Document R92GmXMkYvYLRnbG778zG7V7

sc 008146 LAM009356 :t> u AM < .1 l4M&rii>^<8ir iSVi-nm* .*Wir f.im; j.iim. o< riPMl^'"OTiS"A|roQ>i3liPs'!- H'r n'tyPt/ .) mV'mt&i ,i:ii.-:!islaf-r*?!-- " ;*!- iii:- jr11111i.if|iri.:i|'RiW '.'JJ--.*TlS7Dilj>J{.i !-l;'!`. Atfairamob ^in* ito: .^.ail.RSl *!.' ^^iHiil1 * is? Wr> . '"'-inidzlMtk?.if? 'h\% /sSlijJl-IspaSxfi)/ `"\Q{'j>-v::t no- nVi.-T r.^nSiTiFc^r3rr^ .-iWeW:* fi.i oo.m-'iu:!:; {;viW,v.:jsr.)4pT|Xj^ <ft@iav^i>~-Viir in ...i.v-wr.? -SjiU'iSUP.mmm-* }* <Wmmm^M^vs,0i>m '& 'i>T1;i'it- itTrih>4>il^JitillEIifili' - . < iHiw-'inii w* '.''.It?:!.-: 'WXtKiM* <:Wi!''!lW:- .-.iljtlliyt . L tCflPJ. ^ Elixir < ff(i fi ^ iS'HFi '."J- '& 3 i'f.- .li:J:ii:;l||if!ltjI^ii n>: -i :>s> [<> TLVs Threshold Limit Values tor Chemical Substances in the Work Environment Adopted by ACGIH for 1983-84 ^.iL: -;.-J-.K_!itUT^I11 hT^IIS :5iMr:'cv* AIjMlJ* ; ' . . ."jii^iiii^irr ;<r.sa@SS`: 008"'47 SC LAM009357 1982-83 CHEMICAL SUBSTANCES TLV COMMITTEE Vernon L. Carter, D.V.M., Ohio State University -- Chairman Melvin E. Andersen, Ph.D., USAF B. Dwight Culver, M.D., University of Califomia-lrvine James W. Hammond, University of Texas Trent R. Lewis, Ph.D., NIOSH (returned to member status 5/83) Jesse Lieberman, P.E., USN Floyd A. Madsen, OSHA Frederick T. McDermott, Michigan Dept, of Public Health Walter W. Melvin, Jr., M.D., Sc.D., Colorado State University Mary K. Murphy, OSHA Leonard D. Pagnotto, Massachusetts Dept, of Labor & Industry -- Secretary Ronald S. Ratney, OSHA Meier Schneider, P.E., C.I.H., Metropolitan Water Dis trict of Southern California Robert Spirtas, Dr. PH, National Cancer Institute Vera F. Thomas, Ph.D., University of Miami William D. Wagner, NIOSH (returned to member status 5/83) Elizabeth K. Weisburger, Ph.D., National Cancer Institute CONSULTANTS Paul Gross, M.D. Georg Kimmerle, M.D., German MAK Commission Liaison Ernest Mastromatteo, M.D. James F. Morgan George Roush, Jr., M.D. Marshall Steinberg, Ph. D. Theodore R. Torkelson, Sc.D. Ralph C. Wands Mitchell R. Zavon, M.D. TABLE OF CONTENTS Chemical Substances Preface....................................................................... Threshold Limit Values and Short Term Expo sure Limits.............................................................. Radioactivity.............................................................. Mineral Dusts............................................................. Nuisance Particulates............................................... Notice of Intended Changes..................................... Appendices A. Carcinogens.................................................... B. Substances of Variable Composition......... C. Mixtures: Calculation of TLVs...................... D. Nuisance Particulates.................................... E. Asphyxiants..................................................... F. Conversion of Particle Count to Mass........ G. Chemical Substances Under Study............ H. Registered Trade Names............................... 2 10 35 36 37 38 41 47 48 52 52 53 56 58 Physical Agents Preface....................................................................... Threshold Limit Values Heat Stress...................................................... Ionizing Radiation.................................................. Lasers..................................................................... Noise....................................................................... Impulsive or Impact Noise.................................... Radiofrequency/Microwave Radiation............... Ultraviolet Radiation.............................................. Notice of Intended Changes.................................... Notice of Intent: Lasers..................................................................... Light and Near-Infrared Radiation...................... Airborne Upper Sonic and Acoustic Radiation.. Agents Under Study............................................... 61 62 69 70 80 81 82 86 89 89 89 92 93 0081^8 sc LAM009358 PREFACE CHEMICAL SUBSTANCES Threshold limit values refer to airborne concentra tions of substances and represent conditions under which it is believed that nearly all workers may be re peatedly exposed day after day without adverse ef fect. Because of wide variation in individual suscepti bility, however, a small percentage of workers may experience discomfort from some substances at con centrations at or below the threshold limit; a smaller percentage may be affected more seriously by aggra vation of a pre-existing condition or by development of an occupational illness. Threshold limits are based on the best available information from industrial experience, from experi mental human and animal studies, and, when possi ble, from a combination of the three. The basis on which the values are established may differ from sub stance to substance; protection against, impairment of health may be a guiding factor for some, whereas reasonable freedom from irritation, narcosis, nui sance or other forms of stress may form the basis for others. The amount and nature of the information avail able for establishing a TLV varies from substance to substance; consequently, the precision of the esti mated TLV is also subject to variation and the latest Documentation should be consulted in order to assess the extent of the data available for a given sub stance. These limits are intended for use in the practice of industrial hygiene and should be interpreted and ap plied only by a person trained in this discipline. They are not intended for use, or for modification for use, (1) as a relative index of hazard or toxicity, (2) in the evaluation or control of community air pollution nui sances, (3) in estimating the toxic potential of contin uous, uninterrupted exposures or other extended work periods, (4) as proof or disproof of an existing disease or physical condition, or (5) for adoption by countries whose working conditions differ from those in the United States of America and where substances and processes differ. The TLV-TWA should be used as guides in the control of health hazards and should not be used as fine lines between safe and dangerous concentra tions. 2 In spite of the fact that serious injury is not be lieved likely as a result of exposure to the threshold limit concentrations, the best practice is to maintain concentrations of all atmospheric contaminants as low as is practical. Legal Status. The Threshold Limit Values, as is sued by ACGIH, are recommendations and should be used as guidelines for good practices. Wherever these values (of whatever year) have been used or in cluded by reference in Federal and/or State statutes and registers, the TLVs do have the force and effects of law. "Notice of Intent." At the beginning of each year, proposed actions of the Committee for the forthcom ing year are issued in the form of a "Notice of Intend ed Changes." This Notice provides not only an oppor tunity for comment, but solicits suggestions of substances to be added to the list. The suggestions should be accompanied by substantiating evidence. The list of Intended Changes follows the Adopted Val ues in the TLV booklet. Values listed in parenthesis in the "Adopted" list are to be used during the period in which a proposed change for that Value is listed in the Notice of Intended Changes. Definitions. Three categories of Threshold Limit Values (TLVs) are specified herein, as follows; a) The Threshold Limit Value-Time Weighted Average (TLV-TWA) -- the time-weighted average concentration for a normal 8-hour workday and a 40hour workweek, to which nearly all workers may be repeatedly exposed, day after day, without adverse ef fect. b) Threshold Limit Value-Short Term Exposure Limit (TLV-STEL) -- the concentration to which workers can be exposed continuously for a short period of time without suffering from 1) irritation, 2) chronic or irreversible tissue damage, or 3) narcosis of sufficient degree to increase the likelihood of ac cidental injury, impair self-rescue or materially reduce work efficiency, and provided that the daily TLV-TWA is not exceeded. It is not a separate independent ex posure limit, rather it supplements the time-weighted average (TWA) limit where there are recognized acute effects from a substance whose toxic effects are pri marily of a chronic nature. STELs are recommended only where toxic effects have been reported from high short-term exposures in either humans or ani mals. A STEL is defined as a 15-minute time-weighted average exposure which should not be exceeded at any time during a work day even if the eight-hour 3 008^49 SC LAM009359 sc 008150 time-weighted average is within the TLV. Exposures at the STEL should not be longer than 15 minutes and should not be repeated more than four times per day. There should be at least 60 minutes between succes sive exposures at the STEL. An averaging period other than 15 minutes may be recommended when this is warranted by observed biological effects. c) Threshold Limit Value-Ceiling (TLV-C) -- the concentration that should not be exceeded even in stantaneously. For some substances, e.g., irritant gases, only one category, the TLV-Ceiling, may be relevant. For other substances, either two or three categories may be rel evant, depending upon their physiologic action. It is important to observe that if any one of these three TLVs is exceeded, a potential hazard from that sub stance is presumed to exist. The committee holds to the opinion that limits based on physical irritation should be considered no less binding than those based on physical impair ment. There is increasing evidence that physical irri tation may initiate, promote or accelerate physical im pairment through interaction with other chemical or biologic agents. Time-Weighted Average vs Ceiling Limits. Timeweighted averages permit excursions above the limit provided they are compensated by equivalent excur sions below the limit during the workday. In some in stances it may be permissible to calculate the average concentration for a workweek rather than for a workday. The relationship between threshold limit and permissible excursion is a rule of thumb and in certain cases'may not apply. The amount by which threshold limits 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 ef fects are cumulative, the frequency with which high concentrations occur, and the duration of such periods. All-factors must be taken into consideration in arriving at a decision as to whether a hazardous condition exists. Although the time-weighted average concentration provides the most satisfactory, practical way of moni toring airborne agents for compliance with the limits, there are certain substances for which it is inappro priate. In the latter group are substances which are predominantly fast acting and whose threshold limit is more appropriately based on this particular re sponse. Substances with this type of response are 4 best controlled by a ceiling "C" limit that should not be exceeded. It is implicit in these definitions that the manner of sampling to determine noncompliance with the limits for each group must differ; a single brief sample, that is applicable to a "C" limit, is not appropriate to the time-weighted limit; here, a suffi cient number of samples are needed to permit a timeweighted average concentration throughout a com plete cycle of operations or throughout the work shift. Whereas the ceiling limit places a definite bounda ry which concentrations should not be permitted to exceed, the time-weighted average limit requires an explicit limit to the excursions that are permissible above the listed values. It should be noted that the same factors are used by the Committee in determin ing the magnitude of the value of the STELs, or whether to include or exclude a substance for a "C" listing. Excursion Limits. For the vast majority of sub stances with a TLV, there is not enough toxicological data available to warrant a STEL. Nevertheless, excur sions above the TWA-TLV should be controlled even where the eight-hour TWA is within recommended limits. Earlier editions of the TLV list included such limits whose values depended on the TWA-TLVs of the substance in question. While no rigorous rationale was provided for these particular values, the basic concept was intuitive: in a well controlled process exposure, excursions should be held within some reasonable limits. Unfortunately, neither toxicology nor collective industrial hygiene experience provide a solid basis for quantifying what those limits should be. The approach here is that the maximum recommended excursion should be related to the variability generally observed in actual industri al! processes. Leidel, Busch and Crouse,* in review ing large numbers of industrial hygiene surveys con ducted by NIOSH, found that short-term exposure measurements were generally log normally distrib uted with geometric standard deviations mostly in the range of 1.5 to 2.0. While a complete discussion of the theory and properties of the log normal distribution is beyond the scope of this section, a brief description of some important terms is presented. The measure of central tendency in a log normal distribution is the antilog of the mean logarithm of the sample values. The distri- 'Leidel, N.A., K.A. Busch and W.E. Crouse: Exposure Measurement, Action Level and Occupational Environmental Variability. NIOSH Pub. No. 76-131 (December 1975). 5 LAM009360 bution is skewed and the geometric mean is always smaller than the arithmetic mean by an amount which depends on the geometric standard deviation. In the log normal distribution, the geometric standard devia tion (sd,,) is the antilog of the standard deviation of the sample value logarithms and 68.26% of all values lie between rr^lsd,, and m,, x sd,,. If the short-term exposure values in a given situa tion have a geometric standard deviation of 2.0, 5% of all values exceed 3.13 times the geometric mean. If a process displays a variability greater than this, it is not under good control and efforts should be made to restore control. This concept is the basis for the new excursion limit recommendations which are as fol lows: Short-term exposures should exceed three times the TLV-TWA for no more than a total of 30 min utes during a work day and under no circum stances should they exceed five times the TLV, provided that the TLV-TWA is not exceeded. The approach is a considerable simplification of the idea of the log normal concentration distribution but is considered more convenient to use by the prac ticing industrial hygienist. If exposure excursions are maintained within the recommended limits, the geo metric standard deviation of the concentration mea surements will be near two and the goal of the recom mendation will be accomplished. When the toxicologic data for a specific substance are available to establish a STEL, this value takes pre cedence over the excursion limit regardless of whether it is more or less stringent. "Skin" Notation. Listed substances followed by the designation "Skin" refer to the potential contribu tion to the .overall exposure by the cutaneous route including mucous membranes and eye, either by air borne, or more particularly, by direct contact with the substance. Vehicles can alter skin absorption. Little quantitative data are available describing ab sorption of vapors and gases through the skin. The rate of absorption is a function of the concentration to which the skin is exposed. Substances having a skin notation and a low TLV may present a problem at high airborne concentra tions, particularly if a significant area of the skin is exposed for a long period of time. Protection of the respiratory tract, while the rest of the body surface is exposed to a high concentration, may present such a situation. Biological monitoring should be considered to de- 6 termine the relative contribution of dermal exposure to the total dose. This attention-calling designation is intended to suggest appropriate measures for the prevention of cutaneous absorption so that the threshold limit is not invalidated. Mixtures. Special consideration should be given also to the application of the TLVs in assessing the health hazards which may be associated with expo sure to mixtures of two or more substances. A brief discussion of basic considerations involved in devel oping threshold limit values for mixtures, and meth ods for their development, amplified by specific ex amples are given in Appendix C. Nuisance Particulates. In contrast to fibrogenic dusts which cause scar tissue to be formed in lungs when inhaled in excessive amounts, so-called "nui sance" dusts have a long history of little adverse ef fect on lungs and do not produce significant organic disease or toxic effect when exposures are kept under reasonable control. The nuisance dusts have also been called (biologically) "inert" dusts, but the latter term is inappropriate to the extent that there is no dust which does not evoke some cellular response in the lung when inhaled in sufficient amount. Howev er, the lung-tissue reaction caused by inhalation of nuisance dusts has the following characteristics: (1) The architecture of the air spaces remains intact. (2) Collagen (scar tissue) is not formed to a significant extent. (3) The tissue reaction is potentially reversible. Excessive concentrations of nuisance dusts in the workroom air may seriously reduce visibility, may cause unpleasant deposits in the eyes, ears and nasal passages (Portland Cement dust), or cause injury to the skin or mucous membranes by chemical or me chanical action per se or by the rigorous skin cleans ing procedures necessary for their removal. A