United States
Environmental Protection
Agency
Hazardous Waste Engineering
Research Laboratory
Cincinnati OH 45268
Research and Development
EPA/600/S2-85/084 Dec. 1985
Project Summary
Evaluation of the Resistance
of a Chlorinated Polyethylene
Protective Garment Material to
Permeation and Degradation
by Liquid Chemicals
John Meade, William Ellis, and Judy Ludington
The objectives of this project were to
investigate existing permeation and
degradation resistance data for chlori-
nated polyethylene (CPE); to develop a
laboratory test plan consistent with
American Society for Testing and Mate-
rials (ASTM) Standard Test Methods
F739-81 and D471-79 regarding perme-
ation, solubility, swelling, and degrada-
tion of CPE fabric by test chemicals;
and to obtain laboratory test data for
chemical and CPE combinations of in-
terest for which only limited or ques-
tionable permeation and degradation
resistance data exist. Ten liquid chemi-
cals (acetic acid, acetic anhydride, ace-
tone, bis(2-chloroethyl)ether, carbon
tetrachloride, ethylene diamine, iso-
propyl alcohol, N-nitrosodimethy-
lamine, phenol, and o-xylene) were
tested to determine permeation rates,
breakthrough times, and swelling
when contacted with 20 mil thick CPE.
Mean permeation breakthrough times
ranged from 15 minutes to over
8 hours. Steady-state permeation rates
ranged from 0 to 170 mg • m~2 • sec"1.
Solubility and swelling data also
showed wide variation depending
upon the chemical. Soaking the CPE in
one chemical resulted in a loss of
weight, while contact with four other
compounds resulted in weight gains by
the CPE test swatch of over 100%.
Chemical contact was also shown in 8
of 10 cases to reduce the capacity of
the CPE for resisting tearing due to
deformation.
This Project Summary was devel-
oped by EPA's Hazardous Waste Engi-
neering Research Laboratory, Cincin-
nati, OH, to announce key findings of
the research project that is fully docu-
mented in a separate report of the same
title (see Project Report ordering infor-
mation at back).
Introduction
Project Objectives/Approach/
Organization
The objectives of this project were to
evaluate the permeation and degrada-
tion resistance of a 20 mil chlorinated
polyethylene (CPE) chemical protective
outer garment material when contacted
by hazardous and toxic substances to
which chemical spill and uncontrolled
hazardous waste site response person-
nel may be exposed. To reach this ob-
jective, JRB Associates identified and
evaluated the existing permeation and
degradation data base as of August
1983; proposed a prioritized list of
untested substances; and developed a
preliminary laboratory permeation/
degradation resistance test plan, which
was based primarily on ASTM Method
D-471-79, "Standard Test Method for
Rubber Property—Effects of Liquids"
and ASTM F-739-81. "Standard Test
Method for Resistance of Protective
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Clothing Materials to Permeation by
Hazardous Liquid Chemicals"; and
managed the execution of this test plan
by Rocky Mountain Analytical Laborato-
ries (RMAL). An external audit of the
permeation testing was conducted by IT
Corporation-EERU. As part of the exter-
nal audit, duplicate samples were sub-
jected to permeation testing by Radian
Corporation.
Rationale for Evaluating the
Performance of 20 mil CPE
The U.S. Environmental Protection
Agency (EPA), pursuant to the Compre-
hensive Environmental Response, Com-
pensation, and Liability Act of 1980
(CERCLA), participates in response, in-
vestigation, mitigation, control, and
cleanup of hazardous substance spills
and uncontrolled hazardous waste
sites. When conditions require it, EPA
personnel utilize totally encapsulating
ensembles to provide protection from
dermal and respiratory contact with
hazardous substances. Based on their
field experiences with totally encapsu-
lating ensembles, EPA personnel ex-
pressed a need in 1981 for an ensemble
with a self-contained, long-term air sup-
ply; breathing air and body cooling; and
total body protection from chemical
splashes or vapors and from pinholes or
leaking seals in the protective outer gar-
ment. The U.S. Army's Chemical Sys-
tems Laboratory (since re-named the
Chemical Research and Development
Center) and the U.S. Coast Guard had
developed a prototype ensemble that
potentially met EPA's requirements.
