Document mqyXxaOBRG70pYRmb0MYrwDrO
FMSI 02912
Threshold Limit VaIues
of Airborne Contaminants
AND INTENDED CHANGES
Adopted By ACGIH
For 1970
FMSI 02914
Copyright 1970, by American Conference of Governmental Industrial Hygienists.
The American Conference of Governmental Industrial Hygienists will welcome requests for permission to republish or reprint these Threshold Limit Values. Requests for such permission should be directed to the SecretaryTreasurer, 1014 Broadway, Cincinnati, Ohio 45202.
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Documentation of Threshold Limit Values. A separate companion piece to the 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 contains 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 Documentation be consulted when the TLVs are being used.
Information concerning the availability of copies of the Documentation of Threshold Limit Values should be directed -to the Secretary-Treasurer.
FMSI 02915
PREFACE THRESHOLD LIMIT VALUES FOR 1970
Threshold limit values refer to airborne concentrations of substances and represent conditions under which it is believed that nearly all workers may be repeatedly exposed day after day without adverse effect. Because of wide variation in individual susceptibility, however, a small percentage of workers may experience discomfort from some &'Ubstances at concentrations at or below the threshold limit, a smaller percentage may be affected more seriously by aggravation of a pre-existing condition or by development of an occupational illness.
Simple tests are now available (J. Occup. Med. 9, 537, 1967; Ann. N.Y. Acad. Sci., 151 Art. 2, p. 968, 1968) that may be used to detect those individuals hypersusceptible to a variety of industrial chemicals (respiratory irritants, hemolytic chemicals, organic isocyanates, carbon disulfide). These tests may be used to screen out by appropriate job placement the hyperreactive worker and thus in effect improve this "coverage" of the TLVs.
Threshold limit values refer to time-weighted concentrations for a 7 or 8-hour workday and 40-hour workweek. They should be used as guides in the control of health hazards and should not be used as fine lines between safe and dangerous concentrations. (Exceptions are the substances listed in Appendices A and E and those substances designated with a "C" or Ceiling value, Appendix C.)
Time-weighted av. .:~~rmit excursions abovEl thfi! limit provided they are compensatea by equivalent excursions below the limit during the workday. In some instances it may be permissible to calculate the average concentration for a workweek rather than for a workday. The degree of permissible excursion is related to the magnitude of the threshold limit value of a particular substance as given in Appendix C. The relationship between threshold limit and permissible excursion is a rule of thunib and in certain cases may not apply. The amount by which threshold limits may be exceeded for short periods without injury to health depends upon a number of factors such as the nature of the contaminant, whether very high concentrations - even for short periods - produce acute poisoning, whether the effects are cumulative, the frequency with which high concentrations occur, and the duration of such periods. All factors must be taken into consideration in arriving at decision as to whether a hazardous condition exists.
1
FMSI 02916
Threshold limits are based on the best available information from industrial experience, from experimental human and animal studies, and, when possible, from a combination of the three. The basis on which the values are established may differ from substance to substance; protection against impairment of health may be a guiding factor for some, whereas reasonable freedom from irritation, narcosis, nuisance or other forms of stress may form the basis for others.
The committee holds to the opinion that limits based on physical irritation should be considered no less binding than those based on physical impairment. There is increasing evidence that physical irritation may initiate, promote or accelerate physical impairment through interaction with other chemical or biologic agents.
In spite of the fact that serious mJury is not believed likely as a result of exposure to the threshold limit concentrations, the best practice is to maintain concentrations of all atmospheric contaminants as low as is practical.
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 or air pollution nuisances, (3) in estimating the toxic potential of continuous uninterrupted exposures, (4) as proof or disproof of an existing disease or physical conditions, 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-weighted average concentration provides the most satisfactory, practical way of monitoring airborne agents for compliance with the limits, there are certain substances for which it is inappropriate. In the latter group are substances which are predominantly fast acting 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 compliance with the limits for each group must differ; a single brief sample, that is applicable to a "C" limit, is not appropriate to the time-weighted limit; here, a sufficient number of samples are needed to permit a time-weighted average concentration throughout a complete cycle of operations or throughout the work shift.
2
FMSI 02917
Whereas the ceiling limit places a definite boundary which concentrations should not be permitted to exceed, the timeweighted 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 C. It should be noted that the same factors are used by the Committee in making a judgment whether to include or exclude a substance for a 11C" listing.
"Skin" Notation. Listed substances followed by the designation "Skin" refer to the potential contribution to the over-all 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 mixtures of two or more substances. A brief discussion of basic considerations involved in developing threshold limit values for mixtures, and methods for their development, amplified by specific examples are given in Appendix B.
Nuisance Dusts. In contrast to fibrogenic dusts which cause scar tissue to be formed in lungs when inhaled in excessive amounts, so-called "nuisance" dusts have a long history of little adverse effect on lungs and do not produce significant organic disease or toxic effect when exposures are kept under reasonable control. The nuisance dusts have also been called (biologically) "inert" dusts, but the latter term is inappropriate to the extent that there is no dust which does not evoke some cellular response in the lung when inhaled in sufficient amount. However, the lung-tissue reaction caused by inhalation of nuisance dusts has the following characteristics: 1) The architecture of the air spaces remains intact. 2) Collagen (scar tissue) is not formed to a significant extent. 3) The tissue reaction is potentially reversible.
Excessive concentrations of nuisance dusts in the workroom air may seriously reduce visibility (iron oxide), may cause unpleasant deposits in the eyes, ears and nasal passages (Portland Cement dust), or cause injury to the skin or mucous membranes by chemical or mechanical action per se or by the rigorous skin cleansing procedures necessary for their removal.
3
FMSt 02918
A threshold limit of 10mg/M3; or 30 mppcf, of total dust < 1% Si02, whichever is less, is recommended for 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 at 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 "inert" particulates are given in Appendix D.
Simple Asphyxiants - "Inert" Gases or Vapors. A number of gases and vapors, when present in high concentrations in air, act primarily as simple asphyxiants without other significant physiologic effects. A TLV may not be recommended for each simple asphyxiant because the limiting factor is the available oxygen. The minimal oxygen content should be 18 percent by volume under normal atmospheric pressure (equivalent to a partial pressure, pOz of 135 mm Hg). Atmospheres deficient in Oz do not provide adequate warning and most simple asphyxiants are ordorless. Several simple asphyxiants present an explosion hazard. Account should be taken of this factor in limiting the concentration of the asphyxiant. Specific examples are listed in Appendix E.
Physical Factors. It is recognized that such physical factors as heat, ultraviolet and ionizing radiation, humidity, abnormal pressure (altitude) and the like may place added stress on the body so that the effects from exposure at a threshold limit may be altered. Most of these stresses act adversely to increase the toxic response of a substance. Although most threshold limits have built-in safety factors
I' to guard against adverse effects to moderate deviations from
normal environments, the safety factors of most substances
I are not of such a magnitude as to take care of gross deviations. For example, continuous work at temperatures above
I 900F or over-time extending the workweek more than 25%, might be considered gross deviations. In such instances judgment must be exercised in the proper adjustments of I the threshold limit values.
"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 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.
As Legislative Code. The Conference recognizes that the TLVs may be adopted in legislative codes and regulations. If so used, the intent of the concepts contained in the Preface
4
FMSI 02919
should be maintained and provisions should be made to keep the list current. These values are reviewed annually by the Committee on Threshold Limits for revision or additions, as further information becomes available.
Reprint Permission. This publication may be reprinted provided that written permission is obtained from the Secretary-Treasurer of the Conference and that it be published in its entirety.
5
FMSI 02920
Substance
ADOPTED VALUES
(In Alphabetical OrderI
ppma)
mg/M3b)
Abate ........... o Acetaldehyde .................... Acetic acid .................. Acetic anhydride ................ 0 Acetone ...................... Acetonitrile .................. 0 Acetylene ..................... 0. Acetylene dichloride, see 1, 2-
Dichloroethylene ............... Acetylene tetrabromide ...... Acrolein .. 0 Acrylamide-Skin ................. Acrylonitrile-Skin ................. Aldrin-Skin o Allyl alcohol-Skin ..... 0 AllyI chloride ............... **C Allyl glycidyl ether (AGE) ....... Allyl propyl disulfide ...........
Alundum (Al203) ...... 2-Aminoethanol, see Ethanolamine . 0 0 2-Aminopyridine ... o ** Ammonia . . . . . . . . . . . . . . o Ammonium sulfamate (Ammate) .... n-Amyl acetate ............ sec-Amyl acetate .............
Aniline-Skin ........... Anisidine (o, p-isomers)-Skin ... 0 Antimony & compounds (as Sb) ANTU (alpha naphthyl thiourea) .. Argon o Arsenic & Compounds (as As) ... Arsine ................. 0 o. Azinphos-methyl-Skin ...... Barium (soluble compounds) ..... C Benzene (benzol)-Skin ....... Benzidine-Skin ....... p-Benzoquinone, see Quinone ... Benzoyl peroxide .... 0 Benzyl chloride ..... Beryllium ... Biphenyl, see Diphenyl .... Bisphenol A, see Diglycidyl ether Boron oxide ......... Boron tribromide ......
C Boron trifluoride ............ Bromine ...................
* Bromine pentafluoride .......... Bromoform-Skin ...... Butadiene (1, 3-butadiene) ........ Butanethiol, see Butyl mercaptan . 2-Butanone ........ 2-Butoxy ethanol (Butyl Cellosolve)
-Skin ..... Butyl acetate (n-butyl acetate) .
200 10 5
1, 000 40 E
1 0.1 20
2 1 10 2
o. 5
50 100 125
5
E 0. 05.
25
1 1 0.1 0.1 0.5 1, 000
200 50
150
15 360 25 20 2,400 70
14 0.25
o. 3
45 0.25 5 3 45 12 D
2 35 15 525 650 19 0.5 0.5 0.3
0.5 0.2 0.2 0.5 80 Al
5 5 0.002
15 10 3 0.7
o. 7
5 2,200
590
240 710
a) Parts of vapor or gas per million parts of contaminated air by volume at 25C and 760 mm. Hg pressure.
b) Approximate milligrams of particulate per cubic meter of air.
** See Notice of Intended Changes
Capital letters refer to Appendices.
6
FMSI 02921
Substance
ppma)
sec-Butyl acetate .... tert-Buty1 acetate ............ Buty1 alcohol ............. o sec-Butyl alcohol ......... o tert-Buty1 alcohol ........ 0 C Butylamine-Skin ........
200 200 100 150 100
5
C tert-Butyl chromate (as Cr03) - Skin n-Butyl glycidyl ether (BGE) ..
* Buty1 mercaptan .......... p-tert-Butyltoluene ......
50
o. 5
10
Cadmium (Metal dust and soluble salts)
*C Cadmium oxide fume (as Cd) ...
Calcium carbonate ........
Calcium arsenate ....... 0
Calcium oxide ............ o ** Camphor (Synthetic) ..........
2
Carbaryl (Sevin ) .
Carbon black ........... Carbon dioxide ....... 0 Carbon disulfide-Skin ..... Carbon monoxide ..... Carbon tetrachloride-Skin .....
5,000 20 50
10
Cellulose (paper fiber) ....
Chlordane-Skin .....
Chlorinated camphene-Skin ......
Chlorinated diphenyl oxide ..... * Chlorine . o
Chlorine dioxide ...... C Chlorine trifluoride ..... C Chloroacetaldehyde .......
1 0.1 0.1
1
oc:-Chloroacetophenone (phenacylchloride) .........
Chlorobenzene (monochlorobenzene) . o
0.05 75
o-Chlorobenzylidene malononitrile (OCBM) ....
Chlorobromomethane .....
0.05 200
2-Chloro-1, 3-butadiene, see
Chloroprene ...........
Chlorodiphenyl (42% Chlorine) - Skin
Chlorodiphenyl (54% Chlorine) - Skin .
1- Chloro, 2, 3-epoxypropane, see
Epichlorhydrin .....
2-Chloroethanol, see Ethylene
chlorohydrin ..........
Chloroethylene, see Vinyl choride . C Chloroform (trichloromethane) 0
1-Chloro-1-nitropropane . Chloropicrin ....... o
50 20 Oo1
Chloroprene (2-chloro-1, 3-butadiene) -Skin .............
25
Chromic acid and chromates (as CrOg)
Chromium, sol. chromic, chromous
salts as Cr ....... o
Metal & insol. salts . o
Coal tar pitch volatiles (benzene
soluble fraction) anthracene, BaP,
phenanthrene, acridine, chrysene,
pyrene) ................
mg/M3 b)
950 950 300 450 300
15 Oo1 270 1.5 60 00 2 Oo1
D 1 5
5
3o5 9,000
60 55 65
D
0.5
o. 5
0.5
3
0.3 0.4 3
0.3 350
0.4 1,050
1 0.5
240 100
0.7
90 Oo1
0.5 1
o. 2
1970 Addition See Notice of Intended Changes
7
FMSI 02922
Substance
Cobalt, metal fume & dust .. Copper fume ..........
Dusts and Mists ..... Corundum (Al203) ........ Cotton dust (raw) ......... Crag herbicide ...... Cresol (all isomers) - Skin .. Crotonaldehyde .......... Cumene-Skin ............ Cyanide (as CN)-Skin ....... *Cyanogen ............. Cyclohexane ............ Cyclohexanol ........... Cyclohexanone ........ Cyclohexene ...... Cy.clopentadiene .......... 2, 4-D ....... DDT-Skin ..... DDVP, see Dichlorvos . Decaborane-Skin .... Demeton -Skin .. Diacetone alcohol (4-hydroxy-
4-methyl-2-pentanone) . 1, 2-Diaminoethane, see Ethylene-
diamine ........ Diazomethane ........ Diborane ......... C 1, 2-Dibromoethane (ethylene
dibromide)-Skin .... Dibutyl phosphate ................ .. Dibutylphthalate .... *C Dichloroacetylene . C o-Dichlorobenzene . p-Dichlorobenzene .
Dichlorodifluoromethane .. 1, 3-Dichloro-5, 5-dimethyl hydantoin 1, 1-Dichloroethane ..... 1, 2-Dichloroethane ..... 1, 2-Dichloroethylene .. C Dichloroethyl ether-Skin . Dichloromethane, see Methylene-
chloride ... Dichloromonofluo;~omethane .. C 1, 1-Dichloro-1-nitroethane 1, 2-Dichloropropane, see Pro-
pylenedichloride .. Dichlorotetrafluoroethane . Dichlorvos (DDVP)-Skin .. Dieldrin-Skin .... Diethylamine ..... Diethylamino ethanol-Skin .. **C Diethylene triamine-Skin .. Diethylether, see Ethyl ether . Difluorodibromomethane . C Diglycidyl ether (DGE) ... Dihydroxybenzene, see Hydroquinone Diisobutyl ketone Diisopropylamine-Skin
5 2 50
10 300
50 50 300 75
0,05
50
0.2 0.1
25 1
0.1 50 75 1,000
100 50
200 15
1,000 10
1,000
25 10 10
100 0,5
50 5
mg/M3b)
0.1 0.1 1 D 1 15 22 6 245 5
1,050 200 200
1, 015 200 10 1
0,3 0.1
240
0.4 0.1
190 5 5 0.4
300 450 4,950
0.2 400 200 790
90
4,200 60
7,000 1 0.25
75 50 42
860 2.8
290 20
1970 Addition See Notice of Intended Changes
8
FMSI 02923
Substance
ppma)
Dimethoxymethane, see Methylal .. Dimethyl acetamide-Skin ... Dimethylamine Dimethylaminobenzene, see Xylidene
10 10
Dimethylaniline (N-dimethylaniline)Skin .......
5
Dimethylbenzene, see Xylene ...
Dimethyl 1, 2-dibromo-2, 2-dichloroethyl phosphate, (Dibrom)
Dimethylformamide-Skin 2, 6-Dimethylheptanone, see
10
Diisobutyl ketone .. 1, 1-Dimethylhydrazine-Skin ..
o. 5
Dimethylphthalate Dimethylsulfate-Skin .. Dinitrobenzene (all isomers)-Skin
1
Dinitro-o-cresol-Skin .
Dinitrotoluene-Skin . Dioxane (Diethylene dioxide)-Skin ,
Diphenyl , ... Diphenyl amine . , , . ,
100 0.2
Diphenylmethane diisocyanate (see
Methylene bisphenyl isocyanate
(MDI) ......................... ..
Dipropylene glycol methyl ether-Skin . 100
Di-sec, octyl phthalate (Di-2ethylhexylphthalate) ..
Emery .........
* Endosulfan (Thiodan )-Skin . ,
Endrin-Skin .... Epichlorhydrin-Skin . . EPN-Skin. ...................... 0 ... D 1, 2-Epoxypropane, see Propylene-
oxide ........
~---
5
2, 3-Epoxy-1-propanol, see Glycidol. Ethane .... ,
E
Ethanethiol, see Ethylmercaptan . Ethanolamine .... , 2-Ethoxyethanol-Skin .. , 2-Ethoxyethylacetate (Cellosolve
acetate)-Skin .. , . , , Ethyl acetate .... Ethyl acrylate-Skin ... Ethyl alcohol (ethanol) , .. , Ethylamine .... Ethyl sec-amyl ketone (5-methyl-
3-heptanone) ......
Ethyl benzene .. , Ethyl bromide .... Ethyl butyl ketone (3-Heptanone) . ,
Ethyl chloride . , ..... Ethyl ether ..... , Ethyl formate ......... Ethyl mercaptan ..... Ethyl silicate .......... Ethylene ........ , . , Ethylene chlorohydrin-Skin .... ,
3 200
100 400
25 1, 000
10
25 100 200
50 1,000
400 100
o. 5
100 E 5
mg/M3b)
35 18
25
3 30
1 5 5 1 0,2 1. 5 360 1 10
600
5 D 0.1 0.1 19
Q.5
6 '140
540 1,400
100 1,900
18
130 435 890 230 2,600 1,200 300
1 850
16
* 1970 Addition
See Notice of fotended Changes
9
FMSI 02924
Substance
Ethylenediamine ... , ..... , Ethylene dibromide, see 1, 2-
Dibromoethane ........... Ethylene dichloride, see 1, 2-
Dichloroethane ..... -... C Ethylene glycol dinitrate and/or
Nitroglycerin-Skin .... , Ethylene glycol monomethyl ether
acetate, see Methyl cellosolve acetate ......... , Ethylene imine-Skin ..... Ethylene oxide ..... Ethylidlne chloride, see 1, 1-Di-
chloroethane .... , , , N-Ethylmorpholine-Skin , ..... , ..
Ferbam ... , ... Ferrovanadium dust . , . , .. Fibrous glass ..... , Fluoride (as F) . , ..... , , Fluorine .. , .... , , Fluorotrichloromethane . , , , . , , , **C Formaldehyde .. , , .. ,
Formic acid . , . , .. Furfural-Skin .. Furfuryl alcohol , ... , , . , , Gasoline ......... , Glycerine mist , ... Glycidol (2, 3-Epoxy-1-propanol) . Glycol monoethyl ether, see 2-
Ethoxyethanol .. , , ... , Graphite, (Synthetic) ... Guthion, see Azinphosmethyl . , Gypsum .... , . , ... Hafnium .......... Helium ........ Heptachlor-Skin ...... Heptane (n-heptane) .. Hexachloroethane-Skin . Hexachloronaphthalene-Skin . Hexane (n-hexane) , 2-Hexanone ...... Hexane (Methyl isobutyl ketone).
sec-Hexyl acetate .... Hydrazine-Skin ... Hydrogen .... Hydrogen bromide ... C Hydrogen chloride . Hydrogen cyanide-Skin .. Hydrogen fluoride Hydrogen peroxide . , Hydrogen selenide .. Hydrogen sulfide .... Hydroquinone . * lndene .....
10
0.5 50
20
0.1 1, 000
5 5 5
50
50
E
500 1
500 100 100
50 1
E 3 5
10 3 1 0.05
10 10
mg/M3b)
25
1 90
94 15
1 D 2.5 0.2 5,600
6 9
20 200
A3 D 150
D
D
o. 5
0,5 2,000
10 0.2 1, 800 410 410 300 1.3
10
7 11
2 1.4 0.2 15 2 45
d) An atmospheric concentration of not more than 0.02 ppm, or personal protection may be necessary to avoid headache.
1970 Addition
** See Notice of Intended Changes
10
FMSI 02925
Substance
Indium and compounds, as In ....
C Iodine ........... Iron oxide fume ......... Iron salts, soluble, as Fe ....
Isoamy1 acetate ......... Isoamyl alcohol ..... Isobuty1 acetate ........ Isobutyl alcohol ....
Isophorone , ......... Isopropyl acetate ...... Isopropyl alcohol .......... Isopropy!amine ................... . Isopropylether ........ Isopropyl glycidyl ether (IGE} .
Kaolin ................
Ketene ..........
Lead ............. Lead arsenate .... Limestone ...... Lindane-Skin .......... Lithium hydride ........
L. P. G. (Liquified petroleum gas} .... Magnesite ......... Magnesium oxide fume .... Malathion-Skin ....... Maleic anhydride ...... C Manganese and compounds, as Mn
Marble ......
** Mercury-Skin .....
** Mercury (organic compounds)-Skin .. .
Mesityl oxide ..................... .
Methane .......................... . Methanethiol, see Methyl mercaptan .. Methoxychlor .................... . 2-M~thoxyethanol, see Methyl
cellosolve....................... .
Methyl acetate .................... . Methyl acetylene (propyne).......... . Methyl acetylene-propadiene mixture
(MAPP) ......................... . Methyl acrylate-Skin ............... . Methylal (dimethoxymethane) ....... . Methyl alcohol (methanol) .......... . Methylamine ...................... . Methyl amyl alcohol, see Methyl
isobutyl carbinol. ................ .
* Methyl isoamyl ketone ............. .
Methyl (n-amyl) ketone (2-Heptanone).
C Methyl bromide-Skin ............... . Methyl butyl ketone, see 2-Hexanone . Methyl cellosolve-Skin ............. . Methyl cellosolve acetate-Skin ...... .
**C Methyl chloride ................... . Methyl chloroform ................. Methylcyclohexane ................. Methylcyclohexanol ................ .
0.1
100 100 150 100
25 250 400
5 500
50
o. 5
1,000
0,25
25
E
200 1,000
1,000 10
1,000 200 10
100 100 20
25 25 100 350 500 100
mg/M3b)
0.1 1 10
1
525 360 700 300 140 950 980
12 2,100
240
D
0.9 0.2 0.15
D
0.5 0,025 1,800 D 15 15 1 5 D 0.1 0.01 100
15
610 1,650
1,800 35
3,100 260 12
475 465 80
80 120 210 1,900 2,000 470
1970 Addition See Notice of Intended Changes
11
FMSI 02926
Substance
o-Methylcyclohexanone-Skin ........ Methyl ethyl ketone (MEK), see
2- Butanone ................. Methyl formate ................ Methyl iodide - Skin ............. Methyl isobutyl carbinol-Skin ...... Methyl isobutyl ketone, see Hexane ... Methyl isocyanate - Skin ......... * Methyl mercaptan ................ Methyl methacrylate ............. Methyl propyl ketone, see 2-Pentanone C Methyl silicate ................... C cc Methyl styrene ................. C Methylene bisphenyl isocyanate (MDI) Methylene chloride (dichloromethane) . Molybdenum (soluble compounds) ...
(insoluble compounds) .. Monomethyl aniline-Skin .......... C Monomethyl hydrazine-Skin ...... Morpholine-Skin ............. Naphtha (coal tar) ..............
Naphthalene ............ f3 -Naphthylamine .............. Neon ................ Nickel carbonyl ............... Nickel, metal and soluble cmpds, as Ni Nicotine- Skin ...... , .... , . , Nitric acid . , , .. , .............. . Nitric oxide ................ JrNitroaniline-Skin ........... Nitrobenzene-Skin ............. JrNitrochlorobenzene-Skin ....
Nitroethane ................ Nitrogen ................... C Nitrogen dioxide ................. Nitrogen trifluoride ............... Nitroglycerin-Skin ............ Nitromethane .................. 1-Nitropropane ................ 2-Nitropropane .................... . N-Nitrosodimethylamine (dimethyl-
nitrosoamine)-Skin ........ Nitrotoluene-Skin ........ Nitrotrichloromethane, see
Chloropicrin .. , ......... Nitrous oxide ............ Octachloronaphthalene-Skin ........ . *Octane.................... * Oil mist, particulate ............. * Oil mist, vapor .............. Osmium tetroxide ............... Oxalic acid ................. Oxygen difluoride ................. Ozone .......................... Paraquat-Skin ...................
ppma)
100
100 5
25
0.02 0.5 100
5 100
0.02 500
2 0.2 20 100 10
E 0.001
2 25
1 1
100 E 5 10 0.2
100 25 25
5
E
400
i) A3
0.05 0.1
h) As sampled by method that does not collect vapor. i) According to analytically determined composition.
1970 Addition See Notice of Intended Changes
mg/M3b)
460
250 28 100
0.05 1 410
30 480
0.2 1,740
5 15 9 0.35 70 400 50 A1
0.007 1 0.5 5 30 6 5 1 310
9 29
2 250
90 90
A1 30
0.1 1,900
sh
0.002 1 0.1 0.2 0.5
12
FMSI 02927
Substance
Parathion-Skin .................... Pentaborane ...................... . Pentachloronaphthalene-Skin ....... . Pentachlorophenol-Skin ............ Pentaerythritol ................ *Pentane ........................ 2- Pentanone .................. Perchloroethylene ................ Perchloromethyl mercaptan ........ Perchloryl fluoride ............... * Petroleum Distillates (naphtha) ..... Phenol-Skin ................... p-Phenylene diamine-Skin ...... Phenyl ether (vapor) .............. Phenyl ether-Biphenyl mixture (vapor) Phenylethylene, see Styrene ..... Phenyl glycidyl ether (PGE) ... Phenylhydrazine-Skin ........... Phosdrin (Mevinphos )-Skin.... Phosgene (carbonyl chloride) ...... Phqsphine.................... Phosphoric acid .. Phosphorus (yellow) ... Phosphorus pentachloride .. Phosphorus pentasulfide ... Phosphorus trichloride . Phthalic anhydride .... Picric acid-Skin .... Pival (2-Pivalyl-1, 3-indandione) . Plaster of Paris . Platinum (Soluble Salts) as Pt . Polytetrafluoroethylene decomposition
products .... Propane ...... , f3 Propiolactone . , .... Propargyl alcohol-Skin .. , n-Propyl acetate .. Propyl alcohol .... n-Propyl nitrate .. Propylene dichloride .. , Propylene imine-Skin . Propylene oxide .. Propyne, see Methylacetylene . , Pyrethrum . , . , Pyridine ..... , , , . , Quinone ... RDX-Skin . Rhodium, Metal fume and dusts, as Rh
Soluble salts ... Ronnel . , .. Rotenone (commercial) .. Rouge ............................ . Selenium compounds (as Se) . Selenium hexafluoride ... Silicon carbide ..
0.005
500 200 100
0.1 3 i) A3
5 1 1
10 5 0.1 0.3
0.5 2
E 1
200 200 25
75 2
100
5 0.1
0.05
i) According to analytically determined composition.
Capital letters refer to Appendices.
1970 Addition See Notice of Intended Changes
mg/M3 b)
0.1 0.01 0.5 0.5
D
1,500 700 670 0.8 13.5
19 0.1 7 7
60 22 0.1 0.4 0.4
1 0.1 1 1 3 12 0.1 0.1 D 0.002
A2
A1
840 500 110 350
5 240
5 15
0,4 1. 5 0.1 0,001 10 5 D 0,2 0.4
D
13
FMSI 02928
Sub&Unce
Silver, metal and soluble compounds
Sodium fluoroacetate (1080)-Skin
Sodium hydroxide .....
stibine ... , ....
0.1
starch ...............
* stoddard solvent .. .
200
Strychnine ....
**C Styrene monomer (phenylethylene) .
100
Sucrose ....
Sulfur dioxide ......
5
Sulfur hexafluoride ..... 1,000
Sulfuric acid ..
Sulfur monochloride
1
Sulfur pentafluoride ..
0.025
Sulfuryl fluoride ....
5
Systox, see Demeton .
2, 4, 5 T ......
Tantalum ......
TEDP-Skin .....
Teflon decomposition products .
Tellurium ........................ .
Tellurium hexafluoride ..
0.02
TEPP-Skin ................
C Terphenyls ..................
1
1, 1, 1, 2-Tetrachloro-2, 2-di-
fluoroethane ......
500
1, 1, 2, 2-Tetrachloro-1, 2-di-
fluoroethane .........
500
1, 1, 2, 2-Tetrachloroethane-Skin
5
Tetrachloroethylene, see Per-
chloroethylene ......
Tetrachloromethane, see Carbon
tetrachloride ...........
Tetrachloronaphthalene-Skin ..
Tetraethyl lead (as Pb)-Skin , . ,
Tetrahydrofuran ............. 200
Tetramethyl lead (as Pb)-Skin
Tetramethyl succinonitrile-Skin .
0.5
Tetranitromethane .. , . , , ,
1
Tetryl (2, 4, 6-trinitrophenyl-
methylnitramine)-Skin .
Thallium (soluble compounds)-Skin as Tl
Thiram .........
Tin (inorganic cmpds, except SnH4
and Sn02) .......
Tin (organic cmpds) .....
Tin oxide ............
Titanium dioxide ........
Toluene (toluol) ......... C Toluene-2, 4-diisocyanate ....
200
o. 02
a-Toluidine-Skin .......
5
Toxaphene, see Chlorinated camphene
Tributyl phosphate ............... ..
1, 1, 1-Trichloroethane, see Methyl
chloroform ......
1, 1, 2-Trichloroethane-Skin ...
10
mg/M3b)
0.01 0.05 2 0.5 D 1, 150 0.15 420 D 13 6,000 1 6 0.25 20
10 5 0.2 A2 0.1 0.2 0.05 9
4,170
4,170 35
2 0.100 j) 590 0.150 j) 3 8
1.5 0.1 5
2 0.1
D D
750 0.14 22
5
45
j) For control of general room air, biologic monitoring is essential for personnel control.
1970 Addition
** See Notice of Intended Changes
14
FMSI 02929
Substance
ppma)
Trichloroethylene ........ Trichloromethane, .see Chloroform Trichloronaphthalene-Skin .. 1, 2, 3-Trichloropropane .... 0 1, 1, 2-Trichloro 1, 2, 2-tri-
fluoroethane .. 0 Triethylamine 0 Trifluoromonobromomethane .... * Trimethyl benzene ... 2, 4, 6-Trinitrophenol, see Picric acid 2, 4, 6-Trinitrophenylmethylnitramine,
see Tetryl ..... 0 Trinitrotoluene-Skin . Triorthocresyl phosphate .. Triphenyl phosphate ....... o o o Tungsten & compounds, as W
Soluble . o o o o , Insoluble .... o , Turpentine . o Uranium (natural) sol. & insol. compounds as U .. o C Vanadium (V205 dust) ...... 0
(V205 fume) ........... .. Vinyl benzene, see Styrene ..... 0 **C Vinyl chloride .................... . Vinylcyanide, see Acrylonitrile Vinyl toluene ......
Warfarin ........ o. o Xylene (xylol) ..................... . Xylidine-Skin o o Yttrium . o Zinc chloride fume ......... Zinc oxide fume ..... 0 0 0 Zirconium compounds (as Zr) .
100 50
1,000 25
1, 000 25
100
500 100 100
5
mg/M3 b)
535
5 300
7,600 100
6,100 120
1.5
0.1 3
1 5 560
0.2
o. 5
0.1
1,300
480 0.1
435 25 1 1 5 5
Radioactivity: For permissible concentrations of radioisotopes in air, see U.S. Department of Commerce, National Bureau of Standards, Handbook 69, "Maximum Permissible Body Burden.s and Maximuq1 Permissible Concentration.s of Radionuclides in Air and in Water for Occupational Exposure," June 5, 1959. Also, see U.S. Department of Commerce National Bureau of Standards, Handbook 59, "Permissible Dose from External Sources of Ionizing Radiation," September 24, 1954, and addendum of April 15, 1958.
r
J
* 1970 Addition ** See Notice of Intended Changes
15
FMSI 02930
MINERAL DUSTS
Substance
SILICA
**
Crystalline Quartz, Threshold
Limit
calculated
from the formula ...........
m.p.p.c.f.e)
250 f) %Si02+5
** Cristobalite
Amorphous, including natural diatomaceous earth ......
20
SILICATES (less than 1% crystalline silica)
** Asbestos, all types ..........
Mica ............ Portland Cement o 0 Soapstone .............
Talc (non-asbestiform) .........
Talc (fibrous), use asbestos limit. .... Tremolite, see asbestos ..........
5 20 50 20 20
o... .Graphite (natural) ..........
15
** "Inert" or Nuisance Particulates
50 (or 15 mg/M3
whichever is the
see Appendix D
smaller) of total dust < 1% Si02
Conversion factors mppcf x 35. 3 = million particles per cubic meter =particles per c. c.
e) Millions of particles per cubic foot of air, based on impinger samples counted by light-field technics.
f) The percel}tage of crystalline silica in the formula is the amount determined from airbOrne samples, except in those instances in which other methods have been shown to be applicable.
** See Notice of Intended Changes for Mineral Dusts. 16
FMSI 02931
NOTICE OF INTENDED CHANGES (for 1970)
These substances, with their corresponding values, comprise those for which either a limit has been proposed for the first time, or for which a change in the "Adopted" listing has been proposed. In both cases, the proposed limits should be considered trial limits that will remain inthe listing for a period of at least two years. During this time, the previously Adopted Limit will remain in effect. If, after two years no evidence comes to light that questions the ap~0}1ria1:eness of the values herein, the values will be placed in the 11Adopted" list. Documentation is available for each of these substances.
Substance
ppm
2-Acetylamlnofluorene-Skin ...... + Allyl glycidyl ether ..............
4-Aminodiphenyl-Skin .......... +Ammonia ................ + Ammonium chloride fume .......... .
Asphalt (petroleum) fumes ....... + Butyl lactate ............. + Camphor (synthetic) ............ + Diazinon-Skin ........... + 2-N Dibutylamino ethanol-Skin ....
Dichlorobenzidine-Skin ...... + Diethylene triamine-Skin ..........
4-Dimethylaminoazobenzene ........ . Fibrous glass ............. + C Formaldehyde ............. + Iron pentacarbonyl ..............
+ Mercury (Alkyl compounds) - Skin . + Mercury {all forms except alkyl) .. + Methyl chloride 00 00 00 00
Methyl 2-cyanoacrylate ............. . + Methylcylopentadienyl manganese
tricarbonyl {as Mn) .............
Methyl demeton-Skin ........... Methyl parathion-Skin ...... Phenothiazine-Skin .................
+ Rosin Core Solder, pyrolysis products
5 25
1 2
2 1
g)-2 0.01
100 2 0.1
Styrene .................... 100 +C Subtilisins (Proteolytic enzymes) ....
+Vanadium (V205 Fume) as V ... Vinyl acetate ......................
+ Vinyl chlori:le ..................
+ Wood dust (non allergenic) .......... .
10 200
mg/M3
A1
221 A 18 10 5 5 12
0.1
141 A 4 Al
D 3
0.08 0.01 0.05 210 8
0.2 0. 5 0.2 5 0. 1 (as alde-
hyde) 420
0.0003 (as too%
pure crystalline enzyme)
0.05 30 770
5
+ 1970 Revision or Addition Capital letters refer to Appendices
g) <5-7 JJ. Diameter, No TLV for coarse fibrous glass has yet been set.
17
FMSI 02932
NOTICE OF INTENDED CHANGES (Cont'd) MINERAL DUSTS
SUBSTANCE
+ Asbestos (All types) + Coal dust (bituminous)
Cristobalite + 'Inert' or Nuisance Parti-
culates +Quartz
Silica, fused Tridymite
5 fibers/ml > 5/lin lengthk)
2 mg/m3 (respirable dustjm)
Use one-half the value calculated
from the count or mass formulae
for quartz.
10 mg/M3 or 30 mppcf (whichever
is the smaller) of total dust < 1%
Si02n) TLV in mppcf:
300 %Si02+10
TLV for respirable dust in mg/m3:
10 mg/M3P)
% Respirable quartz + 2 TLV for "total dust", respirable and nonrespirable:
30 mgjM3 %quartz+ 3
Use quartz formulae
Use one-half the value calculated from formulae for quartz.
+ 1970 Revision or Addition
k) As determined by tbe membrane filter method at 430 X magnification phase contrast illumination. Concentrations > 5 fibers/ml, but not to exceed 10, may be permitted for 15-minute periods each hour up to five times daily.
m) "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 Deposition and Rentention of lnhaled Aerosols, p. 149. Academic Press, New York, New York, 1964.
(2) Interim Guide for Respirable Mass Sampling, AlliA Aerosol Technology Committee, AlliA J. ~. 2, 1970, p. 133.
n) This automatically reduces all particulate substances in Adopted list with TLV of 15 mg/M3 to 10 mg/M3.
p) Both concentration and per cent quartz for the application of this limit are to be
determined from the fraction passing a size-selector with the following characteristics:
wAerodynamic Diameter ( (unit density sphere)
<2
2. 5 3. 5 5.0 10
%passing selector
90 75 50 25 0
18
FMSI 02933
APPENDIX A
Al Because of the high incidence of cancer, either in man or in animals, no exposure or contact by any route, respiratory, oral or skin should be permitted for the compounds:
2-Acetylaminofluorene 4-Aminodiphenyl Benzidine & its salts Dichlorobenzidine 4-Dimethylaminoazobenzene
beta-Naphthylamine 4-Nitrodiphenyl N-Nitrosodimethylamine beta-Propiolactone
Because of the extremely high incidence of bladder tumors in workers handling beta-naphthylamine and the potential carcinogenic activity of the other compounds, the State of Pennsylvania prohibits the manufacture, use and other activities that involve human exposure without express approval by the Department of Health.
Polytetrafluoroethylene* dec om position products. Thermal decomposition of the fluorocarbon chain in air leads to the formation of oxidized products containing carbon, fluorine and oxygen. Because these products decompose in part by hydrolysis in alkaline solution, they can be quantitatively determined in air as fluoride to provide an index of exposure. No TLV is recommended pending determination of the toxicity of the products, but air concentrations should be minimal.
Gasoline and/or Petroleum Distillates. The composition of these materials varies greatly and thus a single TLV for all types of these materials is no longer applicable. In general, the aromatic hydrocarbon content will determine what TLV applies. Consequently the content of benzene, other aromatics and additives should be determined to arrive at the appropriate TLV (Elkins, et al. A.I.H.A.J. 24, 99, 1963).
* Trade Names: Algoflon, Fluon, Halon, Teflon, Tetran
APPENDIX I
8.1 THRESHOLD LIMIT VALUES FOR MIXTURES
When two or more hazardous substances are present, their combined effect, rather than that of either individually, should be given primary consideration. In the absence of
19
FMSI 02934
information to the contrary, the effects of the different hazards should be considered as additive. That is, if the sum of the follawing fractions,
cl c2
Cn
-+-+ ------
Tl T2
Tn
exceeds unity, then the threshold limit of the mixture should be considered as being exceeded. C1 indicates the observed atmospheric concentration, and T1 the corresponding threshold limit, (See Example lA.a.).
Exceptions to the above rule may be made when there is good reason to believe that the chief effects of the different harmful substances are not in fact additive, but independent as when purely local effects on different organs of the body are produced by the various components of the mixture. In such cases the threshold limit ordinarily is exceeded only when at least one member of the series(C-+l Or+C2-etc.)
Tl T2 itself has a value exceeding unity, (See Example lA.b.).
Antagonistic action or potentiation may occur with some combinations of atmospheric contaminants. Such cases at present must be determined individually. Potentiating or antagonistic agents are not necessarily harmful by themselves. Potentiating effects of exposure to such agents by routes other than that of inhalation is also possible, e.g. imbibed alcohol and inhaled narcotic (trichloroethylene). Potentiation is characteristically exhibited at high concentrations, less probably at low.
When a given operation or process 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 substance. In such cases, the threshold limit used for this substance should be reduced by a suitable factor, the .magnitude of which will depend on the number, toxicity and relative quantity of the other contaminants ordinarily present.
Examples of processes which are typically associated with two or more harmful atmospheric contaminants are welding, automobile repair, blasting, painting, lacquering, certain foundry operations, diesel exhausts, etc., (Example 2.)
20
FMSI 02935
THRESHOLD LIMIT VALUES FOR MIXTURES EXAMPLES
1A. General case, where air is analyzed for each component
a. Additive effects. (note: It is essential that the atmosphere be analyzed both qualitatively and quantitatively for each component present, in order to evaluate compliance or noncompliance with this calculated TLV.)
C1 T1
+ 'Cf22 +
C3 T3
+
. ' ' '
=1
Example No. 1:
Air contains 5 ppm of carbon tetrachloride (TLV = 10 ppm) 20 ppm of ethylene dichloride (TLV = 50 ppm) and 10 ppm of ethylene dibromide (TLV = 25 ppm)
Atmospheric concentration of mixture
5 + 20 + 10 = 35 ppm of mixture
~ 20 ~ = 25 + 20 + 20 = 1 3
10 +50+ 25
50
Threshold Limit is exceeded, Furthermore, the TLV of this mixture may be calculated by reducing the total fraction to 1.0; i.e.
TLV of mixture = 1:~ = 27 ppm
Example No. 2:
Air contains 200 ppm of hexane (TLV = 500 ppm) 100 ppm of methylene chloride (TLV = 500 ppm) and 20 ppm of perchlorethylene (TLV = 100 ppm)
Atmospheric concentration of mixture
200 + 100 + 20 = 320 ppm of mixture
200 100 20 200 + 100 + 100
500 + 500 + 100 =
500
400 500
=
0
8
Threshold Limit is not exceeded. The TLV
of this mixture
320 = 0.8
=
400
ppm
21
FMSl 02936
lB. 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 material; e.g. on a time weighted average exposure basis, all of the liquid (solvent) mixture eventually evaporates.
a. Additive effects (approximate solution)
1. The percent composition (by weight) of the liquid mixture is known, the TLVs of the constituents must be listed in mg/M3.
(NOTE:
In order to evaluate compliance with this TLV, field sampling instruments should be calibrated, in the laboratory, for response to this specific quantitative and qualitative air-vapor mixture, and also to fractional concentrations of this mixture; e.g., 1/2 the TLV; 1/10 the TLV; 2 X the TLV; 10 X the TLV; etc.)
TLV of mixture =-:----------:---'1'----::------------::-
fa fb
fc
fn
TLVa + TLVb + TLVc +..... TLVn
Example No. 1:
Liquid solvent contains (by weight) 50%
heptane (TLV =2000 mg/M3) 30%methylene
chloride (TLV = 1740 mg/M3) 20% per-
chlorethylene (TLV =670 mg/M3)
TLV of mixture =
11 ~0.--.75----ro'."3'0".-n2 - . 00025+. 00017+. 0003
2000+1740+670
1 . 00072
1390 mg/M3
Of this mixture: 50% or 695 mg/M3 is heptane, 30% or 417 mg/M3 is methylene chloride and 20% or 278 mg/M3 is perchlorethylene
These values can be converted to ppm as follows:
heptane:
2000 mg/M3 = 500 ppm
1 mg/M3 = 0. 25 ppm
695 mgjM3 = 174 ppm
methylene chloride: 1740 mg/M3 = 500 ppm
1 mg/M3 = 0. 287 ppm 417 mg/M3 = 119 ppm
22
FMSI 02937
perchlorethylene: 670 mg/M3 = 100 ppm 1 mg/M3 = 0. 15 ppm
278 mg/M3 = 42 ppm
The TLV of this mixture = 174 + 119 + 42 = 335 ppm.
1B,b. General Exact Solution for Mixtures of N Components With Additive Effects and Different Vapor Pressures,
(1)
C1 T1
C2 + T2
+. '"
+
Cn Tn
= 1;
(2) C1 + C2 + + Cn = T;
+ TCn = 1.
By the Law of Partial Pressures,
and by Raoult' s Law,
(4)
0
P1 = F 1P1
Combine (3) and (4) to obtain
.(5) C1 = aF1p1
Combining (1), (2, 1) and (5), we obtain
and solving for T, (6.1)
or
(6. 2)
i =1
T= i = n
~
i =1
23
FMSI 02938
T = Threshold Limit Value in ppm.
