Document zy3oBL1ZpVMZ8QwEYQ3LqR96
FILE NAME Brakes BRK DATE 1985 Apr 25
DOC BRK239
DOCUMENT DESCRIPTION Contractor Review of Comments on EPA Proposed
Rule
WORK ASSIGNMENT NO 15 Received March 6 1985
ANALYSIS OF COMMENTS RECEIVED ON ISSUES A THE PETITION TO PROHIBIT THE USE OF ASBESTO
EPA Contract No. 68-02-3861
COMMENT CATALOGUE
Date April 25 1985
Submitted to USEPA
Office of Toxic Substances 401 M Street SW
Washington DC 20460
Submitted by Dynamac Corporation
Enviro Control Division 11140 Rockville Fike
Rockville MD 20852
CONTENTS
INTRODUCTION eeveoreeveeveee0en ec Peeoevovevree veneer eevee eeee ee ee e@eetetee@ ses eee
Page
i
I.
IDENTIFICATION AND RECOMMENDATIONS OF COMMENTERS ..... eeeee
I
A. Trade Associations ... evpeveevvnevrevreeeeereveerees
B. Vehicle Manufacturers ..
C. Brake Manufacturers ..
D.
Substitutes Manufacturers ..ccesceevecesves ccc ceeecence
E.
Miscellaneous Commenters ...csscccceccecreccercseves eee
10 14 17
II
LEGAL AND POLICY ISSUES ..cccccsccceceeonesevurereerssevescs
A.
B.
EPA vs. OSHA as Regulatory Agency ..-serereereeeeverees Demonstration of Unreasonable Risk ...-.-seeesseeeees
II
II II
III IV
HAZARDS ASSOCIATED WITH ASBESTOS USE IN BRAKES .........---
III
A. Epidemiological Evidence and Case Reports ...-.-.-+-++B. Health Effects of Chrysotile Fiber
vs. Other Fiber Types
III III
C. Asbestos Release from Brakes - Properties
Amounts Exposure and Health Concerns .....-++-++++--
III
SUBSTITUTES
wc ccc ccc sce c cn sne cece ees errs ereerererereresers
IV
A.
Emcor 66 .isccccccvercencereccerevevressceseresersscers
1. Applications and Performance .. 2 Commercial Availability
3
Cost
ccnccsveveresccece ceeees seer een eee ee eeeee senee
4 5
Health Effects
cc cece ence err c cece
rcetrvcceersess
Experience ..... sec eees ewer eev re eneee eeeeeeeere
IV IV IV IV IV IV
B.
Phosphate Fiber .....-sseeeveres eect c eee meee e rere eeeees
1. Applications and Performance ...
2 Commercial Availability
3 . Cost
4 Health Effects
........ sec c cece renee eae
pene cece
eer
eeeeeees
IV IV IV IV IV
C. Carboflex Carboflex Carboflex Carboflex Carboflex Carboflex ...
1.
Applications and Performance .....eeeseseeereereees
2. Commercial Availability
.
3.
Cost
Lecce ccasrcvvesevenssseseeves emcee ere
reereree
D.
Kevlar Aramid 2... cece ecw c cere nner ne snerrarercreeessenes
1.
Applications and Performance .....+-erseeereereress
2 Commercial Availability
3. 3. Cost Cost .
4
Experience
oo.
ccc cere cers enn ec cre reece nsercreereeee
IV IV IV IV
IV IV IV IV IV
CONTENTS continued
E. Substitutes in General - Availability Performance Health Effects Safety ...
IV
F. Special Considerations for Existing Vehicles ........-.
IV
V.
CRITICISMS OF NRDC PETITION AND EPA RESPONSE eevee eeveeereee
A.
NRDC Petition seca c cece eer eceeeeenee
eaereerererocer ere eoee
B.
EPA Response ........
APPENDIX A List of Commenters .....ccsccecvvcvscces
APPENDIX B References .....ceccee
eoereseeeeerene
APPENDIX C Cross References ....
INTRODUCTION
In a December 19 1984 Federal Register notice the Environmental Protection Agency invited the public to comment on issues relating to a Natural Resources Defense Council petition to prohibit the use of asbestos in vehicle brakes This Comment Catalogue contains excerpts from letters received by the EPA in response to the Federal Register notice
The Comment Catalogue consists of five major sections and several
subsections as shown on the Table of Contents These sections were formulated after a careful review of the issues raised by the commenters
Included in the appendices are a list of commenters arranged by category a complete reference list of comments received and cross references showing where comments for each commenter can be located in the catalogue
The comments are numbered consecutively from 1 to 90. The reference for each comment is found after the comment itself and each comment is separated by a horizontal line
I. IDENTIFICATION AND RECOMMENDATIONS OF COMMENTERS
A. Trade Associations
The Asbestos Information Association America AIA a nonprofit organization whose member companies in the United States and Canada are involved in the mining and milling of asbestos and the
manufacturing and marketing of containing products welcomes the opportunity to comment on the Environmental Protection Agency's response to a citizens petition on asbestos which was
published in the December 19 1984 Federal Register
First AIA would like to reiterate the position taken in its earlier comments dated November 28 1984 on the petition to ban the use of asbestos in brakes Those comments argued that asbestos should not be banned for the following reasons
1 Ambient levels of asbestos and the small contribu-
tion of brake materials to those levels do not
represent an unreasonable risk to the public
2 The use of containing products does not
constitute an unreasonable risk to brake maintenance workers and in addition EPA should
defer to the Occupational Safety and Health Administration on workplace regulation
3 Substituting materials for which the health
effects have not been evaluated and whose use
is uncontrolled for asbestos which is highly regulated could result in greater health risks to the public and workers
4 A ban would be contrary to the international
consensus on the controlled use of asbestos
5 The NRDC petition to ban the use of asbestos in
brakes is not based on considerations of un-
reasonable risk as required by TSCA but rather on an approach which advocates a zero risk
standard for the statute
Returning to the particular case in point the Agency comtemplates
an action to ban the use of asbestos in brakes in favor of substi-
tute materials The economic effects of such action would be
certain and substantial The benefits
of health effects are speculative and they are of a magnitude that would not
of such an action in terms
uncertain not only because be detectable but also
because no consideration is given to the health effects of the sub-
stitute materials which have their own potential for harm Such
an action could not be considered to be a reasonable one and would
not be permitted under TSCA
Asbestos Information Association pp 1 2-3
The Friction Materials Standards Institute Inc. FMSI is a trade
association of twenty friction materials manufacturers in the United
States with associate Members worldwide The FMSI has read the petition submitted by the Natural Resources Defense Council NRDC to the Environmental Protection Agency EPA for the purpose of prohibiting the use of
asbestos in brakes for new cars and trucks and in replacement brakes in
existing vehicles
We wish to comment comment at this time on certain sections of the petition
While we are not now taking a position for or against said petition we believe it is important to submit the following comments Should it be
deemed appropriate these comments may be supplemented at a later date by a more depth critique We will refer to the sections as headed in the NRDC petition
Ar funmediate ban on the use of asbestos in passenger I and truck brar s cannot be supported because of the importance of safe brake systems on
the nation's highways Brake linings are a safety related product We
stress consideration of these facts
1 There are legitimate questions on the health hazards of
the fibrous substitutes suggested for asbestos replacement
.
in friction materials
2 There are programs in place by industry c eliminate the use of asbestos in friction materials and these programs realistically address health safety economic performance timing and materials availability issues
3 The industry must be given time to develop a total line of products
which will meet all highway
safety rerequqirements uirements safety
We believe the industry will accept a properly planned program pointed
towards the eventual elimination of asbestos in its products We urge that
EPA study the suggested substitute materials as well as the feasibility economic impact realistic necessity - if it exists and timing requirements appropriate to the elimination of asbestos in friction materials before re-
sponding to the petition or proposing a bon on the use of asbestos in
friction materials
Friction Materials Standards Institute Att 1 pp 1 4-5
3
I furnish herewith in triplicate the comments of the Japan
Automobile Manufacturers Association with the above captioned proceedings
Tokyo
Japan
in connection
Based on information received to date EPA is not prepared
to make an unreasonable risk finding for an immediate ban of all
uses of asbestos in brakes at this time
We consider this as an entirely reasonable judgment and agree to such and pay our respect to this
Taking into consideration the availability of substitute fibers it is expected that we will encounter difficulties if vehicles decide to adopt the
substitute materials It is recommended
that the action to prohibit the use of asbestos presently used as a major brake
component and the substitution use of a
asbestos brake friction material should-
be phased in smoothly over time granting
sufficient lead time at each stage
Japan Automobile Manufacturers Association Att 1 pp 1 5
The Motor Vehicle Manufacturers Association of the United
States Inc. MVMA is a profit trade association whose
dan
members produce more than 98 percent of domestically manufactured
motor vehicles and employ nearly 750,000 workers
We are pleased
to respond to the December 19 1984 Federal Register notice in
which the Agency invited the public to submit comments on issues
relating to the Natural Resources Defense Council asbestos
petition
Based on the available information MMVA urges EPA to continue its current strategy as outlined by the Office of Toxic Substances Asbestos Regulatory Program As outlined under the Toxic Substances Control Act TSCA the exercise of authority to regulate a substance under TSCA requires a balancing of societal costs and benefits In the context of the NRDC petition an immediate ban on this use of asbestos is not justified Rather the OTS regulatory plan to eliminate asbestos over a period of ten years as substitutes become available is appropriate
MVMA members are AM General Corporation American Motors
Corporation Chrysler Corporation Ford Motor Company General
Motors Corporation International Harvester Company M.A.N.
Truck & Bus Corporation PACCAR Inc Volkswagen of America and Volvo North America Corporation
Inc.
Motor Vehicle Manufacturers Association pp 1-2
B. Vehicle Manufacturers
In view of the controversy and the problems encountered with the development of asbestos substitutes Chrysler Corporation believes that it would be inappropriate to prohibit the use of asbestos in brake linings at this time Chrysler and we believe the other vehicle manufacturers are moving to asbestos brake lining materials as rapidly as technology will permit Any regulation will not increase the rate of this changeover and forcing the use of asbestos materials at a premature date could very well result in compromises in brake performance which are not in the interest of motor vehicle safety
In addition to these comments Chrysler Corporation participated in the
development of the comments submitted by the Motor Vehicle Manufacturers
Association of the United States
We endorse those comments and by reference
incorporate them as a part of our response
Chrysler Corporation p.3
Ford Motor Company is not in the brake manufacturing business We purchase all of our brake systems and parts both for the assembly of new vehicles and for the aftermarket from outside manufacturers and suppliers Whether the purchased in assembly parts are used in Company cars light trucks medium trucks heavy trucks agricultural tractors construction tractors or for the aftermarket all of the friction components -- be they pads or shoes -- are manufactured by others
In considering whether to regulate the use of asbestos in brakes
EPA must be sensitive to this crucial issue It would be neither
effective nor constructive for EPA to force the complete redesign of car and truck brake systems at enormous costs for currently vehicles or for production vehicles for which the consuming public rightfully expects that aftermarket parts will remain available for routine maintenance service at reasonable cost We thus strongly recommend that EPA not seek to regulate the use of asbestos in the brakes of vehicles which currently are being manufactured or which formerly were manufactured with containing brake systems
Ford Motor Company pp 1 2
IH's interest in this rulemaking stems from the fact that it is a
leading manufacturer of medium- and heavy trucks and buses in
the United States having these products Moreover
the largest share since the January
of the market for 1985 sale of IH's
agricultural equipment operations to Tenneco Inc. the company is now completely dependent on sales of trucks and medium diesel engines in North America
IH currently purchases from outside suppliers various components
containing asbestos
These include gaskets clutch facings
sealing materials and brake assemblies
Because IH is a
purchaser rather than a manufacturer of containing products it is extremely concerned about the possible effect that
a ban on use of products in motor vehicles would have on its
product planning and engineering
RECOMMENDATIONS
1
EPA should thoroughly analyze the health risk from exposure
to motor vehicle uses of asbestos to determine if such uses
present a health problem that must be addressed
On this
point IH supports the arguments of the Motor Vehicle
Manufacturers Association in its comments on this rulemaking
2
Any ban on use of asbestos in motor vehicle applications
should allow motor vehicle manufacturers sufficient lead time
to test and incorporate new materials into their products
3
In applications where satisfactory substitute materials are
not available either in production or aftermarket usage EPA
should allow exemptions from the rule
International Harvester pp 1 5-6
Renault agrees that certain a threat when released into
types of asbestos consist of fibers which pose
the atmosphere but the asbestos dust emitted
by wear of the brake linings is never found in this form Provided that
certain basic precautions are
especially during replacement
installer
taken the handling of asbestos brake linings
installation is also without danger to the
Renault USA Inc. p 2
C. Brake Manufacturers
The Highway Braking Systems Division of the BFGoodrich
Company is a producer of disk brake assemblies for loaders
scrapers and haulage vehicles
We
currently
purchase
individual components including brake linings
The prime
functions performed at the Highway Braking Systems Division
are metal component machining and assembly
With regard to the
brake linings which
use of asbestos contain asbestos
BFGoodrich currently uses but we perform no grinding
or machining operations to the asbestos containing linings
In summary BFGoodrich produces brake systems for a small
highly specialized market
The unique friction material
requirements of the highway market are satisfied for the
most part by asbestos
BFGoodrich is actively searching for
asbestos free substitutes at this time
Finding asbestos free
linings to evaluate is difficult due to low volume which causes lining vendors to concentrate their efforts in other areas There is no asbestos free lining material currently available
to replace asbestos linings
BF Goodrich Company pp 1 2
10. Motor Wheel Corporation a wholly subsidiary of The Goodyear Tire & Rubber Company is a major supplier and manufacturer of wheels and brake products for the passenger car truck and highway vehicle North American markets As
a manufacturer of automobile and truck brake drums we have
dynamometer testing experience with both asbestos and asbestos lined drums We have noted several areas deserving of comment and the Agency's concern prior to final rulemaking
Motor Wheel's testing is not extensive enough to formulate any final conclusions However we do recommend extensive testing be undertaken to decisively determine the effect of non-
asbestos life
linings on vehicle brake performance and brake drum
Motor Wheel Corporation pp 1 2
11. Rockwell International is a major manufacturer of foundation brakes for
heavy highway highway and military vehicles impacted by the above referenced subject The foundation brakes which incorporate purchased brake linings are supplied to the vehicle manufacturers who in turn integrate the brakes into specific vehicle models and vehicle applications These vehicles are utilized in the trucking construction mass transit and agricultural industries as well as by the U.S. Department of Defense Rockwell International is also a manufacturer of other allied heavy
vehicle chassis components such as axles brake drums universal joints and vehicle electronic monitoring systems
Rockwell requests that the EPA consider the following in any proposal of rulemaking
0 Establish a phase program for NAB lining based on eliminating the largest amount of asbestos in the best possible time frame
This should result in a stage process with the highway trucks and trailers representing 54 of the market as the first stage and where the earliest possibility exists for conversion to NAB lining
The second stage should consist transit coach brakes and wedge time will be required
of addressing the highway brakes
brakes where considerable additional
0 Provide adequate monitoring of NAB programs as they affect the ) vehicle manufacturers 2 brake manufacturers and 3 brake lining manufacturers for the complete range of on- and highway heavy vehicles before establishment of regulatory effective dates
0 Coordinate the regulations affecting transportation with other appropriate Federal Agencies principal of which are the Occupational Safety and Health Administration and the National Highway Traffic Safety Administration
It should be pointed out that the most critical test for NAB is the dynamometer requirements of the Federal Motor Vehicle Safety Standards Further any change to NHTSA Safety Standards can have a monumental impact when attempting conversion to new base brake lining materials
We feel the suggestions outlined will minimize the asbestos used and enable the vehicle industry to make the transition from asbestos to asbestos material in the most expeditious manner possible
In conclusion Rockwell emphasizes that any proposed rulemaking consideration
to eliminate or phase out the use of asbestos in the heavy vehicle
'
industry should recognize that unlike the passenger car industry asbestos
substitutes for the multitude of heavy vehicle applications are only
in the early stages of development Further the lining suppliers to this
industry are limited in number and development capacity
Rockwell International pp 1. 4-5
12
The Wagner Division of Edison International Inc.
Wagner is an assembler of brake products Wagner buys its
friction materials in accordance with performance specifications
from outside suppliers
We would strongly recommend that the EPA not regulate the use of asbestos as a component in brake lining for vehicles based upon the current knowledge available regarding substitutability and risks associated with asbestos in brake lining
Wagner Division Att 1 pp 1 6
D. Substitutes Manufacturers
13
We wish to call EPA's attention to the availability of and to the
possible use of low cost low modulus industrial grade carbon fibers as a
suitable substitute for asbestos in automobile and truck brakes
Ashland Petroleum Company p 1
14. In a data
recent copy of the Federal Register the above on substitutes for asbestos friction
petition requested products
Enclosed are articles written by Du Pont
asbestos friction products
We hope
the unaswered questions in the article
on customers who have develop these articles help clarify
Du Pont Canada Inc. p 1
15. These comments are submitted by Engelhard Corporation in response to a request by the Environmental Protection Agency EPA for information on asbestos substitutes in automobile and truck brakes Engelhard manufac tures EMCOR 66 mineral composition a very effective replacement for asbestos in friction products for automobile truck and railroad brakes EMCOR 66 is produced from American attapulgite which has been thoroughly tested and evaluated by independent researchers and has not been found to be associated with either cancer or fibrotic lung disease
In addition to discussing the performance of EMCOR 66 as a replacement for asbestos in friction products and the safety of American attapulgite we also wish to respond to the unsubstantiated inaccurate and highly misleading statements and allegations made by certain asbestos product representatives concerning alleged health hazards of asbestos substitutes
We have divided our comments into three sections Performance Character-
istics of EMCOR 66 Summary of Health Research Conducted Attapulgite and Response to Certain Previous Testimony
on American
Engelhard urges the EPA to question seriously asbestos product representatives serving allegations that asbestos substitutes have not received adequate testing and scrutiny or that attapulgite carries the same health
hazards as asbestos
Engelhard believes that American attapulgite has been thoroughly tested and evaluated and does not represent a hazard similar to that presented by asbestos and Engelhard has submitted these comments in order to clarify the record on American attapuglite In addition we hope that the informa-
tion presented here on the performance of EMCOR 66 as a friction material component in brake linings will reassure the EPA that feasible substitutes do indeed exist
Engelhard Corporation pp 1 6-7
16. Monsanto Company is developing Phosphate Fiber a novel
crystalline fiber form of calcium sodium metaphosphate The
physical properties of Phosphate Fiber suggest it will be
useful as a reinforcing fiber in friction materials and
other composite products
Monsanto Company p 1
E. Miscellaneous Commenters
17
I am deeply concerned at the Agency decision to grant the NRDC petition to begin an initiative to ban asbestos in brakes I do not believe that the Agency should take this step nor is there any reason
that it should
My concerns center on the safety of myself and my family if we are required to experiment with replacement brake materials until a satisfactory replacement is hopefully found someday It might be
different if there were some reason to believe that such a ban would have
a beneficial effect on some sector of
and the Agency has no supporting data benefit actually will occur
the for
public but there is
it to believe that a
no reason
measurable
The Agency has no data to support a decision to ban asbestos here or elsewhere There are no scientific facts to support that even a small portion of the estimated 19.2 lives would be saved if the proposed ban were inflicted In fact there is no scientific basis for the risk assessment methodology used to arrive at these estimates That methodology has been criticized by the courts the Science Advisory Board and a large segment of the scientific arena See the comments in response
to 49 FR 46294
There certainly is no assurance that any new forced substitution of materials would be better than 99.999 successful day after day year after
year
We urge the Agency to face up squarely to its responsibility to say
no when no is the correct answer and deny the petition to ban asbestos brake linings The safety of my children and my grandchildren depends on
this decision
John T. Barr pp 1 4
18
The Center for Environmental Health of the Centers for Disease Control has
reviewed the
211015
Proposed Rules on Use of Asbestos in Automobile which were published in the Federal Register on
and Truck Brakes December 19 1984
Volume 49 No. 245
A reduction in ambient air elimination of asbestos in
should be strongly weighed
asbestos levels should be encouraged but the brake pads as a means of accomplishing this goal against the safety performance of alternatives
Center for Environmental Health p 1
19 The members of the Classic Cars Of Ponca City Club are extremely concerned about the recent EPA plan to ban the use of asbestos in car and truck brakes As owners of antiques collectors and special interest automobiles dating back to the 1920's we strongly object to the use of semimetallic or aramid fiber brakes especially in our older automobiles which are not equipped with power brakes However we suggest that warning labels be placed on all packages containing asbestos brakes and proper instructions included in the packages on how to handle asbestos dust when replacing brakes Such precautions will minimize asbestos fibers ingestion in the lungs and eventually minimize lung cancer
Classic Cars of Ponca City p 1
19
II LEGAL AND POLICY ISSUES
TT
20
The Stratford Citizens Against Pollution is a local
independent responsible
this letter
environmental group comprised of reasonable
residents of both communities
The purpose of
is to express our legitimate concerns with
respect to ambient asbestos concentrations in our neighborhoods as well as to define the sources of these emissions and to endorse fully the citizens petition filed by the National Resources Defense Council to ban the use
of asbestos in brakes
Our group was formed nearly to the chronically poor air
two years ago in direct response
quality in our neighborhoods due
in most part to offensive and potentially hazardous emissions
from Raymark Corporation formerly Raybestos East
Main Street Stratford Raymark is a primary containing brake and gasket friction
manufacturer of materials and
one of the largest industrial users of asbestos in this state
The facility is located in the center of densely populated
residential areas of both communities
Contiguous to the
Raymark facility is the Stratford toll station on Interstate
95
Therefore in the absence of a viable
effective and comprehensive asbestos enforcement policy by
D.E.P. it would appear that the only alternative available
othe.
