Document QXKB4rp6K5o6yrkdpqpyd9VYv

\ PLAINTIFF'S EXHIBIT MON-2481 SC 008197 LAM009407 H.p j^ijjiin issii.gr. ;K$0}, -.c^.^r,. i-y-^nif*w)yu >iiv^ifr-rajSiiiirHaHXgstrnr^isiijKr^-^.<\<i ji'XnVrv.r'irw TLVs Threshold Limit Values for Chemical Substances in Work Air Adopted by ACGIH for 1982 l>VStii.` iUftfrjF fife* (WT?Wilia's: ' LAM009408 1982 TLV AIRBORNE CONTAMINANTS COMMITTEE Vernon L. Carter, D.V.M. -- Chairman Melvin E. Andersen, Ph.D., USAF B. Dwight Culver, M.D., University of Califomia-Irvine James W. Hammond, University of Texas 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 Uni versity Mary K. Murphy, OSHA Leonard D. Pagnotto, Massachusetts Dept, of Labor & Industry -- Secretary Ronald S. Ratney, OSHA Meier Schneider, P.E., C.I.H., City of Los Angeles Robert Spirtas, Dr. PH, National Cancer Institute Vera F. Thomas, Ph.D., University of Miami William D. Wagner, NIOSH Elizabeth K. Weisburger, Ph.D., National Cancer Insti tute CONSULTANTS Paul Gross, M.D. Georg Kimmerle, M.D., German MAK Commission Li aison Trent R. Lewis, Ph.D. Ernest Mastromatteo, M.D. James F. Morgan George Rausch, M.D. Marshall Steinberg, Ph. D. Theodore R.-Torkelson, Sc.D. Ralph C. Wands Mitchell R. Zavon, M.D. 1 TABLE OF CONTENTS Chemical Substances Page 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 UnderStudy............ H. Registered Trade Names............................... 2 9 34 35 36 37 39 45 46 50 51 51 54 56 Physical Agents Preface....................................................................... Threshold Limit Values Heat Stress............................................................. Ionizing Radiation.................................................. Lasers..................................................................... Microwaves............................................................ Noise....................................................................... Impulsive or Impact Noise.................................... Ultraviolet Radiation............................................. Notice of Intended Changes.................................... Notice of Intent: Lasers..................................................................... Light and Near-Infrared Radiation...................... Airborne Upper Sonic and Acoustic Radiation.. Radiofrequency/MicrowaveRadiation................ Agents Under Study.............................................. 59 60 67 68 78 79 81 82 85 85 85 88 89 93 sc 008199 1 - LAM009409 PREFACE CHEMICAL CONTAMINANTS 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, narcosjs, 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) Threshold Limit Value-Time Weighted Average (TLV-TWA) -- the time-weighted average concentra tion for a normal 8-hour workday and a 40-hour work week, to which nearly all workers may be repeatedly exposed, day after day, without adverse effect. b) Threshold Limit Value-Short Term Exposure Limit (TLV-STEL) -- the concentration to which workers can be exposed continuously for a short period of time without suffering from 1) irritation, 2) chronic or irreversible tissue change, or 3) narcosis of sufficient degree to increase the likelihood of acci dental injury, impair self-rescue or materially reduce work efficiency, and provided that the daily TLV-TWA also is not exceeded. It is not a separate independent exposure limit, rather it supplements the time-weight ed average (TWA) limit where there are recognized acute effects from a substance whose toxic effects are primarily of a chronic nature. STELs are recom mended only where toxic effects have been reported from high short-term exposures in either humans or animals. 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 time-weighted average is within the TLV. Exposures 3 SC 008200 LAM009410 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 warrented 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 work day. The relationship between threshold limit and per missible 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 inju ry to health depends upon a number of factors such as the nature' of the contaminant, whether very high concentrations -- even for short periods--produce acute poisoning, whether the effects are cumulative, the frequency with which high concentrations occur, and the duration of such periods. All-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 best controlled by a ceiling "C" limit that should not 4 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. "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. This at tention-calling designation is intended to suggest ap propriate measures for the prevention of cutaneous absorption so that the threshold limit is not invalid ated. 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 5 008201 SC LAA/I009417 Sc 08202 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 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 18 percent by volume under normal atmospheric pres sure (equivalent to a partial pressure, pOz of 135 mm Hg). Atmospheres deficient in O2 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. 6 Biologic Limit 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 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. 15: 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 irri tants, hemolytic chemicals, organic isocyanates, car bon 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 7 LAM009412 (e.g., employees of a single plant) are known to have potential exposure to possibly harmful concentra tions. Operational Guidelines: The ACGIH Board of Directors has adopted operational guidelines for the Chemical Agents TLV Committee. These guidelines prescribe: charge, authority, policies, membership, organization, and operating procedures. The policies include the appeals procedures. Copies of the guide lines document are available from the Publications Office at a cost of $5 per copy. 8 Substance [CAS #] ADOPTED VALUES TWA STEL ppm*11 mg/m^' ppm'11 mg/m361 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 [75-05-6] -- 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 acid [79-10-7]......... 10 30 ^Acrylonitrile [107-13-1] -- Skin.............................. (2, Ala) (4.5, Ala) Aid fin [309-00-2] -- Skin... -- 0.25 Ally! 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................ -- 10 Pyro powders................ -- 5 Welding fumes............... Soluble salts................. Alkyls (NOCt)................ -- -- -- 5 2 2 4-Aminodiphenyl [92-67-1] -- Skin.......................... -- Alb 2-Aminoethanol, see Ethanolamine 2-Aminopyridine [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 Ammonium chloride fume [12125-02-9]................. -- 10 150 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 20 Capital letters A, B, D & E refer to Appendices: C denotes ceiling limit. Footnotes (a thru f) see Page 34. `1982 Addition fSee Notices of Intended Changes. 9 SG LAM009413 Substance [CAS#] ADOPTED VALUES TWA STEL ppm"' mg/m3"' ppm"' mg/mjl" Ammonium sulfamate [7773-06-0]................... -- 10 -- n-Amyl acetate [628-63-7].. 100 530 150 sec-Amyl acetate [626-38-0] 125 670 150 Aniline [62-53-3] & homologues -- Skin...... 2 10 5 Anisidine ['29191-524] (o-, p-isomers) -- Skin......... 0.1 _0.5 Antimony [7440-36-0] & compounds, as Sb......... 0.5 Antimony trioxide [1327-33-9] Handling and use, as Sb . 0.5 Production..................... ANTU [86-884]................ Argon [7440-37-1 ]............ -- -- E A2 -- 0.3 -- ---- Arsenic [7440-38-2] & soluble compounds, as As................................. 0.2 Arsenic trioxide production [1327-53-3]................... Arsine [778442-1 ]............ 0.05 A2 0.2 _ -- Asbestos [1332-214], see MINERAL DUSTS........... Asphalt (petroleum) fumes Ala [8052424]................... 5 tAtrazine [1912-24-9].......... -- (10) -- Azinphos-methyl [86-50-0] -- Skin 0.2 Barium [7440-39-3], soluble compounds, as Ba................................. 0.5 Benomyl [17804-35-2]...... 0.8 10 1.3 Benzene [7143-2]............ 10, A2 30, A2 25, A2 'Benzidine [92-87-5] -- Skin -- Alb -- p-Benzoquinone, see Quinone Benzoyl peroxide [94-36-0]. 5_ Benzo(a)pyrene [50-32-8]... Benzyl chloride [10044-7].. -- 1 A2 -- 5-- Beryllium [744041-7]....... -- 0.002, A2 -- Biphenyl [92-524]............ 0.2 1.5 0.6 Bismuth telluride [1304-82-1]................... -- 10 -- 20 800. 800 20 ___ _ -- 0.9 -- -- Ala 10 -- 0.6 15 75, A2 Alb _ A2 -- -- 4 20 Capital letters A, B, 0 & E refer to Appendices: C denotes ceiling limit. Footnotes (a thru f) see Page 34. `1982 Addition tSee Notices of Intended Changes. 10 Substance [CAS #] ADOPTED VALUES TWA STEL ppm"' mg/m31" ppm"' mg/m3*" Se-doped ...................... -- 5 Borates, tetra, sodium salts [1303-964], Anhydrous..................... -- 1 Decahydrate.................. -- 5 Pentahydrate................. -- 1 Boron oxide [1303-86-2].... -- 10 Boron tribromide [10294-334]................. 1 10 Boron trifluoride [7637-07-2]................... Cl C3 Bromacil [31440-9].......... 1 10 Bromine [7726-95-6]......... 0.1 0.7 Bromine pentafluoride [7789-30-2].................. 0.1 0.7 Bromochloromethane, see Chlorobromomethane Bramoform [75-25-2] -- Skin............................. 0.5 5 Butadiene (1,3-butadiene) [106-99-0]..................... 1,000 2,200 Butane [106-97-8]............. 800 1,900 Butanethiol, see Butyl mercaptan 2-Butanone, see Methyl ethyl ketone (MEK)i 2-Butoxyethanol [111-76-2] -- Skin.......................... 25 120 n-Butyl acetate [123-864].. 