# MEMORANDUM To: Debbie Ottinger, EPA Cc: Don Wuebbles, University of Illinois From: Mollie Averyt, Rebecca Ferenchiak, Deborah Harris, and Mark Flugge , ICF Date: November 1 5 , 2013 Re: Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP (EPA Contract Number EP - BPA - 12 - H - 0022 , EP - B13H - 00006/ Task Order 007 : Support for Implementing and Refining Mandatory GHG Reporting Requirements for Various Emitters of Fluorinated GHGs , Task 3 : Support for Evaluation of GWPs ) 

## Introduction T his memorandum presents a summary of an ICF analysis to develop default Global Warming Potentials (GWPs) for fluorinated compounds without documented GWPs . Through the Greenhouse Gas Reporting Program (GHGRP) , EPA receives reports of emissions of several compounds that do not have GWPs listed on Table A - 1, the GHGRP’s compendium of GWPs. D efault GWPs would ensure that the atmospheric impacts of these and other target compounds are appropriately reflected in facilities’ calculations and reports under the GHGRP . This analysis develops d efault GWPs for different model groups of compound s . These defaults could be assigned to target compounds based on which model group of compounds the target compounds align with . The purpose of the analysis is to: 1. C onsider which sets of compound s should be used as the basis for default GWP s for the different groups of fluorinated GHGs whose GWPs do not appear on Table A - 1 , 2. Calculate the a verage and t he average plus one 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:

 Analysis Method  Results of the Analysis  Comparison between Defaults and GWPs Estimated by 3M for Several F - GHGs  Evaluation of Analysis Method by Dr. Wuebbles and Recommendations  Appendix A: F - GHGs by Model Group Please contact Mark Flugge at (202) 862 - 1231 ( Mark.Flugge@icfi.com ) with any questions or comments.

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 2 of 25 

## Analysis **Method** In establishing the default GWPs for the compound groups , EPA’s 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 applied the following criteria to assess potential compound groups : (1) c ollectively , the compound groups should span the full range of atmospheric behavior (atmospheric lifetimes and GWPs) observed among fluorinated GHGs , (2) w ithin each compound group , the compounds should be chemically similar and exhibit similar atmospheric behavior , and (3) compound s who se 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 are included in the calculation when the possibility exists that such outl iers may also occur among the fluorinated GHGs whose GWPs are being modeled. 1 

### In order to establish different compound groups and evaluate potential defaul t GWP ( s ) for each group, ICF reviewed the chemical structure , GWPs, and atmospheric lifetimes of the fluorinated GHGs with peer - reviewed GWP s. The F - GHGs with peer - reviewed GWP s include the compounds on Table A - 1 as well as those found in the article, “Global Warming Potentials and Radiative Efficiencies of Halocarbons and Related Compounds: A Comprehensive Review,” 2 

### (hereinafter referred to as the “Comprehensive Review”). As indicated by its name, the Comprehensive Review consolidates and updates the GWPs found in the peer - reviewed literature for numerous halogenated compounds . Ninety - six F - GHGs from the Comprehensive Review 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 GWP s from Table A - 1 as they were proposed to be updated in the “2013 Revisions to the Greenhouse Gas Reporting Rule and Proposed Confidentiality Determinations for New or Substantially Revised Data Elements” (78 FR 19802 ; April 2, 2013). For compound s that are included only in the Comprehensive Review, ICF used the GWP from the Comprehensive Review in the analysis, with the following exceptions. Several compounds within the Comprehensive Review were listed with a GWP of “ 0,” “<1,” or “<2.” 3 

### 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 Comprehensiv e Review. These compound s were grouped into four main model groups: (1) fully fluorinated fluorocarbons ( including fully fluorinated straight chain and cyclic alkanes, fully fluorinated ethers, perfluoropolyethers , and SF 5 

