MEMORANDUM

To: Debbie Ottinger, EPA

CC: Don Wuebbles, University of Illinois

From: Mollie Averyt, Becky Ferenchiak, Mark Flugge, and Kasey Knoell, ICF

Date: July 14, 2014

Re: Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP (EPA 

Task Order EP-B14H-00017, ICF Task Order 022: Support for Implementing and Refining 

Mandatory GHG Reporting Requirements for Various Emitters of Fluorinated GHGs, Task 3: 

Support for Evaluation of GWPs)

This memorandum presents a summary of an ICF analysis to develop default Global Warming 

Potentials (GWPs) for fluorinated compounds without peer-reviewed GWPs. These default GWPs are 

being considered for inclusion in the proposed rule, Greenhouse Gas Reporting Program: Addition of 

Global Warming Potentials (EPA Docket No. EPA-HQ-OAR-2009-0927, hereinafter referred to as 

“Proposed Rule to Add GWPs”). This memorandum also includes an ICF analysis to review 

comments received on the default GWPs that were included in the Proposed Amendments to Subpart 

L. The purpose of the analysis is to:

1. Consider which sets of compounds should be used as the basis for default GWPs for the 

different groups of fluorinated GHGs whose GWPs do not appear on Table A-1,

2. Calculate the average and the standard deviation of the GWPs for these groups, and

3. Suggest possible default GWPs by rounding the average for each group to one or two 

significant figures.

The remainder of this memorandum is organized into the following sections:

I. Summary

II. Analysis Method for Determining Default GWP Groups

III. Comparison between Defaults and Estimated GWPs for Several F-GHGs 

IV. Evaluation of Analysis Method by Dr. Wuebbles and Recommendations 

V. References

Appendix A: F-GHGs by Fluorinated GHG Group

Appendix B: Default GWPs Based on AR5 GWPs

Appendix C: Evaluation of Default GWPs Considering Numerical and Chemical Outliers

Appendix D: Evaluation of the Comments Received on the Proposed Amendments to Subpart L

The complete results of the analysis are contained in the spreadsheet “Subpart L Rule Default GWP 

Chemical Group Analysis_Comment Analysis_7-9-2014.xlsx.” 

Please contact Mollie Averyt at 202-862-1569 (mollie.averyt@icfi.com) with any questions or 

comments.
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

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I. Summary

Through the Greenhouse Gas Reporting Program (GHGRP), the U.S. Environmental Protection Agency 

(EPA) receives reports of emissions of numerous fluorinated greenhouse gases (GHGs) and heat transfer 

fluids (HTFs) that do not have GWPs listed on Table A-1, the GHGRP’s compendium of GWPs. EPA is 

proposing to add chemical-specific and default GWPs to Table A-1 to address this situation. Specifically, 

EPA is proposing to add approximately 100 chemical-specific GWPs published by the Intergovernmental 

Panel on Climate Change (IPCC) in their Fifth Assessment Report (AR5) (Myhre et al. 2013) in the fall of 

2013. For the fluorinated GHGs and HTFs reported under the GHGRP that do not have chemical-specific 

GWPs in either Table A-1 or AR5, EPA is proposing to add default GWPs. These default GWPs would be 

assigned based on the fluorinated GHG group to which the fluorinated GHG and HTF belonged, based on 

chemical structure. Default GWPs would ensure that the atmospheric impacts of all fluorinated GHGs 

and HTFs are reflected in facility calculations and carbon dioxide equivalent (CO2e) emissions totals.

In developing the fluorinated GHG groups and associated default GWPs, the goal is to model the GWPs 

of compounds that belong to each group (but whose GWPs are not on Table A-1) with as much accuracy 

and precision as possible. EPA is applying the following criteria to assess potential compound groups: (1) 

collectively, the compound groups should span the full range of atmospheric behavior (atmospheric 

lifetimes and GWPs) observed among fluorinated GHGs, (2) within each compound group, the 

compounds should be chemically similar and exhibit similar atmospheric behavior, and (3) compounds 

whose atmospheric behavior is likely to be different from that of any of the compounds whose GWPs 

are being modeled should be excluded from the calculation. However, numerical outliers should be

included in the calculation when the possibility exists that such outliers may also occur among the 

fluorinated GHGs whose GWPs are being modeled.

ICF previously performed an analysis based on these criteria to develop default GWPs that were 

proposed for purposes of reporting emissions under subpart L.1 EPA proposed five fluorinated GHG 

groups and associated default GWPs in the Proposed Amendments to Subpart L2, as shown in Table 1. 

Table 1. Fluorinated GHG Groups and Associated Default GWPs in Proposed Amendments to Subpart L

Fluorinated GHG Group

GWP in Proposed 

Amendments to 

Subpart L (100-yr)

Average 

GWP

Standard 

Deviation

of GWP

Fully fluorinated GHGs 10,000 9,857 3,450

Saturated hydrofluorocarbons (HFCs) 2,200 2,187 3,346

Saturated hydrofluoroethers (HFEs) and saturated 

hydrochlorofluoroethers (HCFEs)a

1,600 1,536 2,536

Unsaturated perfluorocarbons (PFCs), unsaturated HFCs, 

unsaturated hydrochlorofluorocarbons (HCFCs), 

unsaturated HFEs, and fluorinated ketones

1 0.42 0.62

Other fluorinated GHGsb 100 112 177

a The average GWP and standard deviation for this group were revised from 1,559 and 2,551, respectively, after including 2-

Chloro-1,1,2-trifluoro-1-methoxyethane, which was previously miscategorized in “Other fluorinated GHGs.”

b The average GWP and standard deviation for this group were revised from 103 and 183, respectively, after removing 

fluorotelomer alcohols and fluorinated aldehydes, which were previously categorized in “Other fluorinated GHGs,” which at the 

time was the most appropriate category.

 

1 “Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP,” available in docket EPA-HQ-OAR2009-0927.

2 Greenhouse Gas Reporting Program: Amendments and Confidentiality Determinations for Fluorinated Gas Production (78 FR 

69337, November 19, 2013). 
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

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Three commenters, DuPont, 3M, and the American Chemistry Council (ACC) provided comments 

regarding the chemical groups and associated GWPs of fluorinated gases in the Proposed Amendments 

to Subpart L. The commenters requested that EPA split the third group (saturated HFEs and saturated 

HCFEs) into two, expand the fourth group (unsaturated PFCs, unsaturated HFCs, unsaturated HCFCs, 

unsaturated HFEs, and fluorinated ketones), and add two additional groups, fluorotelomer alcohols and 

fluorinated GHGs with carbon-iodine bonds, to increase the precision and accuracy of the default GWPs 

applied to the chemicals in these groups. The commenters stated that five types of chemicals, including 

unsaturated fluorinated ethers, unsaturated halogenated esters, fluorinated aldehydes, fluorotelomer 

alcohols, and fluorinated GHGs with carbon iodine bonds, would have been assigned GWPs that were 

too high if they had remained in the “Other fluorinated GHGs” category (group 5) as defined in the 

proposed rule. They further stated that two types of saturated HFEs and HCFEs would have been 

assigned GWPs that were, on average, either too high (for partially segregated saturated HFEs and 

HCFEs) or too low (for non-segregated saturated HFEs and HCFEs). These comments were reviewed and 

the fluorinated GHG groups and associated default GWPs were reevaluated for the Proposed Rule to 

Add GWPs. A brief summary and analysis of the GWP-related comments on the Proposed Amendments 

to Subpart L appears as Appendix D to this memorandum. A detailed summary and response to all the 

comments on the Proposed Amendments to Subpart L will be included in docket number EPA-HQ-OAR2009-0927 when those amendments are finalized.

EPA is now proposing eight default GWP values based on fluorinated GHG groups. These default GWPs 

would be added to Table A-1 and would apply to fluorinated GHGs and HTFs not otherwise listed on 

Table A-1. The proposed fluorinated GHG groups are listed in Table 2, below.

Table 2. Fluorinated GHG Groups and Associated Default GWPs for Proposed Rule to Add GWPs

Fluorinated GHG Group

GWP in Proposed Rule 

to Add GWPs

(100-year)

Fully fluorinated GHGs 10,000

Saturated hydrofluorocarbons (HFCs) 2,200

Non-segregated saturated hydrofluoroethers (HFEs)

Non-segregated saturated hydrochlorofluoroethers (HCFEs) 2,400

Partially segregated saturated hydrofluoroethers (HFEs)

Partially segregated saturated hydrochlorofluoroethers (HCFEs) 200

Unsaturated perfluorocarbons (PFCs)

Unsaturated HFCs and HCFCs

Unsaturated halogenated ethers 

Unsaturated halogenated esters

Fluorinated ketones

Fluorinated aldehydes

1

Fluorotelomer alcohols 1

Fluorinated GHGs with one or more carbon-iodine bond 1

Other fluorinated GHGs 110

For each fluorinated GHG group, EPA is basing the proposed default GWPs on the average of the 

chemical-specific GWPs of chemicals that belong to that group and that are either on Table A-1 or are 

proposed to be added to Table A-1 under the Proposed Rule to Add GWPs. The proposed fluorinated 

GHG groups and associated GWPs are listed in Appendix B. The fluorinated GHG groups are based 

primarily on chemical structure, which is correlated with atmospheric lifetime and GWP. Thus, within 

each group, GWPs fall into a relatively limited range, and among the groups, GWPs vary significantly. 
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

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This permits default GWPs to be established with more precision than is possible with larger or more 

diverse sets of fluorinated GHGs. 

II. Analysis Method for Determining Default GWP Groups

In order to establish different compound groups and evaluate potential default GWPs for each group, 

ICF analyzed the chemical structure, GWPs, and atmospheric lifetimes of the fluorinated GHGs with 

peer-reviewed GWPs. The F-GHGs with peer-reviewed GWPs include the compounds on Table A-1 and

the compounds in the IPCC Fifth Assessment Report (AR5). As noted above, ICF also considered the 

comments on the Proposed Amendments to Subpart L.