150 710 sec-Butyl acetate [105464] 200 950 tert-Butyl acetate [540-88-5] 200 950 Butyl acrylate [141-32-2].... 10 55 n-Butyl alcohol [71-36-3] -- Skin............................. C 50 C 150 sec-Butyl alcohol [78-92-2]. 100 305 tert-Butyl alcohol [75-65-0]. 100 300 Butylamine [109-73-9] -- Skin.............................. C5 C 15 tert-Butyl chromate, as Cr03 [1189-85-1] --Skin...... -- C0.1 n-Butyl glycidyl ether (BGE) [2426-08-6]................... 25 135 n-Butyl lactate [138-22-7]... 5 25 Butyl mercaptan [109-79-5] 0.5 1.5 o-sec-Butylphenol [89-72-5] -- Skin.......................... 5 30 p-tert-Butyltoluene [98-51-1] 10 60 -- -- -- -- -- 3 -- 2 0.3 0.3 1,250 75 200 250 250 -- -- 150 150 -- -- -- -- 20 10 -- -- -- 20 30 -- 20 2 2 2,750 360 950 1,190 1,190 -- -- 455 450 -- -- -- -- 120 Capital letters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 34. 11 sc 008204 UMOO9474 Substance[CAS#] ADOPTED VALUES TWA STEL ppm' mg/m361 ppm"* mg/m3'" Cadmium [7440-43-9] Dust & salts, as Cd....... -- Cadmium oxide [1306-19-0] Fume, as Cd.................. -- $ Production, as Cd.......... -- 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] ...................... 2 Caprolactam [105-60-2] Dust.............................. __ Vapor............................ 5 Captafol [2425-06-1] -- Skin.............................. -- Captan [133-06-2].............. -- Carbary! [63-25-2]............ -- Carbofuran [1563-66-2]..... Carbon black [7440-444)]... -- -- Carbon dioxide [124-38-9].. 5,000 Carbon disulfide [75-15-0] -- Skin.......................... Carbon monoxide 10 [630-08-0]..................... 50 Carbon tetrabromide [558-13-4]..................... Carbon tetrachloride 0.1 [56-23-5]--Skin.......... 5, A2 Carbonyl chloride, see Phosgene Carbonyl fluoride [353-50-4]..................... 2 Catechol (Pyrocatechol) [120-80-9]..................... 5 Cellulose (paper fiber) [9004-34-6]............ Cesium hydroxide [21351-79-1]........... Chlordane [57-74-9] -- Skin....................... 0.05 0.2 C 0.05 (A2) D 20 0.5 1 5 2 D 12 3 1 __ 20 10 0.1 . __ 5-- 5 __ 0.1 __ 3.5 __ 9,000 15,000 30 __ 18 3 40 __ 15 10 7 27,000 __ 55 400 440 1.4 0.3 4 30, A2 20, A2 125, A2 55 20 -- D-- 2-- 0.5 -- 15 20 -- 2 Capital tetters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 34. tSee Notice of Intended Changes. 12 Substance [CAS#] ADOPTED VALUES TWA STEL ppm'1' mg/m3"1 ppm01 mg/m3*1 Chlorinated camphene [8001-35-2] --Skin...... -- 0.5 -- Chlorinated diphenyl oxide [55720-99-5]................. Chlorine [7782-50-5]........ __ 1 0.5 __ 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 C 3 __ 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 -- to-Chlorobenzylidene malononitrile [2698-41-1] -- Skin.......................... (0.05) (0.4) 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 Chlorodiphenyl (54% Chlorine) [11097-69-1] -- Skin.......................... 0.5 1-Chloro, 2, 3-epoxy-propane, see Epichlorohydrin 2-Chloroethanol, see Ethylene chlorohydrin Chloroethylene, see Vinyl chloride Chloroform [67-66-3]......... 10, A2 50, A2 50, A2 bis-Chloromethyl ether [542-68-1]..................... 0.001, 0.005, Ala Ala 1-Chloro-1-nitropropane [600-25-9]..................... 2 10 __ Chloropentafluoroethane [76-15-3]...................... 1,000 6,320 -- 1 2 9 0.9 -- -- -- -- 1,300 4,375 2 1 225, A2 __ -- Capital tetters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 34. tSee Notice of Intended Changes. 13 SC 008205 LAM009415 sc 008206 Substance [CAS#] ADOPTED VALUES TWA STEL ppmal mg/m3"' ppm"' mg/m3"' Chloropicrin [76-06-2]....... 0.1 0.7 /3-Chloroprene [126-99-6] -- Skin.......................... 10 45 o-Chlorostyrene [1331-28-8]................... 50 285 o-Chlorotoluene [95-49-8] -- Skin.......................... 50 250 2-Chloro- 6-(trichloromethyl) pyridine, see Nitrapyrin Chlorpyrifos [2921-88-2] -- Skin.............................. -- 0.2 Chromite ore processing (Chromate), as Cr........... -- 0.05,Ala Chromium [7440-47-3] Metal............................ -- 0.5 Soluble chromic, chromus salts, as Cr....... - 0.5 Chromium (II) compounds, as Cr............................ -- 0.5 Chromium (III) compounds, as Cr............................ - 0.5 Chromium (VI) compounds, asCr Water soluble................ -- 0.05 Certain water insoluble ... -- 0.05, Ala Chromyl chloride [14977-61-8]................. 0.025 0.15 Chrysene [218-01-9].......... A2 A2 Clopidol [2971-90-6].......... -- 10 Coal tar pitch volatiles [8007-45-2], as benzene solubles......................... -- 0.2, Ala tCobait [7440-484), as Co metal, dust & fume....... Copper [7440-50-8] - (0.1) Fume............................ -- 0.2 Ousts & mists, as Cu..... -- 1 Cotton dust, raw................ -- 0.2*" Cresol [1319-77-3], all isomeres -- Skin........... 5 22 Crotonaldehyde [123-73-9]. 2 6 Crufomate [299-86-5]....... - 5 Cumene [98-82-8] -- Skin.. 50 245 0.3 -- 75 75 -- -- -- -- -- -- -- -- -- -- -- -- __ -- ___ 6 -- 75 2 -- 430 375 0.6 -- -- -- -- __ -- -- -- 20 -- -- __ 2 0.6 ___ 18 20 365 Capital letters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 34. tSee Notice of Intended Changes, k) See p. 36. 14 Substance [CAS#] ADOPTED VALUES TWA STEL ppm"' mg/m3*' ppm01 mg/tn]'" 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 Cyclohexanol [108-93-0].... 50 200 Cyclohexanone [108-94-1].. 25 100 Cydohexene [110-83-8]..... 300 1,015 Cydohexylamine [108-91-8] -- Skin.......................... 10 40 Cydonite [121-824] -- Skin............................. _ 1.5 Cydopentadiene [542-92-7] 75 200 Cydopentane [287-92-3].... 600 1,720 Cyhexatin [13121-70-5]..... -- 5 2, 4-D [94-75-7] ............... -- 10 DDT (Dichlorodiphenyl- trichloroethane) [50-29-3]...................... 1 Decaborane [1770241-9] -- Skin.......................... 0.05 0.3 Demetron [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.............. Dibutyl phthalate [84-74-2]. 1 -- 5 5 Dichloroacetylene [7572-294]................... C0.1 C0.4 o-Dichlorobenzene [95-50-1] C 50 C300 p-Dichlorabenzene [10646-7]..................... 75 450 3, 3'-Dichlorobenzidene [91-94-11] --Skin......... __ A2 -- __ -- __ 375 -- 100 -- __ __ 150 900 -- -- 0.15 0.03 75 __ -- -- 4 2 -- __ -- 110 -- -- __ -- __ 1,300 -- 400 -- _ 3 400 2,580 10 20 3 0.9 0.3 360 0.3 -- -- 28 10 10 __ -- 675 A2 Capital letters A, B, D, & E refer to Appendices: C denotes ceiling limit. Footnotes (a thru f) see Page 34. 15 LAM009416 Substance [CAS #] ADOPTED VALUES TWA STB. ppm"' mg/m34' ppm"1 mg/m341 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-Dichloraethylene, see Vinylidene chloride 1, 2-Dichloroethylene [540-59-0]..................... 200 790 Dichloroethyl ether [111-44-4] -- Skin......... 5 30 Dichlorofluoromethane [75-43-4]...................... 10 40 Dichloromethane, see Methylene chloride 1, 1-Dichloro-1-nitroethane [594-72-9]..................... 2 10 1, 2-Dichloropropane, see Propylene dichloride Dichloropropene [542-75-6] -- Skin.......................... 1 5 2, 2-Dichloropropionic acid [75-99-0]...................... 1 6 Dichlorotetrafluoroethane [76-14-2]...................... 1,000 Dichlorvos [62-73-7] -- 7,000 Skin.............................. Dicrotophos [141-66-2] -- 0.1 1 Skin............................. Dicyclopentadiene [77-73-6] Dicyclopentadienyl iron 0.25 5 30 [102-54-5]..................... 10 Dietdrin [60-57-1] -- Skin .. __ 0.25 Diethanolamine [111-42-2]. 3 15 Diethylamine [109-89-7].... 10 30 Diethylaminoethanol [100-37-8] --Skin......... Diethylene triamine 10 50 [111-40-0] --Skin......... 1 4 Diethyl ether, see Ethyl ether Diethyl ketone [96-22-0].... Diethyl phthalate [84-66-2]. 200 -- 705 5 Difluorodibromomethane [75-61-6]...................... 100 860 1,250 250 250 10 10 10 1,250 0.3 __ __ __ 25 __ 150 6,200 0.4 1,010 1,000 60 60 50 8,750 3 __ 20 0.75 __ 75 10 1,290 Capital letters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 34. 16 Substance [CAS#] ADOPTED VALUES TWA STEL ppm01 mg/m34' ppm01 mg/m34' Diglycidyl ether (DGE) [2238-07-5]................... 0.1 0.5 -- -- Dihydroxybenzene, see Hydroquinone Diisobutyl ketone [108-83-8]..................... 25 150 -- -- Diisopropylamine [108-18-9] --Skin......... 5 20 -- -- Dimethoxymethane, see Methylal Dimethyl acetamide [127-19-5] --Skin......... 10 35 15 50 Dimethylamine [124-40-3].. 10 18 -- -- Dimethylaminobenzene, see Xylidene Dimethylaniline [121-69-7] (N, N-Dimethylaniline) -- Skin.................................... 5 25 10 50 Dimethylbenzene, see Xylene Dimethyl carbamyl chloride [79-44-7]........................... A2 A2 -- -- Dimethyl-1, 2-dibromo-2-dichloroethyl phosphate, see Naled Oimethylformamide [68-12-2] --Skin.......... 10 30 20 60 2, 6-Dimethyl-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] -- Skit.......................... 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 [73-34-2] -- Skin....... ...................... __ 0.2 __ __ Diphenyl, see Biphenyl Diphenylamine [122-39-4].. __ 10 -- 20 Diphenylmethane diisocyanate, see Methylene bisphenyl isocyanate Capital letters A. B. D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 34. 17 SC 008207 LAM009417 sc 008208 Substance [CAS #] ADOPTED VALUES TWA STEL ppm"' mg/m3*' ppm"' mg/m31" Dipropylene glycol methyl ether [34590-94-6] -- Skin.............................. 100 Dipropyl ketone [123-19-3]. 50 Diquat [85-00-7]................ -- Di-sec, octyl phthalate [117-81-7] (Di-2-ethyl- hexylphthalate).............. Disulfiram [97-77-6].......... -- Disulfoton [298-044]......... -- 2, 6-Ditert. butyl-p-cresol [128-37-0]..................... Diuron [330-54-1].............. -- Divinyl benzene [108-57-6]. 