to protect our families and heighbors from the risks of
asbestos exposure be an immediate ban on the use of
asbestos in the manufacture of brakes
With the understanding
that economically and technically feasible as well as environ-
mentally suitable substitutes are available the Milford Stratford Citizens Against Pollution fully support an ~ immediate
ban on the use of asbestos in brakes
We breathlessly await E.P.A.'s decision
Stratford Citizens Against Pollution pp 1 2-3
A. EPA vs. OSHA as Regulatory Agency
21
In addition the only significant area where lives might possibly be
saved is within the venue of OSHA and EPA must abrogate Sec 9 of TSCA to
take authority there because OSHA already is acting on the problem
Thus EPA has no authority to act in this matter
John T. Barr p 4
EPA should
22
defer to the Occupational Safety and Health Administration on workplace regulation
Asbestos Information Association p 1
23
The FMSI concerns relate to plant regulations versus control of general public exposure to asbestos dust While one agency has proposed to tighten worker exposure to asbestos another is being petitioned to eliminate asbestos in friction materials The disparity between these two situations could well create implementation and economic problems for friction materials manufacturers If asbestos is to be regulated out of friction materials the manufacturers should not be saddled in the meantime with compliance to new tighter regulations of asbestos in the workplace The industry must know which direction regulatory activity will take
Friction Materials Standards Institute Inc. Att 1 p 2
B. Demonstration of Unreasonable Risk
24
Ambient levels of asbestos and the small contribution of brake materials to those levels do not
represent an unreasonable risk to the public
The use of constitute
containing products does not
an unreasonable risk to brake main-
tenance workers
The NRDC petition to ban the use of asbestos in
brakes is not based on considerations of un-
reasonable risk as required by TSCA but rather on an approach which advocates a zero risk
standard for the statute
Second AIA wishes to comment on a major omission in the December 19 response namely the complete absence of any mention of the potential health effects of substitutes for asbestos in brakes Any rational system of regulation in which the use of a material or substance may be prohibited for reasons related to an unreasonable risk of injury to health or the environment must include an evaluation of the risks resulting from substitute materials If this were not the case it would not be possible to say that any benefit had accrued to society as a result of a regulatory action
Section C of the Toxic Substance Control Act TSCA specifically cites that substitutes for a substance must be given consideration in the context of section 6 rulemaking
C the benefits of such substance or mixture for
various uses and the availability of sub-
stitutes for such uses
While it may be argued that a consideration of the availability of
substitutes does not necessitate a consideration of the health
effects of the substitutes the immediately following section which lists additional factors to be considered would require an evalua-
tion of substitutes health effects
D the reasonably ascertainable economic consequences of the rule after consideration of the effect on the national economy small business technological innovation the environment and public health
emphasis added
Section D is explicit in stating that the environment and public
health effects of a rule must be given consideration
If a sub-
stance is to be banned in favor of substitute materials Section 6
c D requires that the environmental and public health effects of
such an action be considere andd such consideration would have to
take into account the environmental and public health effects of
the substitute materials
Any other course of action would be ir-
rational and not permissible under TSCA
The entire Toxic Substance Control Act is framed within the context
of reasonable regulatory action It does not permit the regulation of any risk but only unreasonable risk The intent of Congress in passing the Act is specific on this issue Section c of TSCA
entitled Intent of Congress states
It is the intent of Congress that the Administrator
shall carry out this Act in a reasonable and prudent
manner and that the Administrator shall consider the
environmental economic and social impact of any
action the Administrator takes or proposes to take
under this Act
Returning to the particular case in point the Agency comtemplates
an action to ban the use of asbestos in brakes in favor of substi-
tute materials The economic
certain and substantial The
effects of such an action would be
benefits of such an action in terms
of health effects are speculative and uncertain not only because
they are of a magnitude that would not be detectable but also because no consideration is given to the health effects of the
sub-
stitute materials which have their own potential for harm Such
an action could not be considered to be a reasonable one and would
not be permitted under TSCA
Asbestos Information Association pp 1-3
) 25
OSHA now has an emergency temporary standard of 0.5 cc See 48 FR be reduced at some time in
51086 29 CFR 1910.1001
This will undoubtedly
let's use that value for now
OSHA has
the near future but again
concluded that at this new level 1.24 note the precision of the
estimate of the workers will develop asbestosis and 1.7 will develop
to some 25 who will die of cancer from other
cancer. This compares
factor of 10 for the thirds of
causes
and
includes
an
elevation
by a
All
in
all
it adds
up to about a %
the workers who smoke cigarettes
because of this exposure or
estimated increase in deaths of smokers
95
about 75 persons Of course OSHA uses the same exaggerated upper
limit risk assessment which EPA does and which is known to overestimate
the real value by multiple orders of magnitude see Hoel et al Science
219 1032 1983
However
let's
continue to play the game by your rules
workers after all those who have
Over the life of the next generation of are replaced the imposition of a ban
experienced past
higher
exposures the current OSHA exposure
limit
will
save
the
rather than reliance on
This is using the risk
lives of about 75 persons or about one per year
estimate made by OSHA to justify the present temporary standard and
assuming a lifetime exposure at the maximum level
Now look at the 550,000 mechanics thiEsntesrhloiunled hparsoduscteateadn tehxactessthelyung
are exposed at about 0.3 cc and that
No
of 0.375 See Session 1 p 28 in Banbury Report
cancer death rate of Occupational Cancer Peto and Schneiderman eds,
9 Quantification
1981. At the temporary OSHA standard this
wCooludldSpberinag 0H.a2r2b5or eLxacbeosrsataonrdy applied to 550,000 workers would be 18 lives
per year over 70 years in the next generation of workers
if EPA decides to throw aside Sec 9 of TSCA and use Sec 6 to
This
to brake linings a maximum of 19 lives per
ban
occupational
exposure time in
the
next century
would
be
saved
using
year starting some
methods of calculation
just for the sake of argument the agency's own
this risk seems to
Based on comments made in the NESHAPS rule on benzene
be too small to warrant Federal regulatory action 49 FR 23558
JAPCA national to aboutMoving now to the public at large the
ambient level of
asbestos largely natural is about 1.5 ng See Enterline
33 317 1983 Enterline says that this is a total cancer risk of 102 x
10
The EPA gives a range of risks for exposure to ambient fibers in
its Asbestos Health Assessment Update 8-84-003 table 6-1,2
Using the midpoint estimate for smokers there is a total added risk of
103 per 100,000 for a lifetime exposure
0.01 ml or 300
would females mto both males and
At 1.5 mg this
be
about 0.5 per 100,000 or
^ 10 '. This is about 7 ^ 10
per year
brake linings add
or 17 per year for the entire United States However
than % of this ambient asbestos according to the Notice so action _
less
by EPA
here will
save
0.2
lives
per year
beginning some time in the
the benzene test
next generation Certainly this does not pass
You will notice that we have used smoker data in these estimates
An employee may claim that the employer caused exposure to asbestos but no employee may claim that the employer required smoking cigarettes
The danger of smoking in general and in the presence of asbestos in particular is sufficiently well known that there is no excuse for an employer bearing the added burden of the risk caused by an employee's smoking
John T. Barr pp 2 3
III HAZARDS ASSOCIATED WITH ASBESTOS USE IN BRAKES
A. Epidemiological Evidence and Case Reports
26
Studies have demonstrated that individuals working with
insulation asbestos have five times the risk of acquiring lung
disease compared with the risk faced by the general population McDonald Malignant Mesothelioma in North America Cancer 1650-1656 1980 The McDonald study which reviewed occupational risks associated with malignant mesothelioma for 668 cases in North America recorded in the late 1960's and early 1970's reflected the following relative occupational risks compared to
matched controls
Insulation
46 X
Production and asbestos manufacture
6x
Heating trades Shipyards
Construction
x 3x 3x
Other Garage workers Maintenance
Transportation Industry
1x 1x 1x
The mortality study conducted by G. Berry and M.L.
Newhouse is also critical in weighing the risks associated with
the continued use of asbestos in brake applications
Newhouse
Mortality of Workers Manufacturing Friction Materials Using
Asbestos British Journal of Industrial Medicine 1983 1-7
The study conducted over the period 1942 to 1980 was carried out with respect to 13,460 workers of a factory producing friction
materials The only type of asbestos used was chrysotile except for two periods before 1945. The report concluded that Compared with national death rates there were no detectable excesses of
deaths due to lung cancer gastrointestinal cancer or other con-
cerns The experience at this factory over a 40 year period
showed that chrysotile asbestos was processed with no detectable
excess mortality
Wagner Division Att 1 pp 4-5
27
The introduction of the NRDC petition emphasizes that the
link between asbestos exposure and cancer has been conclusively
demonstrated by epidemiologists since the early 1950's While this may be true for certain occupational exposures of sufficient length and quantity no association has been demonstrated between
exposure to brake dust and cancer
There is no evidence in the medical
literature demonstrating any significant risk from either brief or term exposure to friction products
D.
Automobile Maintenance Workers Are
At Particular Risk From Exposure To
Asbestos Brake Products
This section argues that because of the airborne
mobility of these small asbestos fibers from brake linings a diverse group of people are at risk The
petition includes garage mechanics bystanders tool
booth operators families of mechanics and persons
living in urban environments as the population at risk
The
are
only two
two case
mesothelioma
citations upon which this argument is based
reports which purport to in a pet whose owner was
document a
a mechani1c5
and
a brake mechanic's latter case is not footnote indicates
child who had mesothelioma
a published case report but the
that this was communicated in a
The
letter from Barry Castleman to a person or persons
unknown One case report of a pet and a letter from Barry Castleman are scant support for the sweeping
statements made in this section
This section concludes by alleging that recent
literature also documents mesothelioma among automobile
repair workers Greenberg's 1974
The first report 17
literature cited is which found one mesothelioma
death in a motor mechanic Greenberg gives no
occupational history for the mechanic
The other case report cited is that by Langer in 1982 Support for the proposition that there are two additional mesotheliomas in brake mechanics is allegedly found in Castleman's recent book on asbestos and a
personal communication by Susan Daum to Castleman Yet important data on these cases are missing such that verification is not possible from these sources
alone
Thus there are only two cases of mesothelioma in all of the reported medical literature which allegedly implicate brake dust One of those Greenberg is questionable
Motor Vehicle Manufacturers Association Att 1 pp 1 2 4-5
28
The Institute does not have epidemiological data to challenge the evidence associating asbestos with lung cancer and mesothelioma We do wish to point out however that the most complete study of the linkage of asbestos
to cancer in a friction materials factory concluded that there was no incidence of lung cancer in the friction materials cohort so exposed
that any incremental occurrences of mesothelioma were demonstrated in
higher
and those
exposed also to crocidolite asbestos
Motor Vehicle Manufacturers Association Att 4 p 2
B. Health Effects of Chrysotile Fiber vs. Other Fiber Types
it Chrysler
Corporation
recognizes
the
fact
that
exposure
to
certain
levels of the
29
be a health risk However is generally agreed that
asbestos fiber can is
on the type of asbestos fiber The only type used in
degree of risk
dependent
which has been shown to be the
the manufacture of brake linings is chrysotile
least hazardous of the various asbestos forms
Chrysler Corporation p 1
30
We would also like to point out that the statements by
NRDC regarding the risks associated with asbestos fail to take
into account the distinction between insulation asbestos which
is not involved in brake application and chrysotile fibers which
are
Wagner Division Att 1 p 4
31
While
is
.
a demonstrated
human
carcinogen
that
that asbestos
evidence exists that
cancer and other lung disorders
of different forms of asbestos varies substantially
it is known causes lung
the toxicity
Two
studies
both of which
entail extensive surveys of in the toxicity of various
current literature Bfootuhnd foduinfdfercernocceisdolite to be the most toxic
forms of asbestos
We have included the comments
and chrysotile to be the least
of asbestos should be
made to OSHA because ditfhfeeroivnegraltloxiecviatliueastion of the risk posed by
considered as part of
exposure
Motor Vehicle Manufacturers Association p 2
32 The assertion is made that animal inhalation studies
demonstrate no significant difference in the effects of
various types of asbestos NRDC cites a 1974 study by
Wagner as authority for that statement The petition
subsequent neglects to point out that numerous
experiments including the work of Gross
4,5
animal
demonstrate precisely the opposite These latter
studies
type of
would tend to asbestos used
indicate that in brakes is
chrysotile the only significantly less
pathogenic than other types of asbestos fibers
Motor Vehicle Manufacturers Association Att 1 p 2
33
Chrysotile asbestos is the only asbestos type used in brake linings manufactured in the United States We
are aware of only one manufacturer using anthophyllite in a specific clutch
application To the best of our knowledge crocidolite and amosite are not used by any United States manufacturer of friction materials A most graphic illustration of the lack of lung cancer for the friction materials manu-
facturing cohort is shown in publication of the Newhouse paper in the British Journal of Industrial Medicine Mortality of Workers Manufacturing
Friction Materials Using Asbestos Refer to the Newhouse report cited as Ex 84-021 in the Emergency Temporary Standard page 51114 of November 4 1983 FEDERAL REGISTER
Motor Vehicle Manufacturers Association Att 4 p 2
34
A.
OSHA Should Recognize Differences in the
Toxicity of Various Forms of Asbestos
The proposed OSHA standard would adopt either a 0.2 or a 0.5
fibres per cubic centimeter cc permissible exposure limit
PEL for all forms of asbestos Substantial evidence exists that
the toxicity of different formosf asbestos varies substantially
In March 1976 the British Health and Safety Commission formed an advisory committee on asbestos with the following
charge
To review the risks to health arising from exposure to
asbestos or products containing asbestos including persons
exposed at work members of the public exposed to asbestos
generated from work activities members of the public exposed to asbestos from consumer products and from asbestos
waste to make recommendations as to whether any further
protection is required The Committee's report would be for
the consideration of the HSC and Ministers and would be
published 1
The advisory committee conducted an exhaustive study surveying existing literature and soliciting the testimony and reports of experts in fields related to asbestos
The final report of the advisory committee discussed the relative potency of various forms of asbestos in producing lung
cancer in man
Evidence in man about the relationship of fibre type to lung cancer is inconclusive but where it exists it indicates that exposure to amphiboles crocidolite or amosite or to mixtures with chrysotile rich in them has been more dangerous than to chrysotile or anthophyllite alone Table 15 However as important gaps in our knowledge of this aspect of the field remain unanswered the weight which
can be attached to this conclusion at present is limited
The referenced Table 15 appears in this comment as Figure 1.
Concerning asbestosis in man the advisory committee's
report states Quantitative evidence about impairment of lung function in man in relation to fibre type is limited to one study which
suggests that crocidolite may have been more harmful than
chrysotile 3
FIGURE 1
per cu ft Table 15 see Vol 2 Table 21
Relative risk of death from correctedcor ected for differenceisn
cancer by type of fmiiblrleion particlesparticles
years After
respiratory cumulauve dust exposure in
Enterline and Henderson 1973
Type offibre
Respiratory
cancer deaths
Average
cumulative
dust exposure
Relative risk
adjusted for
cumulative
dust exposure
=
330
272
Amosite only
39
244
272
Chrysoule only
Amosite chrysotile
am
266
272
Chrysoule and
10
crocidolite
Amosite chrysotile
and crocidolite
2922
208
22
273
22
2922
Any amosite
Any chrysotile
2922
Any crocidolite
2922
286
22
244
22
229
:
Concerning mesothelioma in man the report states
As far is mesothelioma is concerned evidence from miners
from process workers exposed to a single fiber type from the distribution of neighbourhood and domestic cases and from the geography of mesothelioma when combined presents a powerful case from four different sources that crocidolite has been more dangerous than chrysotile and anthophyllite
The position of amosite may be intermediate between
crocidolite and chrysotile 4
In addition to these findings the advisory committee recommended control limits for various types of asbestos as
follows chrysotile cc amosite cc and
crocidolite cc In addition the advisory committee recommended a statutory ban on the importation of raw crocidolite
fiber.5
More recently the Canadian Province of Ontario formed a commission similar to the British Advisory Committee to investigate the health consequences of asbestos The Commission
established in April 1980 went to great lengths in its comprehen-
sive evaluation of asbestos This involved by way of illustration either personally or through their staff visits to Quebec
asbestos mines to the Mount Sinai School of Medicine in New York to Ontario manufacturing establishments and to asbestos removal
projects In addition it undertook a research program which
yielded two background papers and ten length research studies Testimony alone before the Commission produced 8,378 pages of transcript and the Commission's report comprises three
volumes in excess of 900 pages
Among the conclusions of the Commission were the following
4. There is strong evidence that crocidolite and amosite
fibres tend to be more hazardous than chrysotile fibres primarily because they are more likely to conform to the most hazardous length and diameter and secondarily because they are more likely to become airborne and hence to be
respirable It is also possible that crocidolite and
^mosite are more hazardous because of their chemical compo-
sition but this possibility rests in the realm of speculation
5 All fibre types can cause all asbestos diseases but mesothelioma is most likely to result from crocidolite exposure has a strong association with amosite exposure and has a weak association with chrysotile exposure
III
6. Whatever their type the likelihood that asbestos fibres
of the most hazardous dimensions are respirable is strongly a function of the individual process in which asbestos is being used Thus for example the manufacturer of brake linings which involves drilling and grinding is much less likely to generate fibres of hazardous dimensions than textile manufacturing which involves spinning and weaving 6
Elsewhere the report states
On the basis of this analysis we conclude that we cannot condone any manufacturing activity that involves the use of crocidolite or amosite asbestos The use of these two types of asbestos in Ontario should therefore be prohibited indefinitely As for chrysotile it is necessary to distinguish the industrial processes in which asbestos is
|
being used The control limit that the Regulation Respecting Asbestos currently applies to all chrysotile processes is 1 cc If this control limit is rigorously observed so that at the level of an hour weighted
average it is rarely exceeded we calculate that the
average level of exposure to which workers will be subjected is no greater than 0.5 cc Our data base permits us to calculate the disease risk encountered by workers in the following industrial processes mining and milling general
manufacturing excluding textiles and cement products
III
textile manufacturing and cement products manufacturing We find in the cases of chrysotile mining and milling and of general chrysotile manufacturing that the disease risk associated with chrysotile exposure under a 1 cc control limit effectively enforced involves a projected mortality rate well below the mortality rate that results from
industrial accidents in all Ontario manufacturing It
therefore falls well within the bounds of societally acceptable industrial risk
Thus these two comprehensive studies both of which entail
extensive surveys of current literature found differences in the
toxicity of various forms of asbestos Both found crocidolite to be the most toxic and chrysotile to be the least
These same conclusions are reflected in foreign occupational
health standards studies This is apparent if one refers to
Permissible Exposure Limits of Foreign Countries in 1983
Table 2 in the preamble to the proposed OSHA standard 49 FR
14135 Britain Finland Ontario Canada Sweden and the
European Economic Community all have
which apply the most stringent limit
occupational health standards
to crocidolite and the most
lenient to chrysotile
Motor Vehicle Manufacturers Association Att 2 pp 1-6
C. Asbestos Release from Brakes - Properties Amounts and Toxicology
35
Renault agrees that certain
a threat when released into
types of asbestos consist of fibers which pose
the atmosphere but the asbestos dust emitted
by wear of the brake linings is never found in this form Provided that
certain basic precautions are especially during replacement installer
taken the handling of asbestos brake linings installation is also without danger to the
Renault USA Inc. p 2
.