One hundred and two F-GHGs from AR5 and one F-GHG from the IPCC Fourth Assessment Report (AR4) 

(Forster et al. 2007) (i.e., 103 F-GHGs in total) that are not included in the current Table A-1 are included 

in this analysis. For compounds that are included in the current Table A-1, ICF used the GWPs from Table 

A-1 as they were updated in the “2013 Revisions to the Greenhouse Gas Reporting Rule and Proposed 

Confidentiality Determinations for New or Substantially Revised Data Elements; Final Rule” (78 FR 

71904; November 3, 2013), with the exception of sevoflurane, for which the AR5 GWP was used. For 

compounds that are included only in AR5, ICF used the GWP from AR5 in the analysis, with the 

exception of several very short-lived compounds whose GWPs were listed in AR5 as “<1.” In order to 

increase the accuracy of the default GWP analysis, precise GWPs were calculated and used in this 

analysis for these compounds using the atmospheric lifetime and the corrected radiative efficiency 

provided in the AR5.

This analysis resulted in eight main model groups (Table 3) based on chemical structure. As was the case 

for the fluorinated GHG groups included in the Proposed Amendments to Subpart L, these groups

exclude compounds that are chemically different (i.e., that are not fluorocarbons and are therefore 

chemical outliers) from the compounds whose GWPs are being modeled, but they include compounds

whose GWPs are unusually high or low (i.e., numerical outliers). ICF also analyzed variants of the groups 

that include chemical outliers and exclude numerical outliers; this analysis is available in Appendix C. 

Also like the fluorinated GHG groups included in the Proposed Amendments to Subpart L, the groups 

include chemically similar chlorine-containing compounds that are defined as fluorinated GHGs (i.e., are 

not regulated as ozone-depleting compounds under 40 CFR part 82). 

The average and standard deviation of the GWPs of the compounds within each model group were 

calculated. The suggested GWP for each model group is equal to the average GWP of the F-GHGs within 

that model group, rounded to either one or two significant figures.

Table 3 presents the proposed fluorinated GHG groups with the corresponding average, standard 

deviation, and relative standard deviation of the GWPs for each group. As can be seen by comparing 

Table 3 to Table 1, the additions and changes to the fluorinated GHG groups that were included in the 

Proposed Amendments to Subpart L are likely to improve the accuracy and precision of the default 

GWPs. This improvement is driven by the relationship between the structural criteria used to break out 

the new groups (and subgroups) and atmospheric lifetime. As discussed further in Appendix D and in 

“Analysis of Atmospheric Lifetimes, Radiative Efficiencies, and Global Warming Potentials of Saturated 

Hydrofluoroethers by Number of Carbon-Hydrogen and Carbon-Fluorine Bonds” (available in Docket 
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 4

EPA-HQ-OAR-2009-0927), atmospheric lifetime is the key factor in determining the 100-year GWPs of 

most fluorinated GHGs.3

Table 3. Average, Standard Deviation, and Relative Standard Deviation of GWPs of Fluorinated GHG 

Groups 

Fluorinated GHG Group Proposed 

GWP

Average 

GWP 

Standard 

Deviation

Relative 

Standard 

Deviation

Number 

of 

Chemicals 

in Group

Fully fluorinated GHGs 10,000 9,857 3,450 35% 5

Saturated hydrofluorocarbons (HFCs) 2,200 2,187 3,346 153% 26

Partially segregated saturated HFEs and HCFEs 200 204 227 111% 25

Non-segregated saturated HFEs and HCFEs 2,400 2,436 2,967 122% 37

Unsaturated PFCs 1 0.66 0.96 146% 6

Unsaturated HFCs and unsaturated HCFCs 1 0.38 0.51 134% 14

Unsaturated halogenated ethers 1 0.11 - - 2

Unsaturated halogenated esters 1 N/A N/A N/A 0

Fluorinated ketones 1 0.11 - - 1

Fluorinated aldehydes 1 0.01 - - 1

Fluorotelomer alcohols 1 0.32 0.10 31% 4

Fluorinated GHGs with one or more carbon-iodine

bonds 1 0.4 - - 1

Other fluorinated compounds 110 112 177 159% 33

N/A = Not available

In addition, potential default GWPs for the fluorinated GHG groups were developed by also evaluating 

GWPs of the F-GHGs from AR5 only. This analysis can be found in Appendix B. 

 

3 The partial exception to this rule is the group of fully fluorinated GHGs. While the long atmospheric lifetimes of 

fully fluorinated GHGs give this group the highest average GWP of any group, those lifetimes are so long that 

differences between the lifetimes have relatively little impact on the differences between the 100-year GWPs of 

the fully fluorinated GHGs. Whether a fully fluorinated GHG has an atmospheric lifetime of 1,000 years or 2,000 

years, most emissions of that gas will still remain in the atmosphere after 100 years.
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 5

Figure 1 is a semi-log histogram that illustrates the number of chemicals in each F-GHG group or subgroup whose GWPs fall within different 

orders of magnitude. The left-most bar represents the number of compounds with GWPs between 0.001 and 0.01; the second bar represents 

compounds with GWPs between 0.01 and 0.1; etc. 

Figure 1. Histogram of F-GHG Group and Subgroup GWPs

0

5

10

15

20

25

30

35

40

45

50

0.001 to 0.01 0.01 to 0.1 0.1 to 1 1 to 10 10 to 100 100 to 1,000 1,000 to 10,000 10,000 and above

GWP

Fully Fluorinated GHGs

Saturated HFCs

Partially segregated HFEs and HCFEs

Non-segregated saturated HFEs and HCFEs

Unsaturated PFCs

Unsaturated HFCs and HCFCs

Unsaturated Halogenated Ethers

Unsaturated Halogenated Esters

Fluorinated Ketones

Fluorinated Aldehydes

Fluorotelomer Alcohols

Other Fluorinated GHGs
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 6

III. Comparison between Defaults and Estimated GWPs for Several FGHGs

ICF tested the accuracy of the default GWPs based on chemical groups by comparing the default GWPs 

to (1) the GWPs of F-GHGs with documented (but not peer-reviewed) GWPs provided by 3M and made 

available for comment through the April 5, 2013 Notice of Data Availability (NODA) (78 FR 20632) (Table 

4) and (2) the GWPs of F-GHGs with documented (but not peer-reviewed) GWPs in the Proposed 2013 

Revisions rule (Table 5). Chemical-specific GWPs for these fluorinated GHGs are not included in the 

Proposed Rule to Add GWPs. 

In Table 4, eight compounds with documented GWPs provided by 3M were categorized into the 

fluorinated GHG groups and assigned a default GWP:

 The first six compounds would be assigned to the “fully fluorinated GHGs” and have an average 

GWP of 9,452. This average GWP is similar to the suggested default GWP for “fully fluorinated 

GHGs”, which is equal to 10,000. 

 The remaining two compounds provided by 3M, HFE-7300 and HFE-7500, have an average GWP 

of 205. Both HFE-7300 and HFE-7500 are partially segregated saturated HFEs and have 

atmospheric lifetimes of 3.8 and 2.2 years, respectively. Therefore, these two compounds could 

be assigned to the partially segregated saturated HFEs and HCFEs, which has a suggested default 

GWP of 200. 

Table 4. 3M Company Fluorinated GHGs GWPs and Default GWP Comparison

Potential Fluorinated GHG 

Group

Chemical Designation or Common 

Name

Chemical 

Formula

3M 

Submitted 

GWP

Default 

GWP

Fully fluorinated GHGs Perfluorotripropyl amine (PTPA) C9F21N 8,690 10,000

Fully fluorinated GHGs Perfluorotributyl amine (PTBA) C12F27N 9,020 10,000

Fully fluorinated GHGs Perfluorotriamyl amine (PTAA) C15F33N 8,900 10,000

Fully fluorinated GHGs Perfluoromethyl morpholine (PMM) C5F11NO 9,500 10,000

Fully fluorinated GHGs Perfluoroisopropyl morpholine (PIPM) C7F15NO 11,000 10,000

Fully fluorinated GHGs 2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9-

hexadecafluorooxonane

C8F16O 9,600 10,000

Partially segregated saturated 

HFEs and HCFEs

1,1,1,2,2,3,4,5,5,5-decafluoro-3-

methoxy-4-trifluoromethyl-pentane 

(HFE-7300)

C7H3F13O 310 200

Partially segregated saturated 

HFEs and HCFEs

3-ethoxy-1,1,1,2,3,4,4,5,5,6,6,6-

dodecafluoro-2-trifluoromethyl-hexane

(HFE-7500)

C9H5F15O 100 200

As shown in Table 5, eleven compounds with documented (but not peer-reviewed) GWPs in the 

Proposed 2013 Revisions Rule that are not included in the Proposed Rule to Add GWPs were also 

categorized into the fluorinated GHG groups and assigned a default GWP:

 Two of the compounds that would be categorized as “unsaturated halogenated ethers”, which 

both had estimated GWPs of 3, would be assigned a default GWP of 1. 

 Six of the compounds that would be categorized as “fluorinated GHGs with one or more carboniodine bonds”, whose average estimated GWP was 2.3, would be assigned a default GWP of 1. 
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

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 The GWP for 1H,1H, 2H,2H-perfluorohexan-1-ol (42–AL) was listed as 2 in the Proposed 2013 

Revisions Rule; this compound would be categorized as a “fluorotelomer alcohol” and assigned a 

default GWP of 1. 

 The GWP for FK–6–1–12 was listed as 1 in the Proposed 2013 Revisions Rule and this compound 

would be categorized as a “fluorinated ketone” and assigned a default GWP of 1. 

 The GWP for carbonyl fluoride was listed as 2 in the 2013 Revisions Rule; this compound would 

be categorized as an “other fluorinated compound” and assigned a default GWP of 110.

With the exception of the default GWP for carbonyl fluoride, the default GWPs assigned to these 

compounds are quite close to their previously estimated GWPs. The defaults for the unsaturated 

compounds, fluorotelomer alcohols, and compounds with carbon-iodine bonds are lower than the

previously estimated GWPs for these compounds because the defaults reflect corrections made to the 

radiative efficiencies of these compounds in AR5. These corrections lower the radiative efficiencies to 

account for the fact that the compounds are very short-lived and are therefore not well-mixed in the 

atmosphere. 