The EPA entered into an Interagency
Agreement with the U.S. Army in 1982
to advance the development of the pro-
totype ensemble, named the Long-
term, Self-contained, Chemical Protec-
tive Ensemble (LSCPE).
The current LSCPE outer garment
consists primarily of 20 mil chlorinated
polyethylene (CPE), which had previ-
ously been selected by the Army after
extensive evaluation and testing fo'r use
in its Demilitarization Protective Ensem-
ble. However, the outer garment only
required that penetration testing be
conducted with "(chemical warfare)
agents, decontaminants, hydraulic flu-
ids, and other liquid substances present
in the toxic area and liable to come into
contact with the ensemble."1 For EPA's
'The Demilitarization Protective Ensemble, Volume
I—The Development Program, An Overview. U.S.
Army Chemical Systems Laboratory, 1982, p. 24.
intended use of the LSCPE, additional
data were required on the degradation
and permeation resistance of CPE when
in contact with chemical substances
that EPA personnel were likely to en-
counter at chemical spills and uncon-
trolled hazardous waste sites.
Materials and Methods
CPE Test Samples and the Ten
Challenge Chemicals
Test samples of CPE were provided
by ILC Dover. The sample, material was
designated as 20 mil Cloropel™ alloyed
CPE (ILC part number ST92C019-03,
lot 2). All swatches were smooth, with-
out seams.
The selection of the challenge chemi-
cals to be tested was based primarily
upon a literature search designed to
identify the chemicals most commonly
found in hazardous chemical spills and
at hazardous waste disposal sites. The
list of challenge chemicals selected
originally numbered 50, and tests were
performed on 10 of those compounds.
The 10 chemicals used to test CPE were
acetic acid, acetic anhydride, acetone,
bis-(2-chloroethyl) ether, carbon tetra-
chloride, ethylenediamine, isopropanol,
N-nitrosodimethylamine, phenol, and
ortho-xylene.
Methodology for Determining
Breakthrough Times and Per-
meation Rates
Breakthrough times and permeation
rate measurements were performed
with minor variations according to the
American Society for Testing and Mate-
rials (ASTM) Standard Test Method for
Resistance of Protective Clothing Mate-
rials to Permeation by Hazardous Liquid
Chemicals (F739-81). This method re-
quires that the protective material be
clamped into a test cell and then be sub-
jected to chemical contact on one side
and a collecting medium on the other
side. The collecting medium is sampled
over time to determine whether any of
the test chemical has permeated the
membrane. The principal data gener-
ated are the breakthrough time and the
steady-state permeation rate of the
chemical through the polymer mem-
brane. Breakthrough time is the
"elapsed time between initial contact of
the hazardous liquid chemical with the
outside surface of a protective clothing
material and the time at which the
chemical can be detected at the inside
surface of the material by means of the
chosen analytical technique." Steady-
state permeation is "the constant rate of
permeation that occurs after break-
through when all forces affecting per-
meation have reached equilibrium."2
Methodology for Measuring
the Solubility and Swelling of
CPE Caused by Immersion in
Liquid Test Chemicals
ASTM Standard Method D471-79
(Rubber Property—Effect of Liquids)
was used to determine the solubility
and swelling of the CPE material after
immersion into the 10 test chemicals.
The general procedure used was as
follows. Triplicate CPE swatches for
each test chemical were cut into approx-
imately 25 mm x 50 mm rectangles.
The mass, length, width, and thickness
of the swatches were then determined
before immersion into the test chemi-
cal. After immersion into the test chem-
ical, the swatches were removed at in-
tervals of approximately 5 min, 15 min,
30 min, 60 min, 3 hours and 24 hours
and the above measurements were per-
formed again. The tests were continued
until saturation was achieved or until a
24 hour immersion period had oc-
curred. Saturation was defined as hav-
ing been achieved if successive mass
measurements differed by less than 2%.