10 Emery [112-62-9].............. -- Endosulfan [115-29-7] -- Skin.............................. Endrin [72-20-8] --Skin.... -- Epichlorohydrin [106-89-8] -- Skin.......................... EPN [2104-64-53 --Skin ... 2 -- 1, 2-Epoxypropane, see Propylene oxide 2,3-Epoxy-1-propanol, see Glycidol Ethane [74-84-0]............... E Ethanethiol, see Ethyl mercaptan Ethanolamine [14143-5].... Ethion [563-12-2] --Skin .. 3 -- $2-Ethoxyethanol [110-80-5] -- Skin.......................... (50) 2-Ethoxyethyl acetate [111-15-9] --Skin......... (50) Ethyl acetate [141-78-6]..... 400 Ethyl acrylate [140-88-5] -- Skin.............................. 5 Ethyl alcohol (Ethanol) [46-17-5]...................... 1,000 Ethylamine [75-04-7]......... 10 Ethyl amyl ketone [41-85-5] 25 Ethyl benzene [100414]... 100 Ethyl bromide [74-964]..... 200 Ethyl butyl ketone [106-354]..................... 50 Ethyl chloride [75-00-3]..... 1,000 600 235 0.5 5 2 0.1 10 10 50 D 0.1 0.1 10 0.5 8 0.4 (185) (270) 1,400 20 1,900 18 130 435 890 230 2,600 150 -- -- -- -- -- -- -- -- 5 ' --- 6 -- (100) (100) -- 25 -- -- 125 250 75 1,250 900 -- 1 10 5 0.3 20 -- -- 20 0.3 0.3 20 2 15 -- (370) (540) -- 100 -- -- 545 1,110 345 3,250 Capital letters A, 8. D & E refer to Appendices: C denotes ceiling limit. Footnotes (a thru f] see Page 34. 4See Notice of Intended Changes. 18 Substance [CAS #] ADOPTED VALUES TWA STEL ppm' mg/m3*1 ppm* mg/m3* Ethylene [74-85-1]............. E ---- -- Ethylene chlorohydrin [107-07-31 --Skin......... Ethylenediamine [107-15-3] Cl 10 C 3 ___ 25 -- -- -- "Ethylene di bromide [106-93-4] --Skin......... A2 A2 -- -- Ethylene dichloride [107-06-21..................... 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...0..2..)...........(.0....1..)......(.0....0..5.)...........(0.3) Ethylene glycol methyl ether acetate, see 2-Methoxyethyl acetate Ethylene oxide [75-21-8].... (10) (20) -- -- Ethylene/mine [151-56-4] -- Skin.......................... 0.5 1-- -- Ethyl ether [60-29-7]....:.... 400 1,200 500 1,500 Ethyl formate [109-94-1].... 100 300 150 450 Ethylidene chloride, see 1,1-Dichloroethane Ethylidene nortomene [16219-75-3].................. Ethyl mercaptan [75-08-1].. C5 0.5 C 25 1 * N-Ethylmorpholine [100-74-3] -- Skin....... Ethyl silicate [78-10-4]..... Fensulfothion [115-90-2]... Fenthion [55-38-9]........... Ferbam [14484-64-1]........ 5 40 20 95 10 85 30 255 0.1 (0.1) (0.3) 10 20 Ferrovanadium dust [12604-58-9]................ 1 Fibrous d' glass dust......... 10 Fluorides, as F................. 2.5 Fluorine [778241-4].......... 2 Fluorotrichloromethane, see Trichlorofluoromethane Fonofos [944-22-9] -- Skin 0.1 T Formaldehyde [50-00-0].... (C 2) (C 3) Formamide [75-12-7]....... 20 30 Formic acid [64-18-6]...... 5 9 Furfural [98-01-1] --Skin . 2 8 -- 30 10 0.3 45 40 * Furftrryl alcohol [98-00-0] -- Skin......................... niintnii rnnnfi-fii.ai 10 40 15 60 Capital letters A, B. D & E refer to Appendices: C denotes ceiling limit. Footnotes (a thru 0 see Page 34. `1982 Addition. fSee Notice of Intended Changes. 19 LAM009418 Substance [CAS#] ADOPTED VALUES TWA STEL ppm01 mg/m36' ppm01 mg/m36' Germanium tetrahydride [7782-65-2]................... 0.2 0.6 0.6 Glass, fibrous or dust, see Fibrous glass dust Glutaraldehyde [111 -30-8].. C 0.2 C 0.7 -- Glycerin mist [56-81-5]...... -- D-- Glycidol [556-52-5]........... 25 75 100 Glycol monoethyl ether, see 2-Ethoxyethanol Graphite (Natural) [778242-5], see MINERAL DUSTS Graphite (Synthetic)........... Gypsum [1010144]......... Hafnium [7440-58-6]......... Helium [7440-59-7]........... -- -- -- E D-- D-- 0.5 -- ---- Heptachlor [7644-8] -- 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 -- Hexachlorocydopenta- diene [77474].............. 0.01 0.1 0.03 Hexachloroethane [67-72-1] -- Skin.......................... 10 100 -- Hexachloronaphthalene [1335-87-1] --Skin...... -- 0.2 -- Hexafluoroacetone [684-16-2]..................... 0.1 0.7 0.3 Hexamethyl 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 Li 42-92-/J..................... 50 300 -- Hexylene glycol [10741-5]. C 25 C 125 -- Hydrazine [302-01-2] -- Skin.............................. 0.1, A2 0.1, A2 Hydrogen [1333-74-0]....... E -- -- -- Hydrogenated terphenyls [92-944]...................... 0.5 5-- 1.8 -- -- 300 -- 20 1.5 -- 2 2,000 -- 0.3 -- 0.6 2 -- -- 3,600 -- -- -- -- -- Capital letters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 34. '1982 Addition. 20 Substance [CAS #] ADOPTED VALUES TWA STEL ppm"1 mg/m3'" ppm' mg/m]t" Hydrogen bromide [10035-10-6]................. 3 10 Hydrogen chloride [7647-01-1]................... C5 C7 Hydrogen cyanide [74-90-8] -- Skin.......................... CIO C 10 -- 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 [7783-064]................... 10 14 15 Hydroquinone [123-31 -9]... -- 2-- 4-Hydroxy4-methyl-2-pentanone, see Diacetone aiconoi 2-Hydroxypropyl acrylate [999-61-1] --Skin......... Indene [95-13-6]............... 0.5 10 3 45 15 Indium [7440-74-6] & compounds, as In.......... -- 0.1 -- Iodine [7553-56-2]............ C0.1 Iodoform [7547-8]........... 0.6 Cl -- 10 i Iron oxide fume (Fe^) [1309-37-1], as Fe......... B3 5-- * iron pentacarbonyl [1346340-6], as Fe....... Iron salts, soluble, as Fe.... Isoamyl acetate [123-92-2]. Isoamyl alcohol [123-51-3]. Isobutyl acetate [110-19-0]. Isobutyl alcohol [78-83-1 ].. 0.1 -- 100 100 150 50 0.8 0.2 1-- 525 125 360 125 700 187 150 75 Isooctyl alcohol [26952-21 -6]................. 50 270 -- Isophorone [78-59-1]......... C5 C 25 -- Isophorone diisocyanate -- Skin............................. 0.01 0.09 -- lsopropoxyethanol [109-59-1]..................... 25 105 75 Isopropyl acetate [108-214]..................... Isopropyl alcohol [67-63-0]. Isopropylamine [75-31-0]... 250 400 5 950 310 980 500 12 10 --" 0 0 21 4 70 0.3 -- 20 10 0.16 2 655 450 875 225 -- -- -- 320 1,18s 1,225 24 Capital letters A. 8, 0 & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 34. '1982 Addition. 21 - SC 008209 LAM009419 sc 008210 Substance [CAS #] ADOPTED VALUES TWA STEL ppm1" mg/m3*' ppm"' mg/m3" N-lsopropylanillne [643-28-7] -- Skin......... Isopropyl ether [108-20-3],. Isopropyl glycidyl ether [4016-14-2] (IGE).......... Kaolin............................... Ketene [463-51-4].............. Lead [7439-92-1], inorg., dusts & fumes, as Pb..... LLead arsenate [10102-48-4], as Pb...... 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]......... Magnesium oxide fume [1309-48-4]................... Malathion [121-75-5] -- Skin.............................. Maleic anhydride [108-31-6] Manganese [7439-96-5], as Mn Dust & compounds....... Fume............................ Manganese cyclopentadienyl tricarbonyl [12108-13-3], 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].... Methacrylicacid [79-41-4].. 2 10 250 1,050 50 240 --D 0.5 0.9 0.15 (0.15) _ 0.05, A2 --D -- 0.5 -- 0.025 1,000 -- 1,800 D 10 10 0.25 1 C5 --1 0.1 --1 D 0.01 _ 0.05 _ 0.1 15 60 20 70 5 310 75 -- 1.5 -- -- -- 1,250 -- -- -- -- _ 25 -- Capital letters A, B. D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 34. `1982 Addition. tSee Notice of Intended Changes. 20 1,320 360 20 3 0.45 (0.45) 20 1.5 -- 2,250 20 -- 3 0.3 -- 20 0.03 _ _ 100 -- 22 Substance[CAS#] ADOPTED VALUES TWA STEL ppm01 mg/m3" ppmal mg/m3" Methane [74-82-8]............ E -- Methanethiol, see Methyl mercaptan Methomyl [16752-77-5] -- Skin.............................. Methoxychlor [72-43-5]..... -- -- 2.5 10 42-Methoxyethanol [109-86-4]--Skin.......... (25) (80) 42-Methoxyethyi acetate [110-49-6] -- Skin......... (25) (120) *4-Methoxyphenol [150-76-5]..................... __ 5 Methyl acetate [79-20-9].... 200 610 Methyl acetylene [74-99-7]. 1,000 1,650 Methyl acetylene-propadiene mixture (MAPP)............ 1,000 1,800 Methyl acrylate [96-33-3] -- Skin.......................... 10 35 Methylaciylonitrile [126-98-7] --Skin......... 1 3 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 [591-78-6]..................... 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 Methylcydohexanol [25639-42-3]................. 50 235 o-Methylcyclohexanone [583-60-8] -- Skin......... 50 230 -- -- -- (35) (35) __ 250 1,250 1,250 __ 2 1,250 250 -- 100 1 15 __ 100 450 4 500 75 75 -- -- (120) (170) __ 760 2,040 2,250 __ 6 3,875 310 -- 465 5 60 __ 205 2,450 16 2,000 350 345 Capital letters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 34. 1982 Addition. 4See Notice of Intended Changes. 23 LAM009420 Substance [CAS #] ADOPTED VALUES TWA STEL ppm"` mg/m3<" ppm"1 mg/m3<" Methylcyclopentadienyl 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]...................... 100 360 4, 4'-Methylene bis (2-chlonoaniline) [101-14-4] --Skin......... 0.02, A2 0.22, A2 Methylene bis(4-cyclo- hexylisocyanate) [101-68-8]..................... C0.01 C0.11 4, 4-Methylene dianiline [101-77-9] --Skin......... 0.1 0.8 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 1ketone Methyl hydrazine [60-34-4] -- Skin.......................... C 0.2, C 0.35, 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] --Skin......... 25 100 Methyl isobutyl ketone [108-10-1]..................... 50 205 Methyl isocyanate [624-83-9] -- Skin......... Methyl isopropyl ketone 0.02 0.05 [563-80-4]..................... Methyl mercaptan [74-93-1 ] 200 0.5 705 1 Methyl methacrylate [80-62-6]...................... 