Table 5. Fluorinated GHG GWPs in Proposed 2013 Revisions Rule Not Included in Newly Proposed Rule

Potential Fluorinated GHG 

Group

Chemical Designation or 

Common Name Chemical formula Proposed GWP

Default 

GWP

Unsaturated halogenated ethers Perfluoropropyl vinyl ether C5F10O 3 1

Unsaturated halogenated ethers Perfluoroethyl vinyl ether C4F8O 3 1

Fluorinated GHGs with one or 

more carbon-iodine bonds Perfluorethyl iodide (2–I) C2F5I 3 1

Fluorinated GHGs with one or 

more carbon-iodine bonds

Perfluorbutyl iodide (PFBI, 

42–I) C4F9I 3 1

Fluorinated GHGs with one or 

more carbon-iodine bonds Perfluorhexyl iodide (6–I) CF3CF2CF2CF2CF2CF2IC

6F13I

2 1

Fluorinated GHGs with one or 

more carbon-iodine bonds Perfluoroctyl iodide (8–I) C8F17I 2 1

Fluorinated GHGs with one or 

more carbon-iodine bonds

1,1,1,2,2-pentafluoro-4-

iodo butane (22–I) C4H4F5I 2 1

Fluorinated GHGs with one or 

more carbon-iodine bonds

1,1,1,2,2,3,3,4,4-

nonafluoro-6-iodo hexane 

(42– I)

C6H4F9I 2 1

Fluorotelomer alcohols

1H,1H, 2H,2Hperfluorohexan-1-ol (42–

AL)

C6H5F9O 5 1

Fluorinated ketones

FK–6–1–12/NovecTM 774, 

C7 Fluoroketone

C7F14O Chemical 

Blend 1 1

Other fluorinated compounds Carbonyl fluoride COF2 2 110

IV. Evaluation of Analysis Method by Dr. Wuebbles and 

Recommendations

Dr. Don Wuebbles evaluated the overall approach of assigning a default GWP to target compounds from 

certain compound groups based on the average GWP of similar “model” groups of compounds, and 

noted that although there are significant uncertainties associated with this approach due to the range of 

GWPs observed within each group of model compounds, this may be the most viable option for EPA 
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 8

based on the available information and time constraints. Dr. Wuebbles recommended developing a 

technique for assigning default GWPs based on modeling, or by developing a default estimate based on 

the relative amounts of fluorine, chlorine, and hydrogen in each compound. Both techniques would 

require additional research, and the technique based on modeling would be a major research effort. Dr. 

Wuebbles also suggested considering compounds with double carbon bonds (which are expected to all 

have short lifetimes) as a potential model group. Based on this suggestion, a model group consisting of

separate sub-groups for unsaturated PFCs, HFCs and HCFCs, halogenated ethers, and halogenated esters

was developed.4 Dr. Wuebbles also noted that the IPCC process for developing Assessment Reports 

(e.g., AR4) is not designed to be the sole arbiter of “official” GWP values, and other sources of published 

(i.e., peer-reviewed) literature (e.g., WMO, 2010) should be considered when establishing default GWP 

estimates. In addition, as a result of this discussion, numerical outliers are not excluded when 

calculating the suggested (i.e., average) model group GWP, since the GWPs for unknown target 

compounds might equally be outliers themselves.

Dr. Wuebbles also reviewed the comments that were received on the Proposed Amendments to Subpart 

L. Dr. Wuebbles agreed with the analyses conducted by DuPont because their suggestions are welldefined from a physical chemistry standpoint and also because Hodnebrog et al. 2013 is the proper 

source to use for such analyses as is it the basis for the GWPs presented in AR5. Dr. Wuebbles also noted 

that 3M’s suggestion to use the median GWP of a group of compounds (i.e., saturated HFEs) to assign a 

default GWP for that particular group is inappropriate, as the compounds with very high GWPs would be 

assigned a much smaller GWP value.

 

4 During a conference call on May 9, 2013 between ICF, EPA, and Dr. Don Wuebbles to have an intermediary 

discussion regarding the default GWP analysis, Dr. Wuebbles communicated that compounds with a lifetime 

greater than 1 year should be considered long-lived regardless of their corresponding GWP.
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 9

V. References

Derwent, R.G. 1995. Sources, Distributions, and Fates of VOCs in the Atmosphere. Issues in 

Environmental Science and Technology, 4. pp 1-16. 

Ellis, D.A. et al. 2003. Atmospheric Lifetime of Fluorotelomer Alcohols. Environmental Science & 

Technology. Vol 37. No. 17. pp 3816-3820.

Forster, P., V. Ramaswamy, P. Artaxo, T. Berntsen, R. Betts, D.W. Fahey, J. Haywood, J. Lean, D.C. Lowe, 

G. Myhre, J. Nganga, R. Prinn, G. Raga, M. Schulz and R. Van Dorland. 2007. Changes in Atmospheric 

Constituents and in Radiative Forcing. In: Climate Change 2007:The Physical Science Basis. Contribution 

of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change 

[Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M.Tignor and H.L. Miller (eds.)]. 

Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.

Hodnebrog, O. et al. 2013. Global Warming Potentials and Radiative Efficiencies of Halocarbons and 

Related Compounds: A Comprehensive Review. Reviews of Geophysics, 51. 

Hurley, M.D. et al. 2004. Atmospheric Chemistry of Fluorinated Alcohols:  Reaction with Cl Atoms and 

OH Radicals and Atmospheric Lifetimes. Journal of Physical Chemistry. Vol 108. No 11. pp 1973-1979.

IPCC/TEAP. 2005. Special Report: Safeguarding the Ozone Layer and the Global Climate System: Issues 

Related to Hydrofluorocarbons and Perfluorocarbons. Chapter 10: Non-Medical Aerosols, Solvents, and 

HFC-23. Available online at: http://www.ipcc.ch/pdf/special-reports/sroc/sroc10.pdf.

Myhre, G., D. Shindell, F.A. Breon, 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 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. 

Owens, J.G. 1999. “Segregated Hydrofluoroethers: Low GWP Alternatives to HFCs and PFCs,” 

Proceedings of the Joint Intergovernmental Panel on Climate Change/Technical and Economic 

Assessment Panel Expert Meeting on Options for the Limitation of Emissions of HFCs and PFCs: Petten, 

Netherlands.

Weubbles, Don. 2014. Transcribed Correspondence with Don Weubbles on March 14, 2014. 

Youn, D. et al. 2010. Potential impact of iodinated replacement compounds CF3I and CH3I on 

atmospheric ozone: a three-dimensional modeling study. Atmospheric Chemistry and Physics, 10. pp. 

10129-10144.

Young, C.J. et al. 2008. Atmospheric Chemistry of 4:2 Fluorotelomer Iodide (n-C4F9CH2CH2I): Kinetics and 

Products of Photolysis and Reaction with OH Radicals and Cl Atoms. Journal of Physical Chemistry. Vol 

112. No. 51. pp 13542-13548.
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

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Appendix A: F-GHGs by Fluorinated GHG Group 

Trade Name Chemical Designation or Common Name CAS No. Chemical Formula Proposed 

GWP GWP Source

Fully Fluorinated GHGs

PFPMIE perfluoropolymethylisopropyl ether 69991-67-9

CF3OCF(CF3)CF2OCF2O

CF3

10,300 AR4/Table A-1

PFC–14 Perfluoromethane 75–73–0 CF4 7,390 AR4/Table A-1

PFC–9–1–18 Perfluorodecalin (mixed) 306–94–5 C10F18 7,500 AR4/Table A-1

PFC–218 Perfluoropropane 76–19–7 C3F8 8,830 AR4/Table A-1

PFC–3–1–10 Perfluorobutane 355–25–9 C4F10 8,860 AR4/Table A-1

PFC–4–1–12 Perfluoropentane 678–26–2 C5F12 9,160 AR4/Table A-1

PFC–5–1–14 Tetradecafluorohexane 355–42–0 C6F14 9,300 AR4/Table A-1

PFC-6-1-12 Hexadecafluoroheptane 335-57-9 C7F16, CF3(CF2)5CF3 7,820 AR5

PFC-7-1-18 Octadecafluorooctane 307-34-6 C8F18, CF3(CF2)6CF3 7,620 AR5

PFC-318 Perfluorocyclobutane 115–25–3 c-C4F8 10,300 AR4/Table A-1

PFC–116 Perfluoroethane 76–16–4 C2F6 12,200 AR4/Table A-1

PFC–c216 Perfluorocyclopropane 931–91–9 c-C3F6 17,340 AR4/Table A-1

Perfluorodecalin (cis) 60433-11-6 cis-C10F18 7,240 AR5

Perfluorodecalin (trans) 60433-12-7 trans-C10F18 6,290 AR5

Trifluoromethyl sulphur pentafluoride 373–80–8 SF5CF3 17,700 AR4/Table A-1

Saturated HFCs

HFC–161 353–36–6 CH3CH2F 12 AR4/Table A-1

HFC–152 624–72–6 CH2FCH2F 53 AR4/Table A-1

HFC-263fb 1,1,1-Trifluoropropane 421-07-8 CH3CH2CF3 76 AR5

HFC–152a 75–37–6 CH3CHF2 124 AR4/Table A-1

HFC–41 593–53–3 CH3F 92 AR4/Table A-1

HFC-272ca 2,2-Difluoropropane 420-45-1 CH3CF2CH3 144 AR5

HFC-245eb 1,1,1,2,3-Pentafluoropropane 431-31-2 CH2FCHFCF3 290 AR5
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 11

