Document kDqerRNoJaQgr8rOKrwne5Zyy

NORTH CAROLINA STATE BOARD OF HEALTH* J. W. R. Norton, M, D., State Health Director Raleigh THRESHOLD LIMIT VALUES FOR 1963 CONSULT LOCAL HEALTH DEPARTMENTS AND PHYSICIANS CONTROL HEALTH HAZARDS TO EMPLOYEES AT WORK PREVENT INDUSTRIAL DISEASES `Made Available by The Occupational Health Section (SEE INSIDE COVER) '' ` / - -- 'V' ADVISORY GUIDE SERIES i - 1963 Revision (Replaces Issue of September 1962) SEPTEMBER 1963 OLI 3738 PUBLISHED IN CONFORMITY WITH GENERAL STATUTES OF NORTH CAROLINA (130-11) * REPRINTED WITH PERMISSION FROM THE AMERICAN CONFERENCE OF GOVERNMENTAL INDUSTRIAL HYGIENISTS PERMISSION GIVEN TO REPRODUCE THIS MATERIAL, COPYRIGHT 1963, BY LETTER DATED AUGUST 27, 1963 OLI 3739 THRESHOLD LIMIT VALUES FOR 1963 Adopted at the 25th Annual Meeting of the American Conference of Governmental Industrial Hygienists Cincinnati, Chio May 6,7, 1963 Threshold limits should be used as guides in the control of health hazards and should not be regarded as fine lines between safe and dangerous concentrations. They represent conditions under which it is believed that nearly 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 v/ithout 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. Because it has been recognized that the threshold limits of certain acutely-acting substances may not provide a safety fac tor comparable to that of chronically-acting substances for which a time-weighted average applies, a "C" designation or "ceiling" has been affixed to such values in dicating that the Threshold Limit Value should not be exceeded. The bases for the "C" listing is given in appendix C. Special consideration should be given to the application of these values in assessing the health hazards which may be associated with exposure to combinations of two or more substances. A brief discussion of basic considerations involved in developing threshold limit values for mixtures, and methods for their development, amplified by specific examples are given in appendix E. 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 dis comfort; 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 interpreted and employed only by persons trained in this field. They are not in tended for use, or for modification for use, (1) as a relative index of'toxicity, by making a ratio of two limits, or (2) in the evaluation of control of 'community air pollution or air pollution nuisances, or (3) in estimating the toxic potential of continuous uninterrupted exposures. These values are reviewed annually by the Committee on Threshold Limits for 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. ^"Documentation of Threshold Limit Values" is a compilation by the Committee on Threshold Limit Values of the best available technical evidence substantiating these VALUES. It can be purchased from the Secretary-Treasurer, American Conference of Governmental Industrial Hygienists, 1014 Broadway, Cincinnati 2, Ohio, price $4. OLI 3740 -1- Substance BECOHUENBED VALUES (in Alphabetical Order) Acetic acid---------------------------------------------------------------------- Acetic anhydride----------- --------------------- ---------- ------- Acetone------------ ----------------------------------------------------------------- Ac etonitrile-----.........------------------------------------------------- Acetylene tetrabromide------------------------------------------------- tAcrolein--------------------------- ----------------------------------------------- Acrylonitrile - Skin---------------------------------------------------- Aldrin (l,2,3410,1O-hexachloro-1,4,4a,58,Sa-hexa- hydro-1,4,5, S-dimethano-naphthslene) - Skin---- fAllyl alcohol - Skin-----------------^------------------------------------- Allyl chloride------------- ------------------------------------------ Aliyl glycidyl ether (AGE)-------------------------- --------- Allyl propyl disulfide-------------------- --------------- --------tAmmonia------------------------------------------------------------------------ Ammonium sulfamate (Ammate)---------------------------tAnyl acetate------------------------ --_____ _ ______ --________ Amyl alcohol (isoamyl alcohol)---------- - ....