100 410 500 0.5 300 150 5, A2 40 75 -- 125 0.6 1.5 1,700 4 885 375 30, A2 165 300 _ 510 Capital letters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 34. `1982 Addition. 24 Substance [CAS #] ADOPTED VALUES TWA STEL ppm01 mg/m36' ppm"1 mg/m36' Methyl parathion [298-00-0] -- Skin.......................... Methyl propyl ketone [107-87-9]..................... Methyl silicate [681 -84-5]... a-Methyl styrene [98-83-9]. Mevinphos [7786-34-7] -- Skin.............................. Molybdenum [7439-98-7], as Mo Soluble compounds....... Insoluble compounds..... Monocrotophos [6923-22-4]................... Morpholine [110-91-8] -- Skin.............................. Naled [300-76-5]............... Naphthalene [91-20-3]....... /3-Naphthylamine [91-59-8]. Neon [7440-01-9].............. Nickel carbonyl, as Ni......... Nickel [7440-02-0] Metal............................ Soluble compounds, as Ni................................. Nickel carbonyl [13463-39-3], as Ni....... Nickel sulfide roasting, fume & dust, as Ni......... Nicotine [54-11 -5] -- Skin.. Nitrapyrin [1929-82-4]....... Nitric acid [7697-37-2]...... Nitric oxide [10102-43-9]... * p-Nitroaniline [100-01 -6] -- Skin.............................. Nitrobenzene -- Skin......... p-Nitrochlorobenzene [98-95-3] --Skin.......... 4-Nitrodiphenyl [92-93-3]... Nitroethane [79-24-3]......... Nitrogen dioxide [10102-44-0]................. -- 200 1 50 0.01 -- -- -- 20 -- 10 -- E 0.05 -- -- 0.05 -- -- -- 2 25 -- 1 -- -- 100 3 0.2 -- 700 250 65 240 100 0.1 0.03 5 10 0.25 70 3 50 Alb -- 0.35 1 0.1 0.35 1, Ala 0.5 10 5 30 3 5 (D Alb 310 6 -- -- -- 30 -- 15 -- -- -- -- -- -- -- -- -- 4 35 -- 2 -- -- 150 5 0.6 875 30 485 0.3 10 20- -- 105 6 75 Alb -- -- -- 0.3 -- -- 1.5 20 10 45 -- 10 (2) Alb 465 10 Capital letters A, B. D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 34. *1982 Addition. $See Notice of Intended Changes. 25 sc 008211 LAM009421 Substance [CAS #] ADOPTED VALUES TWA STEL ppmal mg/m3*' ppm01 mg/m3i" Nitrogen trifluoride [7783-54-2]................... 10 30 15 45 t Nitroglycerin (NG) [55-63-0] -- Skin.......................... (0.02) (0.2) (0.05) (0.5) Nitromethane [75-52-5]..... 100 250 150 375 11 -Nitropropane [108-03-2].. 25 90 35 135 T2-Nitropropane [79-46-9]... (C 25, N-Nitrosodimethylamine A2) (C 90, A2) __ _ [62-75-9] (dimethylnitro- soamine) -- Skin........... A2 A2 'Nitrotoluene [99-08-1 ] -- Skin.............................. 2 11 _ _ Nitrotrichloromethane, see Chloropicrin Nonane [111-84-2]............ 200 1,050 250 1,300 Octactiioronaphthalene [2234-13-1] --Skin...... 0.1 0.3 Octane [111-65-9].............. 300 1,450 375 1,800 Oil mist, mineral................ -- 5" -- 10 Osmium tetroxide [20816-12-0], as Os...... 0.0002 Oxalic acid [144-62-7]....... -- 0.002 0.0006 1-- 0.006 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.............. Paratliion [56-38-2] -- Skin -- 0.1 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.......... Pentaeiythritol [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 [127-18-4]..................... 50 335 (-) (-) Capital letters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 34. '1982 Addition. tNOC = Not otherwise classified. tSee Notice of Intended Changes. 26 Substance [CAS #] ADOPTED VALUES TWA STEL ppma) mg/m3*' ppm"' mg/m3"' Perchloromethyl mercaptan [59442-3]..................... 0.1 Perchloryl fluoride [7616-94-6]................... 3 Phenol [108-95-2] --Skin.. 5 Phenothiazine [92-84-2] -- Skin.............................. N-Phenyl-beta-naphthyl- amine [135-88-6]........... A2 p-Phenylene diamine [106-50-3] --Skin......... _ Phenyl ether [101-34-8], vapor............................ 1 Phenylethylene, see Styrene, monomer 'Phenyl glycidyl ether (PGE) [122-60-1]..................... 1 fPhenylhydrazine [100-63-0] -- Skin.......................... Phenyl mercaptan (5) [108-98-5]..................... 0.5 Phenylphosphine [638-21-1]..................... C 0.05 Phorate [298-02-2] -- Skin. -- Phosdrin, see Mevinphos Phosgene [7544-5]........... 0.1 Phosphine [3803-51-2]...... 0.3 Phosphoric acid [7664-38-2].................. __ Phosphorus [7723-14-0] (yellow)........................ __ * Phosphorus oxychloride [10026-13-8]................. 0.1 Phosphorus pentachtoride [10026-13-8]................. 0.1 Phosphorus pentasulfide [1314-80-3].................. __ 'Phosphorus trichloride [7719-12-2].................. 0.2 Phthalic anhydride [8544-9]...................... 1 m-Phthalodinitrile [626-17-5]..................... __ Picloram [1918-02-1]......... -- 0.8 14 19 5 A2 0.1 7 6 (20) 2 C 0.25 0.05 0.4 0.4 1 0.1 0.6 1 1 1.5 6 5 10 -- 6 10 _ _ 2 (10) __ __ -- __ 1 __ __ 0.5 __ __ 0.5 4 __ -- -- 28 38 10 _ 14 (45) __ 0.2 __ 1 3 0.3 3 3 3 24 __ 20 Capital letters A, B, 0 & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru 0 see Page 34. "1982 Addition. $See Notice of Intended Changes. 27 SC 008212 LAM009422 Substance [CAS #] ADOPTED VALUES TWA STEL ppm"' mg/m3'" ppmal mg/m31" Picric acid [88-89-1] -- Skin.............................. 0.1 Pindone [83-26-1]............. -- 0.1 'Piperazine dihydrochloride [142-64-3]..................... 5 2-Pivalyl-1,3-indandione, see Pindone Plaster of Paris................. -- 0 Platinum [7440-06-4] Metal............................ 1 Soluble salts, as Pt......... -- 0.002 Polychlorobiphenyls, see Chlorodiphenyls Polytetrafluoraethylene decomposition products.. -- B1 Potassium hydroxide [1310-58-3]................... C2 Propane [74-98-6]............. E -- Propane sultone [1120-71-4]................... A2 A2 Propargyl alcohol [107-19-7] -- Skin 12 /J-Propiolactone [57-57-8].. 0.5, A2 1.5, A2 Propionic acid [79-09-4].... 10 30 Propoxur [114-26-1].......... -- 0.5 n-Propyl acetate [109-60-4] 200 840 Propyl alcohol [71-23-8] -- Skin.............................. 200 500 n-Propyl nitrate [627-13-4]. Propylene [115-07-1]......... 25 E 105 -- Propylene dichloride [78-87-5]....................... 75 350 tPropylene glycol dinitrate [642343-4] (PGDN) -- Skin...................'.......... (0.02) (0.1) Propylene glycol mono- methyl ether [107-98-2].. 100 360 {Propylene imine [75-55-8] -- Skin.......................... Propylene oxide [75-56-9].. (2) 20 (5) 50 Propyne, see Methyl acetylene Pyrethrum [8003-34-7]...... 5 Pyridine [110-86-1]........... 5 15 Quinone [106-514]........... 0.1 0.4 RDX, see Cydonite -- _ -- -- 3 1, A2 15 -- 250 250 40 -- 110 (0.05) 150 -- 10 0.3 0.3 0.3 20 -- B1 -- 6 3, A2 45 2 1,050 625 470 -- 510 (0.3) 540 -- 10 30 1 Capital letters A, B, D 4 E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 34. '1962 Addition. tSee Notice of Intended Changes. 28 ADOPTED VALUES Substance TWA STEL [CAS #] ppm0' mg/m3"' ppm"1 mg/m361 Resorcinol [10846-3]....... 10 45 20 Rhodium [7440-16-6] * Metal............................ { Soluble salts, as Rh....... __ 1 -- (0.001) __ -- Ronnel [299-84-3]............ -- 10 -- Rosin core solder pyrolysis products, as formaldehyde................ 0.1 Rotenone (commercial) [83-794]...................... Rouge............................... __ -- 5 __ D-- Rubber solvent (Naphtha)... 400 1,600 -- Selenium compounds [778249-2], as Se......... __ 0.2 __ Selenium hexafluoride [7783-79-1], as Se......... 0.05 0.2 __ Sesone [136-78-7]............ -- 10 -- Silane, see Silicon tetrahydride Silicon [7440-21-3]........... Silicon carbide [409-21-2].. __ -- D __ D-- {Silicon tetrahydride [7803-62-5].................. (0.5) (0.7) (D Silver [7440-224], 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].................. __ C 2 __ Sodium metabisulfite [7681-574]................... Starch [9005-84-9]............ Stibine [7803-52-3]........... -- 0.1 5 __ D 0.5 0.3 'Stoddard solvent [805241-3].................. Strychnine [57-24-9].......... 100 -- 525 200 0.15 ' -- Styrene, monomer [10042-5]..................... 50 215 100 90 __ (0.003) -- 0.3 10 20 -- __ __ 20 20 20 (1.5) -- -- -- __ 0.15 __ __ 20 1.5 1,050 0.45 425 Capital letters A, B. 0 4 E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 34. *1982 Addition. tSee Notice of Intended Changes. 29 SC 008213 LAM009423 Substance [CAS#] ADOPTED VALUES TWA STEL ppm"' mg/m3"' ppm01 mg/m3*' Subtilisins [1395-21-7] (Proteolytic enzymes as 100% pure crystalline enzyme)......................... --C0.00006"" Sucrose [57-50-1 ].............. -- D Sulfotep [3689-24-5] -- Skin.............................. 0.2 Sulfur dioxide [7446-09-5].. 2 5 Sulfur hexafluoride [2551-62-4]................... 1,000 6,000 Sulfuric acid [7864-93-9]... -- 1 Sulfur monochloride [10025-67-9]................. 1 6 Sulfur pentafluoride [5714-22-7]................... 0.025 0.25 Sulfur tetrafluoride [7783-60-0]................... 0.1 0.4 Sulfuryl fluoride [2699-79-8].................. 5 20 Systox, see Demeton 2, 4, 5-T [93-76-5]............ Tantalum [7440-25-7]....... -- 10 5 TEDP, see Sulfotep Tellurium & compounds [13494-80-9], as Te...... 0.1 Tellurium hexafluoride [7783-80-4], asTe......... 0.02 0.2 Temephos [3383-96-8]...... -- 10 7EPP [107-49-3] -- Skin.... 0.004 0.05 Terphenyls [92-94-4]......... C 0.5 C5 1, i, 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. (5) (35) Tetrachloroethylene, see Perchloroethylene Tetrachloromethane, see Carbon tetrachloride Tetrachloronaphthalene [1335-88-2].................. -- 2 Tetraethyl lead [78-00-2], as Pb -- Skin................ O.IOO^ Tetrahydrofuran [109-99-9], 200 590 -- 5 1,250 -- 3 0.075 0.3 10 -- -- 0.01 -- 625 625 (10) 250 20 0.6 10 7,500 -- 18 0.75 1 40 20 10 20 0.2 -- 5,210 5,210 (70) 4 0.3 735 Capital letters A, B, D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 34. m) See Page 36. 