threshold limit of 10 mg/m3, or 30 mppcf, of total dust < 1% quartz, or, 5 mg/m3 respirable dust is rec ommended for substances in these categories and for which no specific threshold limits have been as signed. This limit, for a normal workday, does not apply to brief exposures at higher concentrations. Neither does it apply to those substances which may cause physiologic impairment at lower concentra tions but for which a threshold limit has not yet been adopted. Some nuisance particulates are given in Ap pendix D. Simple Asphyxiants --"Inert" Gases or Vapors. A number of gases and vapors, when present in high concentrations in air, act primarily as simple asphyx- 7 Sc LAM009361 iants without other significant physiologic effects. A TLV may not be recommended for each simple as phyxiant because the limiting factor is the available oxygen. The minimal oxygen content should be 16 percent by volume under normal atmospheric pres sure (equivalent to a partial pressure, pfe of 135 mm Hg). Atmospheres deficient in 02 do not provide ade quate warning and most simple asphyxiants are odorless. Several simple asphyxiants present an ex plosion hazard. Account should be taken of this fac tor in limiting the concentration of the asphyxiant. Specific examples are listed in Appendix E. Physical Factors. It is recognized that such physi cal factors as heat, ultraviolet and ionizing radiation, humidity, abnormal pressure (altitude) and the like may place added stress on the body so that the ef fects from exposure at a threshold limit may be al tered. Most of these stresses act adversely to increase the toxic response of a substance. Although most threshold limits have built-in safety factors to guard against adverse effects to moderate deviations from normal environments, the safety factors of most sub stances are not of such a magnitude as to take care of gross deviations. For example, continuous work at temperatures above 90F, or overtime extending the workweek more than 25%, might be considered gross deviations. In such instances judgment must be exer cised in the proper adjustments of the Threshold Limit Values. Biologic Umit Values (BLVs). Other means exist and may be necessary for monitoring worker expo sure other than reliance on the Threshold Limit Val ues for industrial air, namely, the Biologic Limit Val ues. These values represent limiting amounts of substances (or their effects) to which the worker may be exposed without hazard to health or well-being as determined in his tissues and fluids or in his exhaled breath. The biologic measurements on which the BLVs are based can furnish two kinds of information useful in the control of worker exposure: (1) measure of the individual worker's over-all exposure; (2) mea sure of the worker's individual and characteristic re sponse. Measurements of response furnish a superior estimate of the physiologic status of the worker, and may be made of (a) changes in amount of some criti cal biochemical constituent, (b) changes in activity of a critical enzyme, (c) changes in some physiologic function. Measurement of exposure may be made by (1) determining in blood, urine, hair, nails, in body tis sues and fluids, the amount of substance to which the worker was exposed; (2) determination of the amount 8 of the metabolite(s) of the substance in tissues and fluids; (3) determination of the amount of the sub stance in the exhaled breath. The biologic limits may be used as an adjunct to the TLVs for air, or in place of them. The BLVs, and their associated procedures for determining compliance with them, should thus be regarded as an effective means of providing health surveillance of the worker. Tests are available (J. Occup. Med. 75:564, 1973; Ann. N.Y. Acad. Sci. 151, Art. 2:968, 1968) that may be used to detect those individuals hypersusceptible to a variety of industrial chemicals (respiratory irritants, hemolytic chemicals, organic isocyanates, carbon disulfide). Unlisted Substances. Many substances present or handled in industrial processes do not appear on the TLV list. In a number of instances the material is rare ly present as a particulate, vapor or other airborne contaminant, 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 Committee. Other substances, of low toxicity, could be Included in Appendix D pertaining to nui sance particulates. This list (as well as Appendix E) is not meant to be all inclusive; the substances serve only as examples. In addition there are some substances of not in considerable toxicity, which have been omitted pri marily because only a limited number of workers (e.g., employees of a single plant) are known to have potential exposure to possibly harmful concentra tions. Trade names. Because many chemical substances are marketed under several trade names, the trade names have been replaced with their generic equiva lent in the alphabetical listing. Appendix H was creat ed to ease this transition and the CAS number ap pears with the generic name to aid identification. Operational Guidelines: The ACGIH Board of Directors has adopted operational guidelines for the Chemical Substances TLV Committee. These guide lines prescribe: charge, authority, policies, member ship, organization, and operating procedures. The policies include the appeals procedures. Copies of the guidelines document are available from the Publi cations Office at a cost of $5 per copy. 9 - SC 008152 LAM009362 Substance [CAS#] ADOPTED VALUES TWA STEL ppm"' mg/m3*' ppm' mg/m3*' Acetaldehyde [75-07-0]..... 100 180 Acetic acid [64-19-7]....... 10 25 Acetic anhydride [108-24-7].................... C 5 C 20 Acetone [67-64-1]............ 750 1,780 Acetonitrile [75-05-8] -- Skin............................ 40 70 Acetylene [74-86-2].......... E -- Acetylene dichloride, see 1, 2-Dichloroethylene Acetylene tetrabromide [79-27-6] ..................... 1 15 Acetylsalicylic acid (Asprin) [50-78-2]..................... -- 5 Acrolein [107-02-8].......... 0.1 0.25 Acrylamide [79-06-1] -- Skin............................ -- 0.3 Acrylic add [79-10-7]....... 10 30 ^Acrylonitrile [107-13-1] -- Skin............................ (2, Ala) (4.5, Ala) Aldrin [309-00-2] -- Skin.. -- 0.25 Allyl alcohol [107-18-6] - Skin............................ 2 5 Allyl chloride [107-05-1]... 1 3 Allyl glycidyl ether (AGE) [106-92-3] --Skin....... 5 22 Allyl propyl disulfide [2179-59-1]................. 2 12 a-Alumina [1344-28-1]..... -- D Aluminum [7429-90-5] Metal & oxide............... Pyro powders............... -- -- 10 5 Welding fumes............. -- 5 Soluble salts................ -- 2 Alkyls (NOCt)............... -- 2 4-Aminodiphenyl [92-67-1] -- Skin........................ -- Alb 2-Aminoetnanol, see Ethanolamine 2-Amtnopyndine [504-29-0].................... 0.5 2 3-Amino 1,2, 4-triazole, see Amitrol Amitrol [61-82-5]............. A2 A2 Ammonia [7664-41-7]...... 25 18 150 15 -- 1,000 60 -- 1.5 -- 0.3 -- -- -- -- 4 2 10 3 -- -- -- -- -- -- -- 2 -- 35 270 37 '--2,375 105 -- 20 -- 0.8 0.6 -- -- 0.75 10 6 44 18 20 20 -- -- -- -- Alb 4 -- 27 Capital letters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 35. tSee Notices of Intended Changes. tNOC = Not otherwise classified. 10 Substance [CAS#] ADOPTED VALUES TWA STEL ppm0' mg/rn^" ppir' mg/m3*' Ammonium chloride fume [12125-02-9]................ -- Ammon urn sulfamate [7773-06-0]................. -- n-Amyl acetate [628-63-7]. 100 sec-Amyl acetate [626438-0].................... 125 Aniline [62-53-3] & homologues -- Skin..... 2 Anisidine [29191-52-4] (o-, p-isomers) -- Skin....... 0.1 Antimony [7440-36-0] & compounds, as Sb....... -- Antimony trioxide [1309-64-4] Handling and use, as Sb Production.................... ANTU [86-88-4]............... __ -- -- Argon [7440-37-1]........... E Arsenic [7440-38-2] & soluble compounds, as As................................ __ Arsenic trioxide production [1327-53-3]................. -- Arsine [7784-42-1]........... 0.05 Asbestos [1332-21-4], see MINERAL DUSTS.......... -- Asphalt (petroleum) fumes [8052-424]................. 'Atrazine [1912-24-9]......... -- -- Azinphos-methyl [86-50-0] -- Skin -- Barium [7440-39-3], soluble compounds, as Ba................................ -- Benomyl [17804-35-2]..... 0.8 Benzene [71-43-2]........... 10, A2 Benzidine [92-87-5] -- Skin............................ __ p-Benzoquinone, see Quinone Benzoyl peroxide [94-36-0] Benzo(a)pyrene [50-32-8].. __ -- Benzyl chloride [10044-7], 1 10 -- 10 -- 530 150 670 150 10 5 0.5 -- 0.5 __ 0.5 __ A2 -- 0.3 __ -- __ 0.2 __ A2 __ 0.2 -- Ala __ 5-- 5 __ 0.2 __ 0.5 10 30, A2 Alb __ 1.3 25, A2 _ 5 __ A2 -- 5-- 20 20 800 800 20 -- ` __ __ __ 0.9 __ __ __ -- Ala 10 __ 0.6 __ 15 75, A2 Alb __ A2 -- Capital letters A. B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 35. *1983 Addition 11 008153 LAM009363 Substance [CAS#] ADOPTED VALUES TWA STEL ppm*' tng/m^" ppm" mg/m3*' Beryllium [7440-41-7]...... __ 0.002, A2 __ Bphenyl [92-52-4]........... 0.2 1.5 0.6 Bismuth teiluride [1304-82-1]................. Se-doped ..................... __ __ 10 __ 5 __ Borates, tetra, sodium salts [1303-96-4], Anhydrous.................... Decahydrate................. Pentahydrate................ Boron oxide [1303-86-2]... __ -- __ __ 1 __ 5 __ 1 __ 10 __ Boron tribromide [10294-33-4]................ 1 10 3 Boron trifluoride [7637-07-2]................. Cl C 3 __ Bromacil [314-40-9]......... 1 10 2 Bromine [7726-95-6]....... 0.1 0.7 0.3 Bromine pentafluoride [7789-30-2]................. 0.1 0.7 0.3 Bromochloromethane, see Chlorobromomethane Bromoform [75-25-2] -- Skin............................ 0.5 5 __ 1,3-Butadiene [106-99-0]. (1,000) (2,200) (1,250) Butane [106-97-8]............ 800 1,900 -- Butanethiol, see Butyl mercaptan 2-Butanone, see Methyl ethyl ketone (MEK) 2-Butoxyethanol [111-76-2] --Skin....... 25 120 75 n-Butyl acetate [123-86-4]. 150 710 200 sec-Butyl acetate [105464].................... 200 950 250 tert-Butyl acetate [540-88-5].................... Butyl acrylate[141-32-2]... 200 10 950 250 55 __ n-Butyl alcohol [71-36-3] -- Skin......................... C 50 C 150 __ sec-Butyl alcohol [78-92-2] 100 305 150 tert-Butyl alcohol [75-65-0] 100 300 150 Butylamine [109-73-9] -- Skin............................ C5 C 15 _ tert-Butyl chromate, as Cr03 [1189-85-1] -- Skin............................ -- C0.1 -- 4 20 10 __ -- __ 20 30 __ 20 2 2 __ (2,750) -- 360 950 1,190 1,190 __ __ 455 450 _ -- Capita] letters A, B, 0 & E refer to Appendices; C denotes ceiling limit. Footnotes (a thrv t) see Page 35. $See Notice of Intended Changes. 12 Substance [CAS#] ADOPTED VALUES TWA STEL ppm01 mg/m3*' ppnf1 mg/m3*" n-Butyl glycidyl ether (BGE) [2426-08-6]................. n-Butyl lactate [138-22-7].. Butyl mercaptan [109-79-5].................... o-sec-Butylphenol [89-72-5] --Skin......... p-tert-Butyltoluene [98-51-1] Cadmium [744043-9] Dust & salts, as Cd...... Cadmium oxide [1306-19-0] Fume, as Cd................. * Production.................... Calcium carbonate/ marble [1317-65-3]................. Calcium cyanamide [156-62-7].................... Calcium hydroxide [1305-62-0]................. Calcium oxide [1305-78-8] Calcium silicate [1344-95-2]................. Camphor, synthetic [76-22-2]..................... Caprolactam [105-60-2] Dust............................. Vapor........................... Captafol [2425-06-1] -- Skin............................ Captan [133-06-2]............ Carbaryl [63-25-2]........... Carbofuran [1563-66-2].... Carbon black [1333-864].. Carbon dioxide [124-38-9]. Carbon disulfide [75-15-0] -- Skin......................... Carbon monoxide [630-08-0].................... Carbon tetrabromide [558-134].................... 25 5 0.5 5 10 -- -- -- -- -- -- -- -- 2 -- 5 -- -- -- -- -- 5,000 10 50 0.1 135 -- 25 -- 1.5 -- 30 -- 60 20 0.05 -- C 0.05 0.05 D -- -- -- 0.5 -- 5-- 2-- D-- 12 3 1-- 20 10 0.1 5 5 0.1 3.5 9,000 -- -- -- -- -- 15,000 30 -- 55 400 1.4 0.3 -- -- -- -- 120 0.2 -- -- 20 1 -- -- -- 18 3 40 -- 15 10 -- 7 27,000 --* 440 4 Capital letters A, B, D & E refer to Appendices; C denotes cSng limit. Footnotes (a thru f) see Page 35. "1983 Addition. 13 sc 008154 LAM009364 sc 008155 ADOPTED VALUES Substance TWA STEL [CAS #] ppm"' mg/m3'" pptff" mg/m3"' Carbon tetrachloride [56-23-51--Skin........ 5, A2 30, A2 20, A2 Carbonyl chloride, see Phosgene Carbonyl fluoride [353-50-41.................... 2 55 Catechol (Pyrocatechol) [120-80-9].................... 5 20 -- Cellulose (paper fiber) [9004-34-6]................. -- D-- Cesium hydroxide [21351-79-1]................ -- 2-- Chlordane [57-74-91- Skin............................ -- 0.5 -- Chlorinated camphene [8001-35-2] -- Skin..... -- 0.5 -- Chlorinated diphenyl oxide [55720-99-5]................ -- 0.5 -- Chlorine [7782-50-5]....... 1 33 Chlorine dioxide [10049-04-4]................ 0.1 0.3 . 0.3 Chlorine trifluoride [7790-91-2]................. C0.1 C 0.4 -- Chloroacetaldehyde [107-20-0].................... Cl C3 -- a-Chloroacetophenone [532-27-4] (Phenacyl chloride)...................... 0.05 0.3 -- Chloroacetyl chloride [79-04-9]..................... 0.05 0.2 -- Chlorobenzene [108-90-7] (Monochlorobenzene).... 75 350 -- *o-Chlorobenzylidene malononitrile [2698-41-1]-- Skin..... C 0.05 C0.4 -- Chlorobromomethane [74-97-5] ..................... 200 1,050 250 2-Chloro-1, 3-butadiene, see/3 Chloroprene Chlorodifluoromethane [75-45-6]..................... 1,000 3,500 1,250 Chlorodiphenyl (42% Chlorine) [53449-21-9] -- Skin......................... -- 1-- 125, A2 15 -- 20 -- 2 1 2 9 0.9 -- -- -- -- -- -- 1,300 4,375 2 ------Substance 1 [CAS#] ADOPTED VALUES TWA STEL ppm01 mg/m38' ppm01 mg/m38' Chlorodiphenyl (54% Chlorine) [11097-69-1] -- Skin......................... -- 0.5 1-Chioro, 2,3-epoxy-prapane, see Epichlorohydnn -- 1 2-Chloroethanol, see Ethylene chlorohydrin Chloroethvlene, see Vinyl chloride Chloroform [67-66-3]....... 10, A2 bis-Chloromethyl ether [542-88-1].................... 0.001, Ala 50, A2 50, A2 225, A2 0.005, Ala -- 'Chloromethyl methyl ether [107-30-2].................... A2 A2 -- 1-Chtoro-1 -nitropropane [600-25-9].................... 2 10 -- Chloropentafluoroethane [76-15-3]..................... 1,000 Chloropicrin [76-06-2]...... 0.1 6,320 0.7 -- 0.3 /3-Chloroprene [126-99-8] -- Skin......................... 10 45 -- o-Chlorostyrene [1331-28-8]................. 50 285 ' 75 o-Chlorotoluene [95-49-8] -- Skin......................... 50 250 75 2-Chloro- 6-(trichloromethyl) pyridine, see Nitrapynn 2 430 J/5 Chlorpyrifos [2921-88-2] -- Skin......................... Chromite ore processing (Chromate), as Cr......... Chromium [7440-47-3] Metal........................... Chromium (II) compounds, as Cr........................... -- 0.2 -- 0.05, Ala -- 0.5 -- 0.5 -- -- -- -- 0.6 -- Chromium (III) compounds, as Cr......... -- 0.5 -- -- Chromium (VI) compounds, as Cr Water soluble............... Certain water insoluble.. -- 0.05 -- 0.05, Ala -- -- -- -- Chromyl chloride [14977818]................ 0.025 0.15 -- Chrysene [218-01-9]......... A2 A2 -- Clopidol [2971-908]......... -- 10 -- 20 Capital letters A, B, 0 4 E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 35. *1983 Addition. 14 Capita! letters A, B, D S E refer to Appendices; C denotes ceiling limit. Footnotes (a thru 1) see Page 35. *1983 Addition. 15 LAM009365 sc 008156 Substance [CAS #] AMPTH) VALUES TWA STEL PPm0' mg/m36' ppm" mg/m31" Coal tar pitch volatiles [800745-2], as benzene solubles....................... 0.2. Ala tCobalt [7440484], as Co metal, dust & fume...... (0.1) 'Cobalt carbonyl [00000-00-0], as Co..... _ 0.1 `Cobalt hydrocarbonyl [16842-03-8], as Co..... 0.1 Copper[7440-50-8] Fume........................... 0.2 Dusts & mists, as Cu.... -- 1-- 2 Cotton dust, raw............... -- 0.2*' -- 0.6 Cresol [1319-77-3], all isomeres -- Skin.......... 5 22 Crotonaldehyde [123-73-9] 2 66 18 Crufomate [299-86-5]...... -- 5-- 20 Cumene [98-82-8] -- Skin. 50 245 75 365 Cyanamide [420-04-2]...... -- 2-- -- Cyanides [151-50-8; 143-33-9], as CN -- Skin............................ 5 Cyanogen [460-19-5]....... 10 20 -- -- Cyanogen chloride [506-774].................... C 0.3 C 0.6 _ Cyclohexane [110-82-7].... 300 1,050 375 1,300 Cydohexanol [108-93-0]... 50 200 -- -- Cydohexanone [108-94-1]. 25 100 100 400 Cydohexene [110-83-8].... 300 1,015 -- -- Cydohexylamine [108-91-8] --Skin....... 10 40 Cydonite [121-824] -- Skin............................ 1.5 3 Cydopentadiene [542-92-7].................... 75 200 150 400 Cydopentane [287-92-3]... 600 1,720 900 2,580 Cyhexatin [13121-70-5].... -- 5-- 10 2, 4-D [94-75-7] .............. -- 10 -- 20 DDT (Dichlorodiphenyl- trichloroethane) [50-29-3] ..................... 1 3 Capital letters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 35. *1983 Addition. $See Notice of Intended Changes, k) Seep. 38. 16 Substance [CAS#] ADOPTED VALUES TWA STEL ppm" mg/m3" ppm"1 mg/m3'" Decaborane [1770241-9] -- Skin......................... 0.05 0.3 Demeton [806548-3] -- Skin............................ 0.01 0.1 Diacetone alcohol [12342-2].................... 50 240 1, 2-Diaminoethane, see Ethylenediamine Diazinon [33341-5] -- Skin............................ -- 0.1 Diazomethane [334-88-3].. 0.2 0.4 Diborane [1928745-7]..... 0.1 0.1 1,2-Dibromoethane, see Ethylene dibromide 2-N-Dibutylaminoethanol [102-81-8] --Skin....... 2 14 Dibutyl phosphate............ 1 5 Dibutyl phthalate [84-74-2] -- 5 Dichloroacetylene [7572-294]................. C0.1 C 0.4 o-Dichlorobenzene [95-50-1] C 50 C 300 p-Dichlorobenzene [10646-7].................... 75 450 3, 3'-Dichlorobenzidine [91-94-11] --Skin....... -- A2 Dichlorodifluoromethane [75-71-8]..................... 1,000 4,950 1, 3-Dichloro-5,5-dimethyl hydantoin [118-52-5].... -- 0.2 1,1-Dichloroethane [75-34-3] ..................... 