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FILE NAME State of the Art Literature SAL DATE 1960 Apr DOC SAL071 DOCUMENT DESCRIPTION Conference Presentation - Threshold Limit Values 4, - a Transactions of the | 5 TWENTY ANNUAL MEETING OF THE AMERICAN CONFERENCE OF GOVERNMENTAL INDUSTRIAL HYGIENISTS ROCHESTER NEW YORK _ April 23-26 1960 that this The Subcommittee consisting of L. Silverman 3. J. Pearce and H. Jordan has submitted a report on Recommendations Regarding Respiratory Protection Against Highly Toxic Aerosols This report has been circulated to the members and will be submitted for approval on April 25. The majority of the committee members believe report should be distributed to the ACGIH members This could be done by enclosing the page report in the newsletter to members or by publication in the AIHA Journal The committee has received three requests for technical information One request of interest was from A. E. Miller Chairman of the Subcommittes of on Breathing Air Standards the C.G.A. Medical Gases Committee At the chairman's suggestion Mr. Miller sent his request for information on air standards breathing to all of the committee members The committee will consider breathing air standards in its technical manual but has not had an opportunity to discuss such standards as a committes Two other requests ware from industry asking for information on specific contaminants The . by the Bureau of Mines chairman has U. S. answered such requests and recommended only devices approved . Distribution . Frank B. Adley Clyde M. Berry Ph.D. | Harry S. Jordan Jr. -.. S. J. Pearce Andrew D. Hosey Fred R. Ingran - Leslie Silverman Sc.D. William P. Tant Sc.D. Edwin C. Hyatt Chairman 7 The Report was accepted The final report on the agenda was that of the Committee on Threshold Limita which was presented by its Chairman Mr. Allan L. Coleman REPOROTF COMMITTEE ON THRESHOLD LIMIT VALUES following Your Committee on Threshold Limits Values suggests that the materials and values be placed on the tentative list for 1960 P.P.M. New Materials and Values to be Placed on 1960 Tentative List Approx.Mg . Cu.M. Acetonitrile POPES EOE TROT E SETH OCEEE EOS DECC EHO SH ERS BoronDOxiidce hlorodivinyl DDVP TOMO O Dimethyl MED eEOHODEH ESCO E OSD phosphate phosphate Katene COCR ere meee een eee re sere eee eeE eer eeseeneescess Nitropropane Prec escoeeessdereceoesevescesececcces Phosdrin CFPC ee ORT HEHE CODHOOO EHR EEE DEL EeEHe Systax SOOO OE C OO OEE EDAD OOD EME TOES Dene eesavevesce Trifluoroethane 1000 0.5 25 1000 24-08 24-08 24-08 0.9 24-08 0.1 0.2 7600 Also that the following be transferred from the tentative list to the list recommended values 77 Materials to be Suggested for Transfetro List of Recommended Valuss . Approx Mg + P.P.M. Per Cu.M.Air Boron Trifluoride POMOC eT OGeneneeoresreeeeToesE Chlorine Dioxide .. OO Oooo oerecreseooereesene 1 0.1 3 0.3 Dimethyl Formamide CPO COC HOH EerereorenerODnEeeS Dimethyl Hydrazine COC reer eseeeeererses 20 888 0.5 888 Glycolmethyl Ether 100 888 Furfuryl Alcohol POOCHTHSOH OEE DEEEECEHECEOOEES, 50 Lithium Hydride COCSOHOTEEAOCEHOSHREOOHOESCEOROS 200 0.025 . Phosphoric Acid COSCO OE DOS ET ERCEESLOOSELAOLE ES 1 Ittrium PPO COCO ODOC EO ROR SCREENER OEOOE EHH EES 5 It is further suggested that the