----- Aniline - Skin----------- - -------,------------------------------------------ Antimony---------- --------------------------------------------------------------- ANTU (alpha naphthyl thiourea)------ ------------------------------Arsenic--------------------------- ,----------------------- ------------ Arsine---------------------------- ------------------------ ------------ Barium (soluble compounds)----------- -------------- ----- Benzene (benzol) - Skin ---- ----------- -------------- ------- Benzidine-- -- -- ------------------------------------- Benzyl chloride------------- -- -. -------- ------ Beryllium----i---------------- ----------------------------------------------- Boron oxide--------------------------- --------------------------------------- Boron trifluoride-------------------------------------------------------- Bromine- ,-- . ...-- -------------------------------------------------- Butadiene (1,3-butadiene)----------------- ------------ -------- 2-Butanone (methyl ethyl ketone)---------- ------ -------------- 2-Butoxy ethanol (Butyl Cellosolve)--.----------------------- Butyl acetate (n-butyl acetate)----------------------------------- Butyl alcohol------------ ------------------- ----------------------- tert. Butyl Alcohol----------------------------------------------------- Butylamine------------ - , ------------ ------------- ------------ n-Butyl glycidyl ether (BGE)----------- ------------------------ Butyl mercaptan------ ---- -------------------- -- p-tert. Butyltolueno----- - ------------------ ------- Cadmium oxide fume------------------- -- ----- ------ ---------------------- Calcium arsenate------- -- -------- ---- --------------------- - ppm* 200 10 5 ,000 40 1 0.1 20 2 1 10 2 50 -- 100 100 5 -- -- -- C.05 -- 25 1 -- -- 1 0.1 ,000 200 50 200 100 100 5 50 10 10 -- w Vg/W 360 25 20 2,400 70 14 0.25 . 45 0.25 5 3 45 12 35 15 , 525 360 19 0.5 0.3 0.5 0.2 0.5 80. A1 5 0.0C2 15 3 0.7 2,200 590 240 950 300 300 15 270 35 60 0.1 1 T1963 Revision Note: The word ''skin1' following a substance indicates that the substance can pene trate the skin to contribute to- the exposure and threshold limit value should be reduced accordingly. A Numbers, See Appendix A OLI 3741 -2- Substance ppm* Carbon dioxide........ Carbon disulfide - Skin- Carbon monoxide---- Carbon tetracholride -- Skin- Chlordane (l,2,4,5,6,7,8,8-octachloro-3ay4,7,7a-tetra- hydro-4,7-methanoindene)-------- ................... .................... Chlorinated camphene, 60%------------------ ------------------------- Chlorinated diphenyl oxide------ - ------------- Chlorine---------------------------------------------------------------------- ------ Chlorine dioxide------------------------------------------------------- Chlorine trifluoride-------------------------------------------------------- Chloroacetaldehyde- Chlorobenzene (monochlorobenzene)* Chlorobroraomethane------------- -- Chlorodiphenyl (42% Chlorine) - Skin- Chlorodiphenyl (54$ Chlorine) - Skin- Chloroform (trichloromethane)------------- 1-Chloro-l-nitropropane----------------------- Chloropicrin-- Chloroprene (2-chloro-l, 3-butadiene)- Chromic acid and chromates (as CrO,)* Cobalt------------------------------------------------- hydrogen sulfatej- Cresol (all isomers) - SkinCyanide (as CN) - Skin--------CyclohexaneCyclohexanol---- Cyclohexanone---- Cyclohexene- 2,4-D (2.4-dichlorophenoxy-acetic acid)-----------------------DDT (2,2-bis (p-chlorophenyl)-l,l,l-trichloro- ethane) - Skin----------------------------------------- ---- Decaborane - Skin--------------------------- ------ ------*-------------- -- Diacetone alcohol (4-hydroxy-4-methyl-2-pentanone)--- Didorane-------------------- ----------------- ------------- - -----------------1,2-Dibromoethane (Ethylene dibromide)o-Dichlorobenzene---------- ------------- --------------p-Dichlorobenzene------- -- ------------- ---------- Dichlorodifluoromethane------ -------------------1.1- Dichloroethane------------------------------------1.2- Dichloroethane (ethylene dichloride)* 1.2- Dichloroethylene------------- ------------------Dichloroethyl etherDichloromonofluoromethane-- 1,1-Dichloro-l-nitroethaneDichlorotetrafluoroethaneDieldrin (1,2,3,4,10,10-hexachloro-6,7-epoxy-l, 4,4a, 5,6,7,8, Sa-octahydro-1,4,5,8-dimethanonaphthalene) - Skin-------------- DiethylamineDifluorodibromomethanefDiglycidyl ether (DGE)- Diisobutyl ketoneDimethyl acetamide - Skin- 5,0C0 20 100 10 ___ ,,rr 1 0.1 0.1 1 75 200 -- 50 20 0.1 25 ol ___ _ 5 400 50 50 400 -- -- 0.05 50 0.1 25 50 75 1,000 100 50 200 . 