Trade Name Chemical Designation or Common Name CAS No. Chemical Formula Proposed 

GWP GWP Source

HFC-245ea 1,1,2,3,3-Pentafluoropropane 24270-66-4 CHF2CHFCHF2 235 AR5

HFC–143 430–66–0 C2H3F3 353 AR4/Table A-1

HFC–32 75–10–5 CH2F2 675 AR4/Table A-1

HFC–245ca 679–86–7 C3H3F5 693 AR4/Table A-1

HFC–245fa 460–73–1 CHF2CH2CF3 1,030 AR4/Table A-1

HFC–365mfc 406–58–6 CH3CF2CH2CF3 794 AR4/Table A-1

HFC–134 359–35–3 CHF2CHF2 1,100 AR4/Table A-1

HFC–236ea 431–63–0 CHF2CHFCF3 1,370 AR4/Table A-1

HFC–236cb 677–56–5 CH2FCF2CF3 1,340 AR4/Table A-1

HFC–134a 811–97–2 CH2FCF3 1,430 AR4/Table A-1

HFC–43–

10mee 138495–42–8 CF3CFHCFHCF2CF3 1,640 AR4/Table A-1

HFC-227ca 1,1,1,2,2,3,3-Heptafluoropropane 2252-84-8 CF3CF2CHF2 2,640 AR5

HFC-329p 1,1,1,2,2,3,3,4,4-Nonafluorobutane 375-17-7 CHF2CF2CF2CF3 2,360 AR5

HFC–125 354–33–6 CHF2CF3 3,500 AR4/Table A-1

HFC–227ea 431–89–0 C3HF7 3,220 AR4/Table A-1

HFC-245cb 1,1,1,2,2-Pentafluoropropane 1814-88-6 CF3CF2CH3 4,620 AR5

HFC–143a 420–46–2 C2H3F3 4,470 AR4/Table A-1

HFC–236fa 690–39–1 C3H2F6 9,810 AR4/Table A-1

HFC–23 75–46–7 CHF3 14,800 AR4/Table A-1

Partially Segregated Saturated HFEs and HCFEs

R-E-143a; 

HFE-263m1 1,1,2,2-Tetrafluoro-1-(trifluoromethoxy)ethane 690-22-2 CF3OCH2CH3 29 AR5

HFE–

356mmz1 1,1,1,3,3,3-Hexafluoro-2-methoxypropane 13171-18-1 C4H4F6O 27 Table A-1
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 12

Trade Name Chemical Designation or Common Name CAS No. Chemical Formula Proposed 

GWP GWP Source

HFE-365mcf2 1-Ethoxy-1,1,2,2,2-pentafluoroethane 22052-81-9 CF3CF2OCH2CH3 58 AR5

HFE-569sf2, 

(HFE-7200) 

Isomer blend

1-Ethoxy-1,1,2,2,3,3,4,4,4-nonafluorobutane 163702-05-4 C4F9OC2H5 59 AR4/Table A-1

HG'-01 1,1,2,2-Tetrafluoro-1,2-dimethoxyethane 73287-23-7 CH3OCF2CF2OCH3 222 AR5

HG'-02 1,1,2,2-Tetrafluoro-1-methoxy-2-(1,1,2,2-tetrafluoro-2-

methoxyethoxy)ethane 485399-46-0 CH3O(CF2CF2O)2CH3 236 AR5

HG'-03 3,3,4,4,6,6,7,7,9,9,10,10-Dodecafluoro-2,5,8,11-

tetraoxadodecane 485399-48-2 CH3O(CF2CF2O)3CH3 221 AR5

HFE–245cb2 1,1,1,2,2-Pentafluoro-2-methoxy-ethane 22410-44-2 CF3CF2OCH3 708 AR4/Table A-1

HFE–

347mmy1 1,1,1,2,3,3,3-Heptafluoro-2-methoxypropane 22052–84–2 CH3OCF(CF3)2 343 Table A-1

HFE-449sl, 

(HFE-7100) 

Isomer blend

163702–07–6 C4F9OCH3 297 AR4/Table A-1

HFE–143a Trifluoromethoxymethane 421–14–7 CH3OCF3 756 AR4/Table A-1

HFE–

347mcc3 Heptafluoropropyl methyl ether 375-03-128523–86–6

CH3OCF2CF2CF3 575 AR4/Table A-1

1-Ethoxy-1,1,2,2,3,3,3-heptafluoropropane 22052-86-4 CF3CF2CF2OCH2CH3 61 AR5

2-Ethoxy-3,3,4,4,5-pentafluorotetrahydro-2,5-bis[1,2,2,2-

tetrafluoro-1-(trifluoromethyl)ethyl]-furan 920979-28-8 C12H5F19O2 56 AR5

HFE–

356mec3 1,1,1,2,3,3-Hexafluoro-3-methoxypropane 382-34-3 CH3OCF2CHFCF3 101 AR4/Table A-1

HFE–263fb2 1,1,1-Trifluoro-2-methoxyethane 460-43-5 CF3CH2OCH3 11 AR4/Table A-1

HFE–365mcf3 1,1,1,2,2-Pentafluoro-3-methoxypropane 378-16-5 CF3CF2CH2OCH3 11 AR4/Table A-1

HFE–356pcc3 1,1,2,2,3,3-Hexafluoro-1-methoxypropane 160620-20-2 CH3OCF2CF2CHF2 110 AR4/Table A-1

HFE–254cb1 1,1,2,2-Tetrafluoro-1-methoxyethane 425-88-7 CH3OCF2CHF2 359 AR4/Table A-1
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 13

Trade Name Chemical Designation or Common Name CAS No. Chemical Formula Proposed 

GWP GWP Source

HFE–374pc2 1-ethoxy-1,1,2,2-tetrafluoroethane 512–51–6 CH3CH2OCF2CHF2 557 AR4/Table A-1

1,1,2,2-Tetrafluoro-3-methoxy-propane; Methyl 2,2,3,3-

tetrafluoropropyl ether 60598-17-6 CHF2CF2CH2OCH3 0

AR5 (Precise GWP 

Calculated)

1-Ethoxy-1,1,2,3,3,3-hexafluoropropane 380-34-7 CF3CHFCF2OCH2CH3 23 AR5

Fluoro(methoxy)methane 460-22-0 CH3OCH2F 13 AR5

Difluoro(methoxy)methane 359-15-9 CH3OCHF2 144 AR5

2-Chloro-1,1,2-trifluoro-1-methoxyethane 425-87-6 CH3OCF2CHFCl 122 AR5

Non-segregated Saturated HFEs and HCFEs

HFE–356pcf2 1-(2,2-Difluoroethoxy)-1,1,2,2-tetrafluoroethane 50807-77-7 CHF2CH2OCF2CHF2 265 AR4/Table A-1

HFE–245fa1 1,1-Difluoro-2-(trifluoromethoxy)ethane 84011-15-4 CHF2CH2OCF3 286 AR4/Table A-1

Sevoflurane 

(HFE347mmz1)2-(Difluoromethoxy)-1,1,1,3,3,3-hexafluoropropane 28523-86-6 (CF3)2CHOCHF2 216 AR5

Isoflurane 

(HCFE–

235da2)

2-chloro-2-(difluoromethoxy)-1,1,1-trifluoro-ethane 26675-46-7 C3H2ClF5O 350 AR4/Table A-1

HFE–338mcf2 1,1,1,2,2-Pentafluoro-2-(2,2,2-trifluoroethoxy)ethane 156053-88-2 CF3CH2OCF2CF3 552 AR4/Table A-1

HFE–347mcf2 1-(2,2-Difluoroethoxy)-1,1,2,2,2-pentafluoroethane 171182-95-9 CHF2CH2OCF2CF3 374 AR4/Table A-1

HFE–356pcf3 3-(difluoromethoxy)-1,1,2,2-tetrafluoropropane 35042–99–0 CHF2OCH2CF2CHF2 502 AR4/Table A-1

HFE–236fa 1,1,1-Trifluoro-2-(trifluoromethoxy)ethane 20193–67–3 CF3CH2OCF3 487 AR4/Table A-1

HFE-356mff2 BIS(2,2,2-TRIFLUOROETHYL) ETHER 333-36-8 CF3CH2OCH2CF3 17 AR5

HFE–245fa2 2-(Difluoromethoxy)-1,1,1-trifluoroethane 1885-48-9 CHF2OCH2CF3 659 AR4/Table A-1

Desflurane 

(HFE–

236ea2)

2-(Difluoromethoxy)-1,1,1,2-tetrafluoroethane 57041-67-5 CHF2OCHFCF3 989 AR4/Table A-1
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 14

Trade Name Chemical Designation or Common Name CAS No. Chemical Formula Proposed 

GWP GWP Source

HFE–

338pcc13 

(HG–01)

1,2-Bis(difluoromethoxy)-1,1,2,2-tetrafluoroethane 188690–78–0 CHF2OCF2CF2OCHF2 1,500 AR4/Table A-1

HFE–43–

10pccc (H–

Galden 

1040x)

1-(Difluoromethoxy)-2-

[(difluoromethoxy)(difluoro)methoxy]-1,1,2,2-

tetrafluoroethane

E1730133 CHF2OCF2OC2F4OCHF2 1,870 AR4/Table A-1

HFE–

329mcc2 1,1,1,2,2-Pentafluoro-2-(1,1,2,2-tetrafluoroethoxy)ethane 134769-21-4 CHF2CF2OCF2CF3 919 AR4/Table A-1

HFE–347pcf2 1,1,2,2-Tetrafluoro-1-(2,2,2-trifluoroethoxy)ethane 406-78-0 CHF2CF2OCH2CF3 580 AR4/Table A-1

HFE–227ea 2356–62–9 CF3CHFOCF3 1,540 AR4/Table A-1

HFE–236ca12 

(HG–10) Bis(difluoromethoxy)difluoromethane 78522-47-1 CHF2OCF2OCHF2 2,800 AR4/Table A-1

HG-02 1-(Difluoromethoxy)-2-(2-(difluoromethoxy)-1,1,2,2-

tetrafluoroethoxy)-1,1,2,2-tetrafluoroethane 205367-61-9

HF2C-(OCF2CF2)2-

OCF2H

2,730 AR5

HG-03 1,1,3,3,4,4,6,6,7,7,9,9,10,10,12,12-Hexadecafluoro2,5,8,11-tetraoxadodecane 173350-37-3

