values (BLVs) Other means exist and may be necessary tor monitoring worker exposure other than reliance on the Threshold Limit Values tor industrial air. namely, the Biologic Limit Values These values rep resent limiting amounts of substances (or Utar effects) to which the worker may be exposed without hazard to health or well-being as determined in his tissues and fluids oi in his exhaled breath. The biologic measure ments on which the BLVs are based can furnish two kinds of information useful in ihe control of worker ex posure (1) measure of the individual worker's over-ail exposure. (2) measure of the worker's individual and characteristic response Measurements of response fur nish a superior estimate of the physiologic sutus of the worker, and may be made of (a) changes in amount of some critical biochemical constituent, (b) changes it ac tivity ot a crdcal enzyme. (c) changes m some physiolo gic function Measurement of exposure may be made by (1) determining tn Mood, urxte. hair, nails, n body tis sues and fluids, the amount of substance to which the worker was exposed. (2) determination ot the amount of the metabolite(s) of the substance in tissues and fluids. (3) determination ot ihe amount ol the substance m the exhaled breath The biologic limits may be used as an adiunct to the TLVs for air. or m place of them The BLVs. and their.associated procedures tor determining compliance with them, should thus be regarded as an effective means of providing health surveillance of the worker Unlisted Substances Many substances present or handled m industrial processes do not appear on the TLV list In a number of instances the material is rarety present as a particulate, vapor or other atroorne con taminant. and a TLV is not necessary In other cases sufficient information to warrant development of a TlV, even on a tentative basis, is not available to the Commit tee Other substances, ol tow toxicity, could be mduded xi Appendix E pertaining to nuisance particulates This kst (as welt as Appendix F) is not meant to be ait inclu sive. the substances serve only as examples. In addition mere are some substances of not incon siderable toxicity, which have been omitted primarily be cause only a kmited number of workers le g . employ- 7 511904 0317 s o1 a single punt) are known to ftra potential exposure 10 possibly harmful concentrations "Notice of intent ' At the beginning of each year, proposed actions of me Committee tor the forthcoming year are issued m the form of a "Notice of Intended Changes " This Notice provides not only an opportunity tor comment but solicits suggestions of substances to be added to me list The suggestions should be accompanted by substantiating evidence The list of Intended Changes follows the Aoooted Values in me TlV booklet Values listed m parenthesis m the "Adopted' list are to be used during me period m which a proposed change for mat Value is listed m the Notice of intended Changes ligM Sutus 6y publication m the Federal Register (Vol 36. No 106. May 29. 1971J the Threshold Limit Values tor 1966 were made official federal standards (or industrial an Since 1971. new standards tor certain of these substances have been promulgated by OSHA. Repnnt Permission This publication may be reprint ed provided that written permission is obtained from the Secretary-Treasuier of the Conference and that it be published m its entirety 8 SaMtance ANTU <-feapnthyl trviouroa) Argon . . * Arsenc S compounds US As) ** Arsenc tnoime producten (as As) Arsine Asbestos (all forms) Aspnatt (petroleum) fumes . . * Atrume . ... Azmpnos-methyl -- Skm Barium (Soluble compounds), as 6a Baygon (propoiur) Benzene ................. Benzidine producten -- Skm . p-Beruooumone. see Qumcne.................. Benzoyl peroiide ...... Benz(a)pyrene............. Benzyl cMorde.............. Beiylfeum..................... Bwhenyt.................. C Bepnenoi A. see Oigtycidat ether <DG) Brsmum letignde......... Bsmuth tttiundc. Se-doped............... Borates, tetn. sodium - sens. Anhydrous........... Oecanydraie............. Ptnaffedute.. . . Boron oux............ Boron tnOromtie . . . C Boron tnflvonde......... Bromine. . .. Bromne pemahuonde... MOTTO TEVTATfVt VALUES_______ VALUES TVtA STEL PP" /*" 03 09 f --F F _ (0 5) __ _ _ (Ala) __ _ 0 05 02 -- -- -- (All) -- (AH) _5 to __ 10 __ _ -- 0.2 -- 0.6 __ -- 10.A2 0s 05 30. A2 _ -- __ _ 2 __ _ _Aib Alb 01 04 --$ -- A2 15 -- 0.002 03 2 ---- -- A2 ---- -- 0.Q25 02 1.5 06 4 _05 30 -- 10 -- _ 20 $_ 10 1 -- s-- -- --1 -- _ 10 20 1 10 3 30 1 3 __ -- 0 1 07 0.3 2 0.1 07 0.3 2 CfeWUi wears refer 10 Append** fogtnoiet l* twu 0) M Piqv 31 *'$r ftotcc W Caarv* *i9?lAoaiA 10 AOOfTEO VALUES TVtA Tebelfefeff m%m*` TENTATIVE VALUES STEL tern- mfm'4' Capufoi (Orroiatan*) -- Skm Captan. Carbaryi (Sewn*) Camofurin (Furadifl*) Carbonbtacfc Carbon woule " Carbon disulhde -- Skit Carbon monorte Camon totraoromtie Carbon tetuchtorde -- Skn * Carbonyl cftfoule (Phosgene) . * Caibonyt ftuorde . Catechol (fyocatectoi) CetaAOM (paper fiber) . Cesium hydroxde .. . CMotdane -- Skm . .. CTHonnated camphene -- Skm... CMomawd ftphenyf aulc..................... Chtorne ..................... Chtorme depute.......... C CMonne trdmonde ... CCMoroacetaiOehyde........ a CMoroacctophenone (PtMnacyt chlorite) . . Chlorobenzene (MonocMorooenzene). o-Chiorobenzybdene matonoente -- Skm .. Otorobromomcthaner BromocruorometAane 2-CMoro-t. 3-butadwne. see fi CMoropnne -- Skm .... Chtorodihuoromethane CMoroikphenyl (47% CMorme) -- Skm _ -- _ -- -- 5.000 (20) 50 01 to 0t 5 S -- -- -- -- _ 1 01 0.1 1 0 05 75 005 200 25 1.000 -- 01 s 5 01 3S 9.000 _ _ -- _ 15 000 160) (30) ss 400 1 4 03 65 20 04 __ 15 _ 20 __ _ 2_ 05 -- 05 -- 05 _ 33 03 03 04 3-- 0.3 -- 350 -- 0.4 -- 1.060 250 _ ts 10 7 18 000 (90) 440 4 130 _ _ _ 20 2 t 2 9 09 -- - -- -- 1.300 90 35 3.500 1.250 1-- 125 4.375 2 Qpitw loners retv to Appanwces **S Mouse or Mended Otawes MB78 Addiitcn 12 AVOAOLPUTEESO TEVNATLAUTEISVE TWA STEL fabeteacs ppr m%m*' ppar |/e^" *****C***AAAA422AnAAAAAAAAAAAAAAsAAAAAAA----eccccJbJccmmmcncnniiiiccnAnAcAAyyyyeedeuEceecea((uhSp1prewtseirtiAAmmmmrmmtremoyriiiin-ttttetmaiyt-ytebmsyeaoyniAoonGhcncvmcdusagpnnilmmf7oowijmolyneooednoemdmmaufooiCmdryo$-nlcunen--mnKamnioanuoneomDonnmltabIryoeia--ewoiaefnephdpecumydnyyoaieltd)hdc--nceyhytrymmte(igtu<dtSam-pohetlAhtt6edyrdlreyet0rrSmcrhilasukui!efafiia--cdf-ntnoesoetSkei)nrt--Cmn--snnruarmreutQaxmnkuoaiouudelo--tmiibhemfysetdei$oeiseamf)erlSu.Sekctcumonsrsp--mkdk.SSjemyeemoame.kebi.ufemx().eSannsksedke. eisn _ 1.0to401o00f05 1220----002t11) --52 -- 02535 -- 1to(--25o5) 01 -- -- -- 2.41--07282to00005 _ 1.21S--5--51O005 00(704291253455305) 205--.30S (3--042) A21lb22 1--30 -- 1828 3652 10 -- (6517319000) 115--5--00 05 -- (0 5) -- 05 -- 10 S. A2) -- 3.02>0O--72--30007S 10.(0008017158660850) A412ib480 12457 20 88020--000 -- -- -- -- Cfwl9aSet7netipfA*ieopMt*ieattosnrmwou*egw>iae%nSmexP*mipQevvc3mnipti 9 AVOAOLUfTEESO TEVNATLAUTEISVE TWA STEL lebefen PA*" *" CCCC***ttM2BBBB2hanCBBnnCCCCpBlBCCCCCeee------u-uurruuuaaauuanaacanaBaBBBtdBBoomCt3C(CVtec(pO-mtitlpmtc-llddl--aadycau-ccyaBuucumymuBuBhB-nrBerrrBmmnuadmiiiislitelbontQiptuottuaauutu-aoutGyuuyodyoeuyisoaumBipehdwlemriimmmmimCotnrsautiutfttlifcutrctco.hunyyubyoo6)ysooye)tcayagmdnmimmaaraearlfctl.rcloaletbncto--r)crl.l)iyyymeacoycotdypa,caaa..ri.eaeterctiio.v(oclsmohisaeooa.otrutdlla,ttr1ch...coecccoue.--atyaphnbannmtr--.Snu.er.tfs..i.ejooenmeotnJut.oonaoeynte.eseato...--(ahh.okeietmnloma.tu.eatc.u).n.hmt.oo..S.SA..ami--eti.sC.d.m6fue.oh.eBll.k..(tu.keC.......See.BthtaC.m(....me.um....tc.e..au.../h.ke..n.Su.d..t......s...my..ae.rl(e.t.)....t.ka.y.....l..n...A..f.s......slm.(.........e...a...s.........)s.... 20050 1.B0O0O0 20050 T21I1SO0550s1OO0000o05 -- 0510505 _ _ -- _ __ -- -- --2 __ 5 1.0505 2--50 21..240300 1.275500 51905 _ 300 492793IS55415051O00005005 222I1S5--------505O0000 0.1 -- 212675005 -- ---- 20 005 _ 005 _ (A2) __ 0155221 __ -- _ _ 3 201 __ 10 1.30--0 21..775600 B_BS 11..17941--9----265--900000 -- 1------20 0.2 _ __ _201 __ __ 10 403 C**a1*Sp9ee7ae1lNwAoMtvesieeenrelfkeurmtoeaedppOwwtnaote*s 11 AOOfTEO VALUES TENTATIVE VALUES Substance TWA sm ppm" mg/m**' PPf m/m**` ChCiohrioodrmipnee) n--yi (S5k4m% -- 05 -- 1 **C***b12CCoo0CC12CCCCCCa-------MhhnhCCCConChhOC3Se((Cc(6-(pmtCcptiIs(rEha7ErCo/roOoh-ohhMhhckS-poMyMvooahooetyht(rrnsirmrpilhimriNeheooboompouimfomotdrpoooorooareycareoyrosyerrrorcrrrotoparorkrlceonooMeioorolosoirmtmooumMetxntciry(Phmrse.ti-rbbpscepoh-afonymoa(orcemyatoiea2aoiiresaemCyos-h-mewkreyaidectsp.her,r,.adr(ecn)raMrctbniotcoCNe.inefAcyehrmcScsn*fo.ooem)nmyea.Oute),dhnr.o-op.ap.rfnvepeSSrrtrt).rml--tea(nr--eo(aatos.yomm-aoa.Ve.en..d--fsp--)tttmm.ssecmheemeria.r.r..CetSvofySotaCen..--)ryse.rSptukStckMwe.l.sc*.asmsmkkim.f.).nm.m....ge...... 5 20 13 (Ale) 100.(002A0261201i 50.<At09oA0lao?17 S5O0 22065.250 10 0 05. All 005 _ 0.05. Ala -- 0150 C 2. Ala 10 (A1C) __ (03_53_) 7755 __ _ -- 40 All (13--52) 34073650 20 Ala _ -- __ Ata " Cotbuamltem(eastaCl,od)ust and -- (OM - - Cjpui <evs itfei to Append** Footnoin u inru e> *m hip* 3i 'Swfeoiceoi nvM Cheng* * 1978 toonm 13 511904 0318 Sutelence *' OO2CCCCCCCCCC0OOODOCCCCCC12C0O10-Dyuy.royiyeorryyoyeiy'ywmaohuota2oDatSad|EaTo2(--mcpc4--coco2csmVnarr4a-Efpo-rrncnuaoaiooe-piueoiioo--OoooopmoPueohhooO*roetOmie0too(smmimnrdmhnneafinynnoymyDnigSSotnnottte'tDeeiyaohidmneecsaOteanbenmwoeaa(arcec1n*a,lepdiinuty2auxmiaeenerdmmtar'amft--inKtom&soh--e*ryneStatraOnonenhmnnpymemtsea*oidoeetheo4ea--oaM|ido--O*iedlaAcsiortyCc-onymSnei--hnuSdo)Omerpdceaob-eeeanahamidaen4e*nthShtSitm)emwnrhmsipcO-.-.iiiomrpa--Skeoatmafooel.mhsmla)u--frfee.m)el.tevem.o.en..sSfton.U.f.houaS...syCs.yx.m.nlae.ly-u.)---ome-)..t.. *f*to&loSmeoeh*peost3e13at omrrmu tge)ntooMt PCahga*ng3eis Amooumllo TWA PP" %<**' __ ---- " 00212E01* 25 --SO 33--0--S?s0t1oOo00s0 11..002222. 412240500SS20S200006S0 10 "` 1 00000s11 00.311 so 240 00--1201 0002..411$ (2--0) (1S53) 21 1S4 14 TEVNATLAUTEISVE STU __ _ -- -- -- 02206E --6 3IS--7------------7--OS$ 1.334--60----------2----0150080 -- 20 3 000.0I.S33 00.393 7S 360 ------ 0--.3 -- (M--| (23061 42 2160 tetelMce AOOfTEO VALUES TWA ppaT g//' TENTATIVE VALUES 6TEL ppw g/m*4' C DqfrcWyt ether (DGE) 05 Otiydroxytefuene. see Hydroqumone . -- Owsobutyt ketone . Oopropyiamme -- Skm. . .. 25 5 Oenetnoxymethane. see MeThyiM 0methyl acetamide -- Sam .. . * Oeneihyl aitemyl 1.000 10 chloride .................. A2 Omethyrame* .......... 10 Oenethyiammoberuene. see XyMene -- Skm Omtethyianilne (N. 5 H-OenethylanAne) -- Skm .................. Omwihytberuene, * 5 Xylene -- Skm . .. OrmethyM. IX 2-dibromo-2-dichlofoelhyr phosphate, see Orbrom. ... (hmethyVormamde -- -- Skm...................... 10 2, 6-OenethyW-heptenone. Me Oasobutyt ketone . 2$ 1.1-Oenethyttwd rune -- Skm .................. OenethylphthMU . . .. 05 -- C Ounethyi sUfate -- Skm. 0.1.A2 Dmtroberuene (all ftomeri) --Skm . . . 015 Dmaro-d-crtsot -- Skm. 3. $-On*ro-o-toa*armde (Zoaiene*)................ Dmerotoiuene -- Skm .. Dionne. lech grade -- Skm ..................... Omuihton (Delniv*) -- -- _ -- SO Skm .. ............. 