15 1,000 10 1,000 25 100 0.5 50 10 9,000 60 no 65 0.5 0.5 0.5 3 0.3 0.4 3 350 1,050 1 0.5 240 100 0.7 90 0.1 0.5 15 22 5 1,400 200 200 1,350 10 1 0.3 2400.1 190 300 450 4,950 400 200 790 90 4,200 60 7,000 0.25 75 860 2.8 290 35 OLI 3742 -3- Substance Dimethylaniline (N-dimethylaniline) - Skin------ --------- 1,l-Dimethylhydrazine - Skin---------------------------- ---;-- Dimethylsulfate - Skin--------.-------- --------------------------- ---- Dinitrobenzene - Skin" -- - - - a- Dinitrotoluene - Skin------------------------------------------------------ - Dinitro-o-cresol - Skin--------------------------------------------------- Dioxane (diethylene dioxide)------------------------- ------------- Dipropylene glycol methyl ether-------------------------------------- EPN (O-ethyl O-p-nitrophenyl thionobenzenephosphonate) -Skin------------------------------------------------- Ethyl acetate____ ______ _______________________________ --. Ethyl acrylate - Skin------------------------- ---- -......... Ethyl alcohol (ethanol)------------ ~ Ethylanine---------------------- _------------------------------ --------------i~ Ethylbenzene------------------------------------- --- ------------ ------ -- Ethyl bromide-------------------------------- - -- Ethyl chloride------------------------------------------------------------- Ethyl ether----------- ------- -------------------------------------- ------ ------ Ethyl formate----------------------------------- --------- `Ethyl mercaptan--------------------------------------------- Ethyl silicate----. ---- ------- Ethylene chlorohydrin - Skin-----------------------Ethylenediamine--------------------------------------- .--;-- -- Ethylene glycol dinitrate (Combined EGDN + NG) - SkinEthylene ixnine - Skin------ --.... ----------- ---------------- Ethylene oxide----........ -------------------- --.--i------- 2-Ethoxyethancl (Cellosolve)-------- -- ........--- 2-Ethoxyethylacetate (Cellosolve Acetate)-- -- r r ..-- Ferbam (ferric dimethyl dithloearbamate)-- Ferrovanadium dust - -- v ------ Fluoride (as F)------------- -I.'......----. Fluorine-- ------ -- -------------- - - -i --. Fluorotrichloromethane------ ' .-- Formaldehyde----i--.------- --.. -- Furfural----------------------- ---- Furfuryl alcohol---- --------- ------ ----- Gasoline------ -- ------ ----------------- ------- -------- ------ Glycidol (2,3-Epoxy-l-propanol)-- .................................. Heptane (n-heptane)-------- ------------- ------- --- Hexane (n-hexane) ................. ....------------------ Hexanone (methyl butyl ketone)------------------ -------- ---- -j.sec-Hexyl acetate ----- - -------------- Hexone (methyl isobutyl ketone)------------------- --------------- Hydrazine - Skin..... ----- -- . ---------- ------------ Hydrogen bromide- --------------- ,--------------------- ------ ---------- Hydrogen chloride " ----------- Hydrogen cyanide - Skin---------------- --------------- -------- Hydrogen fluoride---- -------------------- ------ ---------------------- Hydrogen peroxide, 90%---------------............... Hydrogen selenide---------------------------------------------- Hydrogen sulfide--..------ - --' -- -- Hydroqulnone-----------......... ..... -------- ^-------------------- -- ppm* 5 20 0.5 1 --- 100 100 400 25 ,000 25 200 200 .,000 400 ICO 20 100 5 10 0.2 5 50 200 100 __ ' --- -- ' o.l 1,000 5 5 50 500 50 500 500 100 50 100 1 3 5 10 3 1 0.05 20 -- 25 60 1 5 1 1. 0. 360 600 0. 1,400 100 1,900 45 870 890 2,600 1,200 300 52 j j -' 850 16 30 1. 9 90 740 540 15 1 2. 0. 5,600 6 20 200 2,000 150 2,000 1,800 410 295 410 1. Xf +1VV* 0O 10 7 n 2 i, 0, 30 2 |1963 Revision OLI 3743 -4- Substance Iod ine------~------------- -____.________________ --________ ____ Iron oxide fume-- Isophorone------------ ,--_____ _______ -- -...---......... -- Isopropylamine--- --. ....... .......... .............. - .----- Isopropyl glycidyl ether (IGE)-------- --------- ------------- Ketene--...... ...... ......