value for chlorobromomethane be reduced from 400 p.p.m. to 200 p.p.m. in view of the high concentration of bromide found in the blood of animals after prolonged exposure to the higher concentration Cyclopropane should be removed from the list because of lack of published data to justify the previously listed 400 p.p.m. value it is suggested that the value for manganese be changed from 6 mg 5 milligrams per cubic meter of air . Also to Values decomposition past reports of 0.005 products p.p.m. are to replace being suggested for pentaborane and the less definite designations used . teflon in _ For the past years the mineral dusts have been listed in the table that these in alphabetical order This year your Committee proposes be listed under 3 major 3 miscellaneous classifications 1 silica 2 dusts silicates and | more foot A value of 5 million particles per cubic foot for dust containing than % crystabolite and a value of 20 million particles per cubic for amorphous silica have been added under the major heading silica . These changes are shown in the following table MINERAL AND METALLIC INCRGANIC DUSTS SUBSTANCE M.P.P.C.F. Silica Quartz High above 50 free silica POOCoarereacnceoe Medium 5 to 50 free silica Low below % free silica Crystabolite above % OOO emo coeeranereseeoseros Amorphous OC D EDE DEHOOETE OE Cedeceesneverececoer 50048 50048 5 0048 50048 50048 Silicates Asbestos CeCe ee HOOT sere reece nceercccccecccceena Mica eS ee i ' ee 2 Portland Cement OOM eer en erereseeseoessessseees Soapstone CROTCH HOMES EOC OLereceroreneeseneereenses Talc CORE OHHH TS HHOETETH ACE se Daeeoneseeeseresesee 48282 48282 48282 20 - 78 - Miscellaneous including Alundmum Oxide PITT YVITITITETTTTTTT TITTLE Calcite POHHSHHEHOHAEOEOHSOHHOESS EH OEDHEHHLOSESES Dolomite .sccccccscccccccccvecccsnssessceessees Limestone POOHEEOEEHOSOHOCHCEHEOHLES EE HHESHEHOEEEES Marble CROHOHSOROEEHEESEESO SCH HOREREHOTERTESEEESE Silicon Carbide PPTTTTTTTITITTTTT TTT M.P.P.C.F*. 222222 222222 222222 222222 222222 222222 Millions of particles per cubic foot of air based on impinger samples counted by field techniques ee . t JHMHPESHHH Your Committee has been greatly encouraged by the greater mumber of e reports received from industry and others in respect to observations relating to threshold limit values These were concerned with chloroacetaldehyde beryllium lithiumhydride sodium hydroxide and ammonia e exposures and some of them reported concentrations to which workers were exposed and correlated the extent and degree of exposure with the presence . or absence of injury or irritation Comments such as these based on the ~ observation of exposed workers are vital in the thorough documentation of threshold limit valus5 Considerable interes hats been shown through inquiries directed to your Committee in respect to exposures to oil mist in industry Some State units have suggested threshold limit values for oil mist without specific reference to the nature of the oil or to materials which it may . contain There also seems to be a variety of methods which have been investigated for determining atmospheric concentrations of these materials This problem is being studied by industry and governmental units and it is hoped that mufficient data will result from these investigations