30 Substance [CAS #1 ADOPTED VALUES TWA STEL ppm"' mg/m34' ppm1" mg/m3"' Tetramethyl lead [75-74-1 ], as Pb--Skin................ Tetramethyl succinonitrile [3333-52-6] -- Skin...... 0.150 0.5 3 Tetranitromethane [509-14-8]..................... Tetrasodium pyrophosphate [7722-88-5].................. 1 __ 8 5 Tettyl [479-45-8] (2, 4, 6-trinitrophenylmethylnitramine) -- Skin. Thallium [7440-28-0] 1.5 Soluble compounds, as T1 -- Skin...................... 4, 4'-Thiobis(6-tert. butyl- m-cresol) [96-69-5]....... Thiogiycolic acid [68-11-1]. Thiram [137-26-8]............ __ 1 -- 0.1 10 5 5 Tin [7440-31-5] * Metal............................ * Oxide & inorganic compounds, except SnOn, as Sn............................ Organic compounds, as Sn -- Skin..................... __ __ 2 2 0.1 Titanium dioxide [13463-67-7], as Ti....... __ o-Tolidine [119-93-7]......... A2 Toluene [108-88-3] (toluol) -- Skin.......................... 100 tToluene-2, 4-diisocyanate (TDI) [584-84-9]............ (C 0.02) $o-Toluidine [95-53-4] -- D A2 375 (C 0.14) Skin............................. (2) Toxaphene, see Chlorinated camphene (9) Tributyl phosphate [126-73-8]..................... 0.2 2.5 Trichloroacetic acid [76-03-9]...................... 1 5 1, 2, 4-Trichlorobenzene [120-82-1]..................... 5 40 1,1,1-Trichloroethane, see Mefiyl chloroform 2 __ -- __ -- -- -- __ __ -- 150 -- __ 0.4 -- __ 0.5 9 -- -- 3.0 20 -- 10 4 4 0.2 20 -- 560 -- __ 5 -- -- Capital letters A, B. D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 34. "1982 Addition tSee Notices of Intended Changes. 31 SC 008214 LAM009424 Substance [CAS #] ADOPTED VALUES TWA STEL ppm01 mg/m3*' ppm01 mg/m3*' 1,1, 2-Trichloroethane [79-00-5] --Skin.......... 10 45 ^Trichloroethylene [79-01-6], 50 270 'Trichlorofluoromethane [75-69-4]...................... C 1,000 C 5,600 Trichloromethane, see Chloroform Trichloronaphthalene [1321-65-9]................... -- 5 Trichloronitromethane, see Chloropicrin 1,2,3-Trichloropropane [96-18-4]...................... 50 300 1,1, 2-Trichloro-1, 2, 2- trifluoroethane [76-13-1]. 1,000 7,600 Tricydohexyltin hydroxide, see Cyhexatin TTriethylamine [121-44-8].... (25) (100) Trifluorobromomethane [75-63-8]...................... 1,000 6,100 Trimellitic anhydride [552-30-7]..................... 0.005 0.04 Trimethyl benzene [25551-13-7]................. 25 125 'Trimethyl phosphite [121-45-9]..................... 2 10 2,4,6-Trinitrophenol, see Picric acid 2, 4, 6-Trinitrophenyl-methylnitramine, see Tetryl *2,4,6-Trinitrotoluene (TNT) [118-96-7] --Skin -- 0.5 Triorthocresyl phosphate [78-30-8] ...................... -- 0.1 Triphenyl amine [603-34-9], Triphenyl phosphate -- 5 [115-86-6]..................... -- 3 Tungsten [7440-33-7], as W Insoluble compounds..... 5 Soluble compounds....... -- 1 Turpentine [8006-64-2]...... Uranium (natural) 100 560 [7440-61-1], Soluble & in soluble compounds, as U 0.2 Valeraldehyde [110-62-3]... 50 175 20 (150) -- -- 75 1,250 (40) 1,200 -- 35 5 -- -- -- -- -- 150 -- 90 (805) -- 10 450 9,500 (160) 7,300 -- 170 25 3 0.3 -- 6 10 3 840 0.6 -- Capital letters A, B. D & E refer to Appendices; C denotes ceiling limit. Footnotes (a thru f) see Page 34. *1982 Addition fSee Notices of Intended Changes. 32 Substance ADOPTED VALUES TWA STEL [CAS#] ppm-' mg/m3** ppm-1 mg/m3*' 'Vanadium, as V205 [1314-62-1], respirable dust & fume........................ Vegetable oil mists............ Vinyl acetate [108-05-4].......... -- -- 10 0.05 D 30 Vinyl benzene, see Styrene Vinyl bromide [593-60-2]... 5, A2 Vinyl chloride [75-01-4]..... 5, Ala 20, A2 10, Ala Vinyl cyanide, see Acrylonitrile Vinyl cyclohexene dioxide [106-87-6]..................... TVinylidene chloride [75-5-4] Vinyl toluene [25013-15-4]. 10, A2 (10) 50 60, A2 (40) 240 VM & P Naphtha [8030-30-6]...................... Warfarin [81-81-2]............. Welding fumes (N0C+)...... 300 1,350 -- 0.1 -- 5, B2 Wood dust (certain hard woods as beech & oak)... Softwood..................... -- -- 1 5 Xylene [1330-20-7] (o-, m-, p-isomers) -- Skin......... 100 435 m-Xylene a, a'-diamine [1477-55-0]................... -- C0.1 'Xylidene [1300-73-8] -- Skin.............................. Yttrium [7440-65-5].......... 2 -- 10 1 Zinc chloride fume [7646-85-7].................. - Zinc chromate [13530-65-9], as Cr....... - 0.05, A2 Zinc oxide [1314-13-2] Fume............................ Dust.............................. Zinc stearate [557-05-1]..... -- -- -- 5 D D Zirconium compounds [7440-67-2], as Zr........ - 20 (20) 100 400 150 60 (80) 485 1,800 0.3 B2 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 34. '1982 Addition. 4See Notice of Intended Changes. 33 sc 008215 LAM009425 sc 008216 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 jim 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 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. Maximutn 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. 34 Substance SIUCA, S/0 2 MINERAL DUSTS Crystalline Quartz [1480-60-7] TLV in mppcf1": 300*' % 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 Cristobalite............ Use one-half the value calculated . [14464-46-1] from the count or mass formulae for quartz. Tridymite............... Use one-half the value calculated [15468-32-3] from formulae for quartz. Silica, fused [60676-86-0]......... Use quartz formulae. Tripoli.................... Use respirable"' mass quartz for- [1317-95-9] mula %Amorphous [7631-86-9]..........................(20 mppcf0') SIUCATES (< 1 % quartz) Asbestos Amosite [12172-73-5] 0.5 fiber > 5/xm/cc, Ala Chrysotile [12001-29-5].......... 2 fibers > 5^m/cc, Ala Crocidolite [12001-28-4].......... 0.2 fiber > 5p.m/cc, Ala Other forms............... 2 fibers > 5/^m/cc, Ala Graphite (natural) [7782-42-5]............... Mica [12001-26-2]........ Mineral wool fiber.......... Perlite............................. Portland Cement............ Soapstone...................... 15 mppcf 20 mppcf 10 mg/m3 30 mppcf 30 mppcf 20 mppcf $Talc (nonasbestiform) [14807-96-6].............. (20 mppcf) f:Talc (fibrous), (use As bestos limit.) tSee Notice of Intended Changes. 35 LAM009426 COAL DUST 2 mg/m3 (respirable dust fraction < 5% quartz). If > 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. 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 characteristics: Aerodynamic Diameter (pan) (unit density sphere) s2 2.5 3.5 5.0 10 % passing selector 90 75 50 25 0 j) 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 the 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 con trast illumination. m) Based on "high volume" sampling. n) "Respirable" dust as defined by the British Medical Research Council Criteria,(1) and as sampled by a de vice producing equivalent results.'2' 36 (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. 3/^:133(1970). NOTICE OF INTENDED CHANGES (for 1982) 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 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 TWA STEL [CAS#] ppm01 mg/m3*' ppm111 mg/m31" tAcrylonitrile [107-13-1] -- Skin.............................. Atrazine [1912-24-9].......... Cadmium oxide production. 2, A2 -- -- 4.5, A2 5 0.05 -- -- o-Chlorobenzylidene malononitrile [2698-41-1] C 0.05 C 0.4 -- Chloromethyl methyl ether [107-30-2]..................... Cobalt carbonyl, as Co....... A2 -- A2 -- 0.1 -- Cobalt hydrocarbonyl [16842-03-8], as Co...... __ 0.1 -- Cobalt metal, dust & fume [7440-48-4], as Co......... __ 0.05 -- Enflurane [13838-16-9]...... 75 575 -- f2-Ethoxyethanol [110-80-5] -- Skin.......................... 5 19 -- 12-Ethoxyethyl acetate [111-15-9] --Skin......... 5 27 -- t Ethylene glycol [107-21-1], particulate DELETE, see Appendix G Ethylene glycol dinitrate (EGDN) [628-96-6] -- Skin.............................. 0.05 0.3 0.1 -- -- -- -- -- -- -- 0.1 -- -- -- 0.6 Capital letters A, B, D & E refer to Appendices; C denotes ceiling limit. f1982 Revision or Addition. 37 LAM009427 sc 008218 Substance TWA [CAS #] ppm mg/m3 STEL ppm01 mg/uP1 t Ethylene oxide [75-21-8].... 1,A2 2, A2 [Fenamiphos [22224-92-6] -- Skin.......................... -- 0.1 Fenthion [55-38-9]............ -- 0.2 [Formaldehyde [50-00-0]..... C1,A2 C1.5, A2 -- [Grain dust......................... -- 4-- Halothane [151-67-7]......... 50 400 -- Lead arsenate [10102-48-4], as Pb3(As04)2................ -- 0.15 __ [2-Methoxyethanol [109-86-4] --Skin......... 5 16 [2-Methoxyethyl acetate [110-49-6] --Skin [Metribuzin [21087-64-9].... --5 24 5 __ p-Nitrochlorobenzene [100-00-5] --Skin......... 0.5 3 Nitroglycerin (NG) [55-63-0] -- Skin.......................... 0.05 0.5 0.1 2-Nitroprapane [79-46-9]... 10, A2 35, A2 20, A2 [Perchloroethylene [127-18-4] -- Skin......... 50 335 200 Persulfates, alkali metal, as S2O8............................. 2' Phenylhydrazine [100-63-0] -- Skin.......................... 5, A2 20, A2 10, A2 Propylene glycol dinitrate (PGDN) [6423-434] -- Skin............................. 0.05 0.3 0.1 Propylene imine [75-55-8] -- Skin.......................... 2, A2 5, A2 fRhodium, Insoluble compounds, as Rh......... 1 Soluble compounds, as Rh................................ 0.01 Silicon tetrahydride (Silane) [7803-62-5].................. 5 7 [Sulprofos [3540043-2]..... -- 1 __ Toluene-2,4-diisocyanate (TDI) [584-84-9]............ 0.005 0.04 0.02 [o-Toluidine [95-534] -- Skin............................. 2, A2 9, A2 [Trichloroethylene [79-01-6], 50 270 200 Triethylamine [12144-8].... 10 40 15 Trimethylamine [75-50-3]... 10 40 15 [Vinylidine chloride [75-354]...................... 