Proposed Rule2024-25971
Air Quality: Revision to the Regulatory Definition of Volatile Organic Compounds-Exclusion of (Z)-1-chloro-2,3,3,3-tetrafluoropropene (HCFO-1224yd(Z))
Primary source
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Published
November 12, 2024
Issuing agencies
Environmental Protection Agency
Abstract
The U.S. Environmental Protection Agency (EPA) is proposing to revise the EPA's regulatory definition of volatile organic compounds (VOC) under the Clean Air Act (CAA). This action proposes to add (Z)-1- chloro-2,3,3,3-tetrafluoropropene (also known as HCFO-1224yd(Z); CAS number 111512-60-8) to the list of compounds excluded from the regulatory definition on the basis that this compound makes a negligible contribution to tropospheric ozone (O<INF>3</INF>) formation.
Full Text
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<title>Federal Register, Volume 89 Issue 218 (Tuesday, November 12, 2024)</title>
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[Federal Register Volume 89, Number 218 (Tuesday, November 12, 2024)]
[Proposed Rules]
[Pages 88940-88947]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2024-25971]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 51
[EPA-HQ-OAR-2023-0295; FRL-10823-01-OAR]
RIN 2060-AW00
Air Quality: Revision to the Regulatory Definition of Volatile
Organic Compounds--Exclusion of (Z)-1-chloro-2,3,3,3-tetrafluoropropene
(HCFO-1224yd(Z))
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.
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SUMMARY: The U.S. Environmental Protection Agency (EPA) is proposing to
revise the EPA's regulatory definition of volatile organic compounds
(VOC) under the Clean Air Act (CAA). This action proposes to add (Z)-1-
chloro-2,3,3,3-tetrafluoropropene (also known as HCFO-1224yd(Z); CAS
number 111512-60-8) to the list of compounds excluded from the
regulatory definition on the basis that this compound makes a
negligible contribution to tropospheric ozone (O<INF>3</INF>)
formation.
DATES: Comments must be received on or before January 13, 2025.
ADDRESSES: You may send comments, identified by Docket ID No. EPA-HQ-
OAR-2023-0295, by any of the following methods:
<bullet> Federal eRulemaking Portal: <a href="https://www.regulations.gov/">https://www.regulations.gov/</a>
(our preferred method). Follow the online instructions for submitting
comments.
<bullet> Mail: U.S. Environmental Protection Agency, EPA Docket
Center, Docket No. EPA-HQ-OAR-2023-0295, Office of Air and Radiation
Docket, Mail Code 28221T, 1200 Pennsylvania Avenue NW, Washington, DC
20460.
<bullet> Hand Delivery or Courier: EPA Docket Center, WJC West
Building, Room 3334, 1301 Constitution Avenue NW, Washington, DC 20004.
The Docket Center's hours of operations are 8:30 a.m.-4:30 p.m.,
Monday-Friday (except Federal Holidays).
Instructions: All submissions received must include the Docket ID
No. for this
[[Page 88941]]
rulemaking. Comments received may be posted without change to <a href="https://www.regulations.gov/">https://www.regulations.gov/</a>, including any personal information provided. For
detailed instructions on sending comments and additional information on
the rulemaking process, see the ``Public Participation'' heading of the
SUPPLEMENTARY INFORMATION section of this document.
FOR FURTHER INFORMATION CONTACT: Dr. Souad Benromdhane, Office of Air
Quality Planning and Standards, Health and Environmental Impacts
Division, Mail Code C539-07, Environmental Protection Agency, P.O. Box
12055, Research Triangle Park, NC 27711; telephone: (919) 541-4359;
email address: <a href="/cdn-cgi/l/email-protection#3250575c405d5f565a535c571c415d475356725742531c555d44"><span class="__cf_email__" data-cfemail="c0a2a5aeb2afada4a8a1aea5eeb3afb5a1a480a5b0a1eea7afb6">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Public Participation
Written comments: Submit your comments, identified by Docket ID No.
EPA-HQ-OAR-2023-0295, at <a href="https://www.regulations.gov">https://www.regulations.gov</a> (our preferred
method), or the other methods identified in the ADDRESSES section. Once
submitted, comments cannot be edited or removed from the docket. The
EPA may publish any comment received to its public docket. Do not
submit to EPA's docket at <a href="https://www.regulations.gov">https://www.regulations.gov</a> any information
you consider to be Confidential Business Information (CBI), Proprietary
Business Information (PBI), or other information whose disclosure is
restricted by statute. Multimedia submissions (audio, video, etc.) must
be accompanied by a written comment. The written comment is considered
the official comment and should include discussion of all points you
wish to make. The EPA will generally not consider comments or comment
contents located outside of the primary submission (i.e., on the web,
cloud, or other file sharing system). Please visit <a href="https://www.epa.gov/dockets/commenting-epa-dockets">https://www.epa.gov/dockets/commenting-epa-dockets</a> for additional submission methods; the
full EPA public comment policy; information about CBI, PBI, or
multimedia submissions; and general guidance on making effective
comments.
Table of Contents
I. Does this action apply to me?
II. Background
A. The EPA's VOC Exemption Policy
B. Petition To List HCFO-1224yd(Z) as an Exempt Compound
III. The EPA's Assessment of the Petition
A. Contribution to Tropospheric Ozone Formation
B. Potential Impacts on Other Environmental Endpoints
1. Contribution to Stratospheric Ozone Depletion
2. Toxicity
3. Contribution to Climate Change
C. Conclusions
IV. Proposed Action
V. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review and
Executive Order 14094: Modernizing Regulatory Review
B. Paperwork Reduction Act (PRA)
C. Regulatory Flexibility Act (RFA)
D. Unfunded Mandates Reform Act (UMRA)
E. Executive Order 13132: Federalism
F. Executive Order 13175: Consultation and Coordination With
Indian Tribal Governments
G. Executive Order 13045: Protection of Children From
Environmental Health and Safety Risks
H. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution or Use
I. National Technology Transfer and Advancement Act (NTTAA)
J. Executie Order 12898: Federal Actions To Address
Environmental Justice in Minority Populations and Low-Income
Populations and Executive Order 14096: Revitalizing Our Nation's
Commitment to Environmental Justice for All
VI. References
I. Does this action apply to me?
Entities potentially affected by this proposed rule include, but
are not necessarily limited to, the following: State and local air
pollution control agencies that adopt and implement regulations to
control air emissions of VOC; and industries manufacturing and/or using
HCFO-1224yd(Z) for use in foam blowing, refrigeration, as well as
applications in solvents and aerosol propellants, and other minor uses.