36
the physical
and chemical
characteristics
Moreover there is evidence that
of the material released to the
atmosphere as brake linings wear are not asbestiform in nature
Research
conducted by the National Institute for Occupational Safety and Health NIOSH has
indicated that this material is predominantly a thermally degraded compound and is almost entirely fibrous Until there is better evidence that the material
released the EPA
during
should
braking is indeed asbestiform in impose a regulation prohibiting
naturwee do not believe that
the use of asbestos in motor
vehicle brake linings
Chrysler Corporation p 1
37 Health Risks From Asbestos Brake Products
This section begins by asserting that brakes create substantial exposures to asbestos which constitute a serious health threat not only to brake workers but to the general public No scientific basis is referenced
for this broad statement
The petition asserts that numerous studies have shown
that a fraction of process The reader
asbestos fibers survive the
of this sentence might draw
braking
the
conclusion that this fraction is a significant one
The petition neglects to indicate that the three
principal studies the subject indicated precisely the opposite Anderson found less than .02 percent of
the fibers survived the friction process Lynch found less than 1 percent and Jacko found less than .3
percent More than 99 percent of the formed in the friction process into
nonfibrous dust
fibers are transa nonasbestos
This section stresses the
ambient air particularly
levels are increasing A
danger of asbestos fibers in
in urban areas where asbestos
private letter from Dr. Wm
Nicholson of Mt. Sinai New York City is cited as
authority for the proposition that
asbestos content in ambient air is
this from
increased automobile
brakes This conclusion is not based upon any published
evidence In fact there are several references
,
which indicate that less than 1 percent of asbestos
fibers in city core districts originated from disc brake
wear
The petition discusses the Jacko Bendix study 9 and cites it for the proposition that American vehicles release approximately 158,000 pounds per year of asbestos into the atmosphere This misrepresents Jacko's findings 158,000 pounds represents the total estimated asbestos emissions potentially produced from brake linings by the friction process Only 3.2 percent or 5,060 pounds of that was found by Jacko to
be airborne asbestos fibers 85.6 percent of the asbestos emissions do not remain suspended and dropout
from the atmosphere
This section goes on to discuss Rohl's 1976 study on
the asbestos content of brake dust
It notes that Ronl
found that more than 80 percent of the surviving fibers
were 0.4 micron in length but fails to mention that
such short fibers are considered by many
medical authorities not to be pathogenic
respected
at all 11
12
12
This section of the petition concludes with the sentence that the problem of exposure to dangerous levels of
asbestos during brake servicing is substantial and that he small asbestos fibers from brake wear can easily
penetrate throughout the respiratory system and also
migrate to other organs in the body
The conclusion is not supported by studies which indicate that the smaller fibers present during brake servicing are less likely to be deposited in (the10 lu1n1g
and macrophages more likely to be removed by
Motor Vehicle Manufacturers Association Att 1 pp 3-4
38
II
RESEARCH DATA AVAILABLE IN JAPAN ON ASBESTOS FIBER DENSITY
The results of research into the asbestos fiber density in
the atmosphere are reported in the U.S. Similar research has
also been carried out in Japan One representative study which
has been released to the public is that carried out by the JAPAN
AUTOMOBILE RESEARCH CENTER
This study measured the asbestos fibers content in worn powders by means of a bench brake test It complements test results already conducted on 142 samples for general
environmental conditions and the labor environment The results
are as follows
a
The asbestos fibers content in the brake is
60 Gravity ratio while that in worn
powders is 0.12 Gravity ratio
b
The asbestos fiber density in the atmosphere
under general environmental conditions
indicates a density of 0 - 0.46 pieces
The measurements were obtained in the
following areas intersecting points in Tokyo
metropolitan city at tollgates on highways and other general urban districts The
asbestos fiber density in the labors
environment indicates a density of 0.27
TTT 10
pieces which represents a close approximation to the general environment although it is concerned only with one repair
shop The asbestos density in the environment obtained in this study indicated a very low value when compared with that of an
asbestos density standard in a dusty environment 2000 pcs
Director of Labor Standard Bureau No. Circular 408 Therefore
it is concluded that under those circumstances no serious
problems exist
The asbestos fibers mentioned represent fibers with a length greater than Sum and have a length to diameter ratio equal to or greater than 3 to 1
Japan Automobile Manufacturers Association Att 1 pp 1-3
III
39
The use of asbestos in brakes may result in higher levels of
asbetos fibers in the ambient air
Asbestos is a demonstrated human carcinogen causing lung cancer if the human being exposed to it is not adequately protected
Classic Cars of Ponca City p 1
40.
In their report Monitored Asbestos Concentrations in Connecti-
cut Bruckman and Rubino describe an ambient air asbestos
survey which was conducted between 1974 and 1977 order to
define the magnitude of the health hazard posed by
asbestos fibers in Connecticut
The report cites
airborne a fold
increase in the asbestos mesothelioma incidence rate
in Connecticut since 1940
The data was collected in an
effort to promulgate a numerical standard for ambient asbestos
concentrations since in the judgment of the Connecticut
D.E.P. a no visible emission asbestos air quality standard
does not provide the State's residents with an adequate degree
substance of protection from this carcinogenic
the proposed numerical standard of 30
ng
was
Incidentally never promul-
gated
Bruckman
10 ng
and Rubino reported
urban and rural
day average values below locations removed from known
stationary sources of asbestos emissions
However near
each of the industrial users of asbestos values above
30 mweredetected
For the three toll stations moni-
tored those two removed from industrial asbestos users were
elevated 10-25 m , but the Stratford toll station showed
a day average of 41 ng with traffic nearly identical
to one of the other toll stations monitored
Certainly the
heightened asbestos concentration at the Stratford toll cannot
be attributed only to braking vehicles In their report
Bruckman and Rubino noted that this highest measured con-
centration for the entire survey was recorded at the monitor-
ing site located adjacent of the largest industrial
to an users
urban toll station of asbestos in the
and one state
Raymark has been cited three times in the past eighteen months
by Connecticut State Department of Environmental Protection
personnel for asbestos emissions violations of the Federal
N.E.S.H.A.P. Amendment to the Asbestos Standard
Copies of
these notices of violation are enclosed for your information
Inasmuch as our group contends as do Bruckman and Rubino that the Federal asbestos standard of no visible emissions
to the unaided eye is inadequate to protect the public then
certainly repeated asbestos emissions violations by Raymark comprise a tangible threat to the health of all residents living in the vicinity of Raymark's manufacturing facility These periodic visible asbestos emissions violations in conjunction with not visible fugitive dust emissions which most certainly occur as a result of poor maintenance careless handling procedures and innate efficiency restrictions on Raymark's dry dust collection system combined with airborne asbestos fibers resulting from braking vehicles at the
Stratford tolls expose residents of Stratford and Milford to an unreasonable even dangerous degree of risk
Stratford Citizens Against Pollution pp 1-2
TIT22 TIT22 TIT22
IV SUBSTITUTES
<++
A. Emcor 66
1 Applications and Performance
41
Engelhard manufac-
tures EMCOR 66 mineral composition a very effective replacement for asbestos in friction products for automobile truck and railroad brakes
PERFORMANCE CHARACTERISTICS OF EMCOR 66
For the friction industry more than just the health and safety aspects of asbestos are motivating asbestos substitution Although any substitute used must also be proven to be safe improved performance is another key issue Driven by pressure to reduce component weight and size automobile manufacturers are designing braking systems lighter and smaller As a
result the friction surface must withstand higher application pressures
and temperatures
Engelhard manufactures EMCOR 66 ultra fibers with the specific requirements of the friction industry in mind EMCORfi66 ultra
fibers offer a lower volatile matter content than asbestos and therefore
offer greater heat stability The oil absorption of EMCOR 66 is equivalent to the grades of asbestos used in friction compounds The abrasion and hardness rating of EMCOR 66 Moh hardness -- which should be lower than that of the metal surface on which the brake lining engages is lower
than virtually all other including asbestos Unlike
organic components in friction compounds
some other substitute materials EMCOR 66 does
not cause high noise levels or unusual brake wear
Engelhard Corporation pp 1-2
2 Commercial Availability
42.
Present reserves of American attapulgite are sufficient to meet market
demand for use in brake systems for at least the next 40-50 years There-
fore a consistent term supply of this material should be available to the friction industry
Engelhard Corporation p 2
TIT
2
3 Cost
43. Finally it is less expensive than other substitutes
Engelhard Corporation p 2
4 Health Effects
44. SUMMARY OF HEALTH RESEARCH CONDUCTED ON AMERICAN ATTAPULGITE
SUMMARY SUMARY OF HEALTH
RESEARCH
CONDUCTED
Background
American attapulgite is a sorptive mineral which has been mined and
processed
has been
in and around Attapulgus GA since 1920. American used commercially for over 60 years in a wide
attapulgite variety of
applications including as an adsorbent and thickening agent and recently
has been introduced as a replacement for asbestos friction materials
American attapulgite is composed of ultra fibers Samples of American attapulgite were analyzed for particle size by the National Institute for Occupational Safety & Health NIOSH and found to have an
average length of only 0.5 micrometers um In fact over fifty
percent of the particles were found to be less than 0.4 km in length The
very longest single fiber measured was only 2.5 ...m
In contrast material from some other parts of the world which have similar
chemical composition and crystalline structure have dramatically different
particle morphologies and in particular substantially greater particle lengths For example attapulgite from Torrejon Spain was found to range between 2 and 8 ...m in particle length with an average length of 3.5 ...m In addition 62.5 percent of the Russian material called palygorskite after the Ural mining district where it is located was shown to be longer than
2 ...m30 percent of this material was found to be longer than 5 ...m
To our knowledge all attapulgite used in this
processed domestically in and around the town of fore all attapulgite encountered in the U.S. is
country is
Attapulgus composed of
mined and GA Therevery short
particles similar to those which were studied by NIOSH As many prominent scientists as well as government agencies believe that the potential
health hazard of a fibrous material is determined by the number of long
particles
on other
longer than 5 ...mpresent in the material any health research longer materials is applicable to either American attapulgite
or the American environment
TIZ A
Health Effects Research on American Attapulgite
NIOSH has been conducting both mortality and morbidity studies of American attapulgite workers since 1975. Its research has involved more than 2,300 workers mining and processing attapulgite since 1940. We understand that
reports of these studies will be issued within the next 12 months NIOSH
has informally advised Engelhard Corporation that exposure to its attapulgite was not found to be associated with either cancer or fibrogenic lung disease and that there was no relation between pulmonary function and
cumulative dust exposure
In addition the research of eminent American and European scientists conducting independent experiments on laboratory animals and cell simulations have been reported to confirm that American attapulgite is neither carcinogenic nor fibrogenic For example Stanton's animal implantation work showed that the rate of tumorigenesis for two samples of American attapulgite was not different than that for negative controls
More recently Prof. Pott of the University of Dusseldorf Medical Institute for Environmental Hygiene who has studied Russian palygorksite French attapulgite and American attapulgite has shown that only the long Russian palygorskite was tumorigenic in laboratory animals The American and French attapulgite both of which are short were found not to be different than the negative controls Although this information has not yet been published Dr. Pott has provided the results of his research on American attapulgite to NIOSH and is committed we understand to publishing these
results in the near future
Further in evaluating a life span animal 1 percent and 3 percent attapulgite Prof. Toxicology in Heidelberg West Germany evidence that attapulgite was carcinogenic
feeding study using mice and
D. Schmahl of the Institute of
concluded that there was ----
Looking at the in vitro effects Lipkin of the National Cancer Institute
studied the effect of French and American attapulgite on macrophage
cells Using several samples of attapulgite Lipkin found the results to
be uniformly negative i.e. there was no evidence of cell toxicity as
measured by reduction in cell number over a hour period in any of his
experiments
He has also shown that this cell model correlates well
with the in vivo studies conducted by Dr. Merle Stanton
Likewise Woodworth Mossman and Craighead of the University of Vermont who studied the ability of attapulgite and other minerals to cause metaplastic changes in the tracheal mucosa of the Syrian hamster found American attapulgite not to be statistically different than negative
controls
In sum the available epidemiological and experimental data concerning potential health effects of American attapulgite all of which was developed by researchers independent of Engelhard uniformly indicates that American attapulgite is not carcinogenic or tumorigenic and does not cause pulmonary dysfunction
TIZ
Based upon the foregoing discussions on the effectiveness and safety of one asbestos replacement we believe that testimony to the contrary presented by certain individuals is unsubstantiated incorrect and very misleading In particular we take great exception to the comments of Mr. E.W. Drislane of the Friction Materials Standards Institute Inc.
On Page 3 of a letter to the made the following statement
EPA
dated November
13
1984
Mr.
Drislane
Sufficient data is not materials to state that
place environment or to
available at this time on the
they do not pose a hazard in the general public
substitute the work-
As discussed earlier this statement is simply not true for American attapulgite
On the same page of his letter Mr. Drislane quotes a reference from the 1984 Report by the Royal Commission on Matters of Health and Safety Arising
From the Use of Asbestos In Ontario.8 That quote as well as other
sections of the Royal Commission's report clearly reaffirms the wellrecognized concept that hazards of asbestos are related to particle length longer than 5 ...m As discussed here earlier American attapulgite is composed entirely of particles much shorter than this minimum critical
length
A second quotation referenced by Mr. Drislane which was made by Dr. Pelnar of the Institut De L'Amiante The Asbestos Institute in Quebec Canada alleges that attapulgite is one of several fibrous materials which contain fibers longer than 8 ...m and which have caused mesothelioma in laboratory
animals This is a reference to Dr. Pott's 1974 study of Russian palygorskite - a much longer fiber material of no commerical value -which cannot be associated with American attapulgite As discussed earlier Dr. Pott's more recent study with American attapulgite demonstrated that Engelhard's material does not cause mesothelioma
Therefore we believe that Mr. Drislane's conclusion that There are
legitimate questions on the health hazards of the fibrous substitutes suggested for asbestos replacement in friction materials is unsubstantiated and highly misleading Engelhard Corportion urges the EPA to seriously question the validity of these remarks
Likewise in a letter submitted to the EPA by Dr. Arthur M. Langer dated December 7 1984 Dr Langer asks Where are the data to show that substitute friction product materials are safe From the information supplied earlier we believe this data does indeed exist for American attapulgite
IV
Another inaccuracy is contained in a letter dated November 28 1984 in which B.J. Pigg submitted to the EPA comments by the Asbestos Information Association AIA On Page 20 of these comments the AIA states that the Danish government has established an fiber regulatory standard to assure that any fiber use is closely controlled Dr. Schaich Fries of the Danish National Institute of Occupational Health has informed Engelhard that the Danish Government does not in fact consider our attapulgite a fiber regulated similarly to asbestos We hope the EPA will recognize this distinction as well American attapulgite does not share the hazardous
properties of asbestos
CONCLUSION
Engelhard urges the EPA to question seriously asbestos product representatives serving allegations that asbestos substitutes have not received adequate testing and scrutiny or that attapulgite carries the same health
hazards as asbestos
Engelhard believes that American attapulgite has been thoroughly tested and evaluated and does not represent a hazard similar to that presented by
asbestos and Engelhard has submitted
the record on American attapuglite In
tion presented here on the performance
these comments in
addition we hope
of EMCOR 66 as a
order to clarify
that the informafriction material
component in brake linings will reassure the EPA that feasible substitutes
do indeed exist
Engelhard Corporation pp 2-7
Experience
45
EMCOR 66 ultra fibers have been evaluated purchased used commer-
cially and recommended by firms worldwide that produce either friction compounds or raw materials for the friction industry There are several firms in Europe that actively purchase and use EMCOR 66 in automotive
friction compounds In the United States Friction Company Incorporated Trenton NJ has approved 2 containing EMCOR 66 ultra fibers for a Ford
Division Products
friction compound Motor Company OEM
Original Equipment Market automotive brake Chemicals Incorporated Schenectady NY a leading resins to the friction industry recommends EMCOR 66
lining Schenectady supplier of phenolic
ultra fibers to
its customers Manufacturers of such diverse friction products as friction
papers for heavy equipment wet brakes and elevator brakes have approved and
now purchase EMCOR 66 ultra fibers
Engelhard Corporation p 2
IV
B. Phosphate Fiber
TV8
1 Applications and Performance
46. Monsanto Company is developing Phosphate Fiber a novel
crystalline fiber form of calcium sodium metaphosphate The physical properties of Phosphate Fiber suggest it will be useful as a reinforcing fiber in friction materials and other composite products We have introduced Phosphate Fiber samples to the worldwide friction industry for the purpose of evaluating this product's effectiveness and market potential While these evaluations are still in
progress early indications
prove valuable as a full or
in brake compounds
are that Phosphate Fiber will partial replacement for asbestos
EFFICACY IN FRICTION MATERIALS
Monsanto has developed and tested prototype friction compounds containing Phosphate Fiber In addition friction material manufacturers around the world have completed some of the evaluative studies required to prove the cost effectiveness of Phosphate Fiber in brakes Manufacturer testing has included bench and pilot scale compounding trials bench performance tests ( on so called Chase or FAST machines full scale dynamometer evaluations and performance trials using instrumented test automobiles This work has demonstrated the following performance advantages for friction materials containing Phosphate Fiber
- Compound Processing
Phosphate Fiber compounds are easily processed using typical existing manufacturing equipment The fiber is compatible with the full range of friction compound ingredients It is homogeneously dispersed in the finished compound resulting in low performance variability among batches
- Thermal Resistance
Phosphate Fiber maintains fibrous morphology and its native properties up to a temperature of 740 C 1365 F It is therefore more thermally stable than glass fiber aramid fibers and chrysotile asbestos Phosphate Fiber should provide reinforcement in the brake compound even at the higher temperatures experienced under severe braking conditions
- Durability
Friction materials containing Phosphate Fiber exhibit excellent cured strength and acceptable uncured or . green strength Brake durability in the tests completed to date has been adequate
- Friction Performance
Brake compounds made with Phosphate Fiber have exhibited friction levels in the desired range friction coefficients between .2 and .5 More importantly the friction coefficients of these compounds are stable over a broad temperature
range and show controlled fade at elevated
temperatures
Monsanto Company pp 1-4
2 Commercial Feasibility Availability
47 Monsanto operates a pilot facility for the purposes of process development and production of typical Phosphate Fiber samples to support industry evaluations Pilot plant capacity is adequate for satisfying initial market development requirements A larger interim commercial Phosphate Fiber plant is proposed for 1987 or 1988. This plant will be located in the United States and will have production capacity of up to 5 million pounds per year As market demand for Phosphate Fiber grows we plan to make additional investments in worldwide capacity
Monsanto Company p 2
10
3 Cost
48 Monsanto's pricing plan for Phosphate Fiber is not formally established However we estimate that Phosphate Fiber market price will be in the range of $ to 2 per pound Interim commercial product price will fall in the upper end of this range As this business grows Phosphate Fiber price will tend toward the lower end of this range
Monsanto Company p 2
4 Health Effects
49 Phosphate Fiber is composed of polyphosphate chains Polyphosphates are known to be hydrolyzed in living systems via enzymatic mechanisms While the Phosphate Fiber product contains some fibers in the respirable size class these fibers should be hydrolyzed by living cells Thus Phosphate Fiber should exhibit important health advantages compared to other biologically durable organic and inorganic respirable
fibers
Monsanto is undertaking an extensive biological testing program prior to full commercialization establish that the health safety risks associated with Phosphate Fiber are acceptably small The main tests included in our safety as-
sessment program are
- 2 Year Intrapleural Implant in Rats
- 2 Year Chronic Inhalation in Rats - 6 Month Tracheal Instillation in Rats
Monsanto Company p 2
TIZ
11
C. Carboflex IV
1 Applications and Performance
50
We wish to call EPA's attention to the availability of and to the
possible use of low cost low modulus industrial grade carbon fibers as a
suitable substitute for asbestos in automobile and truck brakes
Carbon fibers have been evaluated and are being used in brake
applications for aerospace military and commercial aircraft racing cars
road vehicle and industrial and now to some extent in automotive uses in
proprietary formulations Here carbon fiber properties of high strength
wear resistance good frictional properties good binding qualities high conductance high thermal stability oxidation resistance and low weight them most attractive carbon fiber composites are considered the
good
heat
make
material brakes of choice for high performance military and commercial aircrafts
Ashland's contacts in brake manufacture also indicate that carbon fibers
can and are competitive to an extent with asbestos performance and that neither retooling or special processing techniques would necessarily be required to permit substitution of carbon fibers for asbestos
Ashland Petroleum Company pp 1 2
51.