C = Vapor concentration in ppm.
p = Vapor pressure of component in solution.
pO = Vapor pressure of pure component.
F = Mol fraction of component in solution. a =A constant of proportionality.
Subscripts 1, 2, n relate the above quantities to components 1, 2, . n, respectively.
Subscript i refers to an arbitrary component from 1 ton.
Absence of subscript relates the quantity to the mixture.
lB. c. Solution to be applied when there is a reservoir of the solvent mixture whose composition does not change appreciably by evaporation.
Exact Arithmetic Solution of Specific Mixture
Mol, Density TLV pOat wt, 250C
Mol fraction in half-andhalf solution by volume
Trichloroethylene (1) 131.4 1.46g/ml 100 73mmHg
0.527
Methylchloroform (2) 133.42 1.33g/ml 350 125mmHg
(0. 527) (73) 38.2
0.473
(0. 473) (125) 59.2
TLV = 38. 2 + 59. 2
38.2 59.2 100 + 350
(97. 4) (350) 133.8 + 59.2
(97.4) (350) 177 193.0
TLV = 177 ppm
(Note difference in TLV when account is taken of vapor pressure and mol fraction in comparison with above sample where such account is not taken.)
2. A mixture of one part of (1) parathion (TLV, 0.1) and two parts of (2) EPN (TLV, 0.5).
24
FMS' 02939
Cm = 3C1 C1 2C1 3C1
0.1 + o. 5 = Tm
o7=C1s--_
3C1 Tm
Tm = ~ 5 = 0.21 mgjM3
1C. TLV for Mixtures of Mineral Dusts.
For mixtures of biologically active mineral dusts the general formula for mixtures may be used,
For a mixture containing 80% talc and 20% quartz, the TLV for 100% of the mixture is given by:
TLV 1 8.4 mppcf 0.8 0.2
20 + 2.5
Essentially the same result will be obtained if the limit
of the more (most) toxic component is used provided the effects are additive. In the above example the limit for 20% quartz is 10 mppcf.
For another mixture of 25% quartz, 25% amorphous silica and 50% talc:
TLV
1
0,25
"'2.""5
+
-0--.2w5-
+
0.5 20
7.3 mppcf
The limit for 25% quartz approximates 8 mppcf,
25
FMSI 02940
APPENDIX C
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 below the TLV.
These limiting excursions are to be considered to provide a 'rule-of-thumb' guidance for listed substances generally, and may not provide the most appropriate excursion for a particular substance. Efforts are being made to develop such specific excursions, when indicated to be significantly different from that recommended by the present excursion factors.
Substance
TLV
Excursion Factor
Max. Cone. Permitted for short
time
Nitrobenzene Carbon tetrachloride Carbon monoxide Acetone Boron trifluoride Butylamine Styrene monomer
1 ppm 10 ppm 50 ppm 1000 ppm C 1 ppm C 5 ppm C 100 ppm
3 2 1.5 1.25
3 ppm 20ppm 75 ppm 1250 ppm
1 ppm 5 ppm 100 ppm
For all substances:
TLV = 0- 1 (ppm or mg/m3), Excursion Factor
TLV = 1- 10
"
""
TLV = 10- 100
"
TLV = 100 - 1000 "
=3 =2
1.5 = 1.25
BASIS FOR ASSIGNING LIMITING "C" VALUES
By definition in the Preface, a listed value bearing a "C" designation refers to a 'ceiling' value that should not be exceeded; all values should fluctuate below the listed value. This, in effect, makes the "C" designation a maximal allowable concentration (MAC). In general, the bases for assign-
26
!'
,j
FMSI 02941
ing or not assigning a "C" value rest on whether excursions of concentration above a proposed limit for periods up to 15 minutes may result in a) intolerable irritation, b) chronic, or irreversible tissue change, or c) narcosis of sufficient degree to increase accident proneness, impair self-rescue or materially reduce work efficiency.
APPENDIX D
Some "Inert'' or Nuisance Particulates q)
Alundum (Al203) Calcium carbonate Cellulose (paper fiber) Portland Cement
Corundum (Al203) Emery Glycerine Mist Graphite (synthetic) Gypsum Vegetable oil mists
(except castor, cashew nut, or similar irritant oils)
Kaolin Limestone Magnesite Marble Pentaerythritol Plaster of Paris Rouge Silicon Carbide Starch
Sucrose Tin Oxide Titanium Dioxide
q) When toxic impurities are not present, e. g. quartz< 1%.
APPENDIX E
Some Simple Asphyxiants - "Inert" Gases and Vapors
Acetylene Argon Ethane Ethylene Helium
Hydrogen Methane Neon Nitrogen Nitrous Oxide Propane
1970 TLV COMMITTEE MEMBERS
Paul E. Caplan Hervey B. Elkins, Ph. D. W. G. Fredrick, Sc. D. Bernard Grabois, P. E. Paul Gross, M. D. Wayland J. Hayes, Jr., M. D. John W. Knauber
Harold N. MacFarland, Ph. D. Frederick T. McDermott E. Mastromatteo, M.D. Col. WalterW. Melvin, Jr., M.D. Ralph G. Smith, Ph. D. Mitchell R. Zavon, M. D.
Herbert E. Stokinger, Ph. D., Chairman William D. Wagner, Recording Sec'y
27
FMSI 02942
.. Brake Lining Decomposition Products
Jeremiah R. Lynch* ABSTRACT
A number of investigators have found asbestos bodies in the.lungs of urban residents who were not occupationally exposed to asbest,os. A relationship between the ca~cinogenic properties of asbestos and the urban excess of lung cnncer has been ~uggested. The decomposition products of br~~e linings have been described as a possible source of these fibers. Brake testing laboratory m~thods were used to test fiber emission from a variety of friction products. Only a ver1 E3all fraction of the asbestos escaped as free fiber while the remainder was transformed into some other, non-fibr'ous, !1'.ineral. A significant release of free fiber occurred only under conditions extreme enough to produce brake failure.
*U. S. Public Health Service - Depart;nent of Health, Education and Welfa:ce Burea of Disease Prevent~on and Environmental Control National Center for Urban and Industrial Health Occupational Health Progra8 1014 Broadway, Cincinnati, Ohio 45202
{) , \
y\
l \J. I
FMSI 02943
-''
Brake Lining Deco~position Products
Jeremiah R. Lynch*
Introduction The occurrence of coated fibers referred to as "asbestos bodies" in
the lungs of urban poptuations not occupetionally exposed to asbestos has been noted by several investigators . The results of several autopsy
series, as s~~arized by Cooper,(l) are shown in Table l.(l-6) Thampson,(7)
in suggentins possible modes of_ exposure that could account for these bodies, stated "The avere{';e private motor vehicle vears out three or four Eeta of br&ke linings end ~ne or tvo clutch linings in its lifetime, and CCor%)1ercir.]. .r..nd public tre..nsport vehicle: a vear out mEUly more. These linings consist largely of e.sbestos whic:h is ground to dust as the linings vear, and most \lear occur~ in bullt--up a.:r~~!l. This alone in most cities vould involve th~ dischsr.se of YLeny tons of asbestos dust and fib.~rs in
the streets' each year". Since asbestos has been implicated a~ a carcino-
gen(8) and lung cru1cer haa a higher ir.cidence(9) among urben populations, the fe.te of the asbestos wort fro~ brake liniP...gs becomes signi fica.'1t.
*U. S. Public Health Service - Depart~ent of Health, Educa~ion and Welfare
Bureau of Dises.se Prev~ntion &'1d Envirorr::~enta.l Control National Center for Urban and Industrisl Health Occupational Hee.l th Progre.3
1014 Broadwey, Cincinnati, Ohio 45202
FMSI 02944
Locstion Cepe To:.m (2) Miami (2) Pittsburgh ( 3)
J ohe.nneoburg (4) Finls.nd ( 5)
Hontrea.l ( 6) San Francisco ( 1)
-2Table 1
Year
.1963 1965 1965 1965 1966 1966 1966
%Po3itive
26
27
41 39
58
48
42
..
.'
,
FMSI 02945
-3-
"'
Brake Lining Comuosition The average co~poaition of typical brake linings of the type
tested is shoVil in T~ble 2. Incrividual mixes may varJ considerably from these averages.
Table 2
Ingredient Asbestos Resins and Pol~ers Oxides rilld pig~enta Hetals Carbon, Graphite, etc.
Automobile 55
28
9 3
_L
100%
~ruck
33
48 16
2 1 100%
Each of these ingredients pcrfol"l:\s a particular flil:.ction. The
asbestos provides strength, he&t resistance and selectiYe deco::position
under stress. The resins and pol:,.'";'.lers hold the other ino'cdients to.sether.
Variou.s o:;::ic1eG sre c.O.ded a.s plg;r.cnts E'-.rld. to in:,?:rove the grip of the 1 inin3
on the ch\..'.Ic!. Soft m<!tals f:uch s.s lze.cl e::C. brsst~ improYe 1-;ear while ca.Tbon
e.nd gr~_:::,hite serve aE friction modifiers.
Brake lining quality depends to a large extent on the type of bind:=r used. Linseed oil, v~ich begins to ceCOX?OS2 at about 450F, i~ used for
.light service bra..'-<.es. Hore de.::: 9Jid.in.:.; se~:vic c requires br&ke3 made fro~s
cs.shev typ-e resins or oil t:odified ph~nolic r~sins. Thes~ ingr2die:1ts are
~
I:J.ixed, either drJ or vi th a solvent added, :forc>.ed into sha:pe and cured
FMSI 02946
-4-
in ~~ oven. The hardened lining is then cut, ground and s~~ded to the
"'precise dimensions of the finished linings. The dust produced by the
abreding oper~tions in asbestos friction product factories (Figure 1) contains free.~sbestos fibers that are similar to th0ee in industries where cancer is k~ovn to be in excess(lO). The question to be resolved, therefore, is whether the dust produced by the normal wear of br~e linings contains this same type of free asbestos fiber.
Test Methods In an initial exploratory survey, the dust obtained from inside
autczobile braLe drums re~ved fer brake relining was ext~ined by electron microgr~ph. FiGure 2, which is typice~ of the series, does not reveal any free fibers. Hol?ever, thic finding did r.ot eliminate the possibility that fre.e r,sbes tos fibers ver<e released ~nd thOJ.t they bad ecapcd into
'
the at~osphcre. 'l'o exr.:nine this hypothesis ~ series of experi.nents \ras devised to peiT.J.it sretpling decc-w.Il'Osition products of the lining und.er simulated operating conditions. The tests (Table 3) vere performed vith.the brake testing ~~chines in the laboratory of e ~~jor br~~e lining mcnuf~cturer. Most of the tests vere pcrfor.::ed on e.. friction-testing ne.:::hine ,;bich used one--in~h-squa.:Le sB..:'.ples of the test lining. He<l.ting end coDling
.
ap:ps..::-atu::~ p~mi tteo. control of c."t:n.:-'!1 tenp-er?.ttll'e fro::~ those encountered with inten1ittent brake use to the tla.xinu:u te.Jlpere.ture w'!1ich occurred only in extre"-lely rapid or "pmlic'; stops fro:.:: high speed. Other tests were perfol-J.!led en a bre..i-;.e-testir...g dyn;:,;:.o::.>Jr::ter vhich subjected a cu.:;:ph:te
FMSI 02947
.
-5-
brake
assembly
to
a
series
of
stops
and
starts
fr~
different
"
speeds
and
at different deceleration rates to s~ulate actual driving conditions.
In these tests the dn..'"::l ter:1peratures varied according to the driving
condition sL~ulated. During each nL~ at a test condition, a sample
vas collected on en 0.8 ~ pore size ~embr~~e filter. Electron micro-
graphs of these filters were exa.>:dned to determine the presence of free
asbestos fibeTs e.nd to qus.ntify these fibers v~1en more than a few occurred.
- : - - - - - - - - - - - - - -----~-~------:-::;--
FMSI 02948
-6-
.. Table 3
Test Results by Electron Hicro3ra;ph
Product
Test Brand Method
No. of Conditions Preser,ce of %Free
~les of Test-F Free Fibers Fibern
l. Automobile drum brakes
A
Friction
6 300-800 Fe'W'
<l
2. II 3. II 4. II
B Friction
c Friction c Ftict:i.on
6 250-800 None
0
5 300-700 Fe'W'
4::1
l
700-900
Numerous .....10
5. "
D Fr.iction French
5 300-800 Fe'W'
<l
6. "
7. II
E Friction
F Friction German
5 300-700 Fe;r 5 300-800 Fe'W'
<l
<.1
8. II
9. II
10. II
G Friction G Friction H Friction
2 100-.500 Few
.c:::l
1 600-700 numerous .....15
2 100-600 Few
<1
11. Autoi:!lobile clutch
J
Dyn&Uometer
l
normal driving
None
0
12. Auto~obil~ disk brake
K
Dyna.illOJaeter
l
no:n!!al drivi;.g
Fe'W'
.(5
13. Bus drum bra..'l(e
1 DynS!:lo:neter 1 city
None
driving
0
14.
15. Truck dr\.':il bre.>.e {light)
M F
Friction Friction
2 450-550 10 . 300-800
None Few
0 <1
t!Weight estio~te~ fr~~ fiber vol~~e.
..
FMSl 02949
-1-
Results
.
The object of the tests was to determine vhat proportion of the
asbestos kno~ to be present in the lining appeared as free fiber in the
decomposition product. No attempt vas made at a mass balance between the
material worn from the lining and the deco~position product since it vas
not possible to collect all of the deconposition product. Hovever, the
percentazes obtained in the fraction of decomposition product examined
are applicable to the total material worn from the brake and may be
compared to the percentage of asbestos originally present.
.In all but a few tests the automo~ile druB br~~e linings shoved .
less thP...'1 1% free fiber in the decomposition product as ccrapared to [lbout
.
50% in the lining. An electron micrograph of the decomposition product
obtained frci.'l a typics.l test in this grou:p is shO'Im in Figure 3. In those
\
tests vhere a significr..nt m2.ss of free fiber vs.s release'd (Figure' 4), the
temperature 'vas in an extremely high rmge for the lining in question as
evidenced by repid drop in the coefficient of friction. Had these linings
been subjected to like conditions in a vehicle, the br~~es would have failed.
Sii::ilar results were obtained in the bus e..:1d b-uck drum brake tests
and in the clutch test. The experimental model disk br~~e tested did release some ( > 5%) free fibers, but no conclusion can be dra~m. from a slngle
Sru;J.ple.
FMSI 02950
DISCUSSION Except in all but the most extreme driving conditions, only a very small
..fraction of the 30 to 50% asbestos present in a brake lining escapes into the
atmosphere as free fiber. The question remains: What happened to the asbesto ~ prevalent theory of brake operation holds that wear occurs not by abrasion of the lining by the drum but by the production of minute areas of intense heat at the points of contact between the drum and the lining. Decomposition, not only of the binder but of the asbestos as well, occurs at these locations since the breakdown temperature of asbestos, about 900F, is exceeded. The
/
decomposition products will thus include not free asbestos fibers, but a different mineral resulting fr~m the ~mal metamorphosis of the asbestos.
Some independent experiments done at a brake lining research laboratory(ll)hav shown that all of the magnesium present in the chysotile asbestos originally i .:.he lining can be accounted for in the decomposition products. However, the characteristic X-ray diffraction pattern of chrysotile asbestos had vanished. Thus, it is apparent that under conditions in which asbestos is worn from the lining of a brake, the asbestos is destroyed.
CONCLUSION Onlj a very small proportion of the asbestos worn from brake linings is releas as free fiber; the remainder 1s converted into some other mineral as a result of the extreme temperatures generated at small spots on the linin-g surface. Thus, although urban air contains a few free fibers as a result of brake lining wear, they represent a very small proportion of the total asbestos usee .;n the manufacture of brakes. Many sources of respirable fibers not associate
. . (12) with asbestos proc1'.'':"":-s have been iden"tified and the free fibers from brake lining wear appear to be an inconsequential health factor in urban air pollution.
FMSI 02951
-9-
References
1. Cooper, W. C.: Asbestos as a Hazard to Health. Arch. of Env. Health. 15:285 (1967).
2. Thomson, J. G., R. 0. C. Kaschula and R. R. McDonald: Asbestosis as a 1-fodern Urban Haza!"d. S. Afr. Mod. J. 37:77 (1963).
3. Catma, D., R. S. Totten_and P. Gross: Asbestos Bodies in Human Lungs at Autopsy. JAK~ 192:3] (1965).
4. Webster, I., in discussion of Tho~son, S. F.: Physiological Effects of D2o in Hn...-cma.ls, An."l. N. Y. Ace.d. Sci. 84:736 (1960).
5. l1eu.n:nan, L.: Asbestos, Bodies imd Pleural Ple.ques in a Finish series of Autopsy CHses, Acta Path Hicrobiol Scr-..nd Suppl 181:107 ( 1966).
'
6. Aryilrol, L. end H. Thurlbeck: The Incidence of Asbestos Bodies in the
Lungs of R~:mdon Autopsies :ln Montreal, Canada. Med. Assoc. J. 95~ 1179 (1966). 1. Thomson, J. G.: A~bestos and the Urb8.11 Dweller. Ann. N.Y. Acad. Sci. 132:196 (1965). 8. Selikoff, I. J. , J. Churg and E. C. He..r:Elond: Asbestos Exposure and Neoplasia J/.J!A 188:22 (1964). 9. Buell, P. and J. E. Durn: Rela.tive Impact of Smoldng and Air Pollution on Lung Cancer. . Arch. of Env. Health 15: 291 (1967) . 10. Enterline, P. E. and H. A. Kendrick: Asbestos Dust E.xposm-es at Verious Lev-els and Hortdity. Arch. Env. Health 15:181 (1967~. 11. Sinclnir, D.: Study of Wear Dust fra:t Brake Lining. Johns-Eanville Research and En.:;inee:dng Center, P~rson-"..1 co:r:I"llomication ( 1967). 12. Cr~ley, L. J., R. G. Keenan, G. W. EdvnrJs and J. R. LJ~ch: Sources and Identification of Respirable Fibers. Preseuted at ~. Inaust. Hyg. Conf., Chi~e3o, Illinois ~1967).
FMSI 02952
___ __ _,____. ..,___,_;..
_ . . __.....
.""
I
- '' . '~ :
.. . - '.~-. ,,
....
., ,;.~-..,~---:.-~~
.---~'
.\.:..".'.-, i..r}' \, ~::.~~8':2_:_~ ~..;..:..-
.
.
.
.
.
.
.
.
.
.
'
;.
._._.~~-
,.
.' .
... : ..
~.
.,
...- _, ,_.
,I ..
;
.. ...'. . "' ::~ ":'
' ' .,._
,.
.;
~ '.. ':- -~. ~-:. ~-:
.'... -...
"
'
:
.. "'. "\,:._
... . ''_:/. -~~ .. ~ . .. , .
.- t ..,-;
-. ).J'
~
I
''
I; ;
. ...:~. ~-;.~ -'~\ ;"
""-
~-
'.
Figure 1. Bru.k':! lining fa::tor:r d'-'St.
..... '
' 'v .
... . !
~-
...
.....
,I
'
FMSI 02953
-
0
(
e 0t
'(; 0
Figure 2. Dust re..~oved frcr:1 pra.~e drum.
FMSI 02954
.F I
..- . ' '
,...
0 ..., 'l(;\
. ~ .- . .
-~~t~
.
-'
: ;:
..
. f'~!(' l~ \i:..;:J)~
. ....... ...- ,, -:
(_;dJ;..J ~
.~-- ., ; . _-_
.
,
I (
I
I.
..II.
..
._--~-~; ~ ~:~ .
. ~ .'.
.,:;~
. :~
_,
,.,;{ ,,
. :4
.....-h:f1i!.' .
) ."'.-':'-*
.,
.r,:-.
, ...J,\;.'
t< uJ
. ..... -_;__
...'!--"'.
-'-,. :.1~-~.
__ __ ' r ' .':
.... ~ -~
. .-,-:: ~ :
....... 'T 1,~
.. -.-_.-~ -~ l . .
. ,r
..
.. -~
... . <.1 P.'! ~ .. '
..... '
. .-
-.;_
. - -~
.l.
..
Fig1ir(! 3. Decc;!lposltion pro.-].nct fro:J. non:a.l vear of bra..~e lin:~r..g.
.------~--------~~~~~~~-'7"~~~"-:~r~~~--~'n"~"':-:~T~~~~-~:.~~~-~~-~~---~e'~~~--.,_~-
"' - ~-. . - - . ..
...
'.c.,
FMSI 02955
....
.l
.
.10
~-
...'\ '
!
.....
-.
'
.
~
;
..(. '-'.: ., :.- ~ ..) I v,~
i
Figure 4. Dccccpositio~ product frc~
brake lini~s n~.. f 3 i1-'~.,.e
---"---z~--------
FMSf 02956
,,
~
w.DR. ~~ tViC Hoi-Suh' Ti:::sn,rr~ol-4/'
.IPCB HEARJNG
CHICAGO, OC/, 15~ /97/
1
Thank you very much for the opportunity to appear in support of your regulations controlling the use and productj_on of asbestos materials and spray insulation.
For purposes of identification, my name is William J, Nicholson. I am Assistant Professor of Community Medicine at the Mount Sinai School of Medicine of the City University of New York. As a physicist, I ,have 'served as coordinator of several projects undertaken by the Environmental Sciences Laboratory of Mount Sinai to evalu~te the ef-, fects of asbes~os exposure, These include an industrial hygiene,research program designed to identify and control asbestos hazards in the insulation industry, the development,of analytical techniques for the quantitation of asbestos in ambient air, and a study of asbestos air pollution in New York City and throughout the United States. Additionall~, I am engaged in several epidemiological studies of disease associated with occupation or environmental exposures to various substance~. ~vo of these studies invoive the effects of asbestos on defined populations.
The justification is strong for controlling the use of asbestos on basis of- the health effects produced by its use, in the past'; The evidence that heavy occupational exposure to asbestos is assoctlted with pulmonary disease dates from 1900 when massive fibrosis was found at post mortem in the lungs of a man who was the last surviyor of a group of 10 men who worked since 1886 in the cardirtg room of an asbestos textile mill, Cases of asbestos-induced scarring of the lungs, asbestosis, were seen with increasing frequency in subsequent years as the use of asbestos increased, However, a hint of addi tionol disease rislc from occupa tiona 1 asbestos exposure was seen in 1935, 'I\vo cases of lung cancer were found in individuals having asbestosis, This portent W8S grimly vC>rified in
FMSI 02957
later studies. In 1947, the Chief Inspocto1 of Factories in Brito in
found lung cancer in 13 per ce'nt of deaths in which asbestosis was
present. To bring us .. UP to date, 70 years after the first lmowledge of as-
bestos disease, and to-'complete the picture of occupational risk from
exposure to asbestos, let me present some data obtained by Dr. Irving J.
.Selikoff, Director of the Environmental Sciences Laboratory, Mount Sinai
School of Medicine. He has followed since January 1, 1943 the 632
members of the New York and New Jersey Lo'cals of the as):>es.tos workers
union, the International Association of Heat and Frost Insulators and
Asbestos Workers. These men apply the insulation to high temperature
pipes and boile:rs in apartment, office building and individ.ual plants.
Sonte of the
u::::c (!0~t?.i~s "' S!!HlJl omcnmt of asbestos -- 7
to 15 per cent, usually, Often it contains none, I-n compa-rison to the
factory exposures during early decades of this century, their exposures
are relatively light. l~nowing their ages in 1943 and using standard tables, it was pass-
ible to calculate the expected mortality experience of th.ese 632 workers. ... This was done by Dr. E. Cuyler Hanunond, C)1ief Epidemiologist of the American Cancer Society, and the results, along with 'those actually seen,
are given in Table I for the years 1943 through 1962,
From all causes, 203 deaths were expected of those who had worked
20 yeats.
In fact, ther~ were 255,
More than 50 mEm who died sho"uld ,
'
not have died. Lookingat the table;-we can see the causes of these
~xcess~death'':
45
died
of
canc. er
of
~ho
iung,
trachea
.
and
pleura
where
FMSI 02958
~
should have died; three times as many died of cancer of the G. I. tract as were expected.
Results of continued observation of the group through June 30 1 1971
are shown in Tables II and n:t.. They represent a catas-trophe. Over half
I
of the deaths were from some form of cancer or asbestosis. Nearly 40% .could be termed "occupational" deaths.
Iri these latter data, special reference should be made to the high death rate from mesothelioma. Twenty-seven cases of this, as yet, incurable disease wore soon. A diffuse canCOJ: of tho lining of tho chest or abdomen, it is so rare that it has yet to be separately classified in the International Classification of Causes of Death. Its occurrence in the general population may be so infrequent as to cause only one death in 10,000. Here, it was the cause of death in one of every ).6 individuols. Moreover, in other studies, its appearance in-increased ~:~mount:; has always been associated with asbestos exposure.
Two other aspects of the research by Doctor Selikoff are important. The first is the evidence of the long lapsed period between onset of asbestos exposure and the incidence bf disease. Lung cancer usually appearsbetween 20 and ~0 years after first exposure to asbestos, and mesothelioma most often after a 35-year lapsed period,
The second aspect is the strong synergism found between asbestos exposure and cigarette smoking in the incidence of lung -cancer. By personal interview in 1962 1 the smoking habi~s of 370 of the 632 men were established, By followi~g the mortality experience of these 370 men, a\ special risk of cigarette smoking was established. From January 1, t963 thrl>ugh February 1 1 1971, in_ 283 -men with a history of cigarette smoking, 40 lung cancers were observed. This is nearly ten times the number ex-
FMSI 02959
4
pectcd in an equivalent cigarette smoking population. In 87 non-smokers, only one lung cancer was seen. Thus, it is not asbestos alone, or cigarette smoking alone, but the combination of the two that produced these grim data. In fact, it is calculated that asbestos workers who
I
smoke run more thi:m 90 times the risk of dying of lung cancer than men who neither smoke cigarettes nor work with asbestos.
These data I have presented to you were from occupational exposures to asbestos. At most, 200,000 men and women in the United States have
such exposures. Hopefully, 70 years after the first ::wareness of asbestos:
disease, working condi ti,ons will be improved to r~duce their risk of disease. But were this the only risk of asbestos exposure, it would not be germane to the regulations under consideration here. Unfortunately, in recent years the evidence has accumulated that the proble;m of asbestos disease has disseminated from the occupational area into the general environment.
Evidence is accumulating that mesothelioma is rapidly increasing among men who worked in tho vicinity of asbestos application. Recall. that mesothelioma is virtually nonexistent in people who have had no exposure to asbestos. In Holland, 22 cases were found during a 6-year period in workers of the de Shelde shipyard. These cases occurred, however, not in asbestos workers, but in members of other trades, welders~ carpenters, ~r painters, all of whom 6nly wonked in an ~rea where asbestos insulation was applied or removed. Similar data have appeared from Great Britain. Here, 80 cases of mesothelioma were found in a survey of the material in the pathology departments of Scottish hospitals i and medical schools from the year!]_l950 through 1967~ An investigation of the occupational background of these cases revealed a strong association
FMSI 02960
5
with shipbuilding.or marine work. Here again, however, the cases were
not often found in insulators but in other trades working near the '
application or removal of asbestos, A further disconcerting feature of the Scottish data is the rapid rise in the rate of occurrence of mesothelioma; 51 of the 80 cases were seen in the years 1964-67, ap-
..
proximately 30 years after the extensive shipbuilding undertaken during
World War II.
The spectrum of disease associated with asbestos now extends even
to environme_rital exposures. In 1960, Wagner, Sleggs and Marchand described 47 cases ~f mesothelioma found during a four-ye'ar period in the
northern Cape province of South Africa, .an area with extensive crocido-
lite asbestos mines. None were seen in the neighboring Transvaal Province
or in 10,000 autopsy cases of workers who had died with known exposures
to silica, Of the 47 cases, approximately half were found to have had
either industrial or mining exposures to asbestos, Virtually all of the
remain.ing cases were in individuals who simply lived or worked in the !.
vicinity of the asbestos mines or mills.
Confirmation of the possibility of environmental asbestos-associated
diseasesoon appeared, Newhouse and Thompson reviewed all mesothelioma
cases at the London Hospital, They corroborated the close association
with asbestos, 31 of the 76 cases having had documented occupational exposure. Of the remainder, 11 had lived, d~cades before, within one-half
mile of an asbestos factory. A similar distr.ibution of cases was found by Lieben and Pistawka in Pennsylvania, One insidious form of indirect
asbestos exposure is that of families of asbestos workers. In the previously mentioned studies, 9 o~ the _!..ondonmesotheliomas were :Ln family
members, as were 3 of t.he 46 Pennsylvania cases,
FMSI 02961
Unfortunately_, these data on the incidence of mesothelioma from
environmental or indirect occupational exposure to asbestos are severely
limited. TI1e exposures in question took place beginning 20 1 30 1 40 or
more years ago. No knowledge exists of the associated asbestos dust
I
exposure levels. Thus, we have no dose-response information on low-
..
level asbestos exposure. We only have knowledge.of a potential risk of
cancer, at exposures much below occupational ones. Obvi~usly, additional
research ~nd continued surveillance arc highly desirable.
r..et'us now turn to specific items in your regulatlons. Firstly, the
t
general requirements of _Section 2 are excellent, particularly with regard
to responsibility and education. We find a great problem to be the ignorance of a potential hazard among marginal users of asbestos. Such
ignorance can easily result in lax procedures. Secondly, the banning of asbestos in spray insulwtiou i:;; ~::uti.L't:ly
appropriate. In New York City we have found this to be a major contrib~-
tor to ambient air asbestos levels. For the past 10 years,.during which
spray fireproofing came to be extensively used, it was not uncommon to
see extensive snowfalls of asbestos-containing material ?Ver widespread
areas of. New York and other metropolitan centers. In some cases, the fireproofing was even done with no attempt to enclose the spray area by
tnrpnulins or othor moons. 'l'o vorify that such fireproofing oporot~ons wore o significant
source of respirable asbestos fiber, air sampl~ng: was conducted in lower Manhattan about construction sit~ whem extensive spraying of asbestos-
containing fireproofing was taking place. This work was done by our Laboratory in conjunction wi ~h th~__Department of Air Resources of New York
City. The results demonstrated thnt spray fireproofing con indeed con-
FMS\ 02962
tribute signifi~antiry to asbestos air poll.ution.
Up to l mile away 1 levels exceeding 0,1 microg.rams per cubic meter
were observed, which exceeds by 100 times background levels found in urban
areas distant from construction sites. While 0,1 micrograms may appear
I
to be a small amount, it could represent more than 10 million minute
..
fibers of asbestos. Moreover, the large clumps of asbestos-containing
material covering the sidewalk serve as a continuing source to be dispersed
by passersby.
As I mentioned earlier, lacking a dose"-response relationship, we
cannot state that env~ronmental exposure levels from this practice are
certain to produce disease, However, it is hard to imagine factory
emissions, even 40 years ago, being more excessive, Since the extensive
spraying of asbestos-containing fireproofing material has only existed
in the construction industry for the last J.u years, riisease cau::;eu uy
the exposure resulting from this practice is 10 or 20 years away. How-
ever, continuing the uncontrolled spraying practices of the past decade
in the face of the mounting evidence of risk to all metropolitan residents
would be playing asbestos roulette with the lives of millions of people,
This method of fire protection for high rise buildings presents an
additional, continuing risk to the occupants of those buildings. Often, the space between the false room ceiling an~ the under side of the fl6o~
above, whfch lias been sprayed with asbestos,,serves as o return plenum
for the air supply system. After filtration, inadequate to remove most as-
bestos fibers that may have eroded into the air stream, this return air is
recirculated throughout the building. The magnitude of this problem has yet to be defined. Until rece~tly_ in New York City., we have not been
allowed to analyze the air in buildings that has been in direct cont~ct
FMSI 02963
..
with risbes tos-con :f:ain:j_ng insulation.
Finally, this spray procedure leaves a legacy of potential risk to
future generations. The lifetime of modern office buildings is short
and the procedures for -the safe future demolition of buildings that could
I
contain more than 100 tons of asbestos as fireproofing have yet to be
devlopcd. Perhaps these procedures will be_found and perhaps they will
be followed but we have no such assurance at this time.
Unfortunatclyg safe procedures developed for the spray application
.I.
of asbesto's-containing materials have not been followed either voluntarily
or under control regulations by contractors. Because of this failure
and because alternative procedures or materials are available, action
..
.
banning this use of asbestos is indeed appropriate.
Moreover, because of uncertain knowledge of the health effects of ex-
posure to mineral fibers other than Hti~~HLus, l t is enti~cly opprcpri~te
that strict control be exercised over other spraying of such substitute
materials. While some forms of "mineral \Vool" and other mineral fibers
have been in UP9 since the 1930s there are still no definitive studies on exposed populations that would, at this time, provid~ assurance that
respirable mineral fibers, other than asbestos, are biologically inert in
humans. In the absence of such assurace, caution is warranted and I
support, in its entirety, Section 3 of your regulations.
On the other items, in Section 4, you m:j.ght wish to add a qualifying
statement that when there is potential release of asbestos to the air,
a special enclosure shall. be used. Many asbestos products used in con-
structinn can be installed with no release of fiber. Asbestos-vinyl. floor
tile is one example. In fa?t, ~i.th proper procedures,.even.asbestos
cement can be applied with minimal release of fiber.
FMSI 02964
--------------------------
9
I cannot cmp~asizc too strongly t_he need for stringent controls
during demolition. 'fl10se listed here may not be adequate ond .close sur-
veillance should be maintained to verify the:!-r adequacy. For example, I
am not sure that any asbestos should be transported via chutes to trucks. I
It is hard to imagine that the debris would be completely wetted.
In reference to Section 6 A, I would like to raise some of the problems
assoca"ted with air monitoring which .may be severe. In ambient air samples 1
it is difficult, and often impossible, to identify asbestos fibers by
optical microscopy alone. There are many birefringent fibers with a simi-
lar appearance. Even the sampling of stacks containing only asbestos has its problems; Such sampling docs n~t evaluate a~y emissions from
windows., room exhausts or uncontrolled sources. Moreover, the use of optical microscopy can misestimate actual concentrations, e~~n assuming
accurate counting of all fibers longer than 5 microns. Often as many as
100 times more fibers shorter than 5 microns may be pr.esent. If those
i
I counted were a constant fraction of the total present, this would be no
l problem. However, such is not the case. In different uses of chrysotile
I we have found the ratio of the number of fibers longer than 5 microns to
! the total number to vary from 1/250 to 1/20.
Since bag
i I
houses have a size dependent efficiency, the results obtained by optical
a~alysis may be misleading and not comparable to other samples analyzed
1
I l
by similar means.
I The only way to accurately asses environmental exposures is by
l electron microscopy. Here, however, an analysis may cost $200 - $300 ',
i j and be ver.y time-consuming. You may wish to consider procedural controls
I
l
I
with the requirement of no. visib~e. emissions of asbestos from any building
I
or site. If the facility inspected questions the judgement of an inspector
they could pay for adequate air analysis by electron microscopy.
FMSI 02965
10
I enclose in Table IV data from ou.i work analyzing samples of nmbient
.'air from nearby 50 U. s. cities, These data show that a background of
some asbestos fiber is found in all cities, but occasional peaks appear.
From this occasional occuuence and from the fiber size distribution on high I
samples, it appears that the contribution of some specific source is
important in these high levels. Finally, one comment on the proposed ban of asbestos in brake
linings after 1975, The problem here is there is a dearth of information.
We have somevery preliminary information thfl.t asbestos air levels near
..
I
sites of extensive braking may be 3 times higher than background. Since
wind condi timis are highly variable, much more analysis of this question
is requ;ircd, All our data really show is that brakes are not as obvious
a problem as asbe-stos-containing fireprooofing spray in New York City.
Perhaps you may wish to qualify 7 B by the words "Unless evidence of
sofoty i.s dcmonstrntcd tho usa of osbosi;os .... "
In summary, your regulations in general ore oxcellont, your intent
is proper, and I.am pleased to stipport you.
'
I,
FMSt 02966
Table I
Observed and ExJ)ected Nwnbcr of Deaths Among 632 Asbestos Workers Exposed to
Asbestos Dust 20 Years or Longer, Jl943-1962
Cause of Death
19431947
Years .
,.
1948- . 1953..;
-152 1957
Total, all causes, . ; ... Ohsc:i:ved (asbestos worke~s) Expected .. (US white males).,
Total cancer, all sitcs ...... Observed (asbestos viorkers) Expected (US wl}i te males,.,
28 39.7
Io
51 .50,8
I.
'85 I 56,6
13 5 .7
17 8.1
26 13.0
19581962.
88 54.4
39' 9,7
Total, 19431962
255 203.5
95 36,5
Cancer of lung nnd pleura . Observed (asbestos workers) Expected (US white males)
..Cancc~.. of StOT!'HlCh 1 ~oJon ::1nd
~. l .. CC twr1, , , , , , , , , , , , , , , , , , ,
Observed (asbestos workers) Expected (US white males)
6 8 13 18 45 0,8 1.4 2.0 .. 2.4 6,6
\\
1
4'' 7
11
29
2,0 2,5 2.6 . 2.3
9',4
; Capcer of all other sites com-
i
i'
binccl ....... ..............
i. Observed (asbestos workers) 3 5 6 7 . 21
l
I
Expected (US white males) . . 2,9 4.2 8,4 5.0 20.5
f
I
I
Asbestosis ,
a
l Observed (asbes~os workers) 0 1 4 7 12
I
I
Death rates as report?d annually by the u.s. Nati.9nal Office of Vi tal
..Statistics. A five year average is given. here for each period.
Death rates inCflude cancer of lung, bronchus, pleura, mediastinWll and
trachea, assigned to international listcodo No. 17b-f prior to 1949
and to No. 160-164 thereafter.
... . .
. -~:
..
i.
.
~
.
" .... I.
.. ,..
;
t .:
<' .....
'
FMSI 02967
. .. '
.
Toblc II
...
.~ . ..
,;,, I
:' I
E:-:pcctcd nnd obse:rvcC. deaths a,-:-,ong 370 osbcstos
insulation wo:cker.s, Jan. 1, 1963 .i~o 30, 1971.
' -.
.... ....
Observed D:pcctcd
''a oaths
de.:ti:s*
Totcl c~nccr (all sites)
c~~cer of lur.g, pleura, tr~chea, b;onchus
92 47
.........15.1 -~ 5
+
I,
?lcural nesothclioma
-:.
...'.
Pcrito~c~l mesothelioma
. : .. ..
C~riccr o':;; stomach, colon and r9ctum .....:.-
Cancer all other sites
19
12 14
+ +eN, ...
+ 3.0 '.' '7 .6
: .JI.sbvstosis
.. . _.... All other causes
20
...
+ +
-
51.\\, 63.5
'
Total deaths
"....
..... J,G3
7S.G
...
...
-
... ... >i<E:qk:ctcd deaths nrc based upon ago specific rates io'r U.S. w!;i to males in 10S7. Smolcing habits arc disregarded . :
"rUnited States data not availoblo but :fiauro .should.bo only
'-: slightly less than 4.5.
;j:united States dato. not availablo' 'Ylut tho.so. aro rare .9ausos
of c,loath in general populati?n
. .'._' ......
... . '.; ~ .. ' ... , './ ..: .::;, ..::... ,; ...~.:~.... . ..:~.:.. .
. .:~. .:. ~:~~--.,.':":.:.:::. '
. . .: ... :. .', .. .. : ...... ;:~
:'< ': .,:;~... <-.:.,:.... :~......
':.~.' .-,:: '. '.' . ..... ..
' ...
..
i
... ... ... '
, ~ ', 1 I
'
,\
....
. '.'
'
. .
.,...
...
FMSI 02968
-- -- --~-- ---~------- ......------
-%,
Table II I
i.
\
I
j
l
i
l
.lIi _ _ __
Mortality experience of 632 members of IAHFIAW, Locals 12 and 32
January 1, 1943 to June 30, 1971
Cause of Death Lung cancer Pleural mesothelioma Peritoneal mesotheli.oma Gastro-intestinal cancer All other cancers
Total cancer = 188
Asbestosis All other causes
Number 85 7 20 40 36
32 205
425
Per Cent 20,0 1.6 4.8 9.3 8.4
7.7
48.2
100,0
!
\
i
...
l
!
Table IV
Asbestos Air Levels in United States Citie'.s
Analysis of 187 Quarterly Composite Samples
Asbestos Air Levels (lo-9 grams/m3)
Number of Samples With Given Vaule
0.0-0.9 1.0-4. 9 5.0-9.9 10.0-19. 9 20-49
50-99 ..
61 103
12 8 2 l
~
FMSI 02969
JAMES D. CALLAGHAN V.ce President
HILL AND KNOWLTON, INc. Publtc Relations Counsel
150 EAST FORTY- SECOND STREET NEW YORK, N.Y. 10011:
212-697-5600
ENVIRONMENTAL HEALTH UNIT
August 27, 1971
Dr. E.P. Stefl Vice President Raybestos-Manhattan 205 Middle Street Bridgeport, Conn. 06603
Dear Gene:
Bill Raines has asked me to send you the enclosed packet of materials dealing with brake linings to help in preparations for your meeting with Illinois Pollution Control Board personnel. For a quick rundown on what the scientific papers contain I am attaching to each of them a copy of the Summary and Evaluation sheets prepared at the time they were received in this office.
The papers enclosed are:
Bentley, M.L., "Control of the Use of Asbestos-Containing Friction Materials"
Hatch, D., "Possible Alternatives to Asbestos as a Friction Material" Hickish, D.E. and Knight, K.L., "Exposure to Asbestos During Brake
Maintenance" Knight, K.L. and Hickish, D.E., "Investigations into Alternative Forms
of Control for Dust Generated During the Cleaning of Brake Assemblies and Drums" Lee, G. L., "Removing Dusts from Brake Assemblies During Vehicle Servicing -- Alternative Cleaning Methods" Luxon, S., "Technical Implementation of the New Asbestos Regulations" Roach, S.A., "Hygiene Standards for Asbestos" Smither, W.J., "Asbestos and Asbestosis"
Although you probably have it, I am also enclosing a copy of the Lynch paper on brake linings. In addition you will find a selection of pages from a document, "National Inventory of Sources and Emissions: Cadmium, Nickel, and Asbestos - 1968. Asbestos, Section III," that deal with friction materials.
This report was prepared for the old Air Pollution Control Administration and was presented to them in February 1970. It has only recently become available to the public through a printing by the U.S. Department of Commerce Clearinghouse.
If we can be of any further help, please let us know.
JDC:runl
Enc. cc: W.P. Raines
\Sincerely,
~- Cal ]a ghan
FMSI 02970
SUMMARY AND EVALUATION
Subject: Brief discussion of the various forms of asbestos and their effects on health. Of some interest.
Evaluation: This very short paper, running to three printed pages, was
presented to provide background information to a conference on possible
asbestos exposure to maintenance workers on auto brakes and clutches in
Britain. The author points out that currently disc brake pads, brake
linings and clutch facings contain 50 percent chrysotile asbestos. However,
newer developments indicate that the percentage of asbestos in the mix is
likely to decline, perhaps down to a minimum of 30,percent asbestos. Disc
brakes require less asbestos fiber than drum brake linings, and it is
estimated that more and more passenger cars produced in the U.K. will
be equiped with disc brakes.
-- ---~- ~:_:_---~
---- Autho~:
Smither,
W.
--.., J.
(~rb)up
Medical
Adviser,
Cape Asbestos
Company).
'-__:___------
Jou~nal: Annals of Occupational Hygiene (British), January 1970.
Title: "Asbestos and Asbestosis."
Summary: As given ahove
-xxx-
FMSI 02971
,, i
!'
Ann. Onup. Hyg. VoL 13. pp. 3-!i. Pergamon Press 1970. Printed in Great Britain
t
l
ASBESTOS AND ASBESTOSIS*
W. J. SMITHER
Group Medical Advba, Cape Asbestos Company, 114 Park Street, London \V.I.
THE FORMS AND USES OF ASBESTOS
CoMMLRCIALLY important asbestos fibres fall into two main groups. The first of these is chrysotile, and the second comprises the amphiboles. Both groups arc . fibrous silicates, but they diD'er .in geological origin, in chemical composition, in molecular structure, in fibre size and strength, and in other characteristics. Chrysotile, white asbestos, comes from many different places. There arc slight chemical and physical variations in the fibres from different sources, hut basically all have the same
molecular ~tructure. On the other hand, the amphiboles comprise at least three
separate types, whose molecular structure is very similar, but whose chemical and physical properties differ more widely. .Amosite (amber) and crocidolite (blue) are of commercial importance in this country, whereas anthophyllite is a Finnish fibre not used here.