Potential entities that may be affected by this action include the
following:
Table 1--Potentially Affected Entities by North American Industrial Classification System (NAICS) Code
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Category NAICS code Description of regulated entities
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Industry............................. 333415 Air-Conditioning and Warm Air Heating Equipment and
Commercial and Industrial Refrigeration Equipment
Manufacturing.
Industry............................. 811310 Commercial and industrial machinery and equipment (except
automotive and electronic) repair and maintenance.
Industry............................. 221116 Geothermal Electric Power Generation.
Industry............................. 221117 Biomass Electric Power Generation.
Industry............................. 221118 Other Electric Power Generation.
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This table is not intended to be exhaustive but rather provides a
guide for readers regarding entities that might be affected by this
deregulatory action. This table lists the types of entities that the
EPA is now aware of that could potentially be affected to some extent
by this action. Other types of entities not listed in the table could
also be affected to some extent. To determine whether your entity is
directly or indirectly affected by this action, you should consult your
State or local air pollution control and/or air quality management
agencies.
II. Background
A. The EPA's VOC Exemption Policy
Tropospheric O<INF>3</INF>, commonly known as smog, is formed when
VOC and nitrogen oxides (NO<INF>X</INF>) react in the atmosphere in the
presence of sunlight. Because of the harmful health effects of
O<INF>3</INF>, the EPA and State governments limit the amount of VOC
that can be released into the atmosphere. VOC form O<INF>3</INF>
through atmospheric photochemical reactions, and different VOC have
different levels of reactivity. That is, different VOC do not react to
form O<INF>3</INF> at the same speed or form different amounts of
O<INF>3</INF>. Some VOC react more slowly or form less O<INF>3</INF>;
therefore, changes in their emissions have limited effects on local or
regional O<INF>3</INF> pollution episodes. It has been the EPA's policy
since 1971 that certain organic compounds with a negligible level of
reactivity should be excluded from the regulatory definition of VOC to
focus VOC control efforts on compounds that significantly affect
O<INF>3</INF> concentrations. The EPA also believes that exempting such
compounds creates an incentive for industry to use negligibly reactive
compounds in place of more highly reactive compounds that are regulated
as VOC. The EPA lists compounds that
[[Page 88942]]
it has determined to be negligibly reactive in its regulations as being
excluded from the regulatory definition of VOC (40 CFR 51.100(s)).
The CAA requires the regulation of VOC for various purposes.
Section 302(s) of the CAA specifies that the EPA has the authority to
define the meaning of ``VOC'' and, hence, what compounds shall be
treated as VOC for regulatory purposes. The policy of excluding
negligibly reactive compounds from the regulatory definition of VOC was
first laid out in the ``Recommended Policy on Control of Volatile
Organic Compounds'' (42 FR 35314, July 8, 1977) (``1977 Recommended
Policy'') and was supplemented subsequently with the ``Interim Guidance
on Control of Volatile Organic Compounds in Ozone State Implementation
Plans'' (70 FR 54046, September 13, 2005) (``2005 Interim Guidance'').
The EPA uses the reactivity of ethane as the threshold for determining
whether a compound has negligible reactivity. Compounds that are less
reactive than, or equally reactive to, ethane under certain assumed
conditions may be deemed negligibly reactive and, therefore, suitable
for exemption from the regulatory definition of VOC. Compounds that are
more reactive than ethane continue to be considered VOC for regulatory
purposes and, therefore, are subject to control requirements. The
selection of ethane as the threshold compound was based on a series of
smog chamber experiments that underlay the 1977 Recommended Policy.
The EPA has used three different metrics to compare the reactivity
of a specific compound to that of ethane: (i) the rate constant for
reaction with the hydroxyl radical (OH) (known as k<INF>OH</INF>); (ii)
the maximum incremental reactivity (MIR) on a reactivity per unit mass
basis; and (iii) the MIR expressed on a reactivity per mole basis.
Differences between these three metrics are discussed below.
The k<INF>OH</INF> is the rate constant of the reaction of the
compound with the OH radical in the air. This reaction is often, but
not always, the first and rate-limiting step in a series of chemical
reactions by which a compound breaks down in the air and contributes to
O<INF>3</INF> formation. If this step is slow, the compound will likely
not form O<INF>3</INF> at a very fast rate. The k<INF>OH</INF> values
have long been used by the EPA as metrics of photochemical reactivity
and O<INF>3</INF>-forming activity, and they were the basis for most of
the EPA's early exemptions of negligibly reactive compounds from the
regulatory definition of VOC. The k<INF>OH</INF> metric is inherently a
molar-based comparison, i.e., it measures the rate at which molecules
react.
The MIR, both by mole and by mass, is a more updated metric of
photochemical reactivity derived from a computer-based photochemical
model, and it has been used as a metric of reactivity since 1995. This
metric considers the complete O<INF>3</INF>-forming activity of a
compound over multiple hours and through multiple reaction pathways,
not merely the first reaction step with OH. Further explanation of the
MIR metric can be found in Carter (1994).
The EPA has considered the choice between MIRs with a molar or mass
basis for the comparison to ethane in past rulemakings and guidance. In
the 2005 Interim Guidance, the EPA stated that a comparison to ethane's
MIR on the mass basis strikes the right balance between a threshold
that is low enough to capture chemicals that significantly affect ozone
formation and a threshold that is high enough to allow for the
exemption of some other chemicals that may usefully substitute for more
reactive compounds. The guidance also stated that EPA will continue to
compare chemicals to ethane using k<INF>OH</INF> expressed on a molar
basis and MIR values expressed on a mass basis during the review of
suggested chemicals for VOC-exempt status.\1\ The 2005 Interim Guidance
notes that the EPA will consider a compound to be negligibly reactive
if it is equally reactive as or less reactive than ethane based on
either k<INF>OH</INF> expressed on a molar basis or MIR values
expressed on a mass basis (70 FR 54046).
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\1\ Interim Guidance on Control of Volatile Organic Compounds in
Ozone State Implementation Plans, 2005, US Environmental Protection
Agency, Document Number 05-18015 (70 FR 54046). And could be found
at this link: <a href="https://www.govinfo.gov/content/pkg/FR-2005-09-13/pdf/05-18015.pdf">https://www.govinfo.gov/content/pkg/FR-2005-09-13/pdf/05-18015.pdf</a>.
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The molar comparison of MIR is more consistent with the original
smog chamber experiments, which compared equal molar concentrations of
individual VOC, supporting the selection of ethane as the threshold,
while the mass-based comparison of MIR is consistent with how MIR
values and other reactivity metrics are applied in reactivity-based
emission limits. It is, however, important to note that the mass-based
comparison is less restrictive than the molar-based comparison in that
more compounds would qualify as negligibly reactive.