Carbon fibers are materials currently used in a number of industrial
applications calling for high strength and low weight Examples of its use today include graphite tennis rackets golf clubs and aircraft parts However growth of this market has been limited by the cost of producing high performance fibers used in these applications
Ashland's carbon fibers are produced at considerably lower cost
and are intended for general applications where specifications are less severe This production breakthrough should help the market
expand
1313
Anticipated new markets for general purpose fibers include fillers for polymers engineering plastics brake linings high temperature thermal and sound insulation other temperature applications replacing
asbestos automotive parts construction materials carbon
fiber composites and a variety of military applications
Ashland Petroleum Company Att 1 pp 1-2
2 Commercial Availability
52
Ashland presently has the capability of producing 30 year of general
purpose carbon fiber GPCF and will expand production to 100 year in the
fall of 1985
Ashland Petroleum Company p 1
3 Cost
53
Ashland's carbon fibers are marketed under the tradename
lengths CARBOFLEX range in price from 10 to 12
nonwoven mat chopped 1/8 to 1/2
per pound and come in the forms of , and ground or milled 100 to 400
microns average length
In the past the unavailability of low cost fibers has been a deterrent to their exploitation in automotive brake applications although in brake pad formulations we understand that the amount of fiber is rather low in composition Because we manufacture a proprietary raw material from which we produce our fiber and which is sufficient to produce up to 50 million pounds per year of fiber the potential exists for an even less expensive fiber if produced in much large volumes Ashland is dedicated to a continuing effort of further improvements in cost performance so as to enhance the effectiveness
of carbon fiber
Ashland Petroleum Company p 1
D. Kevlar Aramid
1 Applications and Performance
54
Kevlar was first introduced by E. I. du Pont de Nemours & Company in 1972 with an initial investment commitment of more than 500 million U.S. followed by a 200 million U.S. expansion program in 1982-83
The patented fibre is five times as strong as steel and 10 times as strong as aluminum on a pound for pound basis yet its density is 43 lower than fiberglass
The high temperature stability strength and insulation characteristics
of Kevlar have made it the preferred product in many applications
where asbestos replacement is sought Among them are transmission
clutch facings brake linings gaskets tires conveyor belting and high temperature resistant apparel
Two years ago after an extensive development program and with the help of Du Pont Canada Canadian Metallic launched a premium line of Super brake linings which proved to last up to four time the life of conventional asbestos linings Some trucks have clocked more than 200,000 miles on Novas with a wear of less than 0.10 inch per 100,000 miles says Anderson
Now Canadian Metallic has launched its Nova II asbestos brake linings
The Nova II incorporates a lesser amount of Kevlar and is designed particularly for truck fleets whose owners are concerned with environmental problems related to asbestos and who want linings that will last longer
says Beri
The new linings were subjected to demanding field tests before market introduction We placed test sets on underground scoop trams used by a Sudbury mining company where the brakes would be innundated with water and sticky mud So far they have more than six months of continuous service with no problems says Anderson
TXX 16
Overall Canadian for the Nova II
Metallic is confident of excellent customer experience line Field testing shows for instance that brake
drums are left unscored after up to 100,000 miles of use
Du Pont Canada Inc. Att 2 pp 2 3 4
55
And that's precisely why an Arrow Bulk hauling rig was selected in 1983 as test application for new SuperNova asbestos brake blocks Developed by
Canadian Metallic Brake Ltd. for use on
trucks and heavy road equipment these asbestos brake blocks are com pounded of special resistant resins
and reinforced with Du Pont Kevlar
aramid fiber along with other high
ity friction materials
A Better Brake Block
The SuperNova is a premium brake
block that conservatively offers at least eight times the performance life of conventional asbestos brake blocks boasts Michael Beri president of Canadian Metallic It also delivers twice the brake life of metallic blocks and doesn't score the brake drums the way metallics generally do In all respects it's the enduring performance brake block we set out to formulate five years ago
It was 1980 that Beri began focusing on Kevlar an aramid fiber marie only by Du Pont as the reinforcing core of a performance lasting brake block The high track record of Kevlar demonstrated strength
low weight abrasion resistance and outstanding thermal properties in applica-
tions ranging from aircraft and rockets to boat hulls and protective body armorsuggested a promising candidate for friction products subjected to intense heat and pressure Following two years of try-
ing and testing formulations Canadian Metallic went commercial with its
SuperNova brake blocks in October 1982. An early priority was to demonstrate the brake superiority of the new blocks through comparative data
generated in the field * Hayes Inc. a supplier of truck trailer axle components was signed on as
major Canadian distributor for the new asbestos brake blocks Doug Angus
'
of Hayes supplied SuperNova
blocks to a number of trucking opera-
tions for field tests
In April 1983. SuperNova brake
blocks were mounted on the two drive axles of one of Arrow Bulk's Kenworth tractors and on the three axles of a
Knight dump trailer New Kelsey
brake drums also were installed at the start of the trial Four times each day this rig made the journey to the Ashcroft siding and back After eight weeks of serv
ice reports Jones a visual inspection re-
vealed that the blocks still had 75 percent useful lining life remaining At this point
he adds three or four replacement sets
of asbestos blocks would have been in-
stalled due to block disintegration
Blocks Drums Fine At 12 Weeks
Hubs and drum assemblies were
pulled at 12 weeks No disintegration of the SuperNova blocks close to 50 percent of lining life remaining drum sur-
faces smooth with no scoring With metallics says Jones we'd have
been replacing both blocks and drums by this time The SuperNova blocks were
fine so we put them back on the wheels . to see how long they really would last
In January 1984 nine months and 65,000 miles after the start of the trial the center axle wheels on the trailer were realigned No new blocks or drums were
required In February with 72,000 miles logged all four truck wheels were realigned Brake blocks and drums still were compatible and serviceable It wasn't until April 1984 after 90,000 miles of
hauling that Arrow Bulk finally re-
placed the brake blocks and drums on the
rear axles of the trailer
In addition to extended performance life brakes reinforced with Kevlar 1 recover well with controlled fade 2 help
minimize cracking around rivet holes
3 won't glaze or smear because Kevlar doesn't melt as glass fiber does and 4
won't rust since Kevlar is nonmetallic
Du Pont Canada Inc. Att 1 pp 2-4
56
Canparts Automotive International Ltd. a Cambridge
Ontario manufacturer of automotive disc brake pads has
developed a line of replacement products which wear like semi-
surfaces metallics but are not detrimental to rotor The brake
are reinforced with Du Pont's Kevlar aramid fiber segments
Integrally molded pads for imported cars have passed a year of extensive field trials Based on their experience with the molded pads the company is now expanding to drilled disc pad
segments for domestic cars
-
<<- a ~*~
Improved performance has made the reinforced
product successful says Canparts president Bill Bartels
We've sold more than 300 000 pads to North American rebuilders
and distributors
Based on our lab test results wear rate for the projected life of the pads made with Kevlar is only 10 - 12 percent the
same as metallics compared with an 18 - 25 percent wear
rate for asbestos products adds Bartels
Canparts 681 material has several advantages over metallics as well Unlike metallics the new pad
linings are not detrimental to rotor surfaces and do not rust
under rivet heads The pads greatly reduce transmission of heat to brake fluid and they are not prone to brake squeal or dusting
Kevlar was chosen for its unique combination of high tensile strength high resistance to wear abrasiveness and excellent high temperature performance It can also be used with existing manufacturing equipment
One of the most attractive advantages of Kevlar is its processibility says Arnold Salt principal with Canparts and a formulator with 40 years experience We have had no problems using the aramid fiber with our existing equipment
Du Pont Canada Inc. Att 3 pp 1-2
TV 10
57
Another Canadian industry has discovered the advantages of and a new use for the world's strongest synthetic fibre
Du Pont's Kevlar aramid fibre is now being incorporated
in industrial brake blocks used to control the tensioning of yarn twisting machines at one of Canada's largest synthetic rope and twine manufacturing companies Twine a division of Niagara Structural Steel St. Catharines Ltd. a Tecsyn International Company
The results are reduced costs increased productivity and
fewer plant environmental concerns
Du Pont Canada Inc. Att 4 p 1
20
2 Commercial Availability
58
Today Arrow Bulk Carriers are using our Super brake blocks on most of their fleet notes Bob Anderson national sales manager for Canadian Metallic We're now offering worldwide a complete line of brake blocks using Kevlar
aramid
Du Pont Canada Inc. Att 1 p 3
59
The outstanding success of Canadian Metallic Brake Limited of Toronto
in replacing asbestos with Du Pont's Kevlar aramid fibre as the primary reinforcement for brake linings has led to a sales volume increase of roughly 70 in just one year according to sales vice president
Robert Anderson
Already established as a quality service supplier to the heavy parts distribution industry Canadian Metallic's tough brake linings also being specified by several original equipment
makers including Trailmobile Fruehauf and axle manufacturers Hayes Dana & Ingersoll Machine Tool Company
Buyers of Super and Nova II linings are our best salesmen
says Anderson One customer tells a user who tries them who tells another user who tries them and on Our Kevlar based products have had outstanding acceptance We are now operating three shifts a day six days a week and nearly 60 of our gross business comes from products incorporating Du Pont aramid fibre
IV
The company's complete line of friction products will eventually
be free of all asbestos reinforcement with Kevlar being
substituted throughout Beri confirms We now have the technology
to blend Kevlar with appropriate resins according to use application regardless of friction classification he says
Du Pont Canada Inc. Att 2 pp 1 3
60
Canparts supplies an extensive line of replacement parts to customers in more than 40 countries It has been searching for an organic replacement for asbestos in friction material for the
automotive aftermarket since the company was formed in 1980 and
finally found it with Kevlar
Canparts introduced the new domestic brake pads at the
1982 Automotive Parts Rebuilders Association show in Atlanta
in October The complete line will be ready for the U.S. aftermarket in January 1983 and will be priced competitively
with metallics
Du Pont Canada Inc. Att 3 pp 3-4
IV
3 Cost
61
The SuperNovias
a premium brake block that costs twice
as mucha traditional asbestos block
says Angus We wanted to demonstrate that its extraordinary brake advan-
tages make it a sound value buy
They pay significant dividends to truck fleets through decreased brake service and parts replacement Kevlar
aramid brings a lot of plus features to
brake blocks
Du Pont Canada Inc. Att 1 pp 2 3
62
We found and our customers now confirm that the Kevlar aramid
fibre's exceptional flexibility toughness and abrasiveness make our linings highly effective says Beri
Since for many applications as little as 20th of the weight of Kevlar compared with asbestos may be needed the end price to consumers of asbestos friction products can
be kept fully cost comparative
Du Pont Canada Inc. Att 2 pp 1 2
63
A traditional asbestos pad could contain 40 to 60 percent asbestos he added but we use considerably less Kevlar plus fillers and come up with a product competitive to metallic
disc pads
Du Pont Canada Inc. Att 3 p 3
IV 23
4 Experience See comments 54-57 on Applications and Performance
IV 24
E. Substitutes in General - Availability Performance Health Effects Safety
TV 25
64
This report identifies appliaplications cations for which asbestos asbestos has
is ised in motor vehicle systems and components and
discuses the performance and customer acceptance criteria that
the the selection of asbestos for those applications Alterc3-
materials materials materials for those applications are examined in relation to
selection selection
criteria vehicle design
substitution and the effect on
changes vehicle
necessary to accommodate
performance including
with safety and other governmental regulations
I.
General Discussion
A.
Characteristics of Asbestos and the Difficulties
of Finding Acceptable Substitutes
The advantageous characteristics asbestos imparts to products used in the motor vehicle industry include
-
fire resistance
-
thermal and chemical stability
-
structural and flex strength
-
moisture resistance
-
dielectric strength
-
low cost
-
good friction and wear properties
-
permeability
There are few alternate materials which have the
total combination of these desirable characteristics
Developing and approving acceptable substitute materials is a task requiring extensive research and testing
programs materials
The must
many different potential substitute
be evaluated over the wide range of
environmental conditions under which a motor vehicle
operates In addition the ripple effect of a substi-
tution must be investigated to be sure the performance
of other vehicle components is not adversely affected
This is further complicated by the variety of materials
used on our many different vehicles and the many
customized applications
IV
1 Applications and Performance
50
We wish to call EPA's attention to the availability of and to the
possible use of low cost low modulus industrial grade carbon fibers as a
suitable substitute for asbestos in automobile and truck brakes
Carbon fibers have been evaluated and are being used in brake
applications for aerospace military and commercial aircraft racing cars
road vehicle and industrial and now to some extent in automotive uses in
proprietary formulations Here carbon fiber properties of high strength wear resistance good frictional properties good binding qualities high conductance high thermal stability oxidation resistance and low weight them most attractive carbon fiber composites are considered the
material brakes of choice for high performance military and commercial aircrafts
good
heat
make
Ashland's contacts in brake manufacture also indicate that carbon fibers
can and are competitive to an extent with asbestos performance and that neither retooling or special processing techniques would necessarily be
required to permit substitution of carbon fibers for asbestos
Ashland Petroleum Company pp 1 2
51
Carbon fibers are materials currently used in a number of industrial
applications calling for high strength and low its use today include graphite tennis rackets
weight Examples of golf clubs and aircraft
parts However growth of this market has been limited by the cost
of producing high performance fibers used in these applications Ashland's carbon fibers are produced at considerably lower cost
and are intended for general applications where specifications are
less severe This production breakthrough should help the market
expand
Anticipated new markets for general purpose fibers include fillers for polymers engineering plastics brake linings high temperature thermal and sound insulation other temperature applications replacing
asbestos automotive parts construction materials carbon
fiber composites and a variety of military applications
Ashland Petroleum Company Att 1 pp 1-2
2 Commercial Availability
52
Ashland presently has the capability of producing 30 year of general
purpose carbon fiber GPCF and will expand production to 100 year in the
fall of 1985
Ashland Petroleum Company p 1
3 Cost
53
Ashland's carbon fibers are marketed under the tradename
lengths CARBOFLEX range in price from 10 to 12
nonwoven mat chopped 1/8 to 1/2
per pound and come in the forms of , and ground or milled 100 to 400
microns average length
In the past the unavailability of low cost fibers
to their exploitation in automotive brake applications
formulations we understand that the amount of fiber is
has been a deterrent
although in brake pad
rather low in
composition Because we manufacture a proprietary raw material from which we produce our fiber and which is sufficient to produce up to 50 million pounds per year of fiber the potential exists for an even less expensive fiber if produced in much large volumes Ashland is dedicated to a continuing effort
of further improvements in cost performance so as to enhance the effectiveness
of carbon fiber
Ashland Petroleum Company p 1
D. Kevlar Aramid
1 Applications and Performance
54
Kevlar was first introduced by E. I. du Pont de Nemours & Company in 1972 with an initial investment commitment of more than 500 million U.S. followed by a 200 million U.S. expansion program in 1982-83 The patented fibre is five times as strong as steel and 10 times as strong as aluminum on a pound for pound basis yet its density is 43 lower than fiberglass
The high temperature stability strength and insulation characteristics
of Kevlar have made it the preferred product in many applications
where asbestos replacement is sought Among them are transmission
clutch facings brake linings gaskets tires conveyor belting and high temperature resistant apparel
Two years ago after an extensive development program and with the
help of Du Pont Canada Canadian Metallic launched a premium line of Super brake linings which proved to last up to four time the life of conventional asbestos linings Some trucks have clocked more than 200,000 miles on Novas with a wear of less than 0.10 inch per
100,000 miles says Anderson
Now Canadian Metallic has launched its Nova II asbestos brake
linings
The Nova II incorporates a lesser amount of Kevlar and is designed
particularly for truck fleets whose owners are concerned with environmental
problems related to asbestos and who want linings that will last longer
says Beri
The new linings were subjected to demanding field tests before market introduction We placed test sets on underground scoop trams used by a Sudbury mining company where the brakes would be innundated with water and sticky mud So far they have more than six months of continuous service with no problems says Anderson
Overall Canadian Metallic is confident of excellent customer experience for the Nova II line Field testing shows for instance that brake drums are left unscored after up to 100,000 miles of use
Du Pont Canada Inc. Att 2 pp 2 3 4
55
And that's precisely why an Arrow Bulk hauling rig was selected in 1983 as a test application for new SuperNova asbestos brake blocks Developed by Canadian Metallic Brake Ltd. for use on trucks and heavy road equipment these asbestos brake blocks are com pounded of special resistant resins and reinforced with Du Pont Kevlar aramid fiber along with other quality friction materials
A Better Brake Block
The Super is a premium brake block that conservatively offers at least eight times the performance life of con-
ventional asbestos brake blocks boasts
Michael Beri president of Canadian Me-
tallic It also delivers twice the brake life of metallic blocks and doesn't score the brake drums the way metallics
generally do all respects it's the enduring performance brake block we
"
set out to formulate five years ago
It was in 1980 that Beri began focusing on Kevlar an aramid fiber marie only by Du Pont as the reinforcing core of a performance lasting brake block The high track record of Kevlar demonstrated strength low weight abrasion resistance and outstanding thermal properties in applications ranging from aircraft and rockets to boat hulls and protective body armorsuggested a promising candidate for friction products subjected to intense heat
and pressure Following two yearosf try-
ing and testing formulations Canadian Metallic went commercial with its
SuperNova brake blocks in October 1982. An early priority was to demonstrate the brake superiority of the new blocks through comparative data generated in the field
Hayes Inc. a supplier of truck trailer axle components was signed on as a major Canadian distributor for the new
asbestos brake blocks Doug Angus
of Hayes supplied SuperNova
blocks to a number of trucking opera-
tions for field tests
In April 1983 SuperNova brake
blocks were mounted on the two drive axles of one of Arrow Bulk's Kenworth tractors and on the three axles of a
Knight dump trailer New Kelsey
brake drums also were installed at the start of the trial Four times each day this rig made the journey to the Ashcroft sid ing and back After eight weeks of serv ice reports Jones a visual inspection revealed that the blocks still had 75 percent useful lining life remaining At this point he adds three or four replacement sets of asbestos blocks would have been in-
stalled due to block disintegration
Blocks Drums Fine At 12 Weeks
Hubs and drum assemblies were
pulled at 12 weeks No disintegration of the SuperNova blocks close to 50 percent of lining life remaining drum sur-
faces smooth with no scoring With
metallics says Jones we'd have
been replacing both blocks and drums by this time The SuperNova blocks were
fine so we put them back on the wheels to see how long they really would last
In January 1984. nine months and 65,000 miles after the start of the trial the center axle wheels on the trailer were realigned No new blocks or drums were required In February with 72.000 miles logged all four truck wheels were realigned Brake blocks and drums still were
compatible and serviceable It wasn't
until April 1984 after 90,000 miles of hauling that Arrow Bulk finally replaced the brake blocks and drums on the
rear axles of the trailer
In addition to extended performance
life brakes reinforced with Kevlar 1 recover well with controlled fade 2 help minimize cracking around rivet holes 3 won't glaze or smear because Kevlar doesn't melt as glass fiber does and +
won since Kevlar is nonmetallic
Du Pont Canada Inc. Att 1 pp 2-4
56
Canparts Automotive International Ltd. a Cambridge
Ontario manufacturer of automotive disc brake pads has
developed a line of replacement products which wear like semi-
metallics but are not detrimental to rotor surfaces The brake
segments are reinforced with Du Pont's Kevlar aramid fiber
Integrally molded pads for imported cars have passed a year of extensive field trials Based on their experience with the molded pads the company is now expanding to drilled disc pad
segments for domestic cars
_
_<- a-
Improved performance has made the reinforced
product successful says Canparts president Bill Bartels
We've sold more than 300 000 pads to North American rebuilders
and distributors
Based on our lab test results wear rate for the projected life of the pads made with Kevlar is only 10 - 12 percent the same as metallics compared with an 18 - 25 percent wear
rate for asbestos products adds Bartels
Canparts 681 material has several advantages over metallics as well Unlike metallics the new pad linings are not detrimental to rotor surfaces and do not rust under rivet heads The pads greatly reduce transmission of heat to brake fluid and they are not prone to brake squeal or dusting
Kevlar was chosen for its unique combination of high tensile strength high resistance to wear abrasiveness and excellent high temperature performance It can also be used with existing manufacturing equipment
One of the most attractive advantages of Kevlar is its processibility says Arnold Salt principal with Canparts and a formulator with 40 years experience We have had no problems using the aramid fiber with our existing equipment
Du Pont Canada Inc. Att 3 pp 1-2
57.