The percent change in mass due to
saturation or immersion in the test
chemical for 24 hours was determined
using the following formula:
AM (%) = (M2 - Mi)/M, x 100%
where:
AM = percent mass change
MI = mass of the CPE swatch after sat-
uration with the test chemical or
immersion in the test chemical
for 24 hours, whichever came first
M2 = Initial mass of the CPE swatch
prior to the first immersion in the
test chemical
Analogous formulas were used to cal-
culate the percent length, width and
thickness changes due to chemical
saturation.
Methodology for Measuring
the Degradation of CPE Follow-
ing Immersion In Liquid
Chemicals
A non-standard test was performed to
measure the degradation of chemical-
soaked CPE when subjected to repeated
physical deformation. Three CPE
^Definitions are from the ASTM Method F-739-81.
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Table 1. Breakthrough
Chemical
Acetic Acid
Acetic Anhydride
Acetone
Bis-(2 Chloroethyl) ether
Carbon Tetrachloride
Ethylenediamine
Isopropanol
N-Nitrosodimethylamine
Phenol
O-Xylene
Times of Test Chemicals
RMAL
Breakthrough Time
(min)
Raw Mean
265
241
205
86
76
64
16
18
18
99
56
61
245
199
183
128
131
101
N/A
38
32
21
184
224
77
72
67
237
75
77
72
209
120
<1
30
204
72
Through 20 mil
R.S.D
%
72.7
74.6
6.7
32.7
15.4
13.3
N/A
28.4
13.5
6.9
CPE
Radian
Breakthrough Time R.S.D.
(min) %
Raw Mean
140
146
147
72
72
72
15
15
15
91
83
87
205
210
207
154
159
167
>480
>480
>480
42
42
42
165
180
180
62
66
60
144 2.6
72 0
15 0
87 4.6
207 1.2
160 4.1
>480 N/A
42 0
175 5.0
63 4.9
RMAL and Radian
Mean Breakthrough
Time
(min)
191
74
16
80
208
140
N/A
36
187
67
R.S.D.
%
28.5
9.8
9.1
21.6
9.8
17.3
N/A
23.2
11.8
9.3
swatches per chemical were immersed
into the liquid test chemicals using the
same procedures as those described
previously. Every swatch was then sub-
jected to prodding to a depth of 0.5
inches by a blunt steel rod at a rate of
10 ±2 times per minute. Every two
hours, the swatch was inspected and
observed for changes in color, surface
smoothness or shape with respect to a
control swatch which had not been sat-
urated with the test chemical but had
been subjected to the same repeated
prodding.
The apparatus used to subject the
CPE swatches to deformation consisted
of an electrically driven motor con-
nected to a series of belts and pulleys.
The pulleys were chosen to produce the
desired rate of prodding and to allow
the blunt rod to prod the swatch to a
depth of 0.5 inches (13 mm): After a
swatch was saturated with the test
chemical, it was held perpendicular to
the prodding rod with a 1 inch brass
union.
Results and Discussion
Breakthrough Times and Per-
meation Rates of Test Chemi-
cals Through CPE
Breakthrough times and steady-state
permeation rates for the 10 test chemi-
cals passing through the CPE test
swatches are listed in Tables 1 and 2.
Mean breakthrough times from both
laboratories are in relatively close
agreement between 8 of the 10 pairs of
data. There was a major difference be-
tween the mean breakthrough times for
acetic acid (237 min vs. 144 min). No
explanation for the discrepancy was
found, but both mean breakthrough
times represent significant resistance to
permeation. There was also a major dif-
ference (<1 min vs. >480 min) between
the individual laboratory mean break-
through times for isopropanol. The low
(<1 min) values were discarded in the
evaluation of CPE performance, be-
cause (a) the resistance of CPE to an-
other alcohol (methanol) was found
from other data to be much greater than
one minute, (b) CPE did not show signs
of degradation as a result of contact
with isopropanol, and (c) similar very
short breakthrough times for carbon tet-
rachloride were generated and dis-
carded, since good precision both
within and between laboratories was
demonstrated for high breakthrough
times that were generated for the car-
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bon tetrachloride. It is assumed that the
cause of the low breakthrough times for
isopropanol are the same as for the car-
bon tetrachloride.
