Document RpMKrN67jwDRR5V43GMO2BYgV
To
Frnm
Tkodicti amd Chstuca/l
PUT IT IN WRITING
Date
28 April 1978
R- C. LietzauSubject INDUSTRIAL HYGIENE PROGRAM
C. J. Smith______________________
CALVERT CITY
A review o the industrial hygiene work which has been completed and a tentative projection of the work to be completed with target dates and man-hour requirements is shown below.
In general the guidelines which we are following require that we sample every job which is connected with each^toxic chemical using eight hour personnel samples for a period of five consecutive days. The subsequent date at which a particular job must be resampled for the toxic chemical is based upon the average analyses reported during the initial weeks sampling. That is, it must be sampled monthly if the published TLV is exceeded or in three months if the level is greater than one-half the TLV and less than the TLV or it must be sampled yearly if the average level is below one-half the TLV. We aTe sampling foT only one day on resamples. However, another five conse cutive days of sampling is warranted if a process change is made which could change the concentration of any toxic chemical.
If the industrial hygiene work proceeds as projected, we will have completed the testing for 30 of the 45 chemicals on tiur list or 67% by January, 1979. However, if the projected hours for methods development is close to correct, we will only have completed ^ 534 of the total hours of methods development work.
CJS:ry
Attachment
cc: R. W. McGinnis M. H. Stermon
S/ju&L
SMITH
AP00043606
ACETYLENICS
1. Acetone'
POLYVINYL ALCOHOL
1. MeOH a. 3rd. floor b. 400 line c. Maint. d. Misc. plant
2. MeAc a. 3rd. floor b. Misc. plant
POLYVINYL CHLORIDE
1. VCM 2. TCE 3. DMF
INDUSTRIAL HYGIENE PROGRAM
Personnel sampling has been conducted for the following;
Hours ppm Method
TLV Development
Initial Date
Sampled
Ave. Result
ppm
Sampling Analyses Hours Required
Next
Sampling Date
Re-sampling $ Analyses
Hours
Required
1000
120
Feb., 1978
<1
40 Feb., 1979
]2
200 80 Jan., 1978
80
200 Jan., 1978 1085
Monthly
8
200
Jan., 1978
148
Apr., 1978
4
200
Jan., 1978
124
Apr., 1978
8
200
Jan., 1978
24
Jan., 1979
20
200 80 Jan., 1978
80
200
Jan., 1978
362
Monthly
8
200
--
Jan., 1978
16
-- Jan., 1979
20
1
160
Apr., 1975
1.5
100 25 Mar., 1978 <1
10 80 Mar., 1978 <.3
96 Monthly 16 Mar., 1979 50 Mar., 1979
96 16
12
AP00043607
CD
EMULSION
1. Formaldehyde 2. Ammonia t 3. VAc.
Hours ppm Method TLV Development
Initial
Date Sampled
Ave. Result
ppm
Sampling fT Analyses Hours Required
Next
Samp]ing Date
Re-Sampling 5 Analyses
Ilou rs Rcquired
2
24
Mar., 1978
<1
40 Mar., 1979
12
25
24
Mar., 1978
1
40 Mar., 1979
12
10 80 Apr., 1978 0.96 40 Apr., 1979 12
ACETYLENICS
1 . IPE 2. MEK ' 3. MIBK ! 4. 2-Et. Hex.` 5. n-Butyr . 6 . Isophorone iv. 7 . Propargyl Ale. 8. Ethylene Gly. 9. Methyl Amyl Ket. 10. MB 11. MP 12. Surf 61 13. Hexynol 14. EO 15. DH 16. DO 17. Surf 104 18. KOH 19. DMF ; 20. Aprol 148
^Estimated hours.
Personnel sampling will be conducted for the following:
250 200 100
-
5 1 100 100 -
-
2 mg/ui^ 10 -
40 40 40 40 80* 60* 100*
100* 80*
100* 100*
100*
100* 100* 100* 100* 100*
60* 80
100*
May, May, June,
June, Aug., Oct.,
1978 1978 1978
1978 1978 1978
May, 1978 May, 1978
(2)
40 40 40 40 40 40 40 40 40 40 40 40
40 40 40 40 40 25 40 40
12 12 12
12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 16 12
AP00043608
AP00043609
POLYVINYL ALCOHOL
1. VAc 2. Acetic Acid 3. Acetaldehyde
Hours ppm Method TLV Development
Initial Date
Sampled
Ave. Result
PP3*
Sampling f* Analyses Hours Required
Next
Sampling Date
Re-Sumplin, Analyses
Hours Required
10 80 June, 1978
10
100*
Oct., 1978
100 40* Dec., 1978
40 40 40
12 12 12
POLYVINYL CHLORIDE
1. VAc 2. 2-Et. Hex. 3. Methyl Chloride
10 80 July, 1978 - 40 July, 1978
- 60* Nov., 1978
40 40 `40
12 12 12
EMULSION
1. VCM ~
1 Available- May, June, 1978
2. DMF ?
10 Available Sept., 1978
3. MeOH '
200 Available Sept., 1978
4. ' Maleic Anhydride ^ .25 me/m3
100*
Dec., 1978***
5. Acrylamide ^
.3 mg/m3
100*
Dec., 1978***
6. Acrylic Acid
- 100*
7. Butyl Acrylate
- 100*
8. Methacrylic Acid
100*
20
40 40 40
40 40 40
40
12
12 12 12 12 12 12 12
UTILITIES
1. Particulates 2. SO 2
10 rag/m3** 16
July, 1978
5 Drager Tube: July, 1978
40 8
12 8
"Estimated hours. **May vary with silica content. ***Provided a new polarograph is available by November, 1978.
C3)
.1
TLVs Threshold Limit Values
for Chemical Substances
and Physical Agents
in the Workroom Environment
with Intended Changes
for 1978
AP00043610
Copyright 1978 by American Conference of Govern mental Industrial Hygienists.
The American Conference of Governmental Industrial Hygienists will welcome requests for permission to re publish or reprint these Threshold Limit Values. Re quests for such permission should be directed to the Executive Secretary. P.0. Box 1937, Cincinnati, Ohio 45201.
PRICE EACH
1-49.......................................................................... $1.50 50-199...................................................................... 1.25 200-999...,.............................................................. 1.10 1000-4999.................................................................... 75 5000 or more.................................................................85
Documentation of the Threshold Umit Values for Sub stances In Workroom Air. * A separate companion piece to the Chemical TLVs is issued by ACGIH under this title. This publication gives the pertinent scientific Information and data with reference to literature sources that were used to base each limit. Each documentation also con tains a statement defining the type of response against which the limit is safeguarding the worker. For a better understanding of the TLVs it is essential that the Docu mentation be consulted when the TLVs are being used.
Information concerning the availability of copies of the Documentation ot the Threshold Limit Values for Substances in Workroom Air should be directed to the Executive Secretary, ACGIH (third edition, fourth print ing. 1978, $20,00),
TLVs Threshold Umit Values
for Chemical Substances in Workroom Air Adopted by
ACGIH for 1978
AP00043611
197* TLV AIRBORNE CONTAMINANTS
COMMITTEE Hervey 8. Elkins, Ph.D., Chairman
Charles E. Adkins Maiy 0. Amdur, Ph.D. Hector P. Blejer, M.D. Paul E. Caplan, P.E., M.P.H, Paul Gross, M.D. James W. Hammond John W. Knauber, M.P.H. Jesse Lleberman, P.E. Trent R. Lewis, Ph.D. Keith R. Long, Ph.D. Frederick T. McDermott Floyd A. Madsen Waiter W. Melvin, Jr., M.D., Sc.D. Leonard D, Pagnotto, Secretary Ronald S. Ratney Meier Schneider, P.E., CJ.H, Richard D. Stewart, M.D. Herbert E.Stoklnger, Ph.D. Vera F. Thomas, Ph.D.
William D. Wagner Elizabeth K. Weisburger, Ph.D. David H. Wegman, M.D.
CONSULTANTS
E. Mastromatteo, M.D. James F. Morgan Marshall Steinberg, Ph. D. Theodore R. Torketson, Sc.D. Ralph C. Wands Mitchell R. Zavon, M.D.
Any comments or questions regarding these limits should be addressed to:
Executive Secretary American Coniwenceot Governmental
industrial Hygienists CPi.nOc.inBnoaxti1O9H3745201: (513) 825-0312
| I
> 1 ! || I
TABLE OF CONTENTS
Chemical Sufaalancea
Page
Preface........................................................................ 2
Threshold Limit Values and Short Term Exposure
limits..................................................................... 9
Radioactivity.............................................................. 31
Mineral Dusts......................................
31
Nuisance Particulatas................................................ 32
Notice of Intended Changes...................................... 33
Appendices
A. Carcinogens.........................................................36
B. Substances of Variable Composition............ 43
C. Mixtures: Calculation of TLVs....................... 44
D. Excursions
Time-Weighted Average............................. 48
Peak Concentrations.................................. 49
E. Nuisance Particulates..................................... 50
F. Asphyxiants..............................
50
G. Conversion of Particle Count toMass............ 50
Physical Agents
Preface........................................................................
Threshold Limil Values Heat Stress.............................................................
ionizing Radiation.................................................. Lasers.......................................... Microwaves...........................................................
Noise...................................................................... impulsive or Impact Noise....................................
Ultraviolet Radiation...................................... Notice of Intended Changes......................................
Notice of intent: Light and Near-Infrared Radiation.........................
Airborne Upper Sonic and Acoustic Radiation..... Agents Under Study...............................................
55
56 65 65 81 82 83 86 89
90 93 94
\ \>
AP00043612
jmsk
Mk
borne Contaminants (Penna. Dept, of Kith., Chapter 4,
Art. 432. Rev. Jan. 25, 1968). (4) OSHA Occupational
PREFACE
Safety and Health Standards, 40 FR 23073, May 28,
CHEMICAL CONTAMINANTS
1975. (5) NIOSH criteria tor recommended standards for
Threshold limit values refer to airborne concentra tions of substances and represent conditions under which It is believed that nearly all workers may be repea tedly exposed day after day without adverse effect. Be
occupational exposure to specific substances. The TWASTEL should not be used as engineering design criterion
or considered as an emergency exposure level (EEL). c) Threshold Limit Value-Ceiling (TLV-C) -- the con
centration that should not be exceeded even instantan
cause of wide variation in individual susceptibility, how
eously.
ever, a small percentaoe of workers may experience
?
For some substances, e.o., irritant gases, only one
discomfort from some substances at concentrations at
category, the TLV-Celling, may be relevant. For other
or below the threshold limit; a smaller percentage may
substances, either two or three categories may be rele
be affected more seriously by aggravation of a pre-exist
vant, depending upon their physiologic action. II is Im
ing condition or by development of an occupational ill
portant to observe that if any one of these three TLVs is
ness.
exceeded, a potential hazard from that substance is pre
Tests are available (J. Occup. Med. 15; 564, 1973;
sumed to exist.
Ann. N.Y. Acad. Sci., 151, Art. 2: 96B, 1668) that may be used to detect those individuals hypersusceptlbie to a variety of industrial chemicals (respiratory irritants, he
The TLV-TWA should be used as guides In the con trol of health hazards and should not be used as fine lines between safe and dangerous concentrations.
molytic chemicals, organic Isocyanates, carbon disul
Time-weighted averages permit excursions above the
fide).
limit provided they are compensated by equivalent ex
Three categories of Threshold Limit Values (TLVs)
are specified herein, as follows; a) Threshold Limit Value-Time Weighted Average
cursions below the limit during the workday. In some instances ft may be permissible to calculate the average concentration tor a workweek rather than for a workday.
(TLV-TWA) -- the time-weighted average concentration
for a normal 8-hour workday or 40-hour workweek, to which nearly all workers may be repeatedly exposed, day
The degree of permissible excursion is related to the magnitude of the threshold limit value of a particular substance as given in Appendix D. The relationship be
after day, without adverse effect.
tween threshold limit and permissible excursion Is a rule
b) Threshold Limit Value-Short Term Exposure Limit
of thumb and In certain cases may not apply. The
(TLV-STEl)--the maximal concentration to which
amount by which threshold limits may be exceeded for
workers can be exposed for a period up to 15 minutes continuously without suffering from 1) irritation, 2)
Short periods without injury to health depends upon a number of factors such as the nature of the contamin
chronic or irreversible tissue change, or 3) narcosis of
ant, whether very high concentrations -- even for short
sufficient degree to increase accident proneness, impair
self-rescue, or materially reduce work efficiency, provid ed that no more than four excursions per day are permu
periods -- produce acute poisoning, whether the effects are cumulative, the frequency with which high concen
trations occur, and the duration of such periods. All-fac
ted, with at least 60 minutes between exposure periods,
tors must be taken into consideration in arriving at a
and provided that the dally TLV-TWA also is not exceed
decision as to whether a hazardous condition exists.
ed. The STEL should be considered a maximal allowable
Threshold limits are based on the best available infor
concentration, or ceiling, not to be exceeded at any time
mation from industrial experience, from experimental
during the 16-minute excursion period. STELs are based
human and animat studies, and, when possible, from a
on one or more of the following criteria; (1) Adopted
combination of the three. The basis on which the values
TLVs including those with a "C" or "ceiling" limit. (2)
are established may differ from substance to substance;
TWA-TLV Excursion Factors listed in Appendix D. (3)
protection against impairment of health may be a guid
Pennsylvania Short-Term Limits for Exposure to Air-
ing factor for some, whereas reasonable freedom from
23
;
\
AP00043613
irritation, narcosis, nuisance or other forms of stress may form the basis for others.
The amount and nature of the information available for establishing a TLV varies from substance to sub stance; consequently, the precision of the estimated TLV is also subject to variation and the latestDocumentation should be consulted in order to assess the extent of the
data available fora given substance. The committee holds to the opinion that limits based
on physical irritation should be considered no less bind ing than those based on physical impairment. There is increasing evidence that physical irritation may initiate, promote or accelerate physical impairment through In teraction with other chemical or biologic agents.
in spite of the fact that serious injury is not believed likely as a result of exposure to the threshold limit con centrations, the best practice is to maintain concentra tions Of all atmospheric contaminants as low as Is prac
tical. These limits are intended for use in the practice of
industrial hygiene and should be interpreted and applied 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 nuisances, (3) in estimating the toxic potential of continuous, uninterrupt ed exposures or other extended work periods, (4) as proof or disproof of an existing disease or physical con dition, or (5) for adoption by countries whose working conditions differ from those in the United States of America and where substances and processes differ.
Ceiling vs Time-Weighted Average limits. Although the time-wetohted average concentration provides the most satisfactory, practical way of monitoring airborne agents for compliance with the limits, there are certain substances lor which it Is inappropriate, in the tatter group are substances which ate predominantly fast act
ing and whose threshold limit is more appropriately based on this particular response. Substances with this type of response are best controlled by a ceiling "C" limit that should not be exceeded. It is implicit in these definitions that the manner of sampling to determine noncompliance with the limits for each group must differ; a single brief sample, that is applicable to a "C" limit, Is not appropriate to the time-weighted limit; here,
4
a sufficient number ol samples are needed to permit a time-weighted average concentration throughout a com plete cycle of operations or throughout the work shift.
Whereas the ceiling limit places a definite boundary 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. The magnitude of these excursions may be pegged to the magnitude of the threshold limit by an appropriate factor shown in Appendix 0. It should be noted that the same factors are used by the Committee in determining 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 toe potential contribution to the overall exposure by the cutaneous route including mucous membranes and eye, either by airborne, or more particularly, by direct contact with the substance. Vehicles can alter skin absorption. This attention-calling designation is intended to suggest appropriate measures for the prevention of cutaneous absorption so that the threshold limit is not invalidated.
Mixtures. Special consideration should be given also to the application of the TLVs in assessing the health hazards which may be associated with exposure to mix tures of two or more substances. A brief discussion of basic considerations Involved in developing threshold limit values tor mixtures, and methods for their develop ment, amplified by specific examples are given in Ap pendix C.