Another Canadian industry has discovered the advantages of and a new use for the world's strongest synthetic fibre
Du Pont's Kevlar aramid fibre is now being incorporated in industrial brake blocks used to control the tensioning of yarn twisting machines at one of Canada's largest synthetic rope and twine manufacturing companies Twine a division of Niagara Structural Steel St. Catharines Ltd. a Tecsyn International Company
The results are reduced costs increased productivity and fewer plant environmental concerns
Du Pont Canada Inc. Att 4 p 1
2 Commercial Availability
58
Today Arrow Bulk Carriers are using our SuperNova brake blocks on most of their fleet notes Bob Anderson national sales manager for Canadian Metallic We're now offering worldwide a complete line of brake blocks using Kevlar aramid
Du Pont Canada Inc. Att 1 p 3
59
The outstanding success of Canadian Metallic Brake Limited of Toronto
in replacing asbestos with Du Pont's Kevlar aramid fibre as the primary reinforcement for brake linings has led to a sales volume increase c roughly 70 in just one year according to sales vice president
Robert Anderson
Already established as a quality service supplier to the heavy parts distribution industry Canadian Metallic's tough brake linings also being specified by several original equipment makers including Trailmobile Fruehauf and axle manufacturers Hayes Dana & Ingersoll Machine Tool Company
Buyers of Super and Nova II linings are our best salesmen
says Anderson One customer tells a user who tries them who
tells another user who tries them and on Our Kevlar based products have had outstanding acceptance We are now operating three
shifts a day six days a week and nearly 60 of our gross business comes from products incorporating Du Pont aramid fibre
The company's complete line of friction products will eventually
be free of all asbestos reinforcement with Kevlar being
substituted throughout Beri confirms We now have the technology to blend Kevlar with appropriate resins according to use application regardless of friction classification he says
Du Pont Canada Inc. Att 2 pp 1 3
60
Canparts supplies an extensive line of replacement parts to
customers in more than 40 countries
It has been searching for
an organic replacement for asbestos in friction material for the
automotive aftermarket since the company was formed in 1980 and
finally found it with Kevlar
Canparts introduced the new domestic brake pads at the
1982 Automotive Parts Rebuilders Association show in Atlanta
in October The complete line will be ready for the U.S.
aftermarket in January 1983 and will be priced competitively
with metallics
Du Pont Canada Inc. Att 3 pp 3-4
3 Cost
61
The SuperNovias
a premium brake block that costs twice
as much as a traditional asbestos block
says Angus We wanted to demonstrate that its extraordinary brake advantages make it a sound value buy
They pay significant dividends to truck fleets through decreased brake service and parts replacement Kevlar aramid brings a lot of plus features to
brake blocks
Du Pont Canada Inc. Att 1 pp 2 3
62
We found and our customers now confirm that the Kevlar aramid
fibre's exceptional flexibility toughness and abrasiveness make .
our linings highly effective says Beri
Since for many applications as little as 20th
of the weight of Kevlar compared with asbestos may be needed the end price to consumers of asbestos friction products can be kept fully cost comparative
Du Pont Canada Inc. Att 2 pp 1 2
63
A traditional asbestos pad could contain 40 to 60 percent
asbestos he added but we use considerably less Kevlar plus
fillers and come up with a product competitive to metallic
disc pads
Du Pont Canada Inc. Att 3 p 3
4 Experience
See comments 54-57 on Applications and ) Performance
E. Substitutes in General - Availability Performance Health Effects Safety
This report identifies applications for which asbestos nas
been or is ised in motor vehicle systems and components and
discusses the performance and customer acceptance criteria that
led to the selection of asbestos for those applications
Alterna
tive materials for those applications are examined in relation to
selection criteria vehicle design changes necessary to accomodate
the substitution and the effect on vehicle performance including
compliance with safety and other governmental regulations
I.
General Discussion
A.
Characteristics of Asbestos and the Difficulties
of Finding Acceptable Substitutes
The advantageous characteristics asbestos imparts to products used in the motor vehicle industry include
-
fire resistance
-
thermal and chemical stability
-
structural and flex strength
-
moisture resistance
-
dielectric strength
1
low cost
-
good friction and wear properties
-
permeability
There are few alternate materials which have the
total combination of these desirable characteristics
Developing and approving acceptable substitute materials
is a task requiring extensive research and testing
programs materials
The
must
many different potential substitute
be evaluated over the wide range of
environmental conditions under which a motor vehicle
operates In addition the ripple effect of a substitution must be investigated to be sure the performance of other vehicle components is not adversely affected This is further complicated by the variety of materials
used on our many different vehicles the many
customized applications
Need
for Systems Systems
Evaluation Evaluation of
Potential Potential Potential Potential Potential
Sub
Sub Sub ur
' ce
'
'
vb
eevee
vi
For the majority of current applications other than
brakes many substitutes for asbestos may be available
This is a generalization and is conditioned by productand application constraints In most cases the containing material was part of a larger
system e.g. asbestos head gaskets are a portion of larger system the engine Thus the question of suitable substitutes must be approached on a total
the
system basis A direct substitution of some other fiber for asbestos is often not feasible without modification
of a larger system While substitutes exist there is still a substantial research effort required before substitute materials can be released for full production Further substitution must be approached on a product function
function basis In this way the asbestos substitute
can be fully evaluated for performance in the vehicle including related concerns and consumer acceptability Health safety and environmental factors related to substitute usage during vehicle manufacture must also be fully evaluated MVMA cautions against inadequate consideration of all factors involved
with a substitute material A substitute which results
harmful in unacceptable vehicle performance or safety or is
more
than asbestos to workers is an unaccept-
able substitute
Asbestos offers a unique combination of properties in a
single material Not all of the properties can be matched
with a single substitute therefore total system redesign
may be
required
to
achieve
the
desired
considered
considered
result
Ripple
effects
effects
effects
must
must
alals so o
be
considered
1.9
if
compnets componets new bart has a different size or shape rust other
the the the
the
new
componecompnonentsts
new
components components
or subassemblies be redesigned
part Once a potential system performance tested and if the
to accommodate the ne new w
is designed it must be
substitute meets the
performance criteria mass production methods must be devised All this necessitates a considerable design
engineering and testing effort
C.
Status of Substitute Availability
- Brakes -
One of the primary applications for asbestos in our industry is brake lining materials The suitability
of brake linings to the great variety of cars multipurpose passenger vehicles light trucks vans medium and heavy duty trucks tractors and buses requires extensive development Brake systems are
required to meet a variety of Federal and State
regulatory requirements including FMVSS 121 Air
Brakes and 105 Hydraulic Brakes BMCS regula-
tions and various state laws
Many vehicle manufacturers are dependent upon brake
and lining suppliers to develop initially screen new materials
produce and
The rate of
development of these new materials is not only limited to available expertise but to the
laboratory and vehicle equipment as well as
manpower at vendors Until these materials are
manufacturers developed the vehicle
Substitution will lead
ol
in os re c
brake
can do pads
little Drum
pasenger brake linings for passenger
can probably be asbestos
pasenger cars
free free free in
and the
light tr c
next several
years
truck
Heavy
truck drim crake crake crake crake systems however
will take longer
In addition to the obvious need to stop the vehicle safely each supplier and manufacturer has requirements which he deems to be important and must be met Among these are
Requirements
Acceptable Lining Life - Lining
materials must provide the customer with acceptable lining life in the great variety of
uses to which vehicles are put
Leading Lining Material
Semi
Acceptable Drum and Rotor Life -
Brake materials must be compatible with drums or rotors they contact
and not cause excessive wear
grooving or cracking
Asbestos
- Structural Strength - Linings must
have sufficient strength to prevent
cracking chipping flaking and
delamination shearing in their
various strenuous uses
The
capability to tolerate flexure of its supporting elements is an essential requirement
Green or Preburnish Performance -
Linings must provide reasonable performance and stability when new
Asbestos
Semi
Water Recovery - Lining materials must be able to provide adequate performance when exposed to water and to recover the initial performance and stability within a short
time
Fade Resistance - Linings must provide adequate performance and stability when subjected to high temperatures and then cooled They should provide approximately their original ambient performance after being exposed to temperatures as high as 1200
Parking Capability - Linings must provide sufficient static retarding force to support grade holding demanded of the parking brake
system
8
Dimensional Stability - Lining
material must not swell at high
temperatures or when exposed to
moisture or undergo length or
width dimensional changes that
could result in structural cracks
Performance Consistency - Lining material performance must be relatively consistent over a wide range of temperatures and operational
conditions
10
Low Temperature - Materials must
provide acceptable performance and
durability
and on the tion
at low ambient temperatures first daily brake applica-
11.
Lining Attachment to its support
element >> Current methods may not be
suitable for new materials This
interface could require additional development and testing
Semi
Either with slight edge to
asbestos
No problem
Either Asbestos Asbestos
In addition the customer demands a number of th 10 from brakes and linings including
Requirements
Absence of Noise - Noisy brakes and linings generate driver and
community complaints and therefore
cannot be tolerated
Leading Lining Material
Either
Modulation and Control - Drivers
demand
brakes and
linings which
provide performance and control with reasonable pedal efforts under all
conditions of load and traction
Asbestos
Lining and Rotor Life - Customers
demand long service life in a variety
of vocational uses environmental
conditions duty cycles and geographical
locations
Lining
To meet all these real needs and requirements is an extemely difficult laborious task involving many development hours Materials must be subjected to great variety of test conditions The problem is complicated further by the variety of brakes - both in size and type - that this industry uses in many different vehicles and customized applications
Government regulations have further increased the need on heavy trucks to customize brakes and brake systems
Prior to FMVSS 121 manufacturers used one brake size and torque capacity for many axle capacities and applications That practice has been curtailed by FMVSS 121's dynamometer requirement and the possibility of reimposed stopping distances as part of this regulation FMVSS 105/75 subjects passenger car MPV and light truck brake systems to severe duty cycles and temperatures which result in very rigorous demands on the brake lining
materials
?
Lining material selection involves many engineering
consumer and regulatory considerations
GovernmentGovearnmentall
regulatory agencies
differing materials
such will
as OSHA must realize that many
be required to replace the .
great variety of asbestos linings manufacturers
currently use There appear to be a few acceptable
linings asbestos lining
brake pads and some
materials passenger
available today
car drum brake
for
disc
The processing of asbestos materials may require
different manufacturing equipment and techniques because
of clumping and chemistry changes mixer speeds have to
be varied and pressure changes made It will take time
to develop these techniques controls and the machines
to support industry volumes Some of the asbestos
disc pads used by vehicle manufacturers still incorpo-
rate an asbestos backing for reasons explained later in
the general discussion on brake friction materials
Brake components such as linings have high exposure in the safety compliance recall and product liability areas. Therefore vehicle manufacturers must be certain they are not correcting one problem and creating another It should be pointed out that this was exactly the case with FMVSS 121. The performance levels and effective date mandated by that standard generated the hasty development of components which were unacceptable to the consumer and which introduced new performance problems If justification is found for a change of this magnitude sufficient time must be provided to assure that existing linings will not be replaced with others the consumer will not accept
Linings are a key factor in any brake design and asbestos is a key factor in many lining materials If asbestos is eliminated from brake linings manufacturers must retest and requalify every vehicle brake application currently using asbestos
Summary and Conclusions
ap lications For the majority of the asbestos applications
vehicles acceptable substitute materials
applications applications
materialsmaterials are
in motor
in varying
stages of development It is possible that many substi-
tutions i.e. fillers and sealers can be accomplished
in the next few years
However there are certain
critical uses of asbestos for which finding acceptable
substitutes will take considerably longer These are
heavy truck brake linings and engine preformed gaskets
These special applications will require system redesign
to accommodate the properties of asbestos materials
II B.
Specific Vehicle Applications
Friction Products - Brakes Passenger Cars & Trucks
Discussion
Friction materials for automotive brakes are
complex composites containing three general types of ingredient materials reinforcing fibers modifiers that adjust or maintain friction level
wear rate and noise properties and organic resin binders Historically the foundation or major
constituent of automotive friction materials has
been chrysotile asbestos fiber so chosen because
of thermal stability friction level reinforcing
properties availability and relatively low cost
metallic asbestos friction materials were
originally developed to meet higher capacity and
temperature requirements for heavy and front
'
wheel disc brakes
sucesfuly sucesfuly sucesfuly used metallic lining are
Disc
now
oake oake oake oake
asmeaer
U
aa)
eine ue
ad
1
u
1 t
t
sucesfuly sucesfuly successfully
successfully
used used used
for for
for
a
Pasenger wide range of venicles
Passenger Passenger Passenger Passenger carscarscars cars
lign lign lign lign 6k
cars trucks and multi
pasengr wil vehicles vehicles requirerequire completely asbestos
pasenger passenger
vehicles
vehicles
will will require require require
with with with further further further further further further
development of asbestos drum brake shoes a
drum much more difficult set of design materials and
manufacturing problems that existed for disc pads
Substitution is especially difficult for dual servo
type drum brake systems which are predominant on
rear wheel drive vehicles because these systems
require highly consistant friction coefficient for
smooth application
Most hydraulic disc brake shoe and lining assemblies contain an asbestos backing material The primary
reasons are to control heat transfer and to aid in
attachment of the lining to the metal shoe Eliminating the asbestos backing material requires considerable development in order to maintain attachment strength and control heat transfer to
the brake fluid
Control of the various materials in lining is critical Wear problems are currently being encountered due to impurities found in a key ingredient Control of materials and processes continues to be a challenge
Considerable resources are currently to correct field problems with noise
temperature wear
being expended
and low
Heavy Trucks - Air Brake Liners and Blocks
asbestos blocks have been found to crack and
delaminate This condition causes user concern In addition since asbestos materials do not have the flexure strength of asbestos materials
shoe rigidity and dimensional accuracy become new challenges to be resolved from a manufacturing
Substi te te Substi Substi ere
Substi re
Materials
Major types of asbestos brake formulations are
1
Organics using combinations of other fibrous
materials such as fiberglass and mixed
compounds of calcium silicate aramids rein-
forcing fibers as substitutes for asbestos in
formulations that use an organic resin binder
2
metallics - consisting of steel wool
sponge iron graphite ceramic powder and
other substances in a phenolic resin binder
3
Sintered and ceramic powders as well as
inorganic friction modifiers fused together
under extremely high temperature and pressure
Organic materials have the least cost the easiest lining attachment and the greatest structural strength However their wear rate and fade resistance are the poorest Lining swell can also be a problem Organic materials are used primarily for drum brake systems
metallic linings have better wear and fade characteristics than organic materials However they cost more and have less static retarding force and generally require an asbestos backing material in order to insure adequate attachment shear strength on disc pads Lining swell generally is not a concern
Sintered metal materials are very costly extremely difficult to attach to a shoe and have the poorest flexure tolerance However they have the best wear rate and fade resistance at high temperatures Static retarding and burnish performance are also problems with these materials
Motor Vehicle Manufacturers Association Att 3 pp 1-12
IV
65
This industry is regulated its products being one of the critical materials in hydraulic and air brake systems Brake Linings used in new vehicle brake systems must undergo lengthy qualification and certification tests by the producer and customer before release Formula or significant processing
changes on released products cannot be put in effect without requalifica-
tion and recertification There is also considerable lead time involved
when formula or processing change is planned Change is not only timeconsuming but it is costly Development of a new formula along with the required testing for compliance with either DOT Standard 105 Hydraulic Brake Systems or 121 Air Brake Systems and moving the product into production can cost in excess of 250,000 and product or process modifica-
tion costs may also approach this figure
Products using substitute materials have a material cost two to three times the cost of the asbestos based product being replaced The cost increase is not limited to material costs Most substitute materials require sub-
stantial capital equipment investment as well as additional labor cost While there has been progress in the automotive highway market the industrial highway market is almost an entirely different market One cannot substitute certain fibers in friction products used in underground
mining equipment for fear of a induced explosion The friction material used in overhead cranes handling hot metal or heavy loads may not
accept a substitute material without adding another hazard
highway friction products have requirements above and beyond
usage and must be tailored to the product line
These off-
normal highway
Motor Vehicle Manufacturers Association Att 4 pp 1-2
TIZ
21
66
Further the availability of economically and technologically
feasible substitutes for asbestos is an issue in which the friction
materials manufacturers are deeply involved The identification of such substitutes is a major ongoing program with the manufacturers and is not a completed program at this point in time Total endorsement of Section - of the petition is not appropriate since friction materials manufacturers produce disc pads and drum segments for passenger cars and light to medium trucks as well as brake blocks
for heavy trucks The claims made in Section B relate to brake blocks
and cannot be endorsed for all product lines Further actual experience to date has proven that substantial processing modifications and new equipment are required for the asbestos substitute materiais The advantages of metallic brake linings cited in Section - are not necessarily supported by test results generated by friction materials manufacturers While certain of these claimed advantages may be true
where the application generates high braking temperatures they are not
necessarily true for the average consumer
Sufficient data is not at available this time on the substitute materi is
to state that they do not pose a hazard in the workplace environment or to the general public We wish to cite a recent study by the Canadian Royal Commission on Matters of Health and Safety Arising from Use of Asbestos in Ontario and an earlier paper on asbestos Related Malig-
nant Mesothelioma
These comments follow
... the production of substitute fibres in the future should increase the exposure of workers to Long thin durable fibres of dimensions similar to those we have found hazardous for
asbestos we cannot be sure that serious health consequences
would not result To the face of the existing evidence we
believe it would be risky to allow the exposure of workers to
respirable fibres longer than 5 microns with small diameters
of any material if those fibres are likely to be very durable
in
the
material
lungs
It has been generally accepted now that the fibre which is
carcinogenic is a durable long and thin fibre the diameter of less than 1.5 micron and length of more than 8 micron
appearing critical A number of fibrous materials other than
asbestos can appear in this size and shape and indeed have been established as couse of mesothelioma in animals such as
glass fibres aluminum oxide tremolite attapulgite dawsonite
silicon carbide and potassium titanate
Report Bae
of the Royal Commission of Matters of Health and Safety Arising
from the Use of Asbestos in Ontario 1984 Ontario Ministry of the
Attorney General Toronto
asbestos Related Malignant Mesothelioma - A Review of the
and Medical Literature Premysl V. Pelnar MD citing a paper Layard Tegeris Miller May and Kent that appeared in the J. Cancer Inst March 1977
Scientific
by Stanton
Natl
Friction Materials Standards Institute Inc. Att 1 pp 2-4
67
Effective substitutes may not be available for certain
applications of asbestos in brakes and substitutes for other
applications are not available in sufficient quantities because of limited production capacity
III POSSIBLE SUBSTITUTE FOR ASBESTOS
Possible substitutes for asbestos are represented by the
following materials alamid fiber glass fiber and various inorganic fibers and steel fiber However the safety of these fibers for human health is not yet proved When asbestos is substituted the following conditions will exist
a Disc brake pad From a viewpoint of securing a long brake life the metallic pads are adopted to certain types of vehicles especially passenger vehicles However as EPA pointed out the metallic pad is characterized as having a coefficient of friction which varies with temperature Therefore it is
not suitable for all types of vehicles
Further the asbestos contained friction
materials are used as a heat barrier However such materials cannot become a real asbestos friction material unless the
heat barrier is asbestos Another type
of disc brake pad contains the parking brake built This rod is provided not only with the capability required for normal service brake but also with that for the parking
brake In other words for this rod the
coefficient value of friction fluctuating in regard to the temperature change is low for this reason very few disc brakes adopt this type of metallic rod
b Lining for drum No substitute is available in Japan at this
moment
c Substitute for asbestos now under development 1 Disc brake pad Besides the above metallic pad the
friction material applying different
asbestos fiber is now under development However it is expected that
such material will be applied to various
kinds of vehicles after the mid 1990's As
as result it is expected that price
increases will follow
2 Lining for drum For this item asbestos brake using different fibers is now under development but
wide scale commercial use of asbestos
brake pads in vehicles is not expected until
on or after the mid 1990's because of the
unavoidable rise in prices for these pads
until then In any event in order to use
asbestos substitutes in various types of
equipment additional equipment or renewal of equipment will be required Taking into consideration the availability of substitute
fibers it is expected that we will encounter
difficulties if vehicles decide to adopt the
substitute materials It is recommended
that the action to prohibit the use of asbestos presently used as a major brake component and the substitution use of a
asbestos brake friction material should
be phased in smoothly over time granting sufficient lead time at each stage
Japan Automobile Manufacturers Association Att 1 pp 1 3-5
68
Even though these many uncertainties exist we
committed to the elimination of asbestos brake linings installed on
vehicles we manufacture
-
are
the
We have been working diligently for a number of years with the major brake lining
suppliers in the U.S. in an effort to find substitute materials for brake linings which do not contain asbestos Our experience to date shows that the development
of substitute materials is a very difficult and time consuming task It been
fraught with numerous problems many of which are recognized in the subject
notice
Because of the unresolved problems associated with many currently
available substitute materials we cannot project at this time when our suppliers
will be able to provide satisfactory asbestos brake linings for incorporation ~
on all of our vehicles
The development of satisfactory asbestos brake lining materials will take
time Over the years consumers in the U.S. have developed the expectation that
vehicle brake systems will provide safe reliable performance during many miles of
operation without maintenance and will be noise Many years were required
for vehicle manufacturers and suppliers to develop the expertise required to
provide asbestos lining compounds which meet these consumer demands and our
stringent safety and performance requirements under the multitude of widely
differing environmental and driving conditions experienced in the U.S.
