United States
Environmental Protection
Agency
Risk Reduction Engineeering
Laboratory
Cincinnati, OH 45268
Research and Development
EPA/600/S2-89/049 May 1990
SERA Project Summary
The Selection and
Measurement of Physical
Properties for
Characterization of Chemical
Protective Clothing Materials
Todd R. Carroll and Arthur D. Schwope
Chemical protective clothing
(CPC) must possess certain physical
properties if it is to function as an
effective barrier to chemicals. The
physical characteristics of CPC mat-
erials have gone largely unstudied;
most attention has been focussed on
chemical resistance. Physical prop-
erty tests have been surveyed for
their applicability to CPC materials,
and those tests, which appeared to
be most pertinent, were applied to
ten fabrics and three visor materials.
From statistical analysis of the
results and experience gained in per-
forming the tests, a minimum battery
of tests is recommended. The battery
contains nine primary test methods
that will allow the measurement of
puncture, puncture-propagation tear,
burst, abrasion, accelerated aging,
and electrostatic charge accumula-
tion for CPC fabrics, and abrasion
resistance, deviation in line-of-sight,
and impact for the CPC visor
materials. Further development of a
cut test is recommended before it is
added to the battery.
This Project Summary was
developed by EPA's Risk Reduction
Engineering Laboratory, Cincinnati,
OH, to announce key findings of the
research project that is fully
documented in a separate report of
the same title (see Project Report
ordering information at back).
Introduction
Along with engineering controls and
safe work practices, protective clothing is
an important means for minimizing or
preventing the contact of workers with
potentially harmful chemicals. Such
contacts can occur in settings which
include industrial plants, waste sites, and
uncontrolled spills. Those persons
responsible for worker protection must
have available and specify the most
appropriate clothing for the particular
situation. Chemical Protective Clothing
(CPC) selection, procurement, and
specification require information on the
potential severity of the chemical
contacts, the tasks to be performed, the
skill levels of the workers, the
performance characteristics and
limitations of the protective clothing, and
the effect of the clothing on worker
performance.
Much has been written on the
chemical resistance of protective clothing
materials, and standard test methods
have been promulgated. Of equal or
perhaps greater importance than the
chemical resistance of CPC is that the
clothing remain intact during the work
assignment. The clothing must resist
tears, punctures, cuts, abrasion, and
other physical stresses. Although scores
of standard tests exist for measuring
physical properties of the materials from
which clothing is fabricated, there have
been no studies directed towards
evaluating the applicability of these tests
to CPC. Consequently, there has been no
basis on which to specify either physical
property testing or the minimum
performance in such testing for CPC.
The purpose of this study was to
evaluate published physical property
tests and to recommend a battery of
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tests that could be used in CPC
specification and selection. The study
was directed towards tests for materials
used for garments, in contrast to the
materials used in the fabrication of
gloves, boots, and respirators. Tests were
sought that are applicable over the broad
range of material types, able to
discriminate the performances of different
materials, and relatable to field failure
mechanisms.
Although this study necessarily
produced quantitative physical property
data, no attempt has been made to set
minimum acceptable values for the
results of any of the tests. Minimum
acceptable values are dependent on the
specific application of the clothing. For
example, the physical property
requirements for clothing used in
laboratory applications may be
significantly different from those for
clothing used during entry of confined
spaces that contain unknown chemical
wastes.
The recommended battery of tests
does, however, provide both users and
manufacturers of CPC with a means to
compare and evaluate the performance of
CPC. This battery is preliminary in
nature, as it is used and more data are
generated, the battery will be modified
and expanded. Additionally, use of the
battery and response from the field will
aid in the development of minimum
acceptable performance values.
Procedure
Materials
Ten fabrics used to fabricate pants,
jackets, coveralls, or full body
encapsulating ensembles, and three clear
plastics used to fabricate visors were
used in this study (Table 1). Garments
fabricated from these materials range in
price from less than $10 to over $3000.
Candidate Test Methods
Sources of the standard test methods
used in this study included American
Society for Testing and Materials
(ASTM), Federal Standards, Military
Standards, American National Standards
Institute (ANSI), National Fire Protection
Association (NFPA), and the American
Association of Textile Chemists and
Colorists (AATCC). Approximately 50
methods having potential applicability to
the objectives of this study were
identified, and 14 were selected for
laboratory examination. Brief synopses of
the 14 methods follow:
ASTM F23.20.1-Test Method for
Resistance to Cut (draft 4) — The
specimen is mounted on a holder and
pulled by hand at a nominal rate of 25
cm/min beneath a single-edged,
industrial razor blade which has been
loaded with a known weight. The
minimum weight that produces a cut
completely through the specimen is
recorded. Cut is detected by the
completion of an electrical circuit
between the razor blade and an
aluminum foil placed under the fabric.