-- ___________ -- Lead-------------------------- ------ ----------------- ----------- -- Lead arsenate---------------------------------------------------------- .--- Lindane (hexachlorocyclohexane, gamma isomer)-.........-- Lithium hydride-------------------------- ---------------------- . Magnesium oxide fume----------------- ---------- ---->. -- Malathion (o,o-dimethyl dithiophosphate of diethyl mercaptosuccinate) - Skin-------------------------- ----- Margane se---------------------------------------------------- -------- --------- - liercury - Skin------------------------------ --------- ---- Mercury (organic compounds) - Skin ------ Jfesityl oxide----- ------------------------------------------ ------ ffethoxychlor (2,2-di-p-methoxyphenyl-l,1,1-trichloro- ethane )----------------------- --------------------------- ------ Methyl acetate-------- *-------------------------;-- ------- - Ifethyl acetylene------------------------- -------------- ------------- -- Methyl acrylate - Skin------------------ .----------------------- Methylal (dimethoxymethane )--------------- --------------------- ---- Methyl alcohol (methanol)-------.----------------- -- Methyl bromide - Skin-------------------------------- Methyl cellosolve (2-methoxyethanol)' - Skin -- --- Methyl cellosolve acetate (ethylene glycol monomethyl ether acetate)- -- Methyl chloride---------------------~............... - ---- Mfethyl chloroform (1,1,1-trichloroethane ) . ------- Methylcyclohexane-- --------- ----- ------------------ Methylcyclohexanol----------- ---------------------------- ------- Methylcycldhexanone-------------- ---------- .................... -- Methyl formate-------- ---------------------------- Methyl isobutyl carbinol (methyl amyl alcohol)----------- +Methyl mercaptan--------- ------------------------------- -------- `a Methyl styrene... .----- -- ------ ----------- Methylene chloride (dichloromethane) -- . - Monomethyl aniline - Skin-- ----.............. ......... --- Molybdenum (soluble compounds)--------- --- -- ------ (insoluble confounds)------------ - --. Naphtha (coal tar)-------------- -------------------Naphtha (petroleum)-----*4--------- -- -- ----- B-Naphthylamlne---- --------....---------------- ------ Nickel carbonyl- --------- --------------- Nicotine - Skin-------- ---------------------- ------ Nitric acid------------------------- --:---------------------- p-Nitroaniline - Skin---------- ~ Nitrobenzene - Skin-------- - ' Nitroethane---- ------- ---------- Nitrogen dioxide------------ ---------- ------------- ' " -- Nitroglycerin (combined EGDN + NG) - Skin------~ Nitromethane-------------------------------------- --- ------------------------ ppm* 0.1 ,,ii- . 25 5 50 0.5 -- ,----------- ,-T -- _---------- 25 ___ 200 1,000 10 1,000 200 20 25 25 100 350 500 100 100 100 25 20 100 500 2 _____ 200 500 0.001 10 1 1 100 5 0.2 100 1 15 140 12 240 0.9 0.2 0.15 0.5 0.025 15 15 C 0.1 0.01 100 15 610 1,650 35 3,100 260 80 80 120 10 1,900 2,000 470 460 250 100 40 480 1,750 9 / 15 800 2,000 Az 0.007 0.5 25 6 5 310 9 2 250 ^1963 Revision OLX 3744 -5- Substance l~Nitroprbpane-------------- - ---------------------------------------- 2-Nitropropane--. -- --------------------------------------- Ib-llitrosodimethylamine (Dimethylriitrosainine) - Skin- Kitrotoluene - Skin--------:------.......-------- ------------ Octane-------------------------------------------- :--------------------------------- Osmium ietroxide-------- ------------------------------------------- Farathion (0,0,diethyl-O-p-nitrophenyi thiophos- phate) - Skin----------- ---------------- -- Pentaborane------------------------------------------ ----- ---------- pentachloronaphthalene - Skin--*-------- Pentachlorophenol - Skin------------------------- Fentanone (methyl propyl ketone)---- Pentane-------- ----------------------------------------- Perchloroethylene (tetrachloroethylene) Perchloromethyl mercaptan-- --------- Perchloryl fluoride---------------- ------------- -- Phenol - Skin------ ------ -------- -------------------------------------- Phenyl glyciayl ether (PGE)------------------------------------ Fhenylhydrazine - Skin--------------------------------------------- Phosdrin (2-carbomethoxy-l-nethyl vinyl dimethyl phosphate)---------- .......