### CF 3 ) 

### as well as NF 3 

### and SF 6 

### ; ( 2 ) saturated HFCs and saturated HFEs and HCFEs ; ( 3 ) unsaturated PFCs, unsaturated HFCs and HCFCs , unsaturated HFEs, and fluorinated ketones ; and ( 4 ) other fluorinated GHGs . Within these four main model groups, there are also a few chlorine containing compound s that are not regulated as ozone - depleting substances under 40 CFR Part 82, and are therefore included in the definition of “fluorinated GHG.” These compounds have been grouped with chemically similar compounds that do not contain chlorine. The four model groups were also further evaluated with and without chemical and numerical outliers and by atmospheric lifetime (e.g., lifetimes greater than or less than 20 years for saturated HFCs and

1 For the purposes of this analysis, a compound is identified as a numerical outlier if the value of the compound’s GWP is greater than the default GWP plus two standard deviations for the compound’s model group. 2 Hodnebrog, Ø., M. Etminan, J. S. Fuglestve dt, G. Marston, G. Myhre, C. J. Nielsen, K. P. Shine, and T. J. Wallington, “Global Warming Potentials and Radiative Efficiencies of Halocarbons and Related Compounds: A Comprehensive Review,” Reviews of Geophysics , Accepted manuscript online: 24 APR 2013. 3 These compounds are identified in Appendix A.

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 3 of 25 saturated HFEs ), resulting in 20 different average subgroup GWPs . 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 . 4 

## Results of the **Analysis** The average GWP, rounded average GWP, standard deviation , and average GWP plus one standard deviation for each of the 20 model groups are presented in Table 1. The complete list of compounds within each model group can be found in Appendix A. Table 1 : Model Group GWPs Model Group Average GWP Rounded Average

GWP Standard Deviation (St. Dev.) Average GWP + 1 St . Dev . 1 Fully Fluorinated GHGs excluding F - GHGs not containing Carbon 9,857 10,0 00 3,450 13,306 1+1a Fully Fluorinated GHGs including F - GHGs not containing Carbon 11,050 11,000 4,769 15,819 1 − o Fully Fluorinated GHGs excluding F - GHGs not containing Carbon and Outliers 8,678 9,000 1,608 10,285 2 Saturated HFCs, HFEs, and HCFEs 1,747 1,700 2,807 4,554 2a Saturated HFCs 2,187 2,200 3,346 5,534 2a − o Saturated HFCs excluding Outliers 1,344 1,300 1,409 2,753

2b Saturated HFEs and HCFEs 1,559 1,600 2,551 4,110 2b − o Saturated HFEs and HCFEs excluding Outliers 1,235 1,200 1,727 2,962 2c Saturated HFCs with lifetime >20 years 5,678 5,700 4,373 10,051 2d Saturated HFCs with lifetime <20 years 636 640 557 1,193

4 The number of significant figures to which the average GWPs were rounded depended on the relative and absolute errors associated with that number of significant figures. In general, GWPs were rounded to t wo significant figures when the average GWP was greater than 100, reflecting uncertainties in the average of a few percent. One exception was the rounded average GWP for Fully Fluorinated GHGs excluding F - GHGs not containing Carbon (Group 1), which was ro unded to one significant figure (10,000) rather than two (9,900) because the uncertainty associated with the second figure (i.e., ±100) is only about one percent of the average GWP for the group. Rounding the Group 1 average to the nearest 100 (9,900) wou ld understate the uncertainty associated with the default and result in a less robust default that would be more sensitive to small changes in the set of GWPs used to calculate the default. The average GWP for Group 1 - o was also rounded to one significant figure for the same reasons. GWPs of less than one were rounded to one decimal place because, for the affected gases, the absolute error in CO 2 e emissions that is associated with this rounding is expected to be small.

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 4 of 25 Model Group Average GWP Rounded Average

GWP Standard Deviation (St. Dev.) Average GWP + 1 St . Dev . 2e Saturated HFEs and HCFEs with lifetime >20 years 6 , 217 6,200 3,259 9,476 2f Saturated HFEs and HCFEs with lifetime <20 years 646 650 840 1,485 2g Saturated HFCs, HFEs, and HCFEs with lifetime >20 years 5,977 6,000 3,685 9,662 2h Saturated HFCs, HFEs, and HCFEs with lifetime <20 years 643 640 774 1,418 3 Unsaturated PFCs, HFCs, and HFEs and Fluorinated Ketones 0.42 0.4 0.62 1 .04 3a Unsaturated PFCs 0.66 0.7 0.96 1.62 3b Unsaturated HFCs and HCFCs 0.38 0.4 0.50 0.88 3c Unsaturated HFEs 0.11 0.1 - 0.11 3d Fluorinated Ketones 0.11 0 .1 - 0.11 4 Other Fluorinated GHGs 103 100 183 285 The rounded average model group GWPs range between 0.1 and 11, 0 0 0 . The exclusion of the two fully fluorinated GHGs that do not contain carbon (i.e., SF 6 