Given the two goals of the exemption policy articulated in the 2005
Interim Guidance, the EPA believes that ethane continues to be an
appropriate threshold for defining negligible reactivity. And, to
encourage the use of environmentally beneficial substitutions, the EPA
continues to believe that a comparison to ethane on a mass basis
strikes the right balance between a threshold that is low enough to
capture compounds that significantly affect O<INF>3</INF>
concentrations and a threshold that is high enough to exempt some
compounds that may usefully substitute for more highly reactive
compounds.
The 2005 Interim Guidance also noted that concerns have sometimes
been raised about the potential impact of a VOC exemption on
environmental endpoints other than O<INF>3</INF> concentrations,
including fine particle formation, air toxics exposures, stratospheric
O<INF>3</INF> depletion, and climate change. The EPA has recognized,
however, that there are existing regulatory or non-regulatory programs
that are specifically designed to address these issues, and the EPA
continues to believe in general that the impacts of VOC exemptions on
environmental endpoints other than O<INF>3</INF> formation can be
adequately addressed by these programs. The VOC exemption policy is
intended to facilitate attainment of the O<INF>3</INF> National Ambient
Air Quality Standards (NAAQS), and VOC exemption decisions will
continue to be based primarily on consideration of a compound's
contribution to O<INF>3</INF> formation. However, if the EPA determines
that a particular VOC exemption is likely to result in a significant
increase in the use of a compound and that the increased use would pose
a significant risk to human health or the environment that would not be
addressed adequately by existing programs or policies, then the EPA may
exercise its judgment accordingly in deciding whether to grant an
exemption.
The EPA has provided the foregoing discussion of its VOC exemption
policies as background for its assessment of the petition to list HCFO-
1224yd(z) as an exempt compound and its proposed action to grant the
petition. However, the EPA is not reopening the 2005 Interim Guidance
or other aspects of its VOC exemption policy in this proposed rule and
is not seeking comment on these issues.
B. Petition To List HCFO-1224yd(Z) as an Exempt Compound
The AGC Chemicals Americas, Inc. (``AGC'') submitted a petition to
the EPA on July 29, 2020, requesting that (Z)-1-chloro-2,3,3,3-
tetrafluoropropene (also known as HCFO-1224yd(Z); CAS number 111512-60-
8) be exempted from the regulatory definition of VOC. The petition
stated that HCFO-1224yd(Z) has low reactivity (i.e., 0.052 <plus-minus>
0.011g of O<INF>3</INF>/g of HCFO-1224yd(Z))
[[Page 88943]]
compared to the MIR of ethane (0.28 g O<INF>3</INF>/g). The petitioner
indicated that HCFO-1224yd(Z) may be used in refrigeration which uses a
turbo-type refrigerator, a binary generator, a heat recovery heat pump,
etc. As a refrigerant, this compound will not be generally emitted into
the atmosphere on a continuous basis in significant amounts.
Refrigerators will be initially charged and then serviced with HCFO-
1224yd(Z) with minimal losses of refrigerant to the atmosphere over
time, and they will be subject to EPA's regulations related to
servicing and ``venting.'' HCFO-1224yd(Z) has been approved by EPA
through its Significant New Alternatives Policy (SNAP) program as an
acceptable substitute for use in new and retrofitted centrifugal
chillers, positive displacement chillers and industrial process
refrigeration.\2\
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\2\ 84 FR 64765 (Nov. 25, 2019): <a href="https://www.federalregister.gov/documents/2019/11/25/2019-25412/protection-of-stratospheric-ozone-determination-35-for-significant-new-alternatives-policy-program">https://www.federalregister.gov/documents/2019/11/25/2019-25412/protection-of-stratospheric-ozone-determination-35-for-significant-new-alternatives-policy-program</a>.
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AGC has developed HCFO-1224yd(Z) to support reductions in emissions
of greenhouse gases (GHGs). The global warming potential (GWP) for
HCFO-1224yd(Z) is 0.88 for a time horizon of 100 years. HCFO-1224yd(Z)
is relatively short-lived in the atmosphere, with a lifetime of
approximately 20 days. HCFO-1224yd(Z)'s ODP is almost zero (0.00023)
and, leading to an environmental impact that is estimated to be low
especially when compared to the existing alternatives (Tokuhashi et
al., 2018). Hence, HCFO-1224yd(Z) can serve as a replacement for
compounds in several centrifugal and positive displacement chillers
such as ammonia absorption, carbon dioxide, and HFO-1336mzz(Z) among
others with GWP ranging between zero and 630. For industrial process
refrigeration, HCFO-1224yd(Z) has a GWP lower than or comparable to
that of acceptable existing substitutes for new or retrofit equipment
with GWP ranging between zero and 14,800.
Toxicity of HCFO-1224yd(Z) is comparable to or lower than that of
other available substitutes in the same end uses. The toxicity risks
are evaluated through the SNAP program but can also be minimized
through the application of recommended guidance in the Occupational
Alliance for Risk Science's Workplace Environmental Exposure Level
(OARS WEEL), the American Society of Heating, Refrigerating and Air-
Conditioning Engineers safety standards 15 (ASHARE 15) and other
industry standards, as well as the safety data sheet (SDS) and other
safety precautions related to refrigeration and air conditioning
industry.
To support its petition, AGC provided a document on ground-level
atmospheric ozone formation potential from the reactivity of HCFO-
1224yd(Z) with the hydroxyl OH based on calculations using SARPC-11
atmospheric chemical mechanism.\3\ AGC's supplemental technical report
supplied a MIR of HCFO-1224yd(Z) of 0.052 <plus-minus> 0.011 g
O<INF>3</INF>/g HCFO-1224yd(Z) on the mass-based MIR scale. This
reactivity is significantly lower than that of ethane (0.29 <plus-
minus> 0.07 g O<INF>3</INF>/g ethane). The report also addressed
uncertainties around the MIR value calculated and stipulated that the
relative impact on ozone formation will be small when compared to
variability in atmospheric conditions. The report raised a warning
around the chemical mechanism used to predict ozone formation potential
to caution about the need to test whether the predicted value can be
observed in an environmental chamber experiment. The petition did not
include a value for the rate constant k<INF>OH</INF> for the gas-phase
reaction with OH radicals.
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\3\ Carter, W. P. L. 2020. Estimation of the ground-level
atmospheric ozone formation potential of isomers of 1-chloro-
2,3,3,3-tetrafluoro-1-propene, HFCO-1224YD(Z), Report to AGC
Chemicals Americas Company, Exton, PA, USA.
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To address the potential for stratospheric O<INF>3</INF> impacts,
the petitioner specified that, because the atmospheric lifetime of
HCFO-1224yd(Z) due to loss by OH reaction was estimated to be
relatively short, even though HCFO-1224yd(Z) contains chlorine, it is
not expected to contribute to the depletion of the stratospheric
O<INF>3</INF> layer more than other alternatives listed acceptable by
EPA's SNAP program (USEPA, 2019).