200 810 1, 2-Dichloroethane, see Ethylene dichloride 1,1 -Dichloroethylene, see Vmyiidene chloride 1, 2-Dichloroethylene [540-59-0].................... 200 790 Dichloraethyl ether [111444] --Skin....... 5 30 Dichlorofluoromethane [75434]..................... 10 40 Dichloromethane, see Methylene chloride 1,1 -Dichtoro-1 -nitroethane [594-72-9].................... 2 10 1, 2-0ichloropropane, see Propylene dichloride Dichloropropene [542-75-6] -- Skin....... 1 5 0.15 0.03 75 -- -- -- 4 2 -- -- 110 -- 1,250 -- 250 250 10 -- 10 10 0.9 0.3 360 0.3 -- -- 28 10 10 -- -- 675 A2 6,200 0.4 1,010 1,000 60 -- 60 50 Capital letters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 35. 17 LAM009366 Substance [CAS #] ADOPTED VALUES TWA STB. ppnf' mg/m*41 ppiff" mg/m34' 2,2-Dichloropropionic acid [75-99-0]..................... 1 6-- Oichlorotetrafluoroethane [76-14-2]..................... 1,000 7,000 1,250 Dichlorvos [62-73-7] -- Skin............................ 0.1 1 0.3 Dicrotophos [141-66-2] -- Skin............................ -- 0.25 -- Dicydopentadiene [77-73-6] ..................... 5 30 -- Dicydopentadieny! iron [102-54-5].................... -- 10 -- Oieldrin [60-57-1] -- Skin . -- 0.25 -- Diethanolamine [111-42-2] 3 15 -- Diethylamine [109-89-7]... 10 30 25 Diefhylaminoethanol [100-37-8] --Skin....... 10 50 -- Diethylene triamine [111-40-0] -- Skin....... 1 4-- Diethyl ether, see Ethyl ether Diethyl ketone [96-22-0]... 200 705 Diethyl phthalate [84-66-2] -- 5-- Difluorodibromomethane [75-61-6]..................... 100 860 150 Diglyddyl ether (DGE) [2238-07-5]................. 0.1 0.5 -- Dihydroxybenzene, see Hydroquinone Diisobutyl ketone [108-83-8].................... 25 150 -- Ditsopropylamine [108-18-9] --Skin....... 5 20 -- Dimethoxymethane, see Methylal Dimethyl acetamide [127-19-5] --Skin....... Dimethylamine [124-40-3]. 10 10 35 15 18 -- Dimethylaminobenzene, see Xylidene Dimethylaniline [121-69-7] (N, N-Dimethylaniline) -- Skin......................... 5 25 10 Dimethylbenzene, see Xylene Dimethyl carbamyl chloride [79-44-7] ..................... A2 A2 -- Dimethyl-1, 2-dibromo-2-dichloroethyl phosphate , see Naled Dimethylformamide [68-12-2]--Skin......... 10 30 20 -- 8,750 3 -- -- 20 0.75 -- 75 -- -- 10 1,290 -- -- -- 50 -- 50 -- 60 Capital letters A, B, D, & E refer to Appendices; C denotes ceiling limit. Footnotes (a thm f) see Page 35. 18 Substance [CAS #] ADOPTED VALUES TWA STEL ppm01 mg/m3 ppnr" mg/m3 2, 6-Dimethyi-4-heptanone, see Diisobutyl ketone 1,1-Dimethylhydrazine [57-14-7] -- Skin......... 0.5, A2 1, A2 1, A2 2, A2 Dimethylphthalate [131-11-3].................... -- 5-- 10 Dimethyl sulfate [77-78-1] -- Skin......................... 0.1, A2 Dinitolmide [148-01-6]..... -- 0.5, A2 5 -- -- -- 10 Dinitrobenzene [528-29-0] (all isomers) -- Skin..... 0.15 1 0.5 3 Dinitro-o-cresol [534-52-1] -- Skin......................... -- 0.2 -- 0.6 3, 5-Dinitro-o-toluamide, see Dinitolmide Dinitrotoluene [121 -14-2] -- Skin......................... -- 1.5 -- 5 Dioxane, tech, grade [123-91-1] --Skin....... 25 90 100 360 Dioxathion [78-34-2] -- Skin............................ -- 0.2 -- -- Diphenyl, see Biphenyl Diphenylamine [122-39-4]. _ 10 20 Diphenylmettiane diisocyanate, see Methylene bisphenyl isocyanate Dipropylene glycol methyl ether [34590-94-8]....... 100 600 150 900 Dipropyl ketone [123-19-3] 50 235 -- -- Diquat [85-00-7]............... *-- 0.5 *"* 1 Di-sec, octyl phthalate [117-81-7] (Di-2-ethylhexylphthalate).............. _ 5_ 10 Disulfiram [97-77-8]......... -- 2-- 5 Disulfoton [298-04-4]....... -- 0.1 -- 0.3 2, 6-Ditert. butyl-p-cresol [128-37-0].................... -- 10 -- 20 Diuron [330-54-1]............ -- 10 -- -- Divinyl benzene [108-57-6] Emery [112-62-9]............ 10 -- 50 -- D-- -- 20 Endosulfan [115-29-7] -- Skin............................ Endrin [72-20-8] -- Skin... -- -- 0.1 -- 0.1 03 0.3 Epichlorohydrin [106-89-8] -- Skin........................ EPN [2104-64-5] -- Skin .. 2 -- 10 5 0.5 -- 20 2 1, 2-Epoxypropane, see Propylene oxide 2, 3-Epoxy-1-propanol, see Glycidol Ethane [74-84-0].............. E -- -- -- Capital letters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 35. 19 SC 008157 LAM009367 Substance [CAS #] ADOPTED VALUES TWA STEL ppm01 mg/m^' ppnf1 mg/m31" Ethanethiol, see Ethyl mercaptan Ethanolamine [141-43-5]... 3 86 15 Ethion [563-12-2] -- Skin . -- 0.4 -- -- 2-Ethoxyethanol [110-80-5] -- Skin......................... (50) (185) (100) (370) 2-Ethoxyethyl acetate [111-15-9] --Skin....... (50) (270) (100) (540) Ethyl acetate [141 -78-6].... 400 1,400 -- -- Ethyl acrylate [140-88-5] -- Skin......................... 5 20 25 100 Ethyl alcohol (Ethanol) [64-17-5]..................... 1,000 1,900 _ Ethylamine [75-04-7]....... 10 18 -- -- _Ethyl amyl ketone [41-85-5]..................... 25 130 _ Ethyl benzene [100-41-4].. 100 435 125 545 Ethyl bromide [74-96-4].... 200 890 250 1,110 Ethyl butyl ketone [106-35-4].................... 50 230 75 345 Ethyl chloride [75-00-3].... 1,000 2,600 1,250 3,250 Ethylene [74-85-1]........... E -- -- -- Ethylene chlorohydrin [107-07-3] --Skin....... Cl C3 _ Ethylenediamine [107-15-3].................... 10 25 Ethylene dibromide [106-93-4] - Skin....... A2 A2 _ _ Ethylene dichloride [107-06-2].................... 10 40 15 60 _Ethylene glycol [107-21 -1 ] $ Particulate.................... _ (10) (20) Vapor........................... C 50 C 125 -- -- 'Ethylene glycol dinitrate [628-96-6] *-- Skin....... 0.05 0.3 (0.1) (0.6) Ethylene glycol methyl ether acetate, see 2-Melhoxyethyl acetate Ethylene oxide [75-21-8]... (10) (20) -- -- Ethyleneimine [151-56-4] -- Skin......................... 0.5 1 Ethyl ether [60-29-7]......... 400 1,200 500 1,500 Ethyl formate [109-94-4]... 100 300 150 450 Ethylidene chloride, see 1,1-Dichloroethane Ethylidene norbornene [16219-75-3]................ C 5 C 25 Capital letters A, B, D & E refer to Appendices; C denotes celling limit. Footnotes (a thru f) see Page 35. *1983 Addition. See Notice of Intended Changes. 20 Substance [CAS #] ADOPTED VALUES TWA STB. ppm-1 mg/ti/' ppm-' mg/m^ Ethyl mercaptan [75-08-1]. 0.5 12 N-Ethytmorpholine [100-74-3] --Skin....... 5 23 20 Ethyl silicate [78-10-4]..... 10 85 30 Fensulfothion [115-90-2]... -- 0.1 -- * Fenthion [55-38-9] -- Skin -- 0.2 -- Ferbam [14484-64-1]....... -- 10 -- Ferrovanadium dust [12604-58-9]................ -- 1-- Fibrous10 glass dust.......... Fluorides, asF................. -- -- 10 -- 2.5 -- Fluorine [7782-41 -4]......... 1 22 Fluorotrichloromelhane, see Trichlorofluoromethane Fonofos [944-22-9] -- Skin............................ -- 0.1 -- Formaldehyde [50-00-0],... (C 2) (C 3) -- Formamide [75-12-7]....... 20 30 30 Formic acid [64-18-6]...... 5 9-- Furfural [98-01-1]--Skin. 2 8 10 Furfuryl alcohol [98-00-0] -- Skin......................... 10 40 15 Gasoline [8006-61-9]....... 300 900 500 Germanium tetrahydride [7782-65-2]................. 0.2 0.6 0.6 Glass, fibrous or dust, see Fibrous glass dust Glutaraldehyde [111-30-8]. C0.2 C 0.7 -- Glycerin mist [56-81 -5]..... -- D-- Glycidol [556-52-5].......... 25 75 100 Glycol monoethyl ether, see 2-Ethoxyelhanol Graphite (Natural) [7782-42-5], see MINERAL DUSTS Graphite (Synthetic).......... -- D-- Gypsum [10101-44]....... -- D-- Hafnium [7440-58-6]....... -- 0.5 -- Helium [7440-59-7].......... E -- Heptachlor [76-44-8] -- Skin............................ -- 0.5 Heptane [142-82-5] (n-Heptane)................. 400 1,600 500 2-Heptanone, see Methyl n-amyl ketone 3-Heptanone, see Ethyl butyl ketone Hexachlorobutadiene [76-68-3]..................... 0.02, A2 0.24, A2 -- 3 95 255 -- -- 20 3 -- -- 4 -- -- 45 -- 40 60 1,500 1.8 -- -- 300 -- 20 1.5 -- 2 2,000 -- Capital letters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 35. `1983 Addition. See Notice of Intended Changes. 21 008158 LaM00936Q sc 008159 Substance [CAS #] ADOPTED VALUES TWA STEL ppm01 mg/m3*" ppm01 mg/m3111 Hexachloro cyclopen ta- diene [77-47-4]............ 0.01 0.1 0.03 Hexactiloroethane [67-72-1]..................... 10 100 ___ HexactiloronaphthaJene [1335-87-1] --Skin..... __ 0.2 ___ Hexafluoroacetone [684-16-2] - Skin....... 0.1 0.7 0.3 Hexamefhyl phosphoramide [680-31-9] -- Skin....... A2 A2 _ Hexane (n-Hexane) [110-54-3].................... 50 180 __ Other isomeres............ 500 1,800 1,000 2-Hexanone, see Methyl n-butyl ketone Hexone, see Methyl isobutyl ketone sec-Hexyl acetate [142-92-7].................... 50 300 Hexylene glycol [107-41-5] C25 C 125 -- Hydrazine [302-01-2] -- Skin............................ 0.1, A2 Hydrogen [1333-74-0]...... E 0.1.A2 -- __ -- Hydrogenated teipbenyls [92-94-4]..................... 0.5 5_ Hydrogen bromide [10035-10-6]................ 3 10 ___ Hydrogen chloride [7647-01-0]................. C5 C7 _ _Hydrogen cyanide [74-90-8] --Skin......... CIO CIO Hydrogen fluoride [7664-39-3], as F......... 3 2.5 6 Hydrogen peroxide [7722-84-1]................. 1 1.5 2 Hydrogen selenide [7783-07-5], as Se....... 0.05 0.2 Hydrogen sulfide [7783-06-4]................. 10 14 15 Hydroquinone [123-31-9].. -- 2-- 4-Hydroxy-4-methyl-2-pentanone, see Diacetone alcohol 2-Hydroxypropyl acrylate [999-61-1] --Skin....... 0.5 3_ Indene [95-13-6].............. 10 45 15 Indium [7440-74-6] & compounds, as In......... _ 0.1 0.3 __ 0.6 2 ___ 3,600 -- __ -- ___ __ ___ __ 5 3 ___ 21 4 70 0.3 Capital letters A. 8, D A E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 35. 22 ADOPTED VALUES Substance TWA STEL [CAS #] ppttf" mg/m36' ppm"' mg/m34' Iodine [7553-56-2]........... Iodoform [75-47-8].......... Iron oxide fume (FezQj) [1309-37-1], as Fe........ Iron pentacarbonyl [13463-40-6], as Fe...... Iron salts, soluble, as Fe... Isoamyl acetate [123-92-2] Isoamyl alcohol [123-51-3] Isobutyl acetate [110-194)] Isobutyl alcohol [78-83-1]. Isooctyl alcohol [26952-21-6]................ Isophorone [78-59-1]....... Isophorone di isocyanate -- Skin............................ Isopropoxyethano! [109-59-1].................... Isopropyl acetate [108-21-4].................... Isopropyl alcohol [67-63-0] Isopropylamine [75-31-0].. N-lsopropytaniline [643-28-7] -- Skin....... Isopropyl ether [108-20-3]. Isopropyl glycidyl ether [4016-14-2] (IGE)......... Kaolin.............................. Ketene [463-514]............ Lead [7439-92-1], inorg., dusts & fumes, as Pb.... *f Lead aresnate [10102-484], as Pb3(AsCU)2............... Lead chromate [18454-12-1], as Cr...... Limestone [1317-65-3]..... Lindane [58-89-9] -- Skin. Lithium hydride [7580-67-8]................. L.P.G. (Liquified petroleum gas)............................ Magnesite [546-90-0]....... C0.1 0.6 83 0.1 -- 100 100 150 50 50 C5 0.01 25 250 400 5 2 250 50 -- 0.5 _ _ _ -- -- __ 1,000 -- Cl 10 5 0.8 1 525 360 700 150 270 C 25 0.09 105 950 980 12 10 1,050 240 D 0.9 0.15 0.15 0.05, A2 D 0.5 0.025 1,800 D 1 __ 0.2 -- 125 125 187 75 _ -- __ 75 310 500 10 5 310 75 -- 1.5 _ __ _ -- -- -- 1,250 -- __ 20 10 1.6 2 655 450 875 225 _ -- 320 1,185 1,225 24 20 1,320 360 20 3 0.45 (0.45) _ 20 1.5 __ 2,250 20 Capital letters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 35. *1983 Addition. See Notice of Intended Changes. 23 LAM009369 Substance [CAS #] ADOPTED VALUES TWA STEL ppm01 mg/m34' ppm'" mg/m34' Magnesium oxide fume [1309-484].................. Malathion [121-75-5] -- Skii............................. Maleic anhydride [108-31-6].................... 0.25 Manganese [7439-96-5], as Mn Dust & compounds...... Fume........................... -- Manganese cydopentadienyi tricarbonyl [12079-65-1], as, Mn -- Skin............ Manganese tetroxide......... -- Marble/calcium carbonate [1317-65-3]................. Mercury [7439-97-6], as Hg -- Skin Alkyl compounds.......... All forms except alkyl Vapor........................ _ Aryl & inorganic compounds............... _ Mesityl oxide [141-79-7]... 15 Methacrylic acid [79414]. 20 Methane [74-82-8]........... E Methanethiol, see Methyl mercaptan Methomyl [16752-77-5] - Skin............................. -- Methoxychlor [7243-5].... -- 42-Methoxyethanol [109-864]-- Skin......... (25) 42-Methoxyethyi acetate [11049-6] -- Skin....... (25) 4-Methoxyphenol [150-76-5].................... _ Methyl acetate [79-20-9]... 200 Methyl acetylene [74-99-7] 1,000 Methyl acetylene-propadiene mixture (MAPP)........... 1,000 Methyl acrylate [96-33-3] -- Skin......................... 10 Methylacrylonitrile [126-98-7] --Skin....... 1 10 10 1 C5 1-- 0.1 1-- D_ 0.01 0.05 0.1 60 70 -- _ _ 25 -- -- 2.5 10 -- (80) (35) (120) 5 610 1,650 (35) ___ 250 1,250 1,800 1,250 35 32 3 0.3 -- 20 0.03 _ -- 100 -- -- -- (120) (170) _ 760 2,040 2,250 6 Capital letters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru I) see Page 35. tSee Notice of Intended Changes. 24 Substance [CAS #] ADOPTED VALUES TWA STEL ppm" mg/m34' ppm' mg/m34' Methylal [109-87-5].......... 1,000 3,100 Methyl alcohol [67-56-1] (methanol) -- Skin....... 200 260 Methylamine [74-89-5]..... 10 12 Methyl amyl alcohol, see Methyl isobutyl carbinol Methyl n-amyl ketone [11043-0].................... 50 235 N-Methyl aniline [100-61-8] --Skin....... 0.5 2 Methyl bromide [74-83-9] -- Skin......................... 5 20 Methyl n-butyl ketone [591-78-6].................... 5 20 Methyl chloride [74-87-3].. 50 105 Methyl chloroform [71-55-6]..................... 350 1,900 Methyl 2-cyanoacrylate [137-05-3].................... 2 8 Methylcydohexane [108-87-2].................... 400 1,600 Methylcyclohexanol [2563942-3]................ 50 235 o-Methylcydohexanone [583-60-8] --Skin....... 50 230 Methylcydopentadienyl manganese tricarbonyl, [12108-13-3] --Skin, as Mn.......................... 0.2 Methyl demeton [8022-00-2] -- Skin..... _ 0.5 Methylene bisphenyl iso cyanate (MDI) [101-68-8].................... C 0.02 C 0.2 Methylene chloride [75-09-2]..................... 100 350 4,4'-Methylene bis (2-chloroaniline) [101-144] --Skin....... 0.02, A2 0.22, A2 Methylene bis(4-cydo- hexylisocyanate) [5124-30-1]................. C0.01 C0.11 4, 4-Methylene dianiline [101-77-9] --Skin....... 0.1 0.8 1,250 250 -- 100 1 15 _ 100 450 4 500 75 75 _ 500 0.5 3,875 310 -- 465 5 60 205 2,450 16 2,000 350 345 0.6 1.5 1,740 4 Capital letters A, B, D 4 E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 35. *1983 Addition. 25 SC 008160 LAM009370 Substance [CAS #] ADOPTED VALUES TWA STEL ppm11 mg/m34' ppm0' mg/m341 Methyl ethyl ketone (MEK) [78-93-3] ..................... 200 590 Methyl ethyl ketone peroxide [1338-23-4].... C 0.2 C 1.5 Methyl formate [107-31-3]. 100 250 5-Methyl-3-heptanone, see Ethyl amyl ketone Methyl hydrazine [60-34-4] -- Skin........................ C 0.2, C0.35, A2 A2 Methyl iodide [74-88-4] -- Skin............................ 2, A2 10, A2 Methyl isoamyl ketone [110-12-3].................... 50 240 Methyl isobutyl carbinol [105-30-6] -- Sken....... 25 100 Methyl isobutyl ketone [108-10-1].................... 50 205 Methyl isocyanate [624-83-9] --Skin....... 0.02 0.05 Methyl isopropyl ketone [563-80-4].................... 200 705 Methyl mercaptan [74-93-1]..................... 0.5 1 Methyl methacrylate [80-62-6]..................... 100 410 Methyl parathkm [298-00-0] --Skin....... _ 0.2 Methyl propyl ketone [107-87-9].................... 200 700 Methyl silicate [681 -84-5].. 1 6 a-Methyl styrene [98-83-9] 50 240 Mevinphos [7786-34-7] -- Skin.....^...................... 0.01 0.1 Molybdenum [7439-98-7], as Mo Soluble compounds...... Insoluble compounds.... -- 5 10 Monocrotophos [6923-224]................. __ 0.25 Morpholine [110-91-8] -- Skin............................ Naled [300-76-5].............. 20 -- 70 3 Naphthalene [91-20-3]...... 10 50 /3-Naphthylamine [91 -59-8] -- Alb 300 __ 150 5, A2 _ 40 75 _ _ _ 125 __ 250 5 100 0.03 -- _ 30 -- 15 -- 885 __ 375 30, A2 _ 165 300 _ _ ___ 510 0.6 875 30 485 0.3 10 20 _ 105 6 75 Alb Capital letters A, B, 0 & E refer to Appendices: C denotes ceiling Emit. Footnotes (a thru f} see Page 35. 26 ADOPTED VALUES TWA STEL Substance [CAS #] ppm01 mg/m34' ppm" mg/m34' Neon [7440-01-9]............ E -- Nickel carbonyl, as Ni....... 0.05 0.35 Nickel [7440-02-0] Metal........................... 1 Soluble compounds, as Ni................................ 0.1 Nickel carbonyl [13463-39-3], as Ni...... 0.05 0.35 Nickel sulfide roasting, fume & dust, as Ni....... 1, Ala Nicotine [54-11-5] -- Skin. -- 0.5 Nitrapyrin [1929-824]...... -- 10 Nitric acid [7697-37-2]..... 2 5 Nitric oxide [1010243-9].. 25 30 p-Nitraaniline [100-01-6] -- Skin......................... 3 Nitrobenzene -- Skin....... 1 5 tp-Nitrochlorobenzene [100-00-5] --Skin....... (D 4-Nitrodiphenyl [92-93-3].. -- Alb Nitroethane [79-24-3]....... 100 310 Nitrogen dioxide [1010244-0]................ 3 6 Nitrogen trifluoride [7783-54-2]................. 10 30 '^Nitroglycerin (NG) [55-63-0]--Skin......... 0.05 0.5 Nitromethane [75-52-5].... 100 250 1-Nitropropane [108-03-2]. 25 90 t2-Nitropropane [7946-9].. (C 25, (C 90, A2) A2) N-Nitrosodimethylamine [62-75-9] (dimethylnitro- soamhe) --Skm.......... A2 Nitrotoluene [99-08-1] -- Skii............................ 2 11 Nitrotrichloromethane, see Chloropicrin Nonane [111-84-2]........... 200 1,050 Octachloronaphthalene [2234-13-1] --Skin..... _ 0.1 Octane [111-65-9]............ 300 1,450 Oil mist, mineral............... -- S'1 _ -- _ -- -- 4 35 2 _ -- 150 5 15 (0.1) 150 35 __ 250 375 -- -- -- 0.3 _ 1.5 20 . 10 45 _ 10 (2) Alb 465 10 45 (D 375 135 A2 1,300 0.3 1,800 10 Capital letters A, B, D & E refer to Appendices: C denotes ceiling Bmit. Footnotes (a thru f) see Page 35. *1983 Addition. See Notice of Intended Changes. 27 008161 LAM009371 sc 008162 Substance [CAS#] ADOPTED VALUES TWA STEL ppm"' mg/m3*' ppm0' mg/m36' Osmium tetroxide [20816-12-0], as Os..... 0.0002 0.002 0.0006 0.006 Oxalic acid [144-62-7]...... -- 1-- 2 Oxygen difluoride [7783-41-7]................. 