### and NF 3 

### ) in Model Group 1 decreases the average model group GWP by about 1, 2 00 compared to Model Group 1+1a . The average GWPs for the saturated HFCs and HFEs with lifetimes greater than 20 years are more than nine times larger than average GWPs for the saturated HFCs and HFEs with lifetimes less than 20 years. The average GWP for the unsaturated HFEs and fluorinated ketones (Model Groups 3c and 3d, respectively) within Model Group 3 have the smallest average model group GWP compared to the other 18 average model group GWPs. Figure s 1 through 8 show the GWPs of all the compound s within the four model groups . In each figure, the compounds are sorted first by subgroup (i.e., structural similarities) and then further by atmospheric lifetime and with or without chemical or numerical outliers, as applicable. The GWPs that are patterned represent numerical outliers within the model groups (i.e., the proposed GWP for the F GHG is greater than the default GWP plus two standard deviations for the compound’s model group) . For very long - lived gases , relatively high 100 - year GWPs are generally a consequence of the compound’s radiative eff iciency (or more precisely, the ratio between the compound’s radiative efficiency and its molecular weight). This in turn is influenced by the compound’s inclusion of bonds other than C - F bonds (e.g., S - F or N - F bonds in SF 6 

### , SF 5 

### CF 3 

### , and NF 3 

### ) or by a cycli c structure (as for c C 3 

### F 6 

### ). SF 6 

### and NF 3 

### (Model Group 1a) are considered chemical outliers because the definition of “fluorinated GHG” does not include compounds whose radiatively important bonds consist exclusively of S - F or N - F bonds. However, SF 5 

### CF 3 

### is included in Model Group 1 because the definition of “fluorinated GHG” does include fluorocarbons, which may include S - F and N - F bonds in addition to C - F bonds. Cyclic fluorinated GHGs are also included in Model Group 1 for the same reason. Within the

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 5 of 25 other compound groups, relatively high - GWP compounds are those that are relatively long - lived, such as HFC - 23 among the saturated HFCs and HFE - 125 and HFE - 134 among the saturated HFEs, while relatively low - GWP compounds are those that are short - lived, such as HFC - 152a among the saturated HFCs. The horizontal lines across the figure s represent the suggested (i.e., rounded) model sub group default GWPs. The suggested GWP for M odel G roup 1+1a , is greater than the GWPs of all but five of the compounds within the model group (i.e., C 2 

### F 6 

### , NF 3 

### , perfluorocyclobutane, SF 5 

### CF 3 

### , and SF 6 

### ) . Two of those f ive compounds (i.e., NF 3 

### and SF 6 

### ) are considered to be chemical outliers , because they do not include the C - F bonds that are the primary source of radiative forcing i n the target compounds . 5 

### The suggested model group GWP for Model Group 1+1a , therefore , is the most inclusive of GWPs within the model groups , but is not necessarily representative of the target compounds . The suggested subgroup GWP for Model Group 2 g (Saturate d HFCs, HFEs, and HCFEs with lifetime >20 years) is higher than the GWPs of the majority of compounds within Model Group 2, as saturated compounds with longer lifetimes tend to have higher GWPs. Figure 1: Fully Fluorinated GHGs (Model Group 1+1a, including 1 and 1 − o) and Average GWPs

Note: Patterned compounds indicate identified numerical outliers . Compounds 16 (SF 6 ) and 17 (NF 3 ) are also chemical outliers.