III. The EPA's Assessment of the Petition
The EPA is proposing to respond to the petition to revise the EPA's
regulatory definition of VOC for exemption of HCFO-1224yd(Z). This
action is based on consideration of the compound's low contribution to
tropospheric O<INF>3</INF> and the low likelihood of risk to human
health or the environment, including stratospheric O<INF>3</INF>
depletion, toxicity, and climate change. Additional information on
these topics is provided in the following sections.
A. Contribution to Tropospheric Ozone Formation
The rate constant k<INF>OH</INF> for the gas-phase reaction with OH
radicals is measured to be (5.84 <plus-minus> 0.030) 10<SUP>-13</SUP>
cm\3\/molecule-sec at ~298 degrees Kelvin (K) (Tokuhashi et al., 2018).
This k<INF>OH</INF> is more than twice the k<INF>OH</INF> of ethane
(2.4 x 10<SUP>-13</SUP> cm\3\/molecule-sec at ~298 K; Atkinson et al.,
2006) even when uncertainty is considered and, therefore, suggests that
it is more reactive than ethane. In most cases, chemicals with high
k<INF>OH</INF> values also have high MIR values, but the products that
are formed here in subsequent reactions are expected to be
polyfluorinated compounds, which do not contribute to O<INF>3</INF>
formation (Osterstrom et al., 2017). In the case of HCFO-1224yd(Z),
while the k<INF>OH</INF> is relatively high, the calculated maximum
incremental reactivity MIR is very low when compared to that of ethane
based on Carter (2020), provided by the petitioner, and reviewed by
EPA.
Carter (2020) estimates that HCFO-1224yd(Z) has a MIR value of
0.052 <plus-minus> 0.011 g O<INF>3</INF>/g VOC versus 0.29 <plus-minus>
0.07 g O<INF>3</INF>/g VOC for ethane. Therefore, the EPA considers
HCFO-1224yd(Z) to be negligibly reactive and eligible for VOC-exempt
status following the Agency's long-standing policy that compounds
should so qualify where either reactivity metric (k<INF>OH</INF>
expressed on a molar basis or MIR expressed on a mass basis) indicates
that the compound is less reactive than ethane. While the overall
atmospheric reactivity of HCFO-1224yd(Z) was not studied in an
experimental smog chamber, the chemical mechanism derived from other
chamber studies (Carter, 2011) was used to model the complete formation
of O<INF>3</INF> for an entire single day under realistic atmospheric
conditions by Carter (2020). The EPA has assessed the Carter study
provided by the petitioner and believes the calculated MIR value is
reliable.\4\
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\4\ Supporting memo is included in the docket.
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Table 2 presents three reactivity metrics for HCFO-1224yd(Z) as
they compare to ethane.
[[Page 88944]]
Table 2--Reactivities of Ethane and HCFO-1224yd(Z)
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Maximum
incremental Maximum
Compound kOH (cm\3\/molecule-sec) reactivity (MIR) incremental
(g O3/mole VOC) reactivity (MIR)
(g O3/g VOC)
----------------------------------------------------------------------------------------------------------------
Ethane.................................... 2.4 x 10-\13\............... 8.4 0.28 <plus-minus>
0.07
HCFO-1224yd(Z)............................ (5.84 <plus-minus> 0.030) x 7.7 0.052 <plus-minus>
10-\13\. 0.011
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Notes:
kOH value at 298 K for ethane is from Atkinson et al. (2006; page 3626).
kOH value at 300 K for HCFO-1224yd(Z) is from Tokuhashi et al., 2018 (table 1).
Mass-based MIR value (g O3/g VOC) of ethane is from Carter (2011).
Mass-based MIR value (g O3/g VOC) of HCFO-1224yd(Z) is from Carter 2020.
Molar-based MIR (g O3/mole VOC) values were calculated from the mass-based MIR (g O3/g VOC) values using the
number of moles per gram of the relevant organic compound.
The reaction rate of HCFO-1224yd(Z) with the OH radical
(k<INF>OH</INF>) has been measured to be (5.84 <plus-minus> 0.030) x
10<SUP>-13</SUP> cm\3\/molecule-sec (Tokuhashi et al., 2018); other
reactions with O<INF>3</INF> and the nitrate radical were negligibly
small. The corresponding reaction rate of ethane with OH is 2.4 x
10<SUP>-13</SUP> cm\3\/molecule-sec (Atkinson et al., 2006). The data
in table 2 show that HCFO-1224yd(Z) has a higher k<INF>OH</INF> value
than ethane, meaning that it initially reacts more than twice as fast
in the atmosphere as ethane. However, the resulting unsaturated
fluorinated compounds in the atmosphere are short lived and react more
slowly to form O<INF>3</INF> (Baasandorj et al., 2011). The modeled
reactivity based on the mechanism considered by Carter resulted in a
very low maximum incremental reactivity on a mass basis. When compared
to ethane, HCFO-1224yd(Z) has a MIR of 0.052 <plus-minus> 0.011 g
O<INF>3</INF>/g VOC. Hence HCFO-1224yd(Z)'s MIR is less than the fifth
of that of ethane at 0.28 <plus-minus> 0.07 g O<INF>3</INF>/g ethane.
As shown in table 2, HCFO-1224yd(Z)'s MIR on a molar basis is also
somewhat lower than that of ethane. Considering the uncertainty and
variability in the MIR modeling, as described by Carter (2020), we are
confident that the MIR of HCFO-1224yd(Z) is less than that of ethane.
A molecule of HCFO-1224yd(Z) is considerably less reactive than a
molecule of ethane in terms of complete O<INF>3</INF>-forming activity,
as shown by the molar-based MIR (g O<INF>3</INF>/mole VOC) values.
Likewise, one gram of HCFO-1224yd(Z) has a lower capacity than one gram
of ethane to form O<INF>3</INF> in terms of a mass-based MIR. Thus,
following the 2005 Interim Guidance, the EPA finds HCFO-1224yd(Z) to be
eligible for exemption from the regulatory definition of VOC based on
both the molar- and mass-based MIR.
B. Potential Impacts on Other Environmental Endpoints
The EPA's decision to exempt HCFO-1224yd(Z) from the regulatory
definition of VOC is based on our findings above. However, as noted in
the 2005 Interim Guidance, the EPA reserves the right to exercise its
judgment in certain cases where an exemption is likely to result in a
significant increase in the use of a compound and a subsequent
significantly increased risk to human health or the environment. In
this case, the EPA does not find that exemption of HCFO-1224yd(Z) would
result in an increase of risk to human health or the environment,
regarding stratospheric O<INF>3</INF> depletion, toxicity, and climate
change. More information on these topics is provided in the following
sections.