NFPA 1973 Gloves for Structural Fire
Fighters (Section 3-2.7)- Puncture
Resistance Testing — A machined, 2.03-
mm diameter stainless steel stylus,
having a tip radius of 25 mm, is pushed
through a specimen at a rate of 127
cm/min. The force required to puncture
the fabric is recorded.
ASTM D1424-Tear Resistance of
Woven Fabrics by Falling-Pendulum
(Elmendorf)" Apparatus — A 12 x 12-mm
notch is cut out of the center of one edge
of a 75 x 75-mm specimen. One side of
the specimen is clamped and the other
side is fixed to a pendulum of known
weight. A 2-cm slit is cut into the center
of the notch and the pendulum is
released causing the specimen to tear.
The tearing force is calculated from the
weight of the pendulum and the distance
that the pendulum travels.
ASTM D2261-Tearing Strength of
Woven Fabrics by the Tongue (Single
Rip) Method (Constant-Rate-of-Extension
Tensile Testing Machine) — A 8.9-cm
long slit is cut length-wise in the center of
a 76 x 203-mm specimen. The fabric on
each side of the slit is fastened into the
jaws (180° opposed) of a tensile testing
machine and the jaws are separated at 5
cm/min. The tear resistance is the force
required to separate the jaws.
ASTM D2582-Puncture- Propagation
Tear Resistance of Plastic Film and Thin
Sheeting- A carriage of known weight
and holding a 0.32-cm diameter, conical
tipped probe is released from a standard
height such that the probe impacts, pun-
ctures, and tears the specimen. The tear
length, carriage weight, and release
height are recorded and used to calculate
the tear resistance.
ASTM D3884-Abrasion Resistance of
Textile Fabrics (Rotary Platform, Double-
Head Method) — This method is also
•Mention of trade names or commercial products
does not constitute endorsement or recom-
mendation for use.
known as the Taber test. The speci
is rotated under two abradant wh
under a specified load. The
parameters are the coarseness of
abradant wheels, the arm weight, anc
number of cycles. In this study, an
weight of 1,000 g was usec
combination with an H22 vitrified wl
Upon completion of the abrasioi
permeation test, ASTM F739,
performed on each abraded specime
determine the effect of abrasion
chemical resistance.
ASTM 04157-Abrasion Resistanc
Textile Fabrics (Oscillatory Cylit
Method) — This method is also know
the Wyzenbeek test. An abradan
secured to a barrel (i.e., the cylinder)
the specimen is secured at a kn
tension in a holder above the cylir
The fabric is lowered onto the oscilU
abradant and held there unde
predetermined load for a predeterm
number of cycles (or double rubs). In
study the tension was 2.3 kg, the loac
kg, and the abradant was #80 grit s;
paper. Similar to the Taber tes
permeation test was used as the endp
test.
ASTM D751-Coated Fabrics, Brea
Strength. Cut Strip Method — A 2
100-mm specimen is clamped in the i
of a tensile testing machine and pi
apart at a rate of 30 cm/min. The fi
required to break the specimen and
elongation at break are measured.
ASTM D751-Coated Fabrics, Burs
Strength — A 2.5-cm diameter spher
pushed at a rate of 30 cm/min throuj
4.5-cm diameter specimen usini
tensile testing machine. The fc
required to break the specimen
measured.
ASTM G26-Operating Light-Expo:
Apparatus (Xenon-Arc Type) with
without Water for Exposure
Nonmetallic Materials — A specime
subjected to periodic exposure
ultraviolet light and rain under condit
of elevated temperatures and humidi
In this study, a four week expos
period was used; the exposure cycle
51 minutes at 90+ %RH and 6l
followed by 9 minutes of rain at 3(
Simultaneously the specimens v\
continuously exposed to a 6000W Xe
Arc lamp operating at 4950W. Specim
were observed for visual changes
tested for changes in breaking strei
and elongation at break as describe'
ASTM 751.