3 2 ISO 20 3,100 35 A2 11 25 25 435 3 30 ISO 1 5 0.5. tt 1 0.2 5 1.5 IX 02 -- -- -- 1.250 15 _ -- 10 10 IX -- 20 -- _1 -- 05 -- -- -- -- 4 ~ -- 3.67$ SO _ -- x so 650 6 X -- 2 10 " 3 0.6 10 5 -- Caona letters 'Her te appcnttcee foomora la thru g) Me Pape It *1971 MMen 16 Tililaan Ethyl sec-amyl ketone (4-Methyl 3- heptanone) Ethyl teneene Ethyl (Homme EthyNtufyl ketone (3-Heoianonei Ethyl chiorme Ethyl 0t*' Ethyl formate Ethyl mercaptan *' Etnyi snecatr Ethylene C Ethylene chiorohydrm -- Skm Ethyienediamete ** Ethylene dtpromoe see 1 2-OOromoefhane ** Ethylene dtcMorde. see 1 2-OKMoroethane Ethylene grycoi PirtcuUte Vapor C Ethylene gtyed WMratc and/or Nerogiycerm -Sam Ethyleneglycol monomethyl ether acetate (Methyl cenosotve acetate) -- Sam Ethylene omde Ethyienenme -- Sam . Ethykdene emonde. see 1.1-DcMoroernane C EthyMene norbomcne N-Etnytmorphoanc -- Skm Fensuhothon (Daune) Ferbam Ferimranadium dust Fiuorme las F) Fluormc Cap<* ne>v >et< te Appnet **Se Hoik* e* mwece Cnanges AOOfTEO VALUES TWA PPor mg/m**' TENTATIVE VALUES STEl fpr g'*1*' 25 IX 2X X 1 OX 400 IX 05 dXl f 1 10 (20) (50) IX IX 435 125 6 2X 230 2.6X 1 200 3X l (6X_1 75 1 250 500 IX _2 f 3 25 _ (155) (Ml I2X) (75) 10 250 125 545 1 no 345 3 250 1 500 450 __3 _ (230) (3X) 20 325 or 2 25 120 35 170 _X X 75 135 05 1 _ _ _200 610 250 1.010 5 2S _20 --_ _ 94 01 10 __ 1 25 _ _ 20 03 1 22 4 16 Intelmc# 0utyi pntnaiate . .. C Ochioraceiyene C o-Ociuoroteruene - p-DeMorobentene OcNoroteiuome -- Sam . . . Dcft&oditivoramtfiune 1 3-DcmoroS S-dimethyi hydamom 1 1 -OrcNoroethane * 1 2-0<moroethane 1 2-Dcttoroemyiene . . Ocworoethyi erner -- Sam ** Ocmorometnane. see Methylene duorrte ** Ocmoromonoltuoro- methane Cl i-Denioro-1- neroetnane 1 ?-DcMoropropane. see Propylene dchiorme Dcniorotetratiuoroetiune Dcftiorvos 1DDVP1 -- $am Ocrotophos (BrOrar*) -- Sam Ocyciopentad*ene Ocydooentadtcnyi iron Owtdim -- Sam. Oretnytamme 0*tftyiam<noeiftano< -- Sam Dmyen< tnamme -- Sam 0thyi amei seeEihyi finer Ociftyi phtnaiate OdiuoiodiOromomeirvme ADOPTS) VALUE! TWA ppw*` _ 01 SO 75 _ 1.000 !/*' 5 04 300 450 A2 4.950 -- 02 200 610 (SOI (2X) 200 790 s 30 1200) (700) 11.000) (4.200) 10 60 75 1 000 01 -- s -- -- 25 10 1 400 -- 100 350 7.000 1 0 25 30 10 0 2S 75 50 4 1 200 5 660 TENTATIVE VALUE! 6TIL _ -- -- 110 -- 1250 -- 250 (75) 250 10 (250) -- 10 -- -- 675 A2 6.200 04 1.010 (300) 1000 60 (170) -- '` 110 1.250 03 -- -- -- -- " -- -- 500 -- 150 510 1.750 3 -- -- 20 0 75 -- -- -- 1.500 10 1.290 Caem win 'w io >wxtn * * Sm Iookc or mom Charon IS letataece Diphenyl, see Biphenyl . Oiphenyiamme C Diphenytmeihane dusocyanate. see Methylene bsphenyi isocyanate (M0<) . . Dtpropytonf giycot methyl ether -- Skm .. Diquat......... Oi-mc, octyl phtnatne (Di-2-ethylheiylpnthatate) ......... Daulhram............. Dsyston -- Skm... 2. 6-Oflert. butyt-p-crewl......... Owron................... Oylonaa...................... Emery ..................... Endosahan (Tiwodan*) -- Skm................ Endrm -- Skm . ** Epchtorhydrm -- Skm EPN --Sam .. . 1. 2*Cpoxypropane. Me Propylene onde . .. 2.3-Epoiy-i-propanoi. steGiycWol...... Ethane . . Ethanethmi. Me Etnyl mercaptan . . Ethanolamme. Ethion (NtaiaU*) -- Skm 2-Ethoeyethanol -- Skm 2-Ethoiyetnyt acetate (CeKosohe acetate) -- Skm . . Ethyl acetate Ethyl acryiate --Skm Ethyl alcohol (Ethanol) Ethyiamese .. . AOOfTEO VALUES TWA ppm*' m%m*' 02 t 5 -- 10 TENTATIVE VALUES 6TCL ppm*' agi 06 4 -- 20 0.02 02 IX 600 IX 900 -- 05 -- 1 5 to _ 2-- 5 -- 0 1 -- 03 __ 10 20 __ 10 -- -- -- 0.1 -- -- -- i-- 20 __ 0 1 0.3 -- 0 1 -- 0.3 (5) (20) (10) (40) -- 05 -- 2 tx 240 IX 360 SO IX 75 225 F --f -- 05 1 2 3 3 66 -- 04 -- IS -- IX 370 IX 560 IX 4X 25 1.0X to 540 1,400 IX 1.9X 16 IX -- -- -- -- 610 -- -- -- -- Clp4 W1VI rate W HWttcfl * * Sm Note* MUM OianQ* 17 Iterate* FiuorotrcWoromethane . C formaldehyde .. Formamme Forme acM .. . Furlural -- Skm............ Furluryt alcohol -- Skm . Gasokne Germenwm wtrahydrde Glass. Abrowf' or dust. C GkrOrHdehyde. aderated or vnactnrated.. Gtycerm met.............. Gtyctftf (2. 3-Epoey* 1-propanol).. Giycot monoethyt ether. -- 2-Ethoeyethanol -- Sam................. Graphu (Synthetc) GutfMon*, Me Aamphoe-metnyl -- Skm ...................... Gypsum . . .. Hatmum . . Hekum ......... HepucMor -- Skm Heptane (n-Heptane) HeiacMorocyciopena* dene . heuchioroethane -- Skm . HeucMorontphtnaiene -- Skm Heuttuoroecetona. Heune (n-heune) . . * Huamethyt phospnoramwe -- Skm 2-Heaanone. sm Methyl butyl kolone -- San Huone (Methyl sobutyt ketone) --Skm AOOfTEO VALUES TWA **" mtm*' TENTATIVE VALUES 6TEL ppm*1 m%m* t.OX 2 20 5 5 5 -- 02 __ _ -- S.6X 3 30 9 20 62 06 to 1,250 _ X _ 15 10 __ 0_6 (0-25) E __ 7.QX __ 45 _ X 40 62 16 __ E X IX 75 225 IX _ 370 IX 1 560 02 06 __ I __ 20 _ 05 _ 15 F F-- _ 0.5 __ 2 400 1.6X $00 2.0X 0 01 0 1 OX 03 1 10 3 X 02 _ 06 0 1 0 7 01 IX 360 125 4X A2 A2 _ 25 IX 40 165 IX 410 125 510 C944' tetters IHer to 4ppmdC ooinoi I* thru 01 tet 31 *i97 otn ''$ Korea of HWNod Owe* 19 511904 0319 UMUKI AOOPTIO VALUES TWA ppar mg/m**` sec-Moiyi acetate hoayttno glycol Mydrum* -- SAM Hydrogen Hydrogenated terphenyb Hydrogen bromde Hydrogen chloride Hyfirogon cyande -- $fcm Hydrogen tiuorde Hydrogen peroude . Hydrogen seunde Hydrogen sulfide. . . Hydroggmone ....... inoene .. Indium A Compounds ( m} iodine . .. . lodolorm ........... lion oid tumo Iron pentacarbonyl....... Iron salts. sofeiM (is Fe)........................ Isoamyi solits.......... Isoomyl OKOhOl . .. tsotwtyl ocdtito........... tsobutyi erconoi . . tsophorone............ Isophorone ftBOcyanste -- Skm. isopropyl aceate........... Isopropyl Jcoftoi -- Skm tsopropytamma .... isopropyl etna r............ ksopropyl glycdyl ether <GE) .................. Kaokn........................ Kstena .................. Uod. vorg . tunes A dusts las . UM arsenaii (as Pb) ... Lmd chremse (as Cr)... 50 25 0 1 A2 05 3 S (10) 3 1 005 10 -- 10 _ 01 06 03 0.01 _ 100 100 ISO $0 s 0.01 250 400 s 250 50 _ 0$ . -- -- 300 125 01. A2 -- 5 10 7 (11) 2 1.5 0.2 15 2 45 0.1 1 10 5 0 06 1 525 360 700 150 25 ooe 950 960 12 1.060 240 E 0.9 0 15 0 15 0.05. 42 TSfTATM VALUE! mi pm* mi*1" __ ---- ---- F-- ---- ---- ---- (15) (16) ---- 23 ---- 15 27 --4 15 70 _ 03 ---- 1 20 __ 10 ---- __ 2 125 655 125 450 167 675 75 225 ---- __ _ 310 1,165 500 1.225 10 24 310 1.320 75 360 __ 20 1.5 3 _ 0.45 -- 0.45 ---- Capflai wntn (0m to <<p-- **Se* horn 0 nunem Otonoii 20 Iillire AOOPTEO VALUES TWA ppw 6'*' Methytacryionitrac -- Skm Methyiai i lOimemoxymetrune) 1.000 Memyi alcohol (methanol) -- Stun 200 Methytamme 10 Methyl amyl alcohol see Methyl soOutyi carbnoi -- Skm 2S Methyl 2<yanoKrytaie 2 Methyl ivamyl ketone (2-Heptanone) 100 Methyl bronude -- Skm 15 Methyl Putyi ketone, see 2-Heunone --$km Methyl cehosohre -- Skm 25 see 2'Methoiyetnanol 25 Memyi cenosorve acetate -- Skm. sae Ethylene gtycoi monomethyl ether acetate......... 25 Methyl ehiordc 100 Methyl cMorotomi (1.1. MrcMorocthane) . 350 Methyieydoneune MethytcyOoteianoi 400 SO 0*Mthyycloheaaflone -- Skm ... Methytqrdopentadmnyi 50 manganese trcarbonyl (asMn) --Skm .... 01 Methyl demelon -- Skm -- C Methylene brsphenyi socyanate (MDI) .. 002 " Methylene chtorde (dichioromftnane) 4. 4-Methyiene be (2<htoraiwkne) -- (200) Skm 0 02. A2 C Methylene bs (4-cydo- heiykaocyanate) 0 01 3 3.100 260 12 100 8 465 60 100 80 120 210 1.900 1.600 235 230 0.2 05 02 (700) 0 tl TENTATIVE VALUES 6TEL ppr- mg/m* 2 1.250 250 -- 6 3.67$ 310 -- 40 160 4 16 150 710 ---- 40 165 35 120 35 170 125 260 450 2.360 500 2.000 75 350 75 345 0.3 0.6 -- 15 __ (250) (670) A2 -- Cao*i toners <*if to Aeootoices "See Dote* o' kitonSed Cn*ngn 22 UMWI ADOPTED VALUE! TWA ppm" mg/m**` TENTATIVE VALUES STEL ppm" mg/m**' Ntrcoxde . - 25 p-hkroamkne -- Skm 1 Ndrooenane -- Skm 1 p-NerocMoroberttene -- Skm _ 4-herodipftenyl . -- Ndroerhane 100 C Nfrogen dioide 5 Marogen trifluonde to C Nkrogiycerm -- Skm or Nrtromethane 100 t-Nnropropane . .. 25 *' ?-Nropropane . (25) N-Nkrosodiinethytamne (dimethy Mrosoamme} -- Skm . . _ Neratokitne -- Skm . 5 Ntrotrchioromethane. see Chtaropcrm 01 Nonane ..................... 200 OdacMoronapnthalene -- Skm .......... -- Octane.......................... Ot mat. mineral... . --300 Osfflum tatroxdc (u 0s)...................... 0 0002 Ouecaod.................... __ Oeygen dHtoorale........ 005 Oione...................... Parafkn u tune . . 0--1 * Paraquat, respirable sues....................... -- Paratfkon -- Skm . .. Paniculate polycycfcc srornate hydrocarbons (PPAM). as berutne solubles -- Pentaborane . 0005 Pentechiofonaonthetone PmacMorophanol -- -- Skm ... 30 35 62 52 1_ AID _ 310 150 9-- 29 15 2-- 250 ISO 90 35 (90) A2 _ X 10 07 1.050 01 1.450 y 03 250 -- 375 0.002 1 01 02 2 0 0006 __ 0 15 0.3 ~ 0t -- 01 0.2. AU -- 0 01 0.015 05 05 45 12 IQ 2 Alb 465 -- 45 -- 375 135 A2 60 2 1.300 03 1.600 10 0006 2 03 06 6 -- 0.3 Ala 0 03 2 15 Capaai tottai rttm to Appm*ces Foouwtts (a thru g) sat Pag< 3' * 1978 Addrton "Sac tooina el Mmded Ovanqe 24 kHwi imesion Imdane -- Sam Lithium hydride l P G (LOurlwd ptuoteum gas) MaQnesae Magnesium otiQe fume las Mg) Mautfnon -- Skm Maie< anbydnoe ; Manganese 4 Compounds (as Mn| . Manganesa cyciopenuatnyl trcarbooyl (as Mn) -- Stun * Mangviese Tetrouda . Marbie/cncmm carbonate Mercury (Alkyl compounds) -- Skm (as Hg) Mercury (Ail torms ocepi alkyl), as Hg Mesityl oide Methane Memanetrwx seeMetftyi mercaptan Metnomyl oannax*) -- Sat . . MefftoiytMor 2-Metnoiyethanoi -- Skm (Methyl ceiiosoive) Methyl acetate Methyl acetylene (propync) Methyl Kefyfcne-propad'me mature (MAPP) Memyi Ktyttie -- Skm . ADOPTED VALUES TWA ppte*' _ -- ~ mgm*' E 05 0 025 1.000 " -- __ 0 25 1.600 E 10 10 1 5 -- 01 "1 E 0 001 -- 25 f 05 -- 0 01 0 05 100 1 25 10 25 200 1.000 60 610 1.650 1 000 10 1.600 35 TBTTATtVC VALUES tTU ppm" mg/m**1 _ 20 _ 15 "-- 1,250 -- __ _ -- 2.250 20 -- -- -- __ -- " 0 003 __ _ F -- _ ` 35 250 1.250 03 -- 20 003 0.15 _ -- -- _ 120 760 2.040 1.250 -- 2.250 -- CapA* nn*i (0m * 1071 ton 21 Ubetaace Methyl ethyl ketone (MEK|. see 2-8utanone. C Methyl ethyl katana peroade. Methyl tormate .. Methyl made -- Sam Methyl Boamyl ketone Methyl Booutyl cerbmol -- Sam ... Methyl Booutyl keiont. see Heone -- Skm . Methyl Bocyarwe -- Skm......................... Methyl meraptan .. .. Methyl nwthaoylBt .... Methyl parathmn -- &m Methyl propyl ketone. see2-Penunone....... C Methyl stocaU............ C-M#thyl styrene Moiybdmum (es Mo) Soluble compounds . insoluble compounds Monocrolophos (Ajodrm*) Monomethyl andme-- Skm C Monomethyl hydratme -- Skm Morpnoene -- Skm Napnthaiene . OdtapnihyUmme Neon Nani caitonyt Mcfcti metal Ncaei. soiuoie compounds (as Ni) NKkei sufhde roastmg. turns A dust (as fci|. Ncoime --Skm Mere k<9 Aoomo VALUES TWA ppm" mgim** TENTATIVE VALUES KIEL ppm" mg/m*" 200 02 too 5 too 25 too 0 02 05 100 -- 200 5 100 __ -- _ 2 02 20 10 -- F 005 -- __ _ -- 2 590 t5 2S0 26 475 too 410 0.05 1 410 0.2 700 30 460 5 10 0 25 9 0 35 70 50 Aib -- 035 1 01 1. All 05 5 300 _ ISO to 150 40 125 __ -- 125 -- 250 -- -- _ -- _ 4 __ 30 15 -- F -- -- __ _ -- 4 665 _ 37S 56 710 165 510 _ -- 510 0.6 675 -- -- 10 20 _ 16 __ 106 75 Alb -- -- -- 03 __ 15 10 Caeeai ns retef to Apeenotei toomaet i fuw si sm km* 3< 23 feletMti Penueiythriol.. Pentane................. 2-Peanone .......... Perchtoroethyiene -- Skm ..................... Perchioromethyt mercaptan.............. Perchioryl ftuonde . Phanol --Skm .......... Phenothaone -- Skm . p-Phenytone damme -- Skm...................... Phenyl ether (vapor) .. . Phenyl ether<Oiphanyl nurture (vapor) . .. . PhenyMthyiene. see Styrene, monomer..... Phenyl giyddyt etn*r (PGC)....................... ` Phenyl mercaptan.......... Phenythydozvu -- IkM :Phenyipnosphme.... Phorate (Thmut*) -<> Skm . ... Phosdrm (Mtvwphot*) -- Skm..................... * Phosgene (carbonyl ciuorde) .. Phosphme PhosphorcKd PhaspnonB (yedov| ., * Phosphorus pentscniorde.......... Phosphorus penusuihde Phosphorus tnosorde . Phthekc anhydnds . .. m-PhthdodMMtrei .. . Pidoram (Tordon*) Pertc acd -- Skm . . Perc^ (2-Pwalyi-l. 3mdandKMU) nastar ol Pans . ADOPTEO VALUES TWA ppm*' mg/m^' _E 600 1.600 2tt 700 100 670 01 06 3 14 5 19 --5 _ 0.1 17 17 100 420 10 60 0.5 2 5 22 005 025 - 005 0 01 0.1 0 1 04 03 0.4 --1 -- 01 -- (1) --1 05 3 16 --5 -- 10 01 01 1i TBfTATIVE VALUES tTU ppm" g/m**' _ 20 750 2.250 250 875 150 1.000 __ -- 6 26 10 36 -- 10 __ -- 2 14 2 14 125 525 1$ 90 ---- 10 44 ---- - 02 0.03 03 ---- 1 --3 -- (3) -- -- -- 03 03 - 20 Upon toners refer to Aepenfecn *1070 *atn ** $w HotxM el eittnem Otongei 25 511904 0320 lUtllMI ADOPTED VALUE! TWA #**' imf TSTTATM VALUES ITU pper */**' Platinum (Soluble salts) as Pi PoiycftKHoooMorts see Cnio'OdipnenyH -- Skin Powtrafiuofoettytene decompositmn products C Pousswm nyorwbe Propane D-Piopmtacione .. . . Propargyt alcohol -- Skm .............. n-Propy* acetate . Propyl alcohol -- Sun n-Propyt narate Propylene Propylene frefuorden. 