1. Contribution to Stratospheric Ozone Depletion
The SNAP program is the EPA's program to evaluate and regulate
substitutes for end-uses historically using O<INF>3</INF>-depleting
chemicals. Under section 612(c) of the CAA, the EPA is required to
identify and publish lists of acceptable and unacceptable substitutes
for class I or class II O<INF>3</INF>-depleting substances. Per the
SNAP program findings, the ODP of HCFO-1224yd(Z) is zero, which is
significantly less than the ODPs for the [ozone depleting substances]
ODS subject to the phase out of production and consumption under
regulations issued under sections 601-607 of the CAA and consistent
with the Montreal Protocol on Substances that Deplete the Ozone Layer.
The SNAP program has listed HCFO-1224yd(Z) as an acceptable substitute
for chillers and other industrial process refrigeration end-uses
provided in 84 FR 64765, November 25, 2019 (USEPA, 2019).
HCFO-1224yd(Z) is unlikely to contribute to the depletion of the
stratospheric O<INF>3</INF> layer. The O<INF>3</INF> depletion
potential (ODP) of HCFO-1224yd(Z) is expected to be negligible based on
several lines of evidence (Tokuhashi et al., 2018; Guo et al., 2019).
Because HCFO-1224yd(Z)'s atmospheric lifetime is short (20 days
according to Tokuhashi et al., 2018) compared to the timescale for
mixing within the troposphere, it will decay before it has a chance to
reach the stratosphere and, thus, will not participate in O<INF>3</INF>
destruction (Guo et al., 2019).
2. Toxicity
Based on screening assessments of the health and environmental
risks of HCFO-1224yd(Z), the SNAP program expected that users will be
able to use the compound without significantly greater health risks
than presented using other available substitutes for the same end uses
(USEPA, 2019).
The EPA anticipates that HCFO-1224yd(Z) will be used consistent
with the recommendations specified in the manufacturer's SDS (AGC,
2017). According to the SDS, potential health effects from inhalation
of HCFO-1224yd(Z) include drowsiness or dizziness, irritation of the
skin or eyes, or frostbite. These potential health effects are common
to many refrigerants. However, HCFO-1224yd(Z) could cause asphyxiation
if air is displaced by vapors in a confined space. The Workplace
Environmental Exposure Limit (WEEL) committee of the Occupational
Alliance for Risk Science (OARS) reviewed available animal toxicity
data and recommends a WEEL for the workplace of 1000 parts per million
(ppm) (6700 mg/m\3\) \5\ time-weighted average (TWA) for an 8-hour
workday, as later published in 2019 in Toxicology and Industrial Health
(``(Z)-I-Chloro-2,3,3,3-tetrafluoropropene,'' 2020).\6\ This WEEL was
derived based
[[Page 88945]]
on a 4-week, GLP-compliant inhalation toxicity study in rats (AGC,
2016), based on the point of departure a NOAEL of 40,000 ppm. This was
also the NOAEL for the developmental toxicity study where developmental
effects were only observed in female rats. The EPA expects that users
will be able to meet the WEEL and address potential health risks by
following requirements and recommendations in the SDS and other safety
precautions common to the refrigeration and air conditioning industry.
---------------------------------------------------------------------------
\5\ Occupational Alliance for Risk Science (OARS-WEELs)- HCFO-
1224yd(Z)), 2017: <a href="https://www.tera.org/OARS/PDF_documents/09_hcfo-1224yd">https://www.tera.org/OARS/PDF_documents/09_hcfo-1224yd</a>(z)-weel-document-final-2017.pdf.
\6\ (``(Z)-I-Chloro-2,3,3,3-tetrafluoropropene (HCFO-1224yd(Z))
(2017). (2019). Toxicology and Industrial Health, 36(5), 305-309.
<a href="https://doi.org/10.1177/0748233720930548">https://doi.org/10.1177/0748233720930548</a>.
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HCFO-1224yd(Z) is not regulated as a hazardous air pollutant (HAP)
under title I of the CAA. Also, it is not listed as a toxic chemical
under section 313 of the Emergency Planning and Community Right-to-Know
Act (EPCRA).
The Toxic Substances Control Act (TSCA) gives the EPA authority,
among other things, to evaluate and, if necessary, address risks of
injury to health or the environment from new chemical substances before
such substances may be manufactured (including imported). Section 5 of
TSCA requires manufacturers and importers to notify the EPA before
manufacturing a new chemical substance or manufacturing or processing
any chemical substance for a use which the Administrator has determined
is a significant new use. When EPA receives such notice, it assesses
whether sufficient information is available to permit a reasoned
evaluation of the health and environmental effects of the substance or
use and whether manufacturing, processing, distribution in commerce,
use, or disposal of the substance (or any combination of such
activities) presents, may present, or is not likely to present an
unreasonable risk. Based on its review of a premanufacture notice (PMN)
for HCFO-1224yd(Z), the EPA signed a consent order under TSCA section
5(e) to protect against an unreasonable risk of injury to health or the
environment. EPA also subsequently issued a Significant New Use Rule
(SNUR) under TSCA that requires submission of a Significant New Use
Notice (SNUN) to the EPA at least 90 days before manufacturing or
processing of HCFO-1224yd(Z) for any significant new use. The required
notification will provide the EPA with the opportunity to evaluate any
intended significant new use before it occurs and, if necessary, to
issue orders to address any potential unreasonable risk to human health
or the environment.
HCFO-1224yd(Z) is one of the class of substances generally referred
to as per- and polyfluoroalkyl substances (PFAS). Many PFAS compounds
represent a public health concern due to their toxicity and persistence
in the environment. As a class, they are also highly varied, and
variations in structure may result in (yet unknown) differences in
environmental mobility and toxicity. The agency's ongoing work
addressing PFAS does not currently address HCFO-1224yd(Z) specifically;
however, the exposure limits and SNAP screening assessment noted above
give us confidence that the use of this compound will not pose an
unreasonable risk to human health. EPA also believes that the impacts
of PFAS will be adequately addressed by regulatory and non-regulatory
programs specifically designed to address those impacts.\7\
---------------------------------------------------------------------------
\7\ Interim Guidance on Control of Volatile Organic Compounds in
Ozone State Implementation Plans, 2005, US Environmental Protection
Agency, Document Number 05-18015 (70 FR 54046). And could be found
at this link: <a href="https://www.govinfo.gov/content/pkg/FR-2005-09-13/pdf/05-18015.pdf">https://www.govinfo.gov/content/pkg/FR-2005-09-13/pdf/05-18015.pdf</a>.