NASA MMA-1985-79-Evaluating Tr
electric Charge Generation and Deca
A 190 x 190-mm specimen is rubbed
a polytetrafluoroethylene (PTFE)
-------
overed wheel rotating at 200 rpm under
1.36 kg load for 10 seconds. The
harge (i.e., voltage) on the specimen is
measured immediately (i.e., the peak
oltage) and 0.5, 1, 2, 3, 4, and 5 sec-
nds thereafter.
ASTM D881-Deviation of Line-of-SigM
- A 150 x 150-mm specimen of a visor
material is held in a position normal to a
le-of-sight established between a fixed
slescope and target. The angular
eviation caused by the visor material is
etermined from the apparent shift of the
rosshairs of the telescope, the distance
etween the specimen and the target,
id the spacing of the lines on the target.
or this investigation, the target consisted
vertical lines spaced 0.25 cm apart
ith the target set 340 cm from the
secimen.
ASTM 01044-Resistance of Trans-
arent Plastics to Surface Abrasion
iaze) — This test is identical to the
iber Abrasion test, however, a finer
Dradant is typically used at fewer
/cles. A CS10 abrading wheel was used
an arm weight of 1,000 grams for 10,
5, and 50 cycles. The loss in light
msmittance at 550 nm was measured.
ASTM D3029-lmpact Resistance of
igid Plastic Sheeting — A 5 x 5-cm
secimen is held in an aluminum clamp
iich has a 3.8-cm diameter hole in it. A
5-gram dart is released from a known
Table 1. Test Materials
height (2.5 cm to 175 cm) and allowjed to
impact the specimen. The mean failure
energy is calculated from the weight of
the dart and height at which 50% cf the
specimens failed. A failure was defined
as visually (unaided) detectable craqks in
the specimen.
Results and Discussion :
The results for all tests, except the
abrasion tests, are summarized in Tables
2 and 3. The content and organization of
Table 2 warrants discussion. Mean values
for each test of each fabric are reported
along with the standard deviation (in
parentheses). The number of replicates,
n, is designated beneath each column
heading. The upper case letter to< the
right of the standard deviation is e;ither
the Duncan's or the Tukey's Groubing
Letter (DGL or TGL, respectively). Vyithin
each test, the letters designate results
that are statistically similar or dissimilar at
the 95% confidence level. For example
under puncture, the result for I the
supported butyl fabric (DGL = A) is
significantly different from that ofi the
supported PVC (DGL = B) but the result
for the supported CPE (OGL = C) is: not
significantly different from that for; the
Viton-Nomex-Chlorobutyl (DGL = Q.I
Table 3 for the visor material^ is
organized in a similar manner with- the
exception that no statistical analysis was
performed.
Cut — Cut resistances of the fabrics
ranged from 365 g to 1265 g. The
method was easy to perform and the
apparatus relatively inexpensive to build.
The draft method, however, has several
shortcomings which must be corrected
before the method can be considered as
part of a standard test battery. These
shortcomings include: lack of a
standardized industrial razor blade, the
absence of a means for controlling the
rate at which the fabric holder is pulled
under the razor blade, the large weight
increments that prevent differentiation of
some fabrics, and the means by which
test results are generated that renders
them difficult to analyze by common
statistical methods. This latter
shortcoming prevented analysis of the
data by Duncan's multiple range test;
thus the DGLs are absent from Table 2.
Questions exist as to the applicability of
the method to all garment materials and
the relationship of the test to field
scenarios.
Puncture — The resistance of the
fabrics to puncture ranged from 3.3 to
19.4 kgf. The puncture test has good
precision; the relative standard deviation
was less than 10% for each fabric.
Whether this test is representative of field
puncture scenarios is open to discussion.
Material
Description
Source
Weight.'
glm2
Thickness,
mm
Fabrics
flirty/ Rubber (supported)
Challenge 5200®
Chemrel®
CPE
CPE (sup
PE-Tyvek®
PVC (supported)
Saranex9- Tyvek
Viton9-Nylon- Chlorobutyl
Viton-Nomex9-Chlorobutyl
Butyl -Nylon Fabric -Butyl
Tefton-Nomex-Teflon
Multilayer Plastic Film-Fabric
Chlorinated Polyethylene
CPE-Polyester Fabric-CPE
Polyethylene-Tvvek
Polyvinyl-Chloride-Polyester
Fabric
Saranex-Tyvek
Viton-Nylon Fabric-Chlorobutyl
Viton-Nomex-Chlorobutyl
Fyrepel Products Inc.