---------------- Phosgene (carbonyl chloride)------------------------- ------- f Fnosphine------------------ -------- ---- ------------------- ---- Phosphoric acid--------------------- ---........----- - ----- Phosphorus (yellow)---------- -. ... .... -- Phosphorus pentachloride------- --------- Phosphorus pentasulfide------------ ------ -------- Phosphorus trichloride------ -------------------- Picric acid - Skin-------------- ---------- -- - Platinum (Soluble Salts)------- ---- ---------- --- Propyl acetate ............. ........:----------------- -- Propyl alcohol (isopropyl alcohol)----------- ---- Propyl ether (isopropyl ether)-------------------------- -- n-Propyl nitrate------------------------------------- -------------- Propylene dichloride (1,2-dichloropropane)---- Propylene inline - Skin----- ------------- Propylene oxide-------------------------------------------------------- Pyrethrum------------------ ---------------- ------------ pyridine-------------------- --------- -- ---- . ------ Quinone-- . ' ' ------ -------- ------ Rotenone (commercial)---................. ............... Selenium compounds (as Se)------- -------------- Sodium fluoroacetate (1080) - Skin---------- Sodium hydroxide---- - - - ------ ------------ ----------- Stibine--------------------- :-------------------------- Stoddard solvent-- ------------ ----------------- Strychnine-------------------------- ----------- Styrene monomer (phenylethylene)----- Sulfur dioxide-------------- Sulfur hexafluoride---------------------- Sulfuric acid-------------------------------- Sulfur monochloride------- .. ------------ Sulfur pentafluoride---- 1963 Revision --6-- ppm* 25 25 A3 5 500 -- 0.1 -- 0.005 -- -- 200 ,000 100 0.1 3 5 50 5 1 0.3 0.5 200 400 500 25 75 25 100 5 0.1 0.1 500 100 5 1,000 1 0,025 ife/M3** 90 90 -- 30 2,350 0.002 0.2 0.1 0.01 0.5 0.5 700 2,950 670 0.8 13.5 19 310 22 0.1 4 0.4 f /LAaaJ-4 1 ** N s 0.1 v.v 1 1 3 0.1 0.002 840 980 2,100 110 350 60 240 5 15 0.4 5 0.1 0.05 2 0.5 2,900 0.15 420 13 6,000 1 6 0.25 OLI 3745 Substance Sulfuryl fluoride-------- ---------------------------------- ------------- 2,4,5T (2,4,5-Trichlorophenoxyacetic acid)------ TEDP (tetraethyl dethionopyrophosphate) - Skin----- Teflon (R) decomposition products---------------- --------- TEPP (tetraethyl pyrophosphate) - Skin------------------- Tellurium------------ ------------------------------------------- -------- 1.1.2.2-Tetrachloroethane - Skin-- -................... Tetrahydrofuran------------------ ------------ . . .......- Tetranitromethane-------- ------------------------------------- -------- Tetryl (2,4,6-trinitrophenylmethylnitramine) - Skin- Thallium (soluble compounds) - Skin--------------------- Thiram (tetramethyl thiuram disulfide)------------------ Titanium dioxide-------------------------------- --------------------- Toluene (toluol)------------------------- - --...-- -- -- -- o-Toluidine - Skin----------- ,, , -------- Tolylene-2,4-diisocyanate---------------------------------------- ----- Trichloroethylene------------------------- -------------------- ----- Trichloronaphthalene - Skin----- -- --- ---- -- 1,2,3-Trichloropropane------ ---------------------- -- -------- ---- 1.1.2-Trichloro 1,2,2-trifluoroethane------------- ---- Triethylamine-- ---------- ------------------------------ ------ ----- Trifluoromonobromomethane--------------------------------- ------ ---- Trinitrotoluene - Skin--------- ------------- ---------------- Triorthocresyl phosphate----------- ----------------------------------- Triphenyl phosphate------- --------------- --------------- Turpentine--- - ------------- -- .......-- -- ----- Uranium (soluble compounds)--------------- --, -- .