HF2C-(OCF2CF2)3-

OCF2H

2,850 AR5

HG-21 1,1,3,3,5,5,7,7,8,8,10,10-Dodecafluoro-2,4,6,9-

tetraoxadecane 249932-26-1

HF2COCF2CF2OCF2OCF2OCF2H

3,890 AR5

1,1,2,2-Tetrafluoro-1-(fluoromethoxy)ethane 37031-31-5 CH2FOCF2CF2H 871 AR5

1,1,2-Trifluoro-2-(trifluoromethoxy)-ethane 84011-06-3 CHF2CHFOCF3 1,240 AR5

Fluoro(fluoromethoxy)methane 462-51-1 CH2FOCH2F 130 AR5

Difluoro(fluoromethoxy)methane 461-63-2 CH2FOCHF2 617 AR5

Trifluoro(fluoromethoxy)methane 2261-01-0 CH2FOCF3 751 AR5

HCFE-235ca2 

(enflurane) 2-Chloro-1-(difluoromethoxy)-1,1,2-trifluoroethane 13838-16-9 CHF2OCF2CHFCl 583 AR5

HFE–

338mmz1 2-(Difluoromethoxy)-1,1,1,3,3,3-hexafluoropropane 26103-08-2 (CF3)2CHOCHF2 380 AR4/Table A-1
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 15

Trade Name Chemical Designation or Common Name CAS No. Chemical Formula Proposed 

GWP GWP Source

HFE-236ca 1-(Difluoromethoxy)-1,1,2,2-tetrafluoroethane 32778-11-3 CHF2OCF2CHF2 4,240 AR5

HFE–134 1691–17–4 CHF2OCHF2 6,320 AR4/Table A-1

HFE-329me3 1,1,1,2,3,3-Hexafluoro-3-(trifluoromethoxy)propane 428454-68-6 CF3CFHCF2OCF3 4,550 AR5

HFE–125 (difluoromethoxy)(trifluoro)methane 3822–68–2 CHF2OCF3 14,900 AR4/Table A-1

HG-20 (Difluoromethoxy)((difluoromethoxy)difluoromethoxy)diflu

oromethane 249932-25-0 HF2C-(OCF2)2-OCF2H 5,300 AR5

HG-30 1,1,3,3,5,5,7,7,9,9-Decafluoro-2,4,6,8-tetraoxanonane 188690-77-9 HF2C-(OCF2)3-OCF2H 7,330 AR5

1,1,1,2,2,3,3-Heptafluoro-3-(1,2,2,2-tetrafluoroethoxy)-

propane

3330-15-2 CF3CF2CF2OCHFCF3 6,490 AR5

1,1'-Oxybis[2-(difluoromethoxy)-1,1,2,2-tetrafluoroethane 205367-61-9 HCF2O(CF2CF2O)2CF2H 4,920 AR5

1,1,3,3,4,4,6,6,7,7,9,9,10,10,12,12-hexadecafluoro2,5,8,11-Tetraoxadodecane 173350-37-3 HCF2O(CF2CF2O)3CF2H 4,490 AR5

1,1,3,3,4,4,6,6,7,7,9,9,10,10,12,12,13,13,15,15-

eicosafluoro-2,5,8,11,14-Pentaoxapentadecane 173350-38-4 HCF2O(CF2CF2O)4CF2H 3,630 AR5

Unsaturated PFCs

PFC C-1418 Perfluorocyclopentene; Octafluorocyclopentene 559-40-0 c-C5F8 1.97 AR5

Dyneon HFP 

(3M) hexafluoropropylene (HFP); PFC-1216; Perfluoropropene 116-15-4 C3F6 , CF3CF=CF2 0.05 AR5 (Precise GWP Calculated)

TFE tetrafluoroethylene (TFE); PFC-1114; Perfluoroethene 116-14-3 CF2=CF2, C2F4; 0.004 AR5 (Precise GWP 

Calculated)

Perfluorobuta-1,3-diene 685-63-2 CF2=CFCF=CF2 0.003 AR5 (Precise GWP 

Calculated)

Perfluorobut-1-ene 357-26-6 CF3CF2CF=CF2 0.10 AR5 (Precise GWP 

Calculated)

Perfluorobut-2-ene 360-89-4 CF3CF=CFCF3 1.82 AR5 (Precise GWP 

Calculated)
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 16

Trade Name Chemical Designation or Common Name CAS No. Chemical Formula Proposed 

GWP GWP Source

Unsaturated HFCs

HFC1234ze(Z) (Z)-1,3,3,3-Tetrafluoroprop-1-ene 29118-25-0

C3H2F4

trans-CF3CH=CHF, 

CF3CH=CHF(Z)

0.29 AR5 (Precise GWP 

Calculated)

HFC1234ze(E) (E)-1,3,3,3-Tetrafluoroprop-1-ene 1645-83-6C3H2F4

cis-CF3CH=CHF 0.97 AR5 (Precise GWP Calculated)

TFP trifluoro propene (TFP); HFC-1243zf; 3,3,3-Trifluoroprop-1-

ene

677-21-4 C3H3F3 , CF3CH=CH2 0.12 AR5 (Precise GWP 

Calculated)

VF vinyl fluoride (VF); HFC-1141 75-02-5 C2H3F, CH2=CHF 0.02 AR5 (Precise GWP 

Calculated)

VF2 vinylidiene fluoride (VF2); HFC-1132a 75-38-7 C2H2F2 , CF2=CH2 0.04 AR5 (Precise GWP 

Calculated)

HFC-1234yf; 

HFO-1234yf 2,3,3,3-Tetrafluoroprop-1-ene 754-12-1

C3H2F4 

CF3CF=CH2

0.31 AR5 (Precise GWP 

Calculated)

Capstone 42-

U

perfluorobutyl ethene (42-U); 3,3,4,4,5,5,6,6,6-

Nonafluorohex-1-ene

19430-93-4

C6H3F9, 

CF3(CF2)3CH=CH2

0.16 AR5 (Precise GWP 

Calculated)

Capstone 62-

U

perfluorohexyl ethene (62-U); 3,3,4,4,5,5,6,6,7,7,8,8,8-

Tridecafluorooct-1-ene

25291-17-2

C8H3F13, 

CF3(CF2)5CH=CH2

0.11 AR5 (Precise GWP 

Calculated)

Capstone 82-

U

perfluorooctyl ethene (82-U); 

3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-Heptadecafluorodec-1-

ene

21652-58-4

C10H3F17, 

CF3(CF2)7CH=CH2

0.09 AR5 (Precise GWP 

Calculated)

Solstice 1233 

zd(E) trans-1-chloro-3,3,3-trifluoroprop-1-ene 102687-65-0 C3H2ClF3, CHCl=CHCF3 1.34 AR5 (Precise GWP Calculated)

(E)-HFC1225ye (E)-1,2,3,3,3-Pentafluoroprop-1-ene 5595-10-8 CF3CF=CHF(E) 0.06 AR5 (Precise GWP 

Calculated)

(Z)-HFC1225ye (Z)-1,2,3,3,3-Pentafluoroprop-1-ene 5528-43-8 CF3CF=CHF(Z) 0.22 AR5 (Precise GWP 

Calculated)

HFO-1345zfc 3,3,4,4,4-Pentafluorobut-1-ene 374-27-6 C2F5CH=CH2 0.09 AR5 (Precise GWP 

Calculated)

(Z)-HFC-1336 (Z)-1,1,1,4,4,4-Hexafluorobut-2-ene 692-49-9 CF3CH=CHCF3(Z) 1.58 AR5 (Precise GWP 

Calculated)
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 17

Trade Name Chemical Designation or Common Name CAS No. Chemical Formula Proposed 

GWP GWP Source

PMVE, HFE216 perfluoromethyl vinyl ether (PMVE) 1187-93-5 CF3OCF=CF2 0.17 AR5 (Precise GWP 

Calculated)

Fluoroxene (2,2,2-Trifluoroethoxy)ethene 406-90-6 CF3CH2OCH=CH2 0.05 AR5 (Precise GWP 

Calculated)

Fluorinated Aldehydes

3,3,3-Trifluoro-propanal 460-40-2 CF3CH2CHO 0.01 AR5 (Precise GWP 

Calculated)

Fluorinated Ketones

Novec 1230 FK-5-1-12 Perfluoroketone; FK-5-1-12myy2; PERFLUORO(2-

METHYL-3-PENTANONE) 756-13-8 CF3CF2C(O)CF(CF3)2 0.1 AR5 (Precise GWP Calculated)

Fluorotelomer Alcohols

3,3,3-Trifluoropropan-1-ol 2240-88-2 CF3CH2CH2OH 0.35 AR5 (Precise GWP 

Calculated)

3,3,4,4,5,5,6,6,7,7,7-Undecafluoroheptan-1-ol 185689-57-0 CF3(CF2)4CH2CH2OH 0.43 AR5

3,3,4,4,5,5,6,6,7,7,8,8,9,9,9-Pentadecafluorononan-1-ol 755-02-2 CF3(CF2)6CH2CH2OH 0.33 AR5

3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,11-

Nonadecafluoroundecan-1-ol 87017-97-8 CF3(CF2)8CH2CH2OH 0.19 AR5

Fluorinated GHGs with one or more carbon-iodine bonds

Trifluoroiodomethane 2314-97-8 CF3I 0.4 AR4

Other Fluorinated Compounds

Perfluorobutyl acetate 209597-28-4 CH3COOCF2CF2CF2CF3 1.6 AR5 (Precise GWP 

Calculated)

Perfluoropropyl acetate 1344118-10-0 CH3COOCF2CF2CF3 1.8 AR5 (Precise GWP 

Calculated)

Perfluoroethyl acetate 343269-97-6 CH3COOCF2CF3 2.1 AR5 (Precise GWP 

Calculated)

Trifluoromethyl acetate 74123-20-9 CH3COOCF3 2.0 AR5 (Precise GWP 

Calculated)

1,1-Difluoroethyl 2,2,2-trifluoroacetate 1344118-13-3 CF3COOCF2CH3 31 AR5
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 18

Trade Name Chemical Designation or Common Name CAS No. Chemical Formula Proposed 

GWP GWP Source

Ethyl 2,2,2-trifluoroacetate 383-63-1 CF3COOCH2CH3 1.30 AR5

2,2,2-Trifluoroethyl 2,2,2-trifluoroacetate 407-38-5 CF3COOCH2CF3 7 AR5

Methyl 2,2-difluoroacetate 433-53-4 HCF2COOCH3 3 AR5

Difluoromethyl 2,2,2-trifluoroacetate 2024-86-4 CF3COOCHF2 27 AR5

Methyl 2,2,2-trifluoroacetate 431-47-0 CF3COOCH3 52 AR5

2,2,3,3,4,4,5,5-Octafluorocyclopentanol 16621-87-7 -(CF2)4CH(OH)- 73 AR4/Table A-1