5 The target compounds consist of “fluorinated GHGs” as defined in part 98. Other than NF 3 and SF 6 , all “ fluorinated GHGs ” are fluorocarbons , including both carbon and fluorine. Some may also contain other elements . 0 5000 10000 15000 20000 25000

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17GWP

Model Group 1+1a GWPs 1 Avg: Fully Fluorinated GHGs excluding F-GHGs not containing Carbon 1+1a Avg: Fully Fluorinated GHGs including F-GHGs not containing Carbon 1-o Avg: Fully Fluorinated GHGs excluding F-GHGs not containing Carbon and Outliers

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 6 of 25 Figure 2 : Saturated HFCs, HFEs, and HCFEs (Model Group 2, including 2g and 2h ) and Average GWPs

Note: Compounds 1 – 18 are Model Group 2 g ; Compounds 19 – 8 7 are Mode l Group 2h. 

### Figure 3 : Saturated HFCs ( Model Group 2a , including 2a - o, 2c, and 2d) and Average GWPs

Note: Patterned compounds indicate identified numerical outliers ; Compounds 1 – 20 are Model Group 2d; Compounds 21 – 26 are Model Group 2c. 0 5000 10000 15000 20000

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85GWP

Model Group 2 GWPs 2 Avg: Saturated HFCs, HFEs, and HCFEs 2g Avg: Saturated HFCs, HFEs, and HCFEs with lifetime > 20 years 2h: Avg Saturated HFCs, HFEs, and HCFEs with lifetime < 20 years

0 2000 4000 6000 8000 10000 12000 14000 16000

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26GWP

Model Group 2a GWPs 2a Avg: Saturated HFCs 2c Avg: Saturated HFCs with lifetime > 20 years 2d Avg: Saturated HFCs with lifetime < 20 years 2a-o Avg: Saturated HFCs excluding Outliers

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 7 of 25 Figure 4 : Saturated HFCs with Lifetimes >20 years (Model Group 2c) and Average GWPs

Figure 5 : Saturated HFCs with Lifetime < 20 years (Model Group 2d) and Average GWPs 0 2000 4000 6000 8000 10000 12000 14000 16000

1 2 3 4 5 6 7 8GWP

Model Grooup 2c 2c Avg: Saturated HFCs with lifetime > 20 years

0 200 400 600 800 1000 1200 1400 1600 1800

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18GWP

Model Group 2d 2d Avg: Saturated HFCs with lifetime < 20 years

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 8 of 25 Figure 6 : Saturated HFEs and HCFEs (Model Group 2b, including 2b − o, 2e, and 2f) and Average GWPs

Note: Patterned compounds indicate identified numerical outliers ; Compounds 1 – 51 are Model Group 2f; Compounds 52 – 61 are Model Group 2e .



### Figure 7 : Unsaturated PFCs, HFCs, and HFEs and Fluorinated Ketones (Model Group 3 , including 3a, 3b, 3c, and 3d ) and Average GWPs

Note: Compounds 1 – 6 are Model Group 3a; Compounds 7 – 21 are Model Group 3b; Compounds 22 – 23 are Model Group 3c; Compound 23 is Model Group 3d. 0 2000 4000 6000 8000 10000 12000 14000 16000

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61GWP

Model Group 2b GWPs 2b Avg: Saturated HFEs and HCFEs 2b-o Avg: Saturated HFEs and HCFEs excluding Outliers 2e Avg: Saturated HFEs and HCFEs with lifetime > 20 years 2f: Avg Saturated HFEs and HCFEs with lifetime < 20 years

0.00 0.50 1.00 1.50 2.00

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23GWP

Model Group 3 GWPs 3 Avg: Unsaturated PFCs, HFCs, and HFEs and Fluorinated Ketones 3a Avg: Unsaturated PFCs 3b Avg: Unsaturated HFCs and HCFCs 3c Avg: Unsaturated HFEs 3d Avg: Fluorinated Ketones

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 9 of 25 Figure 8 : Other Fluorinated GHGs ( Model Group 4 ) and Average GWPs