Chemical Fabrics Corp.
Chemron, Inc.
ILC Dover
Standard Safety Equipment Co.
Kappler, Inc.
Standard Safety Equipment
Kappler, Inc.
Life-Guard, Inc.
Fairprene, Inc.
428
528
145
698
743
76
898
126
584
683
0.37
0.26
0.27
0.52
0.60
0.14
0.76
0.19
0.44
0.42
Visor Materials (flat)
FEP (film)
Fluorinated ethylene
propylene copolymer
Chemical Fabrics Corp.
-t
0.25
Polycarbonate
Melamine-coated
Uncoafed
PVC (flexible)
Polyvinyl chloride
General Electric
Sheffield
Standard Safety Equipment Co.
1.02
0.76
1.02
"Average of 5 measurements.
+Average of 20 measurements.
/•A/of measured.
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-------
3uncture is in part determined by the
speed at which an object impacts a fabric
md the freedom that the fabric has to
ilongate upon the impact. These
parameters have not been studied in
lither the laboratory or the field.
fear — This study included the
nvestigation of three tear tests:
Elmendorf, tongue, and puncture-
Kopagation.
Both the Elmendorf and the tongue
jar tests begin with a fabric specimen
mich has been slit. Thus, these tests do
ot measure the resistance of the fabric
3 tear initiation, rather, they measure
nly the resistance to tear propagation.
ince the CPC issued to workers is
resumed free of cuts, tears, holes, and
o forth, these tests may not fully
^present field failure mechanisms.
urthermore, the Elmendorf test yields
nly the maximum value of the tear
isistance for a fabric and the tear
attern exhibited by the nonwoven
jecimens was not consistent with the
iquirements of the method. The types of
'suits produced by the Elmendorf
jparatus varied with the type of fabric
jpport (woven vs. nonwoven) and may
ot be comparable. The values in Table 2
re mean tearing forces.
More representative of a field tear, the
uncture-propagation tear simulates a
edition of snag. The force required to
itiate and propagate a tear is measured.
lis test was applicable to all fabrics and
! precision, as judged by a comparison
relative standard deviations, was
jnsiderably greater than those of the
Imendorf and tongue tear tests.
Abrasion — Several abrasion
rocedures were investigated in an
tempt to identify a method that would
) representative of field conditions. In
is study, ASTM F739 was used to
easure the effect of abrasion on the
temical resistance of the fabric.
cetone was used as the chemical
allenge for all permeation tests. The
ect of abrasion on a material was
dged by the change in breakthrough
le of the acetone.
Abrasion testing is generally
cognized as semi-quantitative in
haracter; reproducibility is difficult to
hieve. The actual abrading action on
he fabric is dependent on the
oarseness of the abradant, the weight
pplied to the abradant, and the number
f abrasion cycles as well as the tautness
f the fabric. Fabric tautness may change
uring the procedure as the fabric heats
id stretches due to the abrasion
•ocess and may vary from fabric to
brie. A general rule of thumb is that the
reproducibility of the abrasion increases
as the number of cycles is increased and
as the coarseness of the abradant is
decreased.
For the Wyzenbeek abrader, the
breakthrough times for acetone and the
Viton-Nylon-Chlorobutyl fabric remained
relatively stable for 25, 50, 75, and 100
cycles, then dropped precipitously at 250
cycles. Even 25 cycles was sufficient to
cause immediate breakthrough of
acetone through the Saranex-Tyvek
material. Breakthrough of acetone
through Challenge 5200 remained above
two hours even after 400 cycles.
Midway through the study
consideration of the Wyzenbeek test was
discontinued in favor of the Taber test for
three reasons. One, the Taber abrasion
pattern is more uniform. Two, the
Wyzenbeek apparatus is no longer
commercially available. Three, the lack of
its commercial availability would seem to
suggest that the Wyzenbeek method has
previously not been found useful by the
textile fabric test community. The Taber
test, on the other hand, is widely
performed and the apparatus is readily
available.
Five hundred Taber cycles caused
immediate breakthrough of acetone
through the Chemrel fabric but had
minimal (if any) effect on the supported
CPE and no apparent effect on the
Challenge 5200.