2-OctNpropropane). C Propylene gfyooi emxme -- Sam . Propylene plycol monometnyt ether. ... Propylene vneie -- Skm. Propylene side . Propyne. see Methyl acetylene .............. Pyrethrum ............ Pyndtne...................... Ounone................. ROK -- Sam............... Resorcmt.................. Rhoduim. Metal fine and dusts (as Rh) . Sot** salts (as Rh). Ronnal Rosm core soroer pyroaystt produce (as lormaidthydi) Rotenone (commercW) Rouge .. -- F -- 1 200 200 25 f 75 02 100 2 100 1.000 -- s 01 -- 10 __ -- -- 0 002 61 2-- --f A2 -- 23 640 250 500 250 105 40 --F 350 110 2_ 360 150 S-- 240 ISO 1.650 5 1$ 04 1.5 45 01 0.001 to 1.250 -- 10 0.3 -- 20 _ -- -- 01 5-- E 61 -- -- A2 6 1.050 625 470 -- 510 _ 540 -- 360 2.040 to 30 2 3 90 03 0 003 -- 03 10 20 GlpUi tctlcr* i*Ur ID Appantte* *1971 AOPIMA 26 IdMaatr TE0P --Sam Teflon* decomposnon products TaUurum i compounds (as Te) TeNurum heuftuonde, as Te.............. TEPP-Sam. . **C Terphenyh 1.1.1. 2-Tetracntoro-2. 2-afluoroethane 1.1.2. 2-Tetrachioro-l. 2-drftuorotfftam. .. 1.1.2. 2-TetocMorocthane -- Skm . TetmcMoroeOiyitne. see PertNoroetriyiene -- Sfcm........................ TetfAtorometham. see Caibon tetocMondc -- Skm .. Tetrachloronapnthaiene .. Tetraathyl Mad (as Pb) -- Skin.................. Tetrahydroh/ran ........ Tetnmvthyt Med (as Pb) - Skm................... Tetramethyt succmon ante --Skm Tetiandrwnethane........ Tetryl(2.4. 6-tnNtropftenyt- methymrtnmms) -- Skm........................ ThaMum. soluble compounds (as Tl| -- Skm ....................... 4.4 -TrNobe (6-tart. butyHh-cmaoi)......... Tluogiycokc aod.......... ADOPTED VALUE! TWA ppr' m%m*' - 02 -- 61 ~~ 0 1 002 0 004 (1) 02 005 (9) 500 4.170 500 4.170 5 35 100 670 10 6$ --2 -- o.ior 200 $60 " 0.150" 0.5 3 t6 15 0.1 -- 10 15 TENTATIVE VALUES 6TEL ww' Mi/w*** - 06 -- 61 --~ --_ 0.01 02 ---- 625 5.210 625 5.210 10 70 ISO 1.000 20 130 --4 _ 03 250 735 " 0.5 26 3.0 ---- -- 20 Capo) Mrs nhv te Appandwm *1971 Adonon **$m noia or MenM Oimpm 28 talitawe tnorthocrtsyi pnospnate Tnpnenyi phosohaie Tungsten i compounds, sw Soluble insoluble Turpentme Unnum (natural) soluble t msoiuWe compounds as U Vanadium (VtCkl as V Dust C Fume * Vaierauehyde Vmyi acetate . Vrnyt benzene, see Styrene . ... " Vmyi brombe .. .. *" VmytcMorele............. Vmyi cyande. see Aciyionenie -- Skm . Vmyi eydohexene dKme ............... Vmyadene cnorde.... Vmyt toluene............. Wartam...................... Waiding fumes (NOC)* Wood dust (nonaMergenc).......... Xylene (o-. *, p-eomms) -- Skm C m-Xyitne . a'-Wamme Xykdene -- Skm. . Yttrvun..................... Zatc efuorue turn* Zmc chromate (as Cr) . Zmc oude hene . Zmc tturst . . Zirconium compounds (as Zr|................ ADOPTED TBtTATM Will_________ VALUE! TWA STEL 9**' /*'' _ 0.1 --3 W*1 /***' _ 03 _6 -- 1 5_ 3 10 100 560 150 640 02 __ 0 5 _ 005 so ITS 10 30 20 100 (250) (AlC) 420 (1.1001 -- 150' -- (AlC) 20 45 30 10 60 10 40 20 _100 460 150 -- 01 -- 5.63 __ <_ 5 _ 100 435 _ 01 5 25 --1 --1 -- 0 0S.A2 --5 _5 150 _> 10 -- -- -- _ _ 06 15 _ 60 63__0 65 60 720 03 63 10 655 __ so 3 2 _ 10 20 10 C*0**I MwtrtMto Appenfrces *1976 Mens* "5 note* at munoad Crungn 30 SeketMM Rubber sohrent (Naphtha) Seiennart compounds (as Se) Seieneim hcuftuohde asSe Sevc* (see Carbaryi) Soane (see S*con letranydnde) Sftcon. Sifccon carbeSe Sdicon teirahydraJe (Soane) ** SiNer, metal and soluble compounds as Ag C Sodium azide Sadwm HuoroaceOte (1060) -- Sam C Sodium hydrous* Starch Srome Stoddard sofrent. Strychnme Styrene monomer (Phenylethyiene) C SuOnasms (Proteoyic enzymes as 100* pure cryaaiana enzyme) Sucrose ** SuAur ftoxtfe Sulfur heuftuonde SuAurc ac*3 SuflurmonocmorDe . Sudur pertafluonK Sulfur etrafluotde Surruryi ftuorde Systoi see Demeron* -- Sam 2 4. 5 1 Tantalum ADOPTED VALUES TWA PPT' mm*' 400 1.600 _ 02 0 0$ 04 --5 05 7 __ _i 05 0 1 (0 01) 0 1 03 005 --2 -- 0 1 OS 100 575 -- 0 IS 100 420 0 OOOOff' --c (SI (13) 1.000 -- 6.000 1 16 0 025 0 25 0 1 04 5 20 0 01 0 1 -- 10 --5 TENTATIVE VALUES ITtl ppw _ __ 005 04 _ 10 t2 __ 20 _ 20 12 _ (0.03) 015 _ __ -- 20 03 t $ 125 720 -- 0 45 125 525 -- -- 1.250 -- 3 0 075 03 10 003 -- -- 20 -- 7.500 -- 16 0 75 1 40 03 20 to Ccm 9Hm\ ir* to "Se* Mots* of nmid purges 27 lebtteue Thvam* ..................... Tm, morganc compounds, except SnH. and Sn0> (as Sn) Tm. organ* confounds (asSn)--Skm ...... Tm oude (as Sn).......... Taamum dmada (as Ti|.. Toluene (toluol} -- Skm "C Toluene-2. 4-dieocywuie flDI) .. o-ToMttne.................. Tosaphena. aae CNomaead camphene -- Stun..................... Tnbutyi phosphite....... *C t, 2.4-Tftchiorabenane 1.1. 1-TrcNoraethane. tea Methyl cfttorotomi 1.1.2-TrcMoroemene -- Skm .................. TrcMoroechyMnc.......... * TrcNoromethans. see Chiorotorm............... TnchioronapndMiene .... 1.2.3-TncMoropmpine 1.1. 2-Tnchloro t. 2. 2-traiuoroetMna .. Tnediyiamma................ Trcydoharyar hydmuda (Adran*). TnhuoromohoOromomethane ............. Trvnettyl benane .. . 2. 4.6-Tnntrophanol. see Pcrc aoo -- Sam 2.4 6-Trmfopnenyi- mcthyinaramme. see Teiryt--Skm *C2. 4 6-Trvwrowiuene (TNT).................. ADOPTED VALUES TWA mr *a _ $ ___ 100 (0 02) 5 2 01 E E 375 (0 14) 22 -- 5 350 10 100 10. A2 -- so 1.000 25 _ 1.000 25 _ 0.5 5 40 1.600 45 535 S0.A2 5 300 7.600 100 5 6.100 125 0.1 15 _ 05 TENTATIVE VALUE! 6TEL $tmr mg/*' _ 10 4 _ 02 _ 20 _ 20 150 560 __ 10 44 -- -- 440 20 ISO __ -- 75 USO 40 1.200 35 20 S -- 2.360 600 _ to 450 6.500 160 10 7.300 170 03 30 __ Cape* Mtri reMr to AMMKM 'IW Addiimn "$ Noia ot wrM CM'S** 29 i) Parts of vapor or gas par ituHen parti of contami nated air by volume at 25aC and 760 mm. Hg. pres sure D) Approumale mdi^rams of substance per cubic meter of air d) An atmospheric concentration of not more than 0.02 ppm. or personal protection may be necessary to avoid headache for intermittent exposure. e) < 7 >*m m diameter f) As sampled by method that does not collect vapor. g) for control of general room air. biologic monitoring is essential tor personnel control ffadioactrvriy- for permissible concentrations ot radio isotopes * air. see U S Department ot Commerce. Na tional Bureau of Standards Handbook 69. "Maximum Permissible Body Burdens and Maximum Permissible Concentrations of Radionuclides m Air and m Water for Occupational Exposure." June S. 1969; Addendum 1. August 1963 (NCRP Report No. 22) Also, see U S De partment of Commerce National Bureau of Standards. Handbook 59. "PermtssOU Dose from External Sources ot Ionizing Radiation." September 24. 1954. an adden dum of Apr* IS. 1956. A report. Basic Radiaton Protec tion Criteria, published by the National Committee'on Radiation Protection, revises and modernizes Die con cept of the NCRP standards ot 1954. 1957 and 1956. obtainable as NCRP Rept No 39. 7910 Woodmont Ave . Washington. 0 C 20014 Sabstence SlUCA, SiQi Crysnfit* Ouartz MINERAL DUSTS TLVmmppcf,` 300" % quartz 10 TLV for respirable dust mg/m* _________ 10 mg/m**1 % Respirable quartz * 2 TLV lor total dust, respirable and nonresptrabM 30 mg/m* % quartz + 3 31 511904 0321 CnslotJl'te . Tndymile Silica fused Tripoli 'Amorphous. .Use one-half fhe value calculated from the count or mass formulae tor quart/ Use one-naff the value calculated from formulae for quartz Use quartz formulae Use respirable" mass quartz for mula . . (20 mppcf*') SlUCATtS |< 1% quartz) *'Asbestos, all forms Mica Mineral wool fiber Perlite Portland Cement Soapstone Talc (nonasbestiform) *Taic (fibrous), use Asbestos limit 'Tremoiite, see Asbestos. (5 fibers/cc> 5**im m length-', Ala) 20 mppcl 10 mg/m1 30 mppcf 30 mppcf 20 mppcf 20 mppcf COAL OUST 2 mg/m' (respirable dust fraction < 5% quartz), if > 5% quartz, use respirable mass formula. NUISANCE PARTICULATE* (see Appendu ) 30 mppcf or 10 mg/m"' of total dust < 1% quartz, or. S mg/m' respirable dust. Conversion factors. mppcf x 36.3 Milhon particles per cubic meter particles per cc h) Millions of particles per cubic foot of air, based on impmger samples counted by Mght-field technics. i) The percentage of quartz in the formula is the amount determined from airborne samples, except m those instances in winch other methods have been shown to be applicable l) Both concentration and percent quartz for the appli es* torn o> ttimdw Oanpe 32 laMmi * Actrytsaacykc acd (Aspirin) * Acrytoneru Ahimmum metai and oxvw Alumnum pyro powders Aluminum welding lumes Aluminum, soluble salts Aluminum, atayh (NOCl* 3-Ammo 1.2 4-muoie 1 Amana and homotogues -- Sam Antimony sokftie salts las SCI Antanony moudt product** Arsanc (soluble), as As Arsenc tnoxele production * Bayiti Benomyl . Bromaci * o-sac Bury(phenol -- Skm Cadmwn oxtae product**.............. 1 Carton ftsuthde............ CNoroacetyt cMorWc... CMoromtthyi methyl ether .................... * A-Chloroprenc -- Skat .. Cobalt maul, dust 4 fume (as Co) . fC Cyanogen chlorate -. . Cyaoeenunt............... * Oaupon .. i 1.2De>romoh*ne -- Sam ................. < OcMoromonohuero- methane .. .. Ochioropropene.......... * Dwthanoiamne............ Dwayi benzene * Epchipniydfaie -- Sam TWA pew m%m*' 5 AlC Ale _ 10 --5 --5 --2 --2 A2 A2 2 10 2 _ -- A2 -- 02 _ --. Ata -- 01 -- 10 _ 10 S -- A2 10 30 0.05 0.2 Alb Alb 10 45 _ 005 0.3 06 300 150 1-- AlC Ale 10 40 15 3 15 10 SO 2 10 ITIL ppr- mms ---- _ 20 ---- ---- ---- ---- ---- 5 20 __ __ ---- __ -- 03 -- IS __ 20 _ ---- ---- _ ---- _ 0.1 ---- 450 1.000 ---- _ _ __ 10 50 ---- ---- 5 20 CuaiKWi t Men Rmsw o> AdMon 'Net owrwaa ctwiiw <**OC) 34 NOTICE OF MTEN0E0 CHANGES MINERAL OUSTS t Asbestos Amosite Chrysotiie............ Croadokte... .. Tremolite . . Other forms Duiomaceous earth. natural........... Silica, amorphous . t Talc (hbrous) 05 fiber/cc. Ala 2 tibers/cc. Ala 0 2 fiber/cc. Ata 0 5 fiber/cc, Ata 2 fibers/cc. Ala 1 6 mg/m'. Respirable dust S mg/m'. Total dust (all sampled sizes) 2 mg/m*. Respirable dust(< 5 Mm) 0.5 fiber/cc APPENDU A CAACSN08ENS The Committee ksts below those substances et in dustrial use that have proven carcinogenic m man. or have etducsd cancer n animals under appropriate tapermental conditions. Present listing of those substances carcmogemc for man takes three forms: Those for which i TLV has been assigned (la), those for winch environ mental coodrtons have not been sufficiently defined to assign a TLV (tb), and (1c). those whose reassignment of e TLV is swai&ng more definitive data, and hence should be treated as a tb carcinogen. Ala. Neman Cafdnogant. Substances, or substances associated with ndustnal processes, recognized to have carcinogenic or cocarctnogemc potential, with an assigned TLV: TLV ** Arsenic tnoxide production (AstOs. 0.05 mg/m* as As) (SCb. C5.0ppm) M$akNCMlMMO(N tlSTIMMOl 36 cation of this limil are to be determined from the fraction passing a sue-selector with the following characteristics Aerodynamic Diameter (Mm) (unit density sphere) *2 25 35 5.0 10 % passing selector 90 75 so 25 0 k) containing <1% quartz: d quartz content > 1%. use formulae for quartz l) lint-tree dust is measured by the vertical-elutnator. cotton-dust sampler described in the Transactons of the National Conference on Cotton Oust. J. R. Lynch, pg 33. May 2.1920. m) As determined by the membrane biter method at 4O0-4S0X magnification (4 mm otyacbvt) phase con trast illumination n) Based on "high volume" sampling o) "Respirable ' dust as defined by the British Medical Research Council Criteria (1) and is sampled by e device producing equivalent results (2) (t) Hatch. T E and Cross. P . Pulmonary Deposi tion and Retention of inhaled Aerosols, p. 149. Academic Press. New York. New York. 1964. (2) Interim Guide for Respirable Mass Samphng. aiha Aerosol Technology Committee. AHIA J. 31 2. 