The relative amounts of each fibre in world production is shown in Fig. l and
the areas or main use in Fig. 2.
\
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f
i
f
I I
f
i
Asbetos. Annual world output -3,000,000 tons
Chrysoti le (white)
2,800,000 tons 93%
Crocidolite (blue)
(South Africa) 110,000 tons
3~o/D
Amosite (South Africa) 90,000 tons
3%
Anthophyllite (ron land)
10,000 ton~ ~o/o
Canada
USSR S.Nrica USA Europe
Others
1,250,000
7!>0,000 250,000 100,000 100.000 350,000
FIG. I. World production of asbestos.
*This paper was originally prc:;cntcd at a Conrcrence on Exposure to Asbc~tos during Brake
and Clutch lv!aintcnancc, held ;~t Brentwood, Essex, March, 1969. 3
FMSI 02972
.~: -~ -~,.~~~.;.............."~.;o..:.~.w...;;;~......~~~,~---~t.;;__,;c.~~-......,~~~:~.;;;;;.._....,:.;~,~:~.u;.... '
...
w.4 J. S~lllliER
Asbestos Annua I consumption 3,000 ,000 tons
Where it is used
Where it is mined
Othcrs
Chrysotile
Belgium Italy
France JAPAN
UK
Germany
Others
USA Southern Africa
USSR
USA
USSR
Ganado
1
Blue Grocidolite
j s.~t,ca
Amos1te
lS.Africa
FiG 2. .t\rcas of usc of asbestos.
Anth ophyll1te Fi nlcnd
=r-:-:
The diflcrent characteristics of asbestns fibres dictate their u~cs, their applications and their mode of packing and handling. For example, aHwsitc can be prcr,~urc
packed and pal!ctized, whereas chrysotilc lends itself more readily to containerization. By far the grcatc~t usc of chrysotile is in the a<.bestos cement industry. Amositc is used mainly in insulation and building product.;. Crocidolite, due to its excellent acid
resistance, finds its major application in the manufacture of battery boxes in 'this country. It is added to the pitch mixture in tllhlpcncd dissoluble bags.
Ver brake 1 contair in the f percent now cc with ar pads fo It is est be equi
The is the ~ physit:a is being the fibn
. The lining o cavity. becomi1
Alit period t sists or interfere the shor
The: calcium concentt any eVCI itself.
Expu of !he Ju mesothcl workers uncomn> frequent! The n.:a' invcstig:t
FMSl 02973
'
\
-.
),.;_~,;!.~~~~.."}. ,'-".-...J._;_~,.cl.:..;:....:~.;;_,~-~~~~2.ot.~ai~ 'iiri.tt"W,-'' ~~~;~-~.,;:.:..o...--w:~&..:.;~~....t,..,.~:.~,u"!i?j'' f\.f.it>"'""-~..~i:we~~~~~..
'lications pressure
~rization.
nwsite is llcnt acid :s in this
Asbestos and asbestosis
5
Very broadly it can be said that current friction materials, whether they be disc brake pads, passenger car and commercial vehicle brake linings or clutch facings, contain 50 per cent chrysotile asbestos. The new trends of development, particuiarly in the fields of disc brake pads and commercial vehicle brake linings; indicate that the percentage of asbestos included in the mix is likely to decline. Some new materials now contain approximately 40 per cent asbestos, and newer mixes can be foreseen with an even lower percentage, probably down to a minimum of 30 per cent. The pads for disc brakes require less asbestos fibre than conventional drum brake linings. It is estimated that more and more passenger cars produced in the U.K. will in future be equipped with disc brakes, particularly on the front wheels.
THE BIOLOGICAL EFFECTS OF ASBESTOS
The variation existing in the biological effects of the different types of asbestos is the subject of considerable interest and research, and the extent to which the physical and chemical characteristics of the asbestos itself influence biological effects is being investigated. The role of trace clements and contaminants associated with the fibres has also to be considered.
The chief biological effects of asbestos are confined to the lung and the pleura, or lining of the lung and chest c<lvity, and to the peritoneum, or lining of the abdominal cavity. A few cases of skin corns have occured in asbestos workers, but these are becoming much less commo:1.
All types of asbestos, if inhaled in fairly high concentmtions over a considerable period of time, may cause fibrosis of the lungs. This disease, called asbestosis, consists of thickening of the lung membranes with resultant stiflcning of the tissues and interference with oxygen uptake. The interference with gas transfer is the 1'eason for the shortness of breath which causes the disability associated with asbestosis. The amount of exposure required to produce fibrosis of the pleura, with or without caJ.cium deposition in the scars, is more debatable. It may be that shorter, less concentrated exposures, particularly in youth, leave this mark upon the pleura. In any event this particular cflcct of asbestos inhalation causes little or no disability in itself.
Exposure to asbestos may lead to further complications, e.g., heart failure, cancer of the lung, or, rarely, to malignant changes in the pleura or peritoneum, known as mcsothcliom::1. Cancer of the lung has been shown to be more common in asbestos workers who smoke, just as it is in the geno.:ral population. Mesotheliomas are very uncommon throughout the world, but in some areas they have been associated more frequently with exposure to crociclolite than to chrysotile, amosite or anthophyllite. The reasons for this arc at present obscure, but arc being sought intensively by in;cstigators in many different countries.
FMSI 02974
.. '
r. ,
'
SUMMARY AND EVALUATION Subject: Asbestos dust control standards in Britain and the U.S. and their relationship to occupational health. Of some interest. Evaluation: This paper is essentially identical with the one presented by the author at the Conference on "The Control of Asbestos in the Working Envirol111j.ent," sponsored by the British Occupational Hygiene Society and the Asbestosis Research Council, London, June 18, 1969. That paper has previously been evaluated and distributed. The author is president of the British Occ~nal Hygiene Society.
~)
Author:( Roach, s. A. (London School of Hygiene and Tropical Medicine). /
/' Journal: A~nals of Occupational Hygiene (British), January 1970 Title: "Hygiene Standards for Asbestos." Summ~~: Hygiene standards of the BOHS are discussed and compared with those of the ACGIH. The British standards apply only to chrysotile, and recommend a lower TLV than the latest recommended by the ACGIH.
-XXX-
FMSI 02975
.~,!!.~:-w~~~...oo..J.-..I.f,..:._-,...,.._.,..,:~~......JYJ...:.~~--~~"'.:.~~~~~.._...U..... ~~-~~~\J:..:d,.~l_._;.o,..,.,,.l...U,..:..t"'j,~.:a.,~;~~..,j..~b,.;..wi~~<L..>-,w..,i...:.;..,..
.' . .
Ansr. Occup. H)g. VoL D, pp..7-JS. Pcrgdmon Press 1970.. Printed in Great Britain
~
I
I
HYGIENE STANDARDS FOR ASBESTOS*
s. A. ROACH
London Schoo! of Hygiene and Tropical Medicine, Keppel Street, London W.C.I.
As LONG as there is any airborne asbestos dust in the work environment there may be some small risk to health. Nevertheless exposure up to certain limits can be tolerated for a lifetime without incurring u:1due risks.
A hygiene standard for asbestos was published in the U.K. by the l\finistry of Labour in I960 and was taken from the annual list of Threshold Limit Values of the . American Conference of Governmental Industrial Hygienists (ACGIH) (Committee on Threshold Limits, Annually).
The British Occupational Hygiene Society formed a Hygiene Standards Committee in 1965 t0 advise on hygiene standards. This Committee recommends the use of the ACGIH list of standards and supplements this with critical examinations of ACGIH and other standards considered unsatisfactory by British workers. The Hygiene Standards Committee has expert Sub-Committees, each of which is concerned with a specific standard. There is a sub-committee on asbestos dllSt in air, one on trichloro::thylcne vapour and its urinary metabolites, one on airborne vegetable dusts in the textile industry, anollwr on noise criteria for hearing conservation and two new ones arc coming into being; on cadmium oxide fume and silica dusts in air.
It is important to take into account the economic consequences of any recommendations made as well as the benefits to health, and this is one reason why on each of these Hygiene Standards Sub-committees, scientific and medical experts from industry are included. The value of a standard rises in proportion to the number of people who become protected by it. A particular advantage of direct industrial reJ)resentation on h~gicne standards committees is that the industry more rcndil~ identifies itself with the standards recommended.
The Hygiene Standards Sub-committe~: on Asbestos, under the Chainnanship of Professor Lane, h;:s developed new hygiene standards for airborne chrysotile dust (LANE et a!., 1968). These were based on the results from a medical and environmental study at an asbestos textile factory in England, in which investigations were made on 290 of the men employed at this factory in the period of 1933-1%6.
The Sub-committee considered that the degree and nature of the risk associated with the standards should be specified and the method of the derivation of the standard from the data presented should be described in detail. It was also considered that the standards should give prominence to the gwc.lually incrca~ing risk in relation to the concentration rather than to the single figure threshold concept. Open recognition should be given to the possibility that people might be adversely ~,fTectcd, even
This paper was ori~inally presented at a Conference on Exposure to Asbesto~ during Brake and Clutch Maintenance, held at Brentwood, Essex, :'>.hrch, 1969.
7
B
I
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f
f
f
~
i
i
I
t
FMSI 02976
..
-.
8 S. A. ROACH
when the recommended standards of air cleanliness arc maintained. It was recognised
that to protect the hypersusceptible workers environmental control would have to be
supplemented with medical examinations.
It was evident from the data made available to the Sub-committee, and from the
earlier American experience, that when concentration is held constant the prevalence
of asbestosis was highest r.mong those with the greatest duration of exposure. Over
a period of time, dust accumulates in the lungs and gives rise to asbestosis. However,
some of the dust is removed from the lungs, for example, by being dissolved. Con-
sequently, if it is assumed that none is removed and exposure is limited accordingly,
a safety factor is thereby incorporated. The problem of relating prevalence with concentration and with duration of exposure was resolved by assuming that the cumulative amount of asbestos remaining in the lungs from a given exposure is equally dependent on the dust concentration and on the duration of exposure to that concentration.
The asbestos dust concentration had been measured at the textile factory concerned with several different instruments, including the membrane filter method, in which the number of fibres longer than 5 fl. was counted. The dust concentration to which different workers had been exposed varied from 1 fibre/em to 27 fibresfcm over periods from 10 years to 33 years.
The exposure of an individual was expressed as fibre years/em', that is, the product
I
t
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I
of the average concentration to which he was exposed during working hours and his
years of exposure to this average. A curve was developed relating the prevalence of
asbestosis to exposure expressed in this way. The principles on which this was based
may be explained as follows.
An indiv!dual's re&ponse to dose of any foreign substance can be expressed by a
line (Fig. 1). There is a dose which produces no response whatsoever. This is marked
by the threshold A. If the individual is given progressively higher doses, the r0sponse
progresses correspondingly. The least positive response may bs real but merely.
undesirable. A higher response may have sensory manifestations. A still higher
1 l
response might be associated with observable physiological changes and overt clinical
effects. The highest responses of all would perhaps be signified by loss of conscious-
ness, or even death.
The degree of response may be conceived to be measurable objectively on a con-
tinuous scale starting at zero, and the scales of dose and response could be chosen
to linearise the relationship between them, as in Fig. 1. The dose-response relation-
ship could then be described by the slope of the line and the point where the line
strikes the dose axis. The slope of the line expresses the rapidity with which increases
in dose produce increases in response in this individual. The steeper the slope the
greater the safety factor necessary in practice to allow for the inevitable occasional
excursions oT dose above the maximum desirable.
Doses which 6ive zero response arc never, in fact, known with absolute certainty
since the sensitivity of measmcments of response is limited. A response which can
just be detected in a man corresponds to another and higher dose, shown as threshold
B on Fig. 1. Also, one is not normally considering just one individual. As with all
other characteristics of man, the position and slope of a dose-response line varies
from one individual to another. Each man's dose-response line is different with a
different 1 is represc average 1r
In a n about an: frequency on either s
In a rc Exactly wl usually no affected by the size fr( zero expos
An air of men bein can be mad standard h: costs of air
A Cllf\'C
clinically an
their years' Fig. 3. The
FMSI 02977
-."-.
rcct .sed have to be
J from the prevalence ure. Over However, .-cd. Concotdingly, cnce with ~ that the is equally that con-
tory conlethod, in tration to 'ibresfcm
t: product sand his ;lienee of
tas based
;sed 1-v a ;m, d response t merely ll higher t clinical nscious-
n a con; chosen ":.;.,lionthe line ncreases lope the casional"
ertainty 1ich can 1reshold
with all
~ ..1ries with a
Hygiene standards for asbestos
Individual response to dose
9
..
.1:
0
.D,.
0::
Threshold B
~----------------
_v Threshold A
Dose
FIG. 1. Individual response to dose.
different threshold dose and a different slope. A particular population under study is represented by a family of dose-response Jines centred around the line for the average man. "
In a real population the threshold dose will vary froi"n one individual to another about an average value, as in other medical norms. It is to be expected that the size frequency distribution of threshold doses would be a hump-shaped curve tailing away on either side of the central value, as shown in the Fig. 2a.
In a real field study it is established whether a man has or has not been affected.
Exactly when or in what concentration he ftrst developed tht: characteristic response is usually not known. A graph sho\ving exposure against the total number of people affected by it would be a cumulative sigmoid curve, illustrated in Fig. 2b, derived from the size frequency distribution in Fig. 2a. This tails away down to zero response at zero exposure.
An air quality standard is still associated with a small but non-zero probability r.~men being affected by the contaminant in question. The risk of people being affected can be maCe as small as one wishes. Zero risk is the ultimate target and an air quality standard has to be a compromise between the costs of bearing a health risk and the costs of air contaminant control.
A curve was fitted to the data from the textil" ~::c:.,: vt asbestosis, detected clinically and the exposure in fibr" :.':;, ,,..;, "-:' ul all the inclivicluals under study over their years of. employment up tc, 1966. The bottom end of the fttted curve is shown in Fig. :l. Tl:: ihrc~ points relate to three of the groups of workers studied. The exposure
f
f
f
I
FMSI 02978
,. .
10 S. A. RoACH
Population response to dose
.
E
0
~
0. .
..E
>.
....c.
'.i.
o.:.>,
>
:0
c
.0 ~
.0
E
z:>
Threshold dose
FIG. 2a. Population response to th.rcshold dose.
..
E
2
..a.
E
>.
.c
:t:
3: .!!!
.:0.>, :2:
"0
.!:
0
-~
i ..1> E z:>
Dos~
Flo. 2b. p,,;.ulation response to dose.
I
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I i is shown on
prevalence i! basal rales.
Basal ral' 'and there is posure. On! rales.
A proble1 said to be ab moo by ever) exposure. Tl other similar it to zero. It benefits to th cost of dust c be economic, The benefits taminant expc benefits to the
One conch an accumulatt: affected to the is, for exampl<
FMSI 02979
.-~Liili;~..."'"~.Ni:.o~.'.
-... '
Hygiene standards for asbestos
40
-...; 30 ~
...n
.0
-0
..~
c
20
...u'0:
.c"E'
~ 10
:.
Response to chrysotile asbestos exposure
, ,,,,,,,,'
/
11
~~~----~zs~o~------~5o~o~------~7~5~o~------~,o~oo
:: Exposure (fibre years/em') Fro. 3. Rcsponse)o chrysotilc asbestos exposure.
is shown on the horizontal axis, expressed in fibre years per em and the corresponding prevalence is on the vertical axis, showing the proportion of people with crepitant basal rales.
Basal rales is the earliest clinically demonstrable efTect on the lung due to asbestos and there is a steadily increasing prevalence of basal rales with increase in dust exposure. Only groups with ncar zero dust exposure show zero prevalence of basal rates.
A problem arises when it is appreciated that there is no exposure which can be said to be absolutely free of risk. There is no single threshold exposure held in common by everyone. There is, consequently, this gradually increasing risk in relation to exposure. The application of dust control to meet a TLV, an MAC, MAK value, or other similar hygiene standard will limit and control the risk but is unlikely to reduce it to zero. It has to be remembered that asbestos is very widely used and brings real benefits to the community at large. A standard could be made so stringent that the cost of dust control is prohibitive, that the production and usc of asbestos ceases to be economic, production and use is discontinued and the associated benefits are lost. The benefits gained by reducing the risk of asbestosis through reducing air contaminant exposure have to be weighed against the possible loss of direct and indirect benefits to the community from the usc of the material.
One conclusion from the exposure-response curve filled to the data was that for an accumulated. exposure of 100 fibre years/em, it is probable that the risk of being affected to the extent of having early clinical signs will be less than I per cent. That is, for example, a concentration of 2 fi.brcsjcmJ for 50 years of such exposure while
I
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s.12 A. ROACH
at work, 4 ftbresfcm' for 25 years, or 10 fibres/em' for 10 years. The British Occupa-
1 tional Hygiene Society Hygiene Standards Sub-committeeon Asbestos expressed the view that a proper and reasonable objective would be to reduce exposures to below
I1 this level and thereby reduce the risk of contracting asbestosis to less than 1 per cent of those who have a lifetime's exposure to the dust. For such workers, who may possibly work for 50 years, the long term average concentration to which they arc
l exposed would need to be less than 2 fibres/em'. For others, who will be exposed to
!. asbestos dust in air for shorter periods, the long term average concentration need not
1 be so low, as long as their exposure will amount to less than 100 ftbrc years/em'. The possibility was considered that short periods of very high concentration for a
few weeks or less might be disproportionately important in determining the risk of
asbestosis. However, the evidence for this was not conclusive and the committee
were satisfied that the risk can be satisfactorily expressed with respect to an average
concentration over 3 months and can safely be kept below 1 per cent by ensuring that
a man's accumulated exposure does not rise above 100 ftbre years/em'.
The exposure measured by making fibre counts on membrane filter samples can
be converted into exposure measured with an impinger, the American method, by
examining the results of side-by-side comparisons of the two instruments. Such
comparisons made by the United States Public Health Service in asbestos textile
plants have shown that an accumulated exposure of 100 ftbre years/CJn' corresponds
to 15 million particle years/ft' by standard impinger methods (AvER, LYNCH and
FANNEY,.l965). The present American Threshold Limit Value is a concentration of 5
million particles/ft' (mpjft') which, if it persisted, would result in an accunmlatcd
exposure of 250 million particle yearsjft' over 50 years.
These American hygiene standards, calkd Threshold Limit Values, arc a system
i for summarising published information on air contaminants in a convenient form
1 for the day-to-day practice of industrial hygiene. The present American standard for 8-hr averages is thus 17 times higher than the British standard for 3 monthly
~i
1
averages. However, there is a published intention to revise the American standard in view oj; recent knowledge.
However, the difference between the American and British standard is not pri-
1 marily due to conflicting ev;dencc on the adverse affects of asbestos. It is because of a
j< different attitude now adopted over the degree of protection which ought to be given against asbestosis.
j The American Threshold Limit Value of 5 mp(ft3 was reconunended by Dreessen and his co-workers in 1938 after studying 541 employees in 4 asbestos textile plants
i where massive exposures to chrysotile occurred (DRESSEN eta!., 1938). Only 3 doubtful
i
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cases of pneumoconiosis were found at the time of the study in those exposed to dust
l concentrations under 5 mp/ft', whereas numerous well-marked cases were folmd above 5 mp/ft'.
j A conference helc\ in 1965 on the biological effects of asbestos called attention to
the very real probability that the 5 mp/ft' limit recommended by Dreessen is inade-
1
quate to give complete working-lifetime protection against all forms of asbestos (SCHALL, I 965). Medical data on which the limits had been based were inadequate;
'i more than half o( the asbestos workers studied by Dreessen and his co-workers were
under 30 years of age and thus had insutlicient exposure time for much asbestosis to
develop. 5 years a1 time" stw in the ove
The Br after stud the ACG Limits, 1 while tak and cons: of the he: that the . years, a p
In ac( below wh average c often cot recommc length an by Jmpin 12 fibres/ of as best(
The i, to them s given tb" to take a.
The s person's years/em' clinical si these sta1 associate'
The s over 3m equals 2 this valEt higher th mum 12 complian
standard~
Inspccto\ judgmrni mum for pror:tbili
There dusts fro
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FMS\ 02981
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.h Occupa1rcssed the s to below I per cent who may h they arc :xposed to n need not em. 1tion for a he risk of committee tn average .uring that
mplcs can ethod, by Jts. Such tos textile rresponds t'NCH and at ion of 5 :umulated
a ~... ..:m ient form standard monthly standard
; not pri~ause of a ~ht to be
Dreessen .ile plants doubtful <.1 to dust -re found
rntion to is inadcasbcstos !dequate; ~crs were c:~tosis to
Hygiene standards for asbestos
13
develop. Of the 105 workers exposed to less than 5 mpjft, 82 had worked less than 5 years and only 4 had more than 10 years exposure. fvforeover, it was a "point-intime" study; many of the ill were missing, the dead uncounted, and were not considered in the over-all evaluation of the limit.
The British Hygiene Standard5 Committee finalised its views in November 1967 after studying the British data, and these views were immediately communicated to the ACGIH. TLV committee. In May 1968 the ACGIH (Committee on Threshold Limits, 1968) proposed dwnges to its hygiene standard. The new asbestos limit, while taking into account the British views, had to be based on American experience and considerations applicable to the American industrial scene. Recent evaluation of the health experience in asbestos plants in tile U.S.A. had, nevertheless, indicated that the 5 mp/ft' limit was not sufilcicntly low to protect workers exposed for 30 years, a period rarely exceeded in America.
In accordance with these findings, the 5 mp/ft' limit was made a ceiling value below which all concentrations should fluctuate. This corresponds to a time-weighted average concentration over a shift of 2 mp,'fP. Since the count by Impinger procedure often consists primarily of extraneous particulates, au alternative fibre count was recommended, using the membrane filter method in which fibres greater than 5 I' in lengtp are counted as in Britain. On this basis, for a time-weighted 8-hr average limit by Impinger count of 2 mp/ft', the corresponding limit based on the fibre count is 12 fibresjcm 3 This limit is intended to reduce to an insignificant risk, the occurrence of asbestos disease ::nnong those exposed for 30 years to all forms of asbestos.
The intended changes in American TLVs give two years' notice and objections to them should be conveyed to the TLV committee of the ACGIH. All objections arc given the most serious and sympathetic consideration and users are strongly r:dviscd to take advantage of this if they have reason to question the proposed changes.
The standards of the British Occupational Hygiene Society recommend that a person's accumulated exposure to chrysotile asbestos should not exceed 100 fibre ycarsfcm3 It is probable that the risk of being affected to the extent of having early clinical signs of asbestosis will be less than l per cent if the conditions comply with these standards. It is believed that this is the first time a hygiene standard has been associated with such a specified degree of protection.
The standards refer essentially to an average concentration during working hours over 3 months of 2 fibres/em'. In an envimnment where this 3 monthly average just equals 2 fibres/em, the concentration within this period will sometimes be above this value and sometimes below. The maximum 8-hr aventge will thus be somewhat higher than 2 fibres/em'. The proposed change in the American TLV is to a maximum 12 fibres/em 8-hr average, which if exceeded ~1n a shift demonstrate~ noncompliance. Thus, there may be a rough degree of consistency between the hygiene standards from the two countries' organisations, so far as !his is possible. The Factory Inspectorate in their work have often only a short time during a day to come to a judgment on conditions and arc considering a development of this, applying a maximum for even shorter periods, of a few minutes, which if exceeded would indicate a probability that the Asbestos Regulations are not being complied with.
There is a growing body of information on chrysotilc dust and other asbestos dusts from many countries, and it is hoped that in future the views from difiercnt
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'
parts of the World will be sought so that standards for tes~ing air cleanliness can, as
grasp mon
far as possible, be held in common. Even so, the risks that may be tolerated can vary
kind of inf
from country to country and from one situation to another within a country.
be able to'
The air quality attained in industry in ditTercnt countries docs tlitTcr and, no doubt,
This de
will continue to differ. A wealthy country can afford to spend more money on air-
equation, r
contaminant control. Also, a country very conscious of the slightest risks to which
dard. Ho\
its workers may be exposed through their occupation may be expected to have different
standards from one which is not, where other health risks may be so much the greater.
The benefits to the community from the use of inexpensive asbestos products have in some measure to be weighed in the balance against the benefits to the health of the workers that would accrue by reducing asbestos dust exposure.
The British Occupational Hygiene Society Sub-committee on Hygiene Standards for Asbestos has not yet decided whether their chrysotilc standards would be suitable for arnosite or crocidolite dust, nor whether they give sufficient protection against hmg cancer or mesotheliomas. The ACGlH, on the other hand, make no distinction between ditTcrent types of asbestos in their standards. In this country it should be remembered that the Senior Medical Inspectors' Advisory Panel on Problems arising
AYER, H. E.,
CoMMITTEE c
Trans. A Ohio, U.~
COMMITTEE 0
Governm DREESSEN, W
and TRICI wasll. Nc LANE, R. E., occup. liJ
from the use of Asbestos considered that the evidence to date on balance indicated that a particular significance must be given to crocidolite as a cause of mesotheliomas (Minist1y of Labour, I 967). That Panel recommended that other types of fibre
MINISTRY Of
Medical! SCHALL, E. L
should be substilutcd for crocidolite w!1crever possible and where this is at present
impossible .special precautions should be taken to reduce the risks of inhaling the
material to the lowest possible level. \Vhatever measures may be adopted to control
asbestos dust, the Panel urged that these be even more rigidly applied to crocidolite.
The Factory Inspectorate is also developing procedures for testing hygiene standards
in factories and i> seriously considering the adoption of especially rigid requirements
..-where crocidolitc is used.
To derive hygiene standards for an air contaminant which provide a known
degree of protection against a health hazard, it is necessary to have a body of data
showing the ~1mount of air contaminant to which people are exposed and the corre-
sponding effects or Jack of them in the people. It is also necessary to have a grasp of
the consequences to industry and users of limiting and controlling emissions of the
contaminant. Our present information is very imprecise, particularly in terms of the
j practical consequences of specific hygiene standards. In developing recommendations for a hygiene standard, the British Occupational Hygiene Society Sub-committee
found that knowledge of the relationship between exposure and risk was not the
. greatest area of uncertainty. A much more difficult and contentious problcm was to
decide on what, in fact, was <ln acceptable level of dust control.
More information is needed, for example, ori the expense of dust control. Where this is done by ventilation it is important to know what is the minimum amount and
l I
j what kind of local exha.ust ventilation and dilution ventilation is necessary to achieve ,,l' a given degree of air cleanliness in a work place, since costs tend to climb as the cube
Ief the air flow.
( Research is needed to determine the balance between local and general ventilation
I which produces a speciJied degree of control at minimum cns.t. By setting rlswll the
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capital cost, installation cost, running and maintenance costs, it becomes possible to
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FMSI 02983
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i1CSS can, as d can vary ry. I. no doubt, ncy on air.;~ to which ,ve ditrerer.t the greater. )ducts have ealth of the
:Standards be suitable ion against distinction . should be ~ms arising e indicated otheliomas ;:s of fibre at present 1haling the to control :roc 1ite. : stanoards quirements
a known dy of data the conea grasp of tons of the Tms of the lcndations committee as not the lcm was to
ol. Where nount and to achieve the cube
\l'ntilation :down the possible to
Hygiene standards for asbestos
15
grasp more firmly the consequences of adopting particular hygiene standards. This kind of information is needed throughout the field of asbestos dust control so as to be able to weigh up the costs of achieving high air cleanliness.
This does not reduce the choice of an air quality standard to a mathematical equation, nor does it avoid the need to exercise wise judgment in the choice of stan.dard. However, the judgment can become a little less arbitrary than at present.
REFERENCES
AYER, H. E., LYJ'CII, J. R. and FANNEY, J. H. (1965) Ann. N.Y. Acad. Sci. 132, 274. CoMMITIEE 0:-.1 THRESHOLD LIMns (1968) Supplemental Documentation of Thresiwld Limit Values.
Trans. Am. Conf. Governmental Industrial Hygienists 1968, p. 188. 1014 Broadway, Cincinnati,
co~lOMhIiToI,EEU.OSN.AT.HRESHOLD Ll~IITS (1969) Threshold Limit Values for 1969. American Conference of Governmental Industrial Hygienists, 1014 Broadway, Cincinnati, Ohio, U.S.A.
w..DREESSEN, W. c . DALLA VALLE, J. M., EDWARDS, T. I., !\liLLER, J. SAYEI'.S, P.R. EASON, H. F.
and TRICE, M. F. (1938) A study of asb"stosis in the asbestos textile industry. Pub!. Hllh Bull.,
Wash. No. 241. LANE, R. E., BARNES, J. M., HrCKISIJ, D. E., JONES, J. G., RoACH, S. A., and KtNG, E. (1968) Ann.
occup. lfyg. 11, 47. MINISTRY OF LABOUR (1967) Problems arising from the usc of asbestos. Memorandum of the Senior
Medical Inspec'tor's Advisory Panel, HMSO, London. SCHALL, E. L. (1965) Ann. N.Y. Acad. Sci. 132,316.
FMSI 02984
-'..
' i.
SUMMARY AND EVALUATION
Subject: Study of asbestos dust exposure among British auto brake mechanics. Of interest and importance.
Evaluation: 'This paper sheds additional light on the persistent speculation concerning brake linings and asbestos dust. The study was conducted among workers engaged in the repair and maintenance of brake drums "at the Service
I
Bay of a Ford Main Dealer in the Greater London area." During the dustiest part of the operation, the preliminary cleaning of the brake drum, workers were exposed to an average of fewer than two fibers per cubic centimeter of air. According to the recommended dose-time limits established by the British Occupational Hygiene Society, this means that a brake-maintenance worker could work for 50 years at this job with less than a one percent risk of contracting asbestosis.
Journal: Annals of Occupational Hygiene (British), January 1970.
Title: "Exposure to Asbestos During Brake Maintenance."
Summary: Brake lining mechanics in an automobile service shop worked on two passenger cars and a truck, while two types of dust-measuring devices counted the amount of asbestos dust in the atmosphere. The personal exposure of the mechanics was below the limit corresponding to 50-year exposure, the hygiene standard of the Brit:ish Occupational Hygiene Society. "Samples of drum dust
were examined by Dr. s. Holmes, and his tests showed that chrysotile was pre-
sent only in trace quantities, or at most at 1 per cent, compared with the original lining content of 40-60 per cent. These findings suggest that there is a change in the physical and/or chemical form of the asbestos during its use as a brake material."
-xxx-
FMSt 02985
1970J anilaryAnn. Occr~p_. llyg. Vol. 13, pp. 17-21. l'ergamon Press 1970. Printed in Great Britain
EXPOSURE TO ASBESTOS DURING BRAKE / MAINTENANCE*
/
D. E. HtcKISH and K. L. KNIGHT
Medical Services, Ford of Britain, Brentwood, Essex
EXPOSURE DURING CAR SERVltlNG
THERE is little maintenance of passenger vehicle brakes involved at the manufacturers' premises, and therefore an investigation was carried out at the Service Day of a Ford Main Dealer in the Greater London area. This Dealer normally senices 10-20 cars per day, but blowing-out of brake shoes and drums is not included in all r9utine services. It is the blowing-out procedure which is the subject of the study.
Air.sampling was carried out using membrane filters, the sampling and subsequent assessment being in accordance with the technique described in the Hygiene Standard for Chrysotile Asbestos Dust, published by the British Occupational Hygiene Society
(1968). Static samples were taken by the side of.the car (Fig. 1) and composite samples
were also taken in the dust-cloud during the blowing-out procedure, continuing by the side of the car for the remainder of the sampling period. Normally the mechanic takes care to blow the dust away from himself, so this sampling procedure should overestimate exposure. Two sampling periods of 45 minutes were used, and during the first period one Cortina Est<:te and one Anglia Van received brake blow-outs, and dut;ing the second period one Cortina car was dealt \vith. The results are shown in
Table I.
'I:'ABLE I. ATMOSPHERE SAMPLES DURING CAR BRAKE SERVICE
Location of samples
W period
Fibres/em 2nd period Time-weighted
average
By car Dt.:st cloud then by car
l-12 111
142 362
125 255
An estimate of the daily exposure of the mechanic engaged on brake cleaning was oblained by a series of personal sample;. (Fig. 2) eovcing an entire workshift, during which brake ser\'icing was carri.:.-.: uul on 11 vehicles. The results arc shown in Table 2.
"'This p::pn was originally presented at a Conference on Expo~urc to Asbestos during Brake and C".1tcJ. Maintenance, J.clu at Brentwood, Essex, March, 1~69.
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FMSI 02986
18 D. E. HICKISII and K. L.' KNIGHT
TABLE 2. PERSONAl. SAMPLES DURING CAR
BRAKE SERVICE
Sample
1 2 3 4
s
6 Timewcighted average
Concentration (fibres/em)
063 H2 021 096 038 079 068
EXPOSURE DURING TRUCK- SERVICING
Maintenance of truck brakes involves a somewhat different type of operator
exposure as the servicing is more complex, and therefore the number of vehicles dealt
with is Jess. The larger size of wheels and drums, on the other hand, makes it difficult
for the operator to avoid the dust cloud produced, and personal exposure could be
higher than that during car maintenance. Further sampling was therefore carried out
in a large fleet workshop with equipment similar to that used for the passenger car
tests.
Static samples, each of approximately 3 hr duration, were collected during the
morning and afternoon periods at three positions; at the bay adjacent to the one
at which brake cleaning was carried out, at the next bay, and in the centre of the garage.
Brakes were blown out during the morning, but not during the afternoon. The results arc given in Table 3.
lABLE 3. GENERAL ATMOSPHERE SAMPLES DURING TRUCK BRAKE SERVICE
Location of sample
Concentration (fibres/em)
l Adjacent bay
Morning Afternoon
028 007
2 Days away
Morning
017
Afternoon
007
1 Centre of garage
Morning
0-49
Afternoon
011
Personal samples W!rc obtained from two men-the man engaged on brake cleaning, and the man engaged on clutch repair work at the adjacent bay. The first
I period of 15-2 hr included the period of brake cleaning, and the second period of approximately 5 hr represented the remainder of tl1e shift. The results are shown in Table 4.
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FMSI 02987
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Exposure to asbestos during brake maintenance
TABLE 4. PERSO:-ciAL SAMPLES-TRUCK BRAKE SERVICE
Operator
Concentration (fibrcs/cm3)
Brake cleaner during cleaning after cleaning
Time-weighted average
Clutch repair-adjacent bay during cleaning after cleaning
Time-weighted average
7-09 008 1-75
225 011 079
19
SIGNIFICANCE OF EXPOSURE LEVELS
The Hygiene Standard suggests that exposure should not exceed an accumulated level of 100 fibre-years/em. On this basis, a man exposed for the whole of his working lifetime of 50 years, should not be exposed to concentrations exceeding 2 fibres/em. While an exposure to asbestos of this length is somewhat improbabk in the case of motor mechanics, nevertheless the results have been interpreted against this value, and the findings are summarized as follows:
Car servicing While the standard may be exceeded in the dust cloud during aclual brake clean-
ing, the personal exposure of the operator studied was well below the standard.
Truck servicing The standard is not exceeded during brake cleaning in the general atmosphere
away from the immediate vicinity of the operation, but personal cxposHres in the vicinity_ do exceed the standard. On a daily basis, the personal exposure levels arc below the standard, although that of the brake cleaner approaches it.
It should be noted, however, that in a fleet workshop, brake cleaning operations do not necessarily take place daily.
THE NATURE OF AIR-BORNE DUST
Brake lining materials contain 40-60 per cent of asbestos, and it was somewhat surprising to find that particles of a fibrous nature were scarce in the air samples collected. In a laboratory investigation, specimens of dust were obtained by ftling brake lining material, and after sieving through a 200-mcsh sieve, these were examined microscopically before and after incineration. Samples of dust were colleckd from brake dmms during car servicing and examined in similar manner.
The results of the examination were expressed as the percentage of particles which were fibrous in nature, and arc compared in Table 5, together with a result from an incinerated thermal precipitator sample obtained during brake clcnning.
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20 D. E. HICKISII and K, L. KNIGHT
TADlE 5, AssESSMCNT OF FJDROUS fRACTIONS OF DUST SAMPlES
Sample
Percentage of pa rticlcs
seen to be fibrous
Sample
Sample
not incinerated
incinerated
Brake lining material
Brake drum dust Air-borne dust
28 12-3 06 1-6
13
It is clearly shown that the percentage of fibres in the drum dust and airborne dust is much lower than that in the dust formed from the original lining material.
Samples of dn1m dust were examined by Dr S. Holmes, and his tests showed that chrysotile was present only in trace quantities, or at most at I per cent, compared with the original lining content of 40-60 per cent. These findings suggest that there is a change in the physical and/or chemical form of the asbestos during its use as a brake material.
Enquiries were made of research workers in the UK and USA as to whether they had observed a similar effect. LYNCH (1968) reported that tests on brake testing dynamometers had shown the presence of few or no fibres in the dust produced from bliS and automobile brakes, except under severe braking conditions. In the latter instance, the brake' temperature reached 320-370C, compared with the design maximum temperature of 290-320"C, and it appeared that, under these conditions, the binder decomposed and released part of the asbestos as free fibre. At lower bulk lining temperatures within the normal operating range, the binder behind the surface remains intact. However, the spot temperature at the point of contact between the lining and the drum may be higher than the decomposition temperature of asbestos. The decomposition product, therefore, includes not free asbestos fibres but a difTerent mineral, resillting from thennal metamorphosis.
HoLMES (1967) in reporting the analyses described earlier in this paper, commented that the normal thermal decomposition product of chrysotile is forsterite, a non-fibrous crystalline magnesium s:licate. However, our samples of brake dnun dust contained very little forsterite, but rather were mainly comprised of an amorphous magnesium silicate, which is non-fibrous. Little was known at that time about the structure and composition of this substance. Whilst there was no evidence to suggest that the material was a health hazard, this possibility could not be dismissed, and animal experimentation has been commenced in the U.S.A.
CONCLUSIONS
Our investigations show that exposure to asbestos during brake maintenance is not as severe as was anticipated, and in the situations we examined, the personal exposurt: of the operators was below the limit corresponding to 50-year exposure.
It is however recommended that care should be C;'\crciscd during brake cleaning to a.voicl inhalation of the dust produced, and the development of cleaning procedures whirh would re~ucc air contamination is desirable. The present trend towards the
intr' be c
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FMSl 02989
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IVCd that )mpared mt there use as a
her they 1g dynarom bus nstance, 1m tem-
bi r
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remains .ing and s. The l!fferent
r, comtcrite, a edrum ; amore about -::nee to be dis-
Exposure to asbestos during brake main ten~ nee
21
introduction of "flow-line" servicing at Dealers works, in which one individual may be engaged almost entirely on brake servicing, emphasises this point.
Our environmental studies have not included maintenance procedures which involve the flling or grinding of brake lining material, and we would envisage that these would give rise to considerably increased air contamination by chrysotilc asbestos, with the attendant need for strict precautions to prevent the inhalation of ftbres.
REFERENCES
CoMMllTEE ON HYGIENE STANDARDS, BRITISH QCCUI'ATIONAL HYGIENE SOCIETY (1968) Hygiene Standards for Chry.wtile Asbestos Dust, l'crgamon Press, Oxford.
HoLMES, S. (1967) Private conununication. LYNCH, J. R. (1968) J. Air Pollut. Control Ass. 18, 824.
ancc is
~rsonal
sure. ning to :cdures rds the
FMSI 02990
r.
SUMMARY AND EVALUATION
Subject: Brief discussion of the British Asbestos Regulations as applied to brake maintenance in auto repair shops. Of interest and importance.
&valuation: This very short paper is important because the last paragraph
confirms the American study by Lynch on the small amounts of asbestos in
brake lining dust. The present author reports the results of tests per-
formed in the Industrial Hygiene Laboratory of the British Ministry of
Labour: "We have found that samples of dust from brake drums, when
subjected to X-ray diffraction analysis, contained between 1 per cent
and 3 per cent of chrysotile asbestos although the original lining
material contained more than 40 per cent of asbestos. There seems
little doubt that this is due to the considerable thermal degradation
which occurs consequent on the high temperatures generated by friction
at the
and the drum. 11
Journal: Annals of Occupational Hygiene (British), January 1970. Title: "Technical Iniplementation of the New Asbestos Regulations." Summ~: The levels of asbestos exposure for brake mechanics appear safe. However, the exposure of p:oc:_.Lcul.ar individuc...l ~Yorkers will be increased if brak'C' .~vcrhau~::; are conducted on a production line basis, making the development of adequate precautionary measures even more important. "Certainly, we should not be blowing out brake dust, even if it contains only a few per cent of asbestos."
-xxx-
FMSI 02991
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24 S. LUXON
that they indicate that the levels likely to be found in many sections of the industry
engaged in this work arc below the level of 2 fibresfcm', which is considered, in the
light of past knowledge, a safe one for chrysotilc asbestos. Their highest figures for
the time-weighted average concentration over 4 hr, however, clearly show that over a
period of 10 min we may have concentrations exceeding substantially the level of 12
fibres which are quoted above.
I was interested to hear of the increasing tendency to carry out brake overhauls on
a production line basis. This, clearly, must increase the exposure of particular in-
dividual workers, making the development of adequate precautionary measures even
more important and, in this connection, I hope the devices which will be described
later to-day can be improved and developed to the point where they become univer-
sally acceptable to the operator. Certainly we should not be blowing out brake dust,
even if it contains only a few per cent of asbestos.
In regard to this latter statement, perhaps 1 should say that work at our Industrial
Hygiene laboratory confirms the figures indicated in the previous paper. We have
found that samples of dust from brake drums, when subjected to X-ray diffraction
analysis, contained between I per cent and 3 per cent of chrysotile asbestos although
the original lining material contained more than 40 per cent asbestos. There seems
little doubt that this is due to the considerable thermal degradation which occurs
consequent on'the high temperatures generated by friction at the interface between the
lining and the drum.
REFERENCES
Asbestos Regulatio11s (1969) Statutory Instrument 1969 No. 690. COMMITTfE ON HYGIE:-IE STANDARDS, BRITISH OCCUPATIONAL HYGIENE SOC!HY (!968) lfygie11e
Stu11dards for Chrysolite Asbestos Dust, Pergamon Press, Oxford. HICKISH, D. E. and KNIGHf, K. L. (1969) Ann. Occup. Hyg., 13, 17.
A11n. Occttp. H.
POSSIB1
I HAVE been The facts a shortly he~ then I thin]
This is J
even~ually l
loss in perf\
Having~
the reasons friction mat
The first pregnated w which, while The main fu spheric oxyg resulted in II drying oil w; abrasion.
As brake degrade and In other wor
Around I that textiles c neither burn~ conditions b, 1940's when, asbestos text because the proved to be
This paper Clutch Maintcr
FMSI 02992
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'
Ann. Occup. Hyg. Vol. IJ, pp. 23-24. Pergamon Press 1970. Printed in Great Britain
January 1?70
TECHNICAL IMPLEMENTATION OF THE
NEW ASBESTOS REGULATIONS*
S. LuxoN
H.M. Factory Inspectorate, Department of Employment and Productivity, Chepstow Place, Westbourne Grove, London W.2.
THE NEW Asbestos Regulations were signed by the First Secretary of State on May 13 1969, and will therefore come into operation on May 14 1970. They are based on the concept that asbestos dust must be so controlled as to be at a level which will not be liable to cause injury to health.
For the purpo.ses of our discussion today, I believe we should take this to he a level of 2 fibrcs,'cm' and 0 I mg!m for chrysotile asbestos. A fibre is taken as being
5 p. or over in length with an aspect ratio of at least 3: I. This is of course the standard
proposed by the British Occupational Hygiene Society (1968) Bnd is based on timeweighed avcrr.ge concentrations. There is a practical limit on the time over which samples can be taken if the exercise is not to become unnecessarily cumbersome and expensive. On this basis, a sample of 4 hr duration seems a reasonable compromise. If we accept this, as a practical sampling time then the overall standard becomes 2 fibres/em over this four hour sampling period.
We cannot, however, afford to ignore ent!r;ely peak concentrations which will occur during this period, and it seems reasonable to expect that a concentration ofy say 12 ftbrcsjcm' should not be exceeded during any period of 10 min, i.e. we mig_ht regard 12 Jibresfcm as a ceiling value.