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3. Contribution to Climate Change
The Intergovernmental Panel on Climate Change (IPCC) Fifth
Assessment Report (IPCC AR5) does not provide an estimate for HCFO-
1224yd(Z)'s global warming potential (GWP).\8\ The HCFO-1224yd(Z) GWP
on a 100-year time horizon was calculated to be 5.4 in one study by
Tokuhashi et al. (2018), but the same study reported an experimental
chamber value of 0.88 and a lifetime of 20 days. This is consistent
with the Scientific Assessment of Ozone Depletion by the chemical
sciences laboratory (NOAA, 2022) where the GWP was found to be smaller
than one under all reactivity efficiencies and recommended adjustments.
These authors also calculated an inflated radiation or IR spectrum from
a theoretical model using density functional theory (DFT) for HCFO-
1224yd(Z). That calculation gives a GWP of 5.4. While the theoretical
value differs substantially on a percentage basis from the measured
value, the GWP based on the experimental measurement is expected to be
the more accurate given the large uncertainties in the calculated
molecular model which tend to be unknown and high. Either value is 1-2
orders of magnitude lower than the GWP for the refrigerant(s) that
HCFO-1224yd(Z) is designed to replace. HCFO-1224yd(Z) has a GWP below
one indicating that it has less radiating impact than that of
CO<INF>2</INF> over a 100-year time period (GWP<INF>100</INF>). Species
with double bonds assembled in the Intergovernmental Panel on Climate
Change Fifth Assessment Report (table 8.A.1) show lower GWP than
species without a double bond. According to the SNAP rule, HCFO-
1224yd(Z)'s GWP is smaller than one and is comparable to or lower than
those of some of the substitutes such as used in new chillers, ammonia
absorption, carbon dioxide (CO<INF>2</INF>), and hydro-fluoro-olefin
(HFO-1336mzz(Z)), and for new and retrofit chillers with GWPs ranging
from 0 to 630. (USEPA, 2019). Both the calculated and the observed
values of HCFO-1224yd(Z)'s GWP are lower than that of ethane determined
to be 10.2.\9\
---------------------------------------------------------------------------
\8\ IPCC, 2013: Climate Change 2013: Chapter 8, Myhre, G., D.
Shindell, F.-M. Br[eacute]on, W. Collins, J. Fuglestvedt, J. Huang,
D. Koch, J.-F. Lamarque, D. Lee, B. Mendoza, T. Nakajima, A. Robock,
G. Stephens, T. Takemura and H. Zhang, 2013: Anthropogenic and
Natural Radiative Forcing. In: Climate Change 2013: The Physical
Science Basis. Contribution of Working Group I to the Fifth
Assessment Report of the Intergovernmental Panel on Climate Change
[Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J.
Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)].
Cambridge University Press, Cambridge, United Kingdom and New York,
NY, USA. <a href="https://www.ipcc.ch/site/assets/uploads/2018/02/WG1AR5_Chapter08_FINAL.pdf">https://www.ipcc.ch/site/assets/uploads/2018/02/WG1AR5_Chapter08_FINAL.pdf</a>.
\9\ Lifetimes, direct and indirect radiative forcing, and global
warming potentials of ethane (C2H6), propane (C3H8), and butane
(C4H10): <a href="https://rmets.onlinelibrary.wiley.com/doi/full/10.1002/asl.804">https://rmets.onlinelibrary.wiley.com/doi/full/10.1002/asl.804</a>.
---------------------------------------------------------------------------
C. Conclusions
The EPA finds that HCFO-1224yd(Z) is negligibly reactive with
respect to its contribution to tropospheric O<INF>3</INF> formation
and, thus, may be exempted from the EPA's definition of VOC in 40 CFR
51.100(s). HCFO-1224yd(Z) has been listed as acceptable for use in new
and retrofitted centrifugal chillers, positive displacement chillers
and industrial process refrigeration under the SNAP program (USEPA,
2019). The EPA has also determined that exemption of HCFO-1224yd(Z)
from the regulatory definition of VOC will not result in an increase of
risk to human health and the environment, and, to the extent that use
of this compound does have impacts on other environmental endpoints,
those impacts are adequately managed by existing programs. For example,
HCFO-1224yd(Z) has a similar or lower stratospheric O<INF>3</INF>
depletion potential than available substitutes in those end-uses, and
the toxicity risk from using HCFO-1224yd(Z) is not significantly
greater than the risk from using other available alternatives for the
same uses. The EPA has concluded that non-tropospheric O<INF>3</INF>-
related risks associated with potential increased use of HCFO-1224yd(Z)
are adequately managed by SNAP. The EPA does not expect significant use
of HCFO-1224yd(Z) in applications not covered by the SNAP program. To
the extent that
[[Page 88946]]
the compound is used in other applications not already reviewed under
SNAP or under the New Chemicals Program under TSCA, the SNUR in place
under TSCA requires that any significant new use of a chemical be
reported to the EPA using a SNUN. Any significant new use of HCFO-
1224yd(Z) would, thus, need to be evaluated by the EPA, and the EPA
will continually review the availability of acceptable substitute
chemicals under the SNAP program.
IV. Proposed Action
The EPA is responding to the petition by proposing to revise its
regulatory definition of VOC at 40 CFR 51.100(s) to add HCFO-1224yd(Z)
to the list of compounds that are exempt from the regulatory definition
of VOC because it is less reactive than ethane based on a comparison of
mass-based MIR and molar-based MIR metrics and is, therefore,
considered negligibly reactive. As a result of this action, if an
entity uses or produces this compound and is subject to the EPA
regulations limiting the use of VOC in a product, limiting the VOC
emissions from a facility, or otherwise controlling the use of VOC for
purposes related to attaining the O<INF>3</INF> NAAQS, this compound
will not be counted as a VOC in determining whether these regulatory
obligations have been met. This action would affect whether this
compound is considered a VOC for State regulatory purposes to reduce
O<INF>3</INF> formation, if a State relies on the EPA's regulatory
definition of VOC. States are not bound to exclude from control as a
VOC those compounds that the EPA has found to be negligibly reactive.
However, no State may take credit for controlling this compound in its
O<INF>3</INF> control strategy. Consequently, reductions in emissions
for this compound will not be considered or counted in determining
whether States have met the rate of progress requirements for VOC in
State Implementation Plans or in demonstrating attainment of the
O<INF>3</INF> NAAQS.
V. Statutory and Executive Order Reviews
Additional information about these statutes and Executive orders
can be found at <a href="https://www.epa.gov/laws-regulations/laws-and-executive-orders">https://www.epa.gov/laws-regulations/laws-and-executive-orders</a>.
A. Executive Order 12866: Regulatory Planning and Review and Executive
Order 14094: Modernizing Regulatory Review
This action is not a significant regulatory action as defined in
Executive Order 12866, as amended by Executive Order 14094, and was
therefore not subject to a requirement for Executive Order 12866
review.