Abrasion testing with a permeation
endpoint test was successfully used to
discriminate the performances of CPC
fabrics. This study, however, has not
resolved precision shortcomings that are
characteristic of abrasion testing nor have
test conditions (e.g., abradant coarseness
and load) been defined that represent
field scenarios.
Tensile Strength and Elongation at
Break — These common tensile tests
were applied to new fabrics and to fabrics
that had been subject to accelerated
aging. The results are summarized in
Table 2 in a format that has the initial
values on one line and the percent
change in the values due to the aging
immediately underneath. These
measurements are easily performed with
equipment that is commercially available.
Good precision was found and the tests
were applicable to all fabrics.
Static Charge Accumulation — As is
evident from Table 2, the fabrics
exhibited a wide range of abilities to hold
and dissipate voltages produced by
rubbing the fabrics with a PTFE wheel. In
reviewing the data, one must bear in
mind that the absolute value of the
reported result, not its sign, is important.
This characteristic should be considered
when selecting or specifying CPC since
static charges could lead to sparking with
disastrous consequences in certain
situations involving chemicals.
This method is applicable to all types
of CPC materials and appears to enable
discrimination of the results.
Deviation in Une-of-Sight — This test
is designed to measure the deviation in
the line-of-sight caused by a clear plastic.
To be useful, the results must be
obtained with the plastic in its use
configuration; in the case of visors, this
typically means curved. If the deviation in
line-of- sight becomes noticeable, users
of the visor materials will have difficulty
manipulating objects which they are
focusing on.
Table 3 summarizes the limited results
generated during this investigation. Of the
four materials tested, only the PVC
caused any measurable deviation in the
line-of-sight. The method is easy to
perform and appears to be applicable to
all visor materials.
Waze — The Taber test conditions
used in this study were arbitrary but
provide comparative data on the abrasion
resistance of visor materials. Visor
abrasion can occur during suit use,
decontamination and storage.
Table 3 summarizes the measured
decrease in light transmission. The
Melamine-coated polycarbonate retained
the highest amount of light transmission
at 50 cycles. The results show good
precision and it is apparent from the
differences in the results that the method
can discriminate among the performance
of different visor materials.
This test is quick and easy to perform
but requires the use of a spectro-
photometer. The only apparent limitation
to this method is that it can only be used
on flat specimens.
Visor Impact — The test simulates the
impact of a small diameter, semi-sharp
projectile with a visor. Direct relation of
the results to the field, however, is com-
plicated by the fact that the impact during
testing can only occur within the diameter
of the specimen holder. The size of the
holder restricts the potential for deflection
and flexing in the specimen.
Table 3 summarizes the results of the
impact test for the four materials tested.
The FEP was the only material made to
fail by this method. The limitations of our
apparatus were a maximum drop height
of 175 cm and a maximum dart weight of
315 gram.
The test is easy to perform and
applicable to all types of flat visor
materials. Some ambiguity exists in
-------
selecting the correct number of test
specimens. The endpoint of the test is
reached when 50% of the specimens fail.
Statistical Analysis
As discussed above, the results from
each of the fabric tests were subjected to
either a Duncan's or Tukey's analysis in
order to demonstrate the degree to which
the test could be used to discriminate
between the performances of the fabrics.
Another objective of the study was to
identify and eliminate those tests that
seemed to be redundant. A minimum
battery of tests was desired that would
provide broad perspective on the
physical characteristics of protective
clothing materials.
Test method redundancy was
investigated by applying the Spearmen's
Rank Correlation Coefficient (SRCC)
procedure. If the rank orders of the two
lists were exactly the same the coefficient
would be 1, if the rankings were exactly
opposite then the coefficient would be -1.
A coefficient greater than 0.65 is
indicative of a pair of lists in which the
rank orders are in relatively good
agreement.
Strong correlations were found
between the rank orders of the fabrics for
the burst strength/break strength pair
(SRCC = 0.92) and the burst strength/
puncture strength pair (SRCC = 0.84).
Good correlations were found between
the rank orders of the puncture resis-
tance/tongue tear pair (SRCC = 0.70) and
the puncture strength/break strength pair
(SRCC=0.72), and between the tongue
tear/burst strength pair (SRCC = 0.67) and
the tongue tear/break strength pair
(SRCC = 0.65).
Conclusions and
Recommendations
Recommended Test Battery
The standard tests and conditioning
methods listed in Table 4 are recom-
mended as the minimum battery of pro-
cedures for characterizing or specifying
the physical properties of chemical pro-
tective clothing materials. These stan-
dards can be supplemented with others,
dependent on the needs of each specific
application of the clothing.