---- (insoluble compounds)----------------- ----------- Vanadium C(V-Oe dust)----------- --------- ------ (V^ fume)----------------------------------------------------- Vinyl chloride (chloroethylene)---------------- --------- -- Vinyl toulene------------- ----------------------- -- --------------Warfarin(3 (a acetonylbenzyl) -4-hydroxycoumarin)-- Yttrium -- -- -- ............................. -- -- -- ---- Xylene (xylol)----------- ---- Xylidene - Skin----------------------- ---------------- > -- Zinc oxide fume-------- ------- -------------------- --------Zirconium compounds (as Zr)----------------- ------------- -------- ppm* 5 200 5 0.02 100 50 1,000 25 1,000 100 500 100 200 5 20 10 0.05 0.1 35 590 8 1.5 0.1 5 15 750 22 0.14 520 5 300 7,600 100 6,100 1.5 0.1 3 560 0.05 0.25 0.5 0.1 1,300 480 0.1 5 870 25 5 5 Radioactivity: For permissible concentrations of radio-isotopes in air, see U.S, Department of Commerce, National Bureau of Standards, Handbook 69, "Maximum Per missible Body Burdens and Maximum Permissible Concentrations of Radionuclides in Air and in Water for Occupational Exposure," June 5, 1959. Also, see U* S. Depart ment of Commerce, National Bureau of Standards, Handbook 59, "Permissible Dose from External Sources of Ionizing Radiation," September 24, 1954, and addendum of April 15, 1958. Note: The word "Skin" following a substance indicates that the substance can pene trate the skin to contribute to the exposure and threshold limit value should be reduced accordingly. Parts of vapor or gas per million parts of air by volume at 25C and 760 mm. Hg pressure. "Approximate milligrams of particulate per cubic meter of air. A Numbers, See Appendix A OLI 3746 -7- MINERAL dusts Substance SILICA Crystalline Quartz, Threshold Limit calculated from the formula----- Cristobelite " " Amorphous,includingnaturaldiatomaceousearth-------- SILICATES (less than 1% crystalline silica) Asbestos------------------------- -------- --,,----- ------ ....... -I----------------Mica------------- ---------- ------_______________------ ------- -- Soapstone----------------------------------------- --------------------------- Talc----------------------------------------------------------------------------------------Portland Cement------------------------------------- ------ .... ------------ Miscellaneous (less than 15?crystallingsilica)-- Conversion factors: ---------------- mppcf x 35.3 = million particles per cubic meter - particles per c.c. m,p.p.c.f. 250 %S10s + 5 20 -5 20 20 20 50 50 g Millions of particles per cubic foot of air, based on impinger samples counted by light-field technics. = The percentage of crystalline silica in the formula is the amount determined from air-borne samples, except in those instances in which other methods have been shown to be applicable.** **SEE TENTATIVE VALUES ON FOLLOWING PAGE. OLI 3747 TENTATIVE VALUES Substance tert. butyl chromate (as CrO^) - Skin----------- "Calcium oxide ------------- ------------------------ Camphor---------- -------- ------------------.-------------------- "Copper Fume............................ ............................................... Dusts & Mists-------- -------------. -- ------- .....----- DDVP (0,0-Dimethyl-2,2-dichlorovinyl phosphate)----- "Demeton (R) (Systox)--------------------------------... - ...----- -- Endrin (1,2,3,4,10,10-hexachloro-6,7-epoxy-l,4,4a, 5,6,7,8,8a-octa hydro l,4-endo-5,8-dimethano- naphthalene) - Skin-------------- ---------- -- -------- Epichlorhydrin---------------- ------------------------------------------- Ethanolamine----........... ......................... ........................ -- "Graphite-------------------- ----.............. .................... -- "Hafnium------------------------------------------------- --------------------- Heptachlor (1,4,5,6,7,8,8a-heptachloro-3a,4,7,7a- tetrahydro-4,7-methanoindene)-------- ------ --- ------ "Methyl amine----------------------------------- ----------- ------------ ---- "Methyl Methacrylate----------------------------------------------------- "Methylene bis phenylisocyanate------ -------------------------- "Mineral Wool (Fiberglas)------------------------ --- --- "Naphthalene------------------------------ ------------------------- Oil (mineral)-------- ------------- ----------- ------------------------- "B-Fropiolactone-----------------------------...----------------- ---- "Silver--------------------------------------------------------------------------- "Tantalum------------------------------------- ----------------- -------- "1,1,1,2,-Tetrachloro-2,2-difluoroethane ---------- "1,1,2, 2-Tetrachlore-l, 2-difluoroethane -- "Tetraethyl lead - Skin------------------- --...--------- "Tin (inorganic compounds)------------- ----------------- ------- .