0.05 0.1 0.15 0.3 Ozone [10028-15-6]......... 0.1 0.2 0.3 0.6 Paraffin wax fume [8002-74-2]................. -- 2-- 6 Paraquat [1910-42-5], respirable sizes............ -- 0.1 -- -- Parathion [56-38-2] -- Skin............................ -- 0.1 -- 0.3 Particulate polycyclic aromatic hydro-carbons (PPAH), see Coal tar pitch volatiles Pentaborane [19624-22-7]. 0.005 0.01 0.015 0.03 Pentachloronaphthalene [1321-64-8]................. -- 0.5 -- 2 Pentachlorophenol [87-86-5] -- Skin......... Pentaerythritol [115-77-5]. -- -- 0.5 -- D-- 1.5 20 Pentane [109-66-0].......... 600 1,800 750 2,250 2-Pentanone, see Methyl propyl ketone tPerchloroethylene [127-184].................... Perchloromethyl mercaptan [59442-3].................... 50 0.1 335 (-) 0.8 -- (-) -- Perdtloryl fluoride [7616-94-6]................. 3 14 6 28 Phenol [108-95-2] --Skin. 5 19 10 38 Phenothiazine [92-84-2] -- Skin............................ -- 5-- 10 N-Phenyl-beta-naphthyl- amine [135-88-6].......... A2 A2 -- -- p-Phenylene diamine [106-50-3] --Skin....... -- 0.1 -- -- Phenyl ether [101-84-8], vapor........................... 1 72 14 Phenylethylene, see Styrene, monomer Phenyl glycidyl ether (PGE) [122-60-1].................... i 6-- -- {Phenylhydrazine [100-63-0] --Skin....... (5) (20) (10) (45) Capital letters A, 8, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 35. fSee Notice of Intended Changes. 28 Substance _ _ _ _ _ _ _ _ _ ADOPTED VALUES TWA STEL [CAS #] ppm" mg/m31" ppm" mg/m3*' Phenyl mercaptan [108-98-5].................... 0.5 2-- -- Phenylphosphine [638-21-1].................... C0.05 Phorate [298-02-2] -- Skin -- C0.25 0.05 -- -- -- 0.2 Phosdrin, see Mevinphos Phosgene [7544-5].......... Phosphate [3803-51-2]..... 0.1 0.3 0.4 -- 0.4 1 -- 1 Phosphoric acid [7664-38-2]................. -- 1-- 3 Phosphorus [7723-14-0] (yellow)....................... -- 0.1 -- 0.3 Phosphorus oxychloride [1(5026-13-8]................ 0.1 0.6 0.5 3 Phosphorus pentachloride [10026-13-8]................ 0.1 1-- -- Phosphorus pentasulfide [1314-80-3]................. -- 1-- 3 Phosphorus trichloride [7719-12-2]................. 0.2 1.5 0.5 3 Phlhalic anhydride [8544-9]..................... 1 64 24 m-Phthalodinitrile [626-17-5].................... Pidoram [1918-02-1]....... -- -- 5-- 10 -- -- 20 Picric acid [88-89-1] -- Skin............................ Pindone [83-26-1]............. -- -- 0.1 -- 0.1 -- 0.3 0.3 Piperazine dihydrochloride [142-64-3].................... -- 5-- -- 2-Pivalyl-l, 3-indandione, see Pindone Plaster of Paris................ -- D-- 20 Platinum [7440-064] Metal........................... Soluble salts, as Pt....... --1 -- 0.002 -- -- -- -- Polychlorobiphenyls, see Chlorodiphenyls Polytetrafluoroethylene decomposition products. -- B1 -- B1 Potassium hydroxide [1310-58-3]................. -- C2 -- -- Propane [74-98-6]........... E -- -- -- Propane sultone [1120-714]................. A2 A2 -- Capital tetters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 35. 29 LAM009372 sc 008163 Substance[CAS #] ADOPTED VALUES TWA STEL ppm01 mg/m3*' ppm" mg/m**' Propargyl alcohol [107-19-7] -- Skh 1 -Propiolactone [57-57-8]. 0.5, A2 Propionic acid [79-09-4]... 10 Propoxur [114-26-1]......... -- n-Propyl acetate [109-604]................... 200 Propyl alcohol [71-23-8] -- Skin......................... 200 n-Propyl nitrate [627-134] 25 Propylene [115-07-1]....... E Propylene dichloride [78-87-5]..................... 75 'tPropylene glycol dinitrate [6423434] -- Skin..... 0.05 Propylene glycol mono- methyl ether [107-98-2], 100 *Propyleneimine [75-55-8] -- Skin......................... 2, A2 Propylene oxide [75-56-9]. 20 Propyne, see Methyl acetylene Pyrethrum [8003-34-7]..... Pyridine [110-86-1].......... 5 Quinone [106-514].......... 0.1 RDX, see Cydonite Resorcinol [10846-3]...... 10 Rhodium [7440-16-6] Metal........................... $ Soluble salts, as Rh...... Ronnel [299-84-3]........... -- -- Rosin core solder pyrolysis products, as formaldehyde............... Rotenone (commercial) [83-794]..................... Rouge............................. -- Rubber solvent (Naphtha).. 400 Selenium compounds [778249-2], as Se....... Selenium hexafluoride [7783-79-1], as Se....... 0.05 Sesone [136-78-7]........... -- 2 1.5, A2 30 0.5 840 500 105 -- 350 0.3 360 5, A2 50 5 15 0.4 45 1 (0.001) 10 0.1 5 D 1,600 0.2 0.2 10 3 1, A2 15 -- 250 250 40 _ 110 (0.1) 150 6 3, A2 45 2 1,050 625 170 -- 510 (0.6) 540 __ __ 10 10 30 0.3 1 20 90 -- (0.003) ---- 0.3 10 -- 20 ---- -- 20 Capital letters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 35. '1983 Addition. tSee Notice of Intended Changes. 30 Substance[CAS#] ADOPTED VALUES TWA STEL ppm" tng/m^" ppm01 mg/m3*' Silane, see Silicon tetrahydride Silicon [7440-21-3].......... -- D-- Silicon carbide [409-21-2]. -- D-- 'Silicon tetrahydride (Silane) [7803-62-5].............:... 5 7-- Silver [7440-22-4], as Ag Metal........................... Soluble compounds...... -- 0.1 -- 0.01 -- -- Sodium azide [26628-22-8] C0.1 C 0.3 -- Sodium bisulfite [7631-90-5]................. -- 5-- Sodium 2, 4-dichloro-phenoxyethyl sulfate, see Sesone Sodium fluoroacetate [62-74-8] -- Skin......... -- 0.05 -- Sodium hydroxide [1310-73-2].................. -- C2 -- Sodium metabisulfite [7681-574]................. -- 5-- Starch [9005-84-9]........... -- D-- Sttoine [7803-52-3].......... 0.1 0.5 0.3 Stoddard solvent [805241-3]................. 100 525 200 Strychnine [57-24-9]......... -- 0.15 -- Styrene, monomer [10042-5].................... 50 215 100 Subtilisins [1395-21-7] (Proteolytic enzymes as 100% pure crystalline enzyme)........................ Sucrose [57-50-1]............. --co.ooooe"' --D -- -- Sulfotep [3689-24-5] -- Skin............................. -- 0.2 -- Sulfur dioxide [7446-09-5]. 2 55 Sulfur hexafluoride [2551-624].................. 1,000 6,000 1,250 Sulfuric acid [7664-93-9].. -- 1-- Sulfur monochloride [10025-67-9]................ 1 63 Sulfur pentafluoride [5714-22-7].................. 0.025 0.25 0.075 Sulfur tetrafluoride [7783-60-0]................. 0.1 0.4 0.3 20 20 -- -- -- -- -- . 0.15 -- -- 20 1.5 1,050 0.45 425 -- 20 0.6 10 7,500 -- 18 0.75 1 Capital letters A. B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 35. *1983 Addition, m) See Page 38. 31 LAM009373 sc 008164 Substance[CAS#] ADOPTED VALUES TWA STEL ppm" mg/m*1" ppm" mg/m*" Sulfuryl fluoride [2699-79-8]................. 5 20 Systox, see Demeton 2, 4, 5-T [93-76-5]........... -- 10 Tantalum [7440-25-7]...... 5 TEDP, see Sulfotep Tellurium & compounds [13494-80-9], as Te..... --1* 0.1 Tellurium hexafluoride [7783-80-4], asTe....... 0.02 0.2 Temephos [3383-96-8]..... -- 10 TEPP [10749-3]-Skin... 0.004 0.05 Terphenyls [92-944]....... C 0.5 C5 1,1,1,2-Tetrachloro~2, 2- difluoroethane [76-11-9] 500 4,170 1,1, 2, 2-Tetrachloro-1, 2- difluoroethane [76-12-0] 500 4,170 1,1,2, 2-Tetrachloro- ethane [79-34-5] -- Skin 1 7 Tetrachloroethylene, see Perchloroethylene Tetrachloromethane, see Carbon tetrachloride- Tetrachloronaphthalene [1335-88-2]................. -- 2 Tetraethyl lead [78-00-2], as Pb -- Skin............... -- . 0.100'' Tetrahydrofuran [109-99-9] 200 590 Tetramethyl lead [75-74-1], as Ph -- Skin............... -- 0.150 Tetramethyl sucdnonitrile [3333-52-6] -- Skin..... 0.5 3 Tetranitromethane [509-14-8].................... 1 8 Tetrasodium pyrophosphate [7722-88-5]................. 5 Tetryl [47945-8] (2, 4, 6-trinitrophenyl- methylnitramine) -- Skin 1.5 Thallium [7440-28-0] Soluble compounds, as Tl -- Skin..................... -- 0.1 4, 4'-Thiobis(6-tert. butyl- m-cresol) [96-69-5]...... -- 10 Thioglycolic acid [68-11-1] 1 5 10 -- -- -- -- 0.01 -- 625 625 5 -- -- 250 -- 2 -- -- -- 40 20 10 -- _ 20 0.2 -- 5,210 5,210 35 4 0.3 735 0.5 9 3.0 -- 20 -- Capital letters A, B, 0 4 E refer to Appendices; C denotes ceiling limit, footnotes (a thru f) see Page 35. 32 ADOPTED VALUES Substance TWA [CAS #] ppm"' mg/m3 STEL ppm" mg/m*1" Thiram [137-26-8]........... -- 5 Tin [7440-31-5] Metal........................... 2 Oxide & inorganic compounds, except Sn04, as Sn................... _ 2 Organic compounds, as Sn -- Skin.................... _ 0.1 Titanium dioxide [13463-67-7], as Ti...... -- o-Tofidine [119-93-7] -- Skin............................ Toluene [108-88-3] (toluol) -- Skin......................... ' Toluene-2,4-diisocyanate (TDI) [584-84-9]........... A2 100 0.005 A2 375 0.04 to-Toluidine [95-534] -- Skin............................ (2) Toxaphene, see Chlorinated camphene 0) Tributyl phosphate [126-73-8].................... 0.2 2.5 Trichloroacetic acid [76-03-9]..................... 1 5 1, 2, 4-Trichlorobenzene [120-82-1].................... C5 C40 1,1,1-Trichloroethane, see Methyl chloroform 1,1, 2-Trichloroelhane [79-00-5] -- Skin......... 10 45 ^Trichloroethylene [79-01-6] 50 270 Trichlorofluoromethane [75-694]..................... C 1,000 C 5,600 Trichtoromethane, see Chloroform Trichloronaphthalene [1321-65-9]................. -- Trichloronitromethane, see Chloropicnn 5 1,2, 3-Trichloropropane [96-184]..................... 50 300 1,1, 2-Trichloro-1, 2, 2trifluoroethane [76-13-1] 1,000 7,600 Tricydohexyttin hydroxide, see Cyhexatin 'Triethylamine [12144-8]... 10 40 Trifluorobromomethane [75-63-8]..................... 1,000 6,100 -- _ _ -- -- 150 0.02 -- 0.4 -- 20 (150) -- -- 75 1,250 15 1,200 10 4 4 0.2 20 -- 560 0.15 -- 5 " -- 90 (805) -- 10 450 9,500 60 7,300 Capital letters A, B, D 4 E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 35. *1983 Addition. See Notice of Intended Changes. 33 LAM009374 Substance[CAS#] ADOPTED VALUES TWA STEL ppm"1 mg/m1*1 ppm01 mg/np'" Trimellitic anhydride [552-30-7].................... 'Trimelhylamine [75-50-3].. Trimethyl benzene 0.005 10 0.04 24 [25551-13-7]................ 25 125 Trimethyl phosphite [121-45-9].................... 2 2, 4, 6-Trinitrophenol, see Picric acid 10 2,4, 6-Trinitrophenyl-methylnitramine, see Tetiyl 2,4, 6-Trinitrotoluene (TNT) [118-96-7] -- Skat............................. -- 0.5 Triorthocresyl phosphate [78-30-8]..................... ___ 0.1 Triphenyl amine [603-34-9] -- 5 Triphenyl phosphate [115-86-6].................... Tungsten [7440-33-7], as W Insoluble compounds.... Soluble compounds...... Turpentine [8006-64-2]..... Uranium (natural) __ __ 100 3 5 1 560 [7440-61-1], Soluble & In- soluble compounds, as U Valeraldehyde [110-62-3]... Vanadium, as V2 65 _ 50 0.2 175 [1314-62-1], respirable dust & fume................. Vegetable oil mists............ Vinyl acetate [108-05-4]..... Vinyl benzene, see Styrene _ 0.05 __ D 10 30 Vinyl bromide [593-60-2]... 5, A2 Vinyl chloride [75-01-4]..... 5, Ala Vinyl cyanide, see Acrylonitrile Vinyl cyctohexene dioxide 20, A2 10, Ala [106-87-6]................... 10, A2 60, A2 TVinylidene chloride [75-364].................... Vinyl toluene [25013-154]. VM &P Naphtha (10) 50 (40) 240 [8030-306]................. Warfarin [8161-2]............ 300 1,350 -- 0.1 15 35 5 -- _ -- -- -- 150 _ _ _ 20 _ -- -- (20) 100 400 Capital letters A, B, 0 & E refer to Appendices; C denotes ceiling limit. Footnotes (a ttmi f) see Page 35. *1983 Addition. tSee Notice of Intended Changes. 36 170 25 3 0.3 6 10 3 840 0.6 60 _ -- -- (80) 485 1,800 0.3 34 Substance [CAS #] ADOPTED VALUES TWA STEL ppm"' mg/m36' ppm"' mg/m361 Welding fumes (NOCt)...... Wood dust (certain hard woods as beech & oak).. Softwood.................... Xylene [1330-20-7] (0-, m-, p-isomers).................... m-Xylenea, a'-diamine [1477-55-0] -- Skin..... Xylidine [1300-73-8] -- Skin........................... Yttrium [7440-65-5]......... Zinc chloride fume [7646-85-7]................. Zinc chromate [13530-65-9], as Cr...... Zinc oxide [1314-13-2] Fume.......................... Dust........................... Zinc stearate [557-05-1].... Zirconium compounds [7440-67-2], as Zr........ -- 5, B2 -- 5* - -- 100 435 150 -- C0.1 -- 2 10 -- -- 0.05, A2 --5 --D --D --5 -- -- -- -- - 10 655 3 2 10 20 10 Capital letters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 35. tNOC = Not otherwise classified. a) Parts of vapor or gas per million parts of contami nated air by volume at 25C and 760 mm Hg pres sure. b) Approximate milligrams of substance per cubic meter of air. d) < 7 /zm in diameter. e) As sampled by method that does not collect vapor. f) For control of general room air, biologic monitoring is essential for personnel control. Radioactivity: The Committee accepts the philosophy and recommendations of the National Council on Ra diation Protection and Measurements (NCRP) for the ionizing radiation TLV. The NCRP is charted by Con gress to, in part, collect, analyze, develop and dissem inate information and recommendations about pro tection against radiation and about radiation measurements, quantities and units, including devel- 35 SC 008165 LAM009375 opment of basic concepts in these areas. NCRP Re port No. 39 (reference 1) provides basic philosophy and concepts leading to protection criteria estab lished in the same report. Other NCRP reports ad dress specific areas of radiation protection and, col lectively, provide an excellent basis for establishing a sound program for radiation control. The Committee recommends the listed references as substantative documentation of a sound basis for ionizing radiation protection. The Committee also strongly recommends that all exposures to ionizing radiations be kept low as reasonably achievable within the stated guidance. References: 1. Basic Radiation Protection Criteria. NCRP Report No. 39, issued January 15,1971. 2. Maximum Permissible Body Burdens and Maxi mum Permissible Concentrations of Radionuclides in Air and in Water for Occupational Exposure. US Department of Commerce, National Bureau of Standards Handbook 69, issued June 5, 1959, with Addendum 1 issued August 1963. Available as NCRP Report No. 22. The above documents, as well as information on nu merous other NCRP Reports addressing specific sub jects in ionizing radiation protection are available from: NCRP Publications, PO Box 30175, Washing ton, DC 20014. Substance SIUCA, S/02 MINERAL DUSTS TLV Crystalline TQuartz [14808-60-7] JCristobalite.. [14464-46-1] TLV in mppcf1": 300'11 % quartz + 10 TLV for respirable dust mg/m3: 10 mg/m3" in % Respirable quartz + 2 TLV for "total dust," respirable and nonrespirable: 30 mg/m3 % quartz +3 .Use one-half the value calculated from the count or mass formulae for quartz. tSee Notice of Intended Changes. 36 tTridymite........ .....Use one-half the value calculated [15468-32-3] from formulae for quartz. ^Silica, fused [60676-86-0].......... Use quartz formulae. ^Tripoli.....................Use respirable1" mass quartz for- [1317-95-9] mula ptmorphous [7631-86-9]............................ (20 mppcf1") SILICATES (< 1% quartz) Asbestos" Amosite...................... 0.5 fiber/cc > 5 p.m in [12172-73-5] length,Ala Chrysotile.................... 2 fibers/cc > 5 /j.m in [12001-29-5] length,Ala Crocidolite.................. 0.2 fiber/cc > 5 pm in [12001-28-4] length,Ala Other forms................ 2 fibers/cc > 5 ^m in length, Ala ^Graphite (natural) [7782-42-5]................. 15mppcf *Mica [12001-26-2].......... 20mppcf Mineral wool fiber.......... 10 mg/m3 tPerlite............................... 30mppcf. ^Portland Cement............. 30 mppcf ^Soapstone........................ 20mppcf *Talc (containing no asbes tos fibers) [14807-96-6].............. 2 mg/m3, Respirable dust JTaic (fibrous), (use Asbestos limit.) COAL DUST 2 mg/m3 (respirable dust fraction < 5% quartz). $(lf > 5% quartz, use respirable mass formula.) NUISANCE PARTICULATES (see Appendix D) $(30 mppcf) or 10 mg/m3" of total dust < 1% quartz, or, 5 mg/m3 respirable dust. Conversion factors: mppcf x 35.3 = Million particles per cubic meter = particles per cc g) Millions of particles per cubic foot of air, based on impinger samples counted by light-field technics. $See Notice of intended Changes. `1983 Addition. 37 sc 008166 LAM009376 h) The percentage of quartz in the formula is the amount determined from airborne samples, except in those instances in which other methods have been shown to be applicable. i) Both concentration and percent quartz for the appli cation of this limit are to be determined from the fraction passing a size-selector with the following racteristics: Aerodynamic Diameter Q*m) (unit density sphere) <2 2.5 3.5 5.0 10 % passing selector 90 75 50 25 0 Tj) containing < 1% quartz; (if quartz content > 1%, use formulae for quartz.) k) Lint-free dust as measured by the vertical elutriator, cotton-dust sampler described in tile Transactions of the National Conference on Cotton Dust, p. 33 by J. R. Lynch, (May 2, 1970). l) As determined by the membrane filter method at 400-450X magnification (4 mm objective) phase contrast illumination. m) Based on "high volume" sampling. n) "Respirable" dust as defined by the British Medical Research Council Criteria,111 and as sampled by a device producing equivalent results.12' (1) Hatch, T. E. and Gross; Pulmonary Deposition and Retention of Inhaled Aerosols, p. 149. Aca demic Press, New York, (1964). (2) AIHA Aerosol Technology Committee: Interim Guide for Respirable Mass Sampling. Am. Ind. Hyg. Assoc. J. 370:133 (1970). NOTICE OF INTENDED CHANGES (for 1983-84) These substances, with their corresponding val ues. comprise those for which either a limit has been proposed for the first time, or for which a change in the "Adopted" listing has been proposed. In both cases, the proposed limits should be considered trial tSee Notice of Intended Changes. 