5 20 20 0.45 _ 1 70, A2 1,340 45, A2 0.6 __ 0.15 1,080 60 60 80 Capital letters A. B, D & E refer to Appendices; C denotes ceiling limit. f1982 Revision or Addition. 38 NOTICE OF INTENDED CHANGES MINERAL DUSTS Substance TLV Diatomaceous earth, natural [60676-86-0], Silica, amorphous........ [7631-86-9] Talc (containing no libers) [14807-96-6] Talc (fiber-containing)...... 1.5 mg/m3, Respirable dust 6 mg/m3, Total dust (all sampled sizes) 3 mg/m3, Respirable dust (< 5 /xm) 15mppcf or 2 mg/m3, Respirable dust 2 fibers/cc, > 5 /xm in length 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 (1 b). 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.............. bis (Chloromethyl) ether Chromite ore processing (chromate)............... Chromium (VI), certain water insoluble compounds............... 2 ppm 0.5 fiber > 5/xm/cc 2 fibers > 5/xm/cc 0.2 fiber > 5/xm/cc 2 fibers > 5/xm/cc 0.001 ppm 0.05 mg/m3, as Cr 0.05 mg/m3, as Cr "See Notice of Intended Changes. 39 LAM009428 sc 008219 Coal tar pitch volatiles .. Nickel sulfide roasting, fume & dust.............. Vinyl chloride............... 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 t Benzidine -- Skin ** Chloromethyl methyl ether /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 Cadmium oxide production Carbon tetrachloride -- Skin Chloroform Chloromethyl methyl ether 2 ppm -- -- -- 10 ppm -- 2.0 /xg/m3 -- 5 ppm 10 ppm -- 'Cigarette smoking can enhance the incidence of respiratory cancers from this or others of these substances or processes. f1982 Addition, jl 982 Adoption. "See Notice of Intended Changes. 40 Chromates of lead and zinc, as Cr 0.05 mg/m3 Chrysene ------- 3, 3'-Dichlorobenzidine--Skin ------ Dimethylcarbamyl chloride ------ 1, 1-Dimethyl hydrazine-- Skin 0.5ppm Dimethyl sulfate -- Skin 0.1 ppm Ethylene dibromide -- Skin ------ Ethylene oxide 1 ppm + Formaldehyde C 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 ------ Phenylhydrazine -- Skin 5 ppm Propane sultone beta-Propiolactone ------0.5 ppm Propylene imine -- Skin 2 ppm $ o-Tolidine ------- t 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. 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 fl 982 Addition, jl 982 Adoption. 41 LAM009429 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 range finding 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 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 42 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 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 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; 43 008220 LAM009430 Examples: 7, 12-Dimethylbenz(a)anthra cene -- skin tumors @ 0.120.8 mg T.D. in four weeks Benzo(a)pyrene, mice 12 mj, 3X/wk for 18 mos. T.D. 2.6 mg, 90.9% skin tumors OR 1c. 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, s 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. 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 A3a and A3c 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. 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 44 species by any one of three routes of adminis tration at the following prescribed dosages and conditions; la. Respiratory. Elicit cancer from (1) dosages greater than 10 mg/m3 (or equivalent ppm) via the respiratory tract in 6- 7-hour, daily 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, @ 15 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 B1 Polytetrafluoroethylene' decomposition products. Thermal decomposition of the fluorocarbon chain in air leads to the formation of oxidized products containing carbon, fluorine and oxygen. Because 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 termination of the toxicity of the products, but air concentrations should be minimal. B2 Welding Fumes -- Total Particulate (NOC)t- TLV, 5mg/m3 Trade Names: Algoflon. Ruon, Halon, Teflon, Tetran. tNot otherwise classified (N0C). 45 008221 LAM009431 sc 008222 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 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, _2i . _C2 Ti Tz _Cj T. 46 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 1A.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 + or + etc.^j 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. CAA 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. 47 LAM009432 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.) =i Example No. lA.a.: Air contains 400 ppm of acetone (TLV = 1000 ppm) 150 ppm of sec-butyl acetate (TLV = 200 ppm) and 100 ppm of 2-butanone (TLV = 200 ppm) Atmospheric concentration of mix ture = 400 + 150 + 100 = 650 ppm of mixture 400 150 1000 + 200 100 200 = 0.4 + 0.75 + 0.5 = 1.65 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 airvapor mixture, and also to fractional concen trations of this mixture; e.g., 112 the TLV; 1110 the TLV; 2 x the TLV; 10 x the TLV; etc.) TLV of mixture = ____________________ 1_____________________ fq , ft> , , fn TLV,, TLV,, TLVC ' ' TLV,, 48 Example No. 1: 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 = 0.18 ppm 20% perchloroethylene: TLV = 100 ppm or 670 mg/m3 1 mg/m3 s 0.15 ppm TLV of Mixture = 0.5 1600 1 0.3 1900 0^ 670 1 0.00031 + 0.00016 + 0.00030 1 = 1300 mg/m3 0.00077 of this mixture 50% or (1300) (0.5) = 650 mg/m3 is heptane 30% or (1300) (0.3) = 390 mg/m3 is methyl chloro form 20% or (1300) (0.2) = 260 mg/m3 is perchloroethylene These values can be converted to ppm as follows: heptane: 650 mg/m3 x 0.25 = 162 ppm methyl chloroform: 390 mg/m3 x 0.18 = 70 ppm perchloroethylene: 260 mg/m3 x 0.15 = 39 ppm TLV of mixture = 162 + 70 + 39 = 271 ppm, or 1300 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). 0.15 -^=0.7 1 Threshold limit is not exceeded. IB. TLV for Mixtures of Mineral Dusts. For mixtures of biologically active mineral dusts the general formula for mixtures may be used. For mixture containing 80% nonasbestifomn talc and 20% quartz, the TLV for 100% of the mixture is given by: 49 sc 008223 LAM009433 TLV 1 -- =9mppcf M 20 U TLV of nonasbestiform talc (pure) = 20 mppcf TLV of quartz (pure) = 300 100 + 10 2 ? mppcf Essentially the same result will be obtained if the limit of the more (most) toxic component is used provided the effects are additive. In the above ex ample the limit for 20% quartz is 10 mppcf. For another mixture of 25% quartz, 25% amor phous silica and 50% talc: 25% quartz -- TLV (pure) = 2.7 mppcf 25% amorphous silica -- TLV (pure) = 20 mppcf 50% talc TLV (pure) = 20 mppcf TLV __________1_ ----= 8 mppcf 0.25 | 0,25 U-0 2.7 20 20 The limit for 25% quartz approximates 9 mppcf. APPENDIX D Some Nuisance Particulates0' TLV, 30 mppcf or 10 mg/m3 of total dust < 1% quartz, or, 5 mg/m3 respirable dust o-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%. 50 Acetylene Argon Ethane Ethylene APPENDIX E Some Simple Asphyxiants"1 Helium Hydrogen Methane Neon p) As defined on pg. 6. Propane Propylene 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/m3.1'1 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 ap plication 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 >tm or 1.5 x 10TM1 cm. This assumption is, of course, quite arbitrary since the mmd of all dust clouds is quite variable, depending on many independent parameters, such as source of dust, age of 51 sc 008224 LAM009434 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). 3. Calculation: a) vol. per particle: 4/3 it r3; r = 0.75 x 10-> cm = 4/3 7T (0.75 x 10-)3 = 1.77 x 10-12 cm3 b) wt. per particle = vol. x density = 1.77 x 10-12 crna x 2.5 x 103 mg/cm3 = 4.425 x io~9 mg/particle c) 1 particle/ft.3 = 35.5 part./m3 (since 35.5 cu ft = 1 cu m.) 10s part./ft3 = mppcf = 35.5 x 10 part./m3 wt. of 1 mppcf = 35.5 x 10 part./m3 x 4.425 x io-9 mg/part. 1 mppcf = 0.157 mg/m3 or 6.37 mppcf s i mg/m3 or approximately 6 mpccf = 1 mg/m3. Reference 1. Jacobson, M. and T. F. Tomb: Relationship Between Gravimetric Re spirable Oust Concentration and Midget Impinger Number Concentra tion. Am. Ind. Hyg. AsSoc. J. 28:554 (Nov.-Dee. 1967). 52 DENSITY p(g/cm3) RATIO MMD D(Mm) IS u 13 -- 12 11 10 ~ 9 -j 6-- 7-- 6-- 0036 33 .005 -- .01 -- .03 -- .2 p- 10 9 8 7 6 S 4 .4 .5 3 1 3 22 3 4 5- 10 -- 2 20 30 40 1 50 100 -- 1 200 300 400 .C 500 5 Figure 1 -- Ratio of Particle Count -- mppcf to Respir able Mass Concentration -- mg/m3 (as function of density and mmd)+ ^Prepared by P. E. Caplan and R. J. Smith 53 SC 008225 LAM009435 Table 1 Equivalent TLVs in mppcf and mg/m3 (Respirable Mass) for Mineral Dustst Substance Threshold Limit Value Count Resp. Mass Total Mass mppcf mq/m3 mq/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) 1010 (10) (10) (6) (0.3) tAssuming that the mass median diameter is 1.5/xm and density is 2.5 g/cm3. 'Unless otherwise specified, respirable mass is presumed to equal ap 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 * 50% total mass. APPENDIX G Chemical Substances and Other Issues UnderStudy1 Chemical Substances Acetonitrile Acetophenone Acetyl acetone Allyl chloride Aluminum oxide Asbestos Bismuth telluride Carbonyl fluoride Cellulose Chlorinated camphene (60%) Chlorinated naphthalenes Chlorine bis-Chloromethyl ether Copper dust & fume Diatomaceous earth 54 Diethylenetriamine Emery Epichlorohydrin Ethyl chloride Ethylene dichloride Graphite Hexafluoroacetone Isocyantes Jet fuel Methylenedianiline Methyl methacrylate Methyl tertiary butyl ether Nickel, metal & soluble compounds Nitrous oxide Osmium tetroxide "Other"glycol ethers Piperizine Propylene chloride Propylene oxide Silica, all forms Silicon carbide Silicon tetrahydride (Silane) Styrene, monomer 2,3,7,8-Tetrachlorodibenzop-dioxin (TCDD) Tetrachloronaphthalene Tin hydride 1,2,3-Trichloropropane Trimellitic anhydride m-Xylene 2,2'-diamine (MXDA, meta-metaxylenediamine) Other Issues Dual vapor and particulate TLVs.