Nuisance Particulates. in contrast to fibrogenic dusts which cause scar tissue to be formed In lungs when in haled In excessive amounts, so-called "nuisance" dust& have a long history of tittle adverse effect on lungs and do not produce significant organic disease or toxic effect
when exposures are kept under reasonable control. The nuisance ousts have aJso 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 iuno when inhaled in sufficient amount. However, toe lung-tissue reaction caused by in halation of nuisance dusts has the following characteris tics: (1) The architecture of the air spaces remains in tact. (2) Collagen (scar tissue) Is not formed to a
5
t
,
*
AP00043614
significant extent. (3) The tissue reaction is potentially
reversible. Excessive concentrations of nuisance busts In the
workroom air may seriously reduce visibility, may cause unpleasant deposits in the eyes, ears and nasal pas* sages (Portland Cement dust), or cause injury to the skin or mucous membranes by chemical or mechanical action per se or by the rigorous skin cleansing proce
dures necessary tor their removal. A threshold limit of 10 mg/ma, or 30 mppcf, of total
dust < 1% quartz, or, 5 mg/m3 respirable dust is rec ommended tor substances in these categories and for which no specific threshold limits have been assigned. This limit, for a normal workday, does not apply to brief exposures al higher concentrations. Neither does it
apply to those substances which may cause physiologic Impairment at lower concentrations but for which a threshold limit has not yet been adopted. Some nuisance particulates are given In Appendix E.
Simple Asphyxiants -- "Inert" Gases or Vapors. A number of gases and vapors, when present in high con centrations in air, act primarily as simple asphyxiants
without other significant physiologic effects. A TLV may not be recommended for each simple asphyxiant be cause the limiting factor is the available oxygen. The minimal oxygen content should be 18 percent by volume under normal atmospheric pressure (equivalent to a par tial pressure, pQs of 135 mm Hg). Atmospheres deficient in Os do not provide adequate warning and most simple asphyxiants are odorless. Several simple asphyxiants present an explosion hazard. Account should be taken of this factor in limiting the concentration of the asphyx iant. Specific examples are listed In Appendix F,
Physical factors. It is recognized that such physical factors as heat, ultraviolet and ionizing radiation, humidity, abnormal pressure (altitude) and me like may place added stress on the body so that the effects from expo
sure at a threshold limit may be altered. Most of these stresses act adversely to Increase the toxic response of a substance. Although moat threshold limits have built-in safety factors to guard against adverse effects to moder ate deviations from normal environments, the safety fac tors of most substances are not of such a magnitude as to take care of gross deviations. For example, continu ous work at temperatures above SWF, or overtime ex tending the workweek more than 2594, might be consld-
6
ered gross deviations. In such instances judgment must be exercised in the proper adjustments of the Threshold Limit Values.
Biologic Limit Values (BLVs). Other means exist and may be necessary for monitoring worker exposure other than reliance on the Threshold Limit Values for Industrial air, namely, the Biologic Limit Values. These values rep resent 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 measure ments on which the BLVs ere based can furnish two kinds of information useful in the control ol worker ex posure: (1) measure of toe individual worker's-over-all exposure; (2) measure of the worker's individual and characteristic response. Measurements of response fur nish a superior estimate of the physiologic status of the worker, and may be made of (a) changes In amount of some critical biochemical constituent, (b) changes in ac tivity of a critical enzyme, (c) changes in some physiolo gic 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 metaboltte(s) of the substance in tissues and fluids; (3) determination of the amount ol the substance In the exhaled breath. The biologic limits may be used as an adjunct to the TLVs tor air, or in place of them. The BLVs, and (heir associated procedures for determining compliance with them, should thus be regarded as an effective means of providing health surveillance of the worker.
Unlisted Substances. Many substances present or handled In industrial processes do not appear on the TLV list. In a number of instances the material is rarely present as a particulate, vapor or other airborne con taminant, and a TLV is not necessary, in other cases sufficient information to warrant development of a TLV,
even on a tentative basis, is not available to the Commit tee. Other substances, of low toxicity, could be included in Appendix E pertaining to nuisance particulates. This list (as well as Appendix F) Is not meant to be all inclu sive: the substances serve only as examples.
In addition there are some substances of not incon siderable toxicity, which have beer omitted primarily be cause only a limited number of workers (e.g., employ-
7
AP00043615
ees of a single plant) are known to have potential exposure to possibly harmful concentrations.
"Notice of Intent." At the beginning of each year, proposed actions of the Committee for the forthcoming year are issued in the form of a "Notice of Intended Changes." This Notice provides not only an opportunity 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 Values 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.
Legal Status. By publication in the Federal Register (Vol. 36, No. 105. May 29, 1971) the Threshold Limit Values for 196B were made official federal standards for Industrial air. Since 1971, new standards for certain of these substances have been promulgated by OSHA.
Reprint Permission. This publication may be reprint ed provided that written permission is obtained from the Secretary-Treasurer of the Conference and that it be published in its entirety.
8
ADOPTED VALUES
TWA tubatanceppm*' mg/m**1
Abate...........................
10
Acetaldehyde................ 100
ISO
|
Acetic acid....................
10
25
>
C Acetic anhydride...........
s
Acetone....................... 1.00D
20 2,400
Acetonitrile....................
40
70
Acetylene...................... F --
Acetylene dchloride, see
1,2-Dichloroeiitylene. 200
790
Acetylene letrabromlde...
1
14
Acrolein....................... Aciylamide -- Skin.......
0.1 __
0.25 0.3
`Acrylonitrile -- Skin...... Aldrin -- Skin...............
(20)
(45) 0.25
Allyl alcohol -- Skin.....
2
5
Aiyi chloride................ Allyl glycfdyl ethBr
1
3
(AQE) -- Skin...........
5
22
Allyl propyl disulfide......
2
12
!
Alundum (AltOa) ..........
__
E
4-Amnodiphenyl -- Skin -- Alb 2-Aminoethanol, see
Ethanolamine............
3
a
2*Aminopyridlne...........
0.5
2
Ammonia...................... Ammonium
25
18
chloride-fume...........
--
10
Ammonium sulfamate (Animate).................
_
10
n-Amyl acetate.............
100
530
see-Amyl acetals........... 125
670
Aniline --Skin.............. Anlsldine (o-,
(5)
(19)
p-isomere) -- Skin.... Antimony & Compounds
0.1
0.5
(as Sb).....................
(0-5)
* Antimony trioxide,
handling and use (as
Sb)...........................
--
o.s
** Antimony trfoxlde
production (as Sb).....
-- (0.5, A2)
Capital letters refer to Appendices. Footnotes (i thru g) see Page 31. "See Notices of Intended Changes. *1978 Addition
TENTATIVE VALUES
STEL ppm*' tng/m**'
150
_15
1,250
60 --
20 270
_37
3,000 105 --
250 1,000 1.5 18
0.3 0.8 0.6
(30) (65) 0.75
4 10
2a
10 44
3 18 __ 20 -- Alb
6 15 24 35 27
-- 20
-- 20 150 600 150 600 --
----
---- ----
9
n r l[ i j
ji
;
.1
.
1 >1
\
AP00043616
f]
Substance
ADOPTED VALUES
TWA ppm" mfl/m**1
TENTATIVE VALUES
m ppnr" !Bg/m,w
ANTU (a*Naphthyl
Argon........................... ' Arsenic & compounds
(as As)..................... ** Arsenic irloxlde
production (as As).....
Arsine.......................... Asbestos (all forms)...... Asphalt (petroleum)
fumes....................... Alrulne.......................
Azinphos-methyl-- Skin Barium (soluble
compounds), as Ba.... Baygon (propoxur)........
Benzene....................... Benzidine
production --Skin....
p-BenzoQUinone. see
Qulnone................... Benzoyl peroxide........... Benz(a)pyrene.............. Benzyl chloride.............
BetyHium...................... Biphenyl...................... C Blsphenol A, see
Digtycidal ether (DGE). Bismuth telluride........... Bismuth telluride,
Se-doped..................
Boreles, tetra, sodium salts, Anhydrous................ Oecahydrate............. Pantahydrate............
Boron oxide..................
Boron tribromide........... C Boron trifluoride...........
Bromine....................... Bromine pentafluorfda...
F
--
-- 0.05
--
-- -- --
-- --
10,A2
--
0.1 -- --
1 -- 0.2
0.5
--
--
-- --
-- 1 1
0.1 0.1
0.3 --
(0.5)
(Ala) 02 (Ala)
5 10 0.2
0.5 0.5 30, A2
Alb
0.4 5
A2 5
0.002 1.5
3.0 10
5
1 5 1 10 10 3 0.7 0.7
_ 0.9
FF
----
---- ---- -- (Ala)
-- 10 ---- -- 0.6
---- --2 ----
-- Alb
0.3 2 ---- -- A2 ---- -- 0.025 0.6 4
---- -- 20
-- 10
-- --. -- --
3 -- 0.3 0.3
-- -- --20
30 --
2 2
Capital letter! rtter to Appendices. Footnotes (t thru g) sea Page 31.
''See Notice of Intended Changes `1976 Addition.
10
Substance
Bromochioromethane/ chlorobromomethane.
Bromoform -- Skin......
Butadiene (1. 3-butadlene).............
Butane.......................... Butanethiol, see Butyl
mercaptan................ 2-Butanone.................. 2-Buloxyethanol (Butyl
Cellosolva)--- Skin.... n-Butyl acetate.............. sec*6utyl acetate........... tert-Butyl acetate........... ' Butyl acrylate................ Cn-Butyl alcohol --Skin.. tec-Butyl alcohol...........
twt-Butyl alcohol........... C Butytsmlne -- Skin....... Ctart-Buiyi chromate (as
CrOs) -- Skin...........
n*Bufyi glyddyl ether (BGE).......................
n-Butyl lactate..............
Butyl mercaptan............ p-tert-Butyltoluene......... Cadmium, dust & salts
(as Cd)..................... C Cadmium oxide fume (as
Cd)...........................
* Cadmium oxide production (asCd).....
Calcium carbonate/
marble...................... Calcium arsenate (as As) Ctlcium cyanamld*...... . * Calcium hydroxide.........
* Calcium oxide............... Camphor, synthetic........ Caprolactam Oust......................... Vapor.......................
ADOPTED VALUES
TWA ppm* mg/m1*"
200 0.5
1,000 600
0.5 200
50 150 200 200
10 50 150 100 5
--
50 5 0.5 10
--
_
--
__
-- _ 2
___
5
1,050 5
2,200 1,430
1.5 590
240 710 950 950 55 150 450 300
15
0.1
270 25 1.5 60
0.05
0.05
(A2)
E 1 0.5 5 2 12
T
20
TENTATIVE VALUES
m ppm*'
- 250 1,300 ----
1,250 750
2.750 1.760
--
300 B65
ISO 720
200 950
250 1,190 250 1.190
--
-- ----
150 --
45_0_
----
---- ---- ---- 20 120
-- 0.2
__
----
--_
20 __
t ----
_ __
3 18
_3
10 40
Capital letters refer to Appendices. "See Notice of Intended Ranges. *1976 Addilnn.
11
1 | ; i i ,
0'
\i
AP00043617
Midi
Sabstanee
Captafol (Dttolatin*) -- Skin...
Captan..........................
Carbaryl (Sevin*)......... Carbofuran (Fundan*)..
Carbon black................ Carbon dioxide............. ** Carton
disulfide -- SMn....... Carbon monoxide.......... Carbon tetrabromkle..... Carton
tetrachloride --Skin..
* Carbonyl chloride (Phosgene)...............
Carbonyl fluoride........... Catechol (Pyrocatechol).. Cellulose (paper fiber).... Cesium hydroxide.......... Chlordane -- Skin........ Chlorinated tamphene -- Skin..... Chlorinated diphenyl oxide........................ Chlorine....................... Chlorine dioxide............
C Chlorine trifluoride......... C Chloroacetaldehyde.......
a-CItlonoawtophenone (Phenacyl chloride)....
Chlorobenzene (Monochlorobenzene).
o-Chlorobenzylidere matonoitrlle -- Skin...
Chiorobromomethane/ Bromochloromethane
2-Chloro-1,3-butadiene, see /S Chloroprette --
Skin.......................... Chiorodifluoromethana. Clttorodlphenyl(42%
Ctiiorine) -- Skin......
ADOPTED VALUES
TWA ppm" mp/m*"
TENTATIVE VALUES
STEL ppm4' mp/m**1
--
--
--
--
5,000
(20) SO 0,1
10
0.1 5 5
--
--
--
C1 0.1 0.1 1
0.05
75
0.05
200
0.1 5
5 0.1 3.5 9,000
-- --
--
--
15,000
(60) (30) 55 400 1.4 0.3
65 20
0.4 15 -- 20 -- E-- 2-- 0.5 --
0.5 _
0.6
33
0.3 0.4
0_.3
3--
0.3
350 ,, 0.4 _
1.050 250
15 10 --7 19,000
(90) 440
4
130
-- -- 20 --
2
1
2 9
0_.9
--
_
1,300
25 1,000
'_
90 3,500
1
35 1,250
_
125 4,375
2
Capital latter* refer to Appendices. "See Notice ol Intended Changes. 197a Addition.
12
ADOPTED VALUES
TWA Substanceppm" mpm1*1
Chlorodiphenyl (54% Chlorine) -- Skirt......
0.5
1-Chloro, 2, 3-epoxy-propane (Eplehlorhydrin) -- Skin..........................
; 2-Chloroethsnol (Ethylene
chlorohydrin) -- Skin,
1 Chloroetirylene (Vhyl chloride)..................
' Chloroform
(Trichloromethane).... bis-Chforometliyf ether...
1-Chloro-l-nitro-propane Chioropterin.................
1 fJ-Chloroprene -- Skin.. Chlorpyrilos
(Dursban*) -- Skin... o-Chlorostyrene............ o-Chlorotoluene -- Skin.
2-Chlaroftrlchioromethyl
pyridine (N-Serve*}... Chromates, certain
Insoluble forms.........
Chromic add and Chromates, (as Cr)....
Chromite ore processing (chromate), as Cr......
Chromium. Sol. chromic, chromous salts (as Cr)..............
Oopidd (Coyden*)......
Coal tar pitch volatiles (See Particulate polycyclic aromatic hydrocarbons)...........
Cobalt metal, dust and fume (as Co)............
5 20
1
(Ale)
10, A2 0.001
20 0.1 (25)
50 50
3
50, A2 Ata 100 0.7 (90)
0.2 285 250
10 0.05, Ala
0.05 0.05, Ala
_
0.5 10
0.2, Ala
_ (0.1)
TENTATIVE VALUES STEL
ppm" mg/m**'
1
10 40
(Ale)
_ _
0.3 (35)
75 75
A_la
2 (135)
0.6 430 375
20 Ala
20
Ala
_
Capital tetters rater to Appendices. Footnotes (i thru g) see Page 31. '`See Notice or intended Changes. *1973 Addition.
13
; :i
fej Li
S
I
i
V
AP00043618
duiittfiifi
Stbslancs
Copper luma.................
Ousts & Misti (as Cu)
Corundum (Ab &).......
Cotton dust, raw...........
Crag* heitJeide............
Cresot, all
isomers -- Skin.......
CTDtonatdetyde............
Crufomate*..................
Cumene -- Skin...........
Cyenamide...................
Cyanide, as CN --Skin..
Cyanogen ..................... Cyclohexane.................
CyclOftexanol................
Cyclohexanone.............
Cyclohexene................. Cyclohexylamina -- Skin
Cydopentadiene.,.......... 2. 4-D (2, 4-Diphenoiry-
acetic acid)......................... DDT (Dlchlorodiphenyl-
tnchloroethane)...............
DDVP, see Dlehlorvos --
Skin ;..................... ....................
Deceborane -- Skin........... Demeton* -- Skin.............
Diacetone alcohol (4-hydroxy-4-methyl-
2-pentanone)..................... 1,2-Dlamlnoethana, see
Ethylenediamine............... Dlazlnon -- Skin....................
Dtaometharw..........................
Dibore ne...................................... * 1,2-Dlbromoethane
(Ethylene dlbromkle)
Stin--
....................................
Dlbrom*...................................... 2*N-Oibutylamkioothanol
--Skin....................................
Dlbutyl phosphate...............
I) Seep. 33.
Footnotes (a thru g) see Page 31. "See Notice ot Intended Changes.
ADOPTED VALUES
twa
ppm" mi/m**'
___ 0,2 --1 --E -- 0.2ft -- 10
5 22 26 --5 50 245 --2 --5 10 20 300 1,050 50 200 50 200 300 1,015 10 40 75 200
-- 10
TENTATIVE VALUES
STEl
ppm" mp/m**
____
.--
2
e
_ 0.6 -- 20
____
6 IS -- 20 75 365
----
----
___ --
375 1.300 . -- --!
--
--
-- 150 400 * I
s1
20 ,
1 3. !