It must be remembered that we arc liSing the fibre count not as an absolute measure of concentration but rather as a conveniently measurable parameter to indicate the total asbestos in the air. The work leading to the formulation of the BOHS Standard referred to above related to conditions in the textile industry and not enough infom1ation is yet available on the relationship between mass of asbestos and tibrc counts in other indu~tries. To further complicate the problem, it is not known what ftbrc sizes are biologically active and, even if this were known, appropriate clutriation (i.e. the rejection of material not biologically active) would be very di!licult with a fibrous material such as asbesto5. We, ourselves, arc making both fibre counts and total mass determinations by X-ray diffraction analysis in industries, such as the motor industry, where degradation or the fibres may occur, resulting in a substantial change in size distribution.
HICKISll and KNIGIIT (1969) have described conditions during the servic-ing of braking systems. The figures they have quoted arc, to a large extent, reassuring in
*This p:~pcr was originally rrcscntcd at a Conference on Exposure to Asbestos during Brake and Clutch Maintenance, held al Brt:nlwood, Essex, March, 1969.
23 c
FMSI 02993
'.
'
SUMMARY AND EVALUnTION Subject: Discussion of the possible use of materials other than asbestos for auto brakes. Of interest and importance. Evaluation: The conclusion of the author is that asbestos is practically indispensable for auto brakes at the present time. If asbestos were not available, we could "eventually find a substitute, but it could well be at the expense of a considerable loss in performance, and also at a considerable increase in cost." The author also emphasizes that there is no valid health reason why asbestos should be abandoned at the present time. He cites the tests demonstrating the very small percentage of asbestos fiber in brake lining dust and concludes that "the wear products from friction materials are probably no more dangerous to health than many other dusts and can be treated as 'merely dirty."' He also mentions that technical developments have reduced the quantities of asbestos needed in the pro~f-efficient brakes and clutches, ' Author: e F e r o d o Company). Journal: Annals of Occupational Hygiene (British), January 1970. Title: "Possible Alternatives to Asbestos as a Friction Material." Summary: As given above.
-XXX-
FMSI 02994
~~'~..:~;.~;_-.~.~~l~~-:1w...;..~,~;1";;:.;.(;.,~,.~~~~,f;~~lrh:kit.r.+.-.~-~~~~~~-2.3....-lt~~fdt'e'A4~~-~..a:t..:.:.~t.'~~~ ~
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1c industry red, in the ligures for 1!lat over a level of 12
trhaill~ on ricular in:.urcs even described -11c univcri:ake dust,
!Industrial 1 We have !lifiraction 1 although .ere seems :h occurs
1
!tween the
il Hygiene
~.
.Ann. Occup. Hyg. Vol. 13, pp. 25-29. Pergamon Press 1970. Printed in Great Ilritain
January 1970
POSSIBLE ALTERNATIVES TO ASBESTOS AS A FRICTION MATERIAL*
D. HATCH
Ferodo, Chapcl-en-le-Frith, Derbyshire
INTRODUCTION
I HAVE been asked to talk on the possible alternatives to asbestos as a friction material. The facts are that if by "alternative" we mean a new or better fibre which might shortly be available as a replacement for asbestos in conventional friction materials, then l think the chances arc so remote as to be not worth considering.
This is not to say that if the world supplies of asbestos dried up we would not
eventually find a subsfitute, but it could well be at the expense of a considerable loss in performance, and also at a considerable increase in cost.
THE ROLE OF ASBESTOS IN FRICTION LININGS
Having started on what may appear to be a rather depressing note, Jet us exa1nine
the reasons why asbestos occupies the role of an almost universal constituent in
friction materials at the present time.
The first automotive friction linings were made from cotton textile material im-
pregnated with drying oils which were subsequently cured to form a strip of material
which, while b.:ing flexible and conformable, still exhibited great mechanical strength.
The-main function of the drying oil was to protect the cotton from attack by atmo-
spheric oxygen, which, even at the temperatures reached by early brakes, would have
resulted in the cotton burning had its surface been exposed. A second function of the
drying oil was to prevent the cotton from fraying under the influence of mechanical
abrasion.
As brake operating temperatures increased, it was found that cotton started to
degrade and lose its strength even though still protected from attack by oxygen.
In other words, it suffered thermal degradation instead of oxidative degradation.
Around 1910, a technological break-through was achieved when it was discovered
that textiles could be woven from asbestos and used to replace cotton, because asbestos
neither burns nor loses its strength below about 500C. However, as brake operating
conditions became steadily more severe, a point was reached in about the middle
1940's when, despite the continual improvement of synthetic resins with which the
asbestos textile was impregnated, further heat resistance W<1S required, this time
because the organic part of the composite was provmg inadequate. The solution
proved to be. to mould brake lining> f'rJm powdered resins, using short fibre unwoven
*This paper was ,>~;:;inally presented at a Conference on Exposure to Asbestos during Brake and
Clutch Maintenance, held at Brentwood, Essex, March, 1969.
25
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FMS\ 02995
...
26 D. HATCH
asbestos to maintain the necessary strength and flexibility. This made possible the inclusion of heavy loadings of mineral anti metal ti.llers which imparted greater heat resistance than coukl be obtained from resin and asbestos alone, and did so at the expense of a reduction in asbestos content. The last point is important in the context of asbestos substitutes. The question is often asked, "why can't asbestos be replaced by something like glass fibre which, after all, must surely impart sumcient strength?" The answer is possibly "it can", if merely the performance of a textile lining is required, but at the temperatures commouly met in modern brakes, the glass fibre melts even in depth below the operating surface.
aFurth~rmore, as result of the embrittling effect of mineral and other ftllers
needed in today's brake lining, glass fibre is inadequate in imparting the necessary strength and flexibility. The same can be said to a greater extent, of the various types of rock wools and mineral fibres which have appeared on the market over recent years. It is interesting to note that not 011ly is the ultimate strength of asbestos almost three times that of glass fibre, i.e. 550,000 lb/in.' but the modulus of rigidity is up to ten times as high, at a value of 30,000,000 lb/in. ' Typical figures for other materials are say 100,000 lb/in.', for steel wool and down at 60,000 lb/in.' for mineral wool.
The current situation therefore, is that in drum brake linings of normal configuration us<:d for passenger cars and commercial vehicles, there exists no substitute for asbestos >vhich would not result in a deterioration of performance and strength.
DISC DRAKE PADS
Rates of energy dissipation continue to rise and we have now passed the point where moulded drum brake linings arc adeqtwte for a large percentage of passenger cars. In this country, nearly 50 per cent of the passenger car axles are equipped with disc brakes, and for the second time in nearly half a century, there seem to be technical possibilities of reducing the asbestos wntcnt of friction materials. It is purely fortuitous that the friction materials used in elise brakes are designed to a stronger shape, that is, more or less square or circular pads of considerable thickness, supported, furthermore, by a metal plate of adequate stifl"ness. The friction material, therefore, docs not have to stand up to handling during assembly, does not have to withstand riveting, and could, from the point of view of bulk mechanical strength alone, be made without a high loading of fibrous reinforcement of any kind. There remains, however, thermal shrinkage and thermal shock, and in order to prevent the formation of tensile cracks normal to the operating surface, a percentage of asbestos fibre is still retained. Nevertheless, it cannot be said that the usc of asbestos in <.lise brake pads remains a technical necessity, and it is in this field of friction materials that some departure from resin-asbestos based composites could occur in the next few years on technical and performance grounds.
FRICTION 1\IATERIALS FOR CLUTCHES
As yet, I h.ave confined my comments to brakes, but the development of friction materials for clutches h<1s followed broadly similar lines. Tn recent years, however, we have seen the start of a growing replacement of manual clutches by automatic
transmis~
to airbor sintcred feature i~ that the 1
Clute seded at friction r of butt01 free mall
Sumr is a drift result of reduced : in auton
Then side ring subject c
The 1 perature because 1 because 1 importar white asl but inch point is t of water slow, tak products the end r asbestos, occurrin1 One wotl olivine {11 but in fa ducts. It by X-ray occasion: has been
l by very h the linin! I Whet l survives
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FMSl 02996
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.....,:..~~~~~.i:::c:.)'tn. :t~...:..!..~._.-_,J~~........:J.~.~~~~'tx. ....u..J.1b..:...i-;,.;..o;,~~~~:r~.:.;.:l.~~~~_;...,.U,N..\.~
possible the greater heat .lid so at the a the context ; be replaced 11 strength?" !! is required, c melts even
other fillers he necessary arious types over recent cstos almost dity is up to cr materials ral wool. ll configuraIbstitute for cngth.
d tl oint f passenger .1ipped with ~>~ technical purely fornger shape, supported, , therefore, ' wit!1stand 1 alone, be re remains, formation ftbre is still brake pads that some II' years on
ul f1iction . Iwwcvcr, automatic
Possible alternatives to asbestos as a friction material
27
transmissions where the clutch packs arc immersed in oil and therefore do not give rise to airborne contamination. The friction materials used are, in any case, made from sintered metals or paper based facings in which the ftbre is largely cellulose. This feature is made pos5ible by the low operating temperatures, dlle in turn, to the fact that the materials arc immersed in oil.
Clutches for heavy duty manual shift gear boxes are, in the U.S.A., being superseded at a significant rate by the spider clutch. This is a type of clutch in which the friction material, instead of being in the form of a thin annulus, consists of a number of buttons rather like disc brake pads, and these again could be made from asbestosfree material such as sinterecl metals or ccnncis (ceramic-metallic compositions).
Summarizing the situation at the present time therefore, it can be seen that there is a drift towards the usc of smaller quantities of asbestos in friction materials as a result of a number of purely performance considerations and design changes, that is, reduced amounts of asbestos in some disc brakes, and replacement by other materials in automatic transmis-sions and some dry clutches. .
OTHER FACTORS AFFECTING EXPOSURE TO ASBESTOS
There a!e, however, several other factors which enter the equation when considering the exposure to asbestos during brake and clutch maintenance, which is the subject of this meeting.
The first is that the durability of friction materials is i;1ereasing, as is the temperature at which they will opcrdte satisfactorily. I mention these facts not only because they tend to offset the ad\'crse effect of increase in vehicle miles per year, but because they affect the whole chemistry of usbestos in friction materials. The second important point is that the type of asbestos used in friction materials is chrysotile or white asbestos, and is different from blue asbestos or crocidolite, not only in colour, but in chemical composition and also in chemical clecompo>ition. The third important point is that under the influence or heat alone, chrysotilc asbestos decomposes by loss of water of crystallization at a temperature of around 600C. The process is rather slow, taking well over an hour to convert 50 per cent of the asbestos to its degradation products. These form a series of iron magnesium silicate materials known as olivine, the end member of which is forstcritc. The olivine series of minerals arc quite unlike asbestos; both physically and chemically, being non-fibrous, and in fact, widely occurring as the major part of many common rocks (basic and ultramafic igneous). One would not expect that a significant amount of asbestos would be converted to olivine during braking except under conditions of very severe duty stich as a fade test, but in fact it is exceedingly di!Tlcult to detect asbestos in friction material wear products. It has only on rare occasions been possible to detect asbestos in wear products by X-ray diffraction methods, and onr ha~ to resort to dcctron diffraction, selecting occasional individual small 1' 1, . ,; te) show its existence. This rather surprising fact has been v~,-,:.'n for se\~ral years and current theory suggests that it is accounted for by very hjgh temperatures which arc said to exist at the points of real contact between the lining and drum or disc, even at bulk temperatures as low as IOOOC.
Whether this explanation is correct or not, it remains a fact that very little asbestos survives in the wear products after brakes or clutches have been used under normal
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FMSI 02997
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28 D. HATCH
operating conditions. As the durability of brakes improves, further reductions will occur in the percentage of asbestos which survives the wear process, because each particle of asbestos is then subjected to more heat treatment. Of the approximately I per cent of asbestos remaining in wear products, a large proportion is ground down during the wear process to much Jess than the 5 [llcngth at which particles arc judged to be fibres. This is eusy to understand when one considers that under normal conditions a lining will lose about one-millionth of an inch of thickness for every 20 ft of sliding.
Over recent weeks I have had regular tests performed in which employees' private cars, and trucks from the Company fleet have been brought into the garage for brake cleaning. The drums have been removed and in a garage with no forced ventilation, all loose dust has been removed from the drums and back plates by the use of a compressed air jet. As each brake was cleaned, instantaneous atmospheric samples were rapidly taken by a hand-pump from the centre of the dust cloud. Several of the dust clouds were visibly filthy, and would, in my view, be avoided by the operator; the dust counts taken at the point of maximum dust density were as given in Table I.
I ha in fricti in the b producl other d to sugg necessit Glass fi Steel w Minera
Carbon
Sinteret and cc
TABLE I. DUST COUNTS DURING BRAKE CLEANING BY
COMPRESSED AIRJET
Test
Non-fibrous
Fibre count
Fibre count
No.
above 2 fl.
2-5 fl.
Above 5 fl.
Samples 1
2 3 4 5 6
7 lOmin average
2000+ 109 402 607 475
1513 628
181
306 11 17 21 . 37 49 35
50
5-4 2-1 25 37 5-3 82 3-2
08
The interesting points from this exercise are, firstly, the ratio of the number of particles of asbestos to the total dust particles of a similar size, showing a very small percentage of asbestos, and, secondly, the distribution of size of the fibrous element, suggesting that those particles over 5 IL mmt have been only just over.
I am not suggesting for a minute that the practice of blowing out brake drums with a compressed air line is to be recommended, merely that an intense dttst cloud of this composition is a lot less harmful tlwn one might think.
Unfortunately, at the present time, no corresponding data i~ available from clutches but one would expect the situation to be better than in brales rather than worse, because on the one hand, surface rubbing speeds arc higher, giving rise to higher point contact temperatures, and on the other hand, wear rates are very much lower resulting in an even finer subdivision in the wear products.
FMSI 02998
-~'
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uctions will ccausc each proximately ound down ;arc judged mml condi~ry 20ft of
~es' private .~for brake cntilation, c usc of a ic samples ~ral of the operator; 'l Table I.
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Possible alternatives to asbestos as a friction material
29
POSSIBLE ALTERNATIVES TO ASBESTOS
I have confined my comments to an account of changes which arc taking place in friction materials at the present time in the normal course of technical development, in the belief that, although the use of raw asbestos must be tightly controlled, the wear
products from friction mat.erials arc probably no more dangerous to health than many other dusts and can be treated as "merely dirty". If further evidence comes to hand
to suggest that a substitute for asbestos must be found, then under the pressure of necessity, a list of possible replacements could be drawn up as follows:-
Giass fibre Steel wool
Low strength-low melting point-severe frictional instability. Low availability-high cost-low strength-damage to drums.
Mineral wool
Very low strength-brittle to the extent of limiting mixing processes.
.Carbon fibres
100/lb currently forecast to fall to 1/lb in several years' time. Still ten times too expensive.
Sintered metals Probably the best possibility eventually, but cost will always be
and ceJmets
relatively high.
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FMS\ 02999
SUMMARY AND EVALUATION
Subject: Brief account of the work of the British Asbestosis Research Council in setting hygiene standards in asbestos friction products plants. Of some interest.
Evaluation: This paper runs only two pages, of which the first is devoted
to the background and organization of the ARC. A Working Group on Friction-
Materials has been conducting studies of dust exposure in factories making
brake linings. The studies are not yet complete, and there is no report
as to preliminary findings.
~
~Author:
(Mintex Company).
Journal: Annals of Occupational Hygiene (British), January 1970.
Title: "Control of the Use cf Asbestos-Containing Friction Materials."
Summary: As given above.
-XXX-
FMSI 03000
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Ann. Occup. lfyg. Vol. 13, pp. 31-32. Pcrsamon Prc.s 1970. Printed in Great Britain
CONTROL OF THE USE OF ASBESTOSCONTAINING FRICTION MATERIALS*
M .. L. BENTLEY
Mintex, Clcckheaton, Yorks
INTRODUCTION
Tms paper outlines the measures taken by the asbestos-using industry to find out the
nature and causes of asbesto~is, and the work it has carried out on environmental
control. Particular reference is made to dust created during the manufacture and sub-
sequent handling and machining operations of friction materials containing asbestos.
It is rather less than 40 years ago that the need for control of asbestos dust in large
quantities \Vas first recognised and the Government Regulations which became law
in 1933 have resulted in a considerable improvement in the health record of people
I employed in asbestos factories.
i
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In the 1950's, however, it became apparent that although the improvement had been dramatic, cases of asbestosis were occurring in people who l1ad joined the in-
I dustry since the dust control measures w.::re .introduced and it was also apparent that certain users of asbestos products, such as thermal insulation engineers or Jaggers were
J also being affected.
lI As a result of this the three leading Companies in the asbestos industry. B. B.A. Group, Cape Asbestos and Turner & Newall, decided that further investigation into
the nature and causes of asbestosis was necessa;y and they financed lllld set up the
Alibestosis Research Council with this objective. Since then the Asbestosis Research
CoJ.!ncil (ARC) has continuously sponsored research at Cambridge,' Reading and
other centres and has co-ordinated the work of its own research, medical and en-
gineering teams concerned with this problem.
Much of the increased awareness of health problems connected with asbestos
stems from these research projects and the-industry's own experts are acknowledged,
and have been consulted regularly, by Government Departments and other organisa-
tions both in this country and overseas. The ARC has drawn up some Codes of Prac-
ti:::: ,-,,, tllr ~J~nrlli.oJg of asbestos in those areas where the control of asbestos dust was
thought advisable at that time. The ARC has also played an active part in the formu-
lation of the new Asbestos Regulations which arc expected to become law in about 12
months.
Because of its considerable experience in using asbestos and asbestos products
itself and it~ concern that these products should be used without ri~k, it set up an addi-
tional committee last year with the principal object of intensifying the study of prob-
lems arising in the working environment, dealing with those areas where it had only,
0 This paper was originally presented at a Conference on Exposure to Asbestos during Brake and Clutch lvlaintcnancc, held at Brentwood, Essex, March, 196'J.
31
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32 . M. L. BENTLEY
,A,n. Occup. IIJ'K
recently become :1pparent that some control might be necessary and helping those concerned with satisfying the requirements of the new regulations.
This Committee is the Environmental Control Committee of the Asbestosis Re-
search Council and it consists of a number of working groups concentrating on the special problems of particular areas. One of these Working Groups is being devoted to the field of friction, materials, and has, as its constituent members, Small & Parkes (makers of Don materials), Ferodo and Mintex. This Gro11p, which has been formed recently, is concerned with the users of friction materials, both at its major customers -the brake, clutch and car manufacturers--and also in the replacement and service
field. Its concern has been, first of all, to establish whether or not a problem exists and,
if so, how big a problem it is. To this end dust counts have been taken both in premises where friction materials arc handled and serviced, and at customers' premises, by the three Companies principally involved. These tests have been taken by their own dust counting teams who have many years' experience in accurate dust measurement. This work is continuing and a picture is being built up of dust' counts likely to be encountered whilst carrying out typical operations during brake and clutch maintenance. Analysis of the dust found in brake drums is being carried out also to determine whether all the fibrous dust is asbestos or not.
In addition to gathering and collating information. on a large number of dust readings in various types of service premises, the Working Group is preparing two codes of practice for users of asbestos-based friction materials which will be
I issued by the Asbe~tosi:, Research Co'.mcil. One of these is for the guidance of bulk
users in factory premises carrying out, in some cases, operations similar to those
1 carried out in our own factories, such as cl rifling and grinding, and the other is for tile guidance of those engaged in servicing of brakcs and clutches.
1 The purpose of these Codes of Practice or Notes for Guidance will be to remind users of the principal requirements of the new Asbestos Regulations to recommend the action that they should take to meet their requirements. The aim is to achieve what is, after ~all, the whole purpose of the Asbestos Regulations and the Asbestosis Research Cquncil's work-to reduce concentrations of asbestos dust to a safe level. The long experience of the manufacturers of friction materials in dust control over a wide variety of operations will enable them to recommend- measures and types of equipment to help the users to com1,Jy with the Regulations and protect the health of their employees. "'- ~urt!;c:- line of study is being followed to sec whether a satisfactory surfacescaling agent canl::e found in OIcler to cut down the amount of dust given otT in handling a new lining, even thot:z,h this amount is already small. It is not possible for us to take J;tsl cn11nts in every service garage in the country and the work of the Friction Materials Group has been directed to dealing with, and giving advice on, situations which are likely to be typical of those found in service garages. lt is, however, the intention to give as much llefp and advice as possible with the facilities that arc available and requests for help or advice directed t8 the Asbestosis Research Council will be passed on to thc Working Group for action.
RE!
WHATEVER t
deny that th the total tim an operatior be judged ttl in using the veloping a t time require concede fror inevitable.
When vit pressed-air li sation alone objective me mental cond fibre count~) evaluate dus considerable simple methc dusts are re1~ with the con method is a 1 is important.
METHC
When du~ the clouds u Tyndall Bea1i work.
This paper Clutch Main!cr
FMSl 03002
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. ~t. SUMMARY AND EVALUATiON
Subject: Comparative study of methods used for cleaning auto brakes during servicing. Of some interest.
Evaluation: In British auto repair shops it has apparent~y be common practice to clean the dust from brake assemblies by blowing it out with a compressed air hose. The natural assumption that this process releases most dust into the air was confirmed by comparative tests using a vacuum cleaner, two types of brushes and rag wiping. However, it is noteworthy that the dust concentrations, measured by sampling devices, included relatively few fibers, which would presumably be asbestos. The author comments: "The results of fibre counts showed. that the numbers of fibres present in the high total dust concentrations obtained when an air line was used were of a low order of magnitude and hence the total dust concentration was used as a relative method to describe the dustiness of the environment."
~~-~
..--c'-_______/Author: Lee, G. L. (British Leyland Company)
Journal: Arinals of Occupational Hygiene (British), January 1970.
Title: "Removing Dusts from Brake Assemblies During Vehicle Servicing -Alternative Cleaning Methods."
Summary: "Vacuum cleaning provides a useful contribution towards obtaining satisfactory dust control when brake assemblies are cleaned."
-XXX-
FMSI 03003
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!ping those
10:s!osis Reting on the ng devoted 1& Parkes :en formed customers .nd service
:xists and,
1 premises ;es, by the own dust surcment. to be enntenancc. letermine
of dust ring two will be :of bulk to tfl.-.~e s fo ~
remind mmend
vewh~t
lSis Re-
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over a ,pes of health
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1untry
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ervice r with stosis
;
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I Ann. OcC'up. ll)g. VoL 13. pp. 3.1-36, Pcrsamon Press J970. Printed in Great Daitain
I I REMOVING DUSTS FROM BRAKE ASSEMBLIES
DURING VEHICLE SERVICINGALTERNATIVE CLEANING METHODS*
G. L. LEE
British Leyland, Longbridgc, Birmingham
PRELIMINARY CONSIDERATIONS
WHATEVER the criticisms may be from an occupational health point of view, few would deny that the operation of removing brake dusts with an air line is efficient in that the total time to perform the task is extremely short. The time required to perform an operation is of vital import:~nce in industry and any process changes will always be judged relative to the time sc~Je. In addition, the effort required from an operative in using the m~thod should be minimal and it is easy to sec that the chances of developing a technique of clcm~ing which \\ill reduce dust emi;sions but at the same time require no more tim-e and cfrort are extremely slim. Quite clearly, we must concede from the very b:;:ginning that some increase in time and effort involved is inevitable.
When viewed under nom1al lighting conditions, the result of applying a compressed-air line to remove brake dusts is very dramatic. Unfortunately, mere dramatisation alone is not adequate io describe the emission 0f dust from a process; more objective methods are needed. The conventional' method uf e\'aluating an environmental condition is the measurement of the appropriak par<Jmeter (in this case.fibre counts), referring the results to hygiene standards. In experimental work to evaluate dust control methods, simpler, "relative" techniques of measurement have considerable advantages and part of this work is concerned with applying a fairly simple method to define certain environrnental conditions which prevail when brake dusts arc removed by blov:ing out with a compressed air line and comparing these with the conditions obt~incd when a dust control technique is ~pplied. Because the method i5 a relative one, care to prevent errors from extraneous sources of variation is important. These sources of error are discusst:d later.
METHODS USED TO EXAMINE ENVIRONMENTAL CONDITIONS
When dusts are released in relatively small qu~ntitics it is often imj)ossihle to sec the clouds tmcler normal lighting conditions. They can be made visible ming the Tyndall Beam e!Tccl and this has been employed extensively during the experimental work.
This paper was originally presented at a Conference on Fxposurc to Asbestos during Drake and Clutch Maintenance, held a! Brentwood, Essex, March, 1969.
33
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34 G. L. LEE
Mass concentrations of airborne brake dusts were determined at two positions by sampling through tared membrane ftlters. In the first position, a static sampler was placed close to the sources of dust emission. Generally, this sampling position was chosen to be in the area where the results of Tyndall Beam examinations had indicated that the highest dust concentrations were likely to be obtained. Secondly, a personal air sampling device wa~ worn by the operative in such a manner that t11e sampling head was attached to the wearer's lapci, as ncar as practicable to the breathing zone.
Samples for particle counting were taken, again in the operative's breathing zone, using a Konimeter, and membrane filter samples were also taken for subsequent fibre counts by microscopy, using the method described by AoDINGLEY (1966). Possible weighing errors due to static charges on membrane filters were prevented by weighing in a field of ionising radiation, as described by HIGG!t--:S and DEWELL.
The results of fibre counts showed that the numbers of fibres present in the high total dust concentrations obtained when an air line was used were of a low order of magnitude and hence the total dust concentration was used as a relative method to describe the dustiness of the environment.
The location selected for the experiments was in a workshop area, behind a glazed partition, and well away from access doors, so that comparisons of cleaning methods were not af:fected by variations in local air movement. Smoke tests were carried out at each sampie period to confirm this point.
CONDITIONS OBTAINED WHEN A COMPRESSED AIR LINE WAS USED TO REMOVE BRAKE DUSTS
A commercial vehicle brake assembly, after removal of the brake drum rrcparatory to cleaning, is shown in Fig. 1. In this particular case, the hub had also been removed for bearing replacement which facilitated cleaning operations. It should be noted that this is not always so and for the majority o'r our tests the inconYenience of the hub being present had to be contended with.
A series of Konimeter samples were taken during typical operations and also after the process had ceased. The counts for these samples are summarized in Table I.
TABLE J. RrSULTS OF KON!MHER SA~II;LES DURING BLOW-OFF
Sample
Number of brake dust particlcs/5 em'
Taken at beginning of operation Taken approx. 20 sec later Taken approx. 60 sec later
Taken approx. 30 sec later _Tak~n approx. 30 sec later
5000 4500 4000
1800 580
It is seen that there is a progressive fall in count as the local dust cloud disperses. The first three figures arc approximate only, the numbers of particles collcctecl being too high for accurate counting.
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tin the high low order of e method to
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1s and also in Table I.
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Removing dusts from brake assemblies during vehicle servicing
35
A fixed sampling period of some 5 min was chosen for the determination of mass concentrations-this being longer than required for the blowing operation but sufficient to cover that required for the alternative cleaning methods. The dust collected by the static sampler close to the brake assembly gave an equivalent concentration of 114 mg/m' and that for the personal air sampler 42 mg/m'. It is probable that many of the particles included were larger than respirable size. The few asbestos fibres counted on membrane filter samples gave a concentration of the order 3-5 fibres/em.
ALTERNATIVE CLEANING METHODS
Initial approaches were to try the use of fL-xed and hand~held extractors to collect the dust particles removed by hand-brushing with a small paint bmsh. Fixed extractors, although reasonably efficient, were rejected because of restrictions which these placed upon the work by conlining it to one area. Doth operatives and supervision were unhappy about being confined to one work area-preferring to retain flexibility and carry out the work as they had previously done, wherever the vehicle happ'ened to be. Portable extraction equipment was clearly required and after some preliminary enquiries, a BVC industrial vacuum cleaner was selected for use in
experimental work. It is of fairly conventional type, powered by a 1h.p. motor and
supplied with disposable paper bags in addition to the normal cloth bag. The paper bags are fitted in a manner which allows them to be scaled fairly easily before removal. To trap any particulates which might pass through the paper and cloth bags, an external, multi-layer filter was provided for fitting to ihc air outlet end of the cleaner.Preliminary experiments established that some brake dust particles were passing the paper and cloth bags but these were trapped by the externally fitted filter. Sampling at the exit side of the filter established that no particles passed the filter.
"'- -
CONDITIONS OBTAINED USING THE VACUUM CLEANER AS A SOURCE OF EXTRACTION
The ftrst technique tried was to use the nozzle of the cleaner, hand-held as a source of local extraction whilst the dust deposits were disturbed with a small paint bmsh held in the other hand. The Tyndall Beam showed that some dust was escaping into the environment. Objective measurements arc summarized in Table 2.
TABLE 2. RESULTS OF KONIMETER SAMPLES DURING IIRUSIIING AND
W!Tll LOCAL EXTRACTION
Sample
Number of brake dust particlcs/5 em'
Taken at start of process Taken about 1 min later Taken about 2 min later Taken at' end of pr,ocess
1070 404 426 446
FMSt 03007
... -1
36 G. L. LEI!
The fixed sampler in the area of the highest concentration gave a dust concentration of 21 mg;'m' and the personal sampler, 27 mg/m'.
An improvement in controlling the release of dust had been obtained but was not considered compktcly satisfactory and an alternative approach was sought.
CONDITIONS OBTAINED USING A MODIFIED TECHNIQUE
After some preliminary experiments, the following general technique was devised. Firstly, the loose ueposits of dusts inside the brake drum and on readily accessible surfaces of brake shoes and the brake assembly were removed, using the smallest brush supplied with the cleaner--the equipment being used as a vacuum cleaner. A mlJCh narrower, tubular brush, made from available materials was then used to remove deposits from less accessible surfaces. Finally, a rag, soaked in water and wrung fairly dry, was used to remove adherent deposits. No visible emissions of dust were observetl but a few particles were detected by the objective methods, as shown in Table 3.
TABLE 3. RESULTS OF KONIMETER SAMPLES DURING MODIFIED TECHl'ilQUE
Sample
Brushing wilh standard brush Brushing with wbular brush Rag wiping
Number of brake dust particlcs/5 em'
16-25 20-25
l-5
No fibres were detected and the mass concentrations involved were too low to
det~rmine.
CONCLUSIONS
The objective measurements made seem to confirm that vacuum cleaning provides a useful contribution towards obtaining satisfactory. dust control when brake assemblies are cleaned. The design of the particular cleaner chosen prevents the discharge of particles back into the environment and the collection in a paper bag enables suitable disposal methods to be adopted. This work \Vas completed in the early part of 1968 and subsequently the method described was recommended for use until such time as the results of studies being carried out elsewhere in the lVfotor Industry were known and detailed requirements subsequently formulated.
Acknowlcdgemems-The assistance of Mr D. Smith of the Industrial Hygiene Department and Mr Young, Works Engineers, is gratefully acknowledged.
REFERENCES
ADOINGLEY, C. G. (t966), Ann. occup. !lyg. 9, 73. HtGGINS, R.I. and DEWELL, P. in Instruction Leaflet 3107/Al, C. F. Casella.
T1 as
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dust concentraned but was not ought.
NJQUE 1ue was devised. ~adily accessible ing the smallest acuum cleaner.
as then used to :d in water and missions of dust )ds. as shown in
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rere too low to
~aning provides n brake assemlS the discharge ;nahles suitable Jy part of 1968 til such time as ry were kno\vn
rtmcnt and Mr
January 1970Ann. Occlfp. 1/yg. Vol. 13. pp. 37-39. Pergamon Press 1970. Printed in Great Britain _
INVESTIGATIONS INTO ALTERNATIVE FORMS OF CONTROL FOR DUST GENERATED DURING THE CLEANING OF BRAKE ASSEMBLIES AND
DRUMS*
K. L. KNIGHT and D. E. HICKISH
Medical Services, Ford of Briiain, Brentwood, Essex
INTRODUCTION
THE Mosr usual method of removing the accumulated dust from brake drums and assemblies is by "blowing off" with a compressed air stream. This, of course, generates a dust cloud in which the operator works, proportional.:: in size to the drum,'assembly being cleaned. We therefore iiwestigatccl two alternative methods of conlrolling dust generated at a maintenance operation on commercial vehicles, l!S representing maximum likely exposure.
Enquiries at the beginning of the investigation indicated that the removal of dust is to allow inspection of the mechanism, rather than being a 1naintenance procedure in itself. Om efforts were, therefore, directed towards the removal of loose dust from the parts of the brake mechanism which needed inspection, rather than achieving total cleanliness.
The criteria for evaluating the two methods devised were firstly, that the alternative method did not take significantly longer than the method already in use, secondly, that it was not more difllcult to ca~ry out, and thirdly, that very little extra equipment was i1eeded.
ALTERNATIVE METHODS EXAMINED
The alternative methods examined were a vacuum funnel, and a vacuum brush.
Vacuum funnel The funnel (sec Fig. 1) comprised a steel cone with a connection point at its apex
for an industrial vacuum cleaner; a flexible skirt, with a draw string attached at its periphery; and a small-bore side-entry for the injection of compressed air. In usc, the funnel was secured over the backplate of the brake assembly or over the drum and compres,ed air was injected to dislodge dust while the vacuum cleaner extracted dust-laden air. The assembly \l'<tS rotated around the total circumference to complete the cleaning operation.
*This paper was origin31ly presented at a Conference on Exposure fo Asbestos during Brake and Clutch Maintenance, held at Brentwood, Essex, March, 1969.
37
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38 K. L. KNIGHT ami D. E. HICKISH
Vacuum brush The vacuum brush shown in Fig. 2 consisted of a circular nylon bristle brush
mounted on an angled handle and fitted via the handle to the same vacuum cleaner. In use, the brush was used to remove dust from drums and assemblies under vacuum.
EXPERIMENTAL PROCEDURE
In order to determine which of these two methods was the better, the performance of each was compared with the traditional blow-off method, in two separate experiments shown in Table I.
TADLE. 1. EFFECT OF CLEANING METHODS ON DUST CONCENTRATIONS
Hour Activity
1 Background
2 Blow-off
5 Background
66 Funnel Brush cleaning cleaning
Personal sampler Static sampler Peak sample
particlesfcm3 fibres/em particles/em fibres/em' particles/em fibres/em'
116 422 096 5-35 161 12 045 052
41750 87
107 095
162 041
415 35 210 075 759 104
Personal sampler Static sampler Peak sample
particles/em' fibresfem3 particles/em
fibres/em particles/em fibres/em
125 635 016 084 129 155 010 016
41750 87
140 009
110 020
158 022 122 018 310 057
."
During the first hour of the day air samples were collected to determine background com:cntrations; during this period the near side front road wheel was removed. In the second hour samples were collected during dust removal from the near side brake assembly by blow-off. Further background samples were taken during the fifth hour while the off side front road wheel was removed; and during the sixth hour dust determinations were made while either the funnel or the brush cleaning methods were
USI"'rl
{ The personal samples were collected from the. breathing zones of mechanics engaged in the work and static sample5 were collected concurrently to simulate exposure
I of mechanics working in an adjacent repair bay. Short duration samples were also
collected by means of a Drager pump from the operator's breathing zone at the peak
period of dust generation.
.
l All the samples were subsequently analysed for fibres in accordance with the kd::~ique iaid down in the Hygiene Stam/ardfor Cf,rysori/e Ash:~stos published by the British Occupational Hygiene Society ( 1968). Particle CO!Jnts were limited to particles greater than 1 [L dia.
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Alternative forms of control for dust generated <luring the cleaning of brake assemblies 39
DlSClJSSlON
The results for the vacuum funnel rs. blow-off experiment and for the vacuum brush versus blow-off arc shown in Table I. It can be seen that the background concentrations during the ftflh hour had re-established at the original level after a 2 hr latent period and therefore the blow-on operation carried out during the second hm1t did not afTcct the concentrations observed in the vacmun funnel samples collected in the sixth hour. The funnel appears to reduce personal exposure by 2 per cent for particles and 40 per cent for fibres; concentrations observed in the adjacent bay are increased and a reductio:1 in peak concentrations of about 80: I was achieved.
During the second experiml~nt there was more variability in the background concentrations between the first and firth hours but the effect of blow-off on the vacuum brush test may be discounted. Perso)lal cxpos'ure by use of the brush is reduced by 75 per cent for both particles and fibres and the static samples show a reduction of 20 per cent for particles but an increase of 12 per cent for fibres. A redlJCtion of 80:1 in peak concentrations was again observed.
CONCLUSION
The experiments dem01istrated that the vacuum brush was better in reducing operator's exposure; it had the added advantages over the funnel of being easier to handle, con':istcd of fewer, simpler parts and was much quicker than the vacuum funnel.
There are three major reasons for the relative incnlcicncy of the funnel; its use increased brake cleaning time (and thus exposure time) by a factor of 8, it was difficult to obtain a good seal at the skirt, and imbalance occurred between the necessary air input and the capacity of the available exhaust system, with resulting leakage of dust.
REFERENCE
COMMIITEE ON HYGI!'NE STANDARDS, BRITISH OCCUPATIONAL HYGIENE SOCIETY (1968) Hygiene Standards for Chrysotife Asbestos Dust. Pergamon Press, Oxford.
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SUMMARY AND EVALUATION Subject: Discussion of the preferred type of vacuum cleaner to use in cleaning auto brakes during servicing. Of some interest. Evaluation: Having determined that blowing the dust out of brake assemblies with a compressed air hose releases the most dust into the air, the authors investigated the use of vacuum cleaning equipment with two types of pick-up heads. It was determined that a brush on the end of the vacuum hose is more efficient than a funnel attachment.
Journal: Annals of Occupational Hygiene (British), January 1970. Title: "Investigations into Alternate Forms of Control. for Dust Generated During the Cleaning of Brake Assemblies and Drums." Summary: As given above.
-XXX-
FMSI 03012
Jeremiah R. Lynch
Notional Center for Urban and Industrial fleolth
Brake Lining Decomposition Products
A number of investigators have found asbestos bodies in the lungs of urban residents who were not oc cupationally exposed to asbestos. A relationship between the carinogenic properties of asbestos and the urban excess of lung cancer has been suggested. The decomposition products of brake linings have been described as a possible source of these fibers. Broke testing laboratory methods were used to test flber emission from a variety of friction products. Only a very small fraction of the asbestos escaped as free
flber while the remainder was transformed into some other, nonfibrous, mineral. A significant release of free
flber occurred only under conditions extreme enough to produce broke failure.
Table 1. Asbestos bodies in human lungs.
Location
Year
%
Positive
Cape Town (2) Miami (2) Pittsburgh (3) Johannesburg (4) Finland (5) Montreal (6) San Francisco (1)
1963 26 1965 27 1965 41 1965 39 1966 58 1966 48 1966 42
Table 11. Brake lining composition.
Ingredient
Automobile Truck
Asbestos
Resins and polymers
Oxides and pigments
Metals
Carbon, graphite, etc.
55
28
9 3
5 100%
33
48
16
2
1
fOo%
~[r. L\'llch i' ChiPf of tht> L:rhoro.tory -of Engineerinl(. t npational Health Pro.:ram, l't~llir: Health ~ervie!', I lepart nwt11 of Health, Ednf'alion, and \\"elfan, 1014 Broadway, Cilll'innat i, t thio 4.-,202.
824
The occurrence of coated fibers referred to as "asbestos bodies'' in the lungs of urban populations not occupationally exposed to ashe~tos has been noted by sevl'ral inwstigators. The results of several autop..;y ,.;erie..;, as summarized by Cooper,' are shown in Table 1.1 _, Thompson,' in ,.;nggesting possible modes of exposure that ('Ould account for the:'e bodies, stated:
The average private motor vehicle wears out three or four 'et>< of brake linings and one or two clutch linings in it." lifetime. and commercial and public tran-port vehirles wear out n1an~ more. The:->e linilll!"' con~i~t. largely of a'best-o,o which is gro\ntd ttl Ju><t as the linings weat, and mo,ot wear CJ('<'\lr' in huilt-np areas. This alone in mn f'ities would involn' the di,-rhargr of many tJIIS of a.c;be~to., dn~t anl fiber,- in the .,treets each y!'ar.
Since asbestos has lwen implicated as a carcinogen' and lnng; !'ancer has a higher incidence' arnnnp; nrhan pnpulations, the fate of the a:;bl>t<h wom irom brake lining" become:< ,-ig-nificant.
Brake lining Composition
The a\erage cornpo~ition of t~pieal brake linings of the type k<trrl is 'hown in Table II. Indi\idual rni~e,; rna\ \an' considerably from the..;e average,. .
Each of these ingredient.- performs a particular function. The a,bcsto..; provides strength, heat re:;istancr, and ,oeleetive deeomposition undrr -trc.-;s. The rpsins and polymer.-; hold thl' otlwr ingrcdietlh together. \"arioth O'\irJr, are addl'd a,; pigments and to impro\e the grip of the lining; on the drum. Soft metals ~ueh us ]pad and bra's improve wear while carbon and graphite serve
as friction modifier~. Brake lining quality depends to a lar~e
extent on the type of binder u,;ed. Linseed oil. which begin~ to decompo,;e at about 450F. is used for light senice brakes. :\fore demanding ~ervice requires brakes made from !'ashew type resin~ or oil modified phenolie re~ins. These ingredients are mixed, either dry or with a sohent added. formed into shape, and cund in au oven. The hardened lining is then cut, ground, and "andecl to the preci,;e dimen,ions of the finisheJ linings. The dwc;t pnduced by the abrading operation~ in asbe-;tos friction prodnet factories (Fi.(!;ure 1} contains free asbestos fibers that ate ~imilar to t.ho:;e in industries where cancer is known to be' in exce,;:;.'" The question to he re:;ohed, therefore. is whether the dw;t produeed b\ the normal wear of brake linings contains this same type of free asbestos fiber.
Test Methods
In an initial exploratory .~urvPy, the dust obtained from inside automobile brake drums removed for brake relining was examiner! by electron micrograph. Figure 2, which i' typical of the '"riP,;, does not reveal any free fiber,. Ho\\"ewr, this finding did not eliminate the possibility that free asbe,-tos fiber.' \\ere relea,ed and that they had e,rapr><l into the at.nHl:iphere. To examine this hypothe,;is a o<rries of e~pcrimPnh wa~ ue\i,cd to permit ~ampling dt(ontpo,;ition products of the lining undPr :"imulatcd Op(rat ing ('OtHlition,. The tl'.'h (Table Ill) were performed with the brake testing maehines in the laiJilrtttor~ oi a ntajor brake lining manufacturer. :\lost of the tests were performed on a
Journal of the Air Pollution Control Assod,.tinn
FMSI 03013
Table Ill. Test results by electron micrograph.
Test Product Brand Method
Presence
No. of Conditions of Free %Free
Samples of TestF
Fibers Fiber"
1. Automobile A Friction
6 300.800 Few <1
drum
brakes
2. Automobile B Friction
6 250 800
None
0
drum
brakes
c3. Automobile
Friction
5 300 700 Few <1
drum
brakes
4. Automobile c Friction
700-900 Numerous ~10
drum
brakes
5. Automobile D Friction
5 300.800 Few <1
drum
French
brakes
6. Automobile E Friction
300-700 Few <1
drum
brakes
7. Automobile F Friction
5 300-800 Few <1
drum
German
brakes
8. Automobile G Friction
2 100.500 Few <1
drum
brakes
9. Automobile G Friction
1 600-700 Numerous ~15
drum
brakes
10. Automobile H Friction
2 100-600 Few <1
drum
brakes
11. Automobile
clutch
Dynamometer
Normal driving
None
0
12. Automobile K Dynamometer disk
Normal driving
Few
<5
brake
13.
Bus drum
L
Dynamometer
brake
City driving
None
0
14.
Bus drum
M
Friction
2 450.550
None
0
brake
15. Truck drum F Friction
10 300.800 Few <1
brake
(light)
Weight estimated from fiber volume.
Some independent expt'rinwut.' rlone at a brake lining re~eareh laboratory" have shown that all of the mal.(nl',ium present in the chrysotile a~he"t"" originally in the lining ean he aee<JIIIlt<'d for in the decompmition product~. However, the characteristic X-ray diffraetion pattern of chrysotile aobe,to~ had vanished. Thw<, it is apparPnt that under conditions in whieh a~be~to" i~ worn from the lining of a brake, the asbestos is destroyed.