In the case of carbon tetrachloride,
breakthrough times from one lab fell
into two distinct groups, <1 minute and
183-245 minutes. The second labora-
tory's data were in the 205-210 minute
range. The low breakthrough times
were discarded due to the close agree-
ment on the high values between two
independent laboratories.
External Quality Assurance
Program for Permeation Tests
An external quality assurance audit of
the permeation testing was conducted.
The purpose of the program was to en-
sure an acceptable degree of confi-
dence in the data generated during the
permeation testing of the 20 mil CPE
outer garment material. This was ac-
complished through the use of perfor-
mance evaluation samples, inter-labora-
tory testing, and review of analytical
protocols, internal quality control pro-
cedures, data, and analysis results.
Solubility and Swelling of
Chlorinated Polyethylene
Caused by Immersion In the
Test Chemicals
Average percent increases in mass
after saturation or immersion in the test
chemical for 24 hours ranged from 0.5%
for ethylenediamine to 126% for
bis(2-chlorethyl ether). Test chemicals
that caused percent mass increases of
less than 100% of the original CPE
swatch weight were ethylenediamine
(0.5%), isopropanol (3.5%), acetic acid
(29%), phenol (34%) and acetone
(57.3%). Test chemicals that caused
mass increases exceeding 100% of
the original CPE swatch weight
were carbon tetrachloride (100%),
N-nitrosodimethylene (112%), o-xylene
(112%) and bis(2-chloroethyl) ether
(126%).
Performance of Chemical-
Soaked CPE when Subjected to
Repeated Physical Deformation
CPE swatches not exposed to any
chemical formed shallow indentations
but essentially recovered their initial
shape after the test was terminated.
Chemicals that did not cause any of
the triplicate trial swatches to tear dur-
ing the two-hour deformation test
period were acetic anhydride, carbon
tetrachloride, and isopropanol. Chemi-
Table 2. Permeation Rates of Test Chemicals Through 20 mil CPE
Radian
R.S.D.
Raw Mean
Acetic Acid
Acetic Anhydride
Acetone
Bis-(2-Chloroethyl) ether
Carbon Tetrachloride
Eth ylenediamine
Isopropanol
N-Nitrosodimethylamine
Phenol
O-Xylene
10
10 7
2
10
7 9
9
169
146 170
194
154
45 80
40
15
14 13
10
2
7 6
10
0
0 0
0
55
84 73
81
9
11 10
10
32
29 31
31
65.7
16.7
14.1
80.0
20.4
63.8
N/A
21.7
10.0
5.0
cats that caused only one of the three
test swatches to tear during the two
hour deformation test were acetic acid,
acetone and ethylenediamine. And
chemicals that caused more than one of
the three trial swatches to tear during
the two hour deformation test
were bis(2-chloroethyl) ether,
N-nitrosodimethylamine, phenol, and
o-xylene.
Comparison of 20 MIL CPE Test
Results and Potential Opera-
tional Requirements for LSCPE
Users
In this section, the performance of 20
mil CPE, as measured by the tests con-
ducted in this project, will be compared
to a limited number of potential opera-
tional requirements that may confront
the wearer of the LSCPE. The discussion
in this section should not be taken as a
firm recommendation for or against the
use of 20 mil CPE in any specific situa-
tion. Determination of acceptability for
specific situations should include the
consideration by a qualified person of
factors not addressed in the report, for
example, temperature; probability of
exposure; toxicity; type of exposure
(immersion, splash, mist, vapor, etc.);
surface area exposed; length of expo-
sure; time available to escape, decon-
taminate, and doff the outer garment;
other materials of construction of the
garment.
As described in the introduction, the
performance of 20 mil CPE was evalu-
ated because this polymer comprises
the primary outer garment material of a
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prototype ensemble undergoing ad-
vanced development in an EPA/Army
project. The ensemble has a self-
contained breathing supply with a dura-
tion of 2.5 hours; thus, at worst, the
ensemble outer garment may be re-
quired to withstand 2.5 hours of chemi-
cal contact without degrading or be-
coming permeated.