0.1
1 (1.3
3,
0.05 0.3 0.15 0.9 1
0.01
0.1 0.03
0.3'
50 240 75 360 '
10 25 _
--
0.2
0.1 -- 0.4
0_.3
0.1 0.1 "
(2--0)
(155} 3
(30)
_
(230) 6l
2 14 4 28
1
52
10
14
Substancepprr1
ADOPTED VALUES
TWA
TENTATIVE VALUES
STEL ppm4' mg/m1*'
Dibutyi phthalate...........
--
C Dfehioracetylsne...........
0.1
C o-Dichioroberuene.........
50
p-Dtehlorobanzene........
75
Dichlorabenzidine--
Skin..........................
Dichlorodilluoromethane. 1.000
1,3-Olchloro-5,
5-dimethyl hydpitoln..
1,1-Olchloroethane...... 200
** 1.2-DicWoroethane...... (50)
1.2-Dichloroethylene.... 200
Dichtoroethyl ether--
Skin..........................
5
'* Dichtorcmettme. see Methylene chloride.... (200)
** Dichloromonofluoro-
methane.................... (1,000)
Cl.i-Dichioro-V nftroethane................
10
1, 2-Dfchloroprooane,
see Propylene
dichiDride.................
75
Dichlorotelrafiuoro-
ethane...................... 1.000
Dichlorvos (DDVP)
-- Skin..................... 0.1
Dicrotophos (Btdrln*) -- Skin..........................
_
Dicyclopantadiene.........
5
Dicyclopentadlenyl iron..
--
Dieldrin -- Skin.............
--
Diethytamine................. Oiethyiaminoethenot --
Skin..........................
25 10
Otethylene triamine --
Skin.......................... Diethyl ether, see Ethyl
1
ether........................ 400
. Diethyl phthalate........... Oifluarodibromomettiane.
--
100
5 0.4 300 450
A2 4.950
0.2 810 (200) 790
30
(700)
(4,200)
60
350
7.000
1
0.25 30 10
0.25 75
50
4
1.200 5
860
-- --
-- 110
1,250
250 (75) 250
10 (250)
.
110 1,250
0.3 --
-- -- -- _
500
--
150
10
--
-- 675
A2 6,200
0.4 1,010 1300) 1.000
60
(670)
_
510 8.750
3 __
--
20 0.75
--
1.500 10
1.290
Capital letters refer to Appendices. * * See Notice ot Mended Changes.
15
\
AP00043619
Sublimes
ADOPTED VALUES
TWA ppm*1 rap/m9*'
COiQtycijyl ttier(OGE)....
0.5
DiHydrokybenzene, see
Hydroquinone............
--
Dllsobutyl ketone.......... Oiisopropylimins --
25
Skin...........................
5
Dimethoiymethane, su
Methylal..................... 1,000
Dimethyl acetamide --
Skin...........................
10
* Dimethyl carbamyl
chloride.....................
A2
Dimethylamine..............
10
Dimethylamirtobenxene,
see Xylidene -- Skin.. Dtmethylaniline(N,
5
N-DImethylanillne) --
Skin...........................
5
Dimetftylbenaene, see
Xylene -- Skin........... 100
Dlmethyl-1,
2-<jSbromo'2*<frctiloroathy1
phosphate, see Dibrom......................
--
Dlmethyiformamide --
Skin...........................
10
2, 6-OknethyM`heptanone,
see Diisobutyl ketone.,
25
i, l*Dimethyltydmzine
--Skin...................... Dimethylphthelate..........
0.5 --
C Dimethyl sulfate -- Skin. 0..1,A2 Dinltrobeniene (all
Isomers) -- Skin........ Din/tro-o-cresOl --Skin , 3,5-Dinttro-O'toluamld*
0.15 --
|2oalene*j.................
Dinitrotoluene-- Skin... Oloxane, tech, grade --
-- --
Skin...........................
50
Dioxathion (Oelnav*) --
Skin...........................
3 2 150 20 3.100 35 A2 19 25
25 435
a 30 150
1 5 0.5. A2 1 0.2 5 1.5 160 0.2
Capftal Istlsri refer to Appendices.
Footnote* (i thru g) see Page 31. '1976 Addition.
16
* TENTATIVE
VALUES STEL
ppm** eBp/m**''
__
--4 --
1.250 15 -- -- 10
10 150
-- 20 --
1 -- -- 0.5 -- --
--
--
3,875
50
__
_
50 *
50 ' *
650 %
,
6 i
60 *
--'
2i 10 --
3 0.6
10 5
--
.
ttkitiMi
Diphenyl, see Biphenyl... Diphenylamine............. C Oiphenyimethane
dlisocyanate. see Methylene bisphenyi isocyanate (MDI)....... Dipropylene glycol methyl ether --Skin.. Oiquat..........................
Di*sec. octyl phthalate (Di-2-ethylhexylphthalate).................
Disulfiram..................... Dlsyston --Skin........... 2, 6-DHert.
butyi-p-creeol........... Dluron..........................
Dyfonate...................... Emery.......................... Endoeuifan (Thiodtn*)
-- Skin..................... Endrln -- Skin............. ** Epichlortiydrin-- Skin... EPN -- Skin................. 1, 2-Epoxypropane, see
Propylene oxide.........
2,3*Epoxy*1 -propanol, aee GJyeidor...............
Ethane..........................
Elhanethiol.see Ethyl mercaptan................
Ethanolamine................ Ethion(Nialati*) -- Skin
2-Etftoxyethanol -- Skin. 2-EMwxyethyl acetate
(Ceitcsotve acetate) --
Skin.......................... Ethyl acetate................. Ethyl acrylate -- Skin ....
Ethyl alcohol (Ethanol)... EthyUmine...................
ADOPTED VALUES
TWA ppm" ms/nr
0.2 1.5 -- 10
0.02 0.2 100 600 -- 0.5
--5 --2 -- 0,1
-- 10 -- 10 -- 0.1 --E
--_
0.1 0.1
(5) (2D)
-- D.5
100 240
50 150 F--
0.5 1 38
-- 0.4
100 370
100 400 25
1,000 10
540
1.400 100
1,900 18
TB4TAT1VE VALUES
STEL ppm" mpim9
0.6 4 -- 20
150 900 --1
-- 10 --5 -- 0.3
-- 20 ---- -- -- 20
-- 0.3 -- 0.3 (10) (40) --2
150 360
75 225 --
23 6 15 ---- 150 560
1--50
810 --
----
----
----
Capital letters refer to Appendices. "See Notice of Intended Changes.
17
I
il iii it. !l; |; I it
if f
;l
}i i j.i j; Ml 1
l r.; r1 i*i jtj LI ;i
i J
\
AP00043620
mk
ADOPTED VALUES
TWA ShHwppm01 mg/m**1
Ethyl sec-amyl ketone (4-Metliyl-3-
heptanone)................ Ethyl benzene................
Ethyl bromide............... Ethylbutyl ketone
(3-Heptanone)...........
Ethyl chloride................ Ethyl ether................... Ethyl formate............... Ethyl mercaptan............
** Ethyl sillicate................
Ethylene....................... C Ethylene chlorohydrln --
Skin.......................... Ethylenediamine............ ' Ethylene dfbromlde, see
1,2-0ibromoethane... * Ethylene dlchlorlde, see
1,2-Dtehiuroethane... Ethylene glycol,
rarticulate................ Vapor.......................
C Ethylene glycol dinitrate and/or Nitroglycerin -- Skin....................
Ethylene glycol monomethyl ether acetate (Methyl cellosoive acetate] -- Skin.........................
Ethylene oxide..............
Ethylenlmine -- Skin..... Ethylldene chloride, see
1.1-Dichioroethane ... C Ethylldene rtorbomene...
N-Ethylmorpholine -- Skin..........................
FensuKothion [Dasanit].. Ferbam........................
Ferrovinedium dust...... Fluoride (as F)...............
Fluorine.......................
25 100 200
50 1,000
400 100 0.5 (100)
F
1 10
(20)
(50)
100
130 435 890
230 2,600 1,200
300 1
(850) __
3 25
(155)
(200)
10 250
0.2* 2
25 120 50 90 0.5 1
200 - 810 5 25
20 94
0.1
__ 10
__ __
1
2.5
12
TENTATIVE VALUES
STEl ppm*' mg/nn**1
__ 125 250
75 1,250
500 150
2 __
F
__ __
(30)
(75)
125
545 1.110
345 3.250 1.500
450 3
__
__
(230)
(300)
20 325
__ _
35 170
_75 135
_
_250 I.DIO
__
_
__ _ __ 20 --* 0.3 _ 24
apltal letters refer lo Appendixes. 'See Notice of Intended Changes.
18
AOOPTED VALUES
TWA Substanceppm"*
TENTATIVE VALUES
STEL ppm1* mg/m**1
Fluorotrichloromethane .. C Formaldehyde...............
Formamlde....................
Formic acid.................. Furfural--Skin............ Furfuryl alcohol -- Skin . Gasoline.......................
Germanium tetrahydride. Glass, fibrous'1 or dust.. C Gfutaraioehyde, activated
or unacthated...........
Glycerin mist................
Glycldol (2, 3-Epoxy1-propanol)...............
Glycol monoethyl ether, eee 2-Ethoxyethanoi -- Skin.....................
Graphite (Synthetic)...... Guthion*. see
Azlnphos-methyl --
Skin.......................... Gypsum ....................... Hafnium....................... Heium.......................... Heptachlor -- Skin........ Heptane (n-Heptane)..... Hexachlorocyclopenta*
diene........................ Hexachloroethane --
Skin.......................... Hexachioronaphthalene
-- Skin..................... Hexafluoroacetone......... Hexane (n-hexane)......... * Hexamethyl
phosphoramlde --
Skin.......................... 2-Hexanone, see Methyl
butyl ketone --Skin.. Hexone (Methyl isobutyl
ketone) -- Skin.........
1,000 2
20 5 5
_5
0.2 --
-- --
50
100
-- -- --
F
--
400
0.01
1
--
0.1 100
A2
25
100
5,600
3 30
9 20 20 B2
0.6 10
1,250 --
30
--
15 10
.--
0.6
(0.25) E
-- --
150 75
370 150 E
0.2 E
0.5 -- 0.5 1,600
0.1
10
0.2 0.7 360
-- -- --
F
--
500
0.03
3
--
0.3 125
A2 -- 100 40 410 125
7,000 -- 45 -- 60 40 62 1.8
-- E
225
560
0.6 20 1.5 --
2 2.000
0.3
30
0.6 2
450
165
510
Capital letters refer to Appendices.
Footnotes (a thru g) see Page 31. 1978 Addition. 'See Notice of Intented Changes.
19
J
i >)
J 1 ll ! 1
,i j1 11 !l1 !
AP00043621
Substance
ADOPTED VALUES
TWA ppm" mj/m**'
aec-Hexyl acetate..........
50
C Hexylene glycol............
25
Hvdraaine -- Skin......... 0.1. A2
Hydrogen.....................
F
Hydrogenated terphenyls
0.5
Hydrogen bromide........ C Hydrogen chloride.........
3 5
Hydrogen cyanide -- Skin..........................
Hydrogen fluoride..........
Hydrogen peroxide........ Hydrogen setenide......... Hydrogen sulfide........... Hydroquinone..............
Iridene.......................... Indium & Compounds
(as In)......................
(10) 3 1
0.05 10 -- 10
--
C Iodine........................... Iodoform......................
0.1 0.6
iron oxide fume............ Iron pentacaibonyl........ Iron salts, soluble (as
Fa).......................... Isoamyl acetate............
B3 0.01
__ 100
Isoamyl alcohol............ 100
Isobutyl acetate............ isobutyl alcohol............
' C laophorone..................
150 50
5
tsophorone diisocyanate -- Skin ,.
Isopropyl acetate...........
isopropyl alcohol -- Skin Isopropylamine.............
0.01 250 400
5
isopropyl ether............. 250
Isopropyl glyddyl ether (ICE)........................
Kaolin...........................
Ketene..........................
50 0.5
Lead, inorg.. fumes & dusts (as Pb)............
Lead arsenate (as Pb).,,,
-- --
Lead chromate (as Cf),..
300 125 0.1, A2
-- 5 10 7
(ID 2
1.5 0.2 15
2 45
0.1 1
10 5 0.08
1
526
360 700 ISO 25
0.0$ 950 980 12 1,050
240 E
0.9
0.15 0.15 0.05, A2
TENTATIVE VALUES
STEL ppm" mp/m**''
__ ---- -- ---
F-- ---- ----
OS) (16) ---- 23 ---- 15 27 ` --4 15 70 -
-- 0.3 ? ----
1 20 ; -- 10 *
--2 125 655 * 125 450* 187 875 . 75 225 *
~l
-- 310 1.185 i 500 1,225
10 24 310 1,320
75 --
360
20
1.5 3
-- 0.45 -- 0.45
"
Capital Man refer to Appendices. "See Notice of Intended Changes.
20
ADOPTED VALUES
TENTATIVE VALUES
TWA Substanceppm" mg/m**' ppm01 mg/m^1
STEL
Limestone..................... Lindane--Skin............ Lithium hydride............ L.P.G. (liquified
petroleum gas).......... Magnesite..................... Magnesium oxide fume
(as Mg)..................... Malathion -- Skin......... Maleic anhydride...........
Manganese & Compounds (as Mn)..
Manganese
cyclopentadienyl tricarbonyl (as Mn) -- Skin..........................
' Manganese Tetroocide..... Marble/calcium carbonate.................
Mercury (Alkyl compounds) --Skin,
(as Hg)..................... Mercury (All forms
ncept alkyl), as Hg ...
Mesityl oxide................ Methane....................... Methanethioi, see Methyl
mercaptan................ Melhomyl (Lannatc*) --
Skin.......................... Methoxychlor................
2-Methoxyethanol -- Skin (Methyl cellosoive)................
Methyl acetate............... Methyl acetylene
(propyne).................
Methyl acetylene-propadlene mixture (MAPP)............
Methyl acrylate --Skin..
__ -- --
1.000
--
_
--
0.25
__
--
--.
0.001
_
25 F
D.5
_
--
25 200 1.000
1,000 10
E 0.5
0.025
-- -- --
1,800 E
10 10
1
5
1,250 --
_
--
--
__
20 1.5
--
2,250 20
_
--
--
_
0.1
1--
E_
0.3
--
20
0.01 0,003
0.05 100
--
1
2.5 10
--
F
__
_
--
0.03
0.15
-- -- __
--
80 610
1.650
35 250
250
120 760
2.040
1,600 35
,250 --
2.250 --
Capital letters refer to Appendices *1978 Addition.
21
\
AP00043622
untriiiiaaM
I
Substance
ADOPTED VALUES
TWA ppm*' mg/m*6'
Metftylacrylon Itrfle --
Skin..........................
1
Methylal
(dimethoxymethane).. 1,000
Methyl alcohol (methanol) --Skin....
200
Methytamine.................
10
Methyl amyl alcohol, see
Methyl isobutyl
carbinol -- Skin....... Methyl 2-cyanoaerylate..
25 2
Methyl n-amyl ketone
(2-Heptanone)........... 100
Methyl bromide -- Skin .
15
Methyl butyl ketone, see
2-Hexanone -- Skin...
25
Methyl cellosolve-- Skin see 2-Methoxyethanol.
25
Methyl cellosolve acetate
-- Skin, see Ethylene
glycol monomethyl
ether acetate.............
25
Methyl chloride.............
100
Methyl chloroform (1,1.
l-Trlchloroethane)..... 350
Methylcyclohexane....... Methylcydohexanol.......
400 50
o-Methycyclohexanone
-- Skin.....................
50
Melhylcyclopentadienyt
manganese tricarbonyl
(as Mn) -- Skin......... 0.1
Methyl demeton -- Skin.
--
Methylene blsphenyl isocyanate (MDI)........
Methylene chloride
0.02
(dichlDromethane)..... (200)
4,4'*Methyfene bis
(2-chloraniline) --
Skin.......................... 0.02. A2
Methylene bis (4-cydo-*
hexyllsocyanate)....... 0.01
3 3,100
260 12
100 8
465 60 100
flO
120 210 1,900 1,600 235 23D
0.2 0.5 0.2 (700)
--
0.11
TENTATIVE VALUES STEL
ppm*' mg/m*"
2
1,250
250
--
6 3,875
310 --
40 160 4 16
1_50 71_0
40 1S5
35 120
35 170 125 260
450 2,380 500 2,000 75 350
75 345
0.3
--
--
(250)
0.6 1.5 --
(870)
A2 __ ----
Substance
Methyl ethyl ketone (MEK), see 2-Butanone...............