Conclusion
Only a very small proportion of the asbestos worn from brake linirq.!> i" released as free fiber; the remainder is converted into some other mimral as a re~ult of the extreme temperat url's genPratrd at small spots on the lining 'urface. Thus, although urban air ,ontains a few free fiber~ as a result of brake lining wear, they represent a \'Cr~ ~mall
826
proportion of the total asbestos u:;ed in
manufacture of brake,;. :\Iany sourct's
of respirable fibers not associated
with a;;bestos products have been idt'nti-
fied," and free fibers from brake lining
wear seem to be an inconsequential
health factor in urban air pollution.
References
1. Conper, V.'. C., "Asbestos as a hazard to health," Arch. of Env. Health. 15: 28:i (1961).
2. Thomson, J. U., Kaschula. R. 0. C., and McDonald, R H., "Asbe,tosi:; as a modern urban hazard," S .. lfr. .\Jed. J. 37:77 (l!lo:{).
3. Catma, D., Totten, IL S., and (;ross, P., "A-;bestos bodies in human hlllh"' at autops~," .J..t.llA, 192: :17 II!}(;.)).
4. \Vebst.er, I., in rli>'cussion of Thomp-;on, :-3. F., ''-Phy:-:io!o~i<"al l'ffeet of ])20 in marnmab," ,[nn. X. L Acad. Sci., 84: 7:)6 ( 19li0 ).
.). ::\Ieurman, L., ".\,lw~tos bodi(s and pleural plaques in a Finish ,pries of autopsy ,.,cses," Adn Path .\I icrobiol. Scand Suppl., 181: 101 (l!Hifl).
6. Ar.vilrel, L and Thurlbe~k, W., "The incidence of a..sbestos bodies in the lungs of randon autopsies in Montreal, Canada. Mer!. Assoc. J., 95: lli!l (1966).
'. Thomson, J. U., 'rubesto,; and themban dweller,'' Ann. N. V. Acari. Sci., 132: l!lfi ( I\Jt\.5 ).
8. SelikofT, I. J., Churg, J., and Hammond, E. C., "Asbestos exposure and neoplasia," JAMA, 188: 22 (J!l6-!).
!l. Buell, P. and Dunn, J. E., "Helative impact of ~moking and air pollution on lung cnneer," Arch. of Env. llealth, 15:291 (1!!67).
10. Enterline, P. E. and Kendriek, :\1. A., "Asbestos dtL~t exposure,; nt various levels and mortality," A. rch. Enu. Health, 15: lSI ( 1967).
II. Rinclair, D., "Study of wear <lu,;t, from hmke lining," .Johns-:Vfanville ({,.,and Eng Ctr., personal communiet! ion (1!.)67).
12. Crallcy, L. J., Keenan, IL G .. L\'ndt, J. IL, :wd Lainhart, \'1'. S., "~otl\'<'t' and identification of re,;pirahle llhers," Amer. Ind. Ilyg. A~soc. J., 29: 12\.l (196S).
Journal of the Air Pollution Control Association
FMSI 03014
BRAKl LINING DECOMPOSITION PRODUCTS
In recent years, some individuals have pointed at brake lining wear as a probable source of asbestos contamination of the ambient air. In this paper, Jeremiah R. Lynch of 'the National Center for Urban and Industrial Health, HID~, refutes this theory by showing that in all but a few extremely severe automobile braking tests, less than one percent asbestos fiber could be found in the collected dust. He concludes that hrake lining wear is "an inconsequential health factor in urban air pollution."
...
FMSI 03015
.-..;.;;,.......=::.__-~ .. ~
PB 192 252 NATIONAL INVENTORY OF SOURCES AND EMISSIONS: CADMIUM, NICKEL, AND ASBESTOS - 1968. ASBESTOS, SECTION III David (W. E.) artd Associates Leawood, Kansas February 1970
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FOR FEDERAL SCiENTIFIC AND TfCHNiCALINFORMATIO~
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This ducument has been approHd for public release and sale.
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ASBESTOS lMPORJ;Jf'"""
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- -. . . .7 .-. :;During 1968, asbestos imports wg& 737,909 short tons. Approx-
lm~otalimately S4 percent of the
was from Canada and 5 percent
/ ASBESTOS EXPORl'S
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s, durin9 1968, were 41,236 short tons.:;
- Bureau of Mines Minerals Yearbook - 1968
-7-
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REPROCESSING
'~. '.
Tbe apparent consumption of asbestos in the United States, durin9
1968, has been reported at 817,363 short tons,~/
FRICTION MATERIALS Asbestos is regarded as indispensable in most types of friction materials. It is used es the primary constituent in brake linlnqs and clutch facings for motor vehicles, and other commercial and industrial equipment,
Br:ake linings are of two principal types. In the early days of the automobile, virtually all brakebands were of woven asbestos fabrics but now the molded type is uaed extensively, Molded linings consist of esbestos fibers bonded with an organic matriX. Metallic reinforcing "is commonly added, and the shaped products are thoroughly cured. Chrysotile asbestos is required, rengiriQ.ln fiber length from the very short grades to those J<1St under spinning grades.
In the United Stetes the use of asbestos 11'1 friction materials during
1968 was about 104,000 short tons.~/ Reprocessing plants producll\9
friction materials are listed in Appendix A.
1- Bureau of Mines Minerals Yearbook - 1968 2- Estimate based on reports from reprocessing companies and data
from the 1967 Oenaus of Manufacturers.
'~ ~
-19-
REPROCESSING
An outstanding characteristic of the asbestos industry is that a very large propo:-tion of the fiber is mined, imported, processed, and reprocessed by a relatively few companies, Very 1ittle <>f the finished product is sold to the consumer trade.
The original use of asbestos was based on its heat resistance properties, but the current use is more often as a blnder. such as in asbestos cement products.
The asbestos fibers are usually sold in 100 pound bags which are paper bags or Jute bags which sometimes have a plastic liner. The disposal of these bags seems to present a problem to the industry, A few are able to use the paper bags in the product being produced, but many more are still seeking a satisfactory solution.
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creates a substantial loss of asbestos, as much as thirty percent. With such a grinding procedure an adequate exhaust and collection system is essential.
A large manufacturer of brake linings reported 4000 tons of asbestos collected in bag filters at one plant during 19 68 and described his collection system. He estimated overall atmospheric emissions of asbestos to be 0.25 to 0,50 percent, based on the efficiency of his collection equipment. Other manufacturers provided some information regarding the type of collection equipment in operation, but not data or estimate_s of asbestos emissions.
On the basis of information obtained an emissions factor of 6 pounds per ton of asbestos processed is estimated, and asbestos emissions to the atmosphere during 1968 are 312 short tons.
FRIC!ION MATERIALS
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One of the largest uses of the frictic>n material is ill brake linings of the molded type. The molded linings, consisting of asbestos fibers bonded With an organic matrix, oontain approximately fifty percent asbestos, As a part of the manufacturing process, the linings must be shaped and finished by grinding after they are formed, This
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fiber, were sold to a contractor durlng 19 68 for use on roads. It is reported that an appreciable amount is used in Vermont for
roads. _1 I This could not be confirmed, si.1r.e permission to
visi the mine and mill was denied.
Construction
Workmen in all trades in the construction industry come in contact with asbestos. Heating duCts are often insulated with asbestos, and steam piping is nearly always covered with a material containing asbestos. Electricians strip asbestos insulation from wires, and the carpenter saws asbestos siding, wallboard, and shingles. As a result, there is asbestos released to the air around the con-; struction sites.
Asbestos emissions to the atmosphere at construction sites are estimated at 61 short tons for 1968.
'Brake LininM
Motor vehicle travel during 1968 totaled one trillion inUes, and replacement brake linings were required for about 25 to 30 million vehicles. It is the usual practice, when installing new brake linings,
1- May-Timothy C.; Asbestos; Mineral Facts and Problems; Bureau of Mines Bulletin 630 - 1965
I
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-30-
to fit the linings to the drums by grinding, and the amount of grinding required varies depending on the condition of the brake drum.
Data concerning motor vehicle brake linings:
Vehicle miles during 19 68
1,010,000,000,000
Mileage life of brake linings
27,500
Brake lining sets on new vehicles
10,718,000
Pounds of asbestos per set of brake linings
3
Assumed loss to atmosphere during grinding
and fitting - percent
0.5
Based on the above, the emissions factor is 10 pounds per ton of asbestos processed, and the asbestos emissions to the atmosphere during 19 68 were 190 tons.
Steel Fireproofing Several spray-on materials that contain asbestos are used extensively on steel columns and other structures as a fire pro- tectlon measure. The application <"'f such.materials is often required by code. Even though the buildmg frame may be covered by a temporary enclosure when the material is sprayed, the workmen are exposed to an atmosphere that is virtJally saturated with asbestos fiber,
Asbestos emissions to the atmosphere, due to the use of spreyon fireproofing during 1968, are estimated at lS short tons,
-31-
based on an emissions !actor o! 10 pounds per ton o! asbestos applied.
Motor Vehicle Use
It is obvious that there are q1.bstantlal particulate emissions from the wear of motor vehicle brake linings and clutch facings. This has. been reported as a primary source of asbestos emissions to the atmosphere; however, there are conflicting rePOrtS indicating that the asbestos fiber has been destroyed by the heat of friction.
In this rePOrt the estimate of emissions does not Include an amount for the wear of motor vehicle brake linings and clutch facings.
Insulating Cement
Insulating cement that contains asbestos Is used extensively in all types of boilers. It Is used for pointing up joints and cracks in stack and breaching linings, and for surfacing block insulation that is ins\alled i'lside breechings, ducts and liCC.omizers. During the boiler operation, as the flue gas passes through the boiler some of fhe insulating cement is worn away and carried along through the dust collector, up the stack, and into the atmosphere.
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I pounds per ton of asbestos applied is calculated for the use of
I insulating cement. I 1 - Fifteen percent of the Insulating cement worn away during
use,
I 2 - Oust collector efficiency - 89 percent (average)
Asbestos emissions to the atmosphere during 1968 due to the
use of lnsuiating cement are estimated at 25 short tons.
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-34-
ASBESTOS MINES IN THE UNITED STATES
I
ARJ?.ONA
LOCATION
I Asbestos Manufacturing Company
Gila. County
Jaquays Mining Corporation
Gila County
I /Metate Asbestos Corporation
.Gi.la County
/
CALIFORNIA
/
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Atlas Minerals Corporation Coalinga Asbestos Company (1) Pacific Asbestos Corporation (2) Union Carbide Corporation
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Fresno County Fresno County Calaveras County San Benito County
NORTH CAROUNA
I
! IPowhatan Mining Comp;iny
Yancey County
VERMONT
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GAF Corpora/n
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Orleans County
(l) - /wned by Johns-Manville Corporation
H~(2(-Acquired by K, Porter Company, Inc. during 1968.
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REPROCESSING PLANTS PRODUCING ASBESTOS FRICTION MATERIALS
QAIJFORNIA
H. Krasne Manufacturing Company Silver Line Brake Lining Corporation Lasco Brake Products Corporation, Ltd.
LOCATION
Los Angeles Los Angeles Oakland
CONNECTICUT
H. K. Porter Company, Inc. Raybestos-Manhattan, Inc.
Middletown Stratford
ILLINOIS
Gatke Colj)oration Grizzly Brake Division of Mar Pro Inc. The L. S. Miley Company Johns-Manville Corporation
Chicago Chicago Chicago Waulceg'!n
INDIANA
Raybestos-Manhattan, Inc. H. K. Porter Company, Inc. World Bestos Company
(sub. of Firestone Tire & Rubber Co.)
Crawfordsville Huntington New Castle
JG:NTUCKY H. K. Porter Company, Inc.
Richmond
MASSACHUSETTS Auto Friction
Lawrence
MICHIGAN
American Brakebloclc - Division Ambes Corp, Birmingham
America~ Brake Shoe Company
Troy
Jt'
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-36-
NEW U<RSEY
]<'!ns-Manville Corporation R,;ddaway Manufacturing Gompany, Inc. Rayhe:stos-Manhattan, Inc. H. l<. l'orter Company, Inc.
Manville Newark Passaic Trenton
NEW YORJ.. Bendix Corporation
Troy
NORTH CAROLINA Southern Fri~ion Materials Company
Charlotte
OHIO
American Brake Shoe General Motors Corporation Maremont Corporation
Cleveland Dayton Paulding
PENNSYLVANIA
Raybestos-Manhattan, Inc. H. K. Porter Company, Inc.
Manheim Pittsburgh
TEXAS Standco Briike Lining Company
Pouston
TENNESSEE
Bendix Corporation
.,
s: VIRGINIA
(/) American Brake Shoe
Cleveland Winchester
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(Thomas Register, Dec., 1968 Ed., Fortune-1966 Plant & Product Directory of the 1000 Largest U.S. Industrial Corporations; U.S.
N Department of Commerce.)
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REPROCESSING PLANTS PRODUCING ASBESTOS CEMENT PRODUCT~'
'
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AlABAMA
U. S, Cast Iron Pipe Company GAF Corporation Cement Asbestos Products Company
LOci._TION
Anniston Mobile Woodward
CAUFORNIA
Southern Pipe & Casing Company
Johns-Manville Corporation
Johns-Manville Corporation
,
Certain-Teed Products Corporation/
Certain-Teed Products Corporaucih
Johns-Manville Corporation '
Azuza Long Beach Pittsburgh Riverside Santa Clara Stockton
,. CONNECTICUT Tile Roofing Company
Stratford
GEORGIA
Uniroyal, Inc, , GAF Corporatior:~/
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ILUNOIS
/
A~beAcme
tos Covering & Flooring Company
Asbestos Magnesia Materials Company
Fl!ntkot Compar:.y
Wester Slate Company
l'el-P1., Inc.
John!i""Manvllle Corporation
Hogansville Port Wentworth
Chicago Chicago Chicago Elmhurst Skokie Waukegan
, S. Gypsum Company
East Chicago
.-,
GHQ Dqcember 3, 1971
TO: JOllNS-Ill;NVILLE ENVIRONMEN'l'l>L l!Elii/fll 'l'ASI~ FORCE AIA/l~A HE~lBEl..( COMPANIES AIA/NA i\Diirr~U;TR1\.'l'l VL SUB-CQ!.H-liTTEE
CC: Dr. Joseph L. Goodman Ike \veaver~..
Ed Dris~~m~
C. R. hllkt'l
R. F. \\7i11L\vorth H. J. Roesch
Frank Zimmerman Bradley \valls
l~LINOIS POLLUTION CONTROL BOARD REGULATIONS ON ASBESTOS
l>ttacheq is the "Proposed Final Dr2ft" of the State of Illinois Pollution Control Bo~rd regulations on asbestos. Substantial changes of a positive nature have been made in nearly every section of the regulations as compared with' the draft published last summer.
Among the most important changes are the following:
1. The section banning the use of asbestos-containing br~ke lining;; after .l97S hil.s boc:n c] iminil.ted. \'Jhil e it mi9llt appear from the commen-Ls in the "Explanation" section of the regulutions on pa~JC 10-ll that this question is not completely settled, it is our belief thilt the Board will take no f\'lrtlwr action aguintc~t brake linings unless the Feder~l Government cloes first, in which cu.se any action taken by the state Kould be rather u.cademic.
2. The plu.nt emission standard has been raised from a level of .5 fibers per cc to a more acceptable level of 2 fibers per cc. In addition, the standard of .05 fibers per cc at the boundary line of a plant has been eliminuted completely.
3. A "no visible emissions" standard has been included in various sections of the regulations where enforce-ment of a stricter standard \vould have been a problem, if not impossible.
4. The segr:1ent of the rcqulu.tions :requiring "total enclosure" of a struclur~ unc1er t1err,oli tion before toppling of \valls could lJC~gin has been al tcrecl. to
a.. rnore-o1-less "do the Lest you can" standard.
FMSI 03023
-2-
5. 'fhe section requiring the usc of a sealant on all "fibrous" mu tcr L1ls used inside ducts or plenums has been changed to "asbestos-containing" materials only.
6. The section prohibiting the discharge of asbestoscontaining process waste water into the rivers, stream~> and sewers of t:hc stc:tte has been changed to pennit such dischar~rc if the \.'u~>tc wetter "is given t:he best avai Jc:tblc.~ trec:t tmen t consistent with technoloqical feasibility and economic reasonableness."
7. Under the Proposed Final Draft, only manufacturing plants will be required to obtain a permit from the state. The first draft required permits for any operation or activily involving asbestos.
'l'he vast majority of the above and other positive changes in the regulations reflect specific rccon~endations and corroborative evidence presented to the Board by Dr. F. L. Pundsack of Johns-Manville and Dr. Joseph L. Goodman of Raybestos-Manhattan on behalf of the l>Ili./NA at the public hearing on the regulations held October 15 in Chicago, ~nd by Dr. Geor~e W. Wright and an industry team at a meeting held with Board staff representatives in September. _ll.lso parhci~;<Jiing jn 1-hp ovrr.'1ll r:nnr<:>rntive industry effort were NH1l\. c:tncl the Friction 1-lc:tt:crials Stanc1c:trds Insti tutc. -.;.
Attached is a copy of the specific, chongcs subn.ittcd by the l~IA/i~A at Board request following the Chicago hearinq. Because of Uw -rc:tny clwnqes in the final draft, the section and sub-section numbers on the Z\Il\/Nll. reconu11cnda tions do not correspond to those in the final draft. llm1ever, as you can see, the basic changes rcconunemlcd by the li.Ili./Nll. have been adopted by the Bo.:1.rd.
It is indeed an encouraging sl.gn to find that, in this era of natibnal environmental pa11ic, a well-documented and well-presented industry case can produce results as fair and reasonable as those obtained in the state of Illinoi~;. l'1uch crecli t must go to the responsible yet fair attitude of the Illinois Pollution Control Doard, and to all those in the industry who worked long and hard on this project.
/~~:.~::////
~__....-'-------
\i. P. Raines .'
FMSI 03024
called killer
By STI;:li'f: RO"mMAN ,. Staff Writer
the end of three days of hear- management environmental ings before the !PCB, which is team to work out methods of
' "There is no doubl about it creating regulations to protect dust control. It also led to a
. , .asbestos dust is a killer H it the public and workers from special asbestos dust heai'in"
gets into your lungs."
asbestos-related ailments.
in Waukegan.
b_
TI1e man who was speaking Hearings also were held in J-M officials termed these-
was James Middleton, busi- Granite City und the Firld ries the work of a "local busy~
ness representative for the In- Museum in Chicago.
body troublemaker trying to
ternational Chemical Workers "We read a great deal ahout muddy up J-:Ws good name."
Union, Local 60, in Waukegan. emission conrrol standards," according to an 1PC l invf'sti-
said Middleton, "but we sel- gator.
Some 25 environmental ex:perts, concerned citizens and rrpresentatives of the Johns!.ianville Company plant in
dom come in contact with the people working with the products."
But the irwestigator added the investigation indrcated J-M had a great deal more to do
Waukegan sat and listened.
Middleton brought employe even though it was a leader in
Samuel T. Lawton Jr., Illi- problems to the attention of the fidd of environmental pro-
nois Pollution Control Board News-Sun reporter Steve Roth- tection for asbestos workers.
member. eyed the wiry union man last June.
' :Middleton said workers were
executive with interest.
He provided death certifi- exposed to dust when unload-
"There is a long hard road cates {)n two workers, who ir.g railroad cars of asbestos
ahe.ad to improving conditions died of ailments caused by material and making pipe 'in
(in the Waukegan plant}," long exposure to asbestos dust , the transite pipe division, as
added Middleton, "but we are in the plant.
well as in its block-making
~01':'1~.;~~ ~n.1.~~!',-! ~h~ tj~~r w~-:n
A ,.....,.,.; .... ,. ,.., ,._.,...,,.,,... cu,., ooo....tL . .OroCes.t".'.. .
J-Mwe cnn pull off our respirators cl~; j;j-~~ ~- ;;~;;;is~-~y
"Tl;c company has show'd
and work without them.''
officials to clean up t.he four us where it is making im-
plants it operates in Wauke- .provements in the plant," he
Middleton's testimony came at gan and to create a uniQn- said, "but the problem has not
., _,: hccn solved.
fl; ;;~?: t:;r ."i"~' '"~'.'.P".W"."',""'''7" om.~ ~J,' ~~;"'',i.","'~r~~:~~~''Y'<-'"~~."-!", ''"'~''".~""~U~-,",<~".ii"'i:f';:1"1'""'-"_;,';.'
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"Asbestos dust will get into
the lungs some way, if it is
~ot controlled," ~ added,
and we feel the respirator
(used by employes) is not
good."
1
Middleton said the union has adopted a wait-and-see attitude to see how far the committee can go in cleaning up the plant."
The danger not only is in the handling of asbestos, said Middleton.
"Workers leave the plant with dust on their clothes," he said. "They carry it into their cars. into the stores where other people buy products and home.
"Their children come in contact with the clust and gd it n theLr lungs. when they p:Jy nn ;;,.:, ~uu~i1 wiJI!re tiJlir TiHners sit to rest," he added.
Ml?dleton said he felt workers should be provided clor!ws which would be left in the pjant at the end of the day, or somt> means of cleaning the dust from their clothing before they went home.
Gaddam N. Redrlv an lllinois Environmental Protection Agency environ!lwnt;J! engineer. said he felt regulations '
sho1:ld stop all commercial ac- : tivity where asbestos was used ICcnlinuccl on Pag~ 4A, Col. 6) .
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Plant problen1s
James Mi?dlNon, left, business manager for the International Ch~mi~al '
~orkers llnron, Lc.cal tl~, and JJenj<lmin Foul, union president, discuss condi
t1ons at the Johns-l\lanvrlle complex In Waukegan with Charles Wikel one or
.the company's plant managers. (Staff photo)
'
.......~.':'
FMSI 03025
A_sllt~.stos dust ca]Jetl
kille11t at hea1~in~1 __,_~,~:""'-.~ I ..
IConlinuod from Page JJ
Aycr ~aid that prou:-ction
unless th~ person in charge complies with regulations.
must come at the "source" of exposure.
"We want to stop dust from getting into the atmosphere not just those who violate the re3ulations," he said.
Rdcly said the agency was recommending that mechanical exhaust of dust into the atmosph~re be prohibited.
"Any factory, plant or enterprise should have to enclose its asbestos facilities so aJI exhaust air is filtere.d," he said.
Ayers said the concern Is not
with the dust which you ser.,
"but the dust which you can-
not sec because it is too small
but can make it into your
lungs."
"
Fred Engelking, a Catapillar
Trator Co. rrsearch expert,
saio. that :he company had
made its own test of hrake lin-
ings and felt the evidence in-
conclusive to pass regulations
Reddy said he felt the spray ing of asbestos fibers should be regulated so that the fibers are _confined to the area being treated.
But he did not f!C'el that all spraying of ashestos fibers should be prevented.
lPCB is proposing that all asbestos spraying be halted.
nu~ ~t:lljau1iu Foul, presl dent of Local 60, urged the board not to halt use of asbestos spraying.
"Handled properly, asbestos is R good f;re protection material," he said, pointing to the
covering them.
"Caterpillar.
.questions
whether the intent of the . .
requlations is actually accomplished by the proposed ban or asbestos brake linings," he said referring to the 1975 cut-
off date for use of aasbestos in brake linings.
He said if testing indicates a
~e~ge; ~~!~!~, t~: ~bU~U~i~r,::;
should be qualified to ailow asbestos use in a totally en-
closed brake compartment system. This would prevent asbestos particles from getting into the air.
disastrous McCormick Place
If testing indicates that as-
fire of several years ago.
bestos brakes are harmful
then a reasonable threshhold
McCormick Place bad not limit of the dan!!er should be
been protected from fire by established, he added.
flame resistant materials and
all steel girders melted under "Place the burden on the
the intense heat.
manufacturer to design his
Howard Ayer, National Institute for Occupational Safety
product to meet reasonable, attainable standards," he sllid.
and Health of the U.S. Public Service, said that in-plant test-
"Don't just prohibit the use of asbestos in brakes."
ing for dust concentrations can be set up for about $1,100.
He said filters which employes could wear cost about
00-cents a piece..
But Colin F. Harwood, an Illinois Institute of Technology Institute research chemist said brake linings have asbes:
tos dust in them and that
He said it takes one day to train a man who knows how to use a microscope in testing techniques.
many people have asbestos deposits in their lnqgs although
they don't work with the product.
A man of average lntellig ence can learn the process in one week where he first must learn to handle a microscope.
Harwood, who testified at earlier hearings, told The News-Sun "asbestos spraying" should be stopped.
"Our primary concern is with the workers," he said. "Asbesto:, is related to lung cancer and we aim to see these people protected because
"Building sites are 'essential-
ly messy places and are hard
t? clean up," he sG.id. "Spray-
ing increases the number of
airborne particles."
ot the danger from long expo-
sure."
While J-M took no active part ni the Waukegan hearings. officials later backed the position of Dr. Fred L. Pundsack, a company' vice pre~ident who represented the Asbestos Information Association of North America in Chicago.
Pundsack said while the danger to the gcnpral public had not b(:en def1n~d ...
''\.Ve believe it is prudent and fea>ible to establish reasonable emis~ion controls that will 'jl\W!cct the puhlic and ensure that hazardous levels or asbestos will not develop in the community air in the future."
~ .' .
Dust dangers
Samuel T. Lawton Jr., IPCB board member, reads over sul>mitted testimony dealing with the dangers of asbestos dust. (Staff photo)
FMSI 03026
October 20, 1971
ILLINOIS POLLUTION CONTROL BOARD HEARING ON ASBESTOS WAUKEGAN, ILLHifOIS - OCTOBER 19, 1971
This hearing was presided over by Board Member Samuel, Lawton and was also attended by his Assistant, Timothy Harker. Others in attendance included representatives of the Johns-Manville Local 600 of the .International Chemical Harkers Un~on, Dr. Colin Harwood, of Illinois Institute of Technology Research Institute, Reporter Steve Rothman of the Waukegan "News-Sun", the newspaper that blasted J-M on the asbestos and health issue J..ast summer, ann a rPprARAnt:at.ivP. of t.hP. Il J in()j s Department of Labor.
Johns-Manville was represented by Plant Manager Chuck Wikel, Dr. Torn Davison, Cliff Sheckler, Roy vJinkworth (employee re 1 at ions) Frank Angelos, (Environmental Control) J. Robbin ~&FM District Sales Office, Chicago) and Bill Raines. Dr. Eugene S t e f 1 of Raybestos and Attorney Carol Halfpenny, representing Raybestos, also were present.
The first witn~ss was Mr. Gaddarn Reddy, Environmental Cont'rol
Engineer, Illinois Environmental Protection Agency. Mr. Reddy,
'
a native of India, spoke with such a decided accent that it was difficult to understand what he was saying. The gist of it appeared to be that the EPA (enforcement arm of the Illinois Pollution Control Setup) did not have the personnel nor the
FMSI 03027
-2-
equipment to do the kind of sampling of ambient air.that the regulations called for.
The second witness was Cliff Sheckler, speaking for the National Insulation Manufacturers Association. He gave a statement on the health aspects of Fiber Glass. This was intended to counter the allegations made.by Mr. Golinken at Chicago, although no reference to those allegations was made by Sheckler. There were no questions from the Board.
The third witness was Fred Engelking of Caterpillar Tractor. He is a Chemist who is in charge of Research and Development on Friction Materials in the Research Department of Caterpillar. He gave an excellent slid~ presentation covering the typmof equipment that Caterpillar makes that use brakes, the five different types of braking systems and some of the research Caterpillar has done. He states that no safe substitute has ever been developed for asbestos in brake linings. He showed very impressive graphs demonstrating the difference in "slip time" of asbestos containing brake linings versus sintered metal. The latter are very noisy and, worse, tend to lock, throwinq the driver i~to
Caterpillar has done research somewhat to that of Lynch. They
see no fibers~e.-}';; than 5 microns.~.. their results generally
parallel those of Lynch.
FMSJ 03028
-3-
Caterpillar wants the brake lining ban modified so that: 1. Asbestos brake linings would be permitted if in toually
enclosed brake compartments. 2. Asbestos containing brake linings would be permitted in
any event until conclusive medical evidence has been shown to prove the need for a ban on them. Even then, a threshold limit value should be assigned rather than a complete ban. (An interesting contrast to Nicholson's "Make Industry Prove It's Safe" Testimony in Chicago.)
The fourth witness was Dr. Howard Ayer of the National Institute of Occupational Safety and Health, H.E.W. He talked about sampling and calculating methods and the great variations in sampling. He talked about reliability, reproducibility and cost of sampling techniques, particularly those that would have to be used for the ambient air. It appeared that his testimony was aimed at supporting a "visible emission" versus "numerical" standard, although Ayer, expressed some doubts about the idea of a visible emission standard. It was never entirely clear who invited him to testify, although he stated that he had been "invited" the previous day.
FMSI 03029
-4-
The final witness was Mr. Middleton of Chemical Workers. He said he wanted to talk about in-plant conditions and gave a bit of background as to his interest in the subject, including the fact that he had attended Dr. Selikoff's seminar in March. He implied strongly that the Union had 11 discovered 11 the asbestos health problem and had 11 brought it to the attention of the company and g:ot the company to do something about it 11 but when one ignores those jabs, his testimony was helpful in that he said that the company and the Union had setup a joint Environmental Control Committee and that conditions were 11 improved 11 He said that J-M was making 11 progress 11 on dust control although the Union would take a 11 Wait-and-see 11 attitude. He pushed for some provision for chanqe of clothing so that workers do not take asbestos-laden clothes home from work. He also said that he wants TLV under the Occupational Safety and Health Act lowered, although he did not cite a figure. He did say that the Union and the company are now cooperating. When he completed his testimony, Cliff Sheckler rose and, speaking for Johns-Manville, thanked him for his comments.
Before adjoining the hearings, Lawton mentioned that there would
be additional hearings only if the f~ll Board chooses to ma'ke
11 substantial" changes in the proposed.regulations. that he did not think this would happen!
He implied
\
w. P. Raines
mab-12
FMSI 03030
,By Bruce .lng.;rsoll
If smoking two pacJ.::s a da)
doesn't give ym: lung cancer, there is a good ch~nce that
working with asbestos will, a
New York enYironmc:mal sci-
entist has warned.
Lun~ cancer has h:-!en solidlv lin};cd- with sno};in~ m1d \;ith
inhaling a~he~LOs fibers. William J. :t\ichol~c.n ie~tific-<l~~
new -that
mceid<!:c~<rl!?ltsevi:J~01;nd ce:Jr>ebv<ea=lssws-
Ken Towers, ~,i~tunl m.Jn~ging cdi!or of The S~nTirr.cs,
.-m,-lfc 151-2 f;:.rr.~~.:i!\~~j~-- ;,cccpls award for thismwsp<-pc-r h:-111 Inc 178th lnlanlry,
"A~bestos workers who sn~ct~ :-...::1 :-:.~ore t!1a...1 ~{) tin1es the risk of <iyin.; of lung cancer than men who neither smote cigarets nor work with asbestos," he a~serted.
lliif'lois Nalicncl Guard, a commJnily Dclion p!aquc. Prc~r,r.:ing the ~ward arc Mr~. laJvnc Horton, co-cbt.irman of' the unit's cor.'lmunity rcta:iom conin,illce, and Lt. CoL Frank A. March<>nt Jr.. l78;h commander. (Sun-Time~
Photo by Bob Bl<J-;k)
./.::..-....
Nirholson, assi&tant profes-
sor o! communitv ml'<licine at
Mount Sir.ai Sd;c.ol of I\ledi-
rine in .:\ew York Clry, ap-
peared Friday at a healing on
propcsfd st<.tc rf'gulations on t_he use :!:;d r.Janufacture of as-
bestos p:oduc:ts.
than 3,2GO product<;, rang:n;:; irom clutch linings tO ~omen's .:-o:.ts w nh!clc snow ~;Jr::!yc>d
on Christmas trees.
I;kho!siJn s::tid Durch :.tnd 5 c 'o t t i ~ h snt;lie:s ~ho..- a "SifOllg" Jir,k bC:1WC:l'n OCCUJl<i
I n t i on s w o u I d r~quire sa!c-ruards to J:e.ep a:;be:::-to~
...... ..:....~--~
~-- --=-----~-~
~rom csc-apin6 l'Clll~:rurtion
;;no buihlin:;dfr.K,Ji; i;n ~ires.
ser strin~c-nt lin~;:s oa -emis- 1
Call
;lvVGi[ht V/ulchsrs '-sions from a,be:~to~ pl:wts,
WJcl N!ll:tW u~llr:~tOs in br;.l:c
He end Harold Romer, !'lew Yor~ _Cit:'s assistant commissioner or' air rbources. un~e:J the llli:oo:s Polllnion Control
tio~ul l'Xposure to a~k;1os in ::..hi~ynr..is. ::.nd n~c<::;oth(:HOnl:t, J
rar~ fon;1 of cancer. fred L Punds::~ck. ,icl' pres-
liniags by l!J75.
: and find out how''\'inually .erery H!.;klc> cn
()-oo1 h ;:: rn:td carrit:s SI:'\'C:J':ll ;
32 :J-o/p:,nnr}... or ~~l):~!(l~ in i1~
~~
Bo:~rd to ndt'r< :z propos:d ban ide::t of rtse;.~rrh :md dL. ..:J- br:ihcs," S:Jid Co:in F. H:tr i
o n s p r;; y i n g :..~h:~!os insul:ain:; a;~d firc-proofin;;; mlt<:-
rials.
0 p men t for J('h'~-~~lamiilr Corp , \:hid, h;:s a l;;rge a,. be~l(lSJ~:::.nura:li.Jfit:~; con:nlt'x
\'. (l<:i, an ] IT R>:-:=Parl'h lil-
~lih:t\! Ci1Cn1iSt \dlO t-Xj"~flrfd
tr.l' -:~sl'C~tos p~oblc>m for tilt
c_1; ;tJ;,:-,a,- .. ~----~<-"''
b/,. ~"'-.:r l: :-.( 1 :-H\ l.:r!lh;.er.t:.
Romer pcimcd out at tl:!! hearir.~ :H 11w Fir-ld !llu~eum
of ;.;,!i..ral Biswn that hi~
;o \'.'a<Jkfpn, s:1id asl.ot:s!O~ k\.;1~ iP. l!ri'l:m :::ir arc> lo\\ ami
pCl~e no hrahh Thn;rt.
-'t:.te. - - - - - ---- - -- - .. ---- --'- - --- -.- .
r~- --~,~------
- - . :~--- _ _ _ _ , . . _ _ _ ,. _____ - - - - - - :.o. - - ............ - --~
c!t;,, Bo>ton. Pllibdrlphia and Chkr.~o alread" h;.ne outlawed a~~e,tos ~prnyin~.
Nich0bon to!cl 'Jf rc>tJrl'h lying the ri,:e in a'he,ctos u~e
'lie ('ited a rc-c..:m n pNt 10
th? :\mi~n~.J :\r;:l!en~ ''' "ri I
er,ces !'>tat:n~. "The-rei~ 11'1 e1 i:k~'<>~ th:<t i1 ~ ~nJ:ill r.u:;:.: ~-~ of ra:!HS~0.<) libPrs in mo.;r :'t!
....' ~ .
I
I
to f.!rC~tcr in:id\.1nce of :tsbcs n~C'!l!h(rs Clf tltt.~ ;r11er.I p-,~:- l
to~i,;, a disease cllaracttriz"J Llll:l afkrt h,;Jith or !r,,Jn.(,-- ,:
by a~l~, tos-iih,r ~cars on ihe it\',H
It
:!I hrngs.
'tn aJJi!iorl to tilt' 'jl::,~ in;.:
'I
AsbC'SIC>S is U~C'<l in 1110re h:~u. t}:c p~;r~;'l(~u ! :J;n~':"' r~:,!lt . ~
, ....
. - --.. '! tr 1
:!I
FMSI 03031
October 20, 197l
DcC:SK !Ii~l-101WfDU1I
:.'!\'
v
v
RE: ILJ..INOIS P01..LUTIOH C0ll'l1RCL .GOARD !i::.::ARIHG ON i\SBJ:~STOS CHICAGO
On October 15, 1971~ Dr. F. L. Puncl.sacJ:, Vice P1~esident, Research and Development,.
Jolms-lb.nville Corporation, pre.sente<l testiMony on behalf of the AIA/l~A at the second of three hearings beinr; held 1)y the Illinois Pollution Control Board on prO})Osed regulations affecting asbestos. The hearinr; Has held in Chicago's Field 11useum, and vras attended by approximately 70 people. Appearing Hith Dr. Pundsack to help anm1er questions posed by the Boc<nl. vere Dr. Joseph L. Goodman, Kedical Director, Raybestos-Ha.nhattan; Gf!orr;e L. S\ral1.ov!y }!e..nager, Occupational Environmental Control~ Johnc-Hanville i and L II, Ht>aver, Corpo:rate Director, Environmental Control, Ro.ybestos-lbnho.ttane The hcctrin[; Has chair:d by Samuel Lawton, a member of the BGard. Also present ,vere Board mumbsr .::acob Dv.Hlelle and LaHton 1 s Acl.ministro.tiv Ac>sisf.:mt~ Tir1othy Harker. Al:i_ three e.Rked Olw.:stionE during the hear:i.ni!'.
The first person to testify \ras Dr. Colin lianrood of the, Illinois Institute of Teclmolog;{ Research Institute (IITRI). Dr. Hc>.J.'vrood served as advisor to the Board on the J)roposed repue.tions, and \ms present at the r.teetinc; held on September 17 betHeen a team fror.t the incluotry and representatives of the Board (a report on this meeting by H. P . Raines Has dist:c-ibuted on SepteMber 22).
3asically, Dr . Harv10od su:;lported thE: re[\Ulationn as \~ritten. He said that \lhi1e there is no cause for panic about tbe amount of asbestos in the ambient air, controls F>hould be instituted. He .said that the requirements of the proposerr regulations are v:ithin the capab:Llities of existing technology, and that an efficiency standard or a 11no visible errissioD..s11 standard would not be sufficient; to control emissions. He also stated that brake lining \'rear contributes to the bacl::gr01mcl level in the ambient ;d_r 1 and that he has faith in the industry's
ability to develop a non-asbestos cont.':l:lning lining by 1975. Dr. Haruood promisDd
to send me a copy of his final report to the Board in the near future.
'The second })Orson to testify Has Bi::_]_ Ilichol.son of Iviount Sinai Hospital (c.. copy of hi.s prerm.x"ed r-emarks is attached). Nicholson, after- e;ivinr; the s~andard Ho1.mt Sinai pitch on the ins1.1lation worl:ers f>tudied by Dr. Selikoff, con[iratuln.tcd the
-r:lCre-
FMSl 03032
-2-
Board onits proposed ban of sprayed fireproofing. He said that.permittinc; the spraying of buildincs vlith asbestos-containinG compom1ds would be "playine Russian roulette11 uith the lives of the general public. He also said that the regulations with regard to demolition should be made stronger. He opposed the use of a numerical standard. for emissions from manufacturing facilities because of the difficulty. of accurate measuring of very low ambient air concentrations. Instead, Nicholson recommended that t!le Board adopt an equipment efficiency standard and a "no visible emissions" standard, based on the Federal EPA model., 'dhile this position was in general ac;reernent with the AIA/NA position, under questioning l!icholson said that he Hould not be opposed to ambient air testing as a sort of check-up on the efficiency standard. Vlith regarcl to brclke linings, Nicholson qu:oterll some figures shoHine; that ambient air levels. at toll booths on
the Long Island Thruvray \vere 3-4 times hic;ller than samples taken a few blocks
away (all levels Here in the nanogram per cubic meter range). Nevertheless, he did not indicate full support for the ba11, but suge;ested that the regulation be revlritten to include a clause saying that if the ~ustry could demonstrate no
hazarci from brake linings, the ban v10uld not eo into effect _(once again we oce the
uosi'Lion beinrr taken that asbestos should be coru>idered guiltv until proven safe).
The next speaker \ras a man namerr Golin}<;,en (? ~ ,, vJho identified himself as an insulation contractor in the Chicago area. Golinken started off by sayine that he had no comments to make vrith regard to the "asbestos" regulations, l:lut that he was really concerned about the hazards of fiber glass inside ducts. He then proceeded to r;ive the standard asbestos vro:.:kers union pitch against fiber glass. The Board appeared to be somewhat confused as to the raison d 1 etre for Golinken 1s presentation and had no questions.
Following a !+5 minute break for lunch, Hu.rold Romer of the l/ei'l York City Environmental Protection Administration launched- into the most v.itriolic: attack on asbestos of the entire day. By comparisonr Nicholson Has a tO\'Ier- of objectivity. Quite naturally, Romer spent considerable time on the NeH. York City experience. with spraying . He called: the asbestos that is being found in the lm1gs of citY dvrellers a "time bomb" for the future, and expressed great concern over the demolition of buildings containing asbestos products of any type. He also took broad svripes at numerous other uses of asbestos, including in talcum powder, in women's coats, as Christmas tree 11snm111 and otherso Ile supported the ban on brake lininc;s and called for close controls on every conceivable use of aobestos. Homer made numerous factual errors in his presentation . l<,or exrunple, he stated quite 1mequivocally that
-morP
FMSI 03033
-3-
EH size asbestos fibers were extremely hazardous to hur:1ru1 health. Dr . Pundsack took Romer to task on this particular e:rror, but there: vmre so many others that refuting them all Hould have taken up half the afternoono
Dr . Pundsacl: \vas next to testify. A copy of his presentation is attached~. Dr . Pundsack replied to Hicholsonts comments about asbestos levels on the Long Island Thrmvay by saying that if asbestos concentrations from brake lininG wear Here going to be high anyplace, they would be hi~h at the spot sampled, yet the levels found Here insignificant vThen compared \vith safe occupational levels. He also commented that at the lov1 levels found, the r.JRrgin of error vmr3 so high as to make the findingG useless. Follouing his prepa.red comments, Dr. Pundsack introduced Dr. Goodman, \vho reported on a study by Dr. Paul Gross in \vhich he injected brake lining dust into the lungs o;f test animals and produced no disease. Dr. Goodmm1 also commented on another study by Dr. Gross in \vhich human lungs \vere digested and the amount of fiber calculated. These tests shovmd no relationship between disease and th(~ inhalation by people in the general public of even large amounts of El'1 sized asbestos fibers~
Numerous questions vere asked of Dr. Pundsack ollovling his P.repared testimony. They dealt \lith such subjects as: loosely-bound VG locked-in products, ho'tl a visible emissions standard would \vork (the AIA/HA \ias asked to submit in vrritine; its specific recommendations in this area), the possibility of asbestos fiber accumulating in the community air, asbestos in \'later, whetherr chrysotile is less hazarJous than crocidolite, the Selikoff study of insulation workers, talc a11d GI cancer, etc. All questions vrere handled skillfu_lly by Dr. Pundsack. The total AIA/HA presentation:, including the question and' anm1er period, lasted approximately one hour. The AIA/IIA was asked to submit numerous documents, medical papers, specific recommendations and other supportine; data to the Board.
Follmring the AIA/NA presentation, Ivan Sabourin e;ave a short presentation on the Canadian-American asbestoa industry.
Hatthew !1., Svwtonic
FMSI 03034
Dr. F. L. Pundsack
to,) .;J (1 I
Presentation to Illinois Pollution Control Board
October 15, 1971
My name is Dr. Fred L. Pundsack, and I am Vice President of Research and Development for the Johns-Manville Corporation. I am an inorganic chemist witha Ph.D. degree from the University of lllinois, and I have been involved in asbestos research since 1952. I am here today representing the Asbestos Information Association, an organization sponsored by nine leading manufacturers of asbestos products.to provide information on asbestos and its health implications. The members of this Association are listed in a fact sheet which I have provided.
In the event that my presentation prompts questions relating to environmental control technology or the medical aspects of the asbestos situation, I have asked three experts in these
fields to accompany me here today to assist in answering questions of a highly technical or medical natur~. They are Dr. Joseph L. Goodman, Associate Professor, Department of Preve;ntive Medicine, Medical University of South Carolina, and Medical Director, Raybestos-Manhattan Corporation~ Mr. Isaac H. Weaver, Corporate director for Environmental Control for the
Raybestos-Manhattan Corporation; and Mr. George L. Swallow,
Manager of Occupational Environmental Control, Johns-Manville
Corporation.