1,1,1,3,3,3-Hexafluoropropan-2-ol 920-66-1 (CF3)2CHOH 182 AR5

2,2,3,3,3-Pentafluoropropan-1-ol 422-05-9 CF3CF2CH2OH 19 AR5

4,4,4-Trifluorobutan-1-ol 461-18-7 CF3(CH2)2CH2OH 0.05 AR5 (Precise GWP 

Calculated)

2,2,3,3,4,4,4-Heptafluorobutan-1-ol 375-01-9 C3F7CH2OH 34 AR5

2,2,3,3-Tetrafluoro-1-propanol 76-37-9 CHF2CF2CH2OH 13 AR5

2,2,3,4,4,4-Hexafluoro-1-butanol 382-31-0 CF3CHFCF2CH2OH 17 AR5

2,2,3,3,4,4,4-Heptafluoro-1-butanol 375-01-9 CF3CF2CF2CH2OH 16 AR5

2-Fluoroethanol 371-62-0 CH2FCH2OH 1.07 AR5 (Precise GWP 

Calculated)

2,2-Difluoroethanol 359-13-7 CHF2CH2OH 3 AR5

2,2,2-Trifluoroethanol 75-89-8 CF3CH2OH 20 AR5

Methyl carbonofluoridate 1538-06-3 FCOOCH3 95 AR5

1,1-Difluoroethyl carbonofluoridate 1344118-11-1 FCOOCF2CH3 27 AR5

Trifluoromethyl formate 85358-65-2 HCOOCF3 588 AR5

Perfluoroethyl formate 313064-40-3 HCOOCF2CF3 580 AR5

Perfluoropropyl formate 271257-42-2 HCOOCF2CF2CF3 376 AR5

Perfluorobutyl formate 197218-56-7 HCOOCF2CF2CF2CF3 392 AR5

2,2,2-Trifluoroethyl formate 32042-38-9 HCOOCH2CF3 33 AR5
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 19

Trade Name Chemical Designation or Common Name CAS No. Chemical Formula Proposed 

GWP GWP Source

3,3,3-Trifluoropropyl formate 1344118-09-7 HCOOCH2CH2CF3 17 AR5

1,2,2,2-Tetrafluoroethyl formate 481631-19-0 HCOOCHFCF3 470 AR5

1,1,1,3,3,3-Hexafluoropropan-2-yl formate 856766-70-6 HCOOCH(CF3)2 333 AR5

Halon-1202 Dibromodifluoromethane 75-61-6 CBR2F2 231 AR5

Halon-2311 / 

Halothane 2-Bromo-2-chloro-1,1,1-trifluoroethane 151-67-7 CHBrClCF3 41 AR5
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 20

Appendix B: Default GWPs Based on AR5 GWPs

As indicated in Section II, potential default GWPs for the fluorinated GHG groups were developed using

the GWPs of the F-GHGs from AR5 only. Table 6, below, presents the new fluorinated GHG groups with 

the corresponding average, standard deviation, and relative standard deviation of the GWPs for each 

group.

Table 6. Average, Standard Deviation, and Relative Standard Deviation of GWPs from AR5 Only of 

Fluorinated GHG Groups for Newly Proposed Rule 

Fluorinated GHG Group Average 

GWP 

Standard 

Deviation

Relative 

Standard 

Deviation

Possible 

Default

GWP

Fully fluorinated GHGs 8,953 2,671 30% 9,000

Saturated hydrofluorocarbons (HFCs) 2,016 2,848 141% 2,000

Partially segregated saturated HFEs and HCFEs 207 204 99% 210

Non-segregated saturated HFEs and HCFEs 2,728 2,619 96% 2,700

Unsaturated PFCs 0.66 0.96 146% 1

Unsaturated HFCs and unsaturated HCFCs 0.38 0.51 134% 1

Unsaturated halogenated ethers 0.11 - - 1

Unsaturated halogenated esters N/A N/A N/A 1

Fluorinated ketones 0.11 - - 1

Fluorinated aldehydes 0.01 - - 1

Fluorotelomer alcohols 0.32 0.10 31% 1

Fluorinated GHGs with one or more carbon-iodine bonds 0.4 - - 1

Other fluorinated compounds 111 178 162% 110
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 21

Appendix C: Evaluation of Default GWPs Considering Numerical and 

Chemical Outliers

The eight main model groups were further evaluated without numerical outliers and the fully 

fluorinated GHGs were further evaluated including chemical outliers. For the purpose of this analysis, 

numerical outliers were defined as compounds with a GWP greater than or less than two standard 

deviations from the average model group GWP. Table 7 presents the proposed fluorinated GHG groups 

excluding outliers with the corresponding average, standard deviation, and relative standard deviation 

of the GWPs for each group. As expected, exclusion of numerical outliers moves the average GWP away 

from the GWPs of the outliers and reduces the absolute and relative standard deviations of the GWPs 

within the model groups.

Table 7. Average, Standard Deviation, and Relative Standard Deviation of GWPs of Fluorinated GHG 

Groups Excluding Numerical Outliers 

Fluorinated GHG Group Excluding Outliers Proposed 

GWP

Average 

GWP

Standard 

Deviation

Relative 

Standard 

Deviation

Number 

of 

Chemicals 

in Group

Fully fluorinated GHGs 10,000 8,678 1,608 19% 13

Saturated HFCs 2,200 1,344 1,409 105% 24

Partially segregated HFEs and HCFEs 200 158 227 144% 23

Non-segregated saturated HFEs and HCFEs 2,400 2,089 488 23% 36

Unsaturated PFCs 1 0.66 0.96 146% 6

Unsaturated HFCs 1 0.29 0.40 136% 13

Unsaturated halogenated ethers 1 0.11 0.09 79% 2

Unsaturated halogenated esters 1 N/A N/A N/A 0

Fluorinated ketones 1 N/A N/A N/A 0

Fluorinated aldehydes 1 N/A N/A N/A 0

Fluorotelomer alcohols 1 0.32 0.10 31% 4

Fluorinated GHGs with one or more carboniodine bonds 1 N/A N/A N/A 0

Other fluorinated GHGs 110 68 114 167% 30

Only one model group, fully fluorinated GHGs, has the potential to include compounds that are 

chemically different from the compounds whose GWPs are being modeled by that group. These 

compounds, SF6 and NF3, are excluded from fully fluorinated GHGs in the main analysis. Table 8 shows 

how the average GWP for this group would increase if SF6 and NF3 were included in the group.

Table 8. Average, Standard Deviation, and Relative Standard Deviation of GWPs of Fully Fluorinated 

GHG Group, Including SF6 and NF3

Fluorinated GHG Group Proposed 

GWP

Average 

GWP

Standard 

Deviation

Relative 

Standard 

Deviation

Number 

of 

Chemicals 

in Group

Fully fluorinated GHGs, Including SF6 and NF3 10,000 11,050 4,769 43% 17
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 22

Appendix D: Evaluation of the Comments Received on the Proposed 

Amendments to Subpart L 

Comments related to the construction of the F-GHG groups were received from three entities: DuPont, 

3M Company, and ACC. These commenters provided suggestions to improve the default GWPs 

presented in the Proposed Amendments to Subpart L.

ICF evaluated whether the suggestions provided by DuPont, 3M, and ACC5—to add compounds to the 

existing groups and to create new groups—were likely to improve the accuracy and precision of the

default GWPs proposed for subpart L. To do this evaluation, ICF incorporated these suggestions into the 

analysis used to develop the default GWPs for the Proposed Amendments to Subpart L. Specifically, ICF 

analyzed the “other fluorinated compounds” and “saturated HFEs and HCFEs” groups from the Proposed 

Amendments to Subpart L and assigned each compound a more specific group designation. By 

disaggregating the “other fluorinated compounds” into these groups (e.g., unsaturated halogenated 

esters, fluorinated aldehydes, fluorotelomer alcohols, fluorinated alcohols, formates, etc.), it was 

possible to evaluate the GWPs of each group and compare them to the previously proposed GWP of 100 

(see Table 1). A similar approach was adopted for the compounds in the proposed group “saturated 

HFEs and HCFEs.”

Table 9 presents a comparison of the Proposed Amendments to Subpart L’s F-GHG groups and the 

commenters’ suggested F-GHG groups. In most cases, the F-GHG compounds in the suggested new 

groups were originally part of the “other fluorinated compounds” group in the Proposed Amendments 

to Subpart L; the exceptions were the compounds in the suggested new groups, “partially segregated 

saturated HFEs” and “non-segregated saturated HFEs,” which were originally part of the “saturated HFEs 

and HCFEs” group.