*2 Role of Biological Exposure Indices relative to air borne contaminant TLVs.2 Role of STELs and Excursion limits.2 STELs will be used for specific health effects and Excursion limits will be used for substances without a specific STEL. Should mppcf values be retained (Appendix F)? Should welding fume value (not otherwise classified, NOC) be retained or should specific analytical determina tions be made for metals and other compounds and these values be compared to specific TLVs? 'Informatinn, data especially, and comments are solicited to assist the committee in its deliberations and in the development of draft documents. 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 ol the American Conference of Governmental Industrial Hygienists, Volume 4, Transactions olthe 1982 Meeting (available late 1982). 55 . . sc 008226 LAM009436 sc 008227 APPENDIX H Registered Trade Names Trade Name Generic Name Abate Ammate Azodrin Baygon Baytex Bidrin Bolstar Butyl Cellosolve Cellosolve acetate Coyden Crag herbicide Dasanit Delnav Dibrom Difolatan Disyston Dursban Dyfonate 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 Cyhexab'n Metribuzin Carbaryl Polytetrafluoroethylene Phorate Endosulfan Picloram Dinitolmide 56 TLVs Threshold Limit Values for Physical Agents Adopted by ACGIH for 1982 LAIVI009437 sc 008228 1982 TLV PHYSICAL AGENTS COMMITTEE Herbert H. Jones, NIOSH (Retired) --Chairman Peter A. Breysse, University of Washington Thomas Cummings, Ontario Ministry of Labour Irving H. Davis, Michigan Dept, of Public Health Zory R. Glaser, Ph.D., Bureau of 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 David H. Sliney, USAEHA COL Robert T. Wangemann, USA Thomas K. Wilkinson, National Institutes of Health CONSULTANTS Gerald V. Coles William E. Murray, Wordie H. Parr, Ph.D. 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 Hy gienists 6500 Glenway Ave., Bldg. D-5 Cincinnati, OH 45211: (513)661-7861 58 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. 59 LAM009438 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.11-z> 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 v/hen their deep body tempera ture exceeds 38.0C. 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 : ' 60 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 25% Work -- 75% Rest, Each hour 31.4 29.4 27.9 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. 61 SC 008229 LAM009439 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 Minaret.'3-" TABLE 2 Assessment of Work Load19' Average values of metabolic rate during different activities. 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/min Hand work light 0.4 0.2-1.2 heavy 0.9 Work witli 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 62 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/minII. 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 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. 63 SC 008230 LAM009440 (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, (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 lite rature'5'81 may be utilized also. When this method is used the permissible heat exposure limit can be determined by Figure 1. 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: Av. M = (Mi) x (tQ + (Mz) x (t2) + ...+ (M,,) x (t,,) (tl) + (t2) +....+ (t,,) Where Mi M2, M,, are estimated or measured metabo lic rates for the various activities of the worker during the total time period, ti, t2, t,, are the elapsed times in minutes spent at the corresponding metabolic rate as determined by a time study. The time-weighted average WBGT shall be deter mined by the equation: Av. WBGT = (WBGTi) x (ti) + (WBGTz) x tz + + (WBGT,,) x (t,,) (ti) + (t2) + . . . + (t,,) where WBGTi, WBGT2, WBGT,, are calculated values of WBGT for the various work and rest areas occu 64 pied during total time periods, ti, tz, t,, are the elapsed times in minutes spent in the corresponding areas which are determined by a time study. Where expo sure to hot environmental conditions is continuous for several hours or the entire work day, the timeweighted averages shall be calculated as hourly timeweighted average i.e., ti+tz + ... + tn=60 minutes. Where the exposure is intermittent, the time-weighted averages shall be calculated as two-hour time-weight ed averages, i.e., ti +12 + ... + 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 counted as rest time when additional rest allowance must be given because of high environmental temper atures. Btu/hr Rate of Work Figure 1 -- Permissible Heat Exposure Threshold Limit Value 65 WBGT 008231 LAM009441 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% (1g 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. References: 1. Health Factors Involved in Working Under Conditions ol Heal Stress. WHO Technical Report Series No. 412 (1969). 2. Dukes-Dobos, F. N. and A. Henschel: Development of Permissible Heal Exposure Limits for Occupational Work. ASHRAE Journal 15(9):57-62 (Sept. 1973). 66 3. Minard, D.: Prevention of Heat Casualties in Marine Corps Recruits. Period ot 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 Institue. Bethesda, M0 (Feb. 21. 1961). Published in Military Medicine 126(44) :261-272 (April 1961). 4. Minard, 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. Astrand, Per-Olof and Kaare Rodahl: Textbook ot 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 tor Physical Work. Research Progress Report No. 30. Purdue Farm Cardiac Project, Agricultural Experiment Sta tion, West Lafayette, IN (1961). 8. Durnin, 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: Oer Kalorienbedarf bie Gewerblicher Arbeit. Arbeitsphysiol. 14:166 (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.*1'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. References: 1. Basic Radiation Protection Criteria. NCRP Report No. 39 (January 15, 1971). 2. Maximum Permissible Body Burdens and Maximum Permissible Con centrations of Radionuclides in Air and in Water tor Occupational Ex posure. Nabonal Bureau of Standards Handbook 69. (June 5,1959), with Addendum 1 (August 1963). Available as NCRP Report No. 22. 67 SC 008232 LAM009442 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. LASERS 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 (C^) as shown in Figure 2. Between 1049 nm and 1400 nm, the TLV has been increased by a factor (CJ of five. For certain exposure times at wavelengths be tween 550 nm and 700 nm, correction factor (Cs) must be applied. The TLVs for skin exposure are given in Table 6. The TLVs are to be increased by a factor (CA) 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. 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 irra- 68 diance 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 fora 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: (ars,)= Standard (pulse nr) n where: n = number of pulses in train t = duration of a single pulse in the train Standard (nr) = protection standard of one pulse having a duration equal to nr sec onds. Figure 2 -- TLV correction factor for X = 700 - 1400 nm' 'For K = 700 - 1049 nm, CA = 10toOMa -7MI1 For X = 1050 - 1400 nm, C,, = 5 69 . 008233 SC LAM009443  TABLE 4 Threshold Limit Value for Direct Ocular Exposures (Intrabeam Viewing) from a Laser Beam C,, = 1 tor \ = 400 to 549 nm; C,, = 101" " 11,k - 550 l>" lor- Ki " = 550 to 700 nm. T, = 10 s for K = 400 to 549 nm; T, = 10 x 10 <" ,k '1for K = 550 to 700 n. SC 008234 e0 s? CmO "O 03 CO 8o 1w is * o . oo ooo ocomocnocomoco cocoTrcor--r-cMT3-coi~T--c\i-<rco X :C o =cos co ii O CM CO O CM CO EEEEEEEEEE EEE c c e c e c c c: c e c c e c O CO 'O' m to r-- CO CM *3* o co o o o o CM CM CO CO CO CO CO CO CO CO O CD >> 70 Eo u N Eo e oI E EE o' u I is E M cj *--> CO o E o ,,X to CO. T-. o_E -r- CO. T- E> X o_ T- 3m. O o m T CO X m ^ cJ-' o7 C\J o m t- ; < o !x O X 2. r- o . CO 1 X ~. " x I o v T^ T-- -w o- T T-- " T- f-- T-- <* oS"0^2 " o O o > CO "i o o `"xpp0srx;r2 o o o 9 o o -o oI co ** I Ee : Ee o r- Ec o ph- EC TJin Ec o o r- E c o r*- E e r- c cE Ee Ee _E = cco oci3.. - TJ- O' O' TT rt t-- T- O' O o^^ o o o o o o o o *- +* o o Ec tr) : co Ec Ec: Ec Ec EcEc oo <f >o j> mio -o* EE11EE Oc Oc tOoU)C03.. : K t" t-- f** r* o o3 <> =3 CQ QC U! E o -5 71 LAM009444 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 = 700 to 1400 nm.\ ? " E; E'"L I L-, CO 0 CO I 'V m 1 k. ^ "I E> x Eco o a, g03 ^i>>-jcoo*5 O^ UCOxf rZ ra o ^ ^ ^ i CO t~ CM CO CM CM " CO o CO OoT CO o I *" X . 'X oo?h^s?"o aI |a 'O+*+*+o** |a ` ~O n-> aI oooo, -ooooo eeeseeIIc S<=<oo=oo="Oo=Oo=OocroroToorToj- Ep- O" N LO fs. N Is* T-- T-- T-* -- OOOOO^OOOOO EccE cE cEcEcEcEcEcEE oOoOoOmOOmOoOsoOsoOso-rT-. o oQ < CD OC OC 72 SC 008235 Eo ' . --* i: ^i 1CLr-. )^ r og i CO CM y- o CO X* CO 1 I I <- ICD < Vo> C._O . 0 O O CO o Q*- A a i O a oooo > 'I o. OO' T1--r Ec: Ec : E o o3 oO 03 Q. CO r<<o ~)-o-ij cc cc c*c 73 LAM009445 TABLE 7 Limiting Angle to Extended Source Which May Be Used for Applying Extended Source TLVs Exposure Duration(s) 1010101010101010101.0 10 102 103 10" Angle a (mrad) 8.0 5.4 3.7 2.5 1.7 2.2 3.6 5.7 9.2 15 24 24 24 24 EXPOSURE OURATION (S ) Figure 3a -- TLV for infrabeam (direct) viewing of CW laser beam (400-1400 nm) 74 75 LAM009446 SC 008236 EXPOSURE DURATION Is) Figure 4a -- TLV for laser exposure of skin and eyes for far-in frared radiation (wave-lengths greater than 1.4 Mm)- Figure 5a -- TLV for extended sources or diffuse reflections of laser radiation (400-700 nm). Figure 4b -- TLV for CW laser exposure of skin and eyes for far-infrared radiation (wave-lengths greater than 1.4 nm). 