38 limits that will remain in the listing for a period of at least two years. If, after two years no evidence comes to light that questions the appropriateness of the val ues herein, the values will be reconsidered for the "Adopted" list. Documentation is available for each of these substances. Substance [CAS #1 ppm0' mg/m34' ppm"' mg/m34' Acrylonitrile [107-13-1] -- Skin............................ 2, A2 4.5, A2 tl, 3-Butadiene [106-99-0]. A2 A2 -- -- Cobalt metal, dust & fume [7440-48-4], as Co....... __ 0.05 0.1 Enflurane [13838-16-9]..... 75 575 -- -- 2-Ethoxyethanol [110-80-5] -- Skin......................... 5 19 _ _ 2-Ethoxyethyl acetate [111-15-9] --Skin....... 5 27 _ __ Ethyleneglycol [107-21-1], particulate DELETE, see Appendix G tEthylene glycol dinitrate [628-96-6] --Skin....... 0.05 0.3 _ Ethylene oxide [75-21-8]... 1, A2 2, A2 -- -- Fenamiphos [22224-92-6] -- Skin........................ _0.1 _ tFcrmaldehyde [50-00-0].... Grain dust....................... Halothane [151-67-7]....... 1, A2 -- 50 1.5, A2 4 400 2, A2 -- -- 3, A2 -- -- Head arsenate [10102-48-4], as Pb3(AsQ4)2............... 0.15 2-Melhoxyethanol [109-86-4] --Skin....... 5 16 __ __ 2-Methoxyelhyl acetate [110-49-6] -- Skin Metribuzin [21087-64-9]... 5 -- 24 _ 5-- _ -- p-Nitrochlorobenzene [100-00-5] --Skin....... 0.5 3 tNitroglycerii [55-63-0] -- Skin............................ 0.05 0.5 2-Nitropropane [79-46-9].. 10, A2 35, A2 20, A2 70, A2 Perchloroethylene [127-18-4].................... 50 335 200 1,340 Persulfates, alkali metal, as S208............................ -- 2-- -- Capital letters A, B, D & E refer to Appendices: C denotes ceiling limit. f1983 Revision or Addition. 39 008A67 SC LAM009377 sc 008168 Substance TWA STEL [CAS #] ppm"' mg/m*41 ppm"' mg/m3" Phenylhydrazine [100-63-0] - Skin....... tPropylene glycol dinitrate [6423-43-4] - Skin..... Rhodium, Insoluble compounds, as Rh....... Soluble compounds, as Rh............................... Sulprofos [3540043-2].... o-Toluidine [95-534] -- Skin............................. Trichloroelhylene [79-01-6] Vinylidene chloride [75-3541..................... 5, A2 0.05 -- -- -- 2, A2 50 5 20, A2 10, A2 0.3 - 1- 0.01 1 9, A2 270 200 20 20 45, A2 1,080 80 Capital letters A, B, D & E refer to Appendices: C denotes ceiling limit. 11983 Revision or Addition. NOTICE OF INTENDED CHANGES MINERAL DUSTS Substance SILICA, SiOa TLV Crystalline Quartz.................... 0.1 mg/m3, Respirable dust [14808-60-7] 0.3 mg/m3, Total dust Cristobalite........... 0.05 mg/m3, Respirable dust [1446446-1] 0.15 mg/m3, Total dust Tridymite.............. 0.05 mg/m3, Respirable dust [15468-32-3] 0.15 mg/m3, Total dust Silica, fused........... Use quartz values. [60676-86-0] Tripoli.....................Use respirable quartz value. [1317-95-9] Silica, amorphous.. 5 mg/m3, Respirable dust [7631-86-9] 10 mg/m3, Total dust SIUCATES (< 1% quartz) Oiatomaceous earth 5 mg/m3, Respirable dust (uncalcined) 10 mg/m3, Total dust [60676-86-0] Graphite (natural)...2.5 mg/m3, Respirable dust [778242-5] 5 mg/m3, Total dust 40 Mica [12001-26-2] .3 mg/m3, Respirable dust 6 mg/m3, Total dust Perlite..................... 5 mg/m3. Respirable dust 10 mg/m3, Total dust Portland Cement.... 5 mg/m3, Respirable dust 10 mg/m3, Total dust Precipitated silica 5 mg/m3, Respirable dust and silica gel..... 10 mg/m3, Total dust Soapstone............. 3 mg/m3, Respirable dust 6 mg/m3, Total dust Talc (containing Use asbestos TLV. However, asbestos fibers)..should not exceed 2 mg/m3 respirable dust. COAL DUST If > 5% quartz, use respirable quartz value. Generic Listing All mppcf values for mineral dusts will be eliminated in favor of equivalent respirable mass or total mass values, i.e., Appendix F. Footnote j) Containing < 1% quartz; if quartz content > 1%, use quartz values. APPENDIX A Carcinogens The Committee lists below those substances in in dustrial use that have proven carcinogenic in man, or have induced cancer in animals under appropriate ex perimental conditions. Present listing of those sub stances carcinogenic for man takes two forms: Those for which a TLV has been assigned (la) and those for which environmental conditions have not been suffi ciently defined to assign a TLV (lb). Ala. Human Carcinogens. Substances, or substances associated with industrial processes, recog nized to have carcinogenic or cocarcinogenic potential, with an assigned TLV: TLV ** Acrylonitrile -- Skin Asbestos Amosite............... Chrysotile........... Crocidolite.......... Other forms........ 2 ppm 0.5 fiber > 5|um/cc 2 fibers > 5jzm/cc 0.2 fiber > 5nm/cc 2 fibers > 5/im/cc "See Notice of Intended Changes. ' 41 LAM009378 bis (Chloromethyl) ether Chromite ore processing (chromate)............... Chromium (VI), certain water insoluble compounds............... Coal tar pitch volatiles.. Nickel sulfide roasting, fume & dust.............. Vinyl chloride............... 0.001 ppm 0.05 mg/m3, as Cr 0.05 mg/m3, as Cr 0.2 mg/m3, as benzene solubles 1.0 mg/m3, as Ni 5 ppm Alb. Human Carcinogens. Substances, or sub stances associated with industrial processes, recognized to have carcinogenic potential with out an assigned TLV: 4-Aminodiphenyl (p-Xenylamine) -- Skin Benzidine -- Skin /3-Naphthylamine 4-Nitrodiphenyl For the substances in 1b, no exposure or con tact by any route -- respiratory, skin or oral, as detected by the most sensitive methods -- shall be permitted. The worker should be properly equipped to insure virtually no contact with the carcinogen. A2. Industrial Substances Suspect of Carcinogenic Potential for MAN. Chemical substances or sub stances associated with industrial processes, which are suspect of inducing cancer, based on either (1) limited epidemiologic evidence, exclu sive of clinical reports of single cases, or (2) demonstration of carcinogenesis in one or more animal species by appropriate methods. Acrylonitrile -- Skin Amitrol Antimony trioxide production' Arsenic trioxide production Benzene Benzo(a)pyrene Beryllium 2 ppm 10 ppm 2.0Aig/m3 'Cigarette smoking can enhance the incidence of respiratory cancers from this or others- of these substances or processes. 42 11,3-Butadiene -- Cadmium oxide production -- Carbon tetrachloride -- Skin 5 ppm Chloroform 10 ppm $ Chloromethyl methyl ether -- Chromates of lead and zinc, as Cr 0.05 mg/m3 Chrysene -- 3, 3'-Dichlorobenzidine -- Skin -- Dimethylcarbamyl chloride -- 1,1-Dimethyl hydrazine -- Skin 0.5 ppm Dimethyl sulfate -- Skin Ethylene dibromide -- Skin 0.1 ppm -- Ethylene oxide 1 ppm t Formaldehyde 1 ppm Hexachlorobutadiene 0.02 ppm Hexamethyl phosphoramide -- Skin -- Hydrazine -- Skin 0.1 ppm 4, 4'-Methylene bis (2-chloroaniline) -- Skin 0.02 ppm Methyl hydrazine -- Skin C 0.2 ppm Methyl iodide -- Skin 2 ppm 2-Nitropropane 10 ppm N-Nitrosodimethylamine -- Skin -- N-Phenyl-beta-naphthylamine -- Phenylhyd razine -- Skin 5 ppm Propane sultone -- beta-Propiolactone 0.5 ppm JPropyleneimine -- Skin 2 ppm o-Tolidine -- o-Toluidine -- Skin 2 ppm Vinyl bromide 5 ppm Vinyl cyclohexene dioxide 10 ppm For the above, worker exposure by all routes should be carefully controlled to levels consis tent with the animal and human experience data (see Documentation), including those sub stances with a listed TLV. $1983 Addition, $1983 Adoption. 43 SC 008169 LAM009379 sc 008170 THE COMMITTEE GUIDELINES FOR CLASSIFICATION OF EXPERIMENTAL ANIMAL CARCINOGENS The following guidelines are offered in the pres ent state of knowledge as an aid in classifying substances in the occupational environment found to be carcinogenic in experimental ani mals. A need was felt by the Threshold Limits Committee for such a classification in order to take the first step in developing an appropriate TLV for occupational exposure. Determination of Approximate Threshold of Re sponse Requirement. In order to determine in which category to classify an experimental car cinogen for the purpose of assigning an indus trial air limit (TLV), an approximate threshold of neoplastic response must be determined. Be cause of practical experimental difficulties, a precisely defined threshold cannot be attained. For the purposes of standard-setting, this is of little moment, as an appropriate risk, or safety, factor can be applied to the approximate thresh old, the magnitude of which is dependent on the degree of potency of the carcinogenic re sponse. .. To obtain the best 'practical' threshold of neo plastic response, dosage decrements should be less than logarithmic. This becomes particularly important at levels greater than 10 ppm (or cor responding mg/m3). Accordingly, after a rangefinding determination has been made by lo garithmic decreases, two additional dosage levels are required within the levels of "effect" and "no effect" to approximate the true thresh old of neoplastic response. The second step should attempt to establish a metabolic relationship between animal and man for the particular substance found carcinogenic in animals. If the metabolic pathways are found comparable, the substance should be classed highly suspect as a carcinogen for man. If no such relation is found, the substance should re main listed as an experimental animal carcino gen until evidence to the contrary is found. Proposed Classification of Experimental Animal Carcinogens. Substances occurring in the occu pational environment found carcinogenic for animals may be grouped into three classes, those of high, intermediate and low potency. In evaluating the incidence of animal cancers, sig- 44 nificant incidence of cancer is defined as a neo plastic response which represents, in the judg ment of the Committee, a significant excess of cancers above that occurring in negative con trols. EXCEPTIONS: No substance is to be considered an occupational carcinogen of any practical sig nificance which reacts by the respiratory route at or above 1000 mg/m3 for the mouse, 2000 mg/m3 for the rat; by the dermal route, at or above 1500 mg/kg for the mouse, 3000 mg/kg for the rat; by the gastrointestinal route at or above 500 mg/kg/d for a lifetime, equivalent to about 100 g T.D. for the rat, 10 g T.D. for the mouse. These dosage limitations exclude such sub stances as dioxane and trichlorethylene from consideration as carcinogens. Examples: Dioxane -- rats, hepatocellular and nasal tumors from 1015 mg/kg/d, oral Trichloroethylene -- female mice, tumors (30/98 @ 900 mg/kg/d), oral A. Industrial Substances of High Carcinogenic Po tency in Experimental Animals. 1. A substance to qualify as a carcinogen of high potency must fulfill one of the three fol lowing conditions in two animal species: la. Respiratory. Elicit cancer from (1) dos ages below 1 mg/m3 (or equivalent ppm) via the respiratory tract in 6- 7-hour daily repeated inhalation exposures through out lifetime; or (2) from a single intratracheally administered dose not exceeding 1 mg of particulate, or liquid, per 100 ml or less of animal minute respiratory vol ume; Examples: bis-Chloromethyl ether, malign ant tumors, rats, @ 0.47 mg/m3 (0.1 ppm) in 2 years; Hexamethyl phosphoramide, nasal squamous cell carcino ma, rats, @ 0.05 ppm, in 13 months OR 45 LAM009380 sc 008171 lb. Dermal. Elicit cancer within 20 weeks by skin-painting, twice weekly at 2 mg/kg body weight or less per application for a total dose equal to or less than 1.5 mg, in a biologically inert vehicle; Examples; 7, 12-Dimethylbenz(a)anthra cene -- skin tumors @ 0.120.8 mg T.D. in four weeks Benzo(a)pyrene, mice 12 p.g, 3X/wk for 18 mos. T.D. 2.6 mg, 90.9% skin tumors OR lc. Gastrointestinal. Elicit cancer by daily in take via the gastrointestinal tract, within six months, with a six-month holding period, at a dosage below 1 mg/kg body weight per day; total dose, rat, S 50 mg; mouse, 3.5 mg; Examples: 7, 12-Dimethylbenz(a)anthracene -- mammary tumors from 10 mg IX 3-Methylcholanthrene -- Tumors @ 3 sites from 8 mg in 89 weeks Benzo(a)pyrene, mice, 3.9% leukemias, from 30 mg T.D. 198 days 2. Elicit cancer by all three routes in at least two animal species at dose levels prescribed for high or intermediate potency. B. Industrial Substances of Intermediate Carcinogenic Potency in Experimental Animals. To qualify as a carcinogen of intermediate po tency, a substance should elicit cancer in two animal species at dosages intermediate be tween those described in A and C by two routes of administration. Example; Carbamic 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.D. Gastrointestinal, various type tumors, rats, 60 weeks, 110-930 mg T.D. "46 C. Industrial Substances of Low Carcinogenic Potency in Experimental Animals. To qualify as a carcinogen of low potency, a substance should elicit cancer in one animal species by any one of three routes of adminis tration at the following prescribed dosages and conditions; la. Respiratory. Elicit cancer from (1) dosages I greater than 10 mg/m3 (or equivalent ppm) n via the respiratory tract in 6- 7-hour, daily J repeated inhalation exposures, for 12 months' exposure and 12 months' observa tion period; or (2) from intratracheally ad ministered dosages totaling more than 10 mg of particulate or liquid per 100 ml or more of animal minute respiratory volume; Examples: Beryl (beryllium aluminum silicate) malig. lung tumors, rats, @ l'5 mg/m3@ 17 months Benzidine, var. tumors, rats, 10-20 mg/m3@ > 13 mos. OR lb. Dermal. Elicit cancer by skin-painting of mice in twice weekly dosages of > 10 mg/kg body weight in a biologically inert vehicle for at least 75 weeks, i.e., 1.5g T.D. Examples: Shale tar, mouse, 0.1 ml x 50 = 5g T.D. 59/60 skin tumors Arsenic trioxide, man, dose un known, but estimated to be high lc. Gastrointestinal. Elicit cancer from daily oral dosages of 50 mg/kg/day or greater during the lifetime of the animal. APPENDIX B SUBSTANCES OF VARIABLE COMPOSITION j B1 Polytetralluoroethylene' decomposition products. Thermal decomposition of the fluorocarbon chain in air leads to the formation of oxidized products T containing carbon, fluorine and oxygen. Because 1 these products decompose in part by hydrolysis in alkaline solution, they can be quantitatively de termined in air as fluoride to provide an index of exposure. No TLV is recommended pending de- 'Trade Names: Algoflon, Ruon, Halon, Teflon, Tetran. 47 LAM009381 termination of the toxicity of the products, but air concentrations should be minimal. B2 Welding Fumes -- Total Particulate (NOC)t TLV, Smglm3 Welding fumes cannot be classified simply. The composition and quantity of both are dependent on the alloy being welded and the process and elec trodes used. Reliable analysis of fumes cannot be made without considering the nature of the welding process and system being examined; reactive metals and alloys such as aluminum and titanium are arcwelded in a protective, inert atmosphere such as argon. These arcs create relatively little fume, but an intense radiation which can produce ozone. Similar processes are used to arc-weld steels, also creating a relatively low level of fumes. Ferrous alloys also are arc-welded in oxidizing environments which generate considerable fume, and can produce carbon monox ide instead of ozone. Such fumes generally are com posed of discreet particles of amorphous slags con taining iron, manganese, silicon and other metallic constituents depending on the alloy system involved. Chromium and nickel compounds are found in fumes when stainless steels are arc-welded. Some coated and flux-cored electrodes are formulated with fluorides and the fumes associated with them can contain significantly more fluorides than oxides. Be cause of the above factors, arc-welding fumes fre quently must be tested for individual constituents which are likely to be present to determine whether specific TLV's are exceeded. Conclusions based on total fume concentration are generally adequate if no toxic elements are present in welding rod, metal, or metal coating and conditions are not conducive to the formation of toxic gases. Most welding, even with primitive ventilation, does not produce exposures inside the welding helmet above 5 mg/m3. That which does, should be con trolled. APPENDIX C MIXTURES C.1 THRESHOLD LIMIT VALUES FOR MIXTURES When two or more hazardous substances, which act upon the same organ system, are present, their tNot otherwise classified (NOC). 48 combined effect, rather than that of either individual ly, should be given primary consideration. In the ab sence of information to the contrary, the effects of the different hazards should be considered as additive. That is, if the sum of the following fractions, Ci C2 _C,, Ti T2 ' ' ' T,, exceeds unity, then the threshold limit of the mixture should be considered as being exceeded. Ci indi cates the observed atmospheric concentration, and Ti the corresponding threshold limit (See Example lA.a. and 1A.c.). Exceptions to the above rule may be made when there is a good reason to believe that the chief effects of the different harmful substances are not in fact ad ditive, but independent as when purely local effects on different 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 ^yL + or + etc.