B. Paperwork Reduction Act (PRA)
This action does not impose an information collection burden under
the PRA. It does not contain any recordkeeping or reporting
requirements.
C. Regulatory Flexibility Act (RFA)
I certify that this action will not have a significant economic
impact on a substantial number of small entities under the RFA. This
action will not impose any requirements on small entities. This action
removes HCFO-1224yd(Z) from the regulatory definition of VOC and,
thereby, relieves manufacturers, distributers, and users of the
compound from tropospheric O<INF>3</INF> requirements to control
emissions of the compound.
D. Unfunded Mandates Reform Act (UMRA)
This action does not contain an unfunded mandate as described in
UMRA, 2 U.S.C. 1531-1538, and does not significantly or uniquely affect
small governments. This action imposes no enforceable duty on any
State, local or Tribal governments, or the private sector.
E. Executive Order 13132: Federalism
This action does not have federalism implications. It will not have
substantial direct effects on the States, on the relationship between
the national government and the States, or on the distribution of power
and responsibilities among the various levels of government.
F. Executive Order 13175: Consultation and Coordination With Indian
Tribal Governments
This action does not have Tribal implications, as specified in
Executive Order 13175. This proposed rule removes HCFO-1224yd(Z) from
the regulatory definition of VOC and, thereby, relieves manufacturers,
distributers, and users from tropospheric O<INF>3</INF> requirements to
control emissions of the compound. Thus, Executive Order 13175 does not
apply to this action.
G. Executive Order 13045: Protection of Children From Environmental
Health and Safety Risks
Executive Order 13045 directs Federal agencies to include an
evaluation of the health and safety effects of the planned regulation
on children in Federal health and safety standards and explain why the
regulation is preferable to potentially effective and reasonably
feasible alternatives. This action is not subject to Executive Order
13045, because it is not economically significant as defined in
Executive Order 12866, and because the EPA does not believe the
environmental health or safety risks addressed by this action present a
disproportionate risk to children. Our assessment is consistent with
the SNAP finding that the conditional use of this chemical will
guarantee the reduction of exposure risks to the general population
particularly the most sensitive population (e.g., children). Since
HCFO-1224yd(Z) is utilized in specific industrial applications where
children are not present and dissipates quickly (e.g., lifetime of 22
days) with short-lived end products, there is no exposure or
disproportionate risk to children. This action removes HCFO-1224yd(Z)
from the regulatory definition of VOC and, thereby, relieves
manufacturers, distributers, and users from tropospheric O<INF>3</INF>
requirements to control emissions of the compound.
H. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution or Use
This action is not subject to Executive Order 13211, because it is
not a significant regulatory action under Executive Order 12866.
I. National Technology Transfer and Advancement Act (NTTAA)
This rulemaking does not involve technical standards.
J. Executive Order 12898: Federal Actions To Address Environmental
Justice in Minority Populations and Low-Income Populations and
Executive Order 14096: Revitalizing Our Nation's Commitment to
Environmental Justice for All
The EPA believes that the human health and environmental conditions
that exist prior to this action do not result in disproportionate and
adverse effects on communities with EJ concerns. As we found no data
available to support the opposite, we addressed the human health and
environmental risks by this proposed action to the greatest ability
feasible. This action was developed in accordance with agency guidance
on environmental justice.
The EPA believes that this action in not likely to result in new
disproportionate and adverse effects on communities with environmental
justice concerns. This action removes HCFO-1224yd(Z) from the
regulatory definition
[[Page 88947]]
of VOC and, thereby, relieves manufacturers, distributers, and users of
the compound from tropospheric O<INF>3</INF> requirements to control
emissions of the compound. It will in fact help States focus on more
photochemically reactive chemicals preventing more formation of Ozone
and consequently more adverse related health and environmental effects.
K. Judicial Review
Under section 307(b)(1) of the CAA, petitions for judicial review
of this action must be filed in the United States Court of Appeals for
the District of Columbia Circuit Court within 60 days from the date the
proposed action is published in the Federal Register. Filing a petition
for review by the Administrator of this proposed action does not affect
the finality of this action for the purposes of judicial review nor
does it extend the time within which a petition for judicial review
must be filed and shall not postpone the effectiveness of such action.
Thus, any petitions for review of this action related to the exemption
of HCFO-1224yd(Z) from the regulatory definition of VOC must be filed
in the Court of Appeals for the District of Columbia Circuit within 60
days from the date proposed action is published in the Federal
Register.
VII. References
AGC. (2016) (Z)-1-Chloro-2,3,3,3-tetrafluoropropene Refrigerant Gas
Safety Data Sheet. ASAHI GLASS CO., LTD. Tokyo 100-8405, Japan
August 2016.
AGC Chemicals. (2017). AMOLEA[supreg] 1224yd, Technical Information,
ASAHI Glass Co., Ltd. (pp. 1-18).
Atkinson, R., Baulch, D.L., Cox, R.A., Crowley, J.N., Hampson, Jr.,
R.F., Hynes, R.G., Jenkin, M.E., Kerr, J.A., Rossi, M.J., and Troe,
J. (2006) Evaluated kinetic and photochemical data for atmospheric
chemistry: Volume II--gas phase reactions of organic species. Atmos.
Chem. Phys. 6: 3625-4055.
Baasandorj, M., Ravishankara, A.R., Burkholder, J.B. (2011)
Atmospheric chemistry of (Z)-CF3CH=CHCF3: OH radical reaction rate
coefficient and global warming potential. J Phys Chem A. 2011 Sep
29;115(38):10539-49. doi: 10.1021/jp206195g.
Carter, W.P.L. (1994) Development of ozone reactivity scales for
volatile organic compounds. J. Air Waste Manage, 44: 881-899.
Carter, W.P.L. (2011) SAPRC Atmospheric Chemical Mechanisms and VOC
Reactivity Scales, at https://www.engr.ucr.edu/~carter/SAPRC/. Last
updated in Sept. 14, 2013. Tables of Maximum Incremental Reactivity
(MIR) Values available at <a href="https://www.arb.ca.gov/regact/2009/mir2009/mir2009.htm">https://www.arb.ca.gov/regact/2009/mir2009/mir2009.htm</a>. May 11, 2011.
Osterstrom, F.F., Andersen, S.T., S[oslash]lling, T.I., Nielsena,
OJ., and Andersen, M.P.S. (2017) Atmospheric chemistry of Z- and E-
CF3CH--CHCF3: Phys.Chem.Chem.Phys., 2017, 19, 735.
Tokuhashi, K., Uchimaru, T., Takizawa, K., & Kondo, S. (2018). Rate
Constants for the Reactions of OH Radical with the (E)/(Z) Isomers
of CF3CF=CHCl and CHF2CF=CHCl. The Journal of Physical Chemistry A,
122(12), 3120-3127. <a href="https://doi.org/10.1021/acs.jpca.7b11923">https://doi.org/10.1021/acs.jpca.7b11923</a>.