Figure 9 is a semi log graph that illustrates the number of chemicals in each chemical group whose GWPs fall with in different orders of magnitude. The left - most column represents the number of compound with GWPs betw een 0.001 and 0.01; the second bar represents compounds with GWPs between 0.01 and 0.1 ; etc. T he majority of the saturated HFCs and HFEs and HCFES with lifetimes greater than 20 years (Model Groups 2c and 2e ) have GWPs between 1,000 and 10,000 and the majority of the saturated HFCs and HFEs and HCFEs with lifetimes less than 20 years (Model Group s 2d and 2f ) have GWPs between 100 and 1,000. The majority of the unsaturated PFCs, HFCs, HFEs, and fluorinated ketones (Model Groups 3a, 3b, 3c, and 3d, respec tively) have GWPs less than 10, and most of the other fluorinated GHGs (Model Group 4) have GWPs less than 100. 0 100 200 300 400 500 600 700

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31GWP

Model Group 4 GWPs 4 Avg: Other Fluorinated GHGs

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 10 of 25 Figure 9 : Histogram of Model Compound GWPs

Note: Compounds that are included in more than one Model Group were only counted once. For example, Model Group 2 (Saturated HFCs, HFEs, and HCFEs) is not explicitly shown in Figure 9 , but contains all chemicals in Model Groups 2c, 2d, 2e, 2f, 2g, and 2h . 

## Comparison **between Defaults and GWPs Estimated by**  **3M f**  **or Several F**  **- GHGs**  ICF tested t he accuracy of default GWPs based on chemical groups by comparing the default GWPs to the GWPs of F - GHGs with documented GWPs provided by 3M. The first six compounds provided by 3M are full y fluorinated GHGs and would be assigned to Group 1: Fully Fluorinated GHGs exclud ing F GHGs not containing Carbon . The compounds within the 3M group have an average GWP of 9,452. This average GWP is similar to the suggested default GWP for Group 1, which is equal to 10,000 . The remaining two compounds provided by 3M, HFE - 7300 and HFE - 7 500, have an average GWP of 205 . Both HFE - 7300 and HFE - 7500 have atmospheric lifetimes of 3.8 and 2.2 years, respectively, and c ould be assigned to Group 2f: Saturated HFEs and HCFEs with lifetime <20 years, which has a suggested default GWP of 650 . The co mpounds could also be assigned to Group 2b, saturated HFEs and HCFEs of all lifetimes, which has a suggested default GWP of 1, 600 . The larger difference between the estimated GWPs and the default GWP for Group 2b is not surprising; a s shown in Table 1, the variability (standard deviation) of the GWPs in Group 2b is considerably larger than that of the GWPs in Group 2f. 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 1: Fully Fluorinated GHGs and SF5CF3 1a: Fully Fluorinated GHGs without Carbon 2c: Saturated HFCs with lifetime > 20 years 2d: Saturated HFCs with lifetime < 20 years 2e: Saturated HFEs and HCFEs with lifetime > 20 years 2f: Saturated HFEs and HCFEs with lifetime < 20 years 3a: Unsaturated PFCs 3b: Unsaturated HFCs 3c: Unsaturated HFEs 3d: Fluorinated Ketones 4: Other Fluorinated GHGs

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 11 of 25 Table 2: 3M Company Fluorinated GHGs GWPs and Default GWP Comparison Chemical Designation or Common Name Chemical Formula 3M Su bmitted GWP Default GWP Perfluorotripropyl amine (PTPA) C 9 

### F 21 

### N 8,690 10,000 Perfluorotributyl amine (PTBA) C 12 

### F 27 

### N 9,020 10,000 Perfluorotriamyl amine (PTAA) C 15 

### F 33 

### N 8,900 10,000 Perfluoromethyl morpholine (PMM) C 5 

### F 11 

### NO 9,500 10,000 Perfluoroisopropyl morpholine (PIPM) C 7 

### F 15 

### NO 11,000 10,000 2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9 - hexadecafluorooxonane C 8 

### F 16 

### O 9,600 10,000 1,1,1,2,2,3,4,5,5,5 - decafluoro - 3 - methoxy - 4 - trifluoromethyl - pentane ( HFE - 7300) 310 650 3 - ethoxy - 1,1,1,2,3,4,4,5,5,6,6,6 - dodecafluoro - 2 - trifluoromethyl - hexane (HFE - 7500) 100 650 