FMSI 03035
\
Before proceeding, I would like to express the appreciation of the ~sbestos Irnormation Association for the opportunity to testify on the proposed asbestos regulations.
Asbestos has numerous important applications in our modern industrial society. Among these, it provides built-in protection against fire and deterioration in scores of common products in daily use. Through the years it has saved countless lives and billions of dollars inproperty damage by preventing or checking the spread of fires. Asbestos-containing acoustical products make a valuable contribution to noise abatement. Produ~ts containing a~bestos are used, among other applications, in the construction of schools, houses, theaters, factories, office and other public buildings, and in the insulation of furnaces, boilers and electrical equipment.
The asbestos industry within the state of Illinois plays an important.role in the economic life of the state and its people. The member companies of the Asbestos Information Association own and operate a total of eicjlt plants within the boundaries of the state. Some of the product lines produced at these eight plants include: asbestos-cement pipe, packings, gaskets, friction materials--including both conventional and disc brake lin-
\
ings--asbestos-cement sheet products, asbestos roofing and siding shingles, insulations, and many others. A total of 3,118
-2-
FMSI 03036
\
Illinois residents are employed at these manufacturing faci-
liti~s. Last year, these employees received a total of
$ 24.4 million in wages, salaries and fringe benefits. Services
and goods purchased within the state, such as water, electricity,
telephone service,raw materials and freight amounted to more than
$ 17
million in 1970. In addition, state, county and local taxes,
amounting to nearly a million dollars last year, helped to pay for
new schools, roads and other benefits to the state and'its
citizens. The value of goods produced at these manufacturing
locations last year totalled $ 70.1 million, with approximately
$14.5 million worth of these asbestos-containing products being
sold within the state.
As you can see, the economic contribution of the asbestos industry in the State of Illinois is by no means small: And the figures I have just given you represent only those companies that are members of the Asbestos Information Association. There are also within the state many other concerns -- both large and small--whose livelihood depends in some m~asure on the use
.'
of asbestos or asbestos-containing products. Such concerns would include many segments of the construction industry, companies engaged in the manufacture of asbestos-containing products, companies which use finished asbestos-containing products in the manufacture of other products, and many others. The economic value to the State derived by the use of asbestos by these other
- 3-
FMSI 03037
concerns is difficult to gauge, however it would certainly douqle or triple the figures I gave you earlier with regard to the contribution of the member companies of the Asbestos Information Association.
The asbestos industry has recognized for many years that there are occupational health hazards associated with the excessive inhalation of asbestos dust over long periods of time. As a result, the industry, beginning in 'the late 1920s, has sponsored and cooperated in a wide variety of scientific research projects designed to identify these hazards and to eliminate them whereever they may exist, not only in asbestos mines, mills and manufacturing plants, but also among fabricators and applicators of f.ID:i.shed asbe~tos products. Today, the asbestos. industry, either as individual companies or through the Quebec Asbestos Mining Association's sponsorship of the Institute of Occupational and Environmental Health in Montreal, is supporting medical research at such highly regarded institutions as McGill University in Montreal, Tulane University in Louisiana, St. Luke's Hospital in Cleveland, the Environmental Sciences Laboratory at Mount Sinai Hospital in New York, the Industrial Health Foundation in Pittsburgh, the University of California at Berkley, Farleigh-Dickinson University in New Jersey, the University of Pittsburgh, the Medical College of South Carolina, and a number of others, both here and overseas. In addition, the industry has cooperated extensively
-4-
FMSI 03038
in various investigations into asbestos-health conducted by agen.cies of the Federal Government, including the U.S. Publie Health Service, the Federal Environmental Protection Agency, the_National Institute of Occupational Safety and Health, and others. In the industry's own research laboratories, scientists and engineers are also engaging in work related to health, dev~loping safer packaging and handling techniques for loosely bound asbestos products and also developing and
. . .~mprovJ:ng. techn~ques for the meas' urement and control of as-
bestos emis.sions both in the work-place and in the ambient air.
As a result of these activites, over the years the industry has amassed a substantial amount of medical knowledge and technological know-how in the asbestos-health area.
Basically, the known facts about asbestos-related disease can be summed up as follows:
First, asbestos-related health risks are basically confined to the occupational and para-occupational setting.
Second, the effects of excessive inhalation of asbestos are both time and dose related. This means that asbestos-related diseases may develop, generally, only after the inhalation of substantial amounts of asbestos dust over a substantial period of time.
-5-
FMSl 03039
And third, there is presently no evidence of hazard to the general pubiic from exposure to the minute amounts of asbesto~ that may be present in community air.
Because the general purpose of the regulations under discussion here today is to prevent the emission of hazardous quantities of asbestos fibers into the air that the qeneral public breathes, I will restrict my further comments on health to this area. It is very important to realize in any discussion of a possible public health hazard from asbestos exposure that the only scientific studies we have to go on are those of groups of people in occupational and para-occupational .environments. There is no basis for assuming that data on occupational health risks associated with heavy, long term asbestos exposure can be applied to the general public without taking into consideration the vast differences in exposure between the two.
Despite the fact that the only studies in existence areof occupational and para-occupational populations, a careful analysis of the data available can give us some general information about the question of a possible public hazard from asbestos. The substance of this information is that diseases associated with occupational exposure to asbestos are dose related and that thedoses below which no measurable increase in disease occurs are far higher than any dose to which the general public is exposed.
-6-
FMSI 03040
This evidence is based on a number of epidemiological studies--three of the most prominent being one by Dr. J. Corbett HcDonald
of 10,421 past and present asbestos mining and milling workers in Quebec, a second by Dr. M. L. Newhouse of 4,500 men who were employed in a British asbestos factory between 1933 and 1964 and the Third a study by Drs. Knox, Doll and associates of 878 workers in an asbestos textile factory, also in Grea.t Britain.
Dr. McDonald, in his study, divide ~ his subjects into eight categories, based.on length of employment and severity of dust exposure. He noted that only in the highest time-exposure category, comprising five per cent of the total, was there any increase in deaths from respiratory and cardiac diseases, including lung cancer. Taken as a group, the Quebec asbestos workers had a mortality rate from all causes lower than the level expected in the general population.
Dr. Newhouse in her study in Great Britain found that workers ~ho
had 1ow and moderate occupational exposure to asbestos dust showed
a rate of deaths from diseases of the lung, including cancer of
the lung and pleura, that ~ere comparable with that of the general
public. On the other hand, another study by Dr. Newhouse of
mesothelioma (a relatively rare cancer of the lining around the
lungs) in the London area showed a small number of cases among
people who lived in close proximity to an asbestos textile plant
and also among people living in the household of an asbestos worker,
who presumably brought home quantities of the material on his
clothes from work.
The intensity of exposure experienced by these -7-
FMSI 03041
so-called para-occupationa~ populations in London is difficult to gauge, but there is every reason to believe that they were in fact higher than the low and moderate occupational levels in factories that have been shown to produce no excess of mesothelioma. These studies do, however, point up the need for proper control of emissions of asbestos from factories so that neighboring areas will not suffer para-occupational exposures to asbestos.
The Knox~Doll study, like the Newhouse and McDonald studies, confirmed the fact that low to moderate levels of asbestos exposure will not produce an excess of disease. It should always be remembered that these low to moderate levels in occupational settings inside factories were certainly higher than any to which the general public in this country is exposed.
In addition to ~e studies, there are several studies of the
effect of various doses of asbestos on laboratory animals which
also indicate that there are dose levels below which no measurable
disease effect is observed. Dr. William Smith of Fairleigh-
Dickinson University studied mesothelioma cancers in hamsters,
and his data show that below certain specific doses of asbestos,
no ~ancers were observed to develop over the entire natural life
span of the animals. Dr. Merl Stanton of the National Institute
of Health, Bethesda, Maryland, conducted a somewhat similar
study with rats and observed the same type of dose-related
response. ) f[ \\ .
' ~
'.
. '\
r
-8-
FMS\ 03042
The most well-known of the American epidemiological studies related to asbestos exposure is that made by Dr. I. J. Selikoff of 632 members of the Heat. Frost and Asbestos Insulation Workers Union in the New York/New Jersey area. These men, for the most part, are journeymen-craftsmen who work on construction sites and apply insulation to boilers, steam and hot water pipes, heating ducts, etc., during the construction of a building or a power plant. They may also be involved in tearing off old insulation. Whenone construction job is completed, they move to another construction job.
The occupational environment to which they may be exposed involves not only asbestos but also silica and particulate materials. In addition they are exposed to a variety of fumes from organic solvents and adhesives with which they work. In short, they have a widely varied and, in the past at least, a relatively uncontrolled occupational dust and fume exposure.
Dr. Selikoff found that the death rate from lung cancer was extremely high in this group of 632 workers; but that this very high mortality rate occurred almost exclusively among those workers who were cigarette smokers.
On the other hand, those workers who had no history of cigarette smoking had essentially no greater incidence of lung cancer than the general population of non-smokers.
-9-
FMSI 03043
In general, .the mortality rat~ of insulation workers reported by Selikoff is much hic;her than the rates found in studies of larger groups of peoplewho work in factories producing asbestos-containing products,and in mines and mills processing asbestos. Why the incidence of certain diseases among insulation workers is so much higher than the other groups studied is a question as yet unanswered.
Unfortunately, as is so often the,case with diseases that take from 10 to 40 years to develop, reliable data as to the past occupational exposure .of these men to asbestos and other potentially hazardous dust and fumes in their work are not available.
As a result, at the present time we have little information as to what other factors may have influenced their high rate of disease except that those insulation workers who smoked cigarettes developed lung cancer at a rate far higher than the general population who smoked.
In 1970, with a grant from the National Air Pollution Control Administratiou, The National Acade~y of Sciences called together a blue-ribbon panel of asb~stos-health experts to draft a document on the problem that would serve as the
-10-
FMSI 03044
medical basis for the Federal asbestos emission standards. Among those asked to serve on the panel were Dr. Clark Cooper of the Uni~ersity of California, Dr. Lewis Cralley of the Public Health Service, Dr. George Wright, Dr. Irving Selikoff and others.
The result of their study was a fifty-three page document on asbestos/health. As a conclusipn to this part of my presentation, I would like to read a few pertinent excerpts from thereport, which constitvtes the most up-to-date evaluation of the asbestos-health problem that is available.
On page 20, the report states (quote) We cannot.extrapolate from the mortality experience of those who are directly and indirectly exposed in their employment to the general public who have had moderate or slight exposure from ambient air. There is evidence to suggest a gradient of effect from direct occupational, to indirect occupational, to family and neighborhood situations, in all of which dust concentrations are probably high by comparison with most community air. This suggests that there are levels of asbestos exposure that will not be associated with any
-10 a-
FMSl 03045
detectable risk~ What those levels are is not known, but there is no evidence that persons in the general population--without occupational, household or neighborhood exposures--have any increased risk of neoplasm, even though there may be ferruginous bodies or fibers in their lungs (end quote) .
In the conclusion and recommendation section of the report for the National Academy of Sciences, the following statements are made~ (quote) At present, there is no evidence that the small numbers of fibers found in most members of the general population affect health or longevity. Asbestos is too important in our ~echnology and economy for its essential use to be stopped. But, because ot the known serious ettects ot uncontrolled inhalation of asbestos minerals in industry. . . it would be highly imprudent to permit unrestricted additional contamination of the public environment with asbestos (end quote).
I believe that these statements from the report adequately express the position of the asbestos industry with regard to the health hazards of asbestos. We do not believe that at pre~ent the general public is in danger from the minute amounts of asbestos that exist in the ambient air. However we also believe that it is prudent and feasible to establish reasonable emission controls that will protect the public and ensure that hazardous levels of asbestos will n9t develop in the community air in the future.
-11-
FMS\ 03046
With this po.sition in mind, I. would now like to discuss the asbestos regulations proposed for the State of Illinois. To begin with, I would like to commend the Illinois Pollution Control Board for its efforts to ensure a safe environment for the State and all its citizens. Your credentials as a progressive yet fair control board are well known and respected in environ~ mental circles throughout the nation.
While the asbestos industry as reP.resented by the Asbestos Informati6n Association is of the positionthat there is presently no hazard to the general public from the minute amounts of asbestos existing in the community air, we nevertheless are in favor of regulations designed to accomplish one or more of the following three objectives:
One, to ensure the health and safety of those occupationally exposed to asbestos fiber.
Two, to prevent possibly hazardous amounts of asbestos fiber from escaping into the ambient air, and
Three, to eliminate, where possible, the nuisance of even small amounts of asbestos fiber from escaping into the ambient air. While this third point is not directly related to health because of the small amounts of fiber involved, we wholeheartedly support the position that the environment should be as clean as possible.
For these reasons, we support most of.the items in the proposed regulations. However, we do have several specific comments and
-12-
FMSI 03047
suggestions .to make regarding. the regulations that we hope will be of help to the Board in arriving at a final document that will not only be effective but also practical and reasonable. I will discuss the sections upon which we wish to comment in the order in which they appear in the regulations.
;. Our first suggestion is with regard to Part II: General Requirements, S.ection 201. This section calls for the obtaining of a permit to engage in any activity ~hich could discharge asbestos fiber into the environment. We feel that this section is not specific enough with regard to which activities would be covered. As you are probably aware, in the vast majority of asbestoscontaining products used in the country, the asbestos is locked in place with cement, plastics or other binding materials, and does not constitute a source of emissions to the atmosphere. Asbestos-cement pipe and vinyl-asbestos floor tile are examples of such products. Other products and activities do constitute possible emission sources, and under the regulation would require a permit. If it would be of help to the Board, the Association I represent would be most willing to prepare a list of those products in common use where the asbestos is in a non-locked-in or loosely-bound state and thus co~stitute a possible emission source which would require a permit ..
As to Section 201, Sub-section B, requiring a satisfactory
course of health instruction for employees in those
industries involving the handling of loose or loosely-bound
asbestos products, I would like to point out that
-13-
FMSI 03048
the various trade associations in the asbestos industry have over the years produced a number of safety practices manuals and booklets dealing with various sections of the industry. The Asbestos Information Association would therefore recommend for your consideration as instructional material for use under Section 201, Sub-section B, the safety practices booklets which I have submitted to the Board with my presentation. The four booklets are: 1. Recommended Safety Practices for Handling Asbestos Fiber
2. Recommended Health Safety Pract' ices for Handling and Fab-
ricating'Asbestos Textile Products. 3. Recommended Practices for Fabricating, Handling and Apply-
ing Asbestos-Cement Products in the Building and Construetion Industries ... and 4. Recommended Health Safety Practices for Handling and Applying Thermal Insulation Products Containing Asbestos. Under Part V, Section 501, it is our opinion that Subsection B, which requires the enclosure of walls before toppling during demolition, is both impractical and unnecessary. We know of no suitable method for enclosing the walls of a structure during demolition. Even more important is the fact that there is, in reality, very little asbestos used in the construction of a modern medium-sized or high~rise structure. In addition, dust counts taken during the demolition of a building in
-14-
FMSI 03049
Easton, Pennsylvania, which did contain significant quantities
of asbestos products, showed very little dispersion of fiber into the surrounding air, both upwind and downwind of the
demolition site. This is due to the fact that most asbestos-
containing products in which the fiber is locked-in with ce-
ment, plastic or other binding materials do not readily re-
lease fiber in the atmosphere, even during demolition. Sub-
section A of Section 501 requires the prior removal before
toppling of boiler and pipe insulations ... two asbestos-
containing products that might release dust from improper
demolition. Since this will remove any loosely-bound asbestos
products from the structure, we believe enclosure of the
walls to be unnecessary, and recommend that simple wetting
of the walls to be toppled would be sufficient to control the
dispersion of dust from whatever small amount of asbestos-
contain~ng products the-walls might ~oritain.
With regard to Part VI, Section 601 of the regulations, we would like to recommend for your consideration a completely new approach to the control of asbestos emissions from manufacturing
-15-
FMSt 03050
operations. As presently written, the regulations call for the establishment of a numerical emission standard of .5 fibers per cubic centimeter of air from any manufacturing operation, and .05 fibers per cc of air at the boundary line of the plant or factory.
We would recommend that Section 601 of the regulations be rewritten so as to substitute a control practice standard for the present numerical emission standard. The reasons for this recommended ~pproach are varied, but are primarily based on the lack of specific data with regard to safe non-occupational levels and the difficulty of accurate and meanin~ful emission sampling techniques at very low fiber concentrations.
The Federal Environmental Protection Agency studied this problem very carefully in preparing its national emission standards on asbestos, and arrived at the conclusion that a numerical standard was impractical at this time. In this regard, I would like to read a few excerpts from a document prepared by the EPA as justification for this viewpoint.
-16-
FMSI 03051
The document states that ideally, national emission standards
for asbestos would be established on a concentration basis
related to health effects and would provide an ample margin of
protection to the public health regardless of the number of
sources in a given geographical area. There are many practical
considerations, the report goes on, which prohibit the establish-
ment of a numerical standard at this time.
Foremost of these problems is the lack of a data base.This base is lacking from both the health-effects standpoint for non-occupa~ional exposure and the emissions standpoint. The majority of data available on asbestos health effects is related to occupational .::xposu:r:E! <:mel cc:mnut. be readily ext:rapolated to non-occupational levels.
A little later on, the report states that (quote) a control practice appxach to reducing asbestos exposure levels offers a practical alternative to numerical emission limits. A major advantage of a control practice standard would be 'realized in enforcement. Inspectors could be easily trained to certify compliance with control practice regulations (end quote).
The report goes on.to describe some of the many difficulties involve in asbestos sampling and analysis, especially with regard to emissions into the ambien.t air, and conclud~s that present tephniques are not only time consuming and expensive, but that they
-17-
FMSI 03052
also tend to distort the concentration of asbestos in the sample being analyzed and are hence not meaningful in establishing th~ actual amount of asbestos being emitted into the atmosphere.
The National Academy of Sciences Committee report on asbestos health, which I quoted from earlier, agrees with the EPA position on numerical standards. It states (quote) because of methodologic and other uncertainties, it is not yet feasible to base control on numerical ambient air quality standards (end quote).
I will not go into detail on the specifics of a control practice standard since they would be primarily of an en~ineering nature, however, I will subwii.:. [oJ.: yuuJ.: considera.L.ion, a.s sooi!. as they a:Le published, the asbestos. emission standards proposed by the Environmental Protection Agency. These standards will contain sufficient information to set up a similar program for the State of Ill
Section 602 of Part IV of the regulations dealij with the discharge of asbestos-containing waste into the sewage systems or waters of the state. We believe that this section is unnecessary. In the first place, the water pollution control systems in use in most asbestos manufacturing plants across the state effectively remove the majority of asbestos was~es from the effluent before discharge into state waters.
-18-
!
I
I
FMSl 03053
Secondly, sewage plants also remove asbestos fibers from waste water during purification. In reality, the high dillution of small quantities of asbestos fibers in water is as effective and safe a method for the disposal of asbestos wastes as could be devised. There.is no evidence that the swallowing of small amounts of asbestos constitutes any health hazard whatever.
In addition, studies conducted by Johns-Manville have found small amounts of asbestos fiber iQ samples of water tested from sources all over the United States, including well and spring water. The reason for this is quite simple. Asbestosbearing serpentine rock is to be found in a majority of the states of the union, including Illinois, and the simple process of water flowing over and through these rocks errodes a certain amount of asbestos fiber.
Thus, we have all been drinking tiny amounts of asbestos in our water since birth, without any discernable adverse effects.
In Part VII, Section 701 of the regulations, we would recommend the addition of the word ~visible" in the next to the last line, so that the amended section would read: "No product which may emit
-19-
FMSI 03054
asbestos-fiber during its transportation shall be transported unless such product is enclosed in such a manner as to preclude the "visible'" emission of asbestos fiber into the ambient air 11 The problem here is once again with analysis techniques and enforcement. The EPA has gone to a (quote) no visible emissions (end quote) standard in circumstances similar to this one, and we would recommend to the Board that this also be applied in Illinois. This would also be useful in other sections of the proposed regulations where measurement and enforcement would tend tq be extremely difficult if not impossible.
Our final comment is with regard to Par~ VI!, Sectiom 702, which would prohibit the use of asbestos in the brake lining of vehicles manufactured after January 1, 1975, and sold for use within the State of Ill inc is.. ~"1e belie~.7 e that O!'l tl"le basis of tb.e e~~i::!tir1g ccic!:'!ti.fic evidence such a prohibition is completely unnecessary. In 1968, this question was investigated thoroughly by the United States Public Health Service, and a report on these investigations by Jeremiah R. Lynch, entitled "Brake Lining Decomposition Products" was published in the Journal of the Air Pollution Control Association. The report stated that (quote) except in all but the most extreme driving conditions, only a very small fraction of the 30 to 50 per cent asbestos present in a brake lining escapes into the atmosphere as free fiber {end quote). Lynch found that the average amount of free fiber ~eleased was less than one per cent of the fiber present in the brake lining composition. The percentage was higher only under conditions that would have resulted in brake failure. Lynch further
-20-
FMSI 03055
,,
reported that the majority of the fiber in linings was converted
into an inert non~fibrous material'by the heat of friction, and
concluded that the use of asbestos-containing brake linings was
"an inconsequential health factor in urban air pollution"" His
conclusion is reasonable in light of the fact that hundreds of millions
of cars using asbestos-containing brake linings have been stopping
andstarting in this country for more than half a century, and yet there
has been no epidemic of asbestos-related disease among the general
public nor have significant quantities of asbestos been demonstrated
to exist in the community air. While we consider this evidence to
be conclusive, if the Board is still concerned about asbestos emissions
from brake linings, you will be interested to know that the Federal
.Env i:t,unmeni:.al :i?roi:.eci:.ion Agency has coni:.raci:.ed wii:.h i:.he Bendix Cor-
poration to do additional tests in this area. This study is due
for completion in June of 1972, and we would recommend that the Board,
at the very least, await the outcome of the EPA study before making
a final decision on asbestos-containing brake linings" It is our
belief that the Bendix study will confirm the conclusion reached by
Lynch as to the safety of asbestos-containing brake linings. Th~s concludes my presentation on the proposed regulations. I
have submitted for your consideration copies of all the medical papers,
reports, booklets and documents that I referred to in my presentation.
I would once again like to express the appreciation of the Asbestos
Information Association for the opportunity to appear here this
morning. Thank youo
- 21 -
FMSI 03056
I
-
PROPOSED NATIONAL EMISSION STANDARDS FOR ASBESTOS
COMMENTS .Ai'\ID SUGGESTIONS FROM
ASBESTOS INFORMATION ASSOCIATION/NORTH AMERICA
AUGUST 11, 1971
FMSI 03057
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...
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ASBESTOS MINING AND MILLING "
''
FMSI 03058
,1.1 Asbestos Mining
.
1.1.2 Blasting
This standard is considered unnecessary and unworkable for the following reasons:
(1) The ore bodies in their natural state are wet. The California ores of the Coalinga type contain approximately 20% moisture. The U.S. chrysotile ores of the Jeffrey type contain about 8% moisture. In addi-tion, the subsurface open pit mines are naturally surface wetted by water seepage from the pit walls, and by rain and snow.
(2) It could be impossible to schedule blasting operations to conform to the low wind velocity and rain requirement.
1.1.4 .Ore Hauling
1.1.4.1 Dust Covers
Vehicles used to haul dry asbestos on all mine owned property shall be equipped with suitable covers.
1.1.4.2 we~ting
Where sufficient ~ater is available dry ore shall be
wetted thoroughly during transportat~on~
1. 1. 4. 3 Public Roads
Vehicles used to haul asbestos ores on public roads shall be equipped with suitable covers.
1.2 Asbestos Milling
1.2.1 Ore Dumping
Asbestos emissions resulting from dumpi~g of asbestos ore shall be minimized by wetting prior to or during dumping' and/or by enclosure of the dumping area.
1.2.2 Ore Dumps
Ore dumps open to the atmosphere must be maintained in a
wet state.
.'
FMSl 03059
1.2.3 Conveyors All external conveyors ~sed to transport ore must be so constructed as to prevent spillag~ of the ore to the ground. All external conveyors used to transport tailings or loose asbestos containing materials must be of the totally enclosed type. 1.2.7 Product Packaging
1.2.7.1 Individual Packaging We wish to reserve comment on the packaging portion of this standard until a program investigating packaging and shipping methods that is presently underway is completed. We suggest that the bags be printed \vith the label presently being used by the member companies of the Quebec Asbestos Mining Association. 1.2.8 Tailings Dumps Asbestos mill tailings dumps shall be stabilized, wetted or otherwise treated in order to control dust emissions.
.'
FMS\ 03060
_, ,.
..
ASBESTOS PROCESSING AND PRODUCT USE
'
.' .
FMSI 03061
We suggest, in order to simplify the wording of the standards, that asbestos using products be divided into three categories and these categories be referred to in the standards.
These categories are:
(1} locked in
Asbestos containing products where the asbestos is firmly bound-in a matrix of polymeric, cementitious or other binding materials.
Examples of such products would be:
vinyl asbestos floor tile asbestos reinforced plastics asbestos reinforced gaskets and packings asbestos cement pipe asbestos cement sheets and shingles asbestos reinforced brake linings and clutch facings asbestos reinforced paper ana roofing felts.
(2} unlocked
Products where the asbesos fiber is loosely bound and could pose an emission problem.
Examples of _such products would be:
calcium silicate insulation asbestos containing insulating cements
(3} asbestos textiles
Our suggested modifications to this section of the standards utilizes these categories and are as follows:
1.3. Asbestos Processing
1.3.3 Product Shipment
1.3.3.1 Labeling
All Category 2 (unlocked) asbestos fiber containing prod~cts must be labeled as to asbestos content.
1:3~3.2 Packaging
All Category 2 (unlocked) asbestos containing ~roducts must be packaged in dust-t~ght containers.
FMSI 03062
.-
1. 3. 3. 3' Special Products. Special products in the group 2 category (unlocked) such as dry, powdery, asbestos cement mixes containing loose asbestos must be packaged according to Section 1.2.7. 1.4 Product.use 1.4.1 Block Insulation 1.4.1.1 Premolded or Prefabricated Insulation To the maximum extent possible, contractors installing asbestos containing block insulation in areas open to the atmosphere shall utilize premolded or prefabricated shapes which require a minimum of cutting or grinding. 1.4.1.2 Field Fabrication Where field fabrication is unavoidable, properly designed hoods exhausting to fabric filters or devices of equivalent efficiency as described in Section 2.1 shall be installed on power tools used for cutting and grinding. 1.4.2 Asbestos Containing Powders Asbestos containing powders shall be wetted immediately upon opening shi~ping container prior to removal of contents. 1.5 Waste Disposal and Demolition 1.5.2 Waste Disposal Asbestos bearing waste materials shall be disposed of by methods which prevent release of asbestos into the atmosphere during all phases of the disposal. 1.6 Specific Prohibitions 1.6.1 Sprayed Asbestos Fireproofing The application of asbestos containing fireproofing on buildings by means of spraying is prohibited.
FMSI 03063
.
EQUIPMENT SPECIFICATIONS AND MAINTENANCE ,
FMSI 03064
..
2.1 Equipment Specifications
2.1.1 Fabric Filters
2.1.1.2 Bypasses
No control system shall employ bypasses unless such devices are clearly required for start-up purposes or are required to prevent damage to the filters in high temperature apolicatiGns.
2.1.2.1 Scrubbers
We suggest that the following sentence be added to this paragraph:
;'Low energy scrubbers may be used when it can be demonstrated that their efficiency is equal to that of the high energy Venturi type specified in the previous sentence."
2.2 Equipment Main~enance
We suggest that the wording of the unannounced maintenance inspections included in the first paragraph of this peading be modified to hP. identical to that in the Occupational Safety and Health Ac.t Re,cord Form.
2.2.2 Scrubbers
We suggest that the .follmving phrase be added to this paragraph:
"Unless it can be demonstrated that the required efficiency of the unit can be maintained with a lower pressure drop."
0
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FMS\ 03065
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NATIO:-.IAL ENISS IC\' STAC.:1J,\RJ FOR iiSBESTOS
;:---
FMSI 03066
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Table' of Contents
I. Introd~ction II. Emission Stnndards III. Justification IV. Appendices
. .-L, ' .- --......
FMS\ 03067
I. Introduction
...: . / .: ........f ...
As cmpm-:ered l>y Section 112 of the Clcim Air Act as Amer~de<l 1970, the .Administrator of. the l::!~Virom;~cn::<.!l Ptotcction Agency issues the follo;dng proposed st.:cc5~~d for nshcstos c:ni.ssion sources. T;li <:r:tLon is taken s~bscquent to n&~iug asb~stos as a ha~ardous air poll~tant on March 31, 1971. It is the intent of this standard to reduce t~c level of asbestos emissions through the D??lication of required cont~ol practices. This standard establishes minimum r~quirements for emission cc~trol end
should not be construed -::ts limiting rc.orc stringent mc<1sures.
,__
r
The scope of uses of asbestos and asbestos containing products is extre~cly large in the United ~tates. New uses are being.dev~loped continunlly; n!any uithc~t regard to atmospheric emissions. Scr:1e uses heve been dcten'i1ined by <'lir pollutio:1 control offici."als to gcr!~'--~'te a degree of atmospheric emissions unwarranted by the value of t~csc uses, and prohibition of such uses is proposed
.c-.:-
FMSI 03068
n. Emission
- <:.
I ':-
1.1 As1)cstos N'i.nin?,_
.
' ... ~ .._
1.1.1.1 D1._y_'Dr:!:__lli_:_1_3 - All air s~lCpt or dry drills shall be
equipped with fabric filter devices for collection of drillinz debris.
1.1.1.2 Wet Drillin~ -Wet drills sh~ll be equipped with cycl~nc collectors- fer collricting entrained mists.
1.1.2 Blasting_- Smf;_;cc blasting of ore deiJosits sh3ll ah2.ys be preceded by surf.ncc ':-Jetting and be limited to the follo~Ting atmosphe~ic conditions.
or. 1. lo_y surf2.cCV~ind velocity (0-3 mph) 2. ra'in
..'
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1.1.3 Ro2.d Trcat!lc0:1t - }!ir.e ro<1ds s"rf.:1ccd ~-Tith asbestos tai.lings shall bct-;:cated-;;-i-tl~ Patc:c or chcr1ical aeents to cont-rol dusi.: from
vchitlc traffic.
1.1.4 Ore Hnuling
1.1.4.1 Dust Covers -vehicles used to hgul asbestos ore on
mine o,,ned prope-rty shall be equipped Hith dust covers.
1.1..1~.2 Hett~1:..3. - \7here sufficient Hater is av.1il<1ble the ore shall be :-;etted thotou&bly during transport;:;tion.
1.1.4. 3 PL:b JJ.c i!.oads_ - Vc~1 ic les used to lwu 1 nsbcs tos orcs
on public roads reust be of Just tight construction.
1.2 Asbestos Milling
\
1.2.1 Ore D~:r:t~i~:& - .t\::>Ocstos cr:lissions resulting from du~~:,ir-..G of asbestos ot.:; 0hall be l!li~1itnized by "t7ctting prior to clumping or enclosure of the clu;;:pL:s arc3.
1 .. 2.2 _Q!.~~._D~~.. - Ore c:~t~l?S open to ;:~~c .-'1tt':1osphere s~st be ;.:.1L~:.:c:1ir.cd in <1 ~Jet ::;i:.:Jte Lhro'Jg11 the t..'.SC of Fc:r:.~~12~~cnt sprinkler systc~ns.
fMS\ 03069
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tnilin;:;s or loose a!;bestos co::tt;ini::~ -.m.1tc.rir1ls must be of tbc'
to~ally enclosed typd.
..
1.2.l~ Shc Dr):ers. - As~)cstos ore dryer.e:<h<lust must be trc~tctl in fabric filter insta}lations or by devices of equivalent efficiency as described in Section 2.1.
1.2. 5 Ore Crushc>:s - All (~ust emissions from ore crushers s1H!ll be ventilated to fabric filters or ~cvices of equivalent efficiency as described in Section 2.1 prior to discharge into the atmosphere.
1.2.6 Nill Air- All forced cxh0ust gases from asbestos miUs n:ust be treated in fabric filters or clevices of equivalent efficiency as described in Section 2.1.
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L:L7.1 In9_i_vi._9~:d P<.ck-'P:_i_t::_1- All fm::-,1s of <Jsbcs':os fi1Jcr
n;ust be p<1ckagcd in dt~st tight contairte:rs, cc:1p~hl~ of l::ith., standing l~ drops, oee c.:1ch on :-ant, b.sck ::~nd e1~t!s from :t i height of fbur feet without leakagc,and labell~d as to their
asbestos content.
1.2.7.2 Bulk Shin~cnt - Bul~ shioment shall be in dust tight
vehicles labelied-:;3'to their <.1sb~stos content. Loading <md unloading reust be accomplished in a manner which does not exhaust asbestos to the atmosphere ~Tithout the control equivalent of fabric filters as described in Section 2.1.
L 2.8 T:::iH.ngs Durr:p3_ - Asbestos mLll tailings c1un~ps .shall be stHbilizcd, ~letted, or otl:cn1isc tre:!ted to prever;t cust emissions.
1.3 Asbestos "ProccssiE_Z_
1.3.1 Han:,JJ:lcturJ-2~- i'l<1;"~U[octurcrs of prot1ucts cont.'lini.ng .?.~;0estos must control ell at~osph~ric disch~rges o gas stresms used for manufacture or dust rc~ov:!l by fabric filtration dev~ccs or devices . of C<pivalcnt efficic:1cy, as d<=scc!.'b2c1 in ;)cction 2.1, except ~-;h<=re explosion hm::.~rds ot :.:.:;tct:!.als prQolc<:>s e;c:.st, i!l u:1ich c.:1sc ~.;ct collectors, .:15 dcscri~ed in Section 2.1.2 rn.:1y be u~e~.
.-.:.-;..--
FMSI 03070
l~ 3. 2 ,VA_ n l:_i) n t ~_:!- -~},_:-, - Tn 0p:~ r;::.: i.nns. 1:i1~ '."C ,i :1,-~ l3n t c o~>.cl i. t i Oi~S
rt..;._:,ult~-.:~~~ tl1c c;:1iss.:..c:: of sig::if-Lc:-!:"!i.: ~:noL~ntsor~s~)C!:>.loS f'!c::1
general V8ntilation atr, cviclencad by presence of visible acctle,ul<1tions of a:Ja()stos Otl sucf~ccs .::dj<~ccnt to the pl.::ce of VC!:!tilntion, the vent:U:1tion <lir D''.lSt be i.:~ceal~ed by fabric
filtration or devices of o;uivalcnt efficiency as described in Section 2.1.
' ......
1.3.3.1 Labc],_lit':Jl- All products containing asbestos ::1us1~ oc
labelled as to.co~tcnt.
1.3.3.2 l'er.~'2i;-,g_ - Asbestos -proch.1cts must be packaged Ja dust tight containers except those products such as filled plastics which do not readily dust.
1.3.3.3 Spcci.::1 P~:od.1cts - Those p1oducts such as asbestos cement mixes co"t'1i.ning loosely bound asbestos must be packaged ace orcl in;; ~9 Sec~ io:r-1:2. 7.
1.4.1 Dlock Insulnticn
1.4.1.1 Pre-:-:".,)J~c:?-5 It~sul:Jt_ion - To the ma~d.mLi:::J extent po.ssi0le contractors instnlling as~estos containing block insulati6n in areas open to the 2t~osphcre shall utilize pre-molded.shapes which do not require cutting or grinding.
1.!~. 1. 2 l'ie ld_)j!~ '."i..0.-S ion - H:1e:r:e field f;:>brication is unavoit1eble, high ".'e~~cr::i.ty 1loods exh2usting to f:.lbrf.c filtGrs or devices ~f e~uiv3le~t cffici~ncy as described in Section 2.1 shall be install~d on tools used for cutting and grinding
.
1.!~. 2 .'\s_lle ~!: os C_s:~:t ~i_r,_i_:.:;..;, I'c,.;c'. !?.!.S_ - Asbcs l:os containing po,H.lc r n sh:1ll be :ctted r:cicr to c:.:pcs.1re to-th'c <tt!;~osp;1cre ~,hen used in areas without air pcllut~on cc~trols as described in Section 2.1.
FMSI 03071
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ss1.5.1 Rt~'"lovnl o'C As~estos Co:-.L.,ti.:1ir.~- Jpsul.cticn - Hhcn -rer:toving
asb e s to;-f~.;;-~~1--;-tio;-- rc:-:~l s t r~:~-~ u res-; o::t a :1.-; i. t~8 i"n e;<c c of 50 los.
of insulation or fireprocfin:;, c>::: {;;~c:-t t.:t1ch structures .:~re dc:-:1o~.i.:;hcd
contractors shall utilize tl!c host av~il.:1ble ~ca":1s to limit dust
cmiBsions from the ODerntio:1. Such :::':!~ns t:v1y include but not be
li~itcd to:
A. Enclost.:re B i! e t ti. ng
1.5.2 Haste Di.S!)Os_,_l_- As0estos bearing ~-!<lste materials s~1all be
segregated frc:>J ot:v.c1' solid ;-:aste. 3nd disposed of by a n!ethod H'li.ch
prevents release of asbestos into the atmosphere during all pltnsas of the disposal.
__.._
r.
1. 6. 1 _Jl_E_?...z.~j_1-s1::_:: s t 02.__]__:;.:2~:1 t i_~;._:::.o_~ F i n:~Droo f i.:::.3_ - 'I"he ai?P l i.e~ t iot~ of as~e~tvs cuutaining insulntLon .:1ud tircproofing by means of spraying is prohibited.~
1.6.2 R_i';persi.:i_C U~e~- Ar-.y use of ;.:.sbestos or asbestos co:<t3i.ni~g ~11ateri.sls in .po~i(:er {or!n \;hich involves d5.sp~t"'sing the 1~1.ntcrial in the environment is prohibited.
2.1.1 -::hr:Lc Filte_:;.Q.- Fll:Hic filters specified by this regulation shall consist of the follo~-;i:1g.
2.1.1.1 Construction- The inlet side of f~bric filters shall be of leakrroof construction or maint~ined under negRtivc pressure~
2.1.1.2 l3J.:PJS_:_>_es- ~:o co:1trol :>_lstem shall employ hyp<>sscs unless such devices urc_clearly required for start-up purposes.
2.1.1.3 Hol2_?~ls -Provisions shall be inclucled for emptying dust hoppers without rcle~se of asbestos to the atmosphere.
2. 1. 1. 4 F <1 h ri. c s
2.l.l.l~.l i!~Luro1l F~!1ric0--; Piotur.:1l fiber filter' f~~hrics
slu1ll ~1:'we -:_1-r.~;-:~-~7-~:~:1-J'-i"-;;_;-Fc rc1c ab il:. ty of 2 0 c fr:l/ ft2 c. t
i/2 in. 1!2 0.
-""=-
FMSI 03072
2 .. 1.2.1 S<::!'!bi~~:__t~::.- Sc!:t:hbers used ~-:here faOr~.c filters c.-.~~1~-..ct be ins.t:-1llcd ~:;b~lll be. o.C ti1c ~1ieh ct1e:cgy ven:.:t!r.i. tyl)l:! o:-:.;r;.:l:c~..! with above 40 in. w.3. pressure dror. 2:.1.2.2 Ot~-~12-~~~ces.- Altcrn.-:tive devices usee~ "t;.rhcrc r~~)t'"ic filters can be ins~nlled nrust be dc~onstrated by the user to
b~ve control performance cquivslent or superior to fab~ic filters.
control eqnip:~~ent reqc.!i,:.eci hy thii;--x.e;:;ulotion s~vtll be rezular 1.y c-.<.nntained to insure hi6h efTicicncy. UnGmWt!nced main t9r..:1-:1CC in::;::>ections
\lill be per.forr.~cd b:;r authorized pcrsonr..cl <~ncl the finc1:tng of r.ny o:: the olJ.m7ing conditions ~Jl.l.L be consldered a vio:Lation o.l this >::P.g~..L~tu.on.
2.2.1 Fabric Filters 2,2.1.1 ~xtern.:;_l__!:,~~.:=~.s-- The presence of e:(ternal lc~kin;~ of untreated ns~estos contD~nlng gases fro~ dtlCt ~or\, hoppers, discharge valves, senl faces, etc, will be a violation.
2,2,1.2 Rupturer\ :Sr1.;.;s- The presence of torn or n.:l)tllred b~ss
in <ln Opera f:-x;Lg sys-t-c-; ~Till be (! ViOl~ t ion
2,2.1.3 Im~r.opcrlv rositionc~ n~~s - The presence of any h~3 ~ot properly' po~-it:f""Q-;_~cdtQ-;~~:c,/c~{t--l-e~lkcl;e ~.;ill be a vioJ.aU.on,
2. 2 .1.4 Holes - The pr.c<~ence of a"y ba:~ contnin:Lng .:1 hole
larecr th;n- !i:f di<Ji!~ci:er ~.:1.1.1 be ~ viola:.:ion.
2,2,1.5 hTorn n_:~~~- - T~1e prcse:1ce of ~ny bt~z Hi'.:h 1:~orc t1::_1..:1 one pinhoie or being badly worn or t\ea~barc will be a violnticn. 2.2.1.6 Housc~<cco:Lng - The presc~1cc of '-!ccur~lt.~lo.tions of ;;1~~~)cstos particles ip.- ti:c Z.lc-~;n "J.r sic!:.:- of bo.;)1ouses <1ft e.:: repair or replace~~nt wi!l constitute a violation.
1
2. 2.. ~. 1 llr;~~s llY__!:~-c~-~Z'- - A~1y scl:~.;~)ber operil t :Ln:3 H::. th lc s ~ th::'.n
l;O'' r o2 prcs~>'t-::e :~cq~ .... -:.ll he a ..y).ol<cti.on.
FMSI 03073
2.2.2.2 l.c~ks - c\!:.y cxtcrn.::1l lcn:(s of untreiltcd csbcstos \ .. t.nin LG~; ;,;..l!:-._ l~r,,' ct!C\,.."0!.~:,\ fJ;:l~ir;L;;~, '<:-tc'~~. ..,iJ..1.1 i:.~- ~~' V."_\)~ :lt~_or~. 2.2.2,3 Scc.!hb_:!.:..:~?._l:_~IJ.:.~- .\ny sc:r:uhbe>: operC'.t.lng Hith less scrubbing fluid flow rate th~n its design requirement will be a violnt:ion. 2.2.3 Altcrn3tive Devices - Inspection criteria for alternative dcviccs~ili. be est2 1.Jlisl~cJ <1t tiH~ time of their certif.lc&tion.
;:--
..
FMSI 03074
Friction Materials Standards Institute, Inc., 370 Lexin~tgn Avenue, New York, N. Y.
BULLETIN
N 0. 4 1 1
September 9, 1971
ASBESTOS STUDY COMMITTEE FORMATION Mr. J. W. Greenen, wishes to announce the formation of a new Committee, the Asbestos Study Committee within the Friction Materials Standards Institute, Inc.
The members of this Committee are as follows:
Asbestos Study Committee
Dr. E. P. Stefl, Chairman Raybestos-Manhattan, Inc.
M . J. c. Henning Dr. w. Spurgeon Mr. w. B. Reitze
World Bestos Company Bendix Corporation Johns-Manville Corporation
Mr. J. B. Graham
Carlisle Corporation
.;-,H. 6~ ~ ~_._~,
E. W. DR ISLANE Executive Secretary
Distribution: General Active Members 11 Regional Members
FMSI 03075
c::;~--~~ -~ ~ } ; :.I--~~ ~~~:=~~:::._,:~c::~. ~:.~,,;::~~,. ,~t,: ~.::~}2~~::.,~;~:~,,:;~~~~(-~ ~~ ~ii~IJ Eit,::,~ IT.En:T{f~F7E; ~-ff;t~~~;~-fi ~ :'_ -:
.;. ~4-" ~.,
~ n 71-lG
~~~esto~ ahd Spray Insulation
.\ \
E>:PLl:JiATf-ON OF PROPOSED H.~GULi'~"l'IOUS
Science is pointing its medical ~ingor at a~bestos a~d
dc5cribin~ t.he "nirac-'Le fibe7:" f:!f> a rn~nclnl whose t.:orr.:nBrC:ll
blessings en~ ex~ct n rathe~ costly toll. Asbestos insuln-
t.ic.'n and f'~ct-.or~" '\ic~rJ~<.;"":rs exr;uscQ to l'lea-...';l cc~n.cBrlt!'nt.l c->r:s of
asbestos fiber over orolonoed periods hav0 suffnrod eev~statina
consequences.