1970. p 133. NOTICE OF NfTENOED CHANGES (tor 1171) These substances, with their corresponding values, comprise those for winch either a limit has been pro posed for the first time, or tor which e change m the 'Adopted" listing has been proposed in both cases, the proposed limits should be considered trial lends that will remain <n the listing tor a period of ai least two years If. after two years no evidence comes to iqht that ques tions the appropriateness of the values herem. the val ues wilt be reconsidered for the "Adopted" list. OocumenUbon is available for each of these substances 33 TWA vra tweiari______________ w- wq/w** ppm*' wq/w**1 Ethyl sweats . r Ethylene dferorrude. see t.2-OWramoethane . * Ethylene ftchiortic. see 1.2-OKhiordsttune C Giutarsidehyee ........... Hexachipfobutadtae.... tC Hydrogen cyamde -- Sam....................... t 2-Hydrexypropyt acryttfe -Stan..................... M-lsopropytaruane -- Sfcm ................. ManqantM hene (as Mn) ...................... t Methylene cMonde (dchiorometfane)..... t 4.4-Methylene ftanWne tC2-Noprppene............. Wwnyt-beteiwphltyfemew.......... t Phoipherowi pemacmonde............ Propionc aod............. t Sever, metal............... t Sodium bttwWM............ t Sodium meufiduffee..... t Sulfur ftouM............. tC TerphenyH.................... t Tetrasodium pyrophoephme......... f Toluene-2. 4-dMocyanaie (TOl) . t Trcftloroecetc acd.. .. f Vmyl promde ........... t Vmyl tttonde ............ VM 4 P Naphtha..... 10 Ale 10 0.2 A2 10 0.5 2 -- too 0.1 25. A2 A2 0.1 10 -- -- -- 2 0.5 -- oooe -- S.A2 5. Ala 300 45 AlC 40 OS A2 10 3 10 1 360 0.1 00. A2 A2 30 01 5 5 5 S 5 0 015 1 20. A2 10. Ata 1.350 30 -- IS -- -- --- -- 5 -- 500 05 -- -- -- 15 -- -- -- 5 -- -- 0.00___6 400 250 -- 40 -- -- -- -- 20 1.700 -- -- -- 45 -- -- -- 15 -- -- 0.03___5 1.400 Caput wars n *1971 MWon 35 ** Asbestos, all forms* bis (Chloromethyl) ether Chromite ore processing (chromate) Nickel sulfide roasting, fume A dust Particulate Polycyclic Aromatic Hydrocarbons (PPAH) Vmyi Chloride (Sb0. 0.S mg/m' (as Sb|) (5 tibers/cc, > 5 Min m length) 0.001 ppm 0.05 mg/m'(as Cr) 1.0 mg/m' (as Hi) 0.2 mg/rn', as benzene solubles 5 ppm Alb. Human Cwonogens. Substances, or substances associated with industrial processes, recognized to have carcmogemc potential without an assigned TLV: Chloromethyl methyl ether 4-Ammodqihenyl (p-Xenyiamne) Benzidine production beta-Naphthytamine 4-Nitrodiphenyi Ale Human Carcntogont. Substances with recognized carcinogenic potential awadmg reassignment of TLV pending further data acquisition Acrytonttnlt 1. 2-0ibromoethane (Ethylene dibromide) For the substances m tb bf 1c. no exposure or contact by any route -- respiratory, skm or oral, as detected by the most sanative methods -- shall be permitted "No exposure or contact" means hernwtuing the process or operation by the best practicable owing mrtwds Tiw wornet siwuid b* preport* equipped to insure virtually no contact with the carcmogen Cqu mutt can vmw * ncamca oc**art hem m and oawn ti raw sueraw* o* pwewaw 37 511904 0322 A2 moustnai Substances Suspect ot CaranogmK Po tential for MM Chem<a< substances or substances associated with industrial processes, which are suspect ot mducmg cancer, based on either (i) limned epioemiotogic evidence exclusive ot ctmcai reports ot single cases or (2) demon stration ot carcinogenesis in one or more animal species by appropriate methods 3-Ammo 1.2 4-tnuole * Antimony tnoiide production* Benzene Benzia)pyrene Beryllium ' * Cadmium oxide production Chloroform Chromates of lead and nnc (as CO 3. 3 -Dichiorobenzidine Oimethylcarbamyi chloride 1 1 -Dimethyl hyorazme Oimethyi sulfate -- Stun EpiChlorhydrm Hexachiorooutadtene Hexamethyi phosphoramide -- Skin Hydrazine Lead chromate 4. 4'-Methyiene bis (2-chtoroamlme) -- Skm Monomethyl hydrazine C2-Nitroproparx Nitrosammes Phenyf-beta-naphthytamme Propane suttone bela-Proptolaclone Vmyl cyctohexene dioxide Zinc chromate (as CO (0.S mg/m3) 1C ppm -- 2 0*g/m3 (0.05 mg/m3) 10 ppm 0.05 mg/m3 -- -- 0 5 ppm 0 1 ppm 5 ppm 0 1 ppm 0 05 mg/m3 0 02 ppm 0.2 ppm 25 ppm -- ---- -- -- 10 ppm 0.05 mg/m3 For the above, worker exposure by alt routes should be carefully controlled to levels consistent with the animal and human experience data (see Documentation). including those substances with a listed TLV 'C$***i ynoutg can munu We dcxm tt rapraory canctu from vus v oexa ot eww tuMunos w procntn 3d A3 Gmdetem for the Oaurhcaoon of Experiment* ANIMAL Cercmogens The following guidehnes are ottered in the present state of knowledge as an aid n classifying substances in the occupational envi ronment found to be carcinogenic m experimental animals A need was felt by the Threshold Limits Committee for such a classification m order to take the first step m developing an appropriate TLV tor occupational exposure. Determination of Approximate Threshold of Re sponse Requirement. In order to Oetermne m which category to classify an experimental carcin ogen tor the purpose of assigning an industrial air limn (TLV). an appronmate threshold of neoolashc response must be determined Because of practi cal experimental drfficuities. a precisely defined threshold cannot be attained For the purpose* of standard-setting, uus is of trifle moment, as an ap propriate nsk. or safety, factor can be applied to the approamate threshold, the magnitude of which is dependent on the degree of potency of the car cinogenic response. To obtam the bast practical' threshold of neoplas tic response, dosage decrements should be less than logarithmic This becomes particularly impor tant at levels greater than to ppm (or correspondtg mg/m') Accordingly, after a range-finding de termination has been made by logarithmic decreases, two additional dosage levels are re quired within the levers of' effect' and no effect'' io approumate the true threshold of neoplastic re sponse The second step should attempt to establish a me tabolic relationship between antmai and man lor the particular substance found carcinogenic m an imals ir the metabolic pathways are lound compa rable the substance should be classed highly suspeci as a carcinogen lor man It no suen relation is found me substance should remain listed as an experimental antmai carcinogen unoi evidence to me contrary is found Proposed ClassdKiOon of Experimentat Animal Caronogans Substances occurring m the occupa tional environment found carcinogenic for animals 39 may be grouped into three classes, those of high, intermediate and low potency In evaluating the in cidence of animal cancers, significant incidence of cancer rs defined as a neoplastic response wnich represents, in the judgment ot the Committee, a significant excess of cancers above that occurring in negative controls EXCEPTIONS No substance is to be considered an occupational carcinogen of any practical signifi cance which reacts by the respiratory route at or above 1000 mg/m1 lor the mouse, 2000 mg/m1 for the rat. by the dermal route, at or above 1500 mg/kg for the mouse. 3000 mg/kg tor the rat. by the gastrointestinal route at or above 500 mg/kg/d for a lifetime, equivalent to aoout 100 g T.O for the rat. lOg T D for the mouse These dosage limitations exclude such substances as dioxane and trichioretnytene from consideration as carcinogens Examples. Oioxane -- rats, hepatocellular and nasal tumors from 1015 mg/kg/d, oral Trichloroethylene -- female mice, tumors (30/98 < 900 mg/kg/d), oral A3a INDUSTRIAL SU8STMCES Of HIGH CAfiCHQGENIC POTENCY IN EXPERIMENTAL ANIMALS 1. A substance to qualify as a carcinogen of high potency must fulfil one ot the three following conditions n two animal species: la. Respiratory Eliot cancer from (1) dosages below 1 mg/m3 (or equivalent ppm) via the respiratory tract m 6- 7-hour daily repeated inhalation exposures throughout Wetime; or (2) from a single imratracheaiiy admin istered dose not exceeding 1 mg of parti culate. or liquid, per 100 mt or less of an imal minute respiratory volume. Examples* bis-Chioromethyl ether, mahgnant tumors, rats. @ 0.47 mg/m> (0.1 ppm) m 2 years: 40 hexamethy! phosphoramide. nasal squamous cell carcino ma. rats. @ 0 05 ppm. in 13 months OR 1b Dermal Elicit cancer withm 20 weeks by skin-painting, twice weekly at 2 mg/kg body weight or less per application tor a total dose equal to or less than 1.5 mg. in a biologically inert vehicle. Examples 7. 12-Dimethytbenz(a)anthracene -- skm tumors <@ 0.120.8 mg T.O. four weeks Benz(a)pyrene. mice 12 mQ. 3X/wk tor 18 mos. T O. 2.6 mg. 00.9% stun turnon OR 1c. Gastnmiestinaf Elicit cancer by daily in take via the gastrointestinal tract, withm six months, with a six-month holding period, at a dosage below 1 mg/kg body weight per day; total dose. rat. * SO mg. mouse. 3.5 mg: Examples. 7. 12-Oimethyibeiu(a)anthra cene -- mammary tumors from 10 mg IX 3-Methylcholanthrane -- Tumors @ 3 sites from 8 mg m 89 weeks Benz(a)pyrene. mice. 3 9% leukemias, from 30 mg T.O. 198 days 2. Elicit cancer by all three routes m at least two animal species at dose levels prescribed tor high or intermediate potency. A3b. INDUSTRIAL SUBSTANCES Of INTERMEDIATE CARCINOGENIC POTENCY IN EXPERIMENTAL AN IMALS To qualify as a carcinogen of intermediate potency, a substance should Not cancer m two animat spe- 41 cks at dosages intermediate between those de scribed m A3a and Me by two routes ot admimstrabon Example Caroamic acid ethyl ester Dermal, mammary tumors, mice, 100%. 63 weeks. 500-1400 mg T D. Gastrointestinal, various type tumors, mice 42 weeks. 320 mg T 0 Gastromtestinai. various type tumors, rats. 60 weeks. 110-930 mg T 0 A3c INDUSTRIAL SUBSTMCES Of LOW CARCINO GENIC POTENCY IN EXPERIMENTAL ANIMALS To qualify as a carcinogen of low potency, a sub stance should elicit cancer m one animal species by any one of three routes of administration at the toUoxnng prescribed dosages and conditions. la. Respiratory Elicit cancer from (1) dosages greater than 10 mg/m' (or equivalent ppm) via the respiratory tract m 6- 7-hour, daily re peated mhaianon exposures, lor 12 months' exposure and 12 months observation period, or (2) from eitratracneaiiy administered dos ages totaling more than 10 mg of particulate or hquid per 100 ml or more of animal minute respiratory volume; Examples Beryl (beryllium aluminum sacate) malig lung tumors, rats. @ 15 mg/m3@ 17 months Benzidine, var. tumors, rats. 10-20 mg/m'@ > 13 mos. OR lb. Dermal Eliot cancer by skm-pamong of mice in twice weekly dosages of > 10 mg/kg body weqjhi in a biotogtcafiy nert vehicle for at least 75 weeks, i.e , * 1 Sg T.O Examples' Shale tar. mouse. 0 1 ml * SO gT.D 59/60 stun tumors Arsenic trtoxide. man. dose un known. but estimated to be high 1c Gastromtesonaf. Elicit cancer from deity oral 42 dosages ot 50 mg/kg/day or greater during the lifetime of the animal APPENDIX I SUBSTANCES Of VARiAtlf COttPOSfTION 61 Polytetratiuoroethyiene* decomposition products Thermal decomposition ot the fluorocarbon chain m an leads to the formation of oxidized products con taining carbon fluorine and oxygen Because these products decompose xi part by hydrolysis m atkalxie solution, they can be quantitatively determined in air as fluoride lo provide an moei ol exposure No TLV is recommended pending determination of the toxicriy ot the products, but ax concentrations should be minimal B2 Gasohne The composition ot gasoline vanes greafly and thus a smgie TLV tor all types of these materials s no longer applicable. In general, the aromatic hy drocarbon content wXI determine what TLV applies. Consequently the conteni of benzene, other aromat ics and additives should be determined to strive at the appropriate TLV (Elkins, et al A l.H a.j 24.99, 1963): Rumon. ibid. 36. 