## 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 associa ted 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 based on the available information and time constraints. Dr. Wuebbles recommends 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 should all have short lifetimes) as a potential model group. Given this suggestion, Model Group 3 contains separate sub - groups for unsaturated PFCs, HFCs and HCFCs, and HFEs. ICF arranged and attended a conference call with EPA and Dr. Don Wuebbles on May 9, 2013 to discuss the results of the default GWP analysis, and to determine the most appropriate default GWP to assign to the target compounds. During confe rence call Dr. Wuebbles communicated that a less than one - year and greater than one - year threshold is perhaps more suitable compared to a 20 - year threshold when differentiating between compounds within a particular model group — i.e., compounds with a lifeti me greater than one year should be considered long lived regardless of their corresponding GWP. This was accomplished by creating and evaluating a model group that exclusively consists of short - lived compounds (i.e., Model Group 3, which contains unsaturat ed PFCs, HFCs and HCFCs, and HFEs). In addition, saturated HFCs, HFEs, and HCFEs (Model Group 2) continue to be evaluated on a less than or greater than 20 year lifetime basis. Dr. Wuebbles also noted that the IPPC process for developing Assessment Reports (e.g., the Fourth Assessment Report or AR4) is not designed to be the sole arbiter of “ official ” GWP values, and other

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 12 of 25 sources of published (i.e., peer - reviewed) literature (e.g., WMO, 2010) should be considered when establishing default GWP estimates. 6 

### I n addition, as a result of this discussion, numerical o utliers 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 . That said, the results of excl uding outliers for selected model groups are illustrated in the Results of the Analysis section above.

6 Note, however, that EPA is not aware of any peer - reviewed GWPs other tha n those included in the Comprehensive Review.

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 13 of 25 

## Appendix A: **F -**  **GHGs by Model Group** Model Group Common or Trade Name Chemical Designation CAS No. Chemical Formula GWP GWP Source # 1 Fully Fluorinated GHGs PFPMIE (HT - 70) perfluoropolymethylisopropyl ether 69991 - 67 - 9 CF 3 OCF(CF 3 )CF 2 OCF 2 OCF 3 10 , 300 AR4/Table A

- 1 1 Fully Fluorinated GHGs PFC – 14 Perfluoromethane 75 – 73 – 0 CF 4 7 , 390 ^ AR4/Table A

- 1 1 Fully Fluorinated GHGs PFC – 9 – 1 – 18 Perfluorodecalin 306 – 94 – 5 C 10 F 18 7 , 500 AR4/Table A

- 1 1 Fully Fluorinated GHGs PFC – 218 Perfluoropropane 76 – 19 – 7 C 3 F 8 8 , 830 ^ AR4/Table A

- 1 1 Fully Fluorinated GHGs PFC – 3 – 1 – 10 Perfluorobutane 355 – 25 – 9 C 4 F 10 8 , 860 ^ AR4/Table A

- 1 1 Fully Fluorinated GHGs PFC – 4 – 1 – 12 Perfluoropentane 678 – 26 – 2 C 5 F 12 9 , 160 ^ AR4/Table A

- 1 1 Fully Fluorinated GHGs PFC – 5 – 1 – 14 (FC - 72) Tetradecafluorohexane 355 – 42 – 0 C 6 F 14 9 , 300 ^ AR4/Table A

- 1 1 Fully Fluorinated GHGs PFC - 6 - 1 - 12 Hexadecafluoroheptane 335 - 57 - 9 C 7 F 16 , CF 3 (CF 2 ) 5 CF 3 7 , 820 CR 1 Fully Fluorinated GHGs PFC - 7 - 1 - 18 Octadecafluorooctane 307 - 34 - 6 C 8 F 18 , CF 3 (CF 2 ) 6 CF 3 7 , 620 CR 1 Fully Fluorinated GHGs PFC - 318 Perfluorocyclobutane 115 – 25 – 3 c - C 4 F 8 10 , 300 ^ AR4/Table A

- 1 1 Fully Fluorinated GHGs PFC – 116 Perfluoroethane 76 – 16 – 4 C 2 F 6 12 , 200 ^ AR4/Table A

- 1 1 Fully Fluorinated GHGs Perfluorocyclopropane 931 – 91 – 9 c - C 3 F 6 17 , 340 AR4/Table A