Table 9. Comparison of Proposed Amendments to Subpart L and Commenter Suggested F-GHG 

Groupsa

Source Fluorinated GHG Group

GWP 

Suggested 

by Source 

(100-year)

Number 

of 

Chemicals 

in Group

Average 

GWP

(100-

year)

Average 

Lifetime 

(years)

Proposed 

Amendments 

to Subpart L

Fully fluorinated GHGs 10,000 15 9,857 5,953

Saturated hydrofluorocarbons (HFCs) 2,200 26 2,187 32

Saturated hydrofluoroethers (HFEs) and 

saturated hydrochlorofluoroethers (HCFEs) 1,600 61 1,536 10

Unsaturated PFCs, unsaturated HFCs, 

unsaturated HCFCs, unsaturated HFEs, and 

fluorinated ketones

1 23 <1 «1b

Other fluorinated compounds 100 32 94 <1

Recommended 

by DuPont

Unsaturated PFCs, unsaturated HFCs, 

unsaturated HCFCs, unsaturated 

halogenated ethers, unsaturated 

halogenated esters, fluorinated ketones, 

and fluorinated aldehydes

1 25 <1 «1b

 

5

ICF did not specifically address comments provided by ACC because their suggested groups were covered by 

DuPont’s recommendations, and because the groups suggested by DuPont were more specific.
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 23

Source Fluorinated GHG Group

GWP 

Suggested 

by Source 

(100-year)

Number 

of 

Chemicals 

in Group

Average 

GWP

(100-

year)

Average 

Lifetime 

(years)

Fluorinated and Fluorotelomer Alcoholsc 1 15 25 <1

Fluorotelomer Alcoholsd 1 4 <1 «1

Fluorinated GHGs with one or more carboniodine bonds 1 0 N/A N/A

Recommended 

by 3M

Partially segregated saturated HFEs 230 25 204 2

Non-segregated saturated HFEs 2,800 37 2,436 15

Evaluated by 

ICF

Other fluorinated compounds without fully 

fluorinated unsaturated halogenated ethers, 

fluorinated aldehydes, fluorotelomer 

alcohols, or fluorinated GHGs with carboniodine bonds

110 33 112 1

Evaluated by 

ICF Formates 350 8 349 3

Evaluated by 

ICF

Other fluorinated compounds without fully 

fluorinated unsaturated halogenated ethers, 

fluorinated aldehydes, fluorotelomer 

alcohols, fluorinated GHGs with carboniodine bonds, or formates

20 21 19 <1

a DuPont also recommended grouping 4,4,4-trifluorobutanal (a fluorinated aldehyde) with the fluorinated ketones and vinyl 

2,2,2-trifluoroacetate (an unsaturated ester) with the unsaturated halogenated ethers. 4,4,4-trifluorobutanal and vinyl 2,2,2-

trifluoroacetate are included in the AR5 Comprehensive Review, but were ultimately not published in AR5 because they do not 

have GWPs and are therefore not included in this analysis.

b An average lifetime of «1 denotes a value less than or equal to 1 x 10-2

. 

c

Includes four fluorotelomer alcohols.

d Fluorotelomer alcohols, a subset of fluorinated alcohols, were evaluated separately.

a. Unsaturated Halogenated Ethers

DuPont suggested broadening “unsaturated HFEs” to “unsaturated halogenated ethers” to account for 

the carbon-carbon double bond in unsaturated ethers that results in a short atmospheric lifetime and 

low GWP for these compounds. As explained by DuPont, the degree of fluorination of the compound has 

a small effect on the lifetime and GWP. For example, HFE-216 (CF3OCF=CF2), an unsaturated fully 

fluorinated ether, has a 100-year GWP of 0.176 and lifetime of 8.4 days in IPCC AR5. Additionally, 

fluoroxene (CF3CH2OCH=CH2), an unsaturated ether that is not fully fluorinated, has a 100-year GWP of 

and lifetime of 3.6 days according to IPCC AR5. This suggestion revises the classification of all 

unsaturated fully fluorinated ethers, which were previously assigned as “other fluorinated compounds,” 

instead of unsaturated HFEs, because they do not contain a carbon-hydrogen bond. In the revised 

fluorinated GHG group, all “unsaturated halogenated ethers” must contain one or more carbon-carbon 

multiple bonds, but can have any degree of fluorine or chlorine substitution in the alkyl groups. ICF 

expects this categorization to be accurate and to appropriately categorize all unsaturated fluorinated 

ethers, regardless of the degree of fluorination and/or chlorination in the alkyl groups.

 

6

This precise GWP was calculated using the atmospheric lifetime and the corrected radiative efficiency provided in the AR5.
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 24

b. Fluorinated Ketones and Aldehydes

DuPont suggested expanding fluorinated ketones to include fluorinated aldehydes, which were 

previously categorized as “other fluorinated compounds;” this would assign fluorinated aldehydes a 

GWP of 1. This approach is accurate and well defined from a physical chemistry viewpoint. As noted by 

DuPont, peer-reviewed literature suggests similarities between the behavior of fluorinated ketones and 

aldehydes as they photodissociate readily in hours or days. Photolysis lifetimes of aldehydes and 

ketones in the sunlit troposphere are approximately several days (Derwent, 1995). This behavior 

indicates that these compounds have short atmospheric lifetime and therefore low GWPs. 

For example, 3,3,3 –trifluoro-propanal has a 100-year GWP of 0.017 and lifetime of 2.0 days according to 

IPCC AR5. ICF’s evaluation shows that this group could be added to the previously existing group of 

compounds assigned a GWP of 1 (see Table 9). ICF expects this categorization to be accurate for the 

fluorinated aldehydes whose atmospheric behavior has not yet been studied.

c. Fluorinated Alcohols (including Fluorotelomer Alcohols)

DuPont suggested that all fluorinated alcohols be assigned a GWP of 1 based on their analysis of the 

GWPs of a subset of fluorinated alcohols, fluorotelomer alcohols. DuPont noted that all fluorotelomer 

alcohols are likely to have short atmospheric lifetimes and therefore low GWPs. A study of the kinetics 

of the reactions of fluorotelomer alcohols with OH radicals indicates that the atmospheric lifetime of 

fluorotelomer alcohols, regardless of the length of the molecule, is approximately 20 days, or 0.05 years 

(Ellis et al., 2003). Additionally, IPCC AR5 assigns GWPs of less than one to all four of the fluorotelomer 

alcohols included in AR5. For example, 3,3,3-trifluoropropan-1-ol has a GWP of 0.357 and an 

atmospheric lifetime of 12.0 days and 3,3,4,4,5,5,6,6,7,7,7-Undecafluoroheptan-1-ol has a GWP of 0.437

and an atmospheric lifetime of 20.0 days; both of these compounds are fluorotelomer alcohols. 

DuPont’s comments recommend combining fluorotelomer alcohols and fluorinated alcohols into a single 

group with an assigned GWP of 1. However, as shown in Table 9 above, the average GWP of fluorinated

alcohols, including the four fluorotelomer alcohols, is greater than 1 (i.e., 25), and therefore assigning all 

fluorinated alcohols a GWP of 1 is not accurate. Additionally, a study of the kinetics of the reactions of a 

series of fluorinated alcohols with OH radicals indicates that the atmospheric lifetime of fluorinated 

alcohols is approximately 164 days, or 0.45 years (Hurley et al., 2004). ICF’s analysis suggests assigning 

fluorotelomer alcohols a GWP of 1 and adding them to the previously existing group of compounds 

assigned a GWP of 1, while other fluorinated alcohols would remain in the “other fluorinated 

compounds” group.

d. Unsaturated Halogenated Esters

DuPont suggested assigning unsaturated halogenated esters, which were previously categorized as 

“other fluorinated compounds,” a GWP of 1. This approach is accurate and well defined from a physical 

chemistry viewpoint. As described by DuPont, unsaturated halogenated esters have a double carboncarbon bond whose reactivity results in a short atmospheric lifetime and therefore low GWP. 

A search of the peer-reviewed literature, including AR5 and Hodnebrog et al. (2013), did not yield GWPs 

for any unsaturated halogenated esters. Hodnebrog et al. (2013) includes a radiative efficiency, but not 

an atmospheric lifetime, for one unsaturated halogenated ester, vinyl, 2,2,2-trifluoroacetate. This 

radiative efficiency, 0.387 Wm-2ppb-1, is an overestimate because it has not been corrected to reflect the 

 

7

This precise GWP was calculated using the atmospheric lifetime and the corrected radiative efficiency provided in the AR5.
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 25

(probably very short) atmospheric lifetime of vinyl, 2,2,2-trifluoroacetate.8 Nevertheless, when this 

uncorrected radiative efficiency is considered in conjunction with the atmospheric behavior of a 

saturated near-relative of vinyl, 2,2,2-trifluoroacetate, ethyl 2,2,2-trifluoroacetate, some conclusions 

may be drawn regarding the GWP of the former. 

According to AR5, ethyl 2,2,2-trifluoroacetate has a lifetime of 21.9 days, a corrected radiative efficiency 

of 0.053, and a GWP of 1.3.

9 Hodnebrog et al. (2013) provides an uncorrected radiative efficiency of 0.28

Wm-2ppb-1for ethyl 2,2,2,-trifluoroacetate, indicating that the correction factor for this compound (and 

compounds with similar atmospheric lifetimes) is about 0.19. Assuming vinyl 2,2,2-trifluoroacetate has 

a lifetime of no more than 21.9 days and that the same correction factor should be applied to its 

radiative efficiency, the GWP for vinyl 2,2,2-trifluoroacetate is estimated to be 1.8. Because vinyl 2,2,2-

trifluoroacetate is unsaturated, it is likely to be more short-lived than ethyl 2,2,2-trifluoroacetate and 

therefore to have a lower GWP than what was calculated using a lifetime of 21.9 days. For this 

compound to have a GWP of around 1 (applying the same corrected radiative efficiency), its

atmospheric lifetime would have to be approximately 12 days. This is comparable to the average 

atmospheric lifetimes of the unsaturated HFCs and PFCs (10 and 13 days, respectively). 

Looking beyond vinyl 2,2,2-trifluoroacetate, the atmospheric behavior of the saturated and unsaturated 

HFCs and PFCs implies that the atmospheric lifetimes and GWPs of unsaturated fluorinated esters are 

likely to be low. Specifically, the saturated HFCs and PFCs have average GWPs of 2,187 and 9,857

respectively, considerably higher than the average GWP of the saturated fluorinated esters, 162. This 

difference is largely driven by the difference in atmospheric lifetimes, with HFCs and PFCs having 

average lifetimes of 32 and 5,953 years, respectively, and saturated fluorinated esters having an average 

lifetime of 1.2years. At the same time, the unsaturated HFCs and PFCs have average GWPs of 0.4 and 

0.7 respectively, reflecting atmospheric lifetimes of days or weeks. Because unsaturated fluorinated 

esters are expected to have lifetimes as brief (or briefer) than those of HFCs and PFCs, the unsaturated 

fluorinated esters are also likely to have GWPs below 1. 