338.1975) B3 Wefdmg fumes -- Total PatbcMta tNocr TLV 5mp/m> Welding fumes cannot declassified simply The com position and qusntiry of both are dependent on the alloy being welded and the process and eleettodes used Reli able analysis of lumes cannot be made without consider ing me nature of the welding process and system being examined, reactive metals and alloys such as aluminum and titanium are arc-welded m a protective men atmo sphere such as argon These arcs creaie relatively iittu fume but an miense radiation which can produce ozone Simitar processes are used to arc-weld sleets, also creating a relatively low level of fumes Ferrous alloys also are arc-weided m oxidizing environments which generate considerable fume, and can produce carbon monoxtoe mstead of ozone Such fumes geneiaiiy are composed ol discreef particles of amorphous stags con- 'tiMttuwm JMqoHon two" "hoi omwww emteme ihOCi lew tu*i 43 511904 0323 uming non. manganese, silicon and other metallic con stituents depending on tne moy system involved Chro mium and nickel compounds are found x fumes when sumiess steels ate arc-welded Some coated end fluxcored electrodes are formulated with fluoride! and the fumes associated with tnem can contain significant more Nuonoes man oxides Because of the above fac tors arc-weidmg fumes frequently must be tested for individual constituents whicn are inteiy to be present lo determine whether soecitic Tiv s are exceeded Conclu sions based on total fume concentration are generally aoequaie if no toxic elements are present ei welding rod. metal, or metal coating and conditions are not conducive to the lormabon of toxic gases Most welding, even with primitive ventilation, does not produce exposures inside me welding helmet above 5 mg m* That which does, should be controlled. APPENDIX C MIXTURES C 1 THRESH010 LIMIT VALUES FOR MIXTURES When two or more hazardous substances are pres ent. their combined effect, rather than mat of either indi vidually. should be given primary consideration. In the absence of information to the contrary, the effects of the different hazards should be considered as additive. That is. if the sum of the following fracftons. il _J- Tt T, - T. exceeds unity, then the threshold Urnit of the mixture should be considered as being exceeded. & indicates me observed atmospheric concentration, and Ti the cor responding threshold hmit (See Example 1A.I. and 1Ac) Exceptions to the above rule may be made when there is a good reason to believe that the chief effects of me different harmful substances are not m fact additive. Out independent as when purely local effects on different organs of me body are produced by the various compo nents of the mixture In sucn cases the threshold limit ordinarily is exceeded only when at least one member of Example No 1A a Air contains 400 ppm of acetone (TiV * 1000 ppm) ISO ppm of secbutyf acetate (TLV 200 ppm) and 100 ppm of 2-butanone (TLV - 200 ppm) 400 tso 1000 * 200 Atmospheric concentration of mix ture 400 * ISO 100 650 ppm of mixture too 200 04 + 0 75 + 05* 1.65 Threshold Limit is exceeded. Mb Special case when tne source of contaminant a a hquid mixture and the atmospheric composition ts assumed to be simitar to that of the original matenai. e g on 1 time-weignied average exposure basis, an of the liquid (solvent) mixiute eventually evaporaies. Additive effects (approximate solution) 1 The percent composition (by weight) of the liquid mixture is known, the TLV$ of the constituents must be listed in mg/m*1. (Mote In order to unbelt comptonce mth Bus TLV, he/d tempting instruments should be ctibreted. m the laboratory, tor response to this specrtc guentitetne end quehtetve airvapor mature, end e/so to trecbonel concenmoons 01 Mrs mixture, e g . U2 Me TLV; 1110 the TLV; 2 x the TLV; 10 * the TLV; tK.) TLV of mixture 1 _fj_ _l_ TLV. * TLV* * TLV, * f. TLV. Example No 1. Liquid contains (by weight) 50% heptane TLV - 400 ppm or 1600 mg/m1 1 mg/m3 * 0 25ppm 30% methyl chloroform TLV - 350 ppm or 1900 mg/m1 1 mg/m1 0 26 ppm /Ci Ci \ ihe senes I+ or etc.l itself has a value exceeding unity (See Example 1A c ) Antagonistic action or potentiation may occur with some comomabons of atmospheric contaminants. Such cases at present must be determined individually Poten tiating or antagonistic agents are not necessarily harmful by themselves. Pofkntiaung eflecu of exposure to such agents by routes other than that of inhalation is also possible, e g imbibed alcohol and mhaied narcotic (trichloroethylene) Potentiabon is cheractensticaJiy exhi bited at high concentrations, less prooabiy at low When a given operation or process characteristically emns a number of harmful ousts, fumes, vapors or gases, it writ frequently be only feasible to attempt to evaluate tne hazard by measurement of a single sub stance In such cases, the threshold kmrt used tor this substance should be reduced by a suitable factor, the magnitude of which wilt depend on the number, toxicity and rotative quantity of the other contaminants ordnanty present. Examples of processes which tre typically associated with two or more harmful atmospheric contaminants are welding, automobile repair, blasting, painting. lacquer ing certain foundry operations, diesel exhausts, etc. CMixemobs 0/ THRESHOLD UktfT VALVES FOR MIXTURES The following formulae apply only when the compo nents in a mixture have similar toxicologic effects, they should not be used for mixtures with widely differing reactivities, e g hydrogen cyanide A sulfur dionde in such case the lormula for independent Effects (lA.c.) should be used 1A a General case, where air is analyzed for each com ponent a. Additive effects. (Mote A a tssentiel Mat Me atmosphere be analyzed both guaMaffve/y end QuvuitiOvtty tor each component present, m order to nbote comphence or noncom pliance wrffi Mis caJcuJafttf TLV) C. G> ^ Cj 45 2(7% pereffloroemytene: nv - 100 ppm or 670 mg/m1 1 mg/m* 0.15 ppm TLV of Mixture - 02 670 10 1300 mg/m1 of this mixture 50% or (1300) (0.5) " 650 mg/ma a heptane 30% or (1300) (0 3) 390 mg/m* a methyl chloro form 20% or (1300) (0.2) - 260 mg/m* a perchtorocthyiene These values can be convened to ppm as tohows: heptane 650 mg/m1 * 0 25 - 162 ppm methyl chloroform. 390 mg/m1 * 0.16 70 ppm perchioroethyiene 260 mg/m1 * 0 15 39 ppm TLV of mixture 162 * 70 39 - 27l ppm. or 1300 mg/m1 He Independent effects Air contains 0 15 mg/m1 of lead (TLV. 0.15) and 0 7 mg/m1 of sutfunc acid (TLV. 1) 0-15-1. 0.15 JLL.07 1 Threshold bmrt 6 not exceeded 16 TLV for Mixtures of Mineral Dusts. For mixtures of biologically active mineral dusts (ha general formula for mixtures may be used For mixture containing 60% nonasbestiform utc and 20% quartz, lha TLV tor 100% of the mixture ts given by TLV t 06 , 02 20 2 7 9 mppcf TLV of nonasbestilorm talc (pure) 20 mppcf 47 Tlv of quartz (pure) 300 a 300 100 - 10 11O 2.7 mppcf Essentially the same result will be obtained it me lenit of tne more (mosl) tone component is used provided the effects are adoibve. in the above ex ample the limit tor 20% Quartz is 10 mppcf For another mixture of 25% quartz. 25% amor phous silica and 50% late 25% quartz -- TLV (pure) -27 mppcf 25% amorphous silica -- Tiv (pure) mppcf 50% Uic TLV (pure) > 20 mppcf TLV 1 6 mppcf 0 25 , 0 25 , 0 5 2 7 20 20 The hmif tor 25% quartz approximates 9 mppcf. APPENOIX D PCRMiSSMU EXCURSION! FOR TIME- WEtOHTEO AVERAGE (TWA) UMIT! The Excursion TLV Factor i the Table automatically defines the magnitude of the permissible excursion above the hmit for those substances not given a "C" designation, r e . tne TWA krmts. Examples *1 the Table show that nitrobenzene.' the TLV for which a 1 ppm. should never be allowed to exceed 3 ppm Similarly, carbon tetrachloride. TLV - 10 ppm, should never be allowed to exceed 20 ppm. By contrast, those sub stances with a "C" designation arc not subiect to the excursion factor and must be kept at or below the TLV ceiling These tanning excursions are to be considered to provide a "rute-of-thumb" guidance for fisted substances generally, and may not provide the most appro priate excursion for a particular substance e g . the per missible excursion lor CO is 400 ppm for 15 minutes For appropriate excursions for 142 substances con sult Pa Rules A Regs . Chap 4. Art. 432. and "Accept able Concentrations." ANSI 46 Substance Nitrobenzene Carbon tetrachloride Tnmethyl benzene Acetone Boron influortde Butyiamme Mu Cone. Permitted Excursion for short TLV Factor time t 10 25 1000 Cl C5 3 2 1.5 1.25 -- 2 20 35 1250 t 5 EXCURSION FACTOR! For ail substances not bearing C notation TLV>0-1 (ppm or mg/m1). TLV> t-tO TLV> 10-100 TLV> 100-1000 Excursion Factor 3 -2 - 1.5 * 1 25 The number of times the ctcursion above the TLV a permitted is governed by conformity with Me Time* Wwghted Average TLV. INTERPRETATION OF MCAAUREO PEAK CONCENTRATIONS With mcreasmg use of rapid, direct-reading analytical instruments for airborne contaminants m the work area, the question of interpretation of essentially ' instanta neous" peaks arises Although no general statement can be made covering ad occupational substances, the fol lowing guidelines should prove helpful, assuming peak excursions conform 10 time-weighted average Tlv as stated above The toxicologic importance of momentary peak con centrations depends on whether me substance fast or slow acting If slow acting as tor quartz, teed, or car bon monoxide, momentary peaks are of no toxicologic concern provided, of course, they are not astronomic On (he other Band, fast actmg substances that rP`Pn' produce dtsabhng narcosis, e g . Hi S. or intolerable tauon or asphyxiation. Ntfc. SO*. C(N. or inmate sensitiza tion -- the organic isocyanates, even "instantaneous peaks appracUbiy above the permissible excursion, should not be permitted, unless ^formation exists to the 49 511904 0324 contrary Offr more specific excursions will be develOOfd mine tuture. APPENOR I Some ftetsame ParMalater1 TLV. 30 mppcl or lOmg/m1 ol total Oust < 1% quartz or. 5 mg/m3 respirable Oust AlunOum (AbOs) Calcium carbonate Caicum sdicate Ceuio$e (paper fiber) Portland Cement Corundum |Ab Oi) Emery Giycenn Mtsl Graphite (synthetic) Gypsum Vegetable ort mists leicept castor cashew nut. or similar irritant oils) Kaoim limestone Magnesite Marble Mineral Wool Fiber Pentaerytnritoi Plaster ot Pans Rouge Silicon Silicon Carbide Starch Sucrose Tin Oxide Titanium Dioxide Zmc Stearate Zmc o0e dust p) When toxic impurities are not present, e g. quartz < APPENOR F Seme Simple AapAyxtantr1 Acetylene Argon Butane Ethane Ethylene Helium Hydrogen Methane Neon Propane Propylene q) As defined on pg 6. APPEMOR G Calculations for Conversion of Partide Count Concen tration (by Standard light Fietd -- Midget Impmger Techniques), in mppcf. to Respirable Mass Concentra tion (by Respirable Sampler) m mg/m3 * ftri*iofls* Betwtf" Gwmcirc Acte****D2ust Concrniriw r*j M9i moQe' ihmtw* Omcmi'Bv* by Muir* Jacobian me ' f Tomb Aihaj ft Hon-Ott i%t 50 In 1967. Jacobsen and Tomb,* denved an empiri cal relationship of 5 6 mppcf to 1 mdtqram of respirable dust per cubic meter or air. based on 23 sets ot samples, mostly coal dust The follow ing calculation results in an equivalence of 6.37 mppcf to 1 mg/m* of respirable dust Thus, an approximate ratio ot 6 mppet to 1 mg/m* of re spirable dust is suggested tor conversion of TIVs from a count to a mass basis when the density and mass median diameter have not been deter mined 2 Basic assumptions. a) Average density for silica containing dusts 2 5 gm$/cm3 (2500 mg/cm*) Pulmonary sig nificant dust densities may vary from 1.2 gm/cm* for coal dust lo 3 1 gms/cm* for Portland Cement Siica densities vary from 2 2 (amorphous) to 2.3 (cnstobaMe and Indymite) to 2 5 (alpha-quartz.) gms per cm*. b) The mass median diameter (mmd) of particles collected m midget impinger samplers and counted by the standard light field technique, and collected m a respirable sampler is ap proximately l 5 Mm oil 5 * 10'* cm This assumption ts. ot course, qurte arbitrary since the mmd ot aft dust clouds is quite variable, depending on many independent parameters, such as source ot dust, age ot dust cloud, me teorological conditions, etc 3 Calculation a) voi per particte 4/3 t r*. f 0 75 * 10'4 cm 4/3* w M0 75 * 10**)* - 1 77 * 10 '* cm3 b) wt per particle vd * density a i 77 x 10'13 cm* * 2 5 x to* mg/cm3 4 425 x 10'* mg/pariicte c) 1 panicie/ft3 35 5 part /m (smee 35 5<u ft 1 cun' ) 10* pan /ft3 = mppcf - 35 5 x to* part /m3 51 *t of 1 mppcf 35 5 * 10* pett./m* x 4 425 x 10* mg/part i mppcf 0.157 mg/m* or 6.37 mppcf* 1 mg/m* or approsmaiety 6 mpccf mg/m*. 