C Methyl ethyl ketone peroxide....................
Methyl formate............. Methyl iodide --Skin.... Methyl isoamyl ketone...
Methyl Isobutyl carbinol -- Skin.....................
Methyl isobutyl ketone, see Hexone --Skin...
Methyl isocyanate -- Skin..........................
Methyl mercaptan..........
Methyl methacrylate...... Methyl perathion -- Skin Methyl propyl ketone.
see 2*Pentanone....... C Methyl silicate............... C a-Methyl styrene...........
Molybdenum (as Mo)
Soluble compounds... Insoluble compounds. Monocrotophos (Azodrin*)................ Monomethyl aniline --
Skkt.......................... C Monomethyl hydrazine
--Skin.....................
Morpholine -- Skin........ Naphthalene.................
/8-Naprtthylamine.......... Neon............................ Nickel carbonyl.............. Nickel metal.................
Nickel, soluble compounds (as Ni)....
Nickel sulfide roasting, fume & dust (as NI)...
Nicotine -- Skin...........
Nitric acid.....................
ADOPTED VALUES
TWA ppm*'
200 590
0.2 1.5 100 250
5 28 100 475
25 100
1O0 410
0.02 0.05 0.5 1 100 410
-- 0.2
200 700
5 30 100 480
5 --. 10
-- 0.25
29
0.2 0.35
20 70
10 50
-- Alb
F--
0._0_5
0.35 1
-- 0.1
-- 1 .Ala -- 0.5
25
TENTATIVE VALUES
STEL ppm*1 mg/m**'
300 885
---- 150 375 10 58 150 710
40 165
125 510
---- ---- 125 510 -- 0.6
250 675 ---- ----
-- 10 -- 20
----
4 18
----
30 105
15 75
--
F
A_ID
_
_
0.3 ---- -- 1.5
4 10
CapHal letters refer to Appendices. "See Notice ol Intended Changes
22
Capital litters refer to Appendices Footnotes (a trim g> see Page 31.
23
t
AP00043623
it
Substance
ADOPTED VALUES
TWA ppnr5 mg/m**1
TENTATIVE VALUES
STEL ppm'' mp/m**1
Nitric oxide.................. p-Nftroanlllne--Skin.... Nitrobenzene --Skin.....
p-NItrochlorobenzene -- Skin.........................
4-Nltrodiphenyl.............
NUroethane..................
C Nitrogen dioxide........... Ntrogen trifluoride........
C Nitroglycerin Skin.....
Nitromethane................ 1Nttropropane............. " 2*Nltropropane.............. N-Nitroscdimethylamlne
(dimethylnitrosoamlne) -- Skin..................... Nltrotoluene -- Skin...... Nllrotrichloromethane, see Chloroplcrln.........
Nonane........................ Octachlorcuiaphthalene
-- Skin.....................
Octane.......................... Oil mist, mineral........... Osmium tetroxide (as
Os)...........................
Oxalic acid................... Oxygen difluoride.......... Ozone...........................
Paraffin wax fume......... * Paraquat, respirable
slaes........................
Parathlon -- Skin.......... Particulate polycyclic
aromatic hydrocarbons (PPAH),
as benzene solubles... Pentaborane................. Pentachloronaphthalene .
Pentachlorophenol -- Skin..........................
25 1 1
-- -- 100
5 10 0.2* 100 25 (25)
--
5
0.1 200
-- 300 --
0.0002 --
0.05 0.1 --
-- --
-- 0.005
--
--
. 30 $ 5
1 Alb 310
9 29
2 250
90 (90)
A2 30
0.7 1,050
0,1 1,450
5
0.002 t
0.1 0.2
2
0.1 0.1
0.2. Ala 0.01 0.5
0.5
36 2 2
-- -- 150 -- 15 -- 150 35 --
-- 10
0.3 250
-- 375 --
0.0006 --
0.1$ 0.3 --
-- --
-- 0.015
--
--
4S 12 10
2 Alb 465
-- 45 -- 375 135 --
A2 60
2 1,300
0.3 1.t00
10
0.006 2
0.3 0.6
6,
-- 0.3
All 0.03
2
1.5
Capital letters refer to Appendices. Footnotes (i thru g) see Page 31.
*1978 Addition.
"See Notice of Intended Changes.
24
Substance
Pentaerythritoi...............
Pentane....................... 2-Pentanene................. pBrchloroethylene --
Skirt.......................... Perchiorometliy!
mercaptan................
Perchloryl fluoride......... Phenol --Skin............. Phenothiazine -- Skin.... p-Phenylene diamine --
Skin.......................... Phenyl ether (vapor)...... Phenyl ether-Diphsnyl
mixture (vapor)......... Phenylethyiene, see
Styrene, monomer..... Phenyl glycidyl ether
(PGE)....................... Phenyl mercaptan..........
Phenyihydrazine -- Skin. CPhenyiphosphlne...........
Ptwrate (Thimet*)-- Skin..........................
Phosdrin (Mevlnphos*) -- Skin.....................
' Phosgene (carbonyl chloride)..................
Phosphine.................... Phosphoric acid........... Phosphorus (yeliow)..... " Phosphorus
pentacbtorWe............ Phosphorus perrtasulfide Phosphorus trichloride... Phthallc anhydride.........
m-Phthalodlnltrlle.......... Plcioram (Tordort*)...... Picric acid--Skin...... Pfvaf* (2-Pto/yl-f. 3*
indandione)............... Plaster of Paris..............
Capital letters refer to Appendices.
1878 Addition.
"See Notices of Intended Changes.
ADOPTED VALUES
TWA ppm*' raj/m^
__ E 600 1.800 200 700
100 670
0.1 0.8 3 14 5 19
--5
-- 0.1
7
17
100 420
ID 60 0.5 2
5 22 0.05 0.25
__ 0.05
0.01 0.1
0.1 0.4 0.3 0.4 --1 -- 0.1
-- (D _1 0.5 3
16 --5 __ 10
0.1
-- 0.1 --
25
TENTATIVE VALUES STEL
fpm*> mg/m*1
__ 20 750 2.250 250 875
150 1,000
---- 6 28
10 38 -- 10
---- 2 14
2 14
125 525
15 90 ---- 10 44 ----
0.2
0.03 0.3
__ -- 11
--3 -- 0.3
-- (3) --3
-- 4 24 ---- __ 20 __ 0.3
--
_
0.3 20
1 I1 1 ||: '!| ! i;i
|, l !l! ;!
.1
1! h1:1 1;
h !1
ri i.! 1' t>:
;]
A
AP00043624
.Substance
Platinum (Soluble salts) as Pt........................
Polychlorobiptwiyls, see Ctttorodfphenyis -- Skin..........................
Polytetrafluoroethylene decomposition products..................
C Potassium hydroxide.....
Propane....................... S-Proptolactone............ Propargyl alcohol --
Skin.......................... n-Propyl acetate............ Propyl alcohol --Skin... n-Propyl nitrate............ Propylene..................... Propylene dlchlorkle (1,
2-Oichloropropane).... `C Propylene glycol dinkrate
-- Skin..................... Propylene glycol
monomethyl ether........ Propylene In-line -- Skin.
Propylene oxide............
Propyne, see Methyl acetylene.......... ........
fyrethrum................................... Pyridine......................................... Guirtone......................................... RDX -- Skin..............................
Resorcinol................................... Rhodium, Metal fume
and dusts (as fih)........... Soluble salts (as Rh).. Ronnel.......................... Rosin core solder pyrolysis products (as formaldehyde)........... Rotertone (commercial).. Rouge..........................
ADOPTED VALUES
TWA ppm*' mg/m**
-- 0.002
----
-- --
F
1 200 200 25
F
75
0.2
too 2
100
1,000
--
5 0.1
--
10
-- -- --
B1 2 -- A2
2 040 500 105 _
350
2
360 5
240
1,650 5 15
0.4 1.5 45
0.1 0.001
10
-- 0.1
--5 --
TENTATIVE VALUES
STEl ppm" mq/m**
* --
ti
___
T
-- 01 --
F ___ ___ A2
36 250 1.050 250 625 40 470 F
110 510-
-- ___
150 540
--
150 360
,250 2.040 -- 10 10 30 0.3 2' --3 20 90
-- 0.3 -- 0.003
----- --
--_
0.3 10
-- 20
Subiteiwi
Rubber sotverrt (Naphtha).................
Selenium compounds (as St)...........................
Selenium hexafluoride. as Se.......................
Sevin* (see Carbary!).... Silane (see Silicon
tetrahydride)............. Silicon.......................... Silicon carbide.............
Silicon telrahydride (Silane).....................
Silver, metal and soluble
compounds, as Ag.... C Sodium azide................
Sodium fluorotcetate (1080) --Skin..........
C Sodium hydroxide......... Starch.......................... Stlbine.......................... Stoddard solvent........... Strychnine.................................. Styrene, monomer
(Phenylethylene)........ C Subtlllsins (Proteolytic
entymes as 100%
pure ciystalline enzyme).................................. Sucrose........................................ * Sulfur dioxide.......................... Sulfur hexafluoride............. Sulfuric acid..............................
Sulfur monochloride...... Sulfur pentafluoridB...... Sulfur tstrafluoride........ SuHuryl iiuoride............ Systox.eeeDemeton*
-- Skin..................... 2.4, 5-T...................... Tantalum......................
ADOPTED VALUES
TWA ppm'" mg/m>*'
400 1,600
-- 0.2
0.05 0.4 --5
0.5 7 --E ___ e
0.5 0.7
-- (0.01) 0.1 0.3
__ 0.05 --2 --E 0.1 0.5 100 575 -- 0.15
100 420
-- 0.00000"
___ E
(5) 1,000
(13) 6,000
___ 1
16
0.025 0.1 5
0.25 0.4 20
0.0_1
0.1 10
--5
TENTATIVE VALUES
STEL
ppm" mg/m**1
-- __
__
0.D5 --
1 --
___
1
__ __
0.4 10
2 20 20
2
(0.03)
___
___ 0.15 __ __
-- 20
0.3 1.5
1_25
720 0.45
125 525
-- ___ --
1.250
3 0.075
0.3 10
0.03
--
___
20
7.500 _ 18
0.75 1
40
0.3 20 10
j
! t j i ; .
:
, *
Cxpfol letters refer to Appendices. 1978 Addition.
26
Caoltn letters refer to Appendices. "See Notice ot intended Changes.
27
\\
AP00043625
V
SabeUftee
TEDP--Skin................ Teflon* decomposition
products.................. Tellurium 4 compounds
(e*Te)...................... Tellurium hexafluoride.
asTe........................ TEPP -- Skin................ *C Terphenyls.................... 1,1.1, 2-Tetrach)oro-2,
2-difiuoreethine....... 1,1,2, 2-Tetiachioro-i,
2-difiucroethane........
1,1,2. 2-Tetmchloroethsne
--Skin..................... Tetrachloroethylene, see
Perehloroelhyiene -- Skin......................... Tatrachioromethane, see Carbon tetrachloride
-- Skin..................... Tetnchforonaplttnaiene.. Tetraethyl lead (as Pb)
-- Skin........ ............ Tetrahydnofuran....... .
Tetramethyi lead (as Pb) -- Skin.....................
Tetramethyi succinonltrile-- Skin.
Tetranrtromathane.........
Tet/y) (2, 4, 6-trinttrophenylmelhylrotnmlrte) -- Skin..........................
Thallium, soluble compounds (as Ti>-- Skin..........................
4, 4*-Thlobis (6-tert. butyi-nvcresol)..........
* ThioglycoBc acid...........
ADOPTED VALUES
TWA ppm*> mg/iir
_ 0.2
-- B1
-- 0.1
0.02 0.004
(1)
500
0.2 0.05
(9)
4,170
500 4.170
$ 35
100 670
10 65 --2
-- 0.100** 200 500
-- 0.150**
0.5 3 18
1.5
0.1 -- 10
I5
TENTATIVE VALUES ITEL
ppm*' mg/m**' -- 0.6 -- 61 ----
--_
0.01 0.2 ----
625 5,210 626 5,2113
10 76
150 1,000
20 130 --4 -- 0.3 250 735
-- 0.5
4 29 _ --
" 3.0
-- 20 "
Capital letters ntei to Appendices.
*1978 Addition.
"See Notice ot Intended Changes.
28
SubstiMi
Thiram*.......................
Tin. Inorganic compounds, except SnhU and Snk (as Sn)
Tin, organic compounds (as Sn) -- Skin.........
Tin oxide (asSn)........... Titanium dioxide (asTi).. Toluene (toluol) -- Skin .
**CToluene-2, 4-diisocyanate (TDI)...
o-TolukJine................... Toxapherte, see
Chlortnsted camphene -- Skin...... .............. Tributyl phosphate......... *01,2.4-Trtehlorobeiu*ne 1,1,1-Trichtoroethane, see Methyl chloroform 1,1,2-TrieMorerthine -- Skin..................... Trichloroethylene.......... Triehlororoethane, see Chloroform............... Trichloronaphthatene..... 1.2.3>Trichloropropane 1,1, 2-Trichloro 1,2, 2-trtfluoroethane........ Triethylamlne................
Trlcyclohexyltin hydroxide (Pilctran*).
Trifh/oromorwhrwno' methane....................
Trlmethyl benzene......... 2, 4, 6-Tiinitrophenal,
2, 4, 6-Trlnltrophenylmethyinitramlne, see Tetryi Skin...........
ADOPTED VALUES
TWA ppm*' mg/mr
--5
--
-- -- -- 100
(0.02) 5
2
0.1 E E
375
(0.14) 22
-- --
5
350
10 100
10, A2 -- 50
1,000 25
--
1,000 25
0.5 5
40
1,900
45 535
50. A2 5
300
7,600 100
5
6.100 125
O.l
1.5
TENTATIVE VALUES STEL
ppm" mg/m*
-- 10
--4
-- 0.2 -- 20 -- 20 150 560
---- 10 44
--
-- --
440
20 150
-- -- 75
1.250 40
--
1,200 35
_
2.0 5
--
2,380
90 BOO
-- 10 450
9,500 160
10
7,300 170
0.3
3.0
(TNT)....................... -- 0.5 --
--
Capital lelters retv to Appeidices.
`1978 Addition.
"See Notice of Intended Changes.
29
\
AP00043626
Substanceppm8' mg/m1*1
ADOPTED VALUES
TWA ppm*1 mj/m**1
TENTATIVE VALUES
STEL
Triorthocresyf phosphate Trlphenyl phosphate...... TunQsten & compounds,
18 W Soluble................. Insoluble...............
Turpentine................... Uranium (natural)
soluble & Insoluble compounds, as U...... Vanadium (V*0e),asV
Dust........................
C Fume........................ * Valeraldehyde...............
Vinyl acetate.................
Vinyl benzene, see Styrene.....................
** Vinyl bromide..............
*' Vinyl chloride................
Vinyl cyanide, see Acrylonitrile--Skin...
Vinyl cyclohexene dioxide.....................
Vinylidene chloride........ Vinyl toluene.................
Warfarin.......................
Welding fumes (NOC)*.. Wood dust
(nonallergenic).......... Xylene (o-, in-,
p-isomars) -- Skin.,,.
C m-Xyleneo, a'-diamhe. Xylidene--Skin........... Yttrium........................ Zinc chloride fume......... Zinc chromate (as Cr)....
Zinc oxide fume............ Zinc stearate................. Zirconium compounds
(as Zr)......................
0.1 3
_1
__ 5 100 560
-- 0.2
--
_
0.5 0.05
50 175
10 30
100 (250) (AlC)
420 (1,100)
20 45
10 60 10 40 100 480 -- 0.1
-- 5, 63
--5
1_00
435 0.1
5 25 --1 --1
-- 0,05, A2
--5
--E
--5
_
__ 150
--
_ _
__ 20
150 --(AlC)
30
-- 20 150 -- --
--
IS_O _10
-- -- --
--
--
0.3 5
3 10 B4D
0.6
1.5
_ 60
630 --
65
__ 80 720 0.3 83
b IP
655
--
SO 3
_2
10 20
10
Capital letters retar to Appendices. +(NDC) not otherwise classified 1978 Addition. 'See Notice of Intended Changes.