^ itself has a value exceeding unity (See Example 1A.c.). Synergistic action or potentiation may occur with some combinations of atmospheric contaminants. Such cases at present must be determined individual ly. Potentiating or synergistic agents are not neces sarily harmful by themselves. Potentiating effects of exposure to such agents by routes other than that of inhalation is also possible, e.g. imbibed alcohol and inhaled narcotic (trichloroethylene). Potentiation is characteristically exhibited at high concentrations, less probably at low. When a given operation or process characteristi cally emits a number of harmful dusts, fumes, vapors or gases, it will frequently be only feasible to attempt to evaluate the hazard by measurement of a single substance. In such cases, the threshold limit used for this substance should be reduced by a suitable factor, the magnitude of which will depend on the number, toxicity and relative quantity of the other contamin ants ordinarily present. Examples of processes which are typically asso ciated with two or more harmful atmospheric conta minants are welding, automobile repair, blasting, painting, lacquering, certain foundry operations, die sel exhausts, etc. 49 SC 008172 LAM009382 C.1A Examples of THRESHOLD LIMIT VALUES FOR MIXTURES The following formulae apply only when the com ponents in a mixture have similar toxicologic effects; they should not be used for mixtures with widely dif fering reactivities, e.g. hydrogen cyanide & sulfur dioxide. In such case the formula for Independent Ef fects (lA.c.) should be used. lA.a. General case, where air is analyzed for each component: a. Additive effects. (Note: It is essential that the atmosphere be analyzed both qualitatively and quantitatively for each component pres ent, in order to evaluate compliance or noncompliance with this calculated TLV.) Ci_ _fe + Ti Ta . =1 Example No. lA.a.: Air contains 400 ppm of acetone (TLV = 750 ppm) 150 ppm of secbutyl acetate (TLV = 200 ppm) and 100 ppm of methyl ethyl ke tone (TLV = 200 ppm) Atmospheric concentration of mix ture = 400 + 150 + 100 = 650 ppm of mixture 400 150 100 750 200 + 200 = 0.53 + 0.75 + 0.5 = 1.78 Threshold Limit is exceeded. 1A.b. Special case when the source of contaminant is a liquid mixture and the atmospheric composi tion is assumed to be similar to that of the orig inal material; e.g. on a time-weighted average exposure basis, all of the liquid (solvent) mix ture eventually evaporates. Additive effects (approximate solution) 1. The percent composition (by weight) of the liquid mixture is known, the TLVs of the constituents must be listed in mg/m3. (Note: In order to evaluate compliance with this TLV, field sampling instruments should be calibrated, in the laboratory, for response to this specific quantitative and qualitative 50 air-vapor mixture, and also to fractional concentrations of this mixture; e.g., 112 the TLV; 1110 the TLV; 2 x the TLV; 10 x the TLV; etc.) TLV of mixture = 1 la . ffi , fc . fn TLV,, TLV, TLVC ' ' TC\/7 Example No. 1 A.b.: Liquid contains (by weight) 50% heptane: TLV = 400 ppm or 1600 mg/m3 1 mg/m3 = 0.25 ppm 30% methyl chloroform: TLV = 350 ppm or 1900 mg/m3 1 mg/m3 s o/18 ppm 20% perchloroethylene: TLV = 50 ppm or 335 mg/m3 1 mg/m3 s 0.15 ppm TLV of Mixture =-^-- 1600 + 1900 + 335 1 0.00031 + 0.00016 + 0.0006 1 = 935 mg/m3 0.00107 of this mixture 50% or (935) (0.5) = 468 mg/m3 is heptane 30% or (935) (0.3) = 281 mg/m3 is methyl chloroform 20% or (935) (0.2) = 187 mg/m3 is perchloroethylene These values can be converted to ppm as follows: heptane: 468 mg/m3 x 0.25 = 117 ppm methyl chloroform: 281 mg/m3 x 0.18 =51 ppm perchloroethylene: 187 mg/m3 x 0,15 = 29 ppm TLV of mixture = 117 + 51 + 29 = 197 ppm, or 935 mg/m3 lA.c. Independent effects. Air contains 0.15 mg/m3 of lead (TLV, 0,15) and 0.7 mg/m3 of sulfuric acid (TLV, 1). Threshold limit is not exceeded. 51. 008173 LAM009383 SC 008174 IB. TLV for Mixtures of Mineral Dusts. For mixtures of biologically active mineral dusts the general formula for mixtures given in lA.b. may be used. APPENDIX D Some Nuisance Particulates0' $TLV, (30 mppcf) or 10 mg/m3 of total dust < 1% quartz, or, 5 mg/m3 respirable dust a-Alumina (AI2O3) Calcium caitonate Calcium silicate Cellulose (paper fiber) Emery Glycerin Mist Graphite (synthetic) Gypsum Kaolin Limestone Magnesite Marble Mineral Wool Fiber Pentaerythritol Plaster of Paris Portland Cement Rouge Silicon Silicon Carbide Starch Sucrose Titanium Dioxide Vegetable oil mists (except castor, cashew nut, or similar irritant oils) Zinc Stearate Zinc oxide dust 0) When toxic impurities are not present, e.g. quartz < 1%. Acetylene Argon Ethane Ethylene APPENDIX E Some Simple Asphyxiants"' Helium Hydrogen Methane Neon Propane Propylene p) As defined on pg. 6. tSee Notice of Intended Changes. 52 ^APPENDIX F Conversion of mppcf to Mass Concentration Calculations for Conversion of Particle Count Con centration (by Standard Light Field -- Midget Impinger Techniques), in mppcf, to Respirable Mass Concentration (by Respirable Sampler) in mg/m3.11' 1. In 1967, Jacobsen and Tomb,11' derived an em pirical relationship of 5.6 mppcf to 1 milligram of respirable dust per cubic meter of air, based on 23 sets of samples, mostly coal dust. Studies on conversion factors have been undertaken and preliminary evidence suggests that the aptplication of any single conversion factor may not be adequate for use in risk assessments, epidemiology studies, or setting TLVs. The following calculation results in an equivalence of 6.37 mppcf to 1 mg/m3 of respir able dust. Thus, an approximate ratio of 6 mppcf to 1 mg/m3 of respirable dust is suggest ed for conversion of TLVs from a count to a mass basis when the density and mass median diameter have not been determined. 2. Basic assumptions: a) Average density for silica containing dusts = 2.5 g/cm3 (2500 mg/cm3). Pulmonary sig nificant dust densities may vary from 1.2 g/cm3 for coal dust to 3.1 g/cm3 for Portland Cement. Silica densities vary from 2.2 (amor phous) to 2.3 (cristobalite and tridymite) to 2.5 (alpha-quartz.) gms per cm3. b) The mass median diameter (mmd) of parti cles collected in midget impinger samplers and counted by the standard light field tech nique, and collected in a respirable sampler is approximately 1.5 /xm or 1.5 x 10-* cm. This assumption is, of course, quite arbitrary since the mmd of ail dust clouds is quite variable, depending on many independent parameters, such as source of dust, age of dust cloud, meteorological conditions, pro cesses and equipment changes, etc. If the density and the mass median diameter of the dust particles are known, the nomograph in Figure 1 can be used to convert dust count concentrations (mppcf) to respirable mass concentrations (mg/m3). $See Notice of Intended Changes. 53 UM009384 3. Calculation: a) vol. per particle: 4/3 v r3; r = 0.75 x 10~4 cm = 4/3* 77* (0.75 x 10-4)3 = 1.77 x 10~12 cm3 b) wt. per particle = vol. x density = 1.77 x 10~12 cm3 x 2.5 x 103 mg/cm3 = 4.425 x io~9 mg/particle c) 1 particle/ft.3 = 35.3 part./m3 (since 35.5 cu ft = 1 cu m.) 10s part./ft3 = mppcf = 35.3 x 10s part./m3 wt. of 1 mppcf = 35.5 x 10 part./m3 x 4.425 x 10~9 mg/part. 1 mppcf = 0.157 mg/m3 or 6.37 mppcf = 1 mg/m3 or approximately 6 mg/m3. mpccf = 1 Reference 1. Jacobson, M. and T. F. Tomb: Relationship Between Gravimetric Re spirable Dust Concentration and Midget Impinger Number Concentra tion. Am. Ini. Hyg. Assoc. J. 28:554 (Nov.-Dee. 1967). 54 DENSITY p(g/cm3) 15 -- 1* ? 13 -r 11 " 11 --m i "i 9 -j S-- 7-- *-- RATIO R/mpcf\ \mg/m3/ .0016 -3 .005 -- .1 -- MMD D(ptm) r- 10 --9 --8 -7 -6 -5 4 I 4-- I 3 10 -- 20 -- 30 40 50 100 -- 1-- 2. J .c 3 200 -- >oo too ICO '.5 Figure 1 -- Ratio of Particle Count -- mppcf to Respir able Mass Concentration -- mg/m3 (as function of density and mmd)t tPrepared by P. E. Caplan and R. J. Smith 55 SC 008175 LAM009385 sc 008176 Table 1 Equivalent TLVs in mppcf and mg/m3 (Respirable Mass) for Mineral Dustst Substance Threshold Limit Value Count Resp. Mass Total Mass* mppcf mg/m3 mg/m3 Silica (SiOi) Amorphous Cristobalite Fused silica Quartz Tridymite Coal Dust Diatomaceous earth, natural Graphite (natural) Mica Mineral wool fiber Nuisance particulates Perlite Portland Cement Soapstone Tripoli 20 1.5 3 3 1.5 (12) -- 15 20 -- 30 30 30 20 (3) (3)** 0.05 0.1 0.1 0.05 2 1.5 (2.5) (3) (5) (5) (5) (5) (3) 0.1 (6) 0.15 0.3 0.3 0.15 (4) -- (5) (6) 10 10 (10) (10) (6) (0.3) fAssuming that the mass median diameter is 1.5 (im and density is : g/cm3. `Unless otherwise specified, respirable mass is presumed to equal proximately 50% of total mass. "All values in parentheses () represent newly calculated values based on equivalence of 6 mppcf = 1 mg/m3 respirable mass and respirable mass s 5Q% total mass. APPENDIX G Chemical Substances and Other Issues Under Study1 Chemical Substances Acetonitrile Acrolein Acrylic acid Allyl chloride Amorphous silica Asbestos Atrazine Bismuth telluride 1,3-Butadiene Carbonyl fluoride Chlorinated naphthalenes Chlorine o-Chlorobenzlidene bis-Chloromethyl ether Chloromethyl methyl ether o-Chlorotoluene 56 Chrysene Copper dust & fume Cyclohexanone Diatomaceous earth Diethylenetriamine Epichlorohydrin Ethyl chloride Ethylene dichloride Ethyl methacrylate Gasoline Glycol ethers Graphite Hexachlorocyclopentadiene Isocyanates Isoflurane Isooctyl alcohol Jet fuels Methylenedianiline Methyl methacrylate Methyl tetiary butyl ether Nickel, metal & soluble compounds p-Nitrochlorobenzene Osmium tetroxide Perfluorinated chemicals Piperizine Propylene chloride Propylene oxide Styrene, monomer Tetrachloronaphthalene Tin hydride 1,2,3-Trichloropropane Trimellitic anhydride m-Xylene 2,2'-diamine (MXDA; meta-metaxylenediamine) Other Issues 1. Is the current aspect ratio better than other ratios for health protection and/or differentiation of asbestos fibers. 2. Ceiling Limits -- In light of today's instrumentation (quick response) and STELS, are ceiling limits need ed and, if so, what criteria would determine their ap propriateness. 3. Soluble Inorganic Compounds -- What quantitative criteria should be used in differentiating between sol uble and insoluble for TLV use. 4. Dual vapor and particulate TLVs.2 5. Should welding fume value (not otherwise classified, NOC) be retained or should specific analytical deter minations be made for metals and other compounds and these values be compared to specific TLVs? 'Information, data especially, and comments are solicited to assist the committee in its deliberations and in the development of draft docu ments. Draft documentations are used by the committee to decide what action, if any, to recommend on a given substance or question. 2Study papers appear in the Annals of the American Conference of Govemmental Industrial Hygienists, Volume 4, ACGIH Transactions - 19S2, pp. 153-155 (1983). 57 LAM009386 APPENDIX H Registered Trade Names Trade Name Generic Name Abate Am mate Azodrin Baygon Baytex Bidrin Bolstar Butyl Cellosolve Cellosolve acetate Coyden Crag herbicide Dasanit Delnav Dibrom Difolatan Disyston Dursban Oyfonate Furadan Guthion Lannate Methyl Cellosolve Methyl Cellosolve acetate Nemacur Nialate N-Serve Pival Plictran Sencor Sevin Teflon Thimet Thiodan Tordon Zoalene Temephos Ammonium sulfamate Monocrotophos Propoxur Fenthion Dicrotophos Sulprofos 2-Butoxyethanol 2-Ethoxyethyl acetate Clopidol Sesone Fensulfothion Dioxathion Naled Captafol Disulfoton Chlorpyrifos Fonofos Carbofuran Azinphos-methyl Methomyl 2-Methoxyethanol 2-Methoxyethyl acetate Fenamiphos Ethion Nitrapyrin Pindone Cyhexatin Metribuzin Carbaryl Polytetrafluoro- ethylene Phorate Endosulfan Picloram Dinitolmide CAS No. 3383-96-8 7773-06-0 6923-22-4 114-26-1 55-38-9 141-66-2 35400-43-2 111-76-2 111-15-9 2971-90-6 136-78-7 115-90-2 78-34-2 300-76-5 2425-06-1 298-04-4 2921-88-2 944-22-9 1563-66-2 86-50-0 16752-77-5 109-84-4 110-49-6 22224-92-6 563-12-2 1929-82-4 83-26-1 13121-70-5 21087-64-9 63-25-2 9002-84-0 298-02-2 115-29-7 1918-02-1 148-01-6 58 TLVs Threshold Limit Values for Physical Agents in the Work Environment Adopted by ACGIH for 1983-84 SC 008177 LAM009387 1982-83 TLV PHYSICAL AGENTS COMMITTEE Herbert H. Jones (Retired) -- Chairman Peter A. Breysse, University of Washington Thomas Cummings (Retired) Irving H. Davis, Michigan Dept, of Public Health Zory R. Glaser, Ph.D., National Center for Devices & Radiological Health/FDA Allan P. Heins, Ph.D., OSHA LCDR Richard Johnson, USN Edward J. Largent (Retired) John C. Mitchell, USAF Anthony M. Muc, Ph.D., Ontario Ministry of Labour William E. Murray, NIOSH (returned to member status 5/83) Wordie H. Parr, Ph.D. (Retired) (returned to member status 5183) David H. Sliney, USAEHA COL Robert T. Wangemann, USA Thomas K. Wilkinson, National Institutes of Health Gerald V. Coles CONSULTANTS This book is fully protected by copyright and no part of it may be reproduced in any form, by print, photoprint, microfilm, or any other means without written permission. Any comments or questions regarding these limits, or requests to reprint should be addressed to: Executive Secretary American Conference of Governmental Industrial Hygienists 6500 Glenway Ave., Bldg. D-5 Cincinnati, OH 45211: (513)661-7881 008178 60 PREFACE PHYSICAL AGENTS These threshold limit values refer to levels of phys ical agents and represent conditions under which it is believed that nearly all workers may be repeatedly ex posed day after day without adverse effect. Because of wide variations in individual susceptibility, expo sure of an occasional individual at, or even below, the threshold limit may not prevent annoyance, aggrava tion of a pre-existing condition, or physiological dam age. These threshold limits are based on the best avail able information from industrial experience, from ex perimental human and animal studies, and when pos sible, from a combination of the three. These limits are intended for use in the practice of industrial hygiene and should be interpreted and ap plied only by a person trained in this discipline. They are not intended for use, or for modification for use, (1) in the evaluation or control of the levels of physi cal agents in the community, (2) as proof or disproof of an existing physical disability, or (3) for adoption by countries whose working conditions differ from those in the United States of America. These values are reviewed annually by the Com mittee on Threshold Limits for Physical Agents for re visions or additions, as further information becomes available. Notice of Intent -- At the beginning of each year, proposed actions of the Committee for the forthcom ing year are issued in the form of a "Notice of Intent." This notice provides not only an opportunity for com ment, but solicits suggestions of physical agents to be added to the list. The suggestions should be ac companied by substantiating evidence. As Legislative Code -- The Conference recognizes that the Threshold Limit Values may be adopted in legislative codes and regulations. If so used, the in tent of the concepts contained in the Preface should be maintained and provisions should be made to keep the list current. 61 LAM009388 THRESHOLD LIMIT VALUES HEAT STRESS These Threshold Limit Values refer to heat stress conditions under which it is believed that nearly all workers may be repeatedly exposed without adverse health effects. The TLVs shown in Table 1 are based on the assumption that nearly all acclimatized, fully clothed workers with adequate water and salt intake should be able to function effectively under the given working conditions without exceeding a deep body temperature of 38C.<1-21 Since measurement of deep body temperature is impractical for monitoring the workers' heat load, the measurement of environmental factors is required which most nearly correlate with deep body tempera ture and other physiological responses to heat. At the present time Wet Bulb Globe Temperature Index (WBGT) is the simplest and most suitable technique to measure the environmental factors. WBGT values are calculated by the following equations: 1. Outdoors with solar load: WBGT = 0.7 NWB + 0.2 GT + 0.1 DB 2. Indoors or Outdoors with no solar load: WBGT = 0.7 NWB + 0.3 GT where: WBGT = Wet Bulb Globe Temperature Index NWB = Natural Wet-Bulb Temperature DB = Dry-Bulb Temperature GT = Globe Temperature The determination of WBGT requires the use of a black globe thermometer, a natural (static) wet-bulb thermometer, and a dry-bulb thermometer. Higher heat exposures than shown in Table 1 are permissible if the workers have been undergoing medical surveillance and it has been established that they are more tolerant to work in heat than the average worker. Workers should not be permitted to continue their work when their deep body tempera ture exceeds 38.0"C. EVALUATION AND CONTROL I. Measurement of the Environment The instruments required are a dry-bulb, a natural wet-bulb, a.globe thermometer, and a stand. The 62 TABLE 1 Permissible Heat Exposure Threshold Limit Values (Values are given in C. WBGT) Work Load Work -- Rest Regimen Light Moderate Heavy Continuous work 30.0 26.7 25.0 75% Work -- 25% Rest, Each hour 30.6 28.0 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 measurement of the environmental factors shall be performed as follows: A. The range of the dry and the natural wet bulb ther mometer shall be -5C to 50C with an accuracy of 0.5C. The dry bulb thermometer must be shielded from the sun and the other radiant surfaces of the en vironment without restricting the airflow around the bulb. The wick of the natural wet-bulb thermometer shall be kept wet with distilled water for at least 1/2 hour before the temperature reading is made. It is not enough to immerse the other end of the wick into a reservoir of distilled water and wait until the whole wick becomes wet by capillarity. The wick shall 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 thermometer, covering the stem about one additional bulb length. The wick should always be clean and new wicks should be washed be fore using. B. A globe thermometer, consisting of a 15 cm. (6inch) diameter hollow copper sphere painted on the outside with a matte black finish or equivalent, shall be used. The bulb or sensor of a thermometer (range -5C to 100C with an accuracy of 0.5C) must be fixed in the center of the sphere. The globe thermom eter shall be exposed at least 25 minutes before it is read. 63 SC 008179 LAM009389 C. A stand shall be used