With this 2.5 hour service life in mind,
the performance of CPE was examined
in two areas, one of which was Perme-
ation Breakthrough Resistance. In this
area, each CPE-chemical pair was
placed in one of four categories based
upon the breakthrough times observed
in the permeation tests conducted in
this project. The second performance
area was Tearing/Deformation Resis-
tance. In this area, each CPE-chemical
pair was placed in one of two categories
based upon the results obtained from
the test in which CPE swatches were
soaked in the test chemical and then re-
peatedly prodded with a blunt steel rod
for up to two hours, as described in the
procedures section.
Conclusions
The Long-term, Self-contained,
Chemical Protective Ensemble (LSCPE),
which has an outer garment con-
structed primarily of 20 mil CPE, has a
self contained breathing air supply of
2.5 hours (150 minutes). Thus, to be
fully satisfactory, the CPE must resist
permeation by the test chemical for
150 minutes or more. Secondly, chemi-
cal contact should not seriously de-
grade the tearing resistance of the CPE
after repeated prodding with a blunt
steel rod.
• CPE (20 mil thick) demonstrated high
resistance to both permeation and
tearing when contacted by carbon tet-
rachloride and isopropanol. Four of
the compounds that were tested, [iso-
propanol (> 480 min*), carbon tetra-
chloride (207 min*), phenol (175 min),
and ethylenediamine (160 min)] had
mean breakthrough times exceeding
150 minutes, and acetic acid (144 min)
nearly met the 150 minute criterion.
However, of the five compounds cited
immediately above, only isopropanol
and carbon tetrachloride did not de-
grade the ability of CPE to resist tear-
ing after being subjected to repeated
deformation. Phenol exposure caused
serious loss of tearing resistance—
each of three CPE samples stiffened
and tore after repeated deformation.
A less severe reduction in tearing re-
sistance was caused following expo-
sure to ethylenediamine and acetic
acid.
• One compound, acetone, had a mean
breakthrough time (15 min) that
would pose problems for an LSCPE
wearer, who would probably have to
exit a contaminated work area and un-
dergo decontamination before doffing
the outer garmet.
• The mean permeation breakthrough
times (42 to 87 minutes) for the remain-
ing compounds [N-nitrosodimethy-
lamine, o-xylene, acetic anhydride, and
bis(2-chloroethyl) ether] indicate that
moderate protection from permeation
is provided. However, only acetic anhy-
dride did not degrade the tearing resis-
tance of CPE. N-nitrosodimethylamine,
o-xylene, and bis(2-chloroethyl) ether
caused each chemical-soaked CPE sam-
ple (three samples per chemical) to tear
when subjected to repeated prodding
with a blunt steel rod.
•Breakthrough times of <1 minute were also noted
for isopropanol and carbon tetrachloride. Based
on data for similar compounds and for the same
compounds tested by different laboratories, it is
likely that these very low breakthrough times are
due to material imperfections or experimental
error, although this has not been conclusively
demonstrated.
•&U. S. GOVERNMENT PRINTING OfTICE:1986/646-l 16/20734
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JohnMeade, William Ellis, and Judy Ludington are with JRB Associates/Science
Applications International Corporation. McLean, VA 22102.
Michael Royer is the EPA Project Officer (see below).
The complete report, entitled "Evaluation of the Resistance of a Chlorinated
Polyethylene Protective Garment Material to Permeation and Degradation by
Liquid Chemicals," (Order No. PB 85-242 337; Cost: $11.95, 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:
Hazardous Waste Engineering Research Laboratory
U.S. Environmental Protection Agency
Cincinnati, OH 45268
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
ID
Official Business
Penalty for Private Use $300
EPA/600/S2-85/084
0000329 PS
U S SNVIR PROTECTION AGENCY
REGION 5 LieftAftY
230 3 OEftRBORN STR€ŁT
CHICAGO IL 6060*
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