USEPA, 2019. Protection of Stratospheric Ozone: Determination 35 for
Significant New Alternatives Policy Program November 25, 2019. 84 FR
64765. Available online at: <a href="https://www.govinfo.gov/content/pkg/FR-2019-11-25/pdf/2019-25412.pdf">https://www.govinfo.gov/content/pkg/FR-2019-11-25/pdf/2019-25412.pdf</a>.
List of Subjects in 40 CFR Part 51
Environmental protection, Administrative practice and procedure,
Air pollution control, Ozone, Reporting and recordkeeping requirements,
Volatile organic compounds.
Michael S. Regan,
Administrator.
For reasons stated in the preamble, title 40, chapter I of the Code
of Federal Regulations is proposed to be amended as follows:
PART 51--REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF
IMPLEMENTATION PLANS
0
1. The authority citation for part 51 continues to read as follows:
Authority: 23 U.S.C. 101; 42 U.S.C. 7401-7671q.
Subpart F--Procedural Requirements
0
2. Section 51.100 is amended by revising paragraph (s)(1) introductory
text to read as follows:
Sec. 51.100 Definitions.
* * * * *
(s) * * *
(1) This includes any such organic compound other than the
following, which have been determined to have negligible photochemical
reactivity: methane; ethane; methylene chloride (dichloromethane);
1,1,1-trichloroethane (methyl chloroform); 1,1,2-trichloro-1,2,2-
trifluoroethane (CFC-113); trichlorofluoromethane (CFC-11);
dichlorodifluoromethane (CFC-12); chlorodifluoromethane (HCFC-22);
trifluoromethane (HFC-23); 1,2-dichloro 1,1,2,2-tetrafluoroethane (CFC-
114); chloropentafluoroethane (CFC-115); 1,1,1-trifluoro 2,2-
dichloroethane (HCFC-123); 1,1,1,2-tetrafluoroethane (HFC-134a); 1,1-
dichloro 1-fluoroethane (HCFC-141b); 1-chloro 1,1-difluoroethane (HCFC-
142b); 2-chloro-1,1,1,2-tetrafluoroethane (HCFC-124); pentafluoroethane
(HFC-125); 1,1,2,2-tetrafluoroethane (HFC-134); 1,1,1-trifluoroethane
(HFC-143a); 1,1-difluoroethane (HFC-152a); parachlorobenzotrifluoride
(PCBTF); cyclic, branched, or linear completely methylated siloxanes;
acetone; perchloroethylene (tetrachloroethylene); 3,3-dichloro-
1,1,1,2,2-pentafluoropropane (HCFC-225ca); 1,3-dichloro-1,1,2,2,3-
pentafluoropropane (HCFC-225cb); 1,1,1,2,3,4,4,5,5,5-decafluoropentane
(HFC 43-10mee); difluoromethane (HFC-32); ethylfluoride (HFC-161);
1,1,1,3,3,3-hexafluoropropane (HFC-236fa); 1,1,2,2,3-pentafluoropropane
(HFC-245ca); 1,1,2,3,3-pentafluoropropane (HFC-245ea); 1,1,1,2,3-
pentafluoropropane (HFC-245eb); 1,1,1,3,3-pentafluoropropane (HFC-
245fa); 1,1,1,2,3,3-hexafluoropropane (HFC-236ea); 1,1,1,3,3-
pentafluorobutane (HFC-365mfc); chlorofluoromethane (HCFC-31); 1
chloro-1-fluoroethane (HCFC-151a); 1,2-dichloro-1,1,2-trifluoroethane
(HCFC-123a); 1,1,1,2,2,3,3,4,4-nonafluoro-4-methoxy-butane
(C<INF>4</INF>F<INF>9</INF>OCH<INF>3</INF> or HFE-7100); 2-
(difluoromethoxymethyl)-1,1,1,2,3,3,3-heptafluoropropane
((CF<INF>3</INF>)<INF>2</INF>CFCF<INF>2</INF>OCH<INF>3</INF>); 1-
ethoxy-1,1,2,2,3,3,4,4,4-nonafluorobutane
(C<INF>4</INF>F<INF>9</INF>OC<INF>2</INF>H<INF>5</INF> or HFE-7200); 2-
(ethoxydifluoromethyl)-1,1,1,2,3,3,3-heptafluoropropane
((CF<INF>3</INF>)<INF>2</INF>CFCF<INF>2</INF>OC<INF>2</INF>H<INF>5</INF>
); methyl acetate; 1,1,1,2,2,3,3-heptafluoro-3-methoxy-propane (n-
C3F7OCH3, HFE-7000); 3-ethoxy- 1,1,1,2,3,4,4,5,5,6,6,6-dodecafluoro-2-
(trifluoromethyl) hexane (HFE-7500); 1,1,1,2,3,3,3-heptafluoropropane
(HFC 227ea); methyl formate (HCOOCH3); 1,1,1,2,2,3,4,5,5,5-decafluoro-
3-methoxy-4-trifluoromethyl-pentane (HFE-7300); propylene carbonate;
dimethyl carbonate; trans-1,3,3,3-tetrafluoropropene;
HCF<INF>2</INF>OCF<INF>2</INF>H (HFE-134);
HCF<INF>2</INF>OCF<INF>2</INF>OCF<INF>2</INF>H (HFE-236cal2);
HCF<INF>2</INF>OCF<INF>2</INF>CF<INF>2</INF>OCF<INF>2</INF>H (HFE-
338pcc13);
HCF<INF>2</INF>OCF<INF>2</INF>OCF<INF>2</INF>CF<INF>2</INF>OCF<INF>2</INF>
H (H-Galden 1040x or H-Galden ZT 130 (or 150 or 180)); trans 1-chloro-
3,3,3-trifluoroprop-1-ene; 2,3,3,3-tetrafluoropropene; 2-amino-2-
methyl-1-propanol; t-butyl acetate; 1,1,2,2- Tetrafluoro -1-(2,2,2-
trifluoroethoxy) ethane; cis-1,1,1,4,4,4-hexafluorobut-2-ene (HFO-
1336mzz-Z); (Z)-1-chloro-2,3,3,3-tetrafluoropropene (HCFO-1224yd(Z));
and perfluorocarbon compounds which fall into these classes:
* * * * *
[FR Doc. 2024-25971 Filed 11-8-24; 8:45 am]
BILLING CODE 6560-50-P
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This is legal information, not legal advice. Laws vary by jurisdiction and change frequently. Always verify current law with official sources and consult a licensed attorney in your jurisdiction for advice on your specific situation.