'I'll(-!Y
n r c.jO
V.i..!atec. \>'1-tn~ ....
-....
,. .,.
,;;:n
lila.n:u' n:;ly
hJI .gn.o.
lI n -
- ...
cidcnce of ClS})estosis, \~'ilic:-! produces a eli ff\Jse fii):ro!;is 0 f t .~.~e 10.-..<.... ,'_" l U.~z---:;., o-""-' .1.:.".-.n':~:; r... c;..:~J,.r.....~t,.... -..... .'..."..'~".'..."..~~ o-J ""<'.. n (....,.. .r.....,.--e ."td"c';"-'..';" ..1.-,1.;.,"-~~.,-;:;..
cancer of the linin:.; of the l~fH.;J c:'H.l D.bcior~.en, ncsc.'>tiwlior.,a.
The rate};_ Clf l\~ng :::al~ccx- a~0 ~>:trac,l.""<1in,~rl") high eEjl:;~c:iH11)'
a~on? asbestc? workers wh? nra s~?~crs, indicating tha syner-
gJ.stJ.c potentJ..o.l of the l"tlnt::=n!l !'l.D~r.
Ahc nc-dicnl c::'\~~ ~.(!l1cc~ is illdnfil"li to C'.:S to \.!li\1 asbest.;:Js is
r~r~i~lO~P..J:"~1r:. ,_..,itl"l 't!!l.!":!t'-! tl)E.?Clries in \"(j~l'...'{~: {l) Tl:8 fi't;t~~r-s ~')ne~
l...l~!J9.3i:-e{-t:. <)?:... l .lLn~..L c!:'l s~t. n.s ~ c:ont1 .r:ous p:--~}"S~t ..c~~l J .l:":.l"":!.t~r1t, ~ n~~U\'=1 !1!)
<I L0m~r &fLer 20 to ~o yc~r~; t2J ~no r1tlCrG conL~1n d~rcinn;~~=
such. Cl.S h~n7.~(a)py::.<.::rH~; (3) ;-'.ibcfn;nccur.n:1<i.Le in t.hc ltmg unci.
r0m~) n ir!u;,:/bilizcd a~ "~sbc!->t.os b.odies" ..vhicn ca.u~e caJ1ccr UFNI
di:.int':p:at.ion.
-
Sibilarly, while the adverse effect of prolonged exposure
to h~fl ..J)!" c.:>nccr.it~r.:ations of c.Hl.,cstos i s clc{l~~ <.tocu.r:;en.ted, tflr~
medical data is distu~bingly vnqrt~ .~s to the results of lons-
t<.:rr~ ~;.;pos"Ure to l<..,~('"'a!lC1 17todcr.ai:c~- cozlce-nt::utic>l1S. !io:r is there n. clc.!ar d.n~3~~---tirr,~ relatip!:st:ip fo_r _ci/~:-~Dst:re t..c) :heo,\~" concG:ni:r-:tio;~s.. !n s})ort:, an \'"i t11 ;;"t:-11}1 -{">tllei en.vironDc:it~tl cor1t~rnin;:z1~,7.~,
t-l-10 }TUblir..; 11a~~ c!is-::o\~Gred t<)o lat~ thi':t BH1,estos is pot~cntially dan;erous and too little of the extent cf that e1reat.
L:
But t\w depr-cssi;lg f<"i.cts arc agreed '-"rx::m~ That millim-,s o!
~~-ericans ~.rc llt:..r-;:l~r to contuin "as!)cs't.c.)::; })odiesn in t.h~!:i.r lt'ln:;s
and tha~ -Yll-,'""'' Y"G,E:="""'-'~ ie..t.:i\'"'lv 'nr;~<!'-;t-""'"t--,,o::h,.st-os O''C"'" 1
J
_ . . . _ ........,._.
-
; ....-
, ___
_.......
Joo.. . , . _
..... - _ . . . . . . . . . . ,~
~,...........
.....
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..1. . . . . . . . . . . ~ ~~....--
ible~ 'l~hat i!>, ti10 qu~~lit.ias of ihJral;:ility a. r1d of l"'(!S1..st.urlCS to
no.:rT:1:J.l c'h<.:!:-Jical ?..1~tl r;h)~SiC:~2l St.ress_, "'.'"}:i~;h r:-.a}~e dSb(.~St,.:()H !{U-::h ~
col-:-:.raercia.l success~ !"(~~ld~:r it. pC'tr!n.'ci c:l~y c!l:~nsc}~cus to prese-nt
and future gonera -::i ens bG:c-al~>c cf the tcndc:ncy of the filn:~rs
t.o acct::_r;nJlatc in tt"t8 at. 1n~spbE-::.c anti ill the ll:l.ng-s.
FMSI 03076
;~-~~~~~~-.?.
-..-_ :'_.-:-~~- -_:---:-.-:-~7---~- ~,......:.-:::., :.~-~y~r~;T_~;;;:-,"1.~:~~~~-~?f-~~f:-T}_:-;-~-,T~-: ~T ~ll~ <
_,
-- .
;.'-.. ;,!~---~~1- {'-
-~.;,_:~~-~;:~,~ j_~LcL~_.;,i/;.j;:.i~;"_;:;::~i, ;. ,.:~,-~;~;z;0_, "~+;~:;;o,;~u ~,i.::,,"-;;.c~:c1J_::;! ~i~{Hi:JinD ~ il~~~ ~i it~ L; 1;:
''
~- ...... - ~
., .. .
the need to cxo lore und, p0-rhu.ps, to _adopt controlr; !or t!"H~
significant ~ontr1butors to a swelling volm~~ of asbnctos fiber
in our air ....oulc.1 consti t.ute a foolis~ cor;,plo.c>:!ncy.
'l'o this end, the suaq(~:;tcd n~t~ulu.tions ~:o;.,_ld identify
these "significnnt contr.ib'-'.tors" O:!S the CO:r:'..'7l'::'rciu.l \lSC of
asbest.os in cons t.ruction ;.:ol-k; the demoli tio:'l of a~;hc!_;-t_og contnining struc-tures; the :n:~.nufnct.u:r.ing unl1 processing of asbcstos-cont<;.ining produGt:s < tiH"! t:cansporlalion of certain asbestos-containj.ng products; the dispos~l of asbestos-containins wu.st.e: and the use of asbestos in the br.<~lka;~ of millions of vehicles.
Part II wouln impose seve.~ral gcnerf!.l requirem~mts u;;>on all
commercial construction, repuir, altG:r.:!tion, ool'lolition,
manufacturing or proc:ess.lng ac:tivi ty from ....-hich asbr.:s toG i iber is dischurged into the environment. The persons responsible for such act:hiity must obt3in a permit from th<.~ :;?1.. rhe. permit system \'iill serve to prod,.u:c th~ advanced .ssarrancc nf. comnlivnc:c with the applicable control regulnt:iom; and \lill thus reduce t.hc
cost and burden of in-the-field enforcement.
Jn addition these. corr:r;;erci ~1 ncti vi tir:s .\'ould have to
provir.'.G! f~ci l i ties to pr<~V<~nt the n?:~tovu.l ot asncr;tos :t.:l.bers
ft'oJa t:h& site o~ Sl,;Gh acti \"i t.y on th~ clothing of enp loy(!cs.
Indeed, t.his po:;t~s z. r<lthcr ne\... concc,pt of zd~: pollu~jon cont:rol.
.j't10f;!..'! ~.-.,n.O !'!Zi.'..YC, diC!"3. f!:'':.'!:i l'..!.!l'J ~!. ~ :!~'...~-'1 :. ~;- .i.2H.~~~~ .T-.otJ J.;y j 'Hi~ r ~:\...~ ..::;c7:
associ~.t.:i.on to a;~ <'<Sbcsto:> ,Jorkt?l." mn.y be non:rful procJf of the
nce:!d for nov-elty.
,'
Finu.lly, P.;;.rt II \'<O\ld provide for caretu.l waste di~pcH~al
proccdu.1c~, an \.zind-bJ.o;,n n:ruse ."heu.ps m;d scr4:tp p~ lc~ cont.rihut.o t.o the volume of o.sht!:>tos f~ber ~n ou1~ a:u.-. The ~f:!n.i.c stcu:; for cont.J:"Ol eliminate ~ny c>:cuse for snch d~n9crou:::1~ slopp~'
Part III would prohibit tho ~praying of asbestos-contain\ng insulation and fi=e~rooiing. Ex~~riencc h~s indicsted th~C pYoced:~<ral safegt~an3!:t are inade~rl;;:.te and their <-mforc~:>mcnt is an ovc~ta-:d ng ;:nu:d~n. Chj cago has banned ;;pray usbosto!;.,. and New York city am~ Phi.lauelphia arc_ ccmsickring doin9 so.
Procedural snfecuards designed to rcduc~ fiber eR1ss10ns would be required to .. spray non-asbestos insulation. '1'!1c bioloc;icv.l effects oi thc:,;e fibers i r~ un~no.~n. Prudcnc-:) \:ould scem to dictate reasonable efforts to soften the Dntential future blow from spray fiber aspiring to H!'ibestos' status.
at require that asbcstoc construction producls be so in~ta!led as to pruclude th~ e~ission of fiber into the circulating air.
-2-
FMSI 03077
-, "~ ~
- -~-r :~--~~T::-~7'~-~~-:-~:::---- _>:,_.,..-~~::--::-o~:~-~,:-'" .......-~.:-::r...,_...._~...-7<:..__~_ ....,..-r~-.,._,~7.-. ~---_~~,~-~~: -~ :~_,-~,.~~-;:~-f: ~ :-- ::-;~ .-_7~-~ ;::~:-:7'T~~~T~~:;
-. .~; .:.- ..L;::.:~:...:.. "-._1_d<~_ -~..-:}.- -.....>-~- ._:~-~ 'i,-_."'_,_;;_~:: J~<::.-.:"".,_.:;{:..~.--.,U::v-:-:;;:.~.n>.~:_..-.:.:....:..~-----..c:.~..-~-.L\:-:.~-;-.....:.<.......:-:..:_..~..:=.. _:;.:. ~:-. -.~' ..-..:_.:.~.--~..=.-.,.,...:<:.~<.~-~~.~::~'~--.-'.:-~_~;_.~-:i~-._~---~-:. -~--.;. -~,~:-~ 1~--~-~--_:-.--~-~ ~_; ~..: . :-: ~ 't '
vPart
o::--~pr.cssr.~s,
ironically, ,;hu.t may be a key reason
for
benning spray a~bcstos. It would rcqtiira that procedural safe-
guards be l'Ur!1t~c:d in ord::!::r to C.c~r:*!olisl1 u: s~ruct.urc~ \:!~o~;t~ cicc;tr\lcti_{>n
.\'>'ould othcr.,'isc- CX?OSC r1cnbG!:S of the pu:,lic t:.o .:tsbt~stos Ei.hcr.
Clouds of c.iu~;:t. d:rr.~ oft.(!:! ral!;cd by cJer.1olit.ion ""Tod'. The f<lcts
thut gre<~t nur:-2~><.?!:"3 of r;s::-:scns m=ty be.! cxnosc-::1 to thi~~ t1'..!st in urban areas ana that ~h; pbst-wnr gener;tio~ of hi;h-riscs
'.tt'ere the first Lt~i_lUir~~;::; 'to u;;c ~s})cstos i:1sulation cxtt2nsi~.rel)"
Spf!ak in favor of so:~c such regulution.
Part VI su('c;-ests i\n er:.issio:1 r;ttmdard for :nnnufacturcrs of as}Jeeto[; :J)r.'t)~4itl~t::!. '111n staJ1c~:il.-d is beli<..'!')ccl t c.:> be \~i thin
the Cttpture e"f ficicncy of bagbou~;c. fil U.-.:ttion, 'l'hc n:ronoscd
boundary stand<:-<r~ is thought to hi'> a r.\0t!1od for pn:v~ntlng
dilution of.exhaust gases.
.'.
The st,"l.ncard \.;Ou.ld measure. only
fib<;n;
long.:n
than
fi v~ microns.
The justi:fici.tion for this seer:lt; to be t:h.: admini!.>tr<~t.ivc con-
venience of uvoidin~ dif~iculties in ~easurin~ fib~rs fro~
.5 to fiv~ micl'~ons in lP.ns-;th. r112!dic<~.l evitkncc hv.s i~1dicatc~
that the very sr.~all fib-?rs :r:no.:, be.~. tJvJ rnost d<mgcrou:;. J'\nd
the mara ";ill seek extensive evid~nc<~ on t:1is point.
c:r_?f!Yt \1~1. "~:{>VlO prc~hi!)i t t:~~e ;:~(!
j):~r:}~: linin~t . in ~'c~i ~~cs
manuracturco a:tc~ January 1, 197~ ana solu ~or usc 1n Ill1no1s.
_ If brake l ininc; O.ccorap~si lion t~'3.t.s <>s;:::;:slos !:i}:cr, thr;m thr:> trementlot~s nu'i:-1~n")! c>~ v:.~'hielc!s "'ll!:. irtg il.Sbf'stc.-:;:~, 1!!.nd t:l1o :i.rrlr,ri':.c~:- .. ic~litv.; o~ cor~t:l"'ollin~~ these f!t.u~:t:=-<.)\JS sr;-t;J.ll e.rr.iseic):l s-~uf-c:('!S \'i'<;'u~d. ;pp.:ar to ~pc~k -to ....'1~ nceC. f.7~ Zl. p:rodu~t ?an. 'l'i~<;. p::o-
h1b1t1on 1s cnrQ:ully word2~ to avo~a the n?cess1tv of ~1tt1ns "\t<?.hicles produce::"l p~io!. to 19 75 .d t.h non-:::sbestos br<<k~!';. ! t
is C(Jn t. cr.tpli'~. te-(1 that: the ba11 ~;ill rlt~C(!S!~; ito t.c c~osiqr1 c:laJ"!'JC!!;, prob<tbly to disc br~}~c!~, and i t is thou~;ht t~!:d: requlrin:;; t::O.:~ invid.ual \.'1eh.ic!l <! o~~'ner tc> u.n<."ier~ro tl1i t; (!X!.)C!1SC is j.!1re ~;.sc~n~lLllf! .. The ti~c lag o! over three years is thought to be su!ficienL for vehicle rnanufaGturcrs to acco~~15sh any necessary 6esi~n changes.
-3-
'
FMSI 03078
~r
::::r . , ' .--:- L
~ ;-':""= -:{-:~ :~~ -~-~-- >~-~--.'-~~-~-~-~~~ ~: ~-~<~
. ~~ =~
_L)'O..~.:~..~- ~,..;_~~.--=..~ ~:--~- ---~--~ ._.~:--:.5. :..~~~-' ~~ ~-- -.;;..~-:.-~:~-~~:.~-- -~2.~:~~~'""-~'-'-::"';~~~.;-...ii..~.:.~_:-~;....-..=-i:.:...:_l __;_~_:-:.~~;~u_-,_ -. ~~~-..:~-~~;:2-l.-~~~ :.;~-;.,=~~~-- -~~-:;/
.
Part 1.:
Part II: :Part III
Part VI Part VII
Proposed Regulation Only
--.L. ~.- ~~-nc 19,?.~BS'',,.9,Cllhl.'. j,t-( ". ~ox1c
v . .~.~>...:. ..l~:.'S
l\SBESTOS: SPRi-"1Y INSliJ.,i\'I'lO~'i
T__a.._b._le of Contents
Introduction
101. huthority 102. Policv 103. Definitions
201. Permit 202. Rc:;;oval of ];.Shr!Stos from clothint_;
203. Waste disposal
Snrav Fireproofing and InE.ulation............. ..._..'<'".,_,___.., __
_~
301.
Spray asbestos pr~1ihitcd
.. - ,. ..
l~\.J}~#O:"lJ..Jt~:~t .. ,).:")
.
~j..tl rl~
~ - - - . . . lt . .! - . ..\...1;40,:,UJ~U"-''-"Il
Col ; on z, 1 - "1" - -'.,~- ~-u,...' ~O''.. A~ - - ....... '"--'--... .. I .. \...~. ..... ..,A. ... "
40J.. Er1closurc:;
1.02. Preclude b~poGure to circulnLing air
Demol.; t:.ior1
SOl. 1\ecessarv and. pr-:tct.icnblc snf.c..!gunrt1s
502. Ccssatio; of demolition work.
- 601. 602.
603.
I~m~ :-;s :ion ;-:t<Jndard; concentrn ticn at bounrJarJ
?roces3 W<:l.Ler Waste sludge dis?osal
iOl.- Trunsnort~t:ion
702. nrakc.linint,!
FMSI 03079
~~""~:--:~"7"'"''-:'-:'__,..-::;.~....,....:--~.'""'"'""""""~-::o~,...,_~................=-:-.,...-:'"---"""":-"'--:-~"..- ._ ..._,~~ .....-...-;!....
~ '-.... . ~-..~"- .; ~.
~-:~.-..~~ ;._.__:::_~. -~..: ...... ~~u.-:... _- . ' . ,: -~-::._-.::_:.;,~~.~----~:.::...~:---~- -~;. . -. -:. :........:........"~-0..:...;. ~:~-6>~-.~:~~7-~.i;:r,-,:_~-.:...;-~1~. J:.~;.~-~..~,. "i.:::.<~~~i,i;_{.; ~;;i
PARi' X: J!J'l'RODOC'!'I ON
101. Autnorit.v
Pursuant to the <:!.Uthod.ty in Sections 9, 10 nnd 13 of the Environmcnt.al Pz.-otC>ct. i.on il.ct v.hich t~mpm-.-t~r thn lloaru to aclopt
rcgul<,tions f(nhi ddin:; the ~ s0.lc,, offer; o~ usc for reasons of air l):Jll ut.it;~1 con. t.::-ol 'l c;f anv art iclc, fl11.:1 t:c.) set ., standar<.lf; spc.cl~:oing the wu.;.:i~n.H:l 2rr~cr~'\':1tf# or c:~O!lC~!ltrations of v:trious cont.:tmin<mts th~>t may be discn<:<rgsd into the atmosph0~e 1 '; ~->.nd to st~t stand:;~ds for t.h! issu:..:1cc of pcrr:ti ts for thn operation of any cqu.ip::~cr.t or f<>ciJity capabjc of <.:eu~;i.n~ or contributing
to air pollulion; ~lnd to p~Omlll:-;rtt.e ucon.ciit:ic~n.s :::-e9ar(ling tl1c~ ....
use of any c.r.ticle det.err:d ned by t.he noan1 to co~1st.i tutl~ <>n air pollution h~zard"; end to Hd~?t effluent stRnd~rds limiting the a.nounts of ..::ont.e1~1lnc.nts UE<'.:. n.:-..y be disch::tr(~!ed into the W<it.cr
of Illinois, the Bonrd adopts the following rules and regulations:
102. PoJicv
It is thr~ r:-u1rJosc of the General 7\.G!.;c~:\bly in ?<C.:opting the Envi:ro:nr:~entl Protection Act to m2.int:ain a;H.l enhance: tiw p~l.ity
of tho air ~nd water of Illinois in order Lo protect health,
\lcl:f.arl... ~;1(1 tl1c~ q~1ali.:,.._.f o ll.!.t~ . . .\cr.::c,tdi_n,.;l.'/, j_t:. j_s hcreD).
\.1t;.i.,~"!J_,~.;Ht..a~ L~lt~~L t~~n: t.lJ.~....(J,it-1:0~.-~,:;.~
, , r\-~;~._.\--~~nJ\j~_.
.r.~~s~-'":--.:,,_ :-~it:-"1
in-t:o th~ envircn;-;,e!1t 2:1(1s to sc;c:cly cnc:,~n~;er tbG:o l;ublic 1v~o.l th
and \~'~ 1 f ere ~.t~l c1 t :-~~ t tl'; c 1JDC{)r'i t~-c} 1}. cd spr-:3 y i ng o; f. ;_;)Bl~- con t..:-"li n in-~ matorials unrcosonnbly interfer~s with the enjoyrnant of life and
property.
lt is the purpo5(~ of th-::~sc icg-u.lvtions to control tho an:z.nmt. of v.f:,besto;;; fiber released into t.h(~ cnviron;.;cnt fron the r.-w.jor
sourc~s o~ ernissi?n S~~h. contro~ is. nece~s~ry not.oryly to~
protect tnor:o r:::~r:u.H~r.s o:: tne pt!hl.L(~ ...,,:10 arc.:, 1n pro::l;~u ty to haavy
conc<mtrations of usbcstos !'ibcr. but nlso to snh!'-~U.~l-d the h.:;:nllh
c.. ... ._':.:-...... ,...;> '""'"" :.:.- c ... . c.ou .+h,-,O .f.....
f'~L'I"''r"t'."i
..... L_..;....,._
,~.-"-'~l....l....-...--.
..
~,"'-~ort"'
.:: .. (....J..,. :-;;>
-:~.~J-'~y~r-../"!;,,_.l"~io.(-,,::"";-.~;.
Q"~!"'\.~'_-~:1"' ..
~~.~
t,..).:~.~
~,..,1
... ., .......
l"~-.~,
'..:.:,."~-..
r..;-~::
asb~h.;tcs fiber 'h'hich co:1 be to>:ic nd \!h5.ch "!:ends to be cm:mlnlive
bo !h {)' i\ t'l" 'n-..1
..1,. "
t-})r~
- .. _
u<>f-._....,~'I....'-}~.~l'~t:.-}'t-'>l""'""" ;:-,r;',jv.'"""l",
J. - .
f u-~t'c-;:~._n ',. ;o''J',~.J'
l7her.e hec.lth can be pr<-tectGr3 .by t.he ~::}option of an (mission
stur1clarc1. or~ c)f })rocud.ur~1. safc~g.!..H:ir.t.~.s, st.<ch u courr;~~ 11as })t"!cn
p\lrs uctl. In tl1o:1c~ ins t~nces \,11f=!l:":! !""et_; t.Y~ i c t.ic>!1 is tlnf eu.it1l c:
been use of the trcr.tcn,3ou~; nmn1)<.~r o:: sr:-.c~J.l, uncont:roll<ibl c cni s;;i.on
S(HJr-ces Un!tomctive)or be::<l'..1se of i::he U:)D:>i.<cll n<'!t:vrc of tho
erni~sion source (spruy fiSbcstos ilt construction sites) a product
ban hu.s been :;:ccort.<'!d to. Thf!SQ p~ohibi_ t: ions rwve bocn m<-!.de ''li!:_J::l
- -J
f-.
-t-ll
J: C011Sic1er a t
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:
i
c
;
l1
-
gi \-:~_.t_o__thc_~~C"tl.l_abl_Q_A_~ i;~}:!'l.D. t i \"e
--
1~13 tt~ri n 1 s.,
It i s al!;rJ t~!f! purr~osc of ll1c:~~c~ l"f!r.JU1atic--,n!; t:() ro~1'tl~..:e tl-ic e!ni ~;i"; .i.on of :-1on- ~sbe:~.; t_C".~s p~l~tic'tllc te f roin f;pt-a/- f i '~cpro-:.')6._~1~J cJ.nc1
FMSI 03080
---:-..!..,..""'C
,.
~j.,,,~ ,..,:.;. ~~<;_~~-H.! .: ~ , .~..-~~~- ::-~~~_,-. ~.-~:~c_:~~~..i.~-- ~~-:-~;~c.::~.:~~:,.....,::..::.~ ~;~.~,~~~~..-~~~-~b~:..-~~~-,.L....-;,_,-._~-~ <.:~-~~1~;...~~,:._~~:..::~-:.::_L~~~ ~-~~.~-~-L. .:~.l.~ -~~: :. ~ .:..-~~
insulation. To prot.:ct v.gainsl. these er:1issionH 1 the biologicnl effects of \lhich il.re t:nknown, proct~tiutal sa.fegu<~rcs f!.v.ve bcH?n
enact:cd.
103.: 2_efinitions
Agency
The Illi naif; Environmc~ntal Protcct.ion Agency
AGbcstos
~.ny fiber or any mixtu,~c containing fiber of
hydrated silicate mineral, which, on the basis
of its crvstallinc structure, falls into one of
two categories:
(l) pyroxenes - chry.sot).lc fib>n;
(2) amphiboles - crocicqlite, usosite, trcmolite, attinolytc or anthophylite fiber.
Board
The Pollution Control Board of Illinois.
Corr..mercial
t~ctivity
Any nctivit.y dont? for hire or having financial profit a~ a pri~ary aim.
Debris
AsbustoR~contaihing wast~ produce~ by tho
,.-.r . .t..l~h; __,f.J.t.i(,~:~
~ ~:_.r.u..::L...:.!t'!.
Spraying
The Pl,'u?uma.tic. <:ppfic~tU.on o~: n\atel".i.al used for f:u:-c:proof:l-ng .or ln!~;ul et1 on.
Any ashcst0s containing 1.1c:.ttor \ihich has b<?en or is intended t.o. . be discarded.
l~o corn<nerc:ial o.ctivi t.v I not." othendse here.i.naft.C!l." t.'>rOh ihi ted, itl\'olvinq t;lt-"! U.isc110.l"qt:~ of. asbeston fihc-c i:"1t() t.bc cn-r\~ii-on8ent
fro Y"D'"''rtht""'-COl1s!-~-u-~l o''- n1+-c,-r.+10'"i". .. ....._,_
- -
-
4
...L ... .I ,
.... "" .,. - \.-
4 .I I
- __. J."' --- ~
O'~"
'"~Pr",,-,J.~-1,,.-
""' - ._
oL . . _ - \.F l .I.
..", ''."L.
."..'!
')'"~,-'""..... C-
t-c:,s ..tu r-~..-.-"'
\,.,.,.}y--
f-l-o--~ ~"'- .,.__,~....., '-r..'.I.I...).<.Q..'.' (.,:~..f"...--~'...l,...--'(' 0"-"'
~.!~'';~-"t_\..-'.I ;.~.- \,!;...l.
U~i ~..1......
,-J
... .
'1-
.1. '::.
'\..'.o...f..".,i1 C~1)""S__:-_
C"-"1-"~ :~""! ~~ ,~.... ~).. -"~~
proctuc.:ts, f;hall b(! coacmct<?a un.les.s tne pen;on or cn'\:l t:';:tn cnar.go
-or such-ac;t.ivity complies ":ith fh<::!: follo,dng requlations:
201. '
A permit shall be obtained fro~ tho Agency Lo engage in such
act.i \ 1i t~1 Bcfo:t~c obte1i :n ing s t~cl) p-ernli t, tl1.:;! a~,r-11 i Cdnt s!ta 11.
demonstrate compliance with the following s~feguards:
(a} The dcsignetion of peruonncl to exercise fulltirnc sut)cr\tist)ry a.ut~ori ty o .lc!;.- ~.11. H!>l-'CCtp!; o! t1;c act.i vi tv fr<>m ;,. !t;it.~h tJ;e releas8 of asl)c~t;:os fi1)~_:r i:~t:o t:!~1Q erl\."irc,nment cou!.d result, :in n\lCn a l7l;::nner as to i'nsur8 ce>J.:p1i.:mce
-2-
FMSJ 03081
with th~ pertin0nt asb::::stos control regul'~ tions.
(b} 'l'hat ertch c;:tt->loyc~ en~1u<JDd. in such activity hns completed or will co~plcto a satisfActory cours0 of in~truc tion on the p:)te:1ti~.l h<-:za::cd$ of e:>~pos\:re to osbl.~stof; fiber incJ.ur"i:i. r:~; the precautions. th<1.t i:\ust bo:..~ ohr;C'!rveC: to prevent or: restrict the disp<?-:::-sion of asbestos fiber into the~ environ-
ment.
(c} That such additionnl safeguards as are hcrcinHftcr specific~lly required and such precautions ~on~istcnt with
the purpo:;~ o- these: r(;!gula tions ns tho l\qcncv d~t"!ms nsc:es-
sary under the circumslnnccs shall be complied with.
202.
Facilition shall be provided and procedures insLituted and
suporvi~ed th~t prevent the rc~ovHl of asbestos-contoining material
from the si t.c;! on the cloti1ing of. cnployccs.
203.
A~best:os-cont.:t~n~ris; \oJ&st:cs. s!H't.~l ~c iml:-~?dj ately vac:uurned or othenn.se collected \mere vacur-n.nc; l.s 1mp~')ss:tble, and s:-.:~ 11 be placed in a container resistant to Learing or breaking u~der normal hi:in6.lil19 conc1i tio;1s, ,,;hich ~l1_all be tis_:htJ.y nr:aled i"tncJ clc~u r1 y marked as contHining ~sbcstos ~aste. Such cont~incrG R~al~ be placna dir~ctly uoon a vehicle for diGposal by buri~l ~t ~n ap-
provc'l si t.e.
Section 20 3 .sha11 1~ot <'tr'PlY t/l t.hc c!e:;o:-Jl:i. tion of < !;t.nH.:ttnr~,
e.;:cc:pt c.:~; providc;:1 :i.n S~ction 501. (<l),. {d) Dnd {c) e>r to the
d ~spoo-] ... . ., "' .
01J:.'
-,~.~J. ..,.~;,-....~..~...
,,.,,,"..".",t(-
(.='"...r....e'1"-"'.'. ,'~".' ".,
1')..'_ -0",..~.. o...-.,,::-;
J.n
.~.......... c ....... ~~- o n
6"""~~'
PJ-.R'!' III: SPRhY FI~?_r~oor:WG l>.;~D 1 ?WUL!>.'J'JON
301. 302.
; '-
Non-asbestos p~rticulnta rn~(te=
..Pro ~ "
-&,._......;..~1~~_.
c
7
h
,
.
,
l
l
no.-',-_ .-_r._,._.
~c-,~,1-v~;-:-:."-''~ . .,,1-l .(.,..:,..,
tukcn:
used for insulation or firethe following procedures arG
{n) B~fore the start of" sprnyin:_:~ op12ra tions, ;;; 11 n oor
areas shnll be swept clE:<,TI ."'ln0 clc<n~<!d of all objects, material ~1r1<:l ecjtlit-')nicnt ot!1::.r tl1t~li tl1r:.t~ employed i:-1 tl1~ at.-'li)licat.ion _of t..1l<! fi!)er-co~-itai:-1 ir!~; rnnteriill, c1r, in the a. 1 t!~':-na
ti\1C, all su.ch objc::cts, ra~t.eriz-tl ilnc1 en~J.ip;~:t.~rlt~ s:1alJ 1)c
covered ,)ith pla.~;t.ic or pl<<st.ic-coatcd t<;Jpeulil~s.
(b) r.rh<? entire floo::. or area to be sprayN; sh~ll be enclos:::-<cl ".d t:h pl.-.stic or pl"-.stic-co~ted t.~:::p:-:~\11 i r:~; in a tna11r1r!r \O::lic11 s11all l)r2~lt4.d3 the esct~pc; r.)f. fibe.:-cc)ntui!Jinq
material from the enclosure. All interior ope;: a~eas such as elevator shHfts and stai~wcllG shall be enclosed in a ~~n ncr whicll sh~ll prevent t~e escape of Iibcr-conL~ining
-3-
FMSl 03082
~-. ;y ___.., -- .... --::--:_;; ..............---..,-~_~_""".;:;.~=--......-~~--~--~~~;~:~ .. ~--;~-~~-~-:-:..~-~- .::_~,_.- -~-~ ~
:-- .~-
' .. ' .;. : _:. :..- :
~... ~- ...~- ;_:.._;-~-~- -~:, _;,_...:;:.;.,_.:...:;...;;__:..i..'-~:2.-:..:.i....~~;.....:..--:.:..:._:.;_.:..=~..:.-:.:....:....: -~:., ..:-.:.-.a."':...:~'-.-:.. ,_-~-.;:_..:~- .:-.......~;:.... ..i:;:=..-~::
~ --
rnatc~isl !rom the ~orking nrc~. ~stac~ Gff~ct" of the shafts~ st~irvells and cornpnr~ble sp~ccs shall be considbred in
providing proper enclosures.
(c). Regnrdlcs~ of adherence to the stated control practices, any ~isible emission o fiber-contai~ing materials
beyond the buildingpurimetcr will be considered a violation.
{d) In caHe of visible c~ission of fibrous material
from the constru~_~t.io~' sitG, i:-;-cnodiat.c stcos sha} 1 be taken to cause the cessation of such eDis~ions by either
effective CtJnt:r()]. :-aer.tsu:.-s (")r "tlork st.O?IJRgc at t!1e so~rco
of the emis~ions. 'l'hcrc shall then be irmnediatc and com-
plete cleanup of all material that has cKcaped tha const~uc-
tion 5itc, a~1d r;,ca.sur(:!; s:'1nl1 be taken lhttt Hill insure
;""
that no further dispersal of any fibrous material into the
atmosphcl;'"C can occur.
(e) The en~ire sprayed ar~a, all ledqes and surfocoa inch~di ng tnrp<tul:i.!"J!j \d thin tht:! enclosure srw.ll be tho1-ough1y vactnim<=d upo:-. corr<pletion of the sp:tAy:i.ng opc:rLttio:"l and immcu ietely before the er-1Closi.:re is dis.;;:a!"lt.lod. 'l'hc! vacuurn clealler sl1~ll co!ltrtin rt st~rC".1 11S, sinslP--r;c.:r:\1ice, ,1.isr)os~~.})le innc::~ b~~~ o i Uti~-t:t:iJJ c Ltt!i:.!.-!.t-J.i~.l ,iilic:l s11u:i..L i .\e rcrnO'lt!W i:rt,!!t
the vac:t~ttl'1 clE:an ...~r and tio:;htJ.y .sei.~lec1. 'fhc bag s;'lall th<:>n ho plnc&d in ~ ccnt~incr ~~d di~~o~cd c! =t ~n ~pprc~o~ ~itc in accordance with Section 203.
(f) All areas u~ed fqr opening baqs containing .fibrous m<itcrial or the changing of hoppc!rs shc.ll be
enclosed so as to pYevent th~ escape of such material from . the ir.',lucciatc area in v;hich !;uch ~ctivlty occ.a:s.
{g) l'>ny plenur.o or othti.;:;- _f;t:ructt~rc coatc~d \'i'ith or containing fibrous insulv.t.io1i ~:.nd il_sc,cj in the! ci reu1at:ion of
air in a building shflll be t1w:cou~~hly cle<tned of n.ll <"kbris
c.nd \iaste insulatio:1. All upplic6 fihcr-containinq in!;ulation
\-titl'litl a olel1ili:"t or duct s11.all. be cr>at0d 'iith u seulul)t
which precludcr5 c::.:posure of the fiber-contnining 1:-.;;.:. tcrial
to the circulating air.
-.',
401.
{a) The cut.t.-i n::.;, trimming, .f:i. ::.ting or stripping of asbest.os-
containinq material in the construction, a) tt!:r-at.ion n:!:" rel)ili!:" of a stru~turc ~hich is dono Ht the site of sue~ structure shall
b~ conducted within ~ ~p~cinl enc~os~rc designed to preclude the
cscc;.l')E! of usb&st-l.-,S f:.iher frora the i_rn.rr~cdiate are~t of s1.1ch cncJ osul"f: 4
(b} Th~:=- rr~8c11Z!.ni(:al exh:~nst-ir.Jn of dugt fror.l su~:1 er1clc-Jsut.. e to th2 ~n;D)ient. air i s 1--,ro~~i1)iteci u~1.less stl~}l e}~llflUSt syste-m is e~uipped with a f~bric filter for du~t collection.
' -4-
FMS\ 03083
-.
402. Ar-;bc~s tos-cor~t<!inin-;r J.:n te:::inl <:!ppli (d in the cons trt<ction, alteru.tio:~ or rcp<:dr of n ~;t.:ructur.:.! s!1all 'be co;~tcd >:ii:h SE!ttli'lnt., [>rO'..:!'i det.1 \,~i th a CO''./C:!r or i:1itSrlJ. O(} i~l ~;Ol~{~ otl1er lr\rt1'H"l0.:r.- 5~-i a!.; to prccl\.1de cxpoz~urc of the .::.sbcsto::i fib~:::: to the circu.lotin9 air.
SOl.
\'ihe:!:e tho l~i::;k of public expc,zu:J:'c to asbestos fibar from ~e dislodging of Dsbostos-contain!ng rnaterinls is present, no demolition of u struct'..:l... o shall b0 il'!i ti .:;. tecJ 1.1nJ (!SS ~ll sa faguards necessary and practicable to rcQuco Ul~ emission of dust are taken.
1
such procech1n.!r. shall include, but are not necessaxily limited to:
, (a) BoilE'.r& anc'l pipes inf.;u:!.ated \lith asbc:st.cs-containing material shnll be wetted and stri9ped before toppling of ~alls is bocun. This procedure ~hnll Lo followed, whc~c practicable: as to all oth~r asb2stos-linoa surfaces. Such
asbestos ).;'f-!!;t.e s}-J~ll l>e ir:c~1eO.it~tcJ~l !)a.'J~I0(1 tlnd C.:l_S!)OSt~U of
in accordance with Section 203.
(b) Denolition by toppling of walls is prohibited
(.~X,r_!~J:-l\..:. V.'l.;..:}!l!! -.r:'p +_... ,:~~ ":.tt~ol i- ~!.. .. !"'~ tr\:,:..;.-; ~~j: :.~H- 7-:;.-;:~i-.~:"~ ~,:; !.. ~~7~
the r)c~rn,it Cj:C~Lnt-Gd fo!. de;;,olif..:i<._)j) C) ti'iC~t St:r'D_C::.~lrU.
(c) Before the ck:molition o nnv section of the st.ruct.lln~, ~dcquatc wetting to suppress._thc dust ~hall be employe~.
(d) ;>.sbest.o!:;-contuining <1c:brl.s sh;-J.ll not b~ dropped or throvt"n fl-oP-1 ~nv floor. but :;}~::.:.11 l){~ tr,!.nsportc:~a }:>'," U~l!~;t: .....
tig1lt: chut.r::G or b\1.cl~(!'t~;. r~sbest(~s-contn.i!"1inq Cc:}Jri~ in
V_..,l...._~, .,. , ~.. c-c-:
o-_r l~-)"~C"'..","".\.,.'..,..~....{....._s
s
~h... u-.1...'.
1 A
1w-..vn
Vc-:'o::r:;t\-.J::.~.-J.. c..-. -;.r..:~...n~,_1_,.,i .-..(e~..:....\,._.;~_~a
t.r.._.1
p,j_.....,_c.,_-.,.".~.~J\.t.(-..,,..t.!
dust dispersion ~t the point.o~ dischnrge.
(e) !~11 asbest.w_;-eo- ntu' .inin~~ debris sh.:'tll he thoroug!1ly
wet.t.ecl })cfo1c lc">ac1.i!1S into_ true.}~r;, ot1"1a:c ,.,ehicl8s t't C(~n-
- tainc!rs. Dtf!.-i 11g trans.l):_,r t sttc11 ,..:-as t.o S~)a lll,c~ c=~nc lose d. or
covered so ~9 to pravcnt dust dicpersion. ~sbcstos-containinq
dehr is sh<tll be dispo~:<:d by bi.n-ii:il C!.t \3.n approved site.
-
50 2.
In i.:hc c:vcnt usbcsto~-cor~ taining matter bcc:olacn ttir-hor!"lo
beyond the p=opcrty boundaries or ~n the ev2nt freezing t~npar
aturcs nrc~lude the usc of water for dust suoorcssion, dc~olilon work sh~ll cease until adequ~tc alternate Re~~urcs c~n be taken.
601.
(t-t) !-~o f.::!ct.C.,r."Y, ~:lan.t or cntA!l!J~ir;e ,,\..h.i~h (:n(]H<Jt":~! i11 the t):r.ocessil1~ or r~~::.~uf~ct.-ur 5 n; of t.~ny i:!~;:~cr~tc~s-cc.!f1tQin:l n!:.: pJ~o~i~ct f;h.c1ll Gi~tit ::-.0bestos fi1J:!r into ~h-:.~ ar:l1>it-:r!l D.i~~ i:-t c;..:cess of . 5 f ilJBl~ ~:>::~i:- cu1Jic cc.:1t.j hlC-:!t.f!:t~ of uir ~ 'l\1~c ar;'...1)j c.:n t
-5-
FMSI 03084
- ~--
---.-~~---;..,....._~--:_---r__ ::''~.,..L~-y.-~-.-;- "'7":-.._~~:':_~----~....,-.,...--.--
..
:-'~/!'c:--:--~'"""-..::~~-~~--;r-_-----~-;:.-~-~;.:.--=-;:~.~G--;"":,.~.o-- .-.::;---~-
_ ____..._...;....
___:_ _:.......
' -- -- ----~----W-
air quality nt tho buu~dary of sue~ factory, plant or enterprise shall not exceed .05 ~iber po~ cubic centimeter of .::1r.
(b) Only fibarc of 5 microns or greater in length
a 1e11gth to })~~~c: th rRtiu of 3 to 1 shall be counted.
(c) S<l!i1plinq !;:;.::11 b(~ dett:":rmi.ned bv the r:.~nbranc~ filter method \\'ith p.nse cont:c~st. mic:r.o~:;copy e.t .:30 X
magnifica t.ion.
602.
No water used in process1n~ or manufacturing ~~lich contains
concentr~tions o! nsbcsto~_fibe~ s~all be discharged into scwagu
\ syst.c1~1s or to thG ::aters o:- lll:<.ntns.
603.
Ku.stc slue~!<: cont.<li:lin~r u.sbesLos collected from sct.tlil'~g ponds
shall be enclosed during tr:;;,w;Fo~:t: end shall. be disposed by
burial at an approved site.;
701.
~~
.
1"~0 t>J.06 UC 1.: ~:~ iG}1 may '?!t~i t ~S}):.?- S t CS- f i1:>02- d l_~ l~ i ncJ 5. tf; ~ tt: tl t'i!i-~0~~~L!~~ z~~~: ~~ t=~~~P~~~~~ ~~~~~~ =~=~ p~8~~=~ ~= =~=!==~d such ~ r:;;;;~'ln ~:t .t\ s t.!";~ r~r-cclu.5e tJ-j,e (.:~~1i S S i:'..'l!1 0 f ~! s:)e!; tO!..~ !. i i)cr
into t:lv:: ~{~1bi0nt air .
i.n the L.::."'~t~:.e lir~ing c.) 'l~hicJos rn~r~tl
1975{ a;1C sc~lcJ for u~c in Illinois 1~
FMSI 03085
III.
\.
J~;stifictti:ion
~ . '
. . '-.
' { ...
This section \:as c!<~'.'elopcd to explJ.in t:ic: rationa1e for the
st~nda;-ds presN:ted in Section fr of this report. It 11ill not be
p)-.:::sentecl in the official pu0lication of the regulations. The
orjustification is given for this type standJ;'d and for each s~x:cific
stan~ard in the order they are presented in Section II.
.:
Ideally, national emission standards for asbestos 11ould be
es::c.b1ished on a concenti'ation basis re1uted to health effects ar.d
would provide an ample margin of protection to the public health
r.;ga;d1ess of the nun:ber of sources in a given geogn;phic area. There
ur<: :;wny practical considerations \Jhich pto:libit the establish:r.ent of a nwnerical standi1rd in the tin;e frc.~:;e estab1 ishcd by the Clean t'.i t fJ.ct of 1970. Foremost of thQse
Ti1is base is lacking from both th~ health-effects standpoint for non-
occupation.::l exposure and the emissions stcu~d;Joint:
The hazards of exposure to .asb2stos hcve Jcen C:etermined sufficient
to warrant establishment of a nctional standard relating to control of
otexposure. Determination of th~ level
exposur~ to be considered
saf2 has,been complicated .bY r.:&ny -1-C\ctors, not th2 least of \ihich has
t~ cccupational exposure and can~ot ~2 readily c~trapolated to non-
occupational levels.