These
lining materials also had to be engineered to provide balanced and consistent
stopping ability under all types of vehicle loading conditions under a very wide
variety of brake temperature conditions and with green and used linings
New asbestos brake lining compounds and formulations must be developed to
meet these same objectives
Because brake performance is important to vehicle
safety it must not be compromised by a premature switch to substitute materials
Some substitute materials have been developed and the use of asbestos material has
been substantially reduced but there is still much more work to be done before
it can be totally eliminated
manufactures has metallic
Currently all
front disc brake
but one vehicle
pads However
that Chrysler
we must stil
depend on asbestos as an underlayer medium on most applications to eliminate
stress cracks that appear during the bonding or riveting of the friction material
to the brake pad support plate No entirely satisfactory material has been found
to date which will provide the cushioning effect provided by the thin asbestos-
based underlayer material
Alternate materials for the underlayer are
evaluated in hopes of producing pads which are completely free of asbestos
being
We are working to employ asbestos substitute linings on new model vehicles as
part of the design and development process This process has not been without
problems however Recently we were forced to revert to containing linings on two introduced vehicles because of heavy disc brake scoring and inconsistent brake performance with asbestos substitutes
brake rotor These
difficulties appeared very late in the vehicles development program and may
ultimately cause a production delay However asbestos linings are planned
for several other applications on 1986 model year vehicles
Because of weight
distribution suspension characteristics and other factors each vehicle has
unique braking system requirements Consequently a particular lining formulation
that is acceptable on one vehicle may prove to be unacceptable on another
In view of the complexity involved with the development of a new brake system we
begin nearly three years before the first vehicle rolls off the assembly line
The and
first step in the process is the establishment of vehicle performance goals
objectives
These include all the requirements of Federal Motor Vehicle
Safety Standard 105 a minimum brake lining life of 50,000 miles under normal
driving conditions and noise operation for the life of the vehicle These
criterion along with other design parameters are conveyed to our friction material
Suppliers for candidate material selection
During this critical period of
development we are literally totally dependent on the recommendations they
provide Controlled laboratory tests narrow the field of candidates to the final
material to be used Vigorous tests during highway city traffic and mountain grade driving fine tune the system to ensure that it will meet our stringent safety and performance requirements and consumers demands for quiet effective and trouble performance
Chrysler Corporation pp 1-3
69 Our suppliers tell us that they are now in the process of phasing out the use of asbestos in the friction products that they supply to us We understand that by 1990 most if not all of these products will be asbestos as new car and truck lines are phased in containing systems are being phased out Despite some technical problems that remain we understand that good progress is being made
Ford Motor Company p 1
70 IH currently purchases from outside suppliers various components
containing asbestos
These include gaskets clutch facings
sealing materials and brake assemblies
Because
IH is
a
purchaser rather than a manufacturer of containing
products it is extremely concerned about the possible effect that
a ban on use of products in motor vehicles would have on its
product planning and engineering
If EPA prohibits use of containing components IH will need considerable lead time to identify test and adapt its
products to the
prohibition takes
use
of
asbestos
substitutes
the
effect
The attached letter dated March 8
1984 to one of IH's brake suppliers is submitted as Attachment A with these comments as an illustration of the magnitude of the
task facing vehicle manufacturers and their suppliers as well as the amount of lead time needed to incorporate the substitute
products into the vehicle after qualified substitutes are found
IH has already expended considerable
component
suppliers
to
identify
substitutes
However much more needs
effort to work with its
and
test
asbestos
to be done because safe
durable and competitively priced asbestos substitutes have
not been found for all containing components in all types
of brakes
This is all the more true because many of these
components are subject to Federal Motor Vehicle Safety Standards
which require a high level of performance and reliability
EXPERIENCE TO DATE WITH SUBSTITUTE MATERIALS
IH's experience with asbestos production hydraulic
disc brake linings dates back to 1976.
asbestos hydraulic
disc brake pads were first released for production in 1980
During the past three years IH has worked directly with its brake
. suppliers to find qualify and incorporate asbestos linings
into additional types of brake assemblies
So far however
regular production hydraulic service brakes air brakes and
driveline parking brakes still contain asbestos
Despite numerous articles in the trade press claiming exceptional
durability for asbestos brake linings IH has not always found
these claims
to
be true
While laboratory wear tests of
asbestos brake linings have shown good durability field tests
i.e. tests in actual use have revealed structural problems
such a delamination material breakdown and metal pickup in some
formulations and shortened drum lives in others
IH believes that reports of the availability of suitable
reliable and safe substitutes for containing brake
linings have been overly optimistic and may have misled customers
government agencies and the general public
IH is deeply
concerned that EPA might consider banning further use of all
containing components regardless of whether suitable
reliable
put into
and safe substitutes have been found
If such a ban is
place IH would recommend allowing exceptions to the ban
unless and until qualified substitute materials are found and can
be incorporated into products
Although the search for suitable substitutes in all applications has still not met with total success IH continues to be actively
involved in programs to test new lining formulations
As
an
example the previously mentioned March 8 1984 IH's program for qualifying asbestos materials
letter details for foundation
air brakes in tractor applications However this program covers
only one type of brake system in one application
requiremnts The basic types of truck brake systems include actuated can,
wedge and disc brakes and hydraulic drum and disc brakes Each
must
be
tested
in both
tractor
and
straight
system
applications
The wide range of braking requirements in trucks
of uses to which trucks may be
stems from the tremendous variety
from highway haul tractor operations to
put intra delivery
garbage and dump
trucks
and
service
applications such as oilfield logging and mining operations Each
type of brake system is employed because it does the job more
effectively in that particular application than any other type of
system
In the past eight years
IH has evaluated
asbestos lining formulations for disc brakes
one has been found to be acceptable for production
several
So
use
far
Our
dozen
only
first
series of cam drum brake tests started in 1983.
These tests were
terminated in early 1984 due to unacceptable results
We
are
a second series of tests with the best
currently
available
performing
materials on
braked
trucks and
tractors
This
testing program which began with truck tractors was expanded in
the fall of 1984 to testing of buses and medium Class 6 and
7 GVWR straight trucks
The test series involves the following
phases
1
Screening tests of lining materials by suppliers including
dynamometer certification
torque
capacity
structural
integrity and wear
2
Vehicle tests at the IH Proving Grounds including tests of
.
vehicle performance
grade holding
and
compatibility
compared to asbestos linings
3
Field tests of selected fleets of approximately 20 tractors
Currently we are in the third phase field testing which was
begun in the fall of 1984.
In order to accumulate the minimum
150,000 miles required this phase will have to last until March
1986.
However IH is concerned even at this relatively early
stage in the field out unsatisfactory on the test fleet
testing that this test series may also turn results Recent inspections of brake systems
show that iron brake drum material is being
transferred to and embedded in the brake block This accelerated
scoring seriously shortens the life of the drum
FURTHER TESTING NEEDS
As a result of this development IH believes it may not have found a suitable asbestos brake lining substitute even by March 1986 and further development and testing will be necessary after that date In addition it should be emphasized that once a
suitable substitute has been found through this testing program
another two years is required to release specifications procure material schedule and begin production with these materials The enclosed time chart Attachment B shows graphically the
number of steps that must be taken and the amount of time required
for each stage of the process
It should be emphasized that this testing program covers cam
brakes only
This system is used on the greatest number of
vehicles produced by IH However substitute materials must still
be found for other brake systems used by a smaller number of
vehicles materials
such as wedge and highway cam brakes have not yet been developed for these brake
So far test
systems
IH
is concerned that the low volumes involved with these systems may
not provide enough economic incentive perform the necessary research and
for brake manufacturers to
development on substitute
materials
containing materials will also
driveline parking brake applications used with all IH hydraulic service brake
located behind the transmission and are
have These
to be replaced in
brakes which are
systems
designed
are drum brakes to restrain the
driveline upon actuation of a structural integrity is crucial
hand lever
In this application
for linings because they must meet
requirements for grade holding in order to be certified to Federal
Motor Vehicle Safety Standard FMVSS 105
Finally while it is true that all IH hydraulic vehicles
use asbestos linings in type service brakes disc pads
currently use approximately
an insulating layer of containing 16th of an inch thick between the wear
material material
and the steel backing plate IH's suppliers are currently testing
possible strength
substitute
materials
with
the
needed to bond the asbestos
improved structural
Wear material to the
steel backing plate and to act as a thermobarrier
At this point however IH does not know how long it will take to
develop and qualify a satisfactory substitute material for the
insulating layer of asbestos in hydraulic brake disc pads Once
the field testing of substitute materials is completed it will
take another year for IH actually to incorporate these materials
into
its
products
through
the design
engineering and
manufacturing process
CONCLUSIONS
In recent years IH has voluntarily eliminated use of asbestos in most clutch facings and has eliminated approximately 90 percent of the asbestos in hydraulic service brakes IH's continuing effort
to develop asbestos cam brake friction materials demonstrates a commitment to elimination of all asbestos from our products
of consistent with preventing any degradation of production
performance
Although
a
federal
mandate
could
spur
the
introduction of more substitute material candidates by the
materials manufacturers heavy vehicle manufacturers such as
IH will require between three and a half and four years lead
time
to
test
and
incorporate
new
materials
into
their
products such new materials are developed
In summary IH would make the following points
1
IH's asbestos substitution program is proceeding as
rapidly as new qualified substitutes are made available to it
2
Substitute materials suitable for all vehicle applications
have not yet been found
3
For economic reasons substitute materials may not become
available for aftermarket service parts
4
IH will need three and a half to four years of lead time to
develop and produce vehicles with qualified substitute
materials
International Harvester pp 1-5
7 te
.71
Mr. Eaton
P.O. Box 595
Galesburg MI
49053
.
oo
113857
INTERNATIONAL HARVESTER March 8 1984
ATTACHMENT A
RE
Asbestos Brake Lining For Tractor Application
Dear
As you know IH has a program to evaluate asbestos linings on
tractors for fiscal year 1984. Over the last several years OSHA has lowered
the exposure limit of asbestos in the workplace Recently they proposed to
reduce the PEL permissible exposure level to .5f In addition they
intend to explore the feasibility of even lower limits of .1f All this has encouraged lining manufacturers to focus
.2f nearly
and all
their development dollars on asbestos materials Presently there is virtually no new developments with conventional asbestos based materials
Our work to date has consisted of evaluating approximately 30 field test
installations with various materials along with proposed trailer
combination tests at our test track
Recently however asbestos submissions
we learned under failed to live up to
field conditions that all advertised claims and desired
customer expectations As submissions are undergoing
a result in order to correct these problems compounding changes in one form or another
all Tne
new materials if approved will then make our asbestos field test obsolete Based on this we have decided to temporarily stop and completely
reassess our goals and the administration of this program The goals and
guidelines are
1. IH remains committed to pursue the qualification and release of asbestos materials on tractor models in an expeditious manner
>. The asbestos lining evaluation is starting over with all lining suppliers back to square one Before any material will be accepted at
IH for controlled vehicle tests or fleet tests the dynamometer
screening results must have been approved by our brake suppliers
3 The material has to provide equal to or nopefully superior lining and
.
i drum life characteristics when compared to ABB 551
4 The material has to have minimum coefficient of friction and yet be . certifiable
5 We are willing to consider AL changes in order to achieve maximum
life dyno performance and standardization willing to consider rerating an axle in order
In addition
to certify the
we are
longest
life materials
6 Front and rear materials do not have to be the same
7. The lining manufacturer has to convince the brake supplier that their
material is worthy of further consideration during the screening phase
i of the evaluation Communication however during the screening phase
should not be limited to only the lining and brake supplier I do want
.
to be made aware of all developments which include test results
failures compound changes etc. This information can be transmitted to
me by either the lining manufacturer or the brake manufacturer or both
8. Coverage
AXLE
LOAD
RATING #
RANGE ( #
12,000
8,10-12,00 8,100-12,000 8,100-12,000
20,000 20,000
16,160-20,000 16,160-20,000 16,160-20,000
CURRENT PROD BRK SIZES & LININGS
'
15 551
..
16-1 D39A
CURRENT PROD PWR
20x5-1
5-1
.R RADIUS
RANGE " 18.6-21.1
18.6-27.1
Screening Phase
The brake suppliers are to screen recommendations After screening the
potential
number of
candidates and make their
lining candidates will be
reduced to a maximum of two The materials selected will then advance to
the IH vehicle and fleet test phase
The screening test by lining
manufacturers and brake suppliers is to include
1 Dynamometer certification
ane
2
Torque curves
2
3 _
Wear test
4 Structural integrity
5 Lining sample tests
-3-
In order compare the
standardize the tests of , 2
various linings 3 & 4 as much as
an effort was made -
possible Test 5 Lining
Sample Tests are in some cases proprietary procedures brake manufacturer They include specific gravity gogan
required by each hardness acetone
extraction swell growth fast and chase test lining stability Mu vs.
temperature pressure and speed The results are to be reported to me
similar to 1 2 3 and 4
1. Dynamometer Certification Run per FMVSS
Report 50 mph
retardation fade and recovery Note that all dynamometer tests are to
be conducted with
. a Rolling Radius Range
-21.1
!