-- (organic compounds as Sn) - Skin-------------------- ppnH- 5 3 -- 25 100 0.02 10 1000 500 0.1 5 2 0.1 1.0 1 0.1 0.1 19 6 15 mppcf 0.5 0.5 31 410 0.2 0.05 5 8340 4170 0.075 2 0.1 1963 Additions +Parts of vapor or gas per million parts of air by volume and 25C and 760 mm. Hg pressure f+Approximate milligrams of particulate per cubic meter of air. A numbers, See Appendix A COMMITTEE ON THRESHOLD LIMIT VALDES FOR 1963 Harry B. Ashe Wayland J. Hayes, Jr. E. J. Baler Keith Jacobson Allan L* Coleman William F. Reindollar H rvey B. Elkins Russell G. Scovill Bernard Grabois Ralph G. Smith Harold R. MacFarland, Consultant Herbert E. Stokinger, Chairman Mitchell R. Zavon OLI 3748 APPENDIX A * A' Benzidine<, Because of high incidence of bladder tumors in man, any exposure, including skin, is extremely hazardous. A2 B-Naphthyiamine. Because of the extremely high incidence of bladder tumors in workers handling this compound, and the inability to control exposures, B-naphthylamine has been prohibited from manufacture, use and other activi ties that involve human contact by the State of Pennsylvania. A3 N^Nitrosodimethylamine. Because of extremely high toxicity and presumed carcinogenic potential of this compound, contact by any route should not be permitted. A^ Teflon (R) decomposition products. At least one identified component of Teflon decomposition products is extremely toxic, but in the absence of more complete toxicity information and suitable analytic methods, a definite threshold limit value is not recommended at this time; but air concentra tions should be minimal. ft A' B-Propiole.ctone. Because of high acute toxicity and demonstrated skin tumor production in animals, contact by any route should be avoided. -10- OLI 3749 APPENDIX B THRESHOLD LIMIT VALUES FOR MIXTURES When two or more hazardous substances are present, their combined effect, rather than that of either individually, 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 fraction, Cl On T-, + T2 + * "Tn exceeds unity, than the threshold limit of the mixture should be considered as being exceeded, C indicates the observed atmospheric concentration, and T^ the corresponding threshold limit, (See Example lA.a). Exceptions to the above rule may be made when there is good reason to believe that the chief effects of the different harmful substances are not in fact additive, but indipendent as when purely local effects on differenct organs of the body are produced by the various components of the mixture. In such cases the threshold limit ordinarily is exceeded only when at least one member of the series (Ci or etc.) itself has a value exceeding unity, (See Example lA.b.). Antagonistic action or potentiation may occur with some combinations of atmospheric contaminants. Such cases at present must be determined individually. Potentiating or antagonistic agents are not necessarily harmful by themselves. Potentiating effects of exposure to such agents by routes other than that of in halation is also possible, e.g. imbibed alcohol and inhaled narcotoc (trichlorethylene). Potentiation is characteristically exhibited ?t high concentrations, less probably at low. When a given operation or process characteristically emits a number of harm ful dusts, fumes, vapors or gasses, it will frequently be only feasible to attempt to evaluate the hazard by measurement of a single substance. In such cases, the threshold limit used for this substance should be reduced by a suitable factor, the magnitude of which will depend on the number, toxicity and relative quantity of the other contaminants ordinarily present. Examples of processes which are typically associated with two or more harm ful atmospheric contaminants are welding, automobile repair, blasting, painting, lacquering, certain foundry operation, diesel exhausts, etc. (Example 2e) -11- OLI 3750 THRESHOLD LIMIT VALDES FOE MTETORES EXAMPLES 1A.. General case, where air is analyzed for each component, a. Additive Effects C 11 Tn Air contains 5 ppm of carbon tetrachloride (TLV, 10), 20 ppm of ethylene dichloride (TLV,50) end lOppm of ethylene dibrond.de, (TLV,25), - + 20 + 10 = M = 1.3 10 50 25 50 Threshold limit is exceeded, b. Independent Effects Air contains 0,15 mg/m^ of lead (TLV,0.2) and 0.7 mg/m^ of sulfuric acid (TLV,1). 