Geu.use of the laro.c en1phasis c;1 occU,JC\ticnr11 1ev2ls of exposure o.nd
FMSI 03086
could bG.cvcTco:;e, soutce tesling cr:=oi'ts 1:ould h2.ve to be placGd in a :)osition of esL:I)lishing, rath2!' than ve:'ifyins a dab base. This I'.'O:Jld
hc a fon:;idub1e task C'Jen v!ith contr::.ctcd source tests and is unlikely
to generate a .sufficic11t base prior to prosulgation of the standard. A control practice approoch to reducing asbestos exposure levels
Offers a practical alternative to numerical cnission limits. 'The ;nainsta~' of an asbestos controT p;c.ctice st3iidui'd is J.:hc fabric filter 11hich on the basis of semi-quantitative: data appe:2.rs to provide
acceptable control at reasonable cost. \!}rile fab1ic filt1ation \/ould be a key point in a national emission
standard fo1 asbestos, other devices or practices can be required in cas2s ,.,:,ere fubric filters are r.ot practical. \!her2 no effective controls
are av~ilab1e, the standar4 can bc~xtend~d to ban the u~c of asbestos, provided a suitable substitute is available.
A major advantage of a contrb1 practice standard would be realized in enfO!'Ceil:ent. Inspectors could be eJsily truincd to certHy co,;;pliancc
'!lith coiltrol practice n::gulatio~s. Problems of certifying a numerical stand.::rc! are er:orn;ous. The con!i)lcxity cail be illustJ~c:ted by exan;ining
tr:-s~s :;i~houc regurd to ai; pollution i:1 the ge::12ral sense. The rr.ost co:-;,Jcn teci1nique in U. S. testing has bc2n a n~:::mbrane type sarn;Jler \'lith light 1:1~Cl~osco;Jy used to analyze 1 '-f~:)rous pc:r;:ic1es 11 Sv.:nples are not
tJken i so!( j net i ca lly as recort:;:end2d by OM source testing ll"tethodo1ooy.
FMSI 03087
.,.
... '~ .
be
ner:esscn' . ' ""
to
dcvclGo'
an
isokinctic
procu:urc
\'lith
ptOfJ!::l' llOZ!:le dir.1CI~Sicns to pennit il1euningful S:Jnlpling Of asbestos e:~1i.ssion
sources.
The fibrous particles" rc:;or~:cd by ii~c'usi:rial hy~ienists are by no
the nature of th~ soulce of Uw s;::~:ple. S;;ecific identification ol- asbestos
rcquii'es the usc of x-ray difflac::ion techniques coupled \lith visuul
representation by electron _microscopy. Analysis of samples coll~cted by
mernbn;.ne techniques and cou~ted by clectron ::licroscopy is an involved 2.nd.
costly procedure. Each s0mpl~ r0qJires 2~out 20 man hours at a cost of about
$30 per man-hoJr for analysis.
Everi these sophisticated t2.,c!1niques terd to distort the nctual asbestos
content of the S<.lmp1c by i ncreC\ s; ng the nu;o1ber count of fibers during
pn~pcnation. Thus tire analysis is not mcJ.ni~1gful in te!)Orting total r.u1T!bers
of particles present in the original sa~ple.
1.1 f.\sbc:stos iiining -Asbestos m1r:ng \tas detenninc:d by Davis (ref. l) to be-on-Gcif-the~ia-r-s:?s.t sc~accs of as:)~s tos ei;li ss ions in the U. s. ;lining is preC:o:1incntly Si_;r;',-iCC typ'e 'i:lich is cxtr:~1:1ely difficult to
C,O!ltrol or qui:lntitate ~miss~cr~s. Spec'i:'ic areas rec;uiling control al'C
drilling, Lllasti0g, c~nd one handling.
1.1.1 Drillinq- Drill~ng occurs predo1~1inately in hard rock
usbes'sos riTi1Tng- fo; the r.;u71:/ose of pl.:.cing bL:.sting charaes. It has rcc:~ived consiGctG.!J1c attention -~rom persons int:.:rcstcd in controlling occ~pationJl e~posures. Air swept ~rills arc the rr:ost co;;mcn m;ing to a fL<st c!rilli~s rate, it:ss bit: i;car, and 1c:.ck.
of freezing p:roble;:~s c:ccun;:ercd l'titn >;ec sv;ceping mctl:cds. En~issions from air S';iept C:ri11s :~.:l'le been visibly rcduc2d t!wo~:gil the use of fJbric filters (ref. 2). \Jhcn~ ,,;ci: c!rilling is used a mist is
gen'2J'a<:2d ~:i~-ici1 cor1sisi~s of fine ~s:)~si:os pe!l'i:iclcs <:tnd .,.,,}t2r'. Cyclo1~e collector's co.n C::>llect ~ilis i:_y;:>c of c::tission r:or~ l'(cildily thc:n fabrics \:i1ich pbg \::;::::1 ,,.:e:t ~r~s s:~n~.::rs ;:Jre fil ten:::::i .(ref. 3) .
. <; ---
FMSI 03088
... :~..
1.1.2 sl.:s"'~r!..)-~1 - Th~ lr::f~c_:;st iq::~Gr.ta:lcons Ci:11ss-icn so'..!rc~~ oF
as. b::s to_s_ ':_i_1t)\:1--4 i s orr~ 1J l (~. s ;: i 'i 'J. Co:1 ~a. i 1~:.:~l~ t of dust r:~:li s s i (~, ns
f) ....... '''l'i1d\1--::'-~rn -~ ~ ly ':1(0--.slhl(:.~
1 ' , 1
~r, : , '~,
. ~. ....
f.... ".
.J._ ._
)r
........
.~...
......
-. . . .
;
,
(-.~.
1
I
' -~~~~
" .... .:, :'..,.
; .:.
f,'\,"(:H.~~')l.l..~... !' \ 1 --;; ~in~q
ccn .. r;~ ~~J la:~.IL~d "":_...; .. ln.~ ..:.~ .. :.. -_~;,.tSL. ~....:;~1_i .... v..~ l!t~. :.:g !J, -~--~S
E :,, cl.-,.; .., 1 vnd ol ,cc ci'i.lrc;:..st"'o')f~.\.,.4.,
'-''('''''~
_;I'"''""
~~tJ.r"~, 1_-.')
I:.J I
~-10'" ~;o :o li"i
'" 1<1-
oO.f
,I I
fl V
I
J
"
0 ' . .;
, .J .._,
i's. to r1ini:~1izc dust. \!c:ti:ing.of t::o ~Ui'fuco,.pii;l' to blast pr1;vi!.k:s -1 il.literf. ccntlol (ic.f. ,4). i\s bl0.~tin,9 not q. 0~ily occe~r'r;;nce
at <:sbcstJs n;incs ;:u:d :~wst ~1i1~2s s~ock:)il'c on~. 1i1;riting blvs~ing
.to ut:;:osphcti c cond_i ~i-o:1s \hi c!1 i:oul cl not be conductive to disp:::r~;1cn af the -~1~~;olv2d c\;::t ~. :~;~1ld not be. rf:s~:rictive to the
total opci'.:ltion.
1.1.3 r~(L~d T~'2:!:~::;;;i: -- ~::.:;-iy ;~~ir~~--:: rc~:J~; 01 .. 2 ~ur"r.~~ced ':Ji t:,;~ -:~-~~:::s~r.s
t~lill ;;J1fi])~-.~-coil~:~ir:ir:g :'.DL".Ii: ~~' Jsbcstcs oy"ii.':::!i':;ilt. '1'-'ili.::.tl.-:'
tr~:tffic, some v:~iiic1 ~:s cafryi ng -~~p i:o 2.0Cl tons, grinds ar:,.J ~~:J;a.~.:e::.
the tailings relco.si~1g consid2t'alJlc qu~ntities of Jsbcs;;os :J,:cti:lg
dust. 1!Jny trei'ltt;~(;nts-hc;ve b22n. tried, ,lith \'latci being 0110 of U1e
Sl.ll',')c',1..',-..,-~-'1..
hazardous
(''1Cl"' J' )
dJi,:ing
T_ .n "0~1"::J, : ...... (;..;.'!r ''"- '"-S ro~;:..d
conditions; ho.-:~ver,
tt,,._.u,~i..:'''-".'nt
it is the
\,'OU
1 :
r._lt
pl'or.1i1.rcc"
r.1ining co:;1fXlny:s
option not to sudacc; roads i:ii:h asbestos mill tJi1 ings.
1.1.4 Vc_b_~~~~- Ve:1icles hc.t:.li:-:s asbestos ore are a contro.llab1e
source of usbcs~os c::~iss:ons. )[~~!ling ore results i!l emissicns
thtough the jostl i :~g 2.-r1d air uU:ri ti on of e:<;Josed ore. ~:i1cte
hauling is only ovel' co:11pany :Fop:::~ty, dust covers fm the; ole
-~
;
~.'C~~!d b~ Stl;:-f~':ien~ j~1 :~r~:~~C-~!~::; :!~'?.~.~"'(_ts. ~.'t;i:::i>~t] 1:: ~1<.30 Y!?!'Y
I helpful in lo.-:2ring ~~:issions b~tt -.:c.tet is not all-rays av~i\;.01e
in al'id regions. \!:"!~_:rc t!.. U;1s~ortdt:on of aslJestos ere OVC'(' ~~:0l ic
roads is involved, u~e hazarJ p-r:::sen~ed to the general PJ::._:lation
,~.,ra~... rcarvy~lis l~~~borl<.~"\ s(trreiqfr~""~F~.}in:t control :~~casures. Special dust ti9~1t \.'c~-:icles
1.2 Asbestos ~illing- Asbc~tos mills were repJ~ted by Davis (ref. 7) as the most s 1gni l'i c<J.nt source of c:sb~~stos emissions. Hi 11 s hafe r.t..:::~ci'OUS points of asb:~stos e:lissio:<s ~ncluc!ins: ere storilge, me {l;ying, ore _bundling, ore processing, and tailing dumps. \-!et milling offers udv.:~n::ases in ~~~;}ny areas but is not 2pplicuole to all ores. Tiwn~ is one ':ic~t ::1ill
in the U. S.
1 .2.1
Ore
-
Dumping
-
Dum~ing
of
asbestos
ores
which
are
not
w~t
res ul ts-~rle~l-r s s i c-!1 of Gsb2 s tos i:o (t tr~10S p!:erc;. Other j nd us tl'i cs
have adopteci s_peci2l du>,;-;ing enclosures (n:f. 8). Th~ option is
open to utilize \:ai:er spr2.ys Ot' 8nClosur2s fol~ du~:1;Jing.
1.2.2 OY'e Dli.::J?.~- Ov"n ore dl::~11}S can be c:1lission so:.wccs ~spscial~y
during extlcr::21y dty, ,-:indy l:c;;;.thet. O'.:hct industr-ies e.r:,ploy
n"' n 1"''' sys c ,,,,,.... 1 d s l'"'."tC"I 'II'2~, '- .i... "J 1))'' ", j],'"' 1..:."1 P1
r :- n.!_ .,_.,....,.._J _,...,
0..._.I, VI
I'~ ~'~tJ ;...-. o......m.11 t' r;:).;J 0 '>l ~ ( ',. 0..1')
option is avui'l<:lb1e ~J ~iovid~d -~nc~oscJ storGge.
Tn'I:.:.>_
1. 2. 3 ~QD.'!_~>:.:?.t?_- rot.:.lly 2:~elosccl conveyors ci1~ readi~y prc1c;:~ . -:;hese sysi:e:;~~s /i"c::: b;;cc::1i11J r:;:Jiss-icn sou;"'ces c!u~ing ~cr1oCs of :~~~n 1-:inds ( i'Cf. ., G)
FMSI 03089
1.2.,.~- 9_r"~f~:_9]~'..~~ts - ~;~:r:~~r-a s ty:.~~s of Gsbcsi~os ore dry2rs 2.tc fot'ild. Sc~;:~ t:-'pcs r(~sL:lt n ::>)r8 Gust ~i~!i~.sicns tt1:i~ o~:~.~~--s
rr' .. ~~ .. ~ 'n t~~"' t:c;-\"~C -:f 2.ci ;.;(};~ ::.~"d ;-1~-- V~~c,r-ity cnr:r)!.:~~~:~.,.. r.(~
'i;J vr.e Vc'C! _:\!1 i rl\_.: c.::',J ) :~. ._;:;!,(tS: ;..lf!'J i i .; ~~ il:~:; :.. ri ed s ..:-;\'.:;{"~.~ d~'.'ices i!1 the CJi:<:~:!f;:'n cp:::;Q:>ions C\nd ha.ve found insul<:tcd bttsllouscs to be the r~'ost 2Hicicnt etnd not econor1ical1y
pro:1ibiti'IC (ref. ll).
1.2.5 Otc Cn1shcrs Ore crush2l'S ure a continuous sourer.? of
dust e~li s-s:;-;-::J:1S-:-ri1 scr~~ opel',:; ci c:1 s ~ri n~tt ty crushing 1:~::\Y b:::
s!2pGrate f)~or;1 ~he r.!din opE:r.Jticn c:~:d t:ncontto1lcd. The c:.~2rr:.Cicn can be co:1i~rol1cd by cr.closui'C L'.;:J hcocling (ref. 12).
1.2.6 i,iiLl_f_._:ir-- I~1 hol:i1 \'Jet and dry milling air is used to cc::-;::rol cl!Jst levels. Liry clilling uses cir' cs the sepdruting n~::cliu:n for asbestos fibers from its lost rock. Fabric filter installations are found on all well controlled mills, some handling as much as 4.5 million cf1~1 (ref. 13).
1 . 2. 7 f.tod_ll_C t _r~~!~::_s_i_r..:.:J. - i1any of the containers us ecJ to s :1 i p
asbestos fib:?i' are not Just tig:1t Ol' sufficiently du1'2ole ::o
'nn~vent S'Jill,1ge dutin~: shipping CZ!nnoi: re.::dily
sbhei:"~:o~n1;2;n;t-.c-llAeds
emissions occun-ins dur~n.q by capture, a n;Ol'C posiUve
i.l:JDroc:ch to c:nission cont:ol is to Oi'C'/or.t le2:<s fro:n occJ1'ring.
So;;:e ns bcs ::os cor;1~ ::n i c:; il !'!C: us "ing c;d: re1~:e 1y s trcng bi:\9 s ;; t li t\:1 e
cost pcn01 cy. D1op :;cs :s are co.~~;r;o:1iy Liscd i:o l:!cC\sure t;o
durilbi 1 i ty of l OttG'~C:::;cc:<.1ges.
Gulk s!1ir.:::~cnts ;_:;e:s~ni: di:'fc:;:nt proJlci~ls. Sc~ce 1o.::cling .Jnd unload~na SysteJ~~s c;;~ploy air con'.:cyir.g of th2 mat.c1~ial. ;\1-::e:r separation of the luY,gc fi::.ers, the ~:<hJ.usting air must b~~ r~rJ!1tro nr!1I,_.,...
by fabric nHration ~o c:lin:in:::tc -::h<:: il1'/isi:)l8 sub-miCl'0!1 pa,:~ic cs. Dust tight '/ehicles are a ~us~ to prevent emissions during t~cnsi
Labelling v.s ~o as1Ycstos col~ cent is an im:)ortant aspect of er1ission con:~rol. In the event o:'" accic:cnt, cle&n .. up oc,,s ciln be advised to use cus::lcss i'12thcis to rf:!n~ove S;Jilled matcrie~l. Shipp2rs and h.:c!~cllc:'s ilill bo:: u'::Ji'C of the need to avoid rough handling and to mi~i~ize spills.
l. 2. 8 Tu il i nn~~!!c~22. .. Tail i r.J s dt.!~Tl~s a l'2 1:~a s t often ex ~::::ns i ve
arcus of c~posed sp2nt ore. As~cstos content still exceed~ that of
nonnal SUl'f(:CC n:<.1tc.:Ti0.ls. Emissions occur durinu conveyin-::, b~;11-
o~ r!1~-;--, ,.!,i'r",CD~ ~-.n~~ "10rc~Sclozing -
r:!-l,,:-:.1... ..I '-' \.., .......,
.,..
~ J-
...,.! J-' .\
hv )",.('lly'("l..._-'
1.~' I'~ ,.... .,/
I ,l,~
-
\
..._
~-To rl~:l'r'"l'/
l'
......, ~->..I
_
superior r:12thcd has b:.::"n 'd2vcl o:;2cl fot ull tailing dL:':~ps. [;;c!l
ope1utor n::_:s~ decide: \/1ich r,::~~~hcd \lill be best ut his loc2Von.
\!etting, chG!;licol t;c.}i:::cnt, 0nd n~fotcstai:icl: hr::vc b(;cn usccl.
G.:.:-
FMSJ 03090
~~t~st0}~~~W~ s~-0-~I~i~-11~-,~ ~-D~~s :~;. ~:~ ~ !,~ ~- ~;~:~~~;~~ \~;;~~~~~;:~,~~ ~:.:~ 1.:,~ ::c(~.
;so~}/~.,~ 38G~) ~:ses fO'f' ~1sb2s~~s :::~~'~~~ ~.;.:;n c:ocu~~~\_~JI"Ccd. i\i1 cstir~J::cd
, , 11, ,_, 0!:'. ,._,lj2S;C~(i' l. !i :- .; .
-.:(
.. r
:;;.i
. ~--
.,-~-.
:.)
-., -ll , -
. . l- . . __. ',
1\,... . 1. .:, .... , '
1\;:,
-
so~1rc~s Jie '/iU'icd ~nd c:Lr.;n C~ff:J~e, th2 :esulutfonS J.re lirl1;~~~:.; t:c
e1:lissio:1 scurc~s coi::n1on :o l!;ost proct:ss2s.
1.3.1 ii;;nufC\~tutinq- So~nces of emissions il':~lude gvs s:Jca!;ls
used to-COr1fl.C-l dLiS--t: l~vc!s inside iJlants or as p~rt of -~J:r..~ process
itsc~lf, such 0s o.il' conve:,'ins of ~::<:1:2tiu.l. Fabric filtr~1s il-:t'te
been lr~ilizc:d cxtc:nsi\r2ly \.=i:2i"2 rccirculu.tion of <J'ir stt~.::;!;s ~s
1:1),-lr..,~~l'"'Cl
.... t,# .... I '-
(\ .t .. ,-.r,.
1._ 0...'..' n'-Jr~_". '..:...r, -1.,.-,._;,-.'".I;()~'"1'""-"~1
.n'.~"'.r)rl!'r'"S
...... ,.:' ...)
.._.
}"d'1.;.".'1\'/'-........,
't )
,
'-"\~ni)
:II;,-~,,' .,;~.\'".',.l~,,'o~:'.\d
by fc.tJl'ic fiitrJi:iGit ;::::d t:Lir' :2::ircul2'c.ion (n~'f. 15).
Son:e r:ia.nu'fc.ct:..:rinQ op:~rc.ticns g2ncrt~te ~xplosivc Ol' fire: huz.:trd dusts. Others such 2s usbes i:os P<'-PCt' ~;:~nufacturi ng vcntil otc ext;e;nely ,.;et gas strcc::ms. Such operations are best cc:~tlo11 eel by high efficiency scrubbers.
1.3.2 Ventil~tion Air- In genrral ~ost plants maintain
occu po.ff()naTfi-s<:t {c-Tevc1s \'IHh-; n ti1e \Jotk i ng 0.reas t:nd \:here
such levels dre :;1 -::ti!lt.;.in:~d e;d~aust of in-plc.ni: ait to the
at:nospi:ere l:o:.tlci n0t C()~lstitut('__ a_signi-1-icunt 21nissio:1 SGutce.
f
I.10\'.'C'/Ct,
scn~e
o~2:,ct.J cors
pre,_cer /"
~
(0
'::qu1o p
pcrsonnet,
o 1I
\Ficn
res:J.: ti.1Icors
rJ.thcr thJ.n control dust 1cv2ls c:nd v::;nti1ation .:\ir ftO'i1 tioesc
operutic!IS cc:.n be! s~c;r;~fic,!nt 2~~1ission. sou't"ces. Suci1 sc~Jtccs are
reudily evident by ~:;c sCC'Iii;'J1ction of fibrcus particlc:5 Mo~md
ex!1aust points. It ...auld lJ.:r;:.;rit op2r"2.tors to 1;:aintuin sc_(!=~ irn;Jl~.nt
l e'Je 1s ra th2r than be f~:c~d \'Ji t:1 ~h2 pfospect of fi 1teri ;19 l0.t9C
amounts rif v~nti1ation air.
1.3.3 Pl'Oclllct Si<ir>':~~~nt- The larsc van21:y of <lsbestos products requiredfl'Ti'r~n-tiLo0Y:ees of p.:1r:::<c:sing to linrit emissic:~s dt:ring shiping. So:ne prod:_;cts r:~ay not r~~quir~e uny ~;J8Cial pac~~ing, SiJSh as filled plastics Or' vinyl tiles. Ol:h2rs, such as .;.s~):~si:Gs cc:;l:::nt, require dL:st tis:1t p.::.c~~a.s2s ec;t..:iv,:;l(;r;t to fib2r shippir.J bc.gs. ;.~ore k:~or'tant i.s tho requirc.~,cnt o~ 1::<bc:il!ng to instntc~ us.:Ts i:o h0.ncllc 1rith care i:l:id to ut:il ize ~lo:)Cl' disposal !:;eti1ods.
1.4 Prodt.:ct Usc Prcdusts cr::::~t.:1inins asbestos are used extensively in
the co:1 ~.i{i.-. ~JC t f7J11 i :1d ~: st ~--y. i-~~~iJ us ers n2'.'t:I" s!~nt~ :--;_~ te d~ s t fro::1 the
!Ji'Oc!'.I- C'L.-.
ri11's ,,. ,ty ',:"''~r~"''.J ....... ..):_ ............ .-1C..,\,1
~ .... ~ C...t"
;,""....:,..:.,....,. .t..iJ.,..,t.~....L.'s
\=}j_:o.l...c,:
l~..--1..1
,~
....
;>ch,or~os
..... _,....,._...) ..
firmly bo~;;d in a n:.Jtri:: oi' pl_y:.>,~r:c 01' cc;::~r.t2t~cus ~~2teri2l.
orusers scn2rate sig~1ifice.nt quc.ntities usbcstos c~r;issions frc.;~1
ls
o~~hGY' asbcs~:os
con{~ci!1'in9 poc!uc::s .-:h::re i;h~ asb-::s::os ~s not fir~:ly b0und. Rc::;:.1la':ion
and cnfc1cernent \iill bo diffic:Jlt a!1d s~:ccessful con.trol 11ill ck::2r.d
upon p~t0l i c J.\'.'J r:~ 112 s s .:; '~'~ cone :;rn. [1~1 iss i O'l contro is have be~r~ (: ctc 1opr;d
for bo useful types of products.
---....; FMS\ 03091
l.fc.l Cleek 'I:-ISL!L1.-;:ir_n1 - Ct.~Cic:::l Sl11c0-:~c l-)1o ~~ ins1Jlet ion is Ll s f:t~ exT:~-.1sT;;~-iyT!1-::,: ::;-,;_~(\ 1 i:; :- !) ~ .} t ion (!; q1 i cr} jon s . T is
. ,, ~n~ A.S lC'"'':_:;b:.. ~.-- :., tl SOr~~ !J:_-.t- .., .--~_, .. ,-i:t ;'
,)y-llt:O .,l", c~t...l01 'Jl1.:.:-r.-~,o.~rS ''~"1<"1..-~, l",c.1..S:~._~-,:.,. '.\."<'.: ~r-:l.':'fO..r. ";.",..-., ',L1,.-G..,I,..d:-,'-.,,_c !.,J,... -,,~r _,..,,..... t...O
intrct~UC2 ;Jt~:.:;~~a:c:~o #bl'JC~( for 2cnds and joi1ri:s \.:hich the unions c1uili1 \'till be d2Ui~:>:cntal to U~:~ir txade. P!'C!;;o1d2d insul-:<tion \toul d gr"'2J. i:ly rcc:.;ct~ c:1i ss ions fr--o:n field shupi ng o-:- these ptC!.~!cts.
\!here cutting is c:ssci:~;.:cl sp::;cial ScH/s have bcon cL~velopcd 1'1:1ich have fabric filtr~c.tion of c>~hc::.us::ed dust (ref. 15).
1 ~ t1. 2 P\sb~:::-~ ~~ss ':s:1~:.:~. ~ :! '~:~ ?-.-.::>:::..s P-::.. !~;ro!lS r:s:~::c:, ~o\:; ;:tc:~-c.ts
1:1 ;t:12 1Jr:.:~_~-il-- us-.~-~--~
~-i~~.:- ~~-~-- ~~-~~-:~r--1:,_:-.~ ~!~- ~~~.:_,~; (:y. Sr.~:::~ .~t;,.:;; . _
. . .
cc.~~erri: cc~: (::in 15 ~G SC :-=2"f'C'2:~ ;~ ~-~s:.>.:;s L.o:; .. Th~.;~/ ~:.:c ust.1-:: 1ly :::; :~c-~.J
in open troughs 01.. buc~~r~;:s, c.::l2asing lc.rge quantities of <J.sb:::tJ'tos.
Soc:cial pc.c~0c:cs ha'/e :)-:on cl::~v2iopcd \:hich oer:~1i t intlocll:ctir;n of w~tcr and mixlng prior to opening (re~. 16)~
1.5 llas_tc _Dj_~_t2_9SA.l.__0J}~l D(!:~91 i~ti0'1_- Disposul of asbestos cont0inii'1'J ,_.:.-:-.s:~es is a VCl'Y dispersed c:::ission ptobic:11. \!<!stes containing usbcs:~os inch;(~r:
shipping ccnt<J.incrs, i;:::;~~vfac;~urii~g tcjcces, used pi'oducts, ard collr::c~0~::l
dusts. There is little or r:o tre.:r;::~~nt given to 1:c.ste n~ate-:ials COi1tC\in~ng
usbestos 1:~th rcs:;ect to ;nini:r:izLs:---e;:::-issions during disposal. i-:_:sh
matetial is disca;-cL~d on op2n c:u~,;:Js 2nd becon;cs a continuJl sourr::r~ of
-- er:1i ss ions.
.I
t-li.,g-.1.5.1 Re:tiOVi:'il or ,':if:)C'>S::os CC'1 C-:'ininc; I!1SIIlation - t\s tll::~ost r_-;ery
bui 1d; cor:Ei11~-;--So:~:2-as-sc~-s-cos-:- tr::c-~;~!1 a on ; s 1im i ted to
structures ccntc.i;r~ng over 50 lbs . The )"CjUlat~on ulso (~P;J.ii~:d to
indc:st1iul- and s:1ip c~!ilc!ing cp2i'Cltions .-1:1cre lurg2 i.1i;1Junts of
i nsul at ion a:e b:; i ng us cd. [) :i -~ish ens i ::c~crs ha v2 pi oncc~e:c [ n t:hc
use of water and special injection nozzles to wet insulation prior
(r""l :7)-'-L.O
rCI~"' 1 c"l \,"..J I l;,l
"-
;-,:o-:::':"C10'~'!''C
'-II
\o. I
,~_.. u"tSO h""l1~-........_, I..4'S'''-O ' t-"o l.;',o,..l;.~l. ,-\ -'-c\.,..,1 ':.,)) "I 'to):l-'pI ;-j :.r,
conta:rinG.ticn. This st<!:~dard h.:ls been 1eft l'elativ2ly unn~s::,ici:ivc
to permit freed em in devc 1op:;1::::1l: of nc,-r and i li1[Yr'O'.'~c! rCI::ov_.:: l n~:::<:~ods.
l . 5. 2 ~!0 s 't_e Di_S_E'_:?_~_l - The '!~:~t:~cd o1- ul t'l ::1J i;e dis post\ l '/!hi c :1
r.1ini:~iizcs GS:;c:stos e:i:issioil to ;~iH~ tti.:mosph2r~-2 is sL;;)su;~"facc dis:)osal. A \/~11 opet.. ut~c! disposui prosrz:i;: \:ill h~'/t: to be c:.;!:cb~ishcd ir~ ,;;.1ich asb~stos \','estes are s~~grcgJ.t(;d c:t1d :) 1Jt'icd. These progi2.mS Cr}~) ';)C ccop~ra c i vcs be t.-:22n !:~,;.. nu f z:c :~u i:: :"s , cons t_ruct :en con t:.. (=:c~ors , de:nolition contr2c:~ors 0.nd dis~::Jsa.l JT'22. f:\1nage-rs. This ;.>roa:"'?.m must include ;Jrovisions "Lo i7lii";iir~i-ze~;;Jissions dui. i!l'J Jll p!~~1ses, including transpo~tation_to disposal sites (ref. 13).
1.6 ~pc~jfi_~_Pro\1_~_-L_tj__g_o._- In cstc;b1is:,;ng ri-;ctous c::1ission stui!Ci<::r0s,
coi
.i
consicJerution r-iusc be ui';cn
tl12 ~"'2CO!~:;:~r.:Ildtd.:ion of p;-'oi;i!Ji-'.:io~1 of
thos~ uses nf h~zsr-do!:S ;;i~t2r-ittls ~.i~l~;rc; G(!cc;ui!-::2 ccn:trols hc;_vc r;Qt !Jec1
dcr:ionst.r'atedor v1h2re che hJ~:CJ.!..d prcscntc:cl 8;-~c(eds -snc v<tluc c:.c:1ie'tcC .
.~
~-.
\
.J.; -::;:-
FMSI 03092
;:;~!h,~':'i~~~~t'~1-~;~-,~tt::;::1~~::;";~~~1f~~.;~~~~~~q;;:'i~~s:~:;r';~:. ,.,;Y
.. J
_,"'(;.___ ,.. .!i .. ic~~ -- ..~ffic ...~.;~ ;ii
-,~:o
f--~C: 1/I Yor::, :Jililr.~:2l:.::l~l, 0n-~ S.:'.;; ~rt:~ncisco ,Jr~ CCJisirJctir~~; rc:~L:l~-~-:~~o:is
. to nlohii)i ~ the us,,~ of asi)cstos conti'ti;ling sph1y fireprool'-:nJ. Sc::~2
hGvc\ alr2.:t'lIY 1' nst~' l~u-1~0.d pr' o:lI lo 1~1o ,: ~on -1chro;,.;,~;!l :Jer:nlo"L0 ccntro11. ~0 -f ;any_
unplovon control S)'s:~r;::;~ls for :>prC\y-ri19 have b:::~n pro:)osed. Sen~ h-c.v2
b2en proven inadcquilte (ref. 19).
Spray fircp~--oo!~;~~c! 1:12nufr~ctt:rer'S fl(!'.'~ responded rcq):(;iy tc "'~:1~ cit 4es o~1j ~ct i en; b)' i l! treduc i r::J non- i.;_:;l;cs tos co:1 tc1 in i 11.'J :..:_;;) ~-; Li ;~:_; :::-:~-s
l:':.'hi c:1 2 i'\; cc:~ :i ~-;;~1: c-~ y cc:n;:~::-~ i ;:,~\!C. S1. ~ ~: st~ i t:.rL.r: :1~.-~. tr~r i ~~ ~ s C:: -: !~ ~
used S~~ci: OS t-;;<pGr!:~~\::d './Cr;.:i c:Ji i ;~2 1 fi bc~r 9l ilSS c~nd 0 ~f~~~f"' ::1~ r~r.:~r-~ 1~-: can be :.1!):-:!:icd L:-sirrc: tl~c s:7.li:2 C:i~~.li~r~:~~nt ?.S used -for asb-:~.s::-.J~; c~:!~:>.1~~~in~ co1~1positions. i'lo udditionu1 op::,tt~tOi' truining is required.
Cities are also concetned \:rth a-sb('?stos e::Jissions ',;hich vtil1
be g~nGr~r:~~:d ~.:h.cn csbcstos fir2ptoofcd b'Ji 1dings ere dcr~cl ~ sh,~d.
Asbestos fin~iJl'Oof'i::g of structutal steel ..:as not inttodJccd u;r;;ii
the -l~te l9(10's ~nd fe:\t builGins trec,t2d in this munncr hQ;c i:~_;cn
demolished. Offlcic.ls estimate the yeal' 2000 \ri'll be the ~cyitllli~g of
cle;ro1itio;1 prcblc:~.ls.
,___
r
The presence ofsuitablc substitutes at little or no increC\sc : -~~. in cost a;~d diffict:l i~y o~: r::mi ssions co~rtY'ol durinq both up)! ic0t~':'il ..~:_ .:>.nd cle;~~c:1 i ~io:l i~;.:lir:::c:.:: !;;;;;.t pr8:libition is \'i2ll"r<:.ntcd.
1. 6. 2 :~~; scc11 (;i~r.:c:~~s Us2s - The 'finely clivi Gcd nuture of (tSl)~~s tos floats -~\ncrs~~rfsc--_=~::-i'i'i1Cd \tith 1;f-1e cbSO!'Oitivity and chc;l!CJl
i-nactivi~y i:1-:lkc U1c~~ ~orms lik::~y cc:nd~dc.~:es 'i'o~- i.1bsor0i;;s s;stc:n and, clispc:rsing n;~di~TlS. ~Oi:her i:ler~ m.:l~c~ials ul'e <tvail,<::~lc ~o; sucn p~irp)scs, tnc us2 or asbes:os 1s hig:lly um:an-~nteo ~t1.nc.-1-
of its hazuc!ous lVti)Jt2. This prohibits such uses as inscct1ci(i2 dispersants and oil i.1~sorbants (ref. 20);
2.1 I..S_t:i:~n:c~r.~:_S_:;_sciX_ic.Jj;_i~"1_S - Si~2ci i'icaUons on required control cqui;;:;1cnt t:re i;ri.:r~ndcd to iils:.~re C[jui/ulcnt asbestos rc:,~ovcl cf(ici~ncy. l~ost of the spccific2-~ions ar~cbascci upon b2st c~:rr2~t instc1lluticns.
-2. 1 . 1 FJ._b ric _Ei.L~o;_~ f <:!J r ~ c f i lte.rs il i'2 -~h~ pri ;;-:a ry ccn ~xo 1
device n~c;uir<::cl b~' !~!;is n~suL<tion. Th2y n.1v~: b~~;;;~ repcd2d ~o
be bcti:t.:i' tiBn 99.99 :;c:rcGnt efFicient 0'1 a n1JSS basis col:cc::in
?1) 'c"'S-L'sashr.~i:jos
. V\........., _,
IIT;I 11l
ciL'".Jt.-
f\ r--\n~,-=
-
r',(h~ l~'~'l r.,'-,:.~--J.1-~i...s 0110 ~-
(_", tl, ,I,.,_...".J;~.I,,l't'I -1.1 "'
fro:n fa0lic filters she~; that ~i1e devices cdn control d'JSt b2lo\'!
occuputi~!:al t!T2Sho1d VJ.lues.
FMSI 03093
B~s!~Guscs h.::ve :~~:;n.J' yc.::li'S of clc~onsi.::.:.i;~d ~~~f~;n:Gncc in:lt;ding
O'/et 30 yc~ts o-; ~i~2 ~:i (he ;1s:\:2stos i;~c:L:st:ry. The G~-~'.tices Ji"'G
}'"'f..~1i;~:"'ll(~ C.ll!d (:;:"',~.P.,""'''~ ......... ;_., -~!-:_,.',.,,.. .~-.. ~-~~"" 1 '~-~i'-. ;~ ~~):L -C: j;~;
ov~ : :.:. ~) r;~ .;: nuf ,~ c ,__;' :; :s s'_: 11 ! no ~: :.: ce .I' SCCJ unH s per y: :J r . 0; c:: I' l i :) , 0:J :J
s -- v:.,y 2'))L.,,, t
.l....
u;'t!''."_ ~1ll 1~t's..~_ cc_,._l"'.~
r\I'"\'_r.I. -'
oT2.1.1.1 Const"r"t:ccio'l- Consi.:ruc~~icn is specified to pre't2ni;
eroi ss i ens c::11~-22Tc:J clus t.
2.1. 1. 2 .?.)2i~-~'?_s_ -- Ti12 :xo:1i )it ion of by:).::sses i ns,_!:es u~at plunts \Jil1 ::o;: 'J;:<::u::e inc::; unr:oi1ti'Ollcci 11EHmer.
2.1:1:3 t.2.:'!.::2.Q.'C.~ _i:!?ny l'iHcr '.iSC~l:s 11~'/C no pto:isions fer
empcyr.g hop;;~:rs ~:/1-;::lC.~Jt rC-{'2letlSing che dust to the Gtr:~os~)i1~re.
Fabric fil i.:?i' r;z:nc.;f.::~::tun?s iluvc~ dev~1oDecl m.::ny S_J'ste::1s to h(~:1die
collected dust.
2.1.1.4 F2btic_~- F.::bl"'ic efFiciency is highly dc:pencc;;t upon
ah flo.-1 pei~;:.:;:::n i~y. Lo\'/ 2ir ocr:;:ec.bn ity implies trat ::::0
fabiic 11iil hJve hig;1 col1c::cion efficiency. The ratins 20 cl::~/rt2
at 1/2 in. H?O is c:~.:iv.:t1cnt to stuwJ.:rd cotton bags .::1:c:1 :1-;,ve
uttt~ined 99.~9 ;::c)cont efficiency. Tile ruting of 30 cf;;~f;'::?. <:\t
l/2
SLJC
in. H20
CCSSfufiy
i
s 2:1 ::::quba1e:r~--('.::'cing
oy in-:i:Js:~ty. f<:lb~ics
fot o hdVing
rion fab higher
rics
pCrT
used
1:eaoi
li
t
i'
2
S
\li 11 not be p<-.:!'!'Ji ::.~~cd.
2.1.2 /\ltr:l'l1Llti'i:: Gc:/~cos - T!1210 <1re certain conditions L'hc:rc
fa btic -:-r-il-Ee -~~-z:~-~---.~--!10 -;: ~~~P-1 i cGbl c . The s:: inc l ud e vc:.. ~, h_:;:; i (! 2r:;:J ~ e~~ ;;
temperature~ gr~S s;~;-.::c:;~:s ,::1d c;<plasive Oi,., f1a:l~r}~)lc dust 1occ:s.
Scr~ib~)ets are bettor S'J i teet fa:" ~hcsc cases bu~; Inust be sn~c i Fi ed
~T....O
;;a) uG"
\'ail
I
't'..<~'I.f._)
I"..0:-1'.' -, \,1 t-:"i ,C-1J".I:.:,
"-" i\,..;:; I
'f=
.
r....,
j
C
...
.I
].r..
.\.}f
inst~l1cd c.t rn-::\n:Jfc:c.tuler be Porthe cptio11 c-J- th2
on o:r' !~-,. ~"r]iJ.. tl
ti.'
lAl 1'
I'] .I
.)
.. I~r-;(' f.. h ... J ...r..r......".)
must CCl'tified
compliance.
2. 1. 2.1 .?sr:.:f:J.?~22.. - High ene:gy venturi scrJbbcrs are ti;e :::est
efficient t_).:pc:of scrubbc:l"' for sub;!:-icc..on particles. The :)-~"CSsLn"c
9\d'5lr~io~th[Josfscffr112cucbiebcs~s?;Gi~"rc'"y".Jd'f::'fJ:osrir-c.;2,.gScuorJFopioc'":ntfyftiicci1nicc~:h~snecsiy:l
tt~'e f~i9h end vai,.,Y so::~c::.':~~t: o1f12oilredscssu!rs,e~c:dcr!"'o~~;;,.-~;ti1s1 (ci:Y:~rt.2.in23).
2.1.2.2 .Q!~)-~~:: D~v~c~~ ~4,P~lte{nl~tivc c.!2\:~ces insi.:2111ed ,.,;~2rc fabl'ic fi.Jt(~rs 2f"2 c:~IJ1iccblc !~}:.;st b2 C~l'tifiec! to be dt 1east
equivalent to '!"r::;dc fiHr.:ts. -This n::gu:cuon is not intc:;cled
~nlir' '''1:- r(l~;-)'01to ~;:JpiO'/CdDi't?'.'C:lt 1dC'!210f]T:?:!i; Oi: Pr o",,.,:,l.r1r>.....,y U ..... '--11., . (11\..~'..,. ._-.J.\,....
c!c;-iccs
I '"--C Jl.S...J"I-O1'1'S
:)tl'C
is
ccsicncd
_,
:;:)
It is not possible. at '~;~is ti::.c to c1c2riy define equivalr~:~cy bcca:.:sc
stc"~'d1'r1(1 1t~C ' ~_.,,, rh:.~ "',-,1~of th<>'-' 1 n... I 'g
oc . 1:i'c,s tl'."'.,.,...,.,,,l,t-:" "'-'""lc "' 'l'~ 1 ~ ~ ~..; ~ ~l
:..;
.'"\. . j- , -.... ' , , _. ....1 .._, ,. I J
IC I
1 . l.. 1
I , , .~
FMSI 03094
' I ' . : '- r- -''""'"' ...........'
cc;u i vo.lcncy <J,~ta ..,.,; ll ho.v2 to i ;~corpoi'2 tc d0 ta from botf) fcbri c fi 1ters a'id til~ inLc::-1ded aHcn1o.tive dr~'/ice l1nc!cr si:>lilar oporuting conditions.
;:--
-_-__._.... FMSI 03095
1 .. D.:tvis , ~-!. E. N.:ltiOI!t'~l 1nv~..-;-:~.:,_)"'.' of So~~l~ces and F~:t.~sslons ... Cad:l~i~i:l,
i';ic:;el, and !\sbcs:~os. CO:ltrol ::o. Cl?A 22-69-131 }:APCA, c::>:'.l,
Feb. 1970.
2. Grossi::'JL~ck, G. "D~tst Control in Open Pit En3:, lO:July 1963, P? 21-25.
nnd Quo.r:ryin,g". 1\i r
3. Ibid
S. Earr.~on, J. P. 11 Usc of Lj_,snin St~l[ot->:1Le for Dust Control ot1 I!.~'..!l.-..l_s~
Ronus in /\rid ~egions". Dcpo.rt:ccnt of Interior, Bu. l<incs, I. C. SL~07, \:.:lshington, D. C., i;<trc~l ~969.
6. ~annick, L. J. "Control :Jf P.::.rti.cula~e f.m.lssi.or. fro:.t Lime Plants - A Survey'' JAPCA VoL 21 Xo. L;, ,\pdl 1971, p. 199.
7. Ref. 1 Toe Cit
;--
..
'I
3 . Ref. 6 p. 200
9. Ref. 6 p. 199
10. Ref. 6 [). 199
ll. Hutcheson, J. R. 1-1. "Environr.:cnt>.J. Control in the Asbr.~stos ;:,~ci~:str:y o
Quebec". 73ni Anmcal Gcnc~2l :-:ccting of the Cc:nndian Institute of Nining and (:ctnlluq~y, .Q.:ebcc City, 1971 p. 9.
12. Ibid p. 5
13. Goldfield, .Joseph "Fa0r:.c !'ilters in ;\sbestos ~linin;; <'.nd 1\sb2s!~os ~!(1nufe1cl:u!:ing" APCO F.:t~)ri~ Fj_l:.:cr Symposium, Ch::\1:-leston, S. C.
:-htch 16-18) 1971. p. 3.
14. Ibid p. L1
15.- A"sbcstosis RCSQ1~cb. CO!..!ncil, 11 The CO!~tl:OJ. of Dust by E:(~:~aust v ..:n~.:il.J.t~.cn
\.[hen Horklr.g \lith Asbcst:_os! 1 Control .fl.r.d S:..1fety Guide r:o. 7,
London, 1970.
16. "Asbestos: Frier.c! or Foe" ;::nvi:-onm::1tal Science ami Technology !>:727-723, Se;Jtcmbcr. 1970.
FMS\ 03096
!8. J\!3bf-:-;tusis. !\cscnrc~.l Co~!ncil, 11 Rccc::wH~n'tl Code of Practlc~ fo~ the E.:~J;clli~nr, t..l.nC Dis?G::;::.l of ,\.sO~.!stos \.'.?..s~e ~k:.tCc!..c::ls 11 Lon~o:1. Sep::c:,:bcr 1969.
19. Gcorsicff, N. T. Trip Rt.!po-:t to D. i'-1. Slc-.ughu~r, NESD SccUon, 3Co,
o,\r, ~!c.y 13, 1971.
'.:~~','._,i"i;:""t, r '.:
'.~.:~.'."}!.:._-:
\-:~_\;_:.C'l" ~)i.l :_'l~, l 1_tt.i.:):1
?.1. Ref. 13, p. 18
22. Billings; C. E. 2nd \nlclcc-, J. ":1c.r~d0oo:~ of Fahdc Fitter Technoio_sy" GCA Co1:pomtion .. Dl:'C:': r:A2CA C<;il'~nlcl ~-:o. CPt\ 22-69-33, Dcce:!b~c 1970. Vol. I p. 1-~0 - l-37.
...- :::..--
FMSl 03097
--------------------------------------#'''