This conclusion is expected to be valid as long as the other compound-dependent term in the GWP 

calculation, specifically, the ratio of radiative efficiency to molecular weight, is also similar for 

unsaturated esters and unsaturated HFCs and PFCs. To further investigate the latter assumption, ICF 

calculated the ratio of the uncorrected radiative efficiency (RE) to the molecular weight (MW) (i.e., 

RE/MW) for all of the saturated and unsaturated fluorinated esters, HFCs, and PFCs that are included in 

the default GWP analysis.10 This exercise evaluated the possibility that the fluorinated esters have 

significantly higher RE/MW ratios than the HFCs and PFCs, which would indicate that even if the 

unsaturated esters are as short-lived as the unsaturated HFCs and PFCs, they could have significantly 

higher GWPs. Based on the ratios shown in Table 10 below, the average RE/MW ratios for the saturated 

fluorinated esters (fluorinated acetates and formates) are higher than the average RE/MW ratios for the 

saturated HFCs and PFCs, but are still within a factor of two. Similarly, the RE/MW ratio for vinyl 2,2,2-

 

8 Many estimates of GHGs’ radiative efficiencies are based on the assumption that the GHGs are well-mixed in the atmosphere. 

For GHGs with lifetimes of a few months or less, this assumption is not realistic and leads to overestimates of the radiative

efficiencies (and GWPs) of the GHGs. The GWPs and radiative efficiencies included in Hodnebrog et al. (2013) and AR5 reflect 

corrections to the radiative efficiencies of short-lived GHGs to mitigate this overestimate. 

9 This precise GWP was calculated using the atmospheric lifetime and the corrected radiative efficiency provided in the AR5.

10 Saturated fluorinated esters were included because radiative efficiency information was available for only one unsaturated 

fluorinated ester, vinyl 2,2,2-trifluoroacetate, and because their inherent radiative properties were expected to be similar to 

those of unsaturated fluorinated esters. Uncorrected radiative efficiencies were used in order to permit a comparison between 

the saturated and unsaturated compounds in the absence of atmospheric lifetime.
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 26

trifluoroacetate (unsaturated ester) is higher than the RE/MW ratios of the unsaturated HFCs and PFCs, 

but is still within a factor of two. Based on this analysis, it appears likely that the average GWPs for the 

unsaturated fluorinated esters are likely to be near 1, and that it is appropriate to assign these 

compounds a default GWP of 1. 

Table 10. Comparison of Radiative Efficiency to Molecular Weight Ratios of Saturated and 

Unsaturated HFCs and PFCs

Fluorinated GHG Group RE/MW Ratio

Saturated PFC 0.0014

Saturated HFC 0.0015

Unsaturated PFC 0.0015

Unsaturated HFC 0.0018

Fluorinated Acetates 0.0025

Formate 0.0025

Unsaturated Ester 0.0027

Therefore, the default GWP of 1 is expected to be accurate for the unsaturated halogenated esters 

whose atmospheric behavior has not yet been studied. ICF’s analysis suggests that this group be could 

added to the previously existing group of compounds assigned a GWP of 1.

e. Partially Segregated and Non-Segregated Saturated HFEs and HCFEs

3M suggested disaggregating “saturated HFEs and HCFEs” into ‘partially segregated’ and ‘nonsegregated’ HFEs and HCFEs to more accurately reflect the GWPs of this group. 3M noted that partially 

segregated HFEs display significantly shorter atmospheric lifetimes and lower GWPs than nonsegregated HFEs. ICF evaluated this suggestion by disaggregating saturated HFEs and HCFEs into two

groups using the following classifications:

 Partially segregated compounds contain a fully hydrogenated alkyl group on one side of the 

oxygen with no fluorine substitutes and a partially or fully fluorinated alkyl group on the other 

side.

 Non-segregated compounds contain fluorine substitutes on all alkyl groups, but are not 

necessarily fully fluorinated.

For example, HFE-449s1 (C4F9OC2H5) and HFE-569sf2 (C4F9OC2H5) are segregated HFEs with the ether 

oxygen separating a fully fluorinated and a fully hydrogenated alkyl group, while HFE-347pcf 

(CF2HCF2OCH2CF3) is a non-segregated HFE with oxygen separating two partially fluorinated alkyl groups 

(IPCC/TEAP, 2005). 

In its comments, 3M did not explain the mechanism through which the segregation of fluorine atoms in 

HFE molecules leads to shorter lifetimes. However, Owens (1999) notes that the “segregated structure 

maximizes the effect of the ether oxygen in reducing the atmospheric lifetimes.” Owens further notes 

that fluorine can decrease the activating effect of the ether and states, “although there can be a 

deactivating effect from fluorine atoms across the ether bond, it is much less pronounced than that 

produced by fluorine atoms on the same alkyl group. This segregated structure appears to buffer the 

hydrogen atoms from the very electronegative fluorine atoms taking full advantage of the activating 

effect of the ether oxygen.”
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 27

The histogram below shows the GWPs of the saturated HFEs and HCFEs sorted into partially segregated 

and non-segregated HFEs and HCFEs in order to evaluate whether this separation of saturated HFEs and 

HCFEs is an indicator of whether a compound is likely to have a low or high GWP, and whether this 

separation would therefore be a valuable distinction to make when establishing F-GHG groups. 

Figure 2. Histogram comparing GWPs of partially segregated and non-segregated saturated HFEs and 

HCFEs.

The table below shows the average GWPs, standard deviations, and proposed default GWPs of each 

sub-group based on ICF’s evaluation, as well as the same values for the aggregated group of saturated 

HFEs and HCFEs.

Table 11. Comparison of Average GWPs of Saturated HFE and HCFE Groups

Saturated HFE Group

Proposed 

GWP

(100-year)

Average 

GWP 

(100-year)

Standard 

Deviation

Average

Atmospheric 

Lifetime

Saturated HFEs and HCFEs 1,600a 1,536 2,536 10.0

Partially segregated saturated HFEs and HCFEs 200 204 227 1.8

Non-segregated saturated HFEs and HCFEs 2,400 2,436 2,967 15.5

aDefault proposed in Proposed Amendments to Subpart L based on previously calculated average GWP (see footnote “a” to 

Table 1).

As shown by Figure 2 and Table 11, the distinction between the partially segregated and non-segregated 

saturated HFEs and HCFEs captures pervasive (though not universal) differences in GWPs among the 

saturated HFEs and HCFEs. Most partially segregated HFEs and HCFEs have GWPs below 500, while most 

non-segregated HFEs and HCFEs have GWPs greater than 500. However, there are outliers in both 

groups. For example, the (lower-GWP) partially segregated HFE group with a default GWP of 200 would 

include HFE-143a (CH3OCF3), which has a lifetime of 4.3 years and GWP of 756. 

0

2

4

6

8

10

12

0 to 100 100 to 250 250 to 500 500 to 750 750 to

1,000

1,000 to

2,500

2,500 to

5,000

5,000 to

7,500

7,500 to

10,000

Over

10,000

Frequency

GWP Range

Partially Segregated Non-Segregated
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 28

Despite these known outliers, the two sub-groups of saturated HFEs and HCFEs are based on chemical 

structure, which could more accurately categorize the HFEs, and potentially assign the saturated HFEs

and HCFEs more representative GWPs. Therefore, these new groupings are likely to apply to HFEs and 

HCFEs whose atmospheric behavior has not yet been studied. 

Additional analysis of the GWPs of saturated HFEs and HCFEs, including an analysis of the relationship 

between these GWPs and the numbers of carbon-hydrogen (C-H) and carbon-fluorine (C-F) bonds in the 

molecule, can be found in “Revised Analysis of Atmospheric Lifetimes, Radiative Efficiencies, and Global 

Warming Potentials of Saturated Hydrofluoroethers by Number of Carbon-Hydrogen and CarbonFluorine Bonds.”

f. Fluorinated GHGs with One or More Carbon-iodine Bond

DuPont suggested forming an additional group for fluorinated compounds containing one or more 

carbon-iodine bonds, because any fluorinated compound with a carbon-iodine bond is expected to 

photodissociate readily, resulting in an atmospheric lifetime of a few hours and an approximate GWP of 

1. ICF found the following evidence to support this suggestion:

 A three-dimensional global chemistry-transport model (CTM) of the troposphere and 

stratosphere was used to evaluate the potential effects of CF3I, a very short-lived iodinated 

compound. The model indicated that this compound has a lifetime of 5.03 days and 1.13 days 

for emissions assumed to be evenly distributed over land surfaces at mid-latitudes and the 

tropics, respectively (Youn et al., 2010). Furthermore, according to IPCC AR4, CF3I has a direct 

100-year GWP of 0.4 and lifetime of 0.005 years. This direct GWP does not account for any 

stratospheric ozone depletion by CF3I, which is likely to be negligible and would be expected to 

decrease the GWP.

 A study on the reactions of fluorotelomer iodide (n-C4F9CH2CH2I) calculated that the 

atmospheric lifetime of this iodinated compound is determined by photolysis and is a few days

(Young et al., 2008). 

 Approximately ten fluorinated iodine compounds have been examined by scientists, and all have 

very short lifetimes (i.e. 5 days or less) because they photolyze rapidly resulting in GWP values 

less than 1 (Wuebbles, 2014). 

Based on the results of these studies and DuPont’s supporting information, any fluorinated compound 

with a carbon-iodine bond is expected to have a very short atmospheric lifetime and could therefore be 

assigned a GWP of 1. 

g. Formates

During this analysis, ICF noticed that the eight formates categorized as “other fluorinated compounds” 

have an average GWP of 350 and an average lifetime of 2.5 years. For example, according to IPCC AR5, 

trifluoromethyl formate has a 100-year GWP of 588 and a lifetime of 3.5 years while 2,2,2-trifluoroethyl 

formate has a 100-year GWP of 33 and a lifetime of 0.4 years. Removing these eight compounds from 

the list of “other fluorinated compounds” results in an average GWP for the “other fluorinated 

compounds” of 20 and an average lifetime of 0.3 years. To improve the accuracy and precision of the 

proposed GHG groups, one potential action is to remove formates from “other fluorinated compounds” 

and create a new “formates” group with a default GWP of 350. 11

 

11 Note: Dr. Weubbles did not provide feedback on this observation. 
Revised Analysis of Default GWPs for Fluorinated GHGs Reported Under the GHGRP 

Page 29

However, revising the GWP of “other fluorinated compounds” to 20 may not be appropriate as a new 

compound with an inherently higher GWP than 20 could be reported in the future and fall into this 

group. Therefore, it may be preferable to retain the more conservative GWP of 100 for “other 

fluorinated compounds” in the event a high-GWP compound is assigned to this group.