- 1 1 Fully Fluorinated GHGs Perfluorodecalin (cis) 60433 - 11 - 6 cis - C 10 F 18 7 , 240 CR 1 Fully Fluorinated GHGs Perfluorodecalin (trans) 60433 - 12 - 7 trans - C 10 F 18 6 , 290 CR 1 Fully Fluorinated GHGs Trifluoromethyl sulphur pentafluoride 373 – 80 – 8 SF 5 CF 3 17 , 700 AR4/Table A

- 1 1a Fully Fluorinated SF6 Sulfur hexafluoride 2551 – 62 – 4 SF 6 22 , 800 ^ AR4/Table A

- 1

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 14 of 25 Model Group Common or Trade Name Chemical Designation CAS No. Chemical Formula GWP GWP Source # GHGs - No Carbon 1a Fully Flu orinated GHGs - N o Carbon NF3 Nitrogen trifluoride 7783 – 54 – 2 NF 3 17 , 200 AR4/Table A

- 1 2d Saturated HFCs with lifetime < 20 years HFC – 161 353 – 36 – 6 CH 3 CH 2 F 12 AR4/Table A

- 1 2d Saturated HFCs with lifetime < 20 years HFC – 152 624 – 72 – 6 CH 2 FCH 2 F 53 AR4/Table A

- 1 2d Saturated HFCs with lifetime < 20 years HFC - 263fb 1,1,1 - Trifluoropropane 421 - 07 - 8 CH 3 CH 2 CF 3 76 CR 2d Saturated HFCs with lifetime < 20 years HFC – 152a 75 – 37 – 6 CH 3 CHF 2 124 ^ AR4/Table A

- 1 2d Saturated HFCs with lifetime < 20 years HFC – 41 593 – 53 – 3 CH 3 F 92 ^ AR4/Table A

- 1 2d Saturated HFCs with lifetime < 20 years HFC - 272ca 2,2 - Difluoropropane 420 - 45 - 1 CH 3 CF 2 CH 3 144 CR 2d Saturated HFCs with lifetime < 20 years HFC - 245eb 1,1,1,2,3 - Pentafluoropropane 431 - 31 - 2 CH 2 FCHFCF 3 290 CR 2d Saturated HFCs with lifetime < 20 years HFC - 245ea 1,1,2,3,3 - Pentafluoropropane 24270 - 66 - 4 CHF 2 CHFCHF 2 235 CR 2d Saturated HFCs with lifetime < 20 years HFC – 143 430 – 66 – 0 C 2 H 3 F 3 353 ^ AR4/Table A

- 1 2d Saturated HFCs with lifetime < 20 years HFC – 32 75 – 10 – 5 CH 2 F 2 675 ^ AR4/Table A

- 1 2d Saturated HFCs HFC – 245ca 679 – 86 – 7 C 3 H 3 F 5 693 ^ AR4/Table A

- 1

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 15 of 25 Model Group Common or Trade Name Chemical Designation CAS No. Chemical Formula GWP GWP Source # with lifetime < 20 years 2d Saturated HFCs with lifetime < 20 years HFC – 245fa 460 – 73 – 1 CHF 2 CH 2 CF 3 1,030 AR4/Table A

- 1 2d Saturated HFCs with lifetime < 20 years HFC – 365mfc 406 – 58 – 6 CH 3 CF 2 CH 2 CF 3 794 AR4/Table A

- 1 2d Saturated HFCs with lifetime < 20 years HFC – 134 359 – 35 – 3 CHF 2 CHF 2 1,100 ^ AR4/Table A

- 1 2d Saturated HFCs with lifetime < 20 years HFC – 236ea 431 – 63 – 0 CHF 2 CHFCF 3 1,370 AR4/Table A

- 1 2d Saturated HFCs with lifetime < 20 years HFC – 236cb 677 – 56 – 5 CH 2 FCF 2 CF 3 1,340 AR4/Table A

- 1 2d Saturated HFCs with lifetime < 20 years HFC – 134a 811 – 97 – 2 CH 2 FCF 3 1,430 ^ AR4/Table A

- 1 2d Saturated HFCs with lifetime < 20 years HFC – 43 – 10mee 138495 – 42 – 8 CF 3 CFHCFHCF 2 CF 3 1,640 ^ AR4/Table A

