August
1,
2003
1
SIGNIFICANT
NEW
ALTERNATIVES
POLICY
PROGRAM
FOAM­
BLOWING
SECTOR
RISK
SCREEN
ON
THE
USE
OF
ENOVATE
 
3000
(
HFC­
245FA)
AND
HCFC­
22
AS
A
BLOWING
AGENT
FOR
THE
MANUFACTURE
OF
POLYURETHANE
FOAMS.

This
risk
screen
does
not
contain
Clean
Air
Act
(
CAA)
Confidential
Business
Information
(
CBI)
and,
therefore,
may
be
disclosed
to
the
public.

1.
INTRODUCTION
Ozone­
depleting
substances
(
ODS)
are
being
phased
out
of
production
in
response
to
a
series
of
diplomatic
and
legislative
efforts
that
have
taken
place
over
the
past
few
years,
including
the
Montreal
Protocol
and
the
Clean
Air
Act
Amendments
of
1990.
The
U.
S.
Environmental
Protection
Agency
(
EPA),
as
authorized
by
Section
612
of
the
CAA,
has
developed
a
program
to
evaluate
the
human
health
and
environmental
risks
posed
by
alternatives
to
ODS.
The
main
purpose
of
EPA's
program,
called
the
Significant
New
Alternatives
Policy
(
SNAP)
program,
is
to
identify
acceptable
and
unacceptable
substitutes
for
ODS
in
specific
end
uses.
The
results
of
EPA's
screening
assessment
of
potential
human
health
and
environmental
risks
posed
by
substitutes
are
presented
in
the
Background
Document
for
each
sector
(
EPA
1994).
These
documents
are
available
in
EPA's
docket.

EPA's
risk
screen
on
the
use
of
Enovate
 
3000
(
HFC­
245fa)
and
HCFC­
22
as
a
foam
blowing
agent
in
is
summarized
in
this
document.
The
proposed
substitute
is
HFC­
245fa
(
trade
name
Enovate
3000),
mixed
in
different
ratios
with
HCFC­
22
(
see
Table
1).
The
reader
is
referred
to
the
Background
Document
for
the
methodologies
and
assumptions
used
to
conduct
the
risk
screen.

Section
2
of
this
report
summarizes
the
results
of
the
risk
screen
for
the
submitted
blowing
agent,
mixtures
of
HFC­
245fa
and
HCFC­
22.
Section
3
presents
the
toxicity
values
used
for
the
risk
screen;
Section
4
presents
the
results
of
the
atmospheric
assessment;
Sections
5
through
8
discuss
occupational,
consumer,
and
general
population
exposure
and
risk,
respectively;
and
Section
9
discusses
potential
increases
in
atmospheric
releases
of
volatile
organic
compounds
(
VOCs).
August
1,
2003
2
Table
1.
Substitutes
and
Composition
Of
Enovate
 
3000
and
HCFC­
22
Substitute
Composition
Chemical
Name
Chemical
Formula
CAS
No.

Enovate
 
3000
(
HFC­
245fa)
1,1,1,3,3­
pentafluoropropane
C
3
H
3
F
5
460­
73­
1
Enovate
 
3000/
HCFC­
22
HCFC­
22
Chlorodifluoromethane
CHClF
2
75­
45­
6
2.
SUMMARY
OF
RESULTS
Enovate
 
3000
and
HCFC­
22
mixtures
are
recommended
for
SNAP
approval
as
a
foam
blowing
agent.
They
are
not
expected
to
pose
a
threat
to
end
users,
atmospheric
integrity,
or
to
the
health
of
the
general
population.
HCFC­
22
has
a
low
ozone
depletion
potential
(
ODP)
of
less
than
0.1,
while
HFC­
245fa
has
an
ODP
of
zero.
The
GWP
of
the
proposed
substitute
blend
is
lower
than
other
currently
available
and
approved
alternatives.
They
both
pose
low
workplace
flammability
and
explosivity
risks
assuming
good
industrial
hygiene
and
handling
practices
are
used.
The
worker,
consumer,
and
general
exposure
calculations
indicate
no
levels
of
concern.

3.
TOXICITY
REFERENCE
VALUES
FOR
SUBSTITUTES
To
assess
potential
health
risks
from
exposure
to
substitutes
for
ODSs
in
the
foam­
blowing
sector,
EPA
identified
published
values
(
e.
g.,
OSHA
PELs,
or
AIHA
WEELs)
or
developed
Acceptable
Exposure
Limits
(
AELs),
and
reference
concentrations
(
RfCs)
for
the
substitutes.
AELs
were
used
to
assess
risks
to
workers,
and
RfCs
were
used
to
assess
risks
to
the
general
population.
The
AELs
and
RfCs
used
for
this
assessment
are
shown
in
Table
2.
All
are
for
the
inhalation
exposure
route
(
oral
and
dermal
exposures
to
these
substitutes
are
expected
to
be
insignificant).
EPA's
approach
for
identifying
or
developing
these
values
is
discussed
in
detail
in
Chapter
3
of
the
Background
Document.