to enable your Committes to further study the matter of establishing threshold limits for these materials It is recommended that the Air Sampling Instruments Committee and The Recommended Analytical Methods Committee might also study and consider this problem It come to the attention of your Committee that threshold limit values are still being misused One of the apparent reasons for misuse appears to be the lack of universal understanding of the principles set forth in the foreward preceding the table of Threshold Limit Values One of the glaring examples of misuse relates to the use of Threshold Limit Values for comparing toxicity potentials of two or more materials Unfortunately very frequently one material is claimed to be so many times more toxic than another because the threshold limit value of one material has a correspondingly lower numerical threshold limit value It is recommended that all industrial hygienists become with the principles discussed in the foreword understand them and encourage and promote their proper use acquainted thoroughly Documentation of all the threshold limit values appearing on our list has been completed This should be publisdhureindg the coming year after final review and editing by your Committee - William L. Ball W. Clark Cooper Herbert Stokinger Keith H. Jacobson Hervey B. Elkins Warren Reinhart William Reindolla- Allan L.Coleman 22nd | 1960 ; ro . _ >>> 79 - : Threshold Limit Values for 1960 Adopted at the 22nd Annual Meeting of the American Conference of Governmental Industrial Hygienists Rochester New York April 23-26 1960 Threshold limits should be used as guides in the control of health hasards and should not be regarded as fine lines between safe and dangerous concentrations They represent conditions under which it is believed that hearly all workers may be repeatedly exposed day after day without adverse effect The values listed refer to time weighted average concentrations for a normal workday The amount by which these figures may be exceeded for short periods without injury to health depends upon a number of factors such as the nature of the contaminant whether very high concentrations even for short periods produce acute poisoning whether the effects are cumulative the frequency with which high concentrations occur and the duration of such periods All must be taken into consideration in arriving at a decision as to whether a hazardous situation exists Special consideration should be given to the application of these values in the evaluation of the health hazards which may be associated with exposure to combinations . of two or more substances Threshold limits are based on the best available information from industrial experience from experimental studies and when possible from a combination of the two These values are based on various criteria of toxic effects or on marked discomfort thus they should not be used as a common denominator of toxicity nor should they be considered as the sole criterion in proving or disproving diagnosis of suspected occupational . disease , . These limits are intended for use in the field of industrial hygiene and should be employed by persons trained in this field They are not intended for use or for modification for use in the evaluation or control