0*35 -- r-, nc, 0,7 _ n 0.20 *75' 1 0,7 Threshold limit is not exceeded. IB. Special case when source of contaminant is a mixture and atmospheric composi tion is assumed similar to that of original material, i.e. vapor pressure of each component is the same at the observed temperature. a. Additive Effects, approximate solution. 1. A mixture of equal parts (1) trichloroethylene (TLV, 100), and (2) methyl chloroform (TLV, 350). h. C2 _ 100 350 " Tm C1 = c2 = 1 Cm Solution applicable to "spot" solvent mixture usage, where all or nearly all, solvent evaporates. C1 + Ei ,, Si 100 350 Tm ?C1 20+ --A :. 2C1 700 700 ' *m T_ = lB.b. 700 x 2 s 155 ppm. 9 General Exact Solution for Mixtures of N Components With Additive Effects and Different Vapor Pressures. OLI 3751 IS (1) + -- 4- 4- T-i T2 *'* T (2) c1 + C2 + .... + Cq = T; (2.1) C- C2 C ~ + "+...+ " - 1* By ti: lav of Partial Pressures, (3) C = ap.-; And by Ra' ult1 s Law, (4) Pi = *i Pi* Combine (3) and (4) to obtain (5) Ci = ^iPi0- Combining (1), (2,1), and (5), we obtain (6) FlPl , FgPp 0 + - +. . . sa! (6.1) F.p. + F p 0 +...+ F p 11 22 n*n t = fiP;* F2p`u ip rp n i~n (6.2) or T = 1 =1 i=n FiPi i = 1 F,p I solving for T, T= C= 5: F= a= Threshold limit value in ppm. Vapor concentration in ppm. Vapor pressure of component in solution. Vapor pressure of pure component. Mol fraction of component in solution. A constant of proportionality. Subscripts 1,2 ...n relate the above quantities to components 1,2 ...n, respectively. Subscript i refers to an arbitrary component from 1 to n. Absence of subscript relates the quantity to the "ixture- oil 3752 Solution to be applied when there is a reservoir of the solv'nt mixture whose composition dess not change appreciably by evaporation. UJW&V* U A1 x ljiUITCU-Ly oc?j.ui*ion oi oPcCxlo. c rajjxure Mol, wt. Density T p at 25C 14)1 fraction in half-and half solution by volume Trichloro ethylene (1) 131.4 1.46 g/nl 100 73nnn Hg Ifethylchlorofcrm (2) 133.42 1.33 g/ml 350 125mm Hg FlPl = (0.527) (73) - 38.2 r2P2 = (0.473) (125) = 59.2 0.527 0.473 38.2 + 59.2 = 152^}. 0?o) = (97.4) (350) = 177 38.2 + 2a2 133.8 + 59.2 193.0 100 350 T = 177 ppm (Note difference in T.L.V. when account is taken of vapor pressure and mol fraction in comparison with- above example where such ac count is not taken.) - ..........2 2. A mixture of one part of (1) parathion (TLV, 0*1) and two parts of (2) EPN (TLV, 0.5). C1 + 3 - Cm; C2 = 2C1 0.1 0.5 m cm:= 30., C1 + a. 0.1 + 0.5 7Ci 3C, C.5 3C. `m 11 -1 Tm = hi 7 1C. Independent Effects 1. From naphtha (TLV, 500) containing 10 mole per cent benzene (TLV, 25) the narcotic effects can be considered as approximately the same as that of benzene-free naphtha. The blood effects can be considered as due to the benzene alone. -14- OLI 3753 For intermittent exposure, a TLV of 500 ppm may be used as long as the age concentration does not exceed 25 x 100 = 250 ppm, the TLV based on the 10 benzene content. 2. Diesel engine exhaust contains several irritants, one of which is nitrogen dioxide. A limit of 2 ppm NO- has been found to correlate fairly well with the beginning of subjective (irritation) effects from such gases, although no subjective effects are experienced from NOj alone at 5 ppm, APPENDIX C BASES FOR ASSIGNING LIMITING "C" VALUES* T.L.V. RANGE ppm* or me/m-* 0 to 1 1+ to 10 10+ to 100 100+ to 1000 Permitted Fluctuation Factor of T.L.V. for 5. 10 or 30 min. 3 2 1.5 1.25 Examples Boron triflucride (1 ppm) at 3 ppm if repeatedly encountered for periods of 5, 10, or 30 minutes, may lead to pneumonitis; a nC" listing recommended Ethyl benzene (200 ppm) at 250 ppm if repeatedly encountered for periods of 5 or 10 minutes may prove intolerably irritating to the eyes; a "C" listing recommended * According to this limitation, the presently listed TLVs will or will not be candidates for a nC" (ceiling) listing. 1963 TLVs not coming within this limi tation will bear a "C" before the substance name. Judgment is based on whether the excursions in concentration under the time limits stated may result in a) intolerable irritation, b) chronic or irreversible tissue change, or c) narcosis of sufficient degree to increase accident proneness or materially reduce work efficiency. >15- OLI 3754