Acceptable
exposure
limits
include
workplace
guidance
levels
(
WGLs)
and
emergency
guidance
levels
(
EGLs)
for
continuous
and
short­
term
exposure,
respectively.
Whenever
available,
the
WGL
and
EGL
were
based
on
values
developed
by
the
Occupational
Safety
and
Health
Administration,
the
National
Institute
for
Occupational
Safety
and
Health,
the
American
August
1,
2003
3
Conference
of
Governmental
Industrial
Hygienists,
or
the
American
Industrial
Hygiene
Association.
If
values
were
not
available
from
these
sources,
they
were
estimated
by
EPA.

The
preferred
source
of
RfCs
for
ODS
substitutes
was
EPA's
Integrated
Risk
Information
System
(
IRIS),
which
contains
RfCs
that
have
been
verified
by
the
Agency's
Reference
Dose
(
RfD)/
RfC
Work
Group.
If
these
were
unavailable,
EPA
used
(
in
order
of
decreasing
preference)
(
1)
RfCs
that
are
currently
undergoing
verification
by
the
Work
Group,
(
2)
RfCs
that
are
not
yet
undergoing
Work
Group
verification
but
are
contained
in
the
Agency's
Health
Effects
Assessment
Summary
Tables,
(
3)
values
that
were
estimated
based
on
other
types
of
data
for
the
substitute,
or
(
4)
values
estimated
based
on
surrogate
limits.
As
discussed
in
the
Background
Document,
values
that
were
estimated
based
on
other
types
of
data
or
on
surrogates
would
most
likely
not
be
considered
"
verifiable"
by
the
Agency's
RfD/
RfC
Work
Group,
and
were
developed
only
for
the
purpose
of
the
SNAP
risk
screens.

Table
2.
Inhalation
Toxicity
Reference
Values
for
Substitutes
in
the
Foams
Sector
Chemical
OCCUPATIONAL
WGL
(
Long­
term
Exposure)
OCCUPATIONAL
EGL
(
Short­
term
Exposure)
GENERAL
POPULATION
Reference
Concentration
(
RfC)

HFC­
245fa
EPAa
HCFC­
2
1,000
ppm
OSHA
PEL
5,000
ppm
EPAc
14
ppm
a.
Cardiac
sensitization
NOAEL
in
dogs
(
Rusch
et
al.,
1999).
b.
Calculated
using
a
subchronic
NOAEL
of
508
ppm
(
Rusch
et
al.,
1999);
HEC
=
508
x
5
d/
wk/
7
d/
wk
x
6
hr/
d
/
24
hr/
d
=
91
ppm;
91
ppm
/
300
(
UF)
=
0.3
ppm.
Total
UF
of
300
=
10
for
interspecies
extrapolation;
10
for
sensitive
subpopulations
and
3
for
database
limitations,
including
the
absence
of
chronic
and
two­
generation
reproductive
studies.
c.
Estimated.
1
or
0.1
X
the
NOAEL
or
LOAEL
for
cardiotoxicity
Current
information
regarding
the
decomposition
of
the
foam
blowing
agent
[
].

4.
ATMOSPHERICS
MODELING
This
section
presents
an
assessment
of
the
potential
risks
to
atmospheric
integrity
posed
by
the
use
of
Enovate
 
3000
and
HCFC­
22
as
a
foam
blowing
agent.
The
ODP,
GWP,
and
ALT
of
the
proposed
substitutes
are
presented
in
Table
3.

Table
3.
ODPs,
GWPs,
and
ALTs
of
Enovate
 
3000
and
HCFC­
22
August
1,
2003
4
Constituent
ODP
GWP
(
relative
to
CO
2)
100
Year
ALT
HFC­
245fa
0
950
7.2
HCFC­
22
0.055
1700
11.8
Source:
EPA
2002.

The
environmental
impacts
resulting
from
use
of
HFC­
245fa
and
HCFC­
22
are
in
the
range
of
those
predicted
for
other
substitutes
examined
in
the
Background
Document.
The
substitute
is
substantially
less
harmful
to
the
ozone
layer
than
the
continued
use
of
HCFC­
141b.

5.
OCCUPATIONAL
EXPOSURE
AND
HAZARD
ANALYSIS
This
section
presents
estimates
of
potential
occupational
exposures
to
foam­
blowing
agents
during
the
manufacture
of
polyurethane
foams
with
Enovate
 
3000
and
HCFC­
22.
These
estimated
exposures
are
then
compared
to
occupational
exposure
limits
to
determine
whether
they
are
of
potential
concern.