D
Cast drums
- Front drum weight
- Rear drum weight
55-65 lbs 105-115 lbs
c
Cam rotation - same
2. 2. Torque Curves Run 20 50 and 60 mph at axle rated loads of 12,000 lbs front and 20,000 lbs rear Plot chamber pressure vs. torque
3 Wear vs. Temperature
a
D
to Measure weight of each shoe and lining assembly the nearest gram
Measure shoe table and lining thickness in six equally spaced
(
locations per block
c
Measure drum inside diameter at open end center and closed end
Repeat at from first measurement
d
Install thermocouple in the center of each block == recess in
lining .040
e
Air flow should be set at 2200 min at 75 to 100 F
f)
Run all snubs from 40 mph to 20 mph at 7 sec Axle load for
fronts is to be 12,000 lbs and 20,000 lbs for rears
burnish g
Condition for wear test by running the lower portion of 121
200 stops from 40-0 mph @ 10 sec- IBT 315 to
n
Run 2,000 snubs at 250 1,000 snubs at 350 1,000 snubs at
450 1,000 snubs at 600 and 1,000 snubs at 250
:
1
Measure and weigh shoes and drums between each temperature interval
including burnish Note lining and drum condition Report wear in
weight of material lost and amount of material worn Reseat the
lining thermocouples to .040 depth after each measurement
4 Structural Integrity
a
Static Test
Place lining with ends down arc up on a flat
surface or parallel blocks Apply a downward force at the center
of the arc
Record force lbs and deflection in to break
'
lining Compare with 551 and D39A b Dynamic Test We are currently working with the brake supplier to
develop and verify a dynamic lining structural evaluation at nigh
temperatures approx 500-550 This should be resolved in
a
approximately two weeks| e
July , 1984 or before - Begin submission of final the brake suppliers to IH Finalize by August :
screening
data
October , 1984 - IH vehicle tests complete November 1 1984 - IH field test installations complete March , 1986 - Field tests complete 150,000 mile test
April 1 1986 - IH Engineering asbestos material recommendation
from
Meeting this tight schedule is extremely critical in order for the
timely completion of our vehicle tests Also it is our goal to obtain
approximately 100,000-150,000 miles on each field test unit
Please
indicate your willingness to participate in this program and meet tne
timeframe indicated in a letter to me no later than March 20 1984
Sincerely
)
Engineer
Foundation Brakes
ACTIVITY
I. VENDOR MATERIAL
SUBMISSION
II ENGINEERING VEHICLE TESIS
III CUSTOMER FLEET TESTS
ATTACHMENT B
SCHEDULE FOR ELIMINATION OF ASBESTOS FROM BRAKE LININGS AFTER_SUCCESSFUL AFTER_SUCCESSFUL MATERIAL DEVELOPMENT
*
0 4 8 T 16 20 24 29 32 36 40 44 48
|
|
i
J
:
SCHEDULE CONSTRAINTS I. MATERIAL DEVELOPMENT
(+
{ {
7
+
|
II TEST RESOURCES
III ONE YEAR MINIMUM REQUIREMENT
FOR FLEET TESTS
IV ENGINEERING DESIGN AND SPECIFICATIONS
|
"
|
i
IV COMPLETION OF VEHICLE TEST AND
FLEET TESTS
V. MATERIAL PROCUREMENT AND SCHEDULING
| j
V. ONE YEAR STOCK BALANCE
|
VI PRODUCTION IMPLEMENTATION
(|
VI RECODES MISBUILDS
VI OSBSOLESCENCE
* MONTHS FROM PROMULGATION OF FINAL RULES
+ A FAILURE HERE WOULD FORCE SCHEDULE BACK TO ZERO MONTH AWAITING NEW SUBMISSION OF MATERIAL FROM VENDOR
International Harvester Att 1 pp 1-6
72
As
a manufacturer of automobile and truck brake drums we have
dynamometer testing experience with both asbestos and asbestos lined drums We have noted several areas deserving
of comment and the Agency's concern prior to final rulemaking
First truck brake drums with asbestos linings appear to be more load sensitive than ones with asbestos linings Our testing indicates medium friction asbestos linings may not have as high a load rating as medium friction asbestos type
linings
In order to meet dynamometer requirements of FMVSS 121 for effectiveness fade and recovery a higher friction rating for asbestos linings will be required than for asbestos lined drums with a given axle load What we have seen would indicate that for equivalent friction ratings asbestos linings seem to be less effective than asbestos type
A less effective lining means that for given vehicle deceleration the air pressure required to effectuate a stop will increase Further with increased pressure required to brake
it can be expected that the fatigue life of the brake drum will proportionately decrease Further there will result in all probability an increase in the percentage of cracked
brake drums as a result of increased use of asbestos
linings as used in current configuration and material speci-
fications
On the other hand Motor Wheel Corporation has also noted that because of reduced aggressiveness of asbestos linings brake drums will according to our dynamometer tests have an increased wear life This increased wear life however is
only beneficial if the brake drums do not crack
Motor Wheel's testing is not extensive enough to formulate any final conclusions However we do recommend extensive testing
be undertaken to
asbestos linings
decisively
on vehicle
determine the effect of non-
brake performance and brake drum
life
Motor Wheel Corporation pp 1-2
73 General
It is Rockwell International's experience that economically and technically feasible asbestos substitutes are not developed qualified and available to cover the spectrum of vehicle brake applications Rockwell has had a substantial program underway to incorporate asbestos materials in the production of heavy vehicle brakes This program includes test and evaluation of both prototype and production asbestos brake lining The asbestos lining formulations and brake applications must not only meet our internal test requirements and the requirements of our brake customers but also the specific requirements of the National Highway Traffic Safety Administration's Federal Motor Vehicle Safety Standard No. 121 49 571.121 Rockwell International however as a purchaser of brake blocks and other lining materials for inclusion in foundation brakes is limited by the availability of asbestos materials developed by the brake
lining manufacturers
In many instances asbestos brake lining is unavailable to us because the materials are not fully developed at this time Basically the problem has been in finding materials to meet the test performance and durability requirements for many heavy vehicle applications Rockwell has . experienced unacceptable durability and performance problems with a number of the asbestos formulations furnished for on- and highway vehicle
test programs
It should be pointed out that and qualification for each of does for the very high volume
it takes as much the small volume vehicles
time for development test vehicle requirements as it
The following two sections Rockwell Asbestos Lining Program for OnHighway Heavy Vehicles and Rockwell Asbestos Lining Programs for Highway Heavy Vehicles will summarize the current status of our non-
asbestos development
Rockwell Asbestos NAB Lining Program for Highway Heavy Vehicles
As shown on Exhibit I attached the average yearly production estimate of heavy vehicles is approximately 652,000 units Of that number approximately 56 are highway vehicles These highway vehicles encompass three market segments and include heavy highway trucks and trailers and transit and intercity coaches
Our NAB lining development for the highway vehicle market has been in process for over five years in conjunction with our lining suppliers and our heavy truck bus and trailer manufacturing customers which include Mack Ford Kenworth IH GMC Truck and Bus Freightliner Peterbilt TMC Greyhound Trailmobile Great Dane and Budd Our NAB program consists of
as our internal test programs for performance and durability well as the
qualification of Rockwell brakes with NAB lining under the provisions of
FMVSS No. 121. During this period four replacement NAB lining formulations have been identified tested and integrated into highway vehicle applications and certified to the requirements of FMVSS No. 121. This
represents significant NAB substitute progress as these applications include
potentially high volume application areas On the other hand however we utilize over 24 asbestos formulations from primarily two brake lining suppliers for our complete highway brake requirements Therefore numerous additional lining formulations must be developed and certified to satisfy
all highway vehicle demands The certification of the base formulations
must be made on a wide range of vehicle applications with different braking
systems and different basic foundation brakes including cam drum brakes wedge drum brakes and disc brakes
It should also be pointed out that in certain highway vehicle categories such as mass transit coaches and braked trucks or trailers the NAB
linings required for the demands of these applications are in the undeveloped category at this time These vehicles represent a relatively small but important portion of all the highway vehicle market
For the majority of highway applications NAB materials are being developed
that can over a reasonable period of testing qualification and NAB lining
production build replace asbestos in the major portion of the heavy commercial vehicle market This would include highway trucks and on-
highway trailers as shown on Exhibit , which total approximately 54 of the
heavy vehicle market As stated however we would currently exclude
braked trucks and trailers as well as transit and intercity coaches
'
which as a group represent a small portion of the highway market
Rockwell Asbestos NAB Lining Program for Highway Heavy Vehicles
The typical yearly production estimate of vehicles that falls into the category of highway is approximately 44 of the heavy vehicle market This includes such vehicles as cement mixer trucks moving vehicles crane carriers ore haulers lift trucks agricultural vehicles This program has also been underway for over five years with our lining suppliers and such major highway customrs as Caterpillar FMC Grove Chalmers and
John Deere
As this time we have been unable to find NAB materials which are equivalent in performance and durability to asbestos linings required to satisfy most highway braking requirements The highway vehicle braking requirements are generally quite severe These vehicles cover a wide range of vocations from industrial lift trucks to giant ore haulers The vehicles vary as to width length and centers of gravity as well as loadings and operating conditions all impacting brakes
Much of our brake lining suppliers NAB development and in turn Rockwell's NAB lining qualification to date have involved low and medium friction level classification applications to the higher volume highway trucks and trailers While the result is converting the largest vehicle category in the shortest time to NAB materials it must be recognized that considerable development test and qualification still is ahead the highway vehicles as well as certain highway vehicles such as transit coaches
Rockwell has just begun receiving devleoped friction NAB materials for test and certification Completion of this process to cover the complete spectrum of specialty vehicles is a number of years away
Summary and Recommendations
The NHTSA Federal Motor Vehicle Safety Standard No. 121 for braked vehicles initiated in the early 1970's required brake certification to the existing asbestos commercial vehicle brakes Even with the already existing asbestos lining formulations it required an extended period of time to qualify and certify brakes and brake applications covering the multitude of heavy commercial vehicles Adding the need to develop
and test complete new material formulations NAB results in a task that is a greater time consumer Part of the time consuming complexity is the large number of vehicle manufacturers a greater number than normally
understood These exceed over three hundred in number and range from
very large truck manufacturers to small specialty vehicle manufacturers
Rockwell estimates that within the next several years it will be in a
position to offer NAB medium friction lining formulations to our vehicle manufacturers for most of the high volume highway heavy truck and trailer brakes This would assume that the upstream lining manufacturers
continue their substitute NAB formulation efforts and then can furnish
quantities of NAB materials Considerable additional time however will be required to complete work on the higher friction NAB formulations for the wide variety of vehicles such as buses and the large highway vehicles
Rockwell International is ) continuing to expand its NAB lining applications and production releases based on the four high volume highway material formulations already approved 2 continuing to test and evaluate new onhighway NAB lining formulations in the engineering and development mode 3 initiating highway prototype NAB lining field test programs on haulers loaders forklifts 4 continuing to aggressively support vehicle manufacturers field test programs and 5 accelerating test efforts on newly developed NAB materials in order to expand the application approval base
YEARLY PRODUCTION ESTIMATE
OF THE HEAVY VEHICLE MARKET
fi
-
652,000 UNITS
Includes
On Highway Heavy Trucks
braked straight trucks braked tractors braked fire engines braked military trucks etc.
Highway Heavy Trailers
braked vans braked reefers braked flat beds braked liquid tankers etc.
Coaches
braked transit coaches braked intercity coaches
Highway Heavy Vehicles
Some move from site on the highways
trucks braked crane carriers ore haulers haulers
moving vehicles agricultural vehicles etc.
braked mixer lift trucks earth-
MARKET SEGMENTS
Highway Heavy
Trailers
145,000 Units
we LoS
>
<
Highway HeavyDuty Trucks 209,000 Units
Coaches 7,000 Units
Highway
Market - 56
(Ae
Highway
Market - 44
Highway HeavyDuty Vehicles 291,000 Units
Based on an average production year in each category
we
Some of these large vehicles incorporate drum or disc hydraulic
foundation brakes
Rockwell International pp 1-6
BFGoodrich uses several types of brake lining other than
asbestos containing linings in our brake systems including
resin bonded metallic and sintered linings
Due
to
the
performance and wear characteristics of the used in our brake systems and our customer
various linings requirements we
currently containing
supply about 80 of our systems with asbestos linings 15 with resin bonded metallic linings and
% with sintered metallic linings
Our Division has an ongoing program to evaluate new types of
asbestos free lining materials
To date we have not been able
to find suitable asbestos free substitutes for the asbestos
containing linings used today in the majority of our braking
systems
The major stumbling block
linings for use in our
in finding acceptable asbestos free braking systems has been inferior
performance and wear characteristics versus asbestos containing
linings The asbestos free linings evaluated to date fade more
than asbestos containing linings
Both characteristics are
undesirable
A second hurdle is in finding asbestos free lining materials to evaluate The highway segment of the automotive market is
a very small segment of the total market and there is little
research aimed at producing an asbestos free alternate lining
for this market
BF Goodrich Company pp 1-2
75
In determining whether a product is a suitable substi-
tute for asbestos in brake applications the factors to be taken
into account include the constant coefficient of friction the
rate of wear the thermal stability the strength the absence of
scoring to the drum or rotor the noise generated by and the cost
of the products being compared From our research asbestos has certain unique qualities
which have as of 1985 not yet been duplicated for most brake applications in terms of friction performance thermal stability wear resistance strength and cost See e.g. Loken Halvary
Asbestos Free Brakes and Dry Clutches Reinforced with Kevlar
Aramid Fiber Paper 800667 SAE 1980
We understand that the asbestos fiber in friction mate-
rials for brake application is chrysotile That fiber has special characteristics including its ability to stiffen and strengthen the resin matrix which makes up the brake lining and can maintain these properties even under high temperatures Pye A.M. A Review of Asbestos Substitute Materials in Industrial Applica-
tions Journal of Haz Matls 3 125-147 1979
glazing
High wear on brake linings may cause what is
which can cause a reduction in the coefficient
termed of fric-
tion This reduction is avoided by allowing for a slow alteration
in the brake lining materials The chemical change brought about
by heat to chrysotile fibers restores the friction surface so as
to reduce or eliminate the glazing effect Nicholson W.
Investigation of Health Hazards in Brake Lining Repair and
Maintenance Workers Occupationally Exposed to Asbestos Task I Brake Materials Products and Usage Draft report submitted to OSHA by Environmental Sciences Laboratory Mt. Sinai School of Medicine New York January 1979
The possible substitutes for asbestos in brake applications metallics and organic fibers are substantially more expensive than asbestos Further metallics cause greater rotor or drum wear and are quite noisy Aramid fibers tend to
clump thereby requiring certain mixing procedures Loken SAE
1980 The petition of the Natural Resources Defense Council NRDC misstates the facts when at page fifteen of the Petition
it asserts that reinforced brakes have the same basic
formulation as asbestos brakes and therefore production techniques already developed for asbestos brake manufacture can
easily be retained It is importantto note that NRDC's support
for the quoted phrases is Loken However Loken offers no support for the NRDC assertion
Other possible substitutes include glass which can melt at high temperatures reached in normal brake applications
and be converted through the heat to a form of lubricant ver-
miculite which is platy rather than fibrous and therefore does not have the capacity to strengthen the resin mix which asbestos does and silicon nitride and carbon composites which have limited specialized applications such as the Concorde SST or racing cars and are very expensive
The foregoing research does not suggest the absence of progress in attempting to find substitutes for asbestos in brake applications For example metallics have been substituted for asbestos in disc brakes front brakes in downsized cars However they are not suitable for rear drum brakes on most American cars and trucks because they cannot be processed into
the required arcuate shape In any event more testing must be
done on metallics before they could be regarded as safe substitutes for asbestos in brake applications
With respect to the substitutability of other products for asbestos in brake applications we enclose a portion of a report prepared by John W. Kourik Chief Engineer Brake Products and presented to the 1980 Society of Engineers Congress in Detroit Michigan Mr. Kourik concludes that while efforts are being made to find replacements for asbestos in brake applications those efforts have not yet been achieved
In determining whether to cause the discontinuance of asbestos in brake applications the EPA must take into account
not only the uncertainty associated with the health risks claimed
to be attributable to exposure to asbestos but also the fact that there is yet no reliable substitute for asbestos as a component
for brake lining in most brake applications To accept substitutes without thoughtful and reliable testing programs invites a significant safety hazard for drivers and passengers of vehicles and bystanders as well Moreover it is neither prudent nor costeffective for EPA to require a complete substitute for asbestos
on all brake applications Brake systems are very sophisticated and contain many components each of which must have characteristics perfectly compatible with the
characteristics of the other
components
One cannot reliably remove one
component of a brake
system
such as friction material
containing asbestos and re-
place it with another without
considering the effect such sub-
stitute will have on the brake
system's performance coefficient
of friction durability maintenance requirements and noise pro-
duction
Wagner Division Att 1 pp 1-6
CONSIDERATION ON REGULATING THE
76
WAGNER
COMPOSITION OF BRAKE LININLININGG
John W. Kourik
Chief Engineer Brake Products Wagner Electric Corporation
1980 SAE Congress
Detroit Michigan February 25 1980
STATE OF ASBESTOS LINING
recent The most
press industry releases and magazine articles imply that
there is an almost immediate capability to eliminate asbestos from brake lining
Such claims are not representative of the true
state from asbestos linings We base this belief on the small number of test materials that we have
had from lining manufacturers We'll help you look at the overall scope of the
market and the need to evaluate the success or failure of the tests of these
materials before concurring in the validity of the development claims We also
must determine their true availability facturer and use these findings to see
based if we
on committed tooling by the manu-
can procure the material needed to
service a very extensive market
Let's look at the number of applications that need to be covered by
D friction materials in the braking area only
Friction requirements are
different for a variety of vehicles because of the different types of appli-
cations
the type
the speeds or service
at which they operate the frequency of brake applications and the durability needed to have long intervals between
relining and servicing
Wagner is extensively involved in supplying original equipment brake
assemblies aftermarket linings and replacement shoe and lining assemblies
Our aftermarket program is one example of the complexity of a changeover We require 216 dimensionally unique segments for drum brakes and 134
unique disc pads for our passenger car replacement program even though this
program already incorporates a high degree of standardization and simplifi-
cation
We have surveyed our current varieties of lining compounds and the sources for these materials In these several categories we have a total of 50 materials that we purchase from 10 different sources
ORIG EQUIPMENT +
AFTERMARKET APPLICATIONS
NUMBER OF LINING
COMPOUNDS
SOURCES
PASSENGER CAR
20
5
TRUCK SEGMENTS
18
5
TRUCK BLOCKS
16
6
CUMULATIVE
50
10
Let's look at the characteristics that are needed for OEM and replace-
ment materials Most of these are explanatory
DESIRABLE CHARACTERISTICS OF A SUITABLE LINING MATERIAL
STRUCTURALLY SOUND
NO MORNING SICKNESS *
LONG ROTOR LIFE
LONG WEARING
CONSISTENT FRICTION - HOT & COLD
ACCEPTABLE NOISE LEVEL
ACCEPTABLE WATER RECOVERY
PHYSICAL FLEXIBILITY FOR ATTACHMENT
TO SHOES USING STANDARDIZING SEGMENTS
LIGHT WEIGHT
* Erratic braking or grabby lock up on first stops
Now consider the variety of brake designs used on old and new vehicles
PASSENGER CAR & TRUCK
HYDRAULIC BRAKE TYPES
TRUCK TRACTOR & TRAILER
AIR BRAKE TYPES
INDUSTRIAL BRAKES
EXTERNAL
SERVO
CAM
AIR
SERVO
DISC
DISC WEDGE
HYDRAULIC SPRING SOLENOID
There is considerable technical literature available on the subject of brake goemetry and effect of friction materials on design performance and speed sensitivity We have submitted several of these and their bibliographics
to the CPSC dockets for reference purposes
Considering all of the above brake types it appears likely that only the passenger car and light truck disc brakes will have a suitable asbestos friction material available in the reasonably near future
There will be a long transition as development efforts continue to be directed towards the availability of
1 a substitute material that will allow vehicles to remain at or exceed today's safety level
2 a suitable substitute for current asbestos based materials at a
reasonable cost 3 a long wearing lining material that also causes minimal drum wear or
little rotor wear
At this time we have an insufficient number of samples to predict a realistic target date for conversion to asbestos strip segment or block
material We expect this to be at least several years away We look with askance at the press releases extolling the imminent availability of non-
asbestos lining materials without citing the limited number of applications
covered
Wagner Division Att 2 pp 1-5
The
19.2 19
How asbestos
grand total of lives saved if EPA grants the petition now is
in the occupational field and 0.2 in the general public sure must EPA be that there is a satisfactory substitute for
brake materials to make a decision on less than 20 lives per
year
108 There are about
motor vehicles on the road traveling about
208 208 miles per year
My experience has been that a cag needs new
each brakes at about ^ 10 miles This calculates to 25 x 10 brake jobs
Let us assume that it takes ten catastrophic brake failures to
per year
actual a fatality
I expect that the
number is somewhat less
cause
200 added failures out of 25 x 10
brake jobs will exactly balance
Thus
the savings postulated from the proposed ban
That requires a
confidence of 99.9992 that any proposed substitute is at least equal to
asbestos as a brake material Does the Agency have that confidence or
data to suggest that such a conclusion is secure
is no assurance that any new forced substitution of materTiahlesre woceurltdaibnelybetter than 99.999 successful day after day year after
year
John T. Barr pp 2-3 4
78 Finally testimony submitted to the EPA primarily in 1984 is sharply
critical of metallic friction compounds in general These compounds
represent the first generation of asbestos friction materials that has experienced wide distribution While analysis of individual semi-
metallic formulations and commerical products is valuable the EPA should
not rely entirely on evaluations made on earlier models Rather contact firms whose entire business or the majority of their
it should business
depends upon manufacturing metallic friction products Such companies market and sell products to customers worldwide with primary emphasis on
Canada Europe and the United States These firms technical perspectives on the advantages disadvantages and state of the art in metallic
brakes may differ from the previous EPA testimony
Engelhard Corporation p 6
79
We believe that it is useful for your agency to encourage the development of
nonasbestos brakes but not at the expense of brake performance In only
one of the vehicle brake categories light and medium disc brake pads did
feel that a satisfactory performance record was evident for nonasbestos
you
did not have sufficient experience
brakes The other vehicle brake categories
with the performance record or found that the products performed erratically
Motor vehicles are the leading cause of death from injury They are the
of loss of life from age 1 to 44 and the leading cause of loss
leading causes
Even a small amount of
of preretirement years of life in the United States
erratic brake performance could easily outweigh the potential morbidity and
mortality saved by reducing ambient air asbestos by 0.23 to 1.3 percent Much
of this decrease could be gained by adequate work practices during mechanical
servicing of brakes
A reduction in ambient air elimination of asbestos in
should be strongly weighed
asbestos levels should be encouraged but the brake pads as a means of accomplishing this goal
against the safety performance of alternatives
Center for Environmental Health p 1
F. Special Considerations for Existing Vehicles
80
The matter of replacement brake linings for older model vehicles still in service warrants additional discussion The general control approach to asbestos in brake linings is to develop substitutes This approach is acceptable for new vehicle designs because brake systems can be engineered around the characteristics of the substitute Substituting asbestos brake linings without redesigning the brake system may result in reduced lining durability adverse effects on other brake system
components and even increased stopping distance Thus using
asbestos substitutes in brake linings without carefully evaluating the consequences could result in trading reduced health risks for increased traffic safety problems Accordingly the
continued use of containing replacement brake linings
with proper control measures may be a neccessary alternative for
the period of time vehicles with asbestos dependent brake systems are a significant segment of the vehicle population
Motor Vehicle Manufacturers Association Att 2 pp 13-14
a
TV TV 71 71 71
81
As owners of antiques collectors and special
interest automobiles dating back to the 1920's we strongly object
to the use of semimetallic or aramid fiber brakes especially in our
older automobiles which are not equipped with power brakes These asbestos brakes do not provide adequate stopping distance when
they
with
are cold and this
front disc brakes
is much more Furthermore
pronounced in cars equipped
semimetallic and aramid fiber
brakes cost
would put a
two to three times more
hardship on some of our
than asbestos brakes which
members who own several olaer
automobiles
Classic Cars of Ponca City p 1
82 POTENTIAL IMPACT ON SERVICE PARTS
The possibility of a total ban on containing components
raises another concern that of the impact of such a ban on the
availability
of
market
service
parts
if
worn
containing components must in the future be replaced with
containing components
Aftermarket demand for service parts steadily decreases as the age
of a vehicle increases beyond the peak service years
IH fears
that
parts
suppliers
will
not
be
willing
to
spend
the
resources
for
necessary to develop and produce asbestos substitutes
shrinking markets for production brakes
There simply
may be no economic justification for such an investment
International Harvester p 5
83
Asbestos replacement products are are available on the market some of which are of satisfactory quality but these these always have a lower friction coefficient use of these products is therefore only possiblepossible on brakes which provide for
this installation from the outset
It is not always possible possible to accomodate brakes capable of being fitted with
asbestos linings on small vehicles On use vehicles asbestos linings
must never be replaced by asbestos linings this could substantially modify braking performance either immediately or following partial wear
and could therefore entail considerable risks to safety
Renault USA Inc. p 2
84
Vehicles in use
are more than hundred brake and brake lining
There
sizes
designed for vehicles still in use that must be
serviced It would be a monumental task with substantial
economic involvement for service part suppliers to
develop asbestos replacements for those applica-
tions
Motor Vehicle Manufacturers Association Att 3 p 8
85. One particular problem that concerns us and that we feel must be highlighted is the continued availability of containing parts for vehicles currently in production or no longer in production which employ such parts Ford Motor Company through its Parts and Service Division is a major marketer of aftermarket disc and drum brakes and related brake system parts
Currently the Company's aftermarket parts distribution system has on hand some 51,000 asbestos brake parts in stock at eight depots
in the U.S. and Canada These parts involve 192 different brake system designs We supply these parts mostly pads shoes discs and drums for cars and trucks produced by the Company between 1957-1985 -- a period of 28 years It is imperative that parts for these vehicles continue to be available to our dealers and
customers for the remainder of the product's useful life and that
any regulatory program envisioned by EPA not interfere with that
need
Car and truck brakes are sophisticated systems made up of parts which are carefully matched to function compatibly with each other so as to provide appropriate braking characteristics for their vehicles under a wide range of operating conditions A brake system is not simply a collection of disparate parts -pads shoes discs drums etc. The pads and shoes of car and
truck braking systems that use asbestos friction materials have very different properties from the pads and shoes of those that do not contain asbestos One cannot simply use a asbestos substitute brake shoe in conjunction with a drum that was designed for an containing friction material Likewise a disc brake that was designed for a metallic friction material will not perform satisfactorily if an containing pad is substituted A whole host of performance noise durability and other problems may occur if a friction material is introduced into a system which was not designed to employ it
Ford Motor Company p 2
, CRITICISMS OF NRDC PETITION AND EPA RESPONSE
<7 1
A. NRDC Petition
COMMENTS ON THE
86
- NRDC PETITION TO THE
ENVIRONMEHTAL PROTECTION AGENCY
TO BAN THE USE OF
ASBESTOS IN AUTOMOBILE BRAKES
PETITION SECTION I. INTRODUCTION
The introduction of the NRDC petition emphasizes that the
and cancer has been conclusively
link between asbestos exposure since the early 1950's While
demonstrated by epidemiologists
of sufficient
this
may
be
true
for
certain
occupational
exposures demonstrated
between
length and quantity no association has been
exposure to brake dust and cancer
The introduction expresses an underlying assumption that no
safe threshold levels of exposure to asbestos can be established
which is the subject of intense debate in
This is an assumption
is directly contrary to the
the occupational health community community and
assumption made by NIOSH in establishing threshold limit values
The second expressed assumption assumption of the introduction is that
feasible substitutes are available for use in brake linings However as discussed in other other portions of our submission this is not completely true
PETITION SECTION
IV
THE CONTINUED USE OF ASBESTOS IN VEHICLE BRAKE LININGS POSES AN UNREASONABLE RISK TO HEALTH
is The
petition
asserts
that that
asbestos is one of the largest human cancer in the United States
single causes of environmental environmental
No reference is cited to support this claim There no
because asbestos has has not been associated with human
reference
cancer outside of specific occupational occupational settings
The leading
environmental causes of cancer cancer are smoking diet and other
lifestyle factors not asbestos asbestos
1978 Health Education and Welfare paper cited announcing
The
deaths over the next several decades is
that 17 percent
unpublished
of cancer
scientifically
inconsistent
and
frequently
reviewed
and
an
document The report remains peer
inaccurate
unaccepted in the scientific community
A.