of community air pollution or pollution muisances These values are reviewed annually by the Committee on Threshold Limits for changes revisions or additions as further information becomes available The Committee welcomes the suggestion of substances to be added to the list and also comments references or reports of experience with these materials RECOMMENDED VALUES \ ns { Substance Gases and Vapors P.P.M. Approx per Cu Mg . Acetaldehyde COO ee se nee eseHesseLEssoene 200 - 360 - Acetic acid COoeseeenceeeeeseeesensoese : Acetic anhydride Cecoesvevoseeeagaaesetootensea 25 20 Acetone COM OS ROSH H HOSE PO TEHRES EEO ODS - - 2,400 tetrabromide sescocercrecsese " Acrolein COO HCHEE CHEE HOEOE TEES OE DEEDE " Acrylonitrile COOKS EOC OREHEOE FED OOS ECLES 20 Allyl alcohol DOHC THESES HEHE TERE OE DERG S 45 - 80 Substance Gases and Vapors continued P.P.M. Approx Mg per Cu M. Allyl chloride ecovesascesccecccevese 5 2 ecssocsececes 15 ae 12 SS Allyl propyl disulfide disulfide Armonia secccecenccesccncecvccessece 100 70 e PO Amyl acetate coven accvcsecsoreenczce 200 1,050 A e Anyl alcohol isoamyl alcohol ..... 100 Ce Andline ccecccccscccsscvcesaseeaccns 5 360 ee 19 a 0.2 Arsine eccoccsnvecensevensvecucececs banzol YTTTITTCT TIT enr Benzene TTT Dean Bansyl chloride ceccacesccsvccsocore Boran trifluoride ccccccccsccesccers Bromine scscccacescecssessponsvesess 25 2 1 0.1 80 er 5 + 3 0.7 Butadiene 1,3 butadione 1, 000 2,200 250 740 Butyl acetate Butyl alcohol butyl acetate .... butanol peeeee ones 950 300 15 Butylamine ...... Butyl cellosolve butoxyethanol . ... Carbon dioxide eoenves Carbon disulfide ccosccccedteovecces 240 9,000 60 110 Carbon monoxide coseccescrescecconss Carbon tetrachloride cescsesecescces Cellosolve ethoxyethanol ....... Cellosolve acetate ethoxyethyl acetate 100 160 740 540 3 butadiene Chlorine cecscnccccevesesccescennves 0.1 0.3 Chlorine dioxide csccsessoocensecers 0.1 0.4 Chlorine trifluoride cccavosccevcece Chlorobenzene monochlorobenzene 350 Chloroform trichloromethane scecrs 50 240 20 100 nitropropane 0.1 0.7 Chloropicrin butadiene Chloroprene chloro ) 25 22 Cresol all isomers pecesecvasssese Cyclohexane PYYETTUTIT Tee 400 1,400 100 410 Cyclohexanol POY OTETEP IES eed 100 400 Cyclohexanone PTYPTTTIELIC I eee Cyclohexene wed veseeseossessssoeres 1,350 0.05 0.3 Decaborane methyl- Diacetone alcohol hydroxy pentanone ) PWEPTTYTT ILE ae Diborane ecvssecvececsssasveovsorsees 50 0.1 240 0.1 Dichlorobenzene essessesecosevenes 50 Dichlorodifluoromethane 1,0 00 4,950 Dichloroethane . Dichloroethane ethylena dichloride . Dichloroethylene evesceeesscnece Dichloroethyl ether coconesssoscecce Dichloromonofluoromethane nitroethano Dichlorotetrafluoroethane ....... . 100 200 15 1,000 10 1,000 wer: 81 Gases and Vapors continued - Substance P.P.M. Approx Mg per Cu M. Diethylamine POH CTS OOOO CODE reeuens Difluorodibromomethane Difluorodibromomethane Cewccvrecons Diisobutyl ketone SSOS CO dimethylaniline Dimethylaniline dimethylaniline Dimethyl formanide COSCO eLODeCceeS Dimethyl hydrazine Dimethylsulfate POCO C OCOD ESOL O SAEED Dipropylene glycol methyl ether .,. Dioxane diethylene dioxide Ethyl acetate COoowseceoeserensooes Ethyl acrylate Peo ethanol Ethyl alcohol ethanol eooeeccocnn Ethylamine COCR COR OEE ECO DRO CCCEDE Ethylbenzene