The
methodology
used
for
this
screening
assessment
is
identical
to
the
one
used
in
the
occupational
exposure
and
hazard
analysis
described
in
Chapter
5
of
the
Background
Document.
As
discussed
in
the
Background
Document,
EPA
did
not
identify
any
information
that
specifically
described
employee
exposures
or
current
workplace
conditions
that
affect
exposure
to
foam­
blowing
agents
used
in
the
production
of
polyurethane
foam.
However,
EPA
demonstrated
in
the
Background
Document
that
employee
exposures
to
blowing
agents
for
other
types
of
foam
generally
can
be
maintained
below
the
AELs
of
all
substitutes
when
adequate
ventilation
and
safe
work
practices
are
employed.
Given
the
similarities
of
polyurethane
foams
and
these
other
types
of
foams
in
terms
of
expected
exposure
concentrations,
EPA
believes
that
employee
exposure
to
the
ODS
substitutes
for
polyurethane
foam
blowing
agents
discussed
in
this
report
will
be
maintained
below
their
respective
AELs
as
identified
in
Table
2.

6.
EXPLOSIVITY
AND
FLAMMABILITY
In
Chapter
5
of
the
Background
Document,
EPA
determined
that
the
flammability
and
explosivity
characteristics
of
the
HCFC
examined
in
this
report
do
not
warrant
any
special
precautions,
such
as
the
use
of
permissible
electrical
equipment
or
explosion­
proof
ventilation
systems.
Precautions
to
limit
fire
risk
from
these
materials
include
good
industrial
hygiene
and
handling,
such
as
designing
storage
tanks
and
piping
to
minimize
escape
of
liquid
or
vapor
into
the
workplace,
and
providing
mechanical
ventilation
along
the
manufacturing
process
route.

7.
CONSUMER
EXPOSURE
The
majority
of
the
blowing
agent
used
to
produce
polyurethane
foam
is
released
within
18
to
26
hours
after
manufacturing
and,
thereby,
presents
no
consumer
exposure.
Additionally,
August
1,
2003
5
there
is
a
slow
chemical
release
from
the
product
after
purchase
by
the
consumer.
However,
this
release
of
the
blowing
agent
is
not
expected
to
cause
any
hazard
to
the
consumer
as
the
release
is
minimal.

8.
GENERAL
POPULATION
EXPOSURE
AND
RISK
SCREENING
ANALYSIS
This
section
screens
potential
risks
to
the
general
population
from
exposure
to
ambient
air
releases
of
the
substitutes
examined
in
this
report.
The
methodology
used
for
this
screening
assessment
is
identical
to
the
one
used
in
the
general
population
risk
screen
described
in
Chapter
7
of
the
Background
Document.
The
methodology
and
results
are
summarized
below.

The
general
population
exposure
to
Enovate
 
3000
and
HCFC­
22
resulting
from
the
manufacture
or
use
of
the
substitute
as
a
foam
blowing
agent
is
not
expected
to
cause
any
significant
threats
to
human
health.
The
fenceline
concentration
during
the
processing
of
products
containing
HCFCs
and
HFCs
has
been
determined
for
manufacturing
settings
for
fire
protection
devices
and
refrigerants,
but
not
specifically
for
foam
blowing
applications.
By
analogy
to
the
other
fenceline
analyses
that
have
been
performed,
in
which
exposure
concentrations
were
more
than
two
orders
of
magnitude
below
the
reported
reference
concentrations
(
even
using
conservative
screening
assumptions),
it
is
not
expected
that
foam
blowing
applications
will
pose
health
risks
to
the
general
population.

9.
VOLATILE
ORGANIC
COMPOUND
ANALYSIS
HFCs
and
HCFCs
are
expected
to
pose
negligible
concerns
in
terms
of
their
contribution
to
photochemical
smog.
They
are
not
considered
to
be
volatile
organic
compounds
(
VOCs)
and
are
unreactive
in
the
troposphere.

REFERENCES
EPA
1994.
"
Risk
Screen
on
the
Use
of
Substitutes
for
Class
I
Ozone­
depleting
Substances:
Foam­
Blowing,"
U.
S.
Environmental
Protection
Agency,
March
1994.

EPA
2002.
U.
S.
EPA
Ozone
Depletion.
Available
at:
http://
www.
epa.
gov/
ozone/
August
1,
2003
6
Honeywell.
2003.
Memo
from
Claire
Matlon
to
US
EPA.
27
January
2003.

Rusch,
G.,
Coombs,
D,
and
Hardy,
C.
1999.
The
acute,
genetic,
developmental
and
inhalation
toxicology
of
1,1,1,3,3­
pentafluoropropane
(
HFC
245fa).
Tox.
Sci.
52:
289­
301.