Increased Risk of Disease
This section stresses the mortality statistics associated with asbestos disease The studies from
which the statistics are taken relate to insulation workers and are not relevant in the context of friction
materials It is the amount and length of exposure that is significant not the exposure per se
subsequent The assertion is made that animal inhalation studies
demonstrate no significant difference in the effects of
various types of asbestos NRDC cites a 1974 study by
Wagner as authority for that statement The petition
neglects to point out that numerous
animal 4,5
experiments including the work of Gross
demonstrate precisely the opposite These latter
studies would tend to indicate that chrysotile the only
type of asbestos used in brakes is significantly less
pathogenic than other types of asbestos fibers
B.
Brief and Term Exposure to Asbestos
This section stresses that both brief and term
can result in asbestos disease
exposures
of the sources cited has anything to do with
Again none
There is no evidence in the medical
friction products
literature demonstrating any significant risk from
either brief or term exposure to friction products
1
Health Risks From Asbestos Brake Products
This section begins by asserting that brakes create substantial exposures to asbestos which constitute a
serious health threat not only to brake workers but to
the general public No scientific basis is referenced
for this broad statement
The petition asserts
that a fraction of
process The reader conclusion that this
that numerous studies have shown asbestos fibers survive the braking of this sentence might draw the
fraction is a significant one
The petition neglects to indicate that the three principal studies the subject indicated precisely the
opposite Anderson found less than .02 percent of
the fibers survived the friction process Lynch 8 found
less than 1 percent and Jacko found less than .3
percent More formed in the
than 99 percent of the
friction process into
fibers are transa nonasbestos
nonfibrous dust
This section stresses the ambient air particularly levels are increasing A
danger of asbestos fibers in
in urban areas where asbestos
private letter from Dr. Wm
Nicholson of Mt. Sinai New York City is cited as
authority for the proposition that
asbestos content in ambient air is
this from
increased automobile
brakes This conclusion is not based upon any published
evidence In fact there are several references
,
which indicate that less than 1 percent of asbestos
fibers in city core districts originated from disc brake
wear
The petition discusses the Jacko Bendix study and
cites it for the proposition that American vehicles release approximately 158,000 pounds per year of
asbestos into the atmosphere This misrepresents Jacko's findings 158,000 pounds represents the total estimated asbestos emissions potentially produced from
brake linings by the friction process Only 3.2 percent or 5,060 pounds of that was found by Jacko to be airborne asbestos fibers 85.6 percent of the asbestos emissions do not remain suspended and dropout
_
from the atmosphere'
This section goes on to discuss Rohl's 1976 study on
the asbestos content of brake dust
It notes that Ronl
found that more than 80 percent of the surviving fibers
were 0.4 micron in length but fails to mention that such short fibers are considered by many respected
medical authorities not to be pathogenic at all
12
This section of the petition concludes with the sentence
that the problem of exposure to dangerous levels of asbestos during brake servicing is substantial and that
he small asbestos fibers from brake wear can easily penetrate throughout the respiratory system and also migrate to other organs in the body
The conclusion is not supported by studies which
indicate that the smaller fibers present during brake
servicing are less
and more likely to
likely to be deposited in the lung
be removed by macrophages ,
Automobile Maintenance Workers Are At Particular Risk From Exposure To Asbestos Brake Products
This section argues that because of the airborne
mobility of these small asbestos fibers from brake linings a diverse group of people are at risk The petition includes garage mechanics bystanders tool
booth operators families of mechanics and persons
living in urban environments as the population at risk
The only two citations upon which this argument is based
are two case reports which purport to document a
mesothelioma in a pet whose owner was a mechanic and a brake mechanic's child who had mesothelioma The
latter case is not footnote indicates
a published case report but the
that this was communicated in a
letter from Barry Castleman to a person or persons unknown ' One case report of a pet and a letter from
Barry Castleman statements made
are scant support in this section
for
the
sweeping
This section concludes by alleging that recent
literature also documents mesothelioma among automobile
repair workers Greenberg's 1974
The first
report
literature cited is which found one mesothelioma
death in a motor mechanic Greenberg gives no
occupational history for the mechanic
The other case report cited is that by Langer in
1982 Support for the proposition that there are
two additional mesotheliomas in brake mechanics is allegedly found in Castleman's recent book on asbestos and a personal communication by Susan Daum to Castleman Yet important data on these cases are missing such that verification is not possible from these sources
alone
Thus there are only two cases of mesothelioma in all of the reported medical literature which allegedly implicate brake dust One of those Greenberg is
questionable
RTP
Motor Vehicle Manufacturers Association Att 1 pp 1-5
87. I - INTRODUCTION The stated reasons for the submission of the petition do not appear to be based upon irrefutable evidence Whether or not the occupational asbestos standards and the national emissions standards are insufficient to protect against unreasonable risk posed by asbestos in brakes is highly
debatable Further the availability of economically and technologicalltechnyologicaly
feasible substitutes for asbestos is an issue in which the friction
materials manufacturers are deeply involved The identification of such substitutes is a major ongoing program with the manufacturers and is not a completed program at this point in time
II - JURISDICTION
The FMSI concerns relate to plant regulations versus control of general public exposure to asbestos dust While one agency has proposed to tighten
eliminate worker exposure to asbestos another is being peritioned to
asbestos in friction materials The disparity between these two situations could well create implementation and economic problems for friction
materials manufacturers If asbestos is to be regulated out of friction
materials the manufacturers should not be saddled in the meantime with
compliance to new tighter regulations of asbestos in the workplace The
industry must know which direction regulatory activity will take
III - DESCRIPTION OF PETITIONER
No comment
37 37 0 0 0
IV - CONTINUED USE OF ASBESTOS AN UNREASONABLE RISK TO HEALTH
of
The FMSI does not necessarily agree with the credibility of the con-
clusions drawn from the evidence presented on friction materials in this section Therefore the FMSI reserves the right to comment in detail on
this section at some Suture date
V - SUBSTITUTES
Sufficient data is not available at this time on the substitute materials
to state that they do not pose a hazard in the workplace environment or to the general public We wish to cite a recent study by the Canadian Royal Commission on Matters of Health and Safety Arising from Use of Asbestos in Ontario and an earlier paper on asbestos Related Malig-
nant Mesothelioma
These comments follow follow
...
the producprodtuction ion
of of
substitute substitute
fibres
in
the
future should
increase the exposure of workers to long thin durable fibres
of dimensions similar
to those we have found hazardous for
asbestos we cannot be sure that serious health consequences
would not result To the face of the existing evidence we
believe it would be risky to allow the exposure of workers to respirable fibres longer than 5 microns with small diameters of any material if those fibres are likely to be very durable
in the lungs
It has been generally accepted now carcinogenic is a durable long and of less than 1.5 micron and length
that the fibre which is thin fibre the diameter of more than 8 micron
appearing critical
asbestos can appear been established as
A number of Fibrous materials other than
in this size and shope and indeed have Couse of mesothelioma in animals such as
glass fibres aliunde aliunde
silicon carbide and ~ tassium
tremolite
titanate
attapulgite
dawsonite
of metallic brake linings cited in Section - are The advantages
not necessarily supported by test results generated by friction materials
Manufacturers While certain of these claimed advantages may be true
where the application generates high braking temperatures they are not necessarily true for the average consumer
Total endorsement of Section B of the petition is not appropriate
since friction materials manufacturers produce disc pads and drum segments for passenger cars and light to medium trucks as well as brake blocks
for heavy trucks The claims made in Section b relate to brake blocks and cannot be ardorsed for all product lines Further actual experience to date has proven that substantial processing modifications and new
equipment are required for the asbestos substitute materiais
VI - A REQUIREMENT UNDER THE TOXIC SUBSTANCES CONTROL ACT
No comment
WWEEII
CONCLUSION CONCLUSION
oo
CONCLUSION
CONCLUSION CONCLUSION
CONCLUSION
No comment
Friction Materials Standards Institute Inc. Att 1 pp 1-4
Ce 10 10
88
The petition of the Natural Resources Defense Council
NRDC misstates the facts when at page fifteen of the Petition it asserts that reinforced brakes have the same basic
formulation as asbestos brakes and therefore production techniques already developed for asbestos brake manufacture can easily be retained It is important to note that NRDC's support for the quoted phrases is Loken However Loken offers no sup-
port for the NRDC assertion We would also like to point out that the statements by
NRDC regarding the risks associated with asbestos fail to take
into account the distinction between insulation asbestos which
is not involved in brake application and chrysotile fibers which
are
Wagner Division Att 1 pp 3 5
B. EPA Response
89. Second AIA wishes to comment on a major omission in the December
absence of any mention of the
19 response namely the complete
health effects of substitutes
for asbestos in brakes
Any
sub-
of
material or
proatteinotnialal system of regulation in which the use a
risk
stance may be prohibited for reasons rem lu as tetd it nocluadne unarneaesvoanlaubalteion of
of injury to health or the environment
from substitute materials
If this were not the
the risikts woruelsdultniontg be possible to say that any benefit had accrued
case
to society as a result of a regulatory action
Section c of the Toxic Substance Control Act TSCA specifi-
cally cites that substitutes for a substance must be given consideration in the context of section 6 rulemaking
C the benefits of such substance or mixture for various uses and the availability of substitutes for such uses
that a consideration of the availability of
While it may be argued
consideration of the health
substitutes does not necessitate a of the substitutes the immediately
following
section which evalua-
elfifsetcstsadditional factors to be considered would require an
tion of substitutes health effects
D the reasonably ascertainable economic consequences of the rule after consideration of the effect on the national economy small business technological innovation the environment and public health emphasis added
Section D is explicit in stating that ctohnesiednevriartoinomnent Ifanda psuubb-lic
health effects ofbananerduleinmufsatvorbe ofgivseunbstitute materials Section 6
stance
cD
is to be
requires
that
the
environmental
and public
health effects of would have to
such an action be considered and such consideration
take into account the environmental and public health effects of
the substitute materials Any other course of action would be ir-
rational and not permissible under TSCA
The entire Toxic Substance Control Act is framed within the context
action It does not permit the regulation
of reasonable regulatory
unreasonable risk
The intent of Congress in
of any risk but only
issue Section c of TSCA
passing the Act is specific on this
entitled Intent of Congress states
It is the intent of Congress that the Administrator
shall carry out this Act in reasonable and prudent
manner and that the Administrator shall consider the environmental economic and social impact of any action the Administrator takes or proposes to take
under this Act
Asbestos Information Association p 2
90
The Notice points out that there are 2,750 employees potentially
exposed during brake manufacture and 550,000 during servicing and repair
This last figure is greatly exaggerated for almost no one repairs or
services brake linings any more They are simply replaced and the old
ones are discarded with minimal exposure but let's play the game by your
;
rules and go with that number ~
John T. Barr p 1
APPENDIX A - LIST OF COMMENTERS
TRADE ASSOCIATIONS
Asbestos Information Association America Friction Materials Standards Institute Inc. Japan Automobile Manufacturers Association Motor Vehicle Manufacturers Association
VEHICLE MANUFACTURERS
Chrysler Corporation
Ford Motor Company International Harvester Renault USA Inc.
BRAKE MANUFACTURERS
BF Goodrich Company
Motor Wheel Corporation
Rockwell International Wagner Division
SUBSTITUTES MANUFACTURERS
Ashland Petroleum Company Du Pont Canada Inc.
Engelhard Corporation
Monsanto Company
MISCELLANEOUS
John T. Barr
Center for Environmental Health Classic Cars of Ponca City Stratford Citizens Against
Pollution
APPENDIX B - REFERENCES
Asbestos Information Association America
-
Letter to EPA dated March 7 1985
Ashland
-
-
Petroleum Company Letter to EPA dated March 14 1985
Attachment News From Ashland Petroleum Company February 8 1985 Carboflex Product catalogue
Press
release
Barr John T.
-
Letter to EPA dated January 15
1985
BF Goodrich Company
-
Letter to EPA dated March 5
1985
Center
-
for Environmental Health Department of Letter to EPA dated February 6 1985
Health
and
Human
Services
Chrysler Corporation
~
Letter to EPA dated March 13
1985
Classic Cars of Ponca City
-
Letter to EPA dated March 7
1985
Du Pont Canada Inc.
-
Letter to EPA dated January 23 1985
-
Attachment 1 - Breakthrough in Brake Performance Du Pont Magazine
-
Attachment 2 - Kevlar Demand High Canadian Metallic Sales Up
Du Pont News August 1984
-
Attachment 3 - Asbestos Disc Brake Pad Wears Like
Metallic Not Detrimental to Rotor Surfaces Du Pont News
-
Attachment 4 - Kevlar Relieves Tension Headache for Belleville
Maker Du Pont News June 1984
Engelhard Corporation
-
Letter to EPA dated March 13
1985
Ford Motor Company
-
Letter to EPA dated March 15
1985
Friction Materials Standards Institute Inc.
~
Letter to EPA dated March 13 1985
-
Attachment 1 - Letter to EPA dated November
13
1984
International Harvester
-
Letter to EPA dated March 15 1985
-
Attachment 1 - Letter to Mr. Eaton dated March 8
1984
Japan
-~
-
Automobile Manufacturers Association Letter from Tanaka Walders & Ritger Attachment 1 - Comments of the Japan
dated March 22 1985 Automobile Manufacturers
Association
Stratford Citizens Against Pollution
-
Letter to EPA dated March 12 1985
Monsanto Company
-
Letter to EPA dated March 15
1985
Motor Vehicle Manufacturers Association
~
Letter to EPA dated March 15 1985
-
Attachment 1 - Comments on the NRDC Petition to the EPA to Ban
Use of Asbestos in Automobile Brakes
-
Attachment 2 - Comments on Proposed Asbestos Standard of the
Occupational Safety and Health Administration May 24 1984
-
Attachment 3 - Alternatives to the Uses of Asbestos in Motor
Vehicles revised March 1985
-
Attachment 4 - Letter from the Friction Materials Standards
Institute to U.S. Department of Labor May 22 1984
the
Motor Wheel Corporation
-
Letter to EPA dated March 14
1985
Renault USA Inc.
1
-
Letter to EPA dated February 21 1985
Rockwell International
-
Letter to EPA dated March 18
-
Attachment 1 - Letter to U.S.
1985
Department of Labor May 25
1984
Wagner
-
-
Division Edison International Inc. Letter from McDermott Will & Emery to EPA dated April 4 1985 Attachment 1 - Response of Wagner Division of Edison International Inc. to the Petition of the NRDC re Asbestos Brakes
Attachment 2 - Consideration on Regulating the Composition of Brake
Lining February 25 1980
APPENDIX C- CROSS REFERENCES
Commenter Asbestos Information Association
Comment No.
1 22 24 89
Ashland Petroleum Company
13 50-53
Barr John T. 52272 52272
52272
52272 52272
9 BF Goodrich Company
ao
Center for Environmental Health
ca
ca
5230
Chrysler Corporation
5230 5230 5230
Classic Cars of Ponca City
22
22
81
Du Pont Canada Inc.
14 54-63
Engelhard Corporation
15 41-45
78
Ford Motor Company
6
69-
85
Friction Materials Standards Institute Inc.
2
23
66
87
International Harvester
7 70-71
82
Page No.
II
5,6
13
15 13,14
18 II 7,8 IV 14
11 IV
18 IV
III III 40,41
19 III
IV
15 16-23
16 3-7
IV
8 IV IV
4,5 II
35,36 8-10
9 43-52
IV
CROSS REFERENCES continued
Commenter
Comment NO
Japan Automobile Manufacturers Association
3
38
67
Stratford Citizens Against Pollution
220
220
Monsanto Company
16 46-49
Motor Vehicle Manufacturers Association
.
4 27-28 31-34
37 64-65
80 84 86
Motor Wheel Corporation
ON
ON
Renault USA Inc. Rockwell International
8 mm mm
|
11
73
Wagner Division Edison International Inc.
12 26 30 75-76 88
Page No.
5,6 19,20
37-39
20 III
16 9-11
6 4,5 7-15 17,18 26-34
IV IV 3-7
11 53
9 III
IV
12 54-57
13 3,4
III 59-66
11
|
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