The puncture-propagation tear test
was selected over the Elmendorf and
tongue tear tests because it appears to
yield unambiguous results for all fabrics
and because it appears to most closely
represent field failure mechanisms for
garment materials.
The burst test is recommended over
the more commonly performed tensile
test because the burst test is easy to
perform and is not subject to the
confounding problems of jaw breaks,
fabric slippage, or fabric orientation.
Furthermore, from the Spearmen's
analysis, the tensile test appears to be
redundant of the burst test.
The Taber abrasion test was selected
over the Wyzenbeek test because of
availability problems of the Wyzenbeek
apparatus and because it can produce
specimens of suitable size and quality for
endpoint testing. The permeation test is
recommended as the endpoint test
assessing the effects of abrasion
chemical resistance. Although i
investigated in this study, the effects
abrasion on the physical integrity of
fabric could be measured by the bi
test.
Accelerated aging followed by
same endpoint tests as for the abra:
test is recommended for those clotf
use scenarios that include a signific
amount of reuse or extensive stor
periods.
The triboelectric charge test has
ticular applicability to work scena
involving flammable or explosive r
erials. Such clothing should also
subject to flammability or flame re
tance testing. Flammability testing
beyond the scope of this study
consequently there is no specific
recommendation herein; other refere
should be consulted.
Although the authors believe a cul
should be part of a minimum test bal
none is included because the pres
available methods have been juc
inadequate. Further work in this ar
recommended. Further work is
recommended pertinent to the abr
test. Finally, efforts should be under
to develop case history files of
failures due to tear, cut, puncture,
and so forth in order to establish a
base for minimum performance spec
tions for each of the tests.
The full report was submits
fulfillment of Contract No. 68-03-32
Arthur D. Little, Inc., under
sponsorship of the U.S. Environn
Protection Agency.
Table 3. Visor Materials Test Results
Material
FEP (film)
Deviation
Thick- of line of '
ness'.cm sight, * ,min
0.025 -T
Haze, % transmission @ 550 nm abrasion cycles
0
89(1 r
(i/3)tt
10
72(3)
(3/3)
25
72(2)
(313)
50
67(2)
(3/3)
Impact
strength, i
1.98 + +
(22)~
Polycarbonate
Melamine-
coated
Uncoated
PVC (flexible)
0.102
0.076
0.102
0
0
3.1
88(1)
(1/3)
88(3)
(1/3)
85(1)
(113)
84(6)
(1f3)
72(2)
(2/3)
73(3)
(313)
33(2)
(1/3)
62(2)
(2/3)
62(3)
(3/3)
73(2)
(1/3)
58(2)
(2/3)
53(4)
(3/3)
>5.43
(10)
>5.43
(10)
>5.43
(10)
ft
Average of 20 measurements.
Maximum deviation measured in three specimens.
Not tested.
Average % transmission (standard deviation).
Average impact strength.
Number of specimens tested/number of measurements made on each specimen tested.
Number of specimens tested.
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Table 4. Recommended Physical Property Test Methods For Chemical
Protective Clothing
Fabrics
Puncture resistance
Puncture-propagation tear
resistance
Abrasion resistance endpoint tests:
Bursting resistance
Accelerated aging endpoint tests:
Electrostatic charge
Visor Materials
Deviation in line-of-sight
Haze-abrasion resistance
Impact resistance
NFPA 1973- Paragraph 3-2.7
ASTM 02582
ASTM 03884
Permeation-ASTM F739
Burst Strength-ASTM D 751
ASTM 751
ASTM G26
Permeation-ASTM F739
Burst Strength- ASTM 0751
NASA MMA-1985-79
ASTM 0881
ASTM 01044
ASTM 03029
-------
Todd R. Carroll and Arthur D. Schwope are with Arthur D. Little, Inc., Cambridge,
MA 02140-2390
Michael D. Royer is the EPA Project Officer (see below).
The complete report, entitled "The Selection and Measurement of Physical
Properties for Characterization of Chemical Protective Clothing Materials,"
(Order No. PB90-188-731/AS; Cost: $17.00 subject to change) will be
available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Superfund Technology Demonstration Division
Risk Reduction Engineering Laboratory
Edison, New Jersey 08837-3679
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
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