COOP CRED EDO eee OevECE DS Ethyl bromide Poo eeeoscoreceooenone, Ethyl chloride Coeovesevcceoncusese Ethyl ether CORCC CO COOH OCHO EEO DO OEe Ethyl formate SOE OKeooHeeeoeevsEre Ethyl silicate CROCE CODE DECOESOEEDE Ethylene chlorohydrin Ethylenediamine COC OC OR OD SELOCEEDOS Ethylene dibromide dibromoathane Ethylene imine COvrerervosereeeseres Ethylene oxide COOTHHOOTOEEEOLCCE OS Fluorine ...... ...... ...... Fluorotrichloromethane cecevcovcers Formaldehyde OOanoreccerccsevveenes Furfural FOROTC OCC CERES DOES OE TOOLS Furfuryl alcohol COCO oaecrecrenes Hexane hexane Oeacoaecoseverese Hexanone methyl butyl ketone ..6. Hexone methyl isobutyl ketone Hydrazine .. CHO OREO EOE OEE OOSEED Hydrogen bromide sscccccccccvencecs Hydrogen chloride COCK Cede seeenEeEe Hydrogen cyanide scscccccccccoceces Hydrogen fluoride 90 CHE ........ OS . Hydrogen peroxide 90 ........ Hydrogen selenide Seoaeresosereanre Hydrogen sulfide Cwrccceoaceeeneoena Iodine CCC HOO rE Oe EEE OLEEEOOOSES Isophorone Beehesroaeoseresneeceone Isopropylamine CORKOHCE OO HEES OO DEEDS Mesityl oxida CHKORORLENLOLEL ORE DAS Mathyl acetate secaccovoncsccsecoes Methyl acetylene sescsssccccesceses Methyl acrylate CUS CLO MOH EBEsEE CE RS 25 100 50 5 20 0.5 1 100 100 400 25 1,000 25 200 200 1,000 400 100 100 . 5 10 ^>R 1,000 5 R83 R83 R83 - - - - 1.05 0.1 1,000 1,000 75 8888 8888 8888 an ov ee Onan Substance - 82Gases and Vapors continued vite. Approx Mg per Cu M. Methylal dimethoxymethane 1,000 3,100 ee 260 Methyl bromide methoxyethanol 21 80 Methyl cellosolve methoxyethanol 25 80 On Methyl cellosolve acetate ethylene glycol monomethyl ether acetate Methyl chloride trichloroethane Methyl chloroform trichloroethane 25 100 500 120 210 2,700 Methylcyclohexane CDeveveceseesecre Methylcyclohexanol Methylcyclohexanol OCC REHERE SE REDOfiS Methylcylobexanone Methylcylobexanone Methyl formate coccecccnnccceccceves 500 100 - - 2,000 470 460 250 Mathyl isobutyl carbinol methyl amyl alcohol Dee eerereseeeseososs -Nethyl styrene socccconcupeceece - Methylene chloride dichloromethane - Monomethyl * aniline cocscccucesevers - Naphtha coal tar - Naphtha petroleum seoecsconcoeroe - Nickel carbonyl cccccccsoccusccesee - Nitric acid scocccccesscnccceovoses - - Nitroaniline scescccvcccceovesnce - Nitrobenzene ecocevecccesecnececsers - Nitrosthana sececsccsvsssvcceccvece - Nitrogen dioxide sssccesvessccsscoce Nitroglycerin 0.5 Nitromethane seosecsccccscesscaceses - Nitropropane rere rrrerrrre tyr Nitrotoluene cecsccevsccsecseseenes - - Octane cocccevesessesseesessesessns Ozone coccccessscecsenseseeereseress Paradichlorobenzene ccocssvevecrers - - Pentane ketone Pentanone methyl propyl ketone 200 Perchlorethylene tetrachloroethylene 200 Phanol ... S Phenylhydrazine VUTEC Phosgene carbonyl chloride Phosphine TTT errr Phosphorus trichloride scccssccsese Propyl acetate ........ Propyl alcohol isopropyl alcohol Propyl ether isopropyl ether Propylene dichloride dichloropropane Propylene inine eccceccvasseereceve Propylene oxide -ccnnvcsvcsessoecce Pyridine eee eee ese ece esse sesso aeons Quinone ccscvessceseocscanesesssnes Stibine cececsecavecvsvsveseecesoce 5 1 0.05 0.5 200 400 500 75 25 100 10 0.1 0.1 Stoddard solvant ... 500 Styrene monomer phenylethylene 100 - 2,100 240 0.4 0.5 420 -83 -83 .