30
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) An atmospheric concentration of not more than 0.02 ppm, or personal protection may be necessary to avoid headache for intermittent exposure.
e) < 7/xm in diameter. 1) As sampled by method that does not collect vapor, g) For control of general room air, biologic monitoring
is essential for personnel control.
Radioactivity; For permissible concentrations of radio isotopes In air, see U.S. Department of Commerce, Na tional Bureau of Standards Handbook 69, "Maximum Permissible Body Burdens and Maximum Permissible Concentrations of Radionuclides in Air and In Water for Occupational Exposure," June 5, 1959; Addendum 1, August 1963 (NCRP Report No. 22). Also, see U.S. De partment of Commerce National Bureau of Standards. Handbook 59. "Permissible Dose from External Sources of lonliino Radiation," September 24, 1954, an adden dum of April 15, 1958. A report, Basic Radiation Protec tion Criteria, published by the National Committee on Radiation Protection, revises and modernizes the con cept of the NCRP standards of 1954, 1957 and 1958; obtainable as NCRP Rept. No. 39, 7910 Woodmont Ave., Washington, O.C. 20014.
Substance SiUCA, SiOz
Crystalline Quartt
MINERAL DUSTS
TLV in mppcf10:
300
% quartz +10 TLV for respirable dust In mg/mJ:
10 mg/m*0 % Respirable quartz + 2 TLV for "total dust," respirable and nonrespirable;
30 mo/m3 % quartz + 3
31
APOOO'
Crlstobalite............ Use one-half the value calculated
from the count or mass formulae
for quartz.
Tridymlte
Use one-half the value calculated
from formulae for quartz.
Silica, fused
Use quartz formulae.
Tripoli
Use respirable" mass quartz for
mula
"Amorphous.............................................. (20 mppcfkl)
SILICATES (< 1% quartz)
"Asbestos, all forms
Mica Mineral wool fiber Perlite Portland Cement Soapstone Talc (nonasbestiform) ''Talc (fibrous), use Asbestos limit. 'Tremolfte, see Asbestos.
(5 fibers/cc> 5^m In length"1; Ala) 20 mppcf 10 mg/m3
30 mppcf
30 mppcf 20 mppcf 20 mppcf
COAL DUST 2 mg/m3 (respirable dust fraction < 5% quartz), if > 5% quartz, use respirable mass formula.
NUISANCE PARTICULATES (see Appendix E)
30 mppcf or 10 mg/m**1 of total dust < i*> quartz, or, 5 mg/m3 respirable dust.
Conversion factors: mppct x 35.3 - Million particles per cubic meter - particles per cc
h) Millions of particles per cubic foot of air, based on impinger samples counted by light-field technics.
i) 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 appll-
"Set Notice of Intended Changes. 32
w
cation of this limit are to be determined from the fraction passing a size-selector with the following
characteristics:
Aerodynamic Diameter (pm)
(unit density sphere) =e2 2.5 3.5 5.0 10
% passing
selector 80 75 50 25 0
k) containino <1% quartz; if quartz content > 1%, use formulae for quartz.
l) Lint-free dust as measured by the vertiabeiutriator, cotton-dust sampler described In the Transactions of tire National Conference on Cotton Dust, J. R. Lynch,
pg. 33, May 2,1970. m) As determined by the membrane filter method at
4OO-450X magnification (4 mm objective) phase con trast illumination. n) Based on "high volume" sampling. o) "Respirable" dust as defined by the British Medical
Research Council Criteria (1) and as sampled by a device producing equivalent results (2). (1) Hatch, T. E. and Gross, P., Pulmonary Deposi
tion and Retention of inhaled Aerosols, p. 149. Academic Press, New York, New York, 1964. (2) Interim Guide for Respirable Mass Sampling. AIHA Aerosol Technology Committee, ahia j. 31: 2, 1970, p. 133.
NOTICE OF INTENDEO CHANGES (for 1978)
These substances, with their corresponding values. Comprise those for which either a limit has been pro posed for the first time, or for which a change In the "Adopted'1 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 lioht that ques tions the appropriateness of the values herein, the val ues will be reconsidered for the ''Adopted" list. Docu mentation is available for each of these substances.
33
\ i
AP00043628
m
Substance________
* Acetylsalicylic acid (Aspirin)....................
+ Acrylonitrile.................. Aluminum metal and
oxide......................... Aluminum pyro powders. Aluminum welding fumes Aluminum, soluble sails.
Aluminum, alkyls (N0C}` 3-Amino 1. 2, 4-tria20le . t Aniline and homoiogues
-- Skin..................... Antimony, soluble sails
[as Sb)..................... Antimony Irioxlde
production................ Arsenic (soluble), as As.
Arsenic trioxide production................
t Baytex.......................... Benomyl....................... Bromacil......................
+ o-sec Butylphenol-- Skin..........................
Cadmium oxide production.;..............
t Carbon disulfide............ + Ctiloraacetyi chloride..... t CWoromethyl methyl
ether........................ t /S-Chloreprene---Skin...
Cobalt metal, dust & fume (as Co)............
+C Cyanogen chloride......... Cyclopentane................
* Delapon....................... t, 2-Dibromoettian* --
Skin..........................
+ Olchloromonofluoromethane....................
i- Dichloropropene........... + Diethanolamine............. i- Divinyl benzene............ + Epichlorhydrine --Skin..
TWA pprr" milm*
--5 A1C A1C
-- 10 --5 --5 --2 --2 A2 A2
2 10
--2
-- --, A2 0.2
-- --, Ala -- 0.1 -- 10 -- 10
5--
-- --,A2 10 30 0.05 0.2
Alb Alb 10 45
-- 0.05 0.3 0.6 300 850
1"
Ale Ale
10 40 15 3 15 10 50 2 10
STEL ppm*' mg/m**
----
-- 20 ---- ---- ---- ----
5 20
----
---- -- 0.3 -- 15 -- 20 ---- ---- ----
----
----
-- 0.1
----
450 1,000 ----
--
----
10 50
---- ----
5 20
Capital letters refer to Appendices 1878 Revision or Addition. *Not otherwise classified (NOC).
34
TWA STEL Substanceppm01 mg/m^ ppmal mg/it/'
Ethyl silicate.................
t Ethylene dibromide, see 1, 2-Dibromoethane...
+ Ethylene dichtoride, see 1,2-Dichloroethane...
C Glutaraldahyde............. Hexachtorobutadiene.....
tc Hydrogen cyanide -- Skit..........................
t 2-Hydroxypropyl acrylate
-- Skin..................... t N'lsopropylaniline --
Skin..........................
Manganese fume (as Mn)..........................
t Methylene chloride
(dichloromethane)..... t4,4-Methylene cfiartiline. tC2-Nitropropane..............
Phenyl-beta*
naphthylamine........... t Phosphorous
psntachloride............ t Propionic acid............... t Slver, metal.................
+ Sodium bisulflle............
t Sodium metabbuffite.....
t Sulfur dioxide............... tCTerphenyls....................
t Tetrasodlum pyrophosphate..........
t Totuene*2,
4*<fil9ocyanate (TDl)... t Trichloroacetic acid....... + Vinyl bromide............... t vinyl chloride................
VM A P Naphtha...........
10
AlC
10 0.2 A2
10
0.5
2
--
100 0.1 25. A2
A2
0.1 10 -- --
_
2 0.5
--
0.002.
--
5. A2
5, Ala
300
65
Ale
40 0.6 A2
10
3
10
1
360 0.8 80, A2
A2
1 30 0.1 5 5 5 5
5
0.015 1
20, A2
TO, Ala
1,350
30
--
15 -- --
--
--
5
500 0.5 --
--
-- 15 -- --
-- 5
--
0.005
-- -- -- 400
250
--
60
----
--
--
20 3
1,700
4
--
45 --
-- 15 --
0.035
-- -- -- I.BOO
,
;
5
I 1 :
tapktl letters refer to Appendices. 1S7S Addition.
35
\
AP00043629
NOTICE OF INTENDED CHANGES MINERAL DUSTS
Substance T Asbestos
Amosite............... Chrysotlle............ Orocidollte........... Tremolite............ Other forms........ Dlatomaceous earth, nature................ Slilca, amorphous...
t Talc (fibrous).
TLV
0.5fiber/cc, Ala 2 ftbers/cc, Ala 0.2 fiber/cc, Ala 0.5 fiber/cc, Ala 2 flbers/cc, Ala 1.5 mg/m*. Respirable
dust 5 mg/ms, Total dust
(all sampled sires) 2 mg/m3, Respirable
dust (< 5 titn) 0.5 flber/cc
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 exper imental conditions. Present listing of those substances carcinogenic for man takes three forms: Those for which a TLV has been assigned (la), those for which environ ments! conditions have not been sufficiently defined to assign a TLV (lb), and (1c), those whose reassignment of a TLV is awaiting more definitive data, and hence should be treated as s lb carcinogen.
Ala. Homan Carcinogens. Substances, or substances associated with industrial processes, recognized to have carcinogenic or cocardnogenlc potential, with an assigned TLV:
TLV
*' Arsenictrioxide production
(AseOs, 0.05 mg/m3 as As)
(SQz, C 5.0 ppm)
**$ Notice of intended Chenges +1978 Addition.
36
. .
m*
"Asbestos, all forms*
bis (Chloromethyl) ether Chromite ore
processing (chromate) Nickel sulfide roasting, . fume & dust Particulate Polycyclic Aromatic Hydrocarbons (PPAH)
Vinyl Chloride
(SbzOa, 0.5 mg/m* (as 8b))
(5 fibers/cc, > 5*tm In length)
0.001 ppm
0.05 mg/ms (as Cr)
1.0 mg/m3 (as Nl)
0.2 mg/ms, as benzene solubles
5 ppm
Alb. Homan Carcinogens. Substances, or substances associated with industrial processes, recognized to have carcinogenic potential without an assigned TLV;
Chloromethyl methyl ether 4-Aminodlphenyl (p-Xenylamine) Benzidine production beta-Naphthylamlne 4-Nltrodlphenyl
Ale. Human Carcinogens. Substances with recognized carcinogenic potential awaiting reassignment o` TLV pending further data acquisition:
Acrylonitrile 1,2-Dibromoethane (Ethylene dlbromkle)
For the substances In 1b or 1c, no exposure or contact by any route -- respiratory, skin or oral, as detected by the most sensitive methods -- shalt be permitted, "No exposure or contact" means hermltizlng the process or operation by the best practicable engi neering methods. The worker should be properly equipped to insure virtually no contact with the carcinogen.
`Cigarette emoking can enhance the incidence of respiratory eaneere from this and others of these substances or processes.
37
i
AP00043630
A2, Industrial Substances Suspect of Carcinogenic Po
tential for MAN. Chemical substances or sub'
stances associated with industrial processes, which are suspect of Inducing cancer, based on
either (1) limited epidemiologic evidence, exclusive
of clinical reports of single cases, or (2) demonstration of carcinogenesis In one or more animal
species by appropriate methods.
3-Amino 1,2, 4-trfazole * * Antimony trioxlde production"
Benzene Benz(a)pyrene Beryllium "* Cadmium oxide production Chloroform Chromates of lead and zinc (as
Cr) 3. 3'-Dlctilorobenzidine Dimethytearbamyl chloride 1.1 -Dimethyl hydrazine Dimethyl sulfate -- Skin Epichlorhydrin HexacMorobutadlene
Hexamethyi phosphoramide -- Skin
Hydrazine Lead chromate 4, 4'-Metrtyiene bis
(2-chloroaniiine) -- Skin Monomethyl hydrazine
C2-Nltropropane Nitrosamines Phenyl-beta-naphthylamine Propane sultone beta-Propiofaotone Vinyl cyclohexane dioxide
Zinc chromate (as Cr)
(0.5 mg/m5) 10 ppm
2.0/ig/m3 (0.05 mg/rn5) 10 ppm
0.05 mg/m3
0.5 ppm 0.1 ppm 5 ppm
0.1 ppm 0.05 mg/m3
0.02 ppm 0.2 ppm 25 ppm
10 ppm 0.05 mg/m3
For the above, worker exposure by all routes should be carefully controlled to levels consistent with the animal and human experience data (see documentation), including those substances with
a listed TLV.
"Cigarette smoking can enhance the inelOtnee of respiratory cancers from this or others of these substances or processes.
38
A3. Guidelines for the Classification of Experimental
ANIMAL Carcinogens. The following guidelines are offered in the present state of knowledge as an aid in classifying substances in (he occupational envi ronment found to be carcinogenic in experimental animals. A need was felt by the Threshold Limits Committee lor such a classification In order to take the first step in developing an appropriate TLV for occupational exposure.
Determination of Approximate Threshold of Re sponse Requirement, in order to determine in which category to classify an experimental carcin ogen tor the purpose of assigning an industrial air limit (TLV), an approximate threshold of neoplastic response must be determined. Because of practi cal experimental difficulties, a precisely defined threshold cannot be attained. For the purposes ot standard-setting, this is of little moment, as an ap propriate risk, or safety, factor can be applied to the approximate threshold, the magnitude of which is dependent on the degree of potency of the car cinogenic response.
To obtain the best practical' threshold of neoplas tic response, dosage decrements should be less than logarithmic. This becomes particularly impor tant at levels greater than 10 ppm (or correspond ing mg/m5). Accordingly, after a range-finding de termination has been made by logarithmic decreases, two additional dosage levels are re quired within the levels of "effect" and "no effect" to approximate the true threshold ot neoplastic re sponse.
The second step should attempt to establish a me tabolic relationship between animal and man for the particular substance found carcinogenic in an imals. If the metabolic pathways are found compa rable, the substance should be classed highly sus pect as a carcinogen for man. if no such relation is found, the substance should remain listed as an experimental animal carcinogen until evidence lo the contrary Is found.
Proposed Classification of Experimental Animal Carcinogens. Substances occurring in the occupa tional environment found carcinogenic for animals
39
AP00043631
f;
may be grouped into three classes, those of high. Intermediate and low potency, in evaluating the in cidence of animal cancers, significant Incidence of cancer is defined as a neoplastic response which represents, In the judgment of the Committee, a significant excess of cancers above that occurring
In negative controls.
EXCEPTIONS: No substance is to be considered an occupational carcinogen of any practical signifi cance which reacts by the respiratory route at or above 1000 mg/mJ for the mouse, 2000 mg/m5 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 Iitetime, equivalent to about 100 p T.D, for
the rat, lOg T.O. forth mouse,
These dosage limitations exclude such substances 26 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/kgrd), oral
i I
1
j
1
, INDUSTRIAL SUBSTANCES OF HIGH CARCINO GENIC POTENCY IN EXPERIMENTAL ANIMALS
1. A substance to qualify as a carcinogen of high potency must fulfill one of the three following . conditions In two animal species:
la. Respiratory. Elicit cancer from (1) dosages below 1 mg/m* (or equivalent ppm) via the respiratory tract in 6- 7-hour daily repeated Inhalation exposures throughout lifetime; or (2) from a single Jntratracbeally admin istered dose not exceeding 1 mg of parti culate, or liquid, per 100 ml or less of an imal minute respiratory volume;
Examples: bis-Chioromethyl ether, malign ant tumors, rats, @ 0.47 mg/rn3 (0.1 ppm) in 2 years;
40
Hexamethyl phosphoramlde, 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;
Examples; 7, 12-Dlmethylbent(a)anthracene -- skin tumors @ 0.120.8 mg T.D. in four weeks
Benz(a)pyrene, mice 12 ng. dX/wk for 18 mos. T.D. 2.6 mg, 90.9% skin tumors
OR
lc. Gastrointestinal. Sfcit cancer by dally 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 tog; mouse, * 3.5 mg;
Examples: 7, 12-Dlmettiylbenz(a)anthra cene -- mammary tumors from 10 mg IX
3-Methyicholanthrene -- Tumors @ 3 sites from 8 mg in 69 weeks
Benz(a)pyrene, mice, 3.9% leukemias, from 30 mg T.D. 196 days
2. Elicit cancer by ail three routes in at least two animal species at Ooae levels prescribed for high or intermediate potency.
A3b. INDUSTRIAL SUBSTANCES OF INTERMEDIATE CARCINOGENIC POTENCY IN EXPERIMENTAL AN IMALS
To qualify as 1 carcinogen of intermediate potency, a substance should elicit cancer In two animal spe-
41
V
}
AP00043632
cies at dosages intermediate between those de scribed in A3a and A3c by two routes of adminis tration.