1 4. Equivalent TIVs in mppcf and mg/m* (respirable mass) for Mmerat Dusts. SJ0stance Threshold limit Value Count Resp. Mass Total Mass* mppcl mo/m* mo/m* Siha (SiOtt Amorphous Cristobaiftt Fused sritea Quartz Tridymite Coat Dust Oiatomaceous earth, natural Graphite (natural) Mia Mineral wool fiber Nuisance particulate Pertit* Portland Cement Soapstone Talc (nonasbestiform) Tripoli 20 IS 3 3 1.5 (12) IS 20 -- 30 30 30 20 20 (3) (3)" 005 0.1 0.1 0.05 2 1.5 (2.5) (3) (5) (51 (5) (5) (3) (3) 0.1 (6) 0.15 0.3 0.3 0.15 ) (5) (6) 10 10 (10) (10) (6) (6) (0.3) `Una omwi menu wenan irm ewrw to wuf wpraunaM|r 50% or mal mas. ,4ai saw o Mmwia ( ) mersan im* aiumm nks base on aoumwer r mood m I mg/m4 raieob* man aW wokSit mas 50% lota mas 52 511904 0325 PREFACE FHY8CAL AGEMTS These threshold limit values refer to levels of physical agents and represent conditions under which it is be lieved that nearly an workers may be repeatedly exposed day after day without adverse eflect Because of wide variations m individual susceptibility, exposure of an oc casional individual at. or even below, the threshold tamil may not prevent annoyance, aggravation of a pre-exist ing condition, or physiological damage These threshold limits are based on the best tradable information from industrial experience, from experimen tal human and animal studies, and when possible, from a combination of the three. These limits are mended for use m the practice of industrial hygiene and should be interpreted and applied only by a person trained m this discipline. They are not intended for use. or tor modification for use. (1} in the evaluation or control of the levels of physical agents in the community. (2) as proof or disproof of an casting physical disability, or 0) for adoption by countries whose woriung conditions differ from those i the United Stales of America. These values are reviewed annuahy by IN Committee on Threshold Limits for Physical Agents lor revisions or additions, as further mformation becomes available. Notice of Intent -- At me beginning of each year, proposed actons of the Committee for the forthcoming year are issued m the form of a "Moocc of intent." Th notice provides not only in opportunity tor comment, but solicns suggestons of physical agents to be added to the list. The suggestions should be accompanied by substantiating evidence As Legislitm Code -- The Conference recognizes that the Threshold Unit Values may be adopted m legis lative codes and regulations If so used, the aitent of the concepts contained m the Preface should be maintained and provisions should be made to keep the list current. 55 Peprmt Permission -- This publication may be re printed provided that written permission is obtained from the Executive Secretary of the Conference and that this Preface be published m its enorety along with the Threshold limit Values THRESHOLD UMfT VALUES HEAT STRESS These Threshold Umrt Values refer to heat stress conditions under which it is believed that nearly Ml workers may be repeatedly exposed without adverse health effects. The TLVs shown in Table 1 are based on the assumption that nearly aH acclimatized, fully domed workers with adequate water and sMt intake should be able to function effectively under the given working con ditions without exceeding a deep body temperature of 3TC (WHO techmcM report series #412. 1969Nea/tft Fictors InroiveO tt Worktop Under ConOitons of Hut Stress, F N. Oukes-Oobos and A Henschel. "Oevehfh ment of Permissible Hut Exposure Umits hr Occupa tion*1 Wort - ASHRAE Journal. Vot IS No 9. Sep tember 1973. pp S7-62 ) Since measurement of deep body temperature is im practical for monitoring the workers heat load, the mea surement of environmental factors is required winch most nearly corretale with deep body temperature and other physiological responses to neat Ai the present time Wet Bulb-Globe Temperature Index (WBGT) is the ^molest and most suitaoie technique to measure tne en vironmental factors WBGT values are cMcuiated by the following equanons > Outdoors with solar load WBGT - 0 7W8 - 0.2GT 0 1 OB 2 indoors or Outdoors with no solar load WBGT - 0 7W8 0 3GT where WBGT - Wet Bulb-Globe Temperature Index W6 - Natural Wet-Bulb Temperature 06 Dry-Buto Temperature GT - Globe Thermometer Temperature 56 The determination of WBGT requires the use of a black globe thermometer, a natural (state) wet-butt thermom eter. and a dry-bulb thermometer TABLE 1 Permissible Heat Exposure Threshold Limit Values (VMues are given in *C. WBGT) Work Load Work -- Rest Regimen Light Moderate Heavy Contnuous work 300 26 7 25.0 75% Work -- 25% Rest, Each hour 30.6 280 25.9 50% Work -- 50% Rest Each hour 31.4 29.4 27.9 25% Work -- 75% Rest, Each hour 32.2 31.1 30.0 Higher heat exposures than shown at Table 1 are per missible if the workers have been undergoing medcaJ surveillance and rt has been established that they are more tolerant to work m heat than the average worker. Workers should not be permitted to continue their work when the* deep body temperature exceeds 38.(TC. EVALUATION AND CONTROL I. IlMsummertf of (he im/tronment The mstmments required an a Wy-bulb. a uturM wet-bufb. a globe thermometer, and a stand. The mea surement of the environmcntM factors shall be per formed as follows: A. The range of the dry and the natural wet bulb ther mometer that! be -5`C to SO*C wtth an accuracy of *0.5*0. The dry bulb thermomettr must be shielded from the sun and the other radiant surfaces of the envi ronment without restricting IN airflow around the butb. The wick of the naturei wet-buib thermometer sftati be 57 kept wet with distmed water for at leut 112 hour before the temperature reading is made ft is not enough to immerse the other end of the wick imp a reservoir of distilled water and wait until the whole wick becomes wet by capillarity The wick snail be wetted by direct application of water from a syringe 1/2 hour before each reading The wick shall extend over the bulb of the ther mometer. covering the stem about one addibonM bulb length The wick should always be clean and new wicks should be washed before using. B A globe thermometer, consisting of a IS cm (6* tnch) diameter ngifow copper sphere painted on the outside with a matte black finish or equrvaient. shall be used The bulb or sensor of a thermometer (range - S*C to I0CTC with an accuracy ot 0.$*C) must be fixed in the center ot the sphere The globe thermometer siuii be exposed at least 2S minutes before it is read. C. A stand shall be used to suspend the three thermom eters so thtt they do not restrict free air flow around the bulbs, and the wet-bulb and globe thermometer are not shaded 0 It a permissible to use any other type ot temperature sensor that gtves identical reading as that of a mercury thermometer under the same conditions E The thermometers musl be so placed that the read ings are representative of the condibon where the men work or rest, respectively The methodology outlined above is more tutty ex plained m the following publications 1. "Prevention of Heat Casualties m Mamie Corps Re cruits. 1955-1960. with Comparative Incidence Rates and Climatic Heat Stresses m other Training Catego ries." by Captain Oavid Mmard. MC, USN. Research Re port No 4 Contract No MR005.0V-0001 01. Naval MedicM Research Institute. Bethesda. Maryland. 21 Feb ruary 1961 2 "Heat Casualties in the Navy and Marine Corps. 1959-1962. with Appendices on the Field Use of the Wit Bulb-Globe Temperature index." by Captain Oavtd Mmard. MC. USN. and R L O'Brien HMC. USN. Re search Report No 7. Contract No MR 005 OVOOOI 01. NavM Medial Research Institute. Bethesda. Maryland. 12 Mvtt 1964 58 3 Mmard. 0 . Prevention of Heat CasuMties r Marine Corps Recruits Mdrtary Medicine 126(4) 261-272 1961 It Work loitf Cl(agones Heat produced by the body and the environmental heat together determine the total heat toad Therefore, if work is to be performed under hot environmental condi tions. the workload category of each pb shall be es tablished and the heat exposure hmit pertinent to the work toad evMuated against the applicable standard m order to protect the worker from exposure beyond the permissible Umrt A The work toad category may be established by rank ing each fob mto light, medium, and heavy categories on the basis of type ot operation. Where me work toad ts ranked mto one of sari three categories. i.e. (1) hght work (up to 200 KcM/hr or 800 Btu/hr). e g . sithng or standing to control machines, performing hght hand or arm work. (2) moderate work (200-350 Kcal/hr or 800-1400 Btu/hr). e.g.. walking about with moderate Mung and pushing. (3) heavy work <350-500 Kcal/hr or 1400-2000 Btu/hr): e.g.. pick and shovel work, the permissible heat exposure lend for that work toad shMi be determined from Table 1. 8. The ranking of the pb may be performed either by measuring the worker s metabolic rate whde performing Ms pb or by estimating his metabolic rate by the use of the scheme shown in Table 2. Tables araiabto m the Merature ksted below and in otter publications as wei may atso be utrised. When ties method is used the per missible heat exposure hmit can be determined by Figure 1 1 Per-Otaf Astrand and Kaare RodalU: "Textbook of Work Phystotogy" McGraw-HdJ Book Company. Mew York. San Francisco. 1970. 2. "Ergonomics Gutoe to Assessment of Metabolic and Cardiac Costs of PhysicM Work." Amer. Ind. Hyg. Assoc. J.32. 560,1971. 3. Energy Requirements tor Physical Work. Purdue 59 Farm Cardiac Protect. Agricultural Expenmwit Station. Research Progress Report No. 30.1961. 4 j V.G A. Dumm and R. Passmore "Energy. Work and leisurt " Hemimann EducattonM Books, Ud.. Lon don. 1967 / TABLE 2 Assessment of Wott Load Average values of metabolic rate durmg different sctwites. A. Body position and movement Sitting Standing Waking WMtonguphifi Kcal /mm. 03 06 2 0-3 0 add 0.8 per meter (yard) rise B. Type of Work Average Range KcM./mm KcM./mm Handwork hght heavy Work with one arm light heavy Wotk with both arms hght heavy Work with body hght moderate heavy very heavy 04 0.9 1.0 1.8 1.5 2.5 3.5 SO 7.0 90 0 2-1.2 0.7-25 1.0-3.5 2 5-15.0 Ught hand work wrung, hand kmRing Hewy hand work: typewriting Heavy work with one arm: hammering In nails (shoe- makar. upholsterer) Ughi work with two arms: filing metal, pianino wood, raking of a garden 60 511904 0326 Moderate wort with the body cfoinmg a floor, beatmg a carpet Heavy work with the body, railroad track laying. dig* gmg. banung trees Sample Calculation Using a heavy hand toot on an assembly ime A Walking along 2.0KcaUmn. 6 intermediate value between heavy work with two arms and fignt work with the body 3 0 KcaUrtun. C Add tor basal metabolism 5 0 Kc*./mm. 1 0 Kcal./mm. Total 6.0 Kcai./min. Adapted from Lehmann. 