76 Figure 5b -- TLV for extended sources or diffuse reflections of laser radiation (400-1400 nm). 77 SC 008237 LAM009447 TLV CORRECTION FACTOR SC 008238 Figure 6 -- Multiplicative correction factor for repetitively pulsed lasers having pulse durations less than 10~5 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. "MICROWAVES These Threshold Limit Values refer to microwave energy in the frequency range of 300 MHz to 300 GHz and represent conditions under which it is believed that nearly all workers may be repeatedly exposed without adverse effect. Under conditions of moderate to severe heat stress, the recommended values may need to be reduced.11' Therefore, these values should be used as guides in the control of exposure to microwave en ergy and should not be regarded as a fine line be tween safe and dangerous levels. Recommended Values: The Threshold Limit Value for occupational expo sure to microwave energy, where power density or "See Notice of Intended Changes. 78 field intensity is known and exposure time is con trolled, is as follows: 1. For exposure to continuous wave (CW) sources, the power density level shall not exceed 10 mil liwatts per square centimeter (mW/cm2) for contin uous exposure, and the total exposure time shall be limited to an 8-hour workday. This power den sity is approximately equivalent to a free-space electric field strength of 200 volts-per-meter rms (V/m) and a free-space magnetic field strength of 0.5 ampere-per-meter rms (A/m). 2. Exposures to CW power density levels greater than 10 mW/cm2 are permissible up to a maximum of 25 mW/cm2 based upon an average energy density of 1 milliwatt-hour per square centimeter (mWh/cm2) averaged over any 0.1 hour period. For example, at 25 mW/cm2, the permissible exposure duration is approximately 2.4 minutes in any 0.1 hour period. 3. For repetitively pulsed microwave sources, the average field strength or power density is calculat ed by multiplying the peak-pulse value by the duty cycle. The duty cycle is equal to the pulse duration in seconds times the pulse repetition rate in Hertz. Exposure during an 8-hour workday shall not ex ceed the following values which are averaged over any 0.1 hour period: Power Density 10 mW/cm2 Energy Density 1 mWh/cm2 Mean Squared Electric Field Strength 40,000 V2/m2 Mean Squared Magnetic Field Strength 0.25 A2/m2 4. Exposure is not permissible in CW or repetitively pulsed fields with an average power density in ex cess of 25 mW/cm2 or approximate equivalent free-space field strengths of 300 V/m or0.75 A/m. Reference: 1. Mumford, W. W.: Heat Stress Due to R. F. Radiation. Proceedings of IEEE 57(2): 171-178 (Feb. 1969). 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-S3.6- 79 LAM009448 I Table 8 Threshold Limit Values of noise that contributes to the sound level meter reading at slow response. Duration per Day Hours Sound Level dBAt 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 16 80 than the individual effect of each. If the sum of the 8 85 following fractions: 4 2 i1 1/2 1/4 1/8 90 95 100 105 110 115* i i Ci _Ca + . . Ti Ta T,, exceeds unity, then, the mixed exposure should be considered to exceed the threshold limit value, Ci in 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 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, SI.4 (1971) Type S2A, and posures of 80 dBA or greater shall be used in the above calculations. set to use the A-weighted network with slow meter response. IMPULSIVE OR IMPACT NOISE "No exposure to continuous or intermittent in excess of 115 dBA It is recommended that exposure to impulsive or 1969) at 500, 1000, and 2000 Hz, and the limits which are given have been established to prevent a hearing impact noise shall not exceed the limits listed in Table 9 or taken from Figure 7. No exposures in ex- loss in excess of this level.*01 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, S1.4 (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 "In 1979, the American Academy of Ophthalmology and Otolargyngology (AA00) included 3000 hzin their hearing impairment formula. 80 NUMBER OF IMPULSES OR IMPACTS PER DAY (N) Figure 7 -- Threshold Limit Values for Impulse/Impact Noise. SC 008239 LAM009449 sc 008240 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 *iPa 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.111 These values should be used as guides in the control of ex posure to continuous sources where the exposure duration shall not 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 Laser TLVs. 82 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 10 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: Ee/r = X Ex Sx AX where: Ee// = effective irradiance relative to a monochromat ic source at 270 nm in W/cm2 (J/s/cm2) Ex = spectral irradiance in W/cm2/nm Sx = relative spectral effectiveness (unitless) AX = band width in nanometers Figure 8 -- Threshold Limit Values for Ultraviolet Radiation 83 LAM009450 TABLE 10 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 Sx 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 11 Permissible Ultraviolet Exposures Duration of Exposure Per Day 8 hrs....... 4 hrs........ 2 hrs....... 1 hr......... 30 min.... 15 min.... 10 min.... 5 min...... 1 min...... 30 sec.... 10 sec.... 1 sec....... 0.5 sec... 0.1 sec... Effective Irradiance, E,,ff (^W/cm2) ....... ....... ........ 0.1 0.2 0.4 ........ ........ ........ ........ 0.H 1.7 3.3 5 ........ 10 ........ 50 ....... 100 ........ 300 ........ 3,000 ....... 6,000 ........ 30,000 84 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 Et/r in W/cm2. The expo sure time may also be determined using Table 11 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 ef a/, Eds. Univ. of Tokyo Press, Tokyo, Japan (1974). NOTICE OF INTENDED CHANGES (1982) 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 ESTABUSH THRESHOLD LIMIT VALUES LASERS It is proposed that the following footnote be added to Table 7 (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 85 - SC 008241 LA1V1009451 sc 008242 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 12 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 *|Q{(450-m0) 0.001 0.001 .. 0.001 Bum 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 -j Qt<700--A>/505| 0.2 86 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 12) should not exceed: 1400 Vi SLxRiAXiil/at 400 (1)* where L* is in W cnr2 sr*1 and t is the viewing du ration (or pulse duration if the lamp is pulsed) lim ited to 1 /is 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 light source weighted against the blue-light hazard function Bx (Table 12) should not exceed: 1400 ^ Lx t Bx A\ s 100 Jem"2 sr1 (t si 104s) (3a) 1400 Lx Bx AX S 10"2 Wcm-2 sr' (t > 10*s) (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/cm"2 sr' in the blue spectral region, the permissible exposure duration tmax in seconds is simply: tmax = 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 (E(blue)] should not exceed: 87 LAM009452 1400 Ex t Bn AX 10 mJ cm-* (t S lO1 s) (5a) 1400 ^ Ex Bx AX S 1/iW cm2 (t a 10" s) (5b) For a source where the blue light weighted irradiance E (blue) exceeds 1 /iW crrr2 is the maxi mum permissible exposure duration tmax in sec onds is: tmu = 10mJ 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 mWcrrr2. 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 J 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 13 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 levels. 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 Die 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 sVj/(cmJ sr), and for formda (7) k, = 1 W rad/(cm' sr). 88 TABLE 13 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 uPa 80 80 80 105 110 115 115 115 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 14 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 9. 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 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 14. 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 = -^|^- where: E2 is in volts squared (V2) per meter squared (m2). 89 SC 008243 LAM009453 PD in mW/cm2 =37.7H2 where: 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 14 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 14 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. 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/cm2, 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 burn 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. 90 203 ca o co 8_ x ^ hr- ^ lo LO co C\J CD t) ^ o csi cviooLo CD 2 O CD ,< 03 o x Xo r-- Orr*-*-- Orh--- o f*. Sf-- CO CO CO CO co o o r~ o o r- o T- 03 T-- -T- . a: ^ n: _ o o <z> o CO co o o o 1-- o co 0 oO o o ^'='=*=0 91 tmW/cm* = milliwatts per centimeter squared ='I Irequency in MHz F sc 008244 LAM009454 sc 008245 7. No measurement should be made within 5 cm of any object. 8. All exposures should be limited to a maximum (peak) electric field intensity of 100 kV/m. o 5 PHYSICAL AGENTS UNDER STUDY The Physical Agents Committee pf 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 O o 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. 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