Example: Carbamlc 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.
A3c INDUSTRIAL SUBSTANCES OF LOW CARCINO GENIC POTENCY IN EXPERIMENTAL ANIMALS
To qualify as a carcinogen of low potency, a sub stance should elicit cancer in one animal species by anyone of three routes of administration 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, dally re peated Inhalation exposures, tor 12 months' exposure and 12 months' observation period; or (2) from intratracheally administered dos ages totaling more than 10 mg of particulate or liquid per 100 ml or more of artlmal minute respiratory volume;
Examples: Betyl (beryllium aluminum silicate) malig. lung tumors, rats, @ 15 mg/ms@ 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, l.e., ^ 1.5g T.D.
Examples: Shale tar, mouse, 0.1 ml x 50 g T.D, 59/60 slan tumors
Arsenic trioxide, man, dose un known, but estimated to be high
lc. Gastrointestinal. Elicit cancer from daily oral
42
dosages of 50 mg/kg/day or greater durlno the lifetime of the animat.
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 con taining carbon, fluorine and oxygen. Because these products decompose in part by hydrolysis in alkaline solution, they can be quantitatively determined in air as fluoride to provide an index of exposure. No TLV is recommended pending determination of the toxi city of the products, but air concentrations should be minimal.
B2 Gasoline. The composition of gasoline varies greatly and thus a single TLV for all types of these materials is no longer applicable. In general, the aromatic hy drocarbon content will determine what TLV applies. Consequently the content of benzene, other aromat ics and additives should be determined to arrive at the appropriate TLV (Elkins, et al. A.I.H.A.J. 24:99, 1963); Runion.ibid.J6, 338.1975).
B3 Welding Fumes --TotalParticulate (NOC)**
TLV, 5 mg/m3
Welding fumes cannot be classified simply. The com position and quantity of both are dependent on the alloy being welded and the process and electrodes used. Reli able analysis of fumes cannot be made without consider ing the nature of the welding process and system being examined: reactive metals and alloys such as aluminum and titanium are arc-welded in a protective, inert atmo sphere such as argon. These arcs create relatively little fume, but an Intense radiation which can produce ozone. Similar processes are usBd to arc-weld steals, also creating a relatively low level of fumes. Ferrous alloys also are arc-welded in oxidbing environments which generate considerable fume, and can produce carbon monoxide instead of D2one. Such fumes generally are composed of discreet particles of amorphous slags con-
*Tiade Names: Algoflon. Fluon, Halon, Teflon. Tetran. * ' Nat otherwise classified (NOG).
43
i*
tabling iron, manganese, silicon and other metallic con stituents depending on the alloy system involved. Chro mium and nickel compounds are found in fumes when stainless steels are arc-welded. Some coated and fluxcored electrodes are formulated with fluorides and the fumes associated with them can contain significantly more fluorldBS than oxides. Because of the above fac tors, arc-welding fumes frequently must be tested for individual constituents which are likely to be present to determine whether specific TLV*s are exceeded. Conclu sions 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 controlled.
APPENDIX C MIXTURES
C.1 THRESHOLD LIMIT VALUES FOR MIXTURES
When two or more hazardous substances are present, their combined effect, rather than that of either indi vidually, should be given primary consideration, (n the absence of information to the contrary, the effects of the different hazards should be considered as additive. That is. if the sum ofthe following fractions,
,
exceeds unity, then the threshold limit of the mixture should be considered as being exceeded. Ci Indicates the observed atmospheric concentration, and T> the cor responding threshold limit (See Example 1A.. 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 additive, -tiAimhpMdent as when purely local effects on different organs of the body are produced by the various compo nents of the mixture. In such cases the threshold limit ordinarily is exceeded only when at (east one member of
44
the series
+ or +
etc.j itself has a value
exceeding unity (See Example 1A.c.). Antagonistic action or potentiation may occur with
some combinations of atmospheric contaminants. Such cases at present must be determined individually. Poten tiating or antagonistic agents are not necessarily 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 exhi bited at high concentrations, less probably at low.
When a given operation or process characteristically 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 sub stance. In such cases, the threshold limit used for this substance should be reduced by a suitable factor, the magnitude of which will depend on the number, toxicity and relative quantity of the other contaminants ordinarily present.
Examples of processes which are typically associated with two or more harmful atmospheric contaminants are welding, automobile repair, blasting, painting, lacquer ing, certain foundry operations, diesel exhausts, etc.
C.1A Examples of THRESHOLD LIMIT VALUES
FOR MIXTURES
The following formulae apply only when the compo nents in a mixture have similar toxicologic effects; they should not be used for mixtures with widely differing reactivities, e.g. hydrogen cyanide & sulfur dioxide. In such case the formula for Independent Effects (lA.c.) should be used.
lA.a. General case, where air Is analyzed for aach com ponent;
a. Additive effects. (Note: It Is essential that the atmosphere be analyzed both qualitatively and quantitatively for each component present. In order to evaluate compliance or noncom pliance with this calculated TLV.)
45
k
AP00043634
idMtk
Example No. 1A.a.: Air contains 400 ppm of acetone (TLV = 1000 ppm) 150 ppm of secbutyl 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.
lA.b. Special case when the source of contaminant is a liquid mixture and the atmospheric composition is assumed to be similar to that of the original mate rial; e.g. on a lime-weighted average exposure basis, all of the liquid (solvent) mixture 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.
(Afore; In order to evaluate compliance with this TLV, Held sampling instruments should be calibrated, in the laboratory, for response to this specific quantitative and qualitative airvapor mixture, and a/so to fractional concen trations of this mixture; e.g., 1/2 the TLV; W0 the TLV; 2 x the TLV; 10 x the TLV; etc)
TLV of mixture
TLV. + TLV{, + TLVf + ` ' ' TLV.
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/mJ 1 mg/ms 0.28 ppm
46
20% perchloroethylene: TLV - 100 ppm or 670 mg/m3 1 mg/m3 0.15 ppm
TLV of Mixture - -p- jjj pj
1600 + 1900 + 670
0.00031 + 0.00016+ 0,00030 ra07T`,300mg,m>
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/ms 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/m9 of lead (TLV, 0.15) and 0.7 mg/ni* of sulfuric acid (TLV, 1).
JU*-f 0.15
-2=1=07 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% nonasbestiform talc and 20% quartz, the TLV for 100% of the mixture is given by:
in
; '! I .j ;
20 + 2.7 TLV of nonasbestiform talc (pure) = 20 mppcf
47
\
AP00043635
TLV of quartz (pure) 300 _ 300
100+10 110
2.7 mppcf
Essentially the same result will be obtained If the limit of the more (most) toxic component 1$ 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) * mppcf
50% talc TLV (pure) - 20 mppcf
TLV _________ 1 0,25 , 0.25 , 0,5
2.7 20
20
8 mppcf
f
The limit for 25% quartz approximates 9 mppcf.
APPENDIX D PERMISSIBLE EXCURSIONS FOR TIME-
WEIGHTED AVERAGE (TWA) LIMITS
The .Excursion TLV Factor in the Table automatically defines the magnitude of the permissible excursion
above the limit for those substances not given a "C" designation; i.e., the TWA limits. Examples in the Table
show that nitrobenzene, the TLV for which is 1 ppm, should never be allowed to exceed 3 ppm. Similarly,
carbon tetrachloride, TLV * 10 ppm, should never be allowed to exceed 20 ppm. By contrast, those substances with a "C" designation are not subject to the excursion factor and must be kept at or below the TLV celling.
These limiting excursions are to be considered to provide a "rule-of-thumb" guidance for listed substances generally, and may not provide the most appro-
priate excursion for a particular substance e.g., the per missible excursion far CO is 400 ppm for 15 minutes.
For appropriate excursions for 142 substances con-
suit Pa. Rules & Regs.. Chap. 4, Art 432, and "Accept able Concentrations," ANSI.
i > ! 'j
j
| \
; I
48
iH
Substance
Nitrobenzene Carbon tetrachloride Trlmethy! benzene Acetone Boron trifluoride Butylamine
Excursion TLV Factor
1 10 25
1000 C1 C5
3 2 1.5 1.25
--
--
Max. Cone. Permitted for short
time
2 20 35 1250
1 5
EXCURSION FACTORS
For all substances not bearing C notation
TLV>0-1 (ppm or mg/ms),
TLV>V10
"
TLV> 10-100
"
TLV> 100-1000 "
Excursion Factor
" "
-3 -2 - 1.5 -1.25
The number of times the excursion above the TLV Is permitted is governed by conformity with the TimeWeighted Average TLV.
INTERPRETATION OF MEASURED PEAK CONCENTRATIONS
With Increasing use of rapid, direct-reading-analytical instruments for airborne contaminants in the work-area, the question of Interrelation of essentially "Instanta
neous" peaks arises. Although no general statement can be made covering all occupational substances, the fol lowing guidelines should prove helpful, assuming peak excursions conform W time-weighted average TLV as stated above.
The toxicologic importance of momentary peak con centrations depends on whether the substance Is fast or slow acting. If slow acting, as for quartz, lead, or car
bon monoxide, momentary peaks are of no toxicologic
concern provided, of course, they are not astronomic. On the other hand, -fast-acting substances that rapidly
produce disabling narcosis, e.g., HS, or intolerable irri tation orasphyxiation, NH, SQt, CO*, or initiate sensitiza tion -- the organic isocyanates, even "instantaneous"
peaks appreciably above the permissible excursion,
should not be permitted, unless Informatlonwxtets to the
49
!
AP00043636
contrary. Other more specific excursions will be devel oped in the future.
APPENDIX E Some Nuisance Particulate*"' TLV, 30 mppcf or 10mg/m3 of total dust < 1% quartz, or. 5 mg/m3
respirable dust
1. In 1967. Jacobsen andTomb.t derived an empir cal relationship of 5.6 mppcf to 1 milligram respirable dust per cubic meter of air, based c 23 sets of samples, mostly coal dust. The follow ing calculation results in an equivalence of 6.1 mppcf to 1 mg/m3 of respirable dust. Thus, i approximate ratio of 6 mppcf to 1 mg/m* of r spirable dust is suggested for conversion of Tl\
Aiundum (AbOa) Calcium carbonate Calcium silicate
limestone Magnesite Marble
from a count to s mass basis when the densi and mass median diameter have not been detc mined.
Cellulose (paper fiber)
Mineral Wool Fiber
Portland Cement Corundum (AbOs)
Pentaerythritol Plaster of Paris
2. Basic assumptions:
Emery Glycerin Mist Graphite (synthetic)
Gypsum Vegetable oil mists
Rouge Silicon
Silicon Carbide Starch Sucrose
a) Average density for silica containing dusts * 2.5 gms/cm3 (2500 mg/cm3). Pulmonary sic nificant dust densities may vary from 1. gm/em9 for coal dust to 3.1 gms/cm* f< Portland Cement. Silica densities vary fro
(except castor, cashew nut, or similar irritant oils)
Kaolin
Tin Oxide Titanium Dioxide
Zinc Stearate Zinc oxide dust
2.2 (amorphous) to 2.3 (errstobatite and trid; mite) to 2.5 (alpha-quartz.) gms per cm3.
b) Tne mass median diameter (mmd) of particle collected in midget impinger samplers ar
p) When toxic impurities are not present, e.g. quartz <
counted by the standard light field teohnlqu.
1%. anti collected in a respirable sampler is ai
APPENDIX P Some Simple Asphyxiant*'
Acetylene Argon Butane
Ethane Ethylene
Hydrogen Methane Neon Propane Propylene
proximately 1.5 ^m or 1.5 x 10"4 cm. Th assumption is, of course, quite arbitrary $in< the mmd of all dust clouds is quite variabl depending on many independent parameter: such as source of dust, age of dust cloud, mteorologica) conditions, etc.
Helium
3. Calculation:
q) As defined on pQ. 6. APPENDIX 6
a) vol. per particle: 4/3 ir r3: r = 0.75 x iqcm
- 4/3 ir (0.75 x 10-4)3
Calculations for Conversion of Particle Count Concen
- 1.77 x IO-12 cm9
tration (by Standard Light Field -- Midget Implnger
b) wt. per particle - vol. x density
III
Techniques), in mppcf, to Respirable Mass Concentra tion (by Respirable Sampler) in mg/m3.*
= 1,77 x 10"1* cm* x 2.5 x 103 mg/cm3 - 4,425 x 10-* mg/particle
^"Relationship Between Gravimeiric Respirable Oust Concentration and Midget Implnger Number Conewrtratton." tjy Murrey Jicobson and T. F.
Tomb, AiHAJ, 28; Nov.-Dee. 1967.
c) 1 particle/ft.* * 35.5 part./m* (since 35.5 ciift - 1 cu m.)
10* part./fl3 = mppcf = 35,5 x 10* part./m
50 51
AP00043637
wt. of 1 mppcf 35.5 x 10* part./m3 x ^
4,425 x 10- mg/part.
1 mppcf 0.157 mg/m* or
6.37 mppcf * 1 mg/m9 or approximately 6 mpccl 1
mg/m*.
4. Equivalent TLVs in mppcf and mg/m3 (respirable mass) for Mineral Dusts.
1
Substance
Threshold Limit Value
Count Resp. Mass Total Mass'
mppcf mo/m3
mo/m*
Silica (SiQj Amorphous Cristobal ite Fused silica Quartz
Tridymfte Coal Dust Dtatomaceous earth,
natural Graphite (natural)
'Mica Mineral wool fiber Nuisance particulates
Perlite Portland Cement Soapstone
Talc (nonasbesliform)
Tripoli
20 1.5 3 3 1.5
(12)
--
15 20
--
30 30 30 20
20 (3)
or 0.05 0.1 0.1 0.05 2
1.5 (2.5) (3) (5) (5) (5) (5) (3)
O) 0.1
(6) 0.15 0.3 0.3 0.15 (4)
-- (5) (6) 10 10
S8 (6)
(6) (0.3)
I
TLVs Threshold Limit Values
for Physical Agents
Adopted by ACGIH for 1978
`Unless otherwise specified, respirable mass is presumed to equal ap proximately 50% of total mess.
**A| values In parentheses () represant newly caieuMad values based on equivalence at 6 mppcf 1 mg/tti* respirable mass and raspir* able mass * 50% total mass.
52
AP00043638
1978 TLV PHYSICAL AGENTS COMMITTEE
Herbert H. Jones. Central Missouri Stale University, Chairman
Peter A. Breysse, University of Washington Gerald V. Coles, Dept, of Puftl/c Health -- Australia Thomas Cummings, Dept of Health -- Ontario, Canada Irving H. Davis, Dept, of Health --- Michigan Ronald D. Dobbin. NIOSH LCDR Joseph J. Drozd. USN Dr. Man P. Heins, OSHA LCDR Richard Johnson, USN LTC. George S. Kush, USAF Edward J. Largent. OSHA William E. Murray, NIOSH Dr. Wordie H. Parr. NIOSH David H. Sliney, USAEHA LTC Robert T. Wangemann, USAEHA Thomas K. Wilkinson, USPKS-NIH
Any comments or questions regarding these limits should be addressed to:
Executive Secretary P.O, 80X 1937 Cincinnati, Ohio 45201
PREFACE
PHYSICAL AGENTS
These threshold limit values refer to levels of physical agents and represent conditions under which it is be* lieved (hat nearly all workers may be repeatedly exposed day after day without adverse effect. Because of wide variations in individual susceptibility, exposure of an oc casional individual at, or even below, the threshold limit may not prevent annoyance, aggravation of a pre-exist ing condition, or physiological damage.
These threshold limits are based on the best available information from industrial experience, from experimen tal human and animal studies, and when possible, from a combination of the three.
These limits are intended for use In the practice of industrial hygiene and should be interpreted and applied 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 physical 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 Un ited States of America.
These values are reviewed annually by the Committee on Threshold Limits for Physical Agents for revisions or additions, as further Information becomes available.
Notice of Intent -- At the beginning of each year, proposed actions of the Committee for the forthcoming year are issued in the form of a "Notice of Intent." This notice provides not only an opportunity (or comment, but solicits suggestions of physical agents to be added to the list. The suggestions should be accompanied by substantiating evidence.
As Legislative Code -- The Conference recognizes that the Threshold Limit Values may be adopted in legis lative codes and regulations. If so used, the intent of the concepts contained in the Preface should be maintained and provisions should be made to keep the list current.