6. E., A. Muller and H Sprtzer: Oer Kaionenbedarf bei gewerblicher Arbeit. Arbetsphysol. t4 166. I960. HI. Work'RntRiguim The permtssftle exposure hmrts specified at Table 1 and Figure i are based on the assumption (hat the W6GT value ot the resting place is the same or very dose to that ot the work place Where the WBGT of the work aree is different horn that of the rest area a timeweighted average value should be used tor both environ mental and metabolic heat When time-weighted average values are used the appropriate curve on Figure 1 is the solid tme labeled "continuous.'' The time-weighted average metabolic rate (M) shall be determined by the equaton. Av M (Mi)x<t,> + <M)*(t>+. +(*!.} *.) <li>-(b)*.. + <U Where Mi Mt. M, are estimated or measured metabolic rates tor the various achvmes of the worker during the total time period ti. b. L are the elapsed times m min utes spent at the correspond** metabolic rate as deter mined by a time study The time-weighted average WBGT sh*l be deter mined by the equation. 61 Av WBGT IWBGT.) x |t,) (WBCTa) x b (WBGT.) * It.) (W - <bl * IU where WBGTi. WBGT], WBGT. are calculated values ot WBGT lor tne various work and rest areas occupied dur ing total time periods ti. b, L are tne elapsed times in minutes spent m the corresponding areas which are de termined by a time study Wheie exposure to hot envi ronmental conditions is continuous for several hours or the entire work day. the time-weighted averages shall be calculated as hourly time-weignted average i e . ti b t, 60 minutes Where the exposure is intermit tent the time-weighted averages snail be calculated as two-hour time-weighted averages, i e ti b + . . . t. 120 minutes The permissible exposure limits tor continuous work are applicable where there is a work-rest regimen of a 5-day work week and an 6-hour work day with a short morning and afternoon break (approximately IS min utes) and a longer lunch break (approximately 30 min utes) Higher exposure limits are permitted if additional resting time is allowed All breaks including unsche duled pauses and administrative or operation* waiting periods during work may be counted as rest time when additional rest allowance must be given because ol high environmental temperatures. It is a common experience that when the work on a too is seh-paced. the wotkets w>u spontaneous*? hmn their hourly work load to 30-50% ol then maximum physical performance capacity They do this either by setting an appropriate work speed or by interspersing unscheduled breaks Thus the daily average of the workers' metabolic rate seldom exceeds 330 kcal/hr However, within an 8-hour work shift there may be periods where the workers' hourly average metabolic rate wdl be higher IV Water ana Sail Supplementation Ourmg the hot season o< when the worker is exposed to artificially generated heat drinking water shall be made available to me workers m such j way thai they are stimulated to frequently dunk small amounts i e one cup every 16-20 minutes (about >50 ml or 1/4 pint) 62 The water shell be kept reasonably cool (10"-15" C or SO O'-60 (TF) end shall be pieced dose to the work place so mat me worker can reach it without abandoning the work area The workers should be encouraged to salt lh*r food abundantly during the hot season end particular* during hot spells if me workers ere unecetimetized. salted drinking water shaM be made available m a concentration of 0 1% (ig NaCl to 1 0 liter or 1 level tablespoon ot sen to IS quarts of water) The added salt shall be complete ly dissolved before the water is dstnbuted. and me water shall be kept reasonably cool. V. Other Consrtertoons A Clothing: The permtssiMe heat exposure TLVs are valid tor light summer dothing as customarily worn by workers when working under hot environmental condi tions if special earning is requeed tor performing a par ticular job and tins ttothmg ts heavier or a impedes sweat evaporation or has higher insulation value, the worker's heat tolerance is reduced, and the permissible heat exposure hmits mdeated m Table 1 and Figure 1 ire not applicable. For each 106 category where special doming i$ required, the permissible heat eposura Ime shall be established by an expert. B Acclimatization and Fitness The recommended heat stress TLVs are vtd for eedmetod workers who ere physically tit 63 Ft|wi 1 -- Ptimtutta Heat Exposure Thrashou Um V*ue 64 KNKBM tMUftTKM The recommendations of me Nation* Councrt on Radia tion Protection and Measurements (NCRP) are suggest ed as threshold finut vakies to which near* all workers may be exposed without adverse effects. The hmits should be used as guides tor the control of exposure and should not be regarded as fine fines between sate and dangerous levels. The underlying philosophy of radi ation protection * to keep ad exposures as low as raasonabiy achievable. The two basic rtferwica documents are as follows: a. " Basic Radiation Protaction Catena." NCRP Re port No. 39. issued January IS. 1971. b ''Maximum Permissible Body Burdens and Max imum Permissible Concentrations of Radionuclides m Air and m Water tor Occupation* Exposure."' US Depart ment ot Commerce. Nation* Bureau of Standards Hand book 69. issued June S. 1959. with Addendum I issued August 1963. Avadabie as NCRP Report No 22. The above documents, as wdl as information on nu merous other NCRP Reports addressing specific sub jects n onizmg radobon protection an available from: NCRP PuMcatons. 7910 Woodmont Ave.. Washington. DC 20014. LASERS to turnThe Wreshoid limit values are for expoaure tadiabon under conditions to which nearly Ml workers may be exposed without-adverse affects. The values should be used as guides in the control of exposures and should not be regarded as Ana lines between safe and dangerous levels. They are based on tne best avert able atformation from experimental studies. Limiting Apertures The TLVs expressed as radort exposure or kndience in this section may be averaged over an aperture ot 1 mm except tor TLVs for the eye in ths spectral range of 400*1400 nm. which should be averaged over a 7 mm (knifing aperture (pupil), and except for ail TLVs tor wa velengths between 0 1-1 mm where the fiminng aper ture a 10 mm. No modification of the TLVa a permitted tor puprt saes less than 7 mm. 65 The TLVs tor "extended sources" apply to sources which subtend an angle greater than a (Table 5) which vanes with exposure time. This angle a not the beam divergence of me source Correction factors A and 8 (CA and Ct) The TLVs for ocular exposure in Tables 3 and 4 are to be used as given lor alt wavelength ranges The TLVs tor wavelengths between 700 nm and 1049 nm are to be increased by a uniformly extrapolated (actor (Cj as shown in Figure 2 Between 1049 nm and 1400 nm. the TIV has been increased by a factor (C4) of five For certain exposure times at wavelengths between 550 nm end 700 nm. correction factor (C,) must be applied The TLVs for skin exposure art given m Table 6 The TLVs are to be eicreased by a factor (C,,) as shown in Figure 2 for wavelengths between 700 nm and 1400 nm To aid m the determination of TLVs tor exposure durations requiring calculations of fraction* powers Figures 3. 4. 5 and 6 may be used. Repetitively Pulsed Lasera Since there are few experiment* data for multiple pulses, caution must be used m the evaluation ot such exposures The protection standards lor irradiance or ra diant exposure ei multiple pulse trams have the following limitafions (t) The exposure from any single pulse m the tram is limited to the protection standard for a single compara ble pulse (2) The average irradiance for a group of pulses is tmited to me protection standard as given m Taoies 3. 4. or 6 ot a single pulse of the same duration as tne entire purse group (3) When the instantaneous Pulse Repetition Fre quency (PRF| of any pulses witnm a tram exceeds one. the protecoon siandard applicable to each pulse a re duced as shown m Figure 6 for pulse duratens less than 10~* second For pulses of greater duration, the follow ing formula should be followed 66 511904 0327 m tram /Standard! single puise\ Standard (pulse nr) n - numoer of pulses mtram r - duration ol a single pulse in the tram Standard (nr) * protection standard of one pulse having a duration equal to nr sec onds. 67 69 71 74 76 76 511904 0329 0<AnrU''NntftOi'*NNNN js J I 5 ilrl f*3fr 1 OI 79 S f a g i 1 i t g t ii 80 MCftOWAVCI These Threshold Limit Values refer to microwave en ergy m the frequency range of 300 MHz to 300 GHz and reoresent conditions under which is believed that near ly ad workers may be repeatedly exposed without ad verse effect Under conditions of moderate to severe heat stress, the recommended values mey need to Oe reduced * Therefore, these values should be used as guides m the control of exposure to microwave energy and should not be regarded as a hne Ire between sate and dangerous levels. Recommended V*km: The Threshold Limit Value for occupational exposure to microwave energy, where power density or field in tensity ts known and exposure time is controlled, is as follows: 1. For exposure to conteiuous wave (CW) sources, the power density level shall not exceed 10 mdlnrans per square centimeter (mW/cm*) for continuous expo sure. and the total exposure time shall be kmtied to an 8-hour workday This power density <s approxi mately equivalent to a free-space etoctnc field strength of 200 votts-per-meter rms (V/m) and a free-space magnetic field strength of O.Sampere-permeter rms (A/m). 2. Exposures to CW power density tareis greater than 10 mW/cm* are permttsftle up to a maximum of 25 mW/cm* based upon an average energy density of 1 mkliwaR-hour per square centimeter (mWh/cm1) averaged over any 0.1 hour period. For example, at 25 mW/cm*, the pemiesible exposure duration is approximately 2.4 mmules in any 6.1 hour period. 3. For repetitively pulsed microwave sources, the average held strength or power density is eakulaled by multiplying the peak-pulse value by the duty cycle. The duty cycle is equal to the pulse duration m sec onds times the pulse repetioon rate m Hertz. Expo sure during an 8-hour workday ah* not exceed the `Uumlore WW.XMlSUcuOMWn F IWQMl." PnaiWjl CEE.VOI S7. Me Z. Ftt IflM p 17V17I 81 following values which are averaged over any 0.1 hour period Power Oenuty Energy Density Mean Squared Electric Field Strength Mean Squared Magnetic Field Strength 10 mW/cm* 1 mWh/cm* 40.000 V*/m* 0.25 A*/m* 4. Exposure is not permissible CW or repetitively pulsed fields with an average power density in excess of 25 mWrcm' or approximate equivalent tree-space held strengths ot 300 V/m or 0.75 A/m. NOISE These threshold limit values refer to sound pressure levels and durations of exposure that represent condi tions under which it is believed that nearly all workers may be repeatedly exposed without adverse effect on their ability to hear and understand normal speech. The medical profession has defined hearing impairment as an average hearing threshold level m excess of 25 de cibels (ANSI-S3 6-1969) at 500. 1000. and 2000 Hz. and the lanits wtwen are given have been established to prevent a hearing loss n excess ot this level. The values should be used as guides m the control ot noise expo sure and. due to individual susceptibility, should not be regarded as fine hoes between sate and dangerous levels. ii should be recognized that the application of the TLV for noise will not protect ak workers from the ad verse effects of noise exposure A hearing conservation program witn audiometne testing is necessary when workers are exposed to noise at or above ihe TLV levels. Continuous or Intofmrteot The sound level she# be determmed by a sound level meier. conforming as a minimum to the requirements of the American National Standard Specification for Sound Level Meters. Si 4 (1971) Type S2A. and set to use the A-weignteo network with slow meter response. Duration ot exposure shall not exceed that shown m Table 7 These values apply to total duration ot exposure per working day regardless of whether this is one continu ous exposure or a number of short-term exposures but does not apply to impact or impulsive type ot noise When the daily noise exposure is composed of two or more periods of noise exposure of different levels. 