to suspend the three ther mometers so that they do not restrict free air flow around the bulbs, and the wet-bulb and globe ther mometer are not shaded. D. It is permissible to use any other type of tempera ture sensor that gives identical reading as that of a mercury thermometer under the same conditions. E. The thermometers must be so placed that the readings are representative of the condition where the men work or rest, respectively. The methodology outlined above is more fully ex plained by Minard.13''11 II. Work Load Categories Heat produced by the body and the environmental heat together determine the total heat load. There fore, if work is to be performed under hot environ mental conditions, the workload category of each job 400 800 1200 1600 2000 Btu/hr Rote of Work Figure 1 -- Permissible Heat Exposure Threshold Limit Value 64 TABLE 2 Assessment of Work Load'9' Average values of metabolic rate during different activities. A. Body position and movement Sitting Standing Walking Walking up hill kcal/min 0.3 0.6 2.0-3.0 add 0.8 per meter (yard) rise B. Type of Work Average Range kcal/min kcal/mip Hand work light heavy 0.4 0.9 0.2-1.2 Work with one arm light 1.0 0.7-2.5 heavy 1.8 Work with both arms light heavy 1.5 2.5 1.0-3.5 Work with body light moderate heavy very heavy 3.5 5.0 7.0 9.0 2.515.0 shall be established and the heat exposure limit perti nent to the work load evaluated against the applica ble standard in order to protect the worker from ex posure beyond the permissible limit. A. The work load category may be established by ranking each job into light, medium, and heavy cate gories on the basis of type of operation. Where the work load is ranked into one of said three categories, i.e. (1) light work (up to 200 kcal/hr or 800 Btu/hr): e.g., sitting or standing to control machines, perform ing light hand or arm work, 65 W 0 G T - C SC 008180 LAM009390 SC 008181 TABLE 3 Activity Examples'91 Light hand work: writing, hand knitting Heavy hand work: typewriting Heavy work with one arm: hammering in nails (shoe maker, upholsterer) Light work with two arms: filing metal, planing wood, raking of a garden Moderate work with the body: cleaning a floor, beating a carpet Heavy work with the body: railroad track laying, digging, barking trees Sample Calculation Assembly line work using a heavy hand tool. A. Walking along 2.0 kcal/min B. Intermediate value between heavy work with two arms and light work with the body 3.0 kcal/min C. Add for basal metabolism 5.0 kcal/min 1.0 kcal/min Total 6.0 kcal/min (2) moderate work (200-350 kcal/hr or 800-1400 Btu/hr): e.g., walking about with moderate lifting and pushing, (3) heavy work (350-500 kcal/hr or 1400-2000 Btu/hr): e.g., pick and shovel work, the permissible heat exposure limit for that work load shall be determined from Table 1. B. The ranking of the job may be performed either by measuring the worker's metabolic rate while perform ing his job or by estimating his metabolic rate with the use of Tables 2 and 3. Additional tables available in the literature!5-81 may be utilized also. When this method is used the permissible heat exposure limit can be determined by Figure 1. 66 III. Work-Rest Regimen The permissible exposure limits specified in Table 1 and Figure 1 are based on the assumption that the WBGT value of the resting place is the same or very close to that of the work place. Where the WBGT of the work area is different from that of the rest area a time-weighted average value should be used for both environmental and metabolic heat. When timeweighted average values are used the appropriate curve on Figure 1 is the solid line labeled "continu ous." The time-weighted average metabolic rate (M) shall be determined by the equation: Mi x ti + M2 x fe + . . . . + M,, x t,' Av. M = ti + fe +....+ t. where Mi, M2 . . . and M,, are estimated or measured metabolic rates for the various activities and rest periods of the worker during the time periods ti, fe . .. and L (in minutes) as determined by a time study. The time-weighted average WBGT shall be deter mined by the equation: Av. WBGT = WBGTi x ti + WBGT2 x f2 + . . . + WBGT,, x t,, ti + ts + . . . + t,, where WBGTi, WBGT2 . .. and WBGT,, are calculated values of WBGT for the various work and rest occu pied during total time periods tt, t2 . . . and L, are the elapsed times in minutes spent in the corresponding areas which are determined by a time study. Where exposure to hot environmental conditions is continu ous for several hours or the entire work day, the timeweighted averages shall be calculated as hourly timeweighted average i.e., ti+t2 + ... + t,=60 minutes. Where the exposure is intermittent, the time-weighted averages shall be calculated as two-hour time-weight ed averages, i.e., ti + t2 + ... + t, = 120 minutes. The permissible exposure limits for continuous work are applicable where there is a work-rest regi men of a 5-day work week and an 8-hour work day with a short morning and afternoon break (approxi mately 15 minutes) and a longer lunch break (approx imately 30 minutes). Higher exposure limits are per mitted if additional resting time is allowed. All breaks, including unscheduled pauses and administrative or operational waiting periods during work may be 67 LAM009391 counted as rest time when additional rest allowance must be given because of high environmental temper atures. IV. Water and Salt Supplementation During the hot season or when the worker is ex posed to artificially generated heat, drinking water shall be made available to the workers in such a way that they are stimulated to frequently drink small amounts, i.e., one cup every 15-20 minutes (about 150 ml or 1/4 pint). The water shall be kept reasonably cool (10-15C or 50.0-60.0F) and shall be placed close to the workplace so that the worker can reach it without abandoning the work area. The workers should be encouraged to salt their food abundantly during the hot season and particu larly during hot spells. If the workers are unacclima tized, salted drinking water shall be made available in a concentration of 0.1% (1 g NaCI to 1.0 liter or 1 level tablespoon of salt to 15 quarts of water). The added salt shall be completely dissolved before.the water is distributed, and the water shall be kept reasonably cool. V. Other Considerations A. Clothing: The permissible heat exposure TLVs are valid for light summer clothing as customarily worn by workers when working under hot environmental conditions. If special cothing is required for perform ing a particular job and this clothing is heavier or it impedes sweat evaporation or has higher insulation value, the worker's heat tolerance is reduced, and the permissible heat exposure limits indicated in Table 1 and Figure 1 are not applicable. For each job catego ry where special clothing is required, the permissible heat exposure limit shall be established by an expert. B. Acclimatization and Fitness: Acclimatization to heat involves a series of physiological and psycholog ical adjustments that occur in an individual during his first week of exposure to hot environmental condi tions. The recommended heat stress TLVs are valid for acclimated workers who are physically fit. Extra caution must be employed when unacclimated or physically un-fit workers must be exposed to heat stress conditions. Rafarancas: 1. Health Factors Involved in Working Under Conditions of Heat Stress. WHO Technical Report Series No. 412 (1969). 68 008182 2. Dukat-Dobo*. F. N. and A. Hanjchal: Development of Permissible Heat Exposure Limits for Occupational Work. ASHRAE Journal f5(9):57-62(Sept. 1973). 3. Mlnard, D.: Prevention of Heat Casualties in Marine Corps Recruits, Period of 1955-60, with Comparative Incidence Rates and Climatic Heat Stresses in Other Training Categories. Research Report No. 4, Contract No. MR 005.01-0001.01, Naval Medical Research Inshtue, Bethesda, M0 (Feb. 21, 1961). Published in Military Medicine 126(44): 261-272 (April 1961). 4. Mlnard, 0. and R. L. O'Brien: Heat Casualties in the Navy and Marine Corps 1959-1962 with Appendices on the Field Use of the Wet Bulb-Globe Temperature Index. Research Report No. 7, Contract No. MR 005.01-0001.01, Naval Medical Research Institute. Bethes da, MD (March 12. 1964). 5. Aatrand, Per-Olof and Kaara Rodahl: Textbook of Work Physiology. McGraw-Hill Book Co., New York, San Francisco (1970). 6. Ergonomics Guide to Assessment of Metabolic and Cardiac Costs.of Physical Work. Am. Ind. Hyg. Assoc. J. 32:560 (1971). 7. Energy Requirements for Physical Work. Research Progress Report No. 30. Purdue Farm Cardiac Project, Agricultural Experiment Sta tion, West Lafayette. IN (1961). 8. Dunlin, J. V. G. A. and R. Passmore: Energy, Work and Leisure. Heinemann Educational Books, Ltd., London (1967). 9. Lehmann, G. E., A. Muller and H. Spitzer Der Kalorienbedarf bie Gewerblicher Arbeit. Arbeitsphysiot. 74:166 (1950). IONIZING RADIATION The Committee accepts the philosophy and recom mendations of the National Council on Radiation Pro tection and Measurements (NCRP) for the ionizing ra diation TLV. The NCRP is charted by Congress to, in part, collect, analyze, develop and disseminate infor mation and recommendations about protection against radiation and about radiation measurements, quantities and units, including development of basic concepts in these areas. NCRP Report No. 39 pro vides basic philosophy and concepts leading to pro tection criteria established in the same report.11' Other NCRP reports address specific areas of radiation pro tection and, collectively, provide an excellent basis for establishing a sound program for radiation con trol. The Committee recommends the listed refer ences as substantative documentation of a sound basis for ionizing radiation protection. The committee also strongly recommends that all exposures to ioniz ing radiations be kept as low as reasonably achiev able within the stated guidance. Refarencas: 1. Basic Radiation Protection Criteria. NCRP Report No. 39 (January 15, 1971). 69 LAM009392 sc 008183 2. Maximum Permissible Body Burdens and Maximum Permissible Con centrations ol Radionuclides in Air and in Water for Occupational Ex posure. National Bureau of Standards Handbook 69, (June 5,19S9), with Addendum 1 (August 1963). Available as NCRP Report No. 22. The above documents, as well as Information on nu merous other NCRP Reports addressing specific sub jects in ionizing radiation protection are available from: NCRP Publications, PO Box 30175, Washing ton, DC 20014. USERS The threshold limit values are for exposure to laser radiation under conditions to which nearly all workers may be exposed without adverse effects. The values should be used as guides in the control of exposures and should not be regarded as fine lines between safe and dangerous levels. They are based on the best available information from experimental studies. Limiting Apertures The TLVs expressed as radiant exposure or irradiance in this section may be averaged over an aper ture of 1 mm except for TLVs for the eye in the spec tral range of 400-1400 nm, which should be averaged over a 7 mm limiting aperture (pupil); and except for all TLVs for wavelengths between 0.1-1 mm where the limiting aperture is 10 mm. No modification of the TLVs is permitted for pupil sizes less than 7 mm. The TLVs for "extended sources" apply to sources which subtend an angle greater than a (Table 7) which varies with exposure time. This angle is not the beam divergence of the source. Correction factors A and B (CA and CB) The TLVs for ocular exposure in Tables 4 and 5 are to be used as given for all wavelength ranges. The TLVs for wavelengths between 700 nm and 1049 nm are to be increased by a uniformly extrapolated factor (CA) as shown in Figure 2. Between 1049 nm and 1400 nm, the TLV has been increased by a factor (Q,) of five. For certain exposure times at wavelengths be tween 550 nm and 700 nm, correction factor (CB) must be applied. The TLVs for skin exposure are given in Table 6. The TLVs are to be increased by a factor (C,) as shown in Figure 2 for wavelengths between 700 nm and 1400 nm. To aid in the determination of TLVs for exposure durations requiring calculations of fraction al powers Figures 3, 4, 5 and 6 may be used. 70 Repetitively Pulsed Lasers Since there are few experimental data for multiple pulses, caution must be used in the evaluation of such exposures. The protection standards for irradiance or radiant exposure in multiple pulse trains have the following limitations: (1) The exposure from any single pulse in the train is limited to the protection standard for a single com parable pulse. (2) The average irradiance for a group of pulses is limited to the protection standard as given in Tables 4, 5, or 7 of a single pulse of the same duration as the entire pulse group. (3) When the Instantaneous Pulse Repetition Fre quency (PRF) of any pulses within a train exceeds one, the protection standard applicable to each pulse is reduced as shown in Figure 6 for pulse durations less than 10~5 second. For pulses of greater duration, the following formula should be followed: I sinqle pulse\ Standard (pulse nr) Standard (jn train ) -----------------,,----------- where: n = number of pulses in train r = duration of a single pulse in the train Standard (nr) = protection standard of one pulse having a duration equal to r>T sec onds. Figure 2 -- TLV correction factor for \ = 700 - 1400 nm* *For\ = 700 - 1049 nm, C< = lO10 002'*-- 700,1 Fork = 1050 - 1400 nm, C,, =5 71 LAM009393 cm -2 0.1 W cm-2 2 J m * c T 320 C *,,W c n r 2 9(t/ V "T ") mJ c n r ; J V 10-2 0.56 10-4 to 10a 103to 3 x 1 0 4 10 " to 10"T" 10-' to 10 10 to 3 x IQ4 TABLE 4 Threshold Limit Value for Direct Ocular Exposures (Intrabeam Viewing) from a Laser Beam "D oo "w o o ooo 1O CO l-O O CO O CD to O CO COCO^<0'-- -- CM^rCOi-- -r-- CM ^ CO ,I--PE -weo 05 ?? co/> C._O , CO o; ee ee O CM oo o CM CO EEEEEEEEEEEEEE ppppccippccrcecc oOoCcOoTOfOtflOtrtOsoOoOaOiOTT~-fW-f-C-rT-f^-- CM CM CO CO CO CO CO CO CO CO CO CO CO CO ^ o o ao S'oH > > 72 C| E,, Eg:cbP?i?V- o gX S - C- E -oe a. ,u; >oXo,,to,, ,00 X O in *-- in oo x2 o_ r-> X :x X. C^O j_ l a &co^2o - oco O r osr x O O Q o -- x r* o o o o co- o o *~i T o I o OO 1 o EEI EC : Ec o o h- o Ec o o f"- o Ec O) min o Ee o o r- 2 Ee o of*- E o oh c O o c a> O o o oT'T~ --o EEEEEEEEI o o o o ooT oLt-OO <lt - c co 5 oo m 5r0ss0r0- <c cc 73 1050 nm to 1400 nm 700 nm to 1400 nm 1.4/xm to10Vm "" IR -B & C sc 008184 LAM009394 TABLE 5 Threshold Limit Values for Viewing a Diffuse Reflection of a Laser Beam or an Extended Source Laser 1.0 for X = 400-700 nm; see Figure 2 for X = 700 to 1400 nm. C/5 Eo -I I - E' EL - CO 0 <*> ^ JJ3 I XZ -3 Eo .3 O , oE X I EO ^05 JD re o ^ -- .o O CO t*3o* 0C=3 TO CO r- CM CO CM CM -- CO O CO t= c o.-o~1 nvo- o t- wo o al sf ^Q Q o** ^ al Q AI oooo -ooooo eeeeeeIIIe CCCCCCqq^ 3. SOo'OO'OOOOOOTOj-OTrOon-o ry* fs, CO N- N N v-- t-- t-- OOOOOOOOOO EcEcEcEcEcEcEcEccEE^ ooooootoomo oooooo oo - CO C .b o a; CO c o oa < CD cc cc 74 sc 008185 ^r # Eco 03 CO .O -^O oL H-- fn'-r5 w <2 ,.00 CO C\J t-- o CO o oo CL N O V X UJ ^C JaC CO r- X CO cOo CO 0 O O CO o CO CL^ A A t O O1 OI IO*o* OI >E E a. B gO*<r oT*--T,- : & 03 o o e Ec e a. o2 oo : CM O 08 a > ^<=:o> <ct<reCeD 75 LAM009395 SC 008186 t l v r a d ia n t EttPOSuRE j( T LV IRRAO IANCE ( W - c m - * > Figure 3a -- TLV for intrabeam (direct) viewing of laser beam (400-700 nm). i ! Figure 4a -- TLV for laser exposure of skin and eyes for far-in; frared radiation (wave-lengths greater than 1.4 I jim). EXPOSURE DURATION (51 Figure 3b -- TLV for intrabeam (direct) viewing of CW laser beam (400-1400 nm) 76 Figure 4b -- TLV for CW laser exposure of skin and eyes for far-infrared radiation (wave-lenglhs greater than 1.4 JilTl). 77 LAIVI009396 TLV INTEGRATED RAOIANCE 1 J c m '* *r* Figure 5b -- TLV for extended sources or diffuse reflections of laser radiation (400-1400 nm). 78 Figure 6 -- Multiplicative correction factor for repetitively pulsed lasers having pulse durations less than IO"5 second. TLV for a single pulse of the pulse train is multiplied by the above correction factor. Correction factor for PRF greater than 1000 Hz is 0.06. TABLE 7 Limiting Angle to Extended Source Which May Be Used for Applying Extended Source TLVs Exposure Duration(s) 10"9 io-8 io-7 io-6 io-5 10-" io-3 Angle a (mrad) 8.0 5.4 3.7 2.5 1.7 2.2 3.6 Exposure Duration(s) io-2 io-> 1.0 10 102 IO3 10" Angle a (mrad) 5.7 9.2 15 24 24 24 24 79 SC 008187 LAM009397 NOISE These threshold limit values refer to sound pres sure levels and durations of exposure that represent conditions 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. Prior to 1979, the medical profession had de fined hearing impairment as an average hearing threshold level in excess of 25 decibels (ANSI-S3.61969) at 500, 1000, and 2000 Hz, and the limits which are given have been established to prevent a hearing loss in excess of this level.<a) The values should be used as guides in the control of noise exposure and, due to individual susceptibility, should not be regard ed as fine lines between safe and dangerous levels. It should be recognized that the application of the TLV for noise will not protect all workers from the ad verse effects of noise exposure. A hearing conserva tion program with audiometric testing is necessary when workers are exposed to noise at or above the TLV levels. Continuous or Intermittent The sound level shall be determined by a sound level meter, conforming as a minimum 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 network with slow meter response. Duration of exposure shall not ex ceed that shown in Table 8. These values apply to total duration of exposure per working day regardless of whether this is one continuous exposure or a number of short-term expo sures and does include the impact and impulsive type of noise that contributes to the sound level meter reading at slow response. When the daily noise exposure is composed of two or more periods of noise exposure of different levels, their combined effect should be considered, rather than the individual effect of each. If the sum of the following fractions: Ci Ca Cr, IT Ta ' ' T,, exceeds unity, then, the mixed exposure should be considered to exceed the threshold limit value, Ci in- ln 1979, the American Academy of Ophthalmology and Otolargyngology (AA00) included 3000 Hz in their hearing impairment formula. 