55
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AP00043639
Repritft Permission -- This publication may be re printed provided that written permission is obtained from the Executive Secretary of the Conference and that this Preface be published in its entirety along with the Threshold Limit Values,
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 con ditions without exceeding a deep body temperature of 38*C (WHO technical report series #412, 1969 Health Factors Involved in Working Under Conditions of Hut Stress-, F. N. Oukes-Oobos and A. Henschel: "Develop ment of Permissible Heat Exposure Limits for Occupa tional Work," ASHRAE Journal, Vol. 15: No, 9, Sep tember 1973, pp. 57-62.)
Since measurement of deep body temperature is Im practical for monitoring the workers' heat load, the mea surement of environmental factors Is required which most nearly correlate with deep body temperature and other physiological responses to heat. At the present time Wat Bulb-Globe Temperature index (WBGT) is the simplest and most suitable technique to measure the en vironmental factors. WBGT values are calculated by the following equations:
1. Outdoors with solar load: WBGT - Q.7WB + 0.2GT + 0.1 06
2. Indoors or Outdoors with no solar load; WBGT = 0.7WB + 0.3GT
where:
WBGT Wet Bulb-Globe Temperature Index WB - Natural Wet-Bulb Temperature DB - Dry-Bulb Temperature GT > Globe Thermometer Temperature
56
The determination of WBGT requires the use of a black globe thermometer, a natural (static) wet-bulb thermom eter, and a dry-bulb thermometer.
TABLE 1
Permissible Heat Exposure Threshold Limit Values {Values are given in *C. WBGT)
Work Load
Work -- Rest Regime^
Light Moderate Heavy
Continuous work
30.0 26.7 25.0
75% Work -- 25% Rest, Each hour
50% Work -- 50% Rest, Each hour
30.6 28.0 25.9
31.4
2M
27.9
25% Work -- 75% Rest, Each hour
32.2 31.1
30.0
Higher heat exposures than shown in Table 1 are per missible If the workers have been undergoing medical surveillance and it has been established that they are
more tolerant to work In heat than the average worker. Workers should not be permitted to continue their work when their deep body temperature exceeds 3ff,0"C.
EVALUATION AND CONTROL
I. Measurement of the Environment
The instruments required are a dry-bulb, a natural wet-bulb, a globe thermometer, and a stand. The mea surement of the environmental factors shall be per formed as follows:
A. The range of the dry and the natural wet bulb ther mometer shall be -5*C to 50C with an accuracy of D.5*C. The dry bulb thermometer must be shielded from the sun and the other radiant surfaces of the envi ronment without restricting the airflow around the bulb. The wick of the natural wet-bulb thermometer shall be
57
\
AP00043640
kept wet with distilled water (or at least 112 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 ther mometer, covering the stem about one additional bulb length. The wick should always be clean and new wicks should be washed before 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 a0.5*C) must be fixed in the center of the sphere. The globe thermometer shall be exposed at least 25 minutes before it is read.
0. A stand shall be used to suspend the three thermom eters so mat they do not restrict free air flow around the bulbs, and the wet-bulb and globe thermometer are not shaded.
0. it is permissible to use any other type of temperature sensor that gives identical reading as that of a mercury thermometer under the same conditions.
E. The thermometers must be so placed that the read ings are representative of the condition where the men work or rest, respectively.
The methodology outlined above is more fully ex plained in the following publications:
1. "Prevention of Heat Casualties in Marine Corps Re cruits, 1955-1960, with Comparative Incidence Rates and Climatic Heat Stresses In other Training Catego ries," by Captain David Minard, MC. USN, Research Re port No. 4, Contract No. MRD05.0V0001.01, Naval Medical Research Institute, Bethesda, Maryland, 21 Feb ruary 1961.
2. "Heat Casualties In the Navy and Marine Corps.
1959-1962, with Appendices on the Field Use of the Wet
Bulb-Globe Temperature index," by Captain David Minard, MC, USN, and R. L. O'Brien, HMC, USN. Re
search Report No. 7, Contract No. MR o05.ovoooi.oi,
Naval Medical Research Institute, Bethesda, Maryland. 12 March 1964.
58
3. Minard, D.: Prevention of Heat Casualties /n Marine Corps Recruits. Military Medicine 126(4): 26V272, 1961.
II. Work Load Categories
Heat produced by the body and the environmental heat together determine the total heat load. Therefore, if work is to be performed under hot environmental condi tions, the workload category of each job shall be es tablished and the heat exposure limit pertinent to the work load evaluated against the applicable standard in order to protect the worker from exposure beyond the permissible limit.
A. The work load category may be established by rank ing each job into light, medium, and heavy categories on the basis of type of operation. Where the work load is ranked into one of said three categories, i.e.
(1) light work (up to 200 KcaJ/hr or 800 Btu/hr): e.g., sitting or standing to control machines, performing light hand or arm work,
(2) moderate work (200-350 Kcaf/hr or 800-1400 Btu/hr): e.g., walking about with moderate lifting and pushing,
(3) heavy work (350-500 Kcal/br or 1400-2000 Btu/hr): e.g., pick and shovel work,
the permissible heat exposure limit for that work load shall be determinedlroro Table 1.
8. The ranking of the job may be performed either by measuring the worker's metabolic rate while performing his job or by estimating his metabolic rate by the use of the scheme shown in Table 2. Tables available in the literature listed below and in other publications as well may also be utilized. When this method fs used the per missible heat exposure limit can be determined by Figure 1.
1. Per-Olaf Astrand and Kaare Rodahl: "Textbook of Work Physiology" McGraw-Hill Book Company, New York, San Francisco, 1970.
2. "Ergonomics Guide to Assessment of Metabolic and Cardiac Costs of Physical Work." Amer. tnd. Hya. Assoc. J.32: 560.1971.
3. Energy Requirements for Physical Work. Purdue
5G
AP0004364I
mk
Farm Cardiac Project. Agricultural Experiment Station. Research Progress Report No. 30.1961.
4. J. I/, S. A. Difrrrin and R. Passmore: "Energy. Work and Leisure." Heinemann Educational Books, Ltd., Lon don. 1967.
TABLE 2
Assessment of Work Load
Average values of metabolic rate during different ac tivities.
A. Body position and movement Sitting Slanding Walking
Walking up hill
Kcat./mln. 0.3 0.6
2.0-30
add 0.6 per meter (yard) rise
B. Type of Work
Average
Range
Kcal./min. Kcal./min.
Moderate work with the body: cleaning a floor, beat ing a carpet
Heavy work with the body: railroad track laying, dig ging, barking trees
Sample Calculation: Using a heavy hand tool on an assembly line
A. Walking along
2.0 Kcal./min.
B. Intermediate value between heavy
work with two arms and light work
with the Body
3.0 Kcal./min.
C. Add for basal metabolism
5.0 Kcal./min. 1.0 Kcal./min.
Total 6.0 Kcal./min.
Adapted from Lehmann. G. E., A. Muller and H. Sprtzer: Der Kalorienbedarf bei gewerblichar Arbeit. Arbeitsphysiol. U: 166,1950.
Hand work Work with one arm
light heavy
light
0,4 0.9
1.0
0.2-1.2 0.7-2.5
ill. 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
heavy
1.8
work area Is different from that of the rest area a time-
Work with both arms light
heavy
Work with body light
moderate heavy
veiy heavy
1.5 2.5
3.5 5.0 7.0 9.0
1.0-3.5 2.5-15.0
weighted average value should be used for both environ mental and metabolic heat.' When time-weighted average values are used the appropriate curve on Figure 11s the solid line labeled "continuous."
The time-weighted average metabolic rate (M) shall be determined by the equation:
Av. M (Mi) x fr) + (Ma) x (fe) + . . + (M.) x (u)
(ti) + (Ik) +---------+ (U)
Light hard work: writing, hand knitting
Where Mi Mz, M,, are estimated or measured metabolic
Heavy hand work: typewriting
rates for the various activities of the worker during the
Heavy work with one arm: hammering in nails (shoe maker, upholsterer)
total time period, ti, tz, t* are the elapsed times in min
utes spent at the corresponding metabolic rate as deter mined by a time study.
Light work with two arms: filing metal, planing I
The time-weighted average WBGT shall be deter
wood, raking of a garden
mined by the equation:
60 | 61
AP00043642
Av. WBGT (WBGTi) x (It) + (WBSTa) xb+ .. .+ (WBGT,) x (U)
(ti) t(h) + . . . +(U)
where WBGTi. WBGTi, WBGT. are calculated values of WBGT for the various work and rest areas occupied durIng total time periods, ti. ta, t. are the elapsed times in minutes spent in the corresponding areas which are de termined by a time study. Where exposure to hot envlmomenta) conditions is continuous for several hours or the entire work day, the time-weighted averages shall be calculated as hourly time-weighted average I.e., ti + U + .,. t, = 60 minutes. Where the exposure is Intermittent, the time-weighted averages shall be calculated as two-hour time-weighted averages, i.e., ti + t* + . , . U - 120 minutes.
The permissible exposure limits for continuous work are applicable where there is a work-rest regimen of a
5-day work week and an 8-hour work day with a short morning and afternoon break (approximately 15 minutes) and a longer lunch break (approximately 30 minutes). Higher exposure limits are permitted 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 temperatures.
It is a common experience that when the work on a job Is self-paced, the workers will spontaneously limit their hourly work load to 33-50% of their maximum physical performance capacity. They do this either by setting an appropriate work speed or by Interspersing unscheduled breaks. Thus the daily average of the workers' metabolic rate seldom exceeds 330 kcal/hr. However, within an 8-hour work shift there may be periods where the workers' hourly average metabolic rate will be higher.
f * ,j ;i j 'j
i, !
1 .j .i *i |j 4 j ? ; ij -j
\ :
' 1 ;
*
IV. Water and Salt Supplementation
During the hot season or when the worker Is exposed to artificially generated heat, drinking water shall be made available to the workers in such a way that (hey are stimulated to frequently drink small amounts, i.e.. one cup every 15-20 minutes (about 150 ml or 1/4 pint).
62
The water shafi be kept reasonably cool (TO*- I5"C or 50.0-60.fl*F) and shall be placed close to the work place 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 particularly during hot spells. If the workers are unacclimatized, salted drinking water shall be made available in a concentration of 0.1% (IgNaCI to 1.0 liter or 1 level tablespoon of salt to 15 quarts of water). The added salt shall be complete ly 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 condi tions. II special cothing is required for performing a par ticular lob and this clothing is heavier or it impedes sweat evaporation or has higher insulation value, the worker's heat tolerance is reduced, and hie permissible heat exposure limits indicated in Table 1 and Figure 1 are not applicable. For each job category where special clothing Is required, the permissible heat exposure limit shall be established by an expert. B. Acclimatization and Fitness: The recommended heat stress TLVs are valid for acclimated workers who are physically fit.
63
AP00043643
Adi
1
t:
IONIBN0 RAOIATION
The recommendations of the National Council on Radia tion Protection and Measurements (NCRP) are suggest ed as threshold limit vafejes to which nearly all workers may be exposed without adverse effects. The limits should be used as guides for the control of exposure and should not be regarded as fine lines between safe and dangerous levels. The underlying philosophy of radi ation protection Is to keep all exposures as tow as rea sonably achievable.
The two basic reference documents are as folfows:
a. "8asic Radiation Protection Criteria," NCRP Re port No. 39, issued January 15,1971.
b. "Maximum Permissible Body Burdens and Max imum Permissible Concentrations of Radionuclides in Air and in Water for Occupational Exposure," US Depart ment at Commerce. National Bureau of Standards Hand book 69, issued June 5,1959, with Addendum 1 Issued August 1063. 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, 7910 Woodmont Ave., Washington, 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 avail able information from experimental studies.
UmitinQ Apertures
The TLVs expressed as radiant exposure or irradlance In this section may be averaged over an aperture of 1 mm except for TLVs for the eye In the speclral range of 400-1400 nm, which should be averaged over a 7 mm limiting aperture (pupil); and except for all TLVs for wa velengths between 6.1-1 mm where the limiting aper ture Is 10 mm. No modification of the TLVs Is permitted for pupil sizes less than 7 mm.
65
1
i i i
\ 1
AP00043644
*1
The TIVs for "extended sources" apply to sources which subtend an angle greater than a (Table 5) which varies with exposure time. This angle Is not the beam divergence of the source.
Correction Factors A and B (CA and Ca)
The TIVs for ocular exposure in Tables 3 and 4 are to be used as given for ail wavelength ranges. The TIVs for wavelengths between 7D0 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 (C*) of five. For certain exposure times at wavelengths between 550 nm and 700 nm, correction factor (Cj) must be applied.
The TLVs for skin exposure are given in Table 6. The TLVs are to be increased by a factor (C>) as shown in Figure 2 for wavelengths between 700 nm and 1400 nm. To aid in the determination of TLVs for exposure durations requiring calculations of fractional powers Figures 3, 4, 5 and 6 may be used.
<fSTse) -
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.
I |
Repetitively Pulsed Users
Since there are few experimental data for multiple pulses, caution must be used in the evaluation of such exposures. The protection standards for irradiance or ra diant exposure In multiple pulse trains have (he following ilmlfadons.'
(1) The exposure from any single pulse In the train is limited to the protection standard for a single compara ble pulse.
(2) The average Irradiance for a group of pulses is limited to the protection standard as given in Tables 3, 4, or 6 of a single pulse of the same duration as the entire pulse croup.
(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 re duced as shown In Figure 6 for pulse durations less than 10~* second. For pulses of greater duration, the follow
ing formula should be followed:
66
{ i
\
AP00043645
C onoctioa fa c to r A (C^) TLV for intribeam (direct) viewinfl of User beam (400-700 nm).
AP00043646
!
k \
AP00043647
EXPOSURE DURATION ( x )
\
s
AP00043648
Hfire Sa -- TLV for extended sources or dffuse reflections of laser radiation (400-700 nm).
euue nocnrcM nvoucncr. mw (Hit
Figure f -- Multiplicative correction (actor for repetitively pulsed lasers having pulse durations less than 10~* 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.
i
74 75
11
AP00043649
Spectral Region
uvc
UVB
TABLE 3
Threshold Limit Value for Direct Ocular Exposures (Intrabeam Viewing) from a Laser Beam
Wave Lenoth
Exposure Time. (t) Seconds
TLV
200 nm to 280 nm
280 nm to 302 nm 303 nm 304 nm 30Snm
306 nm 307 nm 308 nm 309 ran 310 nm 311 nm 312 nm 313 nm 314 nm
10-*to3xt0* " " "
" "
"
3 mJ cnr*
3 4" 6 10
16 25 40 63 10 160 " 250 400 630
AP00043650
TABLE 3 (Cont.)
UVA 315 nm to 400 nm 10"* to 10
.561 J* cm-*
10 to 10*
1.0 J cm-*
..
.. 10* to 3 x 10*
1.0 mW cm'*
Light
400 nm to 700 nm 10-* to 1.8 X ir* 5 x io-'j cm-*
400 rm to 700 nm 1.8 x 10-* to 10
1.8 (V V t ) mJ cm-1
400 nm to 549 nm 10 to 10*
10 mJ cm-*
550 nm to 700 nm lOtoT,
1.8 (t/ VT") mJ cm-*
550 nm to 700 nm T, to 10*
f0c4 mJo cm-*
400 nm to 700 nm 10* to 3 x 10*
cm-*
iR-A
700 nm to 1049 nm 10'* to 1.8 x 1Q"` 5 CA x 10-7 J cm-*
3
700 nmto 1049 nm 1.8 x 10-* to 10*
1.8 C,( (V VT") mJ cnv
1050 nm to 1400 nm 10-*to10-*
5 x 10-* J cm-1
1050 nm to 1400 nm 10"* to 10*
9(t/ iTF ) mJ cm-1
700 nm to 1400 nm 10* to 3 x to*
320 C, MW cm-*
IR-B & C 1.4/*mto ICfVm 10-*to10-'
10-1 J cm*
"tt
i"t
10-* to 10 10 to 3 X 10*
0.56 Vl~ J cm~* 0.1 W cm-*
C., - Seefio. 2. C* - 1 Fw X = 400 to 549 nm; C. - 10* * - **" for X = 550 to
700 nm.