82 ttwr combmed effect should be considered, rathe then the individual effect of each If the sum of the toNowmg tractions _Ci _C, T, T _C. T. exceeds unity, then, the mixed exposure should be con sidered to exceed the threshold lend value. Ci indicates the total duration of exposure at a specific noise level, and T indicates the total duration of exposure permitted at that level. AH on-the-pb noise exposures of 80 dBA or greater shall be used in the above calculations Table 7 Threshold Limit Values Ouraoon per day _____ Hours 16 8 4 2 1 1/2 1/4 1/8 Sound Level dflA* 80 85 90 95 100 105 110 115* a) Sound level in decibels as measured on a sound level meter, conforming is a mmtmum to the require ments of the American National Standard Specifica tion for Sound Level Meters. Si .4 (1971) Type S2A, and set to use the A-weighted narwork with slow meter response IMPULSIVE OS MlPACT NOME It is recommended that exposure to impulsfve or im pact noise shan not exceed the limits ksttd m Table 8 or taken from Figure 7 No exposures m excess of 140 de cibels peak sound pressure level are permitted. Impul sive or impact nooe s considered to be those variations m noise levels that involve maxima at euarvais of greater 83 than one per second Where the intervals are less Than one second, it should be considered continuous. Sound Level dB** 140 130 120 Tables Threshold Limit Values Impulsive or impact Noise Permitted Number ot Impulses or Impacts per 100 1000 10.000 **Dftn pwk sound prwtvn Wm 84 511904 0330 1 ' '111 " ................. mm utm <m mmmm at mkii tm im <> Rpw 7 --. Threshold Umi VaJue tor impulse/impact Mom. as ULTRAVIOLET RADIATION* These threshold hmii values refer to ultravtotoi radia tion m the spectr* region between 200 and 400 nm and represent conditions under which it is believed that near ly ail workers may be repeatedly exposed without ad verse effect. These values for exposure of the eye or the skm apply to ultraviolet radiation from arcs. gas. and vapor discharges, fluorescent, and incandescent sources, and solar radiation, but do not apply to ultravi olet lasers * These values do not apply to ultraviolet ra diation exposure of photosensitive individuals or of indi viduals concomitantly exposed to photosensitizing agents (Fitzpatrick, et ai. eds, Suniighi and Man. Umv Tokyo Press. Tokyo. Japan. 1974) These values should be used as guides m the control of exposure to continuous sources where the exposure duration shall not be less than 0.1 sec These values should be used as guides ei the control of exposure to ultraviolet sources and should not be re garded as a hne (me between sate and dangerous levels. flecom/neodetf Vetoes. The threshold twnit value lor occupational exposure to ultraviolet radiation incident upon skin or eye where irradiance values are known and exposure time is con trolled are as follows 1 For the near ultraviolet spectral region (320 to 400 nm) total irradiance incident upon the unprotected skin or eye should not exceed 1 mw/cm* tor periods greater man 10* seconds (approximately 16 minutes) and for exposure times less than 10* seconds should noi exceed one J/cm* 2 For the aclinic ultraviolet spectral region (200 -- 31S nm). radiant exposure incident upon the unprotected skin or eye should not exceed the valots given m Taole 9 within an 6-hour period 3 To determine the effective irradiance of a broadband source weighted against the peak of the spectral ef fectiveness curve (270 nm). me lollowmg weighting formula should be used. U - IE.S.AA *S LUW fiv* 86 where St/f Ei effective irradiance rotative to a monochromat ic source at 270 nm at W/cm*1(J2/s/cra2) spectral irradunco in W/cm*/nm S relative spectral effectiveness (umfless) Ax band width ki nanometers 4. Permissible exposure time in seconds lor exposure to actinic ultraviolet radiation modem upon the un protected skm or eye may be computed by diwdmg 0 003 J/cm* by E^r m W/cm* The exposure lane may also be determined using Table 10 wfuch pro vides exposure times corresponding to effective irradiances ei MW/cm*. TABLE 9 Relative Spectr* Effectiveness by Wavelength Wavelength (nm) 200 210 220 230 240 250 254 260 270 260 290 300 305 310 315 TLV fmJ/cm2)** 100 40 25 16 10 7.0 6.0 4.6 oo 3.4 4.7 ' 10 so 200 1000 RNibve Spectral Eftocbveness St 0.03 0.075 0.12 0.19 0.30 0.43 0.5 0.65 1.0 0.68 0.64 0.30 0.06 0.01S 0.003 . ee2f'- **l J/Ol** - 1ff-J/OV* 87 TABLE 10 Permissible Ultraviolet Exposures Ouration of Exposure Per Day Effective Irradiance. E^QiW/cm*)*'* 8 hrs ..................................................... 0.1 4 hrs....................................................... 02 2 hrs........................................................ 0.4 1 hr ....................................................... 0.8 30 min.................................................... 17 15 mm...................................................... 3.3 lOmm ................................................... 5 5 mm ..................................................... 10 1 mm........................................................ 50 30 sec .................................................... 100 10 sec...................................................... 300 1 sec....................................................... 3.000 0.5 sec....................................................... 6.000 0.1 sec..................................................... 30.000 All the preceding TLV's tor gttramotol energy apply to sources which subtend an angle less than 6<r. Sources which subtend a greater angle need to be measured only over an angle of 60*. i^wicm* - i0'*W/en** Rfn I -- Threshold lane Values for Ultraviolet Raduton Conditioned (tanned) individuals can tolerate stun ex posure m excess of the TLV without erythema! effects. However, such conditioning may not protect persons against skm cancer N0TCI OF MTENOC0 CHANGES (tor 1971) These physical agents, with tneu concspondmg val ves. comprise those tor which erthcr a kmit has bean proposed for the first time, or tor which a change m the "Adopted" listing has been proposed in both casts, the proposed limits should be considered trial limits that wiH remain m the hsbng for a period of at toast one year. If after one year no evidence comes to bght that questions the appropriateness of the values herein the values wdl be reconsidered for the ' Adopted'' kst. 69 NOTICE OF INTENT TO ESTABLISH THRESHOLD UNIT VALUES LIGHT AND NEAR-WFRARE0 RADIATION These Threshold Limit Values refer to visible and near-mtrared radiation m the wavelength range of 400 nm to 1400 nm and represent conditions under which it is believed that nearly alt workers may be exposed with out adverse effect These values should be used as guides m the control of exposure to light and should not be regarded as a fine line between safe and dangerous levels Recommended Vetoes. The Threshold Limit Value tor occupational exposure lo broad-band light and near-infrared radiation tor tha eye apply to exposure in any eight-hour workday and require knowledge of the spectral radiance (L) and total irradiance (E) of the source as measured at the postoon(t) of the eye ot the worker. Such detailed spectral data of a white lighi source is generally only required if the luminance of the source exceeds 1 cd cm'1. At lu minances toss than this value the TLV would not be ex ceeded. The TLVs are 1 To protect against retinal thermal injury, the spectral radiance ot the lamp weighted aganst the function R (Table 11) should not exceed. <400 * U.R. 4ii|/al (1)' where LnnW cm'* *' and \ is the viewing duration (or pulse duration if me lamp is pulsed) lim ited lo 1 ms lo 10 s. and o is me angular subtense of the source radians M the lamp is oblong, a refers to the longest dimension that can be viewed For in stance. at a viewing distance r 100 cm from a tubular lamp of length I - 50 cm. the viewing angle a *-l/r - 50/100 0.5 rad (2) 2 To protect against retinal photochemical injury from chrome biue-hgnt exposure the mttgrsed spectral ra- 90 511904 0331 dunce of the lamp weighted against the blue-fight hazard function B, (Table 111 should not exceed. ?U6.A)iS 100Jcm-sr-'(ta ID4*) (3a| T *L. B. ax 10-' Warr1 sr* (t > I0*s) (3b| For a source radiance L which exceeds 2 mW cm'* sr M m the blue spectral region, the permissible oposure duration u*, tn seconds is simply U, * 100 J cm-* sr'/L (blue) (4) The latter iimrts are greater than the maximum perrmssiOie exposure hmits for 440 nm laser radiation (see laser TlV) because a 2-3 mm pupil is assumed rather than a 7 mm pupil for the laser TlV. 3 Infrared Maton. To avoid possible delayed effects upon the lens of the eye (cataractogenesis). the infra red radiation (x > 770 nm) should be hmited to 10 mWcrrr*. For an infrared heat lamp or any near-in frared source where a strong visual stimulus n ab sent. the near infrared (770-1400 nm) radiance as viewed by the eye should be (meted to: L AX - 0.6/a (5)* for extended duration viewing conditions. This bmit a based upon a 7 mm pupd diameter. `fomtMM (l) and (21 tn amoral a* am not. ara* uwn, 0mwneotfy cermd f maw OK tecmiWi nnwiiwy coma, an* wu dm to naan a imuom qdmcic laoor uMipi lane mrnmiw wm tormuu Fe* tamwa <l) me Mwtd ka t, 1 rad $h/(cm* v). ter twmuu (S| I, - 1 w rM/ton* ar) AIRBORNE UPPER SONIC AN0 ULTRASONIC ACOUSTIC M0IATI0N These threshold limit values refer to sound pressure levels that represent conditions under which it is be lieved that nearly ail worlters may be repeatedly exposed without adverse effect. The values listed in Table IS should be used as guides m the control of noise expo sure and. due to individual susceptibility, should not be regarded as fine lines between safe and dangerous levels. The levels for the third octave bands centered below 20 kHz are below those which cause subiective effects Those levels for 1/3 octaves above 20 kHz are for prevention of possible hearing losses from subhar monics of these frequencies. TABLE 12 Permissible Ultrasound Exposure Levels Mid-Frequency of Third-Octave Band kHz One-Third Octave -- Band Level In dB reference 0 0002 dynes/cm1 10 12 5 16 20 25 31.5 40 SO 80 60 60 105 110 115 115 115 91 TABLE ft SPECTRAL WEIGHTING FUNCTIONS FOR ASSESSING RETINAL HAZARDS FROM 8R0A0 -- BAN0 OPTICAL SOURCES Wavelength (nm) Blue-Light Hazard Function B Bum Hazard Function Rk 400 405 410 415 420 42S 430 435 440 445 450 455 460 465 470 475 480 4B5 490 495 500-600 600-700 700-1049 1050-1400 0.10 0 20 0 40 080 090 095 0 98 10 1.0 0.97 094 0 90 0.80 0 70 062 0.55 0 45 0 40 0.22 0 <6 0 001 0 001 0 001 1.0 20 40 B0 9.0 95 9.S 10 10 97 94 9.0 80 7.0 6.2 55 45 40 22 16 10 10 t0.~-t.rmi 02 S3 PHYSICAL AGENTS UNDER STUDY These agents comprise those which the Physical Agents Committee of ACGIH proposes to study during this year to determine the feasibility of establishing pro posed TLVs in 1979. Comments and suggestions, ac companied by substantial evidence, are solicited, t. Mntnqumcy Maton. Specifically, that portion of the spectrum from 10 MHz to 100 MHz. 2. Extramety Low Frequency (ELF) Mabon. Specifical ly. that portion of the spectrum from 0 to 300 Hz. 3. Magnefte Fre/tfs. Both pulsed and continuous. 4. User Mmoon. Specifically ultraviolet radiation lor pulsed exposures, and repetitively pulsed light and infrared-A laser ex posures. 5. Wmomc Energy. Specificity. acoustic anargy * frequencies above 10 kHz. 6. Vibetfon. Segmental and whole body. 7. CoU Stress 6. Pressure Van*tons. 94