80 Table 8 Threshold Limit Values Duration per Day Hours 16 8 4 2 1 1/2 1/4 1/8 Sound Level dBAt 80 85 90 95 100 105 110 115* tSound level In decibels are measured on a sound level meter, conform-' ing as a minimum to the requirements of the American National Stan dard Specification for Sound Level Meters, S1.4 (1971) Type S2A, and set to use the A-weighted network with slow meter response. No exposure to continuous or intermittent in excess of 115 dBA dicates the total duration of exposure at a specific noise level, and Ti indicates the total duration of ex posure permitted at that level. All on-the-job noise ex posures of 80 dBA or greater shall be used in the above calculations. IMPULSIVE OR IMPACT NOISE It is recommended that exposure to impulsive or impact noise shall not exceed the limits listed in Table 9 or taken from Figure 7. No exposures in ex cess of 140 decibels peak sound pressure level are permitted. Impulsive or impact noise is considered to be those variations in noise levels that involve max ima at intervals of greater than one per second. Where the intervals are less than one second, it should be considered continuous. Table 9 Threshold Limit Values Impulsive or Impact Noise Sound Level dB" 140 130 120 Permitted Number of Impulses or Impacts per day 100 1000 10,000 "Decibels peak sound pressure level, re 20 ^Pa 81 SC 008188 LAM009398 NUMRER OF IMPULSES OR IMPACTS PER OAT (N) Figure 7 -- Threshold Limit Values for Impulse/Impact Noise. $RADIOFREQUENCY/MICROWAVE RADIATION These Threshold Limit Values (TLVs) refer to ra diofrequency (RF) and microwave radiation in the fre quency range from 10 kHz to 300 GHz, and represent conditions'under which it is believed workers may be repeatedly exposed without adverse health effects. The TLVs shown in Table 10 are selected to limit the average whole body specific absorption rate (SAR) to 0.4 W/kg in any six minutes (0.1 hr) period for 3 MHz to 300 GHz, see Figure 8. Between 10 kHz and 3 MHz the average whole body SAR is still limited to 0.4 W/kg, but the plateau at 100 mW/cm2 was set to pro tect against shock and bum hazards. Since it is usually impractical to measure the SAR, the TLVs are expressed in units that are measurable, viz, squares of the electric and magnetic field strengths, averaged over any 0.1 hour period. This 11983 Adoption. 82 sc 008189 83 LAM009399 Figure 8 -- Threshold Limit Values (TLV) for Radiofrequency/Microwave Radiation in Workplace (Whole Body SAR Less Than 0.4 W/kg). Radiofrequency/Microwave Threshold Limit Values SC 00819 03 _ <a. 5? ^ s 82 co 2L X ^ rr*^- r^-. w' lo ttoo c^o cosj C;- CcD\i NOOi.d CD CT3 _ oX Xo oo - o O o fc. r--- r-- r-- r-- rs~. fs. k fs. h-- co co co co co 2^ o o o ro o T-o T- Oi T- _ >*- |S55o -- OCO Oo oo oo 1-OfO cr o 3 S 3 52550 O CO o O -- CO o ii 84 can be expressed in units of equivalent plane wave power density for convenience. The electric field strength (E) squared, magnetic field strength (H) squared, and power density (PD) values are shown in Table 10. For near field exposures PD cannot be mea sured directly, but equivalent plane wave power den sity can be calculated from the field strength mea surement data as follows: PD in mW/cm2 = -rj^r where: E2 is in volts squared (V2) per meter squared (m2). where: PD in mW/cm2 = 37.7 H2 H2 is in amperes squared (A2) per meter squared (m2). These values should be used as guides in the eval uation and control of exposure to radiofrequency/mi crowave radiation, and should not be regarded as a fine line between safe and dangerous levels. Notes: 1. All Radiofrequency Radiation (RFR) exposures should be kept as low as reasonably possible given the current state of knowledge on human effects, particularly non-thermal effects. 2. For fields consisting of a number of frequencies, the fraction of the protection guide incurred within each frequency level should be determined and the sum of all fractions should not exceed unity. 3. For pulsed and continuous wave fields, the power density is averaged over the six minute period. 4. For partial body exposures at frequencies between 10 kHz and 1.0 GHz, the protection guides in Table 10 may be exceeded if the output power of a ra diating device is 7 watts or less. For example, if a hand held transmitter operating at 27 MHz has a maximum output of 5 watts, it would be excluded from any further field measurements. 5. The TLVs in Table 10 may be exceeded if the expo sure conditions can be demonstrated to produce a SAR of less than 0.4 W/kg as averaged over the whole body and spatial peak SAR values less than 8.0 W/kg as averaged over any 1.0 gram of tissue. 85 . , LAM009400 For example, for frequencies from 3 to 30 MHz, the equivalent power density can be increased by a factor of 10 up to a limit of 100 mW/crn2, if it can be assured that exposed individuals are not in con tact with the ground plate. 6. At frequencies below 30 MHz, ungrounded objects such as vehicles, fences, etc., can strongly couple to RF fields. For field strengths near the TLV, shock and bum hazards can exist. Care should be taken to eliminate ungrounded objects, to ground such objects, or use insulated gloves when un grounded objects must be handled. 7. No measurement should be made within 5 cm of any object. 8. All exposures should be limited to a maximum (peak) electric fielci intensity of 100 kV/m. ULTRAVIOLET RADIATION* These threshold limit values refer to ultraviolet ra diation in the spectral region between 200 and 400 nm and represent conditions under which it is be lieved that nearly all workers may be repeatedly ex posed without adverse effect. These values for expo sure of the eye or the skin apply to ultraviolet radiation from arcs, gas, and vapor discharges, fluo rescent, and incandescent sources, and solar radia tion, but do not apply to ultraviolet lasers.' These val ues do not apply to ultraviolet radiation exposure of photosensitive individuals or of individuals concomi tantly exposed to photosensitizing agents.11' These values should be used as guides in the control of ex posure to continuous sources where the exposure duration shall hot be less than 0.1 sec. These values should be used as guides in the con trol of exposure to ultraviolet sources and should not be regarded as a fine line between safe and danger ous levels. Recommended Values: The threshold limit value for occupational expo sure to ultraviolet radiation incident upon skin or eye where irradiance values are known and exposure time is controlled are as follows: 1. For the near ultraviolet spectral region (320 to 400 nm) total irradiance incident upon the unprotected 'See User TLVs. 86 skin or eye should not exceed 1 mW/cm2 for periods greater than 103 seconds (approximately 16 minutes) and for exposure times less than 103 seconds should not exceed one J/cm2. 2. For the actinic ultraviolet spectral region (200 -- 315 nm), radiant exposure incident upon the un protected skin or eye should not exceed the values given in Table 11 within an 8-hour period. 3. To determine the effective irradiance of a broad band source weighted against the peak of the spectral effectiveness curve (270 nm), the follow ing weighting formula should be used: Ea = IE,SXA\ where: E= effective irradiance relative to a monochromat ic source at 270 nm in W/cm2 (J/s/cm2) E* = spectral irradiance in W/cm2/nm Sx = relative spectral effectiveness (unitless) AA. = band width in nanometers Figure 9 -- Threshold Limit Values for Ultraviolet Radiation 87 sc 008191 LAM009401 sc 008192 TABLE 11 Relative Spectral Effectiveness by Wavelength* Wavelength (nm) 200 210 220 230 240 250 254 260 270 280 290 300 305 310 315 TLV (mJ/cm2) 100 40 25 16 10 7.0 6.0 4.6 3.0 3.4 4.7 10 50 200 1000 Relative Spectral Effectiveness s. 0.03 0.075 0.12 0.19 0.30 0.43 0.5 0.65 1.0 0.88 0.64 0.30 0.06 ' 0.015 0.003 `See Laser TLVs. TABLE 12 Permissible Ultraviolet Exposures Duration of Exposure Per Day Effective Irradiance, E,,rf (mW/citi2) 8 hrs......... :.... ......... 4 hrs................ ......... 2 hrs................ ......... 1 hr.................. ......... 30 min............. ......... 15 min................................................... 10 min................................................... 5 min..................................................... 0.1 0.2 0.4 0.8 1.7 3.3 5 10 1 min..................................................... 50 30 sec................................................... 100 10 sec................................................... 300 1 sec..................................................... 3,000 0.5 sec.................................................. 6,000 0.1 sec...................................................30,000 88 4. Permissible exposure time in seconds for expo sure to actinic ultraviolet radiation incident upon the unprotected skin or eye may be computed by dividing 0.003 J/cm2 by E,// in W/cm2. The expo sure time may also be determined using Table 12 which provides exposure times corresponding to effective irradiances in^W/cm2. 5. All the preceding TLVs for ultraviolet energy apply to sources which subtend an angle less than 80. Sources which subtend a greater angle need to be measured only over an angle of 80. Conditioned (tanned) individuals can tolerate skin exposure in excess of the TLV without erythemal ef fects. However, such conditioning may not protect persons against skin cancer. Reference: 1. Sunlight and Man. Fitzpatrick et a/, Eds. Univ. of Tokyo Press, Tokyo. Japan (1974). NOTICE OF INTENDED CHANGES (for 1983-84) These physical agents, with their corresponding values, comprise those for which either a limit has been proposed for the first time, or for which a change in the "Adopted" listing has been proposed. In both cases, the proposed limits should be consid ered trial limits that will remain in the listing for a period of at least one year. If after one year no evi dence comes to light that questions the appropriate ness of the values herein the values will be reconsi dered for the "Adopted" list. NOTICE OF INTENT TO ESTABLISH THRESHOLD LIMIT VALUES USERS It is proposed that the following footnote be added to Table 6 (Threshold Limit Value for Skin Exposure from a Laser Beam). The IR-B and IR-C exposures to skin surface areas A(cm2) exceeding 1000 cm2, the TLV is (100,000/A) (mW/cm2); for areas greater than 100,000/A, the TLV is 10 mW/cm2. LIGHT AND NEAR-INFRARED RADIATION These Threshold Limit Values refer to visible and near-infrared radiation in the wavelength range of 400 89 LAM009402 nm to 1400 nm and represent conditions under which it is believed that nearly all workers may be exposed without adverse effect. These values should be used as guides in the control of exposure to light and should not be regarded as a fine line between safe and dangerous levels. Recommended Values: The Threshold Limit Value for occupational expo sure to broad-band light and near-infrared radiation for the eye apply to exposure in any eight-hour work day and require knowledge of the spectral radiance (Lx) and total irradiance (E) of the source as mea- TABLE 13 Spectral Weighting Functions for Assessing Retinal Hazards from Broad-Band Optical Sources Wavelength (nm) 400 405 410 415 420 425 430 435 440 445 450 455 460 465 470 475 480 485 490 495 500-600 600-700 700-1049 1050-1400 Blue-Light Hazard Function Bx 0.10 0.20 0.40 0.80 0.90 0.95 0.98 1.0 1.0 0.97 0.94 0.90 0.80 0.70 0.62 0.55 0.45 0.40 0.22 0.16 *| QI(450--Aj/50) 0.001 0.001 0.001 Burn Hazard Function Rx . .1.0 2.0 4.0 8.0 9.0 9.5 9.8 10 10 9.7 9.4 9.0 8.0 7.0 6.2 5.5 4.5 4.0 2.2 1.6 1.0 1.0 *| 01(700--A)/5051 0.2 90 sured at the position(s) of the eye of the worker. Such detailed spectral data of a white light source is gener ally only required if the luminance of the source ex ceeds 1 cd cm-2. At luminances less than this value the TLV would not be exceeded. The TLV's are: 1. To protect against retinal thermal injury, the spec tral radiance of the lamp weighted against the function R (Table 13) should not exceed: 1400 'h 2 L*RxAX 1/ort 400 (1)* where Lk is in W cm~2 sr1 and t is the viewing du ration (or pulse duration if the lamp is pulsed) lim ited to 1 /j.s to 10 s, and a is the angular subtense of the source in radians. If the lamp is oblong, a refers to the longest dimension that can be viewed. For instance, at a viewing distance r = 100 cm from a tubular lamp of length I = 50 cm, the view ing angle is: a =l/r = 50/100 = 0.5 rad (2) 2. To protect against retinal photochemical injury from chronic blue-light exposure the integrated spectral radiance of a light source weighted against the blue-light hazard function Bk (Table 13) should not exceed: 1400 ^ Lx t Bx AX s 100 Jcnr2 sr1 (t ^ los) (3a) 1400 L,, Bx AX 10-2 Wcnr2 sr1 (t > 104s) (3b) The weighted product of Lx and BK is termed L(blue). For a source radiance L weighted against the blue-light hazard function [L(blue)] which ex ceeds 10 mW^cnr^sr1 in the blue spectral re gion, the permissible exposure duration L.,,, in seconds is simply: Wr = 100 J cm-2 sr'/L (blue) (4) The latter limits are greater than the maximum per missible exposure limits for 440 nm laser radiation (see Laser TLV) because a 2-3 mm pupil is as sumed rather than a 7 mm pupil for the Laser TLV. For a light source subtending an angle a less than 11 mrd (0.011 radian) the above limits are relaxed such that the spectral irradiance weighted against the blue-light hazard function Bx should not ex ceed E(blue). 91 SC 008193 LAM009403 sc 008194 1400 2, Ei t Bk AX s 10 mJ cm-2 (t S 104 s) (5a) 1400 Bx AX g VW cm2 (ts 10*5) (5b) For a source where the blue light weighted irradiance E (blue) exceeds 1 fiW cnr2 is the maxi mum permissible exposure duration t,,0J. in sec onds is: Wr = 10 mJ cm"2 E (blue) (6) 3. Infrared Radiation: To avoid possible delayed ef fects upon the lens of the eye (cataractogenesis), the infrared radiation (X > 770 nm) should be lim ited to 10 mWcm-2. For an infrared heat lamp or any near-infrared source where a strong visual stimulus is absent, the near infrared (770-1400 nm) radiance as viewed by the eye should be limited to: 1400 ^ Lx AX = 0.6/a (7)* for extended duration viewing conditions. This limit is based upon a 7 mm pupil diameter. AIRBORNE UPPER SONIC AND ULTRASONIC ACOUSTIC RADIATION These threshold limit values refer to sound pres sure levels that represent conditions under which it is believed that nearly all workers may be repeatedly ex posed without adverse effect. The values listed in Table 14 should be used as guides in the control of noise exposure and, due to individual susceptibility, should not be regarded as fine lines between safe and dangerous revels. The levels for the third octave bands centered below 20 kHz are below those which cause subjective effects. Those levels for 1/3 octaves above 20 kHz are for prevention of possible hearing losses from subharmonics of these frequencies. 'Formulae (1) and (7) are empirical and are not, strictly speaking, di mensionally correct. To make the formulae dimensionally correct, one would have to insert a dimensional correction factor k in the right hand numerator in each formula. For formula (1) this would be k, = 1 W rad sVi/jcm*1 2 3s4r),5 a6nd for formula (7) K = 1 W rad/jcm2 sr), 92 ' TABLE 14 Permissible Ultrasound Exposure Levels Mid-Frequency of Third-Octave Band kHz 10 12.5 16 20 25 31.5 40 50 One-Third Octave -- Band Level in dB re 20 ptPa 80 80 80 105 110 115 115 115 PHYSICAL AGENTS UNDER STUDY The Physical Agents Committee of ACGIH has ex amined the current literature and has not found suffi cient information to propose a TLV. However, these agents will remain under study during the coming year to examine new evidence indicating the need and feasibility for establishing a proposed TLV. Com ments and suggestions, accompanied by substantive documentation are solicited and should be forwarded to the Executive Secretary, ACGIH, Documentation summarizing the current status of the biological ef fects literature is available on those agents preceded by an asterisk (*). 1. `Extremely Low Frequency (ELF) Radiation. Spe cifically, that portion of the spectrum from 0 to 300 Hz. 2. Magnetic Fields. Both pulsed and 'continuous. 3. Laser Radiation. Specifically laser exposures of less than one (1) nanosecond. 4. Vibration. Segmental and whole-body. 5. Cold Stress. 6. Pressure Variations. 93 LAM003404 ^Viarryg* e^rr-psis^;^ dwfcisi i.r-nann- .\<AT$o.gf.2ai? ^KrtcriEJXlffir [\K>Wi<Min j-jj^nijc, jj-.i a^tiEC^fc&E? uiafegifo 'ICTfSpB'* !i?3iP nm<px-r- ^,jcsiy-i:3irrj^ariayff.^<33 OiETPlS'rm'-'* SJ&l? "ir> wf."rJ.in'nw.'.-n,u jit-bfin-j-v. to? ;crjiif n.'-rc-'<,,lr' "^issav arru a** ,;y> C3afflitfr- Or 11*:['-!'rli /a!m(*TO- Tty 'itUT-ity" JpG&" .'.(H vJ/srimulKty ( lijasftu- <f* fa&JafeijtijiJr -1 ", /^,'T<^iD'in j-;`fit9c;fO.r^0l^I}?naR'T3iliijUij'-'K Jt1- ROTty>'7- ooH-iiiffOra* 'PsVW, !l.n[M^tH.;.i,'ir!l- HrEyiiKIV iitJi^'-iSil'^unM) fC*fiTKl*ii?5S-^ <' iK't `5a^jip>.iT'>i'rir;n!rr^ jjjty .jit > v w.fPu/i^aM^j, 1 LAIVI009405 LAM009406