- Gases and Vapors continued Substance | Sulfur dioxide hexafluoride Sulfur TTL TES hexafluoride Caen PP eecevens P.P.M. S Tetranitromethane Toluene ..... toluol Toluidine / PP diisocyanate diisocyanate T E / Tolylene diisocyanate TrieTrtihcyhllaormoientehylene Trifluoromonobromomethane OPO soccer evsesces Trifluoromonobromomethane Trifluoromonobromomethane / 200 25 Trifluoromonobromomethane ......... 1,000 xylol Xylene Xylidine Oo eer coro versceraces 200 Substance (HHH Toxic Dusts Fumes and Mists Aldrin hexa1hy,d2ro,1,4.538 ,4,10,11,4,4,5,8 0 dimethanonaphthalene dimethanoaphtalen ...... ANTU thiourea Arsenic OS soluble compounds ) CELLET Barium soluble compounds compounds ) Oo toe ere ecccccenes ee ae haat TTI ITT Te Tee Mg par M. 0.25 0.25 0.5 0.5 0.5 0.5 0.002 0.0 2 0.0 20.1 0.5 Chlorodiphenyl 0.5 42 chlorine 0.5 ~~, na - - 84 Substance Toxic Dusts Fumes and Mists continued we : Cu M. ++ Chromic acid and chromates as Cro Crag herbicide sodium 2-2,4 dichlorophenoxy dichlorophenoxy ethanol hydrogen sulfate dichlorophenoxy as Cyanide CN dichlorophenoxy dichlorophenoxyacetic dichlorophenoxyacetic dichlorophenoxyacetic dichlorophenoxyacetic DDT bis chlorophenyl Dieldrin 1,2,3,4,10,10 1,2,3,4,10,10 acid trichloroethane trichloroethane hexachloro trichloroethane 6,7,8,8a octahydro naphthalene DDiinniittrrootboelnuzeennee Cveeeroeracceneoses SPORES eCecoaceos fee ........ 0.1 15 S 10 " " - 0.25 Ferrovanadium dust PO OCCEOS EC DEO OOSEOC HELO CCE EOOS FHlyudorroiqudienone Iron Lead Lead OPC OOOO OPO ems ecccerreceereceneresoens OCHO OOOO ED ETCEEORee OE EORAOeDELeOe oxide fune COCO eRe eoosEereeeenoenEetereoosD dithiophosphate Lithium hydride COS COR CEC EDO DEdesEODEeeenoeeeees: Magnesium oxide fume OCOD dithiophosphate Malathion of disthyl mercaptosuccinate Bee disthyl Manganese OOOO OOO Oooo me crcescerereenonsecrosners organic compounds Mercury OOOO organic ee Marcury compounds Methoxychlor Methoxychlor trichloroethane trichloroethane mtricehlortoethhaneoxmypehetnyhl omxeythpohxye-pnheynly1,1,1l- fi/ fl fi fl fi fi/ fi/ fl fi fl fi fi/ fi/ fl fi fl fi fi/ 15 0.2 0.15 0.5 0.025 15 15 S 0.1 0.01 . 15 insoluble 0.5 nitrophenyl compounds ) ...... insoluble compounds PNaircaottihnieon..0.,.0.. 0,0 diethyl diethy msl 0.5 Phosphorus yellow Pe eee eee Se ee Phosphorus pentachloride CORO C CCR CEoesODEdECCECe . Phosphorus Picric acidpentasulfide Coe reeoereovenovrcessnecs COOH or er esreracaneeerereeeseeeneny Pyrethrum OOOO ROO Ream aseesewssencecessoceseves Rotenone as COMO Oe compounds Selenium as Se compounds COSCO eOR ECR OE LeeLee 1080 Sodium fluoroacetate Sodium Strychnine Strychnine ... hydroxide eeccescccceoveeereccecvctocess CCPC CORO ee ODDO OET TEE DECC ED Ee eaderes Sulfuric acid POCO OOO EE OEE OH HOT OONE OD EEeasens 0.50.50.5 0.1 0.1 0.1 0.1 0.150.1 0.1 0.15 0.15 0.15 d f ee ee a RS ae ee j eSLe i ~ or septal Ss a. od athe eS Le darhiblieieiemiebmdrenmast ht Lae TO Substance Taxic Dusts Fumes and Mists continued TEDP tatraethyl dithionopyrophosphate 0.2 TEPP tetraethyl Tellurium 2,4,6 Tetryl OCC pyrophosphate ........ Cee ere trinitrophenylmethylnitramine trinitrophenylmethylnitramine trinitrophenylmethylnitramine trinitrophenylmethylnitramine trinitrophenylmethylnitramine trinitrcoompphoeunndyslmethylnitramine Thallium soluble COCK O DOC O EEE ZESNS 0.05 0.1 1.5 tetramethyl 5 Thiram thiuram disulfide Trichloronaphthalens Titanium dioxide Trichloronaphthalens e re POAeO Ore rere eocceseesoseoes 15 15 5 1.5 soluble compounds insoluble Vanadium compounds OC oe eo eerecvensoaceres WarfaVVr220i0nV20 dfuumseftacetonylbenzyl hydroxycoumarin Yttrium 3- COP CPOE EE ODe HR ) DEeeEEDOOOEEC hydroxycoumarin SOOO facetonylbenzyl facetonylbenzyl facetonylbenzyl facetonylbenzyl RE BEDS ORE SED OBER S COFCO ROCHE OOOO ORES ED OOH EOE T EOC EEEEOOOS Zinc oxide fume SP as as Zr Zirconium compounds Po eCe EET Esooresocere 0.05 0.25 0.5 0.5 0.1 0.5 15 15 5 24 Radioactivity For permissible concentrations of radioisotopes in air see U. S. Department of Commerce National Bureau of Standards Handbo 69 Maximum Permissible Body Burdens and Maximum Permissible Concentration of Radionuclides in Air and in Water for Occupational Exposure June 5 19 Also see U. S. Department of Commerce National Bureau of Standards Handbook 59 Permissible Dose from External Sources of September 1954 and addendum of April 15 1958 Ionizing Radiation ++ Milligrams of dust fume or mist per cubic meter of air Mineral and Metallic Inorganic Dusts Substance - oa M.P.P.C.F ** Silica Quartz Se High above 50 free silica .. 887 Medium 5 to 50 free silica 88 7 Crystabolite above % ...... ...... Amorphous oesccrecccceccsscesnvacscconvecec..., Silicates cenecereacssccenenecvcceccce Asbestos oOo e seem er Portland Mica COCO Hereeeeseeoore OC COCC DR CeereHessveces Cement COCR e eee reencccreceneesecceceue Soapstone OOo eter eee remeber oreenocesecoeeeees Talc woscveccveccccccnsssccceseccecscecceccecs, 5 20 >>">> - 86 Mineral and Metallic Inorganic Dusts continued M.P.P.C.**F* Aluminum Oxido COC e EDOM EEE DES eed OC EO OOF OEE Calcite OOOOH OE HOC OHO H OH ETO SEES EOE DERE CE EEEE Dolomite COS OOOH REO EEESE ET EOOEEVEE REO OEE OED Limestone CASO HOOEHOCH EEE KE OROO EE VERE DEORE EOS Marble COC COCO OF OE SHEE ODE OOOO DEES DEER CeS Silicon Carbide COCOOCE HOHE CHEE E EE EOL OR OREOES 50 50 50 50 50 50 of ibllions particles per cubic foot of air based on impinger samples counted by field techniques Substance TENTATIVE VALUES Acetonitrile Cone ether AGE P.P.M. 22 Approx Mg per Cu ## ornemm Boron oxide .... OO DORE OTE CESSES ESECHES ornemm > ( -) Butyl mercaptan Pe oeresecersceccerecs 2248 ornemm . Chloroacetaldehyde 2248 or nemm Chlorobromomethane Chlorobromomethane COCR O SEO OLE Dichlorodivinyl RESDS DDVP Dimethyl Dichlorodivinyl phosphate COHCORO COOH RED ECREOONEEDS 2248 Diglycidyl ether ..... 20 1,050 l 55 Ethyl mercaptan ceccccccuccccsesveces Glycidol OOOH CHRO TC HOOTORSEELEOSOOOEDE 20 50 640 150 Hexyl acetate ssccccccccsccsccece 100 ; 590 Ketens CoC COC eee OEEEHE ROSE ODOCES 0.5 0.9 Methyl mercaptan secescscccccccccvers 50 Nitropropane 100 F COO ORO DOC OC OEE ERE O SCS 25 0.005 Pentaborane 90 90 COCO HOHE D ERE COED ESSEC 0.01 Perchloromethyl mercaptan ............ 0.1 0.8 -\ Phosdrin COS SHHEREEHOR ETE SH EOCELOVEDS Propyl nitrate 25 Systox POOR CHT oC DE CLO EeCCEnEORS Teflon decomposition products ...... 0.005 Trichloropropane 50 Triorthocresyl phosphate Ceovccrsesece * Parts of vapor or gas per million parts of air by volume ## Approximate milligrams per cubic meter of air 0.1 110 0.2 3 00 0.1