T, = 10 s tor i - 400 to549 nm;T, = 10 x
SSQtoTQQn.
for X =
Spectral Regton UV Light
IR-A
IR-fl 4 C
TABLE 4
Threshold Limit Values for Viewing a Diffuse Reflection ol a Laser Beam or an Extended Source Laser
Wave Length
Exposure Time, (t) Seconds
TLV
200 nm to 400 nm 400 nm to 700 nm
400 rtm to 549 nm 550 nm to 700 nm 550 nm to 700 nm 400 nm to 700 nm 700 nm to 1400 nm 700 nm to 1400 nm 700 nmto 1400 nm 1.4/i.m to 1 mm
10`* to 3 x 10* 10-* to 10 10(o 10* 10 to Ti T, to 10* 10* to 3 X 10* 10-Mo 10 10 to 10* 10* to 3 x 10* 1Q-* to 3 x 10*
Same as Table 3
10 ,4rT' J cm-1 sr'
21 J cnr* srl
3.B3 (1/ VT) J cm'* sr*
21 C* J cnr* sr*
2.1 Cat x 10~* W* cnr**srl
10 C,,
J* cm-** sr*
3.83 C4 (ty ITT) J cm-* sr*
0.64 C* W cm'* * sr'
Same as Table 3
Cj.C,. aadT, are Um same as in footnote w Table 3.
AP00043651
TABLE 5
Limiting Angle to Extended Source Which May Be Used tor Applying Extended Source TLVs
e Ouration(s)
10~* 10"* 10-*
nr*
10-*' 1Q~*
io-s to-* io-
1.0 10 10* 10* 10*
Angle a (modi
6.0 5.4 3.7 2.5 1.7 22 3.6 5.7 9.2 15 24 24 24 24
iytfiwii
a -l &
tS- Tg"l t-
nv a
X Ei5_ I CONOCO u
O 'l **
.e < oa
<
JB
J
WT-
?r
'= |
MICROWAVES
j These Threshold Limit Values refer to microwave en ergy in the frequency range of 300 MHz to 300 GHz and represent conditions under which it is believed that near-
! ly all workers may be repeatedly exposed without ad verse effect.
| Under conditions of moderate to severe heat stress,
the recommended values may need to be reduced.* Therefore, these values should be used as guides in she control of exposure to microwave energy and should not be regarded as a fine line between safe and dangerous levels.
Recommended Values:
The Threshold Limit Value for occupational exposure to microwave energy, where power density or field In tensity Is known and exposure time is controlled, is as follows:
! 1. For exposure to continuous wave (CW) sources, the i power density level shall not exceed 10 milliwatts per I square centimeter (mW/cm2) lor continuous expo
sure, and the total exposure time shall be limited to | an 8-hour workday. This power density is approxi
mately equivalent to a tree-space electric field strength of 200 volts-per-meter rms (V/m) and a
free-space magnetic field strength of 0.5 ampsre-perI meter rms (A/m).
J 2. Exposures to CW power density levels greater than
10 mW/cm2 are permissible up to a maximum of 25 mW/cm* based upon an average energy density of 1 milliwatt-hour per square centimeter (mWh/cm3) ; averaged over any 0.1 hour period. For example, at 25 mW/cm2. the permissible exposure duration is i approximately 2.4 minutes in any 0.1 hour period.
! 3. For repetitively pulsed microwave sources, the
average field strength or power density is calculated by multiplying the peak-pulse value by the duty cycle. The duty cycle is equal to the pulse duration in sec onds tlmss the pulse repetition rate in Hertz. Expo* I sure during an 3-hour workday shall not exceed the
f.'MumloRS, W.W.. "Hen Stress Due to R. Radiation." Proceedings of
IEEE. Vol. 57, NO. 2. NO. 1969. pp. 17V176.
!
f
AP00043652
tallowing values which are averaged over any 0.1 hour period:
Power Density Energy Density Mean Squared Electric Field Strength Mean Squared Magnetic Field Strength
lOmW/em* 1 mWh/cm* 40,000 V'/m* 0.25 A*/m*
4. Exposure is not permissible in CW or repetitively pulsed fields with an average power density In excess
of 25 mW/cm2 or approximate equivalent tree-space field strengths of 300 Wm or 0.75 A/m.
] 1
' 1 ` 1
NOISE
These threshold limit values refer io sound pressure
levels and durations of exposure that represent condi tions under which it is believed that nearly all workers may be repeatedly exposed without adverse effect on their ability to hear and understand normal speech. The medical profession has defined hearing Impairment as an average hearing threshold level in excess of 25 de cibels (ANSI-S3.6-196S) at 500, 1000, and 2000 Hz, and the limits which are given have been established to prevent a hearing loss in excess of this level. The values should be used as guides in the control of noise expo sure and, due to individual susceptibility, should not be regarded as fine lines between safe and dangerous levels.
It should be recognized that the application of the TLV for noise will not protect ad workers from the ad verse effects of noise exposure. A hearing conservation program with audiometric testing Is necessaiy when workers are exposed to noise at or above the TLV levels.
'i
Continuous or Intermittent
The sound level shall be determined by a sound level meter, conforming as a minimum to the requirements of
the American National Standard Specification 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 exceed that shown In Table 7.
These values apply to total duration ol exposure per working day regardless of whether mis is one continu ous exposure or a number of short-term exposures but does not apply to impact or Impulsive type of noise.
When the daily noise exposure is composed of two or more periods of noise exposure of different levels,
' j 5 !
j !
their combined effect should be considered, rather than the individual effect of each, if the sum of the following
fractions:
Ci C2 Ti * Ti
C% Tn
exceeds unity, then, the mixed exposure should be con sidered to exceed the threshold limit value, Ci indicates the total duration of exposure at a specific noise level, and Ti indicates the total duration of exposure permitted at that level. All on-the-job noise exposures of 80 dBA or greater shall be used in the above calculations.
Table 7 Threshold Limit Values
Duration per day Hours
16 8 4 2 1
1/2 1/4 1/8
Sound L< dBA"
60 85 90 95 100 105 110 115*
Ho exposuraio continuous orinWmittlanl In excess ol IIS dBA
a) Sound level in decibels as measured on a sound level meter, conformity) as a minimum to the require ments of the American National Standard Specifica tion for Sound Level Meters, SI .4 (1971) Type S2A, and set to use the A-weighted network with slow
meter response.
IMPULSIVE OB IMPACT NOISE
it Is recommended that exposure to Impulsive or im pact noise shall not exceed the limits listed in Table a or taken from Figure 7. No exposures in excess of 140 de cibels peak sound pressure level are permitted. Impul sive or impact noise is considered to be those variations in noise levels that involve maxima at intervals of greater
83
AP00043653
than one per second. Where the intervals are less than one second, It should be considered continuous.
Sound Level dB'* 140 130
120
Table 8 Threshold Limit Values Impulsive or Impact Noise
Permitted Number of impulses or
Impacts per day 100
1000 10,000
"Oscioels peak sound pressure level.
Figure 7 -- Threshold Limit Values for impulse/impact Noise.
84 85
AP00043654
ULTRAVIOLET RADIATION*
These threshold limit values refer to ultraviolet radiatlon in the spectral region between 200 and 400 nm and represent conditions under which it is believed that near* ly all workers may be repeatedly exposed without ad verse effect. These values for exposure of the eye or the
skin apply to ultraviolet radiation from arcs, gas, and vapor discharges, fluorescent, and incandescent sources, and solar radiation, but do not apply to ultravi-
olet lasers.* These values do not apply to ultraviolet radiation exposure of photosensitive individuals or of indivictuals concomitantly exposed to photosensitizing agents (Fitzpatrick, et at., eds., Sunlight and Man, Univ. Tokyo Press. Tokyo, Japan, 1974). These values should be used as guides in the. control of exposure to continuous sources where the exposure duration shall not be less than 0.1 sec.
ThBse values should be used as guides in the control of exposure to ultraviolet sources and should not be re* carded as a fine line between safe and dangerous levels.
Recommended Values:
The threshold limit value for occupational exposure to ultraviolet radiation incident upon skin or eye where Irradlance values are known and exposure time Is con trolled are as follows:
1. For the near ultraviolet spectral region (320 to 400 nm) total Irradiance incident upon the unprotected skin or eye should not exceed 1 mw/cm2 for periods greater than 109 seconds (approximately 16 minutes) and for exposure times less than 10* seconds should not exceed one J/cm*.
2. For the actinic ultraviolet spectral region (200 -- 315 nm), radiant exposure incident upon the unprotected skin or eye should not exceed the values given in Table 9 within an 8-hour period.
3. To determine the effective irradiance of a broadband source weighted against the peak of the spectral ef fectiveness curve (270 nm), the following weighting formula should be used:
[ | I I 'j j j
; i ;
where;
E,s " effective Irradiance relative to a monochromat ic source at 270 nm in W/cmz (J/s/cmz)
Ek, spectral irradiance In W/cmVnm
Sx - relative spectral effectiveness (unitless)
A\ * band width in nanometers
4. Permissible exposure time In seconds for exposure to actinic ultraviolet radiation incident upon the un protected skin or eye may be computed by dividing 0.003 J/cm* by E& in W/cma. The exposure time
may also be determined using Table 10 which pro vides exposure times corresponding to effective Irradiances In *iW/cm*.
TABLE 9
Relative Spectral Effectiveness by Wavelength
Wavelength (nm)
200 210 220 230 240 250 254
260 270 280 290 300 305
310 315
TLV (mJ/cmzr*
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 0.86 0.64
0.30 0.06 0.015 0.003
`See Lassr TLVs.
"lm J/tm* - 10-1 J/cm*
87
AP00043655
TABLE 10
Permissible Ultraviolet Exposures
Duration of Exposure
Per Pay
Effective Irradianca, E^r toW/cm8)-**
8 hrs.............................................................. 4 hrs..............................................................
0.1
0.2
2 firs..............................................................
0.4
1 hr................................................................
0.8
30 min...........................................................
1.7
15 min............................................
10 min......................................................
5
5 min........................................................ 10
1 mlrr........................................................ 50
30 sec...................................................... 100
10 sec...................................................... 300
1 sec......................................................... 3,000
0.5 sec........................................................8.000
0.1 sec......................................................30.000
All the preceding TLV's 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.
"lMW/cm* 10-*W;cm*
3.3
Figure t --Threshold Limit Values for Ultraviolet Radiation
Conditioned (tanned) individuals can tolerate skin ex posure in excess of the TlV without erythemal effects. However, such conditioning may not protect persons against skin cancer.
NOTICE OF INTENDED CHANGES (lor 1978)
These physical agents, with their corresponding val ues, comprise those for which either a limit has been proposed for the first time, or lor 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 one year. If after one year no evidence comes to light that questions the appropriateness of the values herein the values will be reconsidered tor the "Adopted" list.
88 89
\(
AP00043656
NOTICE OF INTENT TO ESTABLISH THRESHOLD LIMIT VALUES
LIGHT AND NEAR-INFRARED RADIATION
Ttiesa Threshold Limit Values refer to visible and near-infrared radiation in the wavelength range of 400 nm to 1400 nm and represent conditions under which it is believed that nearly all workers may be exposed with out 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.
Recommend*# Values:
The Threshold Limit Value for occupational exposure to broad-band light and near-infrared radiation for the eye apply to exposure fn any eight-hour workday and require knowledge of the spectral radiance (U) and total irradlance (E) of the source as measured at the posi tion^) of the eye of the worker. Such detailed spectral data of a white light source Is generally only required If the luminance of the source exceeds 1 ed cm'3. At lu minances less than this value the TLV would not be ex ceeded.
TheTLV's are:
1. To protect against retinal thermal Injury, the spectral radiance of the lamp weighted against the function R (Table 11) should not exceed:
140C
ft
lURxAAsl/at
400
(i)-
where Lk is in W cm-* sr_1 and t is the viewing duration (or pulse duration If the lamp is pulsed) lim
ited to 1 >us 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 in stance, at a viewing distance r - 100 cm from a tubular lamp of length t - 50 cm, the viewing 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 ra-
90
dtince of the lamp weighted against the blueWfght hazard function B*. (Table 11) should not exceed:
'JjJ Li t 8X to. =s 100 Jem-2 sr' (t * 10*s)
(3a)
1400
J u Bi ix * 10-J Wcm*2 sr1 (t > 10s)
(3b)
For a source radiance L which exceeds 2 mW cm*2
sr' in the blue spectral region, the permissible ex
posure duration
In seconds is simply:
U " 100 J cm-* srVL (blue)
(4)
The latter limits are greater than the maximum per missible exposure limits tor 440 nm laser radiation (see Laser TLV) because a 2-3 mm pupil Is assumed rather than a 7 mm pupil for the Laser TLV.
3, Infrared Radiation: To avoid possible delayed effects
upon the lens of the eye (cataractogenesisj, the infra
red radiation (A > 770 nm) should be limited to 10
rnWcm*2. For an Infrared heat lamp or any near-ln*
frarad source where a strong visual stimulus is ab
sent. the near Infrared (770-1400 nm) radiance as
viewed by the eye should be limited to:
1400
U AA - 0.6/a
(5)*
for extended duration viewing conditions. This limit
is based upon a 7 mm pupil diameter.
'Formulae (i) and (2) are empirical and an not. strictly speaking, di
mensionally cornet. To make the formulae dimensionally correct, one
would have to Insert a dimensional correction factor k In the right hand
numerator in esen formula. For formula (1) this would be k, - 1 W
rid
sr|, and lor formula (5) k, - 1 W rad/<cm`sr),
91
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TABLE 11
SPECTRAL WEIGHTING FUNCTIONS FOR ASSESSING RETINAL HAZARDS FROM BROAD -- BANO OPTICAL
SOURCES
Wavelength
fnm)
400 405
410 415 420 425 430
435 440 445 450 455 460 465
470 475 480 465 490 495 500-600 600-7Q0 700-1049 1050-1400
Blue-Ught Hazard Function
Bi
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
0.001
o.oot
0.001
Burn Hazard Function
Rjl
1.0 2.0 4.0 0.0 9.0 9.5 9.8 10 10 9.7 9.4 9.0 8.0 7.0 8.2 5.5 4.5 4,0 2.2 1,8 1.0 1.0 1 QMIOO-UrHKI
0.2
AIRBORNE UPPER SONIC AND ULTRASONIC ACOUSTIC RADIATION
These threshold limit values refer to sound pressure levels that represent conditions under which it Is be lieved that nearly ail workers may be repeatedly exposed without adverse effect The values listed in Table 15 should be used as guides in the control of noise expo sure and, due to Individual susceptibility, should not be regarded as fine lines between safe and dangerous
levels. The levels for the third octave bands centered below 20 kHz are below those which cause subjective effects. Those levels for 1/3 octaves above 20 kHz are for prevention of possible hearing losses from subharmonics of these frequencies.
TABLE 12 Permissible Ultrasound Exposure Levels
Mid-Frequency ol Third-Octave Band
kHz
10 12.5 16 20 25 31.5 40 50
One-Third Octave -- Band Level in dB reference 0.0002 dynes/cm2
80 80 80 105 110 115 115 115
92 93 \ s
AP00043658
PHYSICAL AGENTS UNDER STUOT
These agents comprise those which the Physical Agents Committee of AC6IH proposes to study during this year to determine the feasibility of establishing pro posed TLVs in 1979. Comments and suggestions, ac companied by substantive evidence, are solicited.
1. Radiofrequency Radiation. Specifically, that portion
of the spectrum from 10 MHz to 100 MHz.
2. Extremely Lour Frequency (ELF) Radiation. Specifical ly. that portion of the spectrum from 0 to 300 Hz.
3. Magnetic Fields, Both pulsed and continuous.
4. Laser Radiation, Specifically ultraviolet radiation for pulsed exposures, and repetitively pulsed light and infrared-A laser ex posures.
5. Ultrasonic Enargy. Specifically, acoustic energy at frequencies above 10 kHz.
6. Vibration. Segmental and whole-body.
7. Cold Stress.
8. Pressure variations.
i * i
The American Conference of Governmental Industrial Hy gienists was organized in 1938 by a group of govern mental industrial hygienists who desired a medium lor the free exchange of Ideas, experiences and the promo tion of standards and techniques in industrial health. The Conference is not an official Government Agency.
It is an organization devoted to the development of ad ministrative and technical aspects of worker health pro tection. The association has contributed substantially to the development and improvement of official industrial health services to Industry and labor. The committees on industrial Ventilation and Threshold Limit Values are rec ognized throughout the world for their expertise and contributions to industrial hygiene.
Membership is limited to professional personnel in gov ernmental agencies or educational institutions engaged in occupational safety and health programs. The more than 1800 members from across the United States and around the world give the organization an International scope.
i
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