- 1 2c Saturated HFCs with lifetime > 20 years HFC - 227ca 1,1,1,2,2,3,3 - Heptafluoropropane 2252 - 84 - 8 CF 3 CF 2 CHF 2 2 , 640 CR 2c Saturated HFCs with lifetime > 20 years HFC - 329p 1,1,1,2,2,3,3,4,4 - Nonafluorobutane 375 - 17 - 7 CHF 2 CF 2 CF 2 CF 3 2 , 360 CR 2c Saturated HFCs with lifetime > 20 years HFC – 125 354 – 33 – 6 CHF 2 CF 3 3,500 ^ AR4/Table A

- 1 2c Saturated HFCs with lifetime > 20 HFC – 227ea 431 – 89 – 0 C 3 HF 7 3,220 ^ AR4/Table A

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### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 16 of 25 Model Group Common or Trade Name Chemical Designation CAS No. Chemical Formula GWP GWP Source # years 2c Saturated HFCs with lifetime > 20 years HFC - 245cb 1,1,1,2,2 - Pentafluoropropane 1814 - 88 - 6 CF 3 CF 2 CH 3 4 , 620 CR 2c Saturated HFCs with lifetime > 20 years HFC – 143a 420 – 46 – 2 C 2 H 3 F 3 4,470 ^ AR4/Table A

- 1 2c Saturated HFCs with lifetime > 20 years HFC – 236fa 690 – 39 – 1 C 3 H 2 F 6 9,810 ^ AR4/Table A

- 1 2c Saturated HFCs with lifetime > 20 years HFC – 23 75 – 46 – 7 CHF 3 14,800 ^ AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years HFE – 263fb2 1,1,1 - Trifluoro - 2 - methoxyethane 460 - 43 - 5 CF 3 CH 2 OCH 3 11 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years HFE – 356mmz1 1,1,1,3,3,3 - Hexafluoro - 2 - methoxypropane 13171 - 18 - 1 C 4 H 4 F 6 O 27 Table A - 1 2f Saturated HFEs with lifetime < 20 years HFE – 365mcf3 1,1,1,2,2 - Pentafluoro - 3 - methoxypropane 378 - 16 - 5 CF 3 CF 2 CH 2 OCH 3 11 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years HFE – 356pcc3 1,1,2,2,3,3 - Hexafluoro - 1 - methoxypropane 160620 - 20 - 2 CH 3 OCF 2 CF 2 CHF 2 110 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years R - E - 143a; HFE 263m1 1,1,2,2 - Tetrafluoro - 1 - (trifluoromethoxy)ethane 690 - 22 - 2 CF 3 OCH 2 CH 3 29 CR 2f Saturated HFEs with lifetime < 20 years HFE - 365mcf2 1 - Ethoxy - 1,1,2,2,2 - pentafluoroethane 22052 - 81 - 9 CF 3 CF 2 OCH 2 CH 3 58 CR 2f Saturated HFEs with lifetime < 20 years HFE - 569sf2, (HFE 7200) Isomer blend 1 - Ethoxy - 1,1,2,2,3,3,4,4,4 - nonafluorobutane 163702 - 05 - 4 C 4 F 9 OC 2 H 5 59 AR4/Table A

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### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 17 of 25 Model Group Common or Trade Name Chemical Designation CAS No. Chemical Formula GWP GWP Source # 2f Saturated HFEs with lifetime < 20 years HFE – 356mec3 1,1,1,2,3,3 - Hexafluoro - 3 - methoxypropane 382 - 34 - 3 CH 3 OCF 2 CHFCF 3 101 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years HFE – 356pcf2 1 - (2,2 - Difluoroethoxy) - 1,1,2,2 - tetrafluoroethane 50807 - 77 - 7 CHF 2 CH 2 OCF 2 CHF 2 265 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years HG' - 01 1,1,2,2 - Tetrafluoro - 1,2 - dimethoxyethane 73287 - 23 - 7 CH 3 OCF 2 CF 2 OCH 3 222 CR 2f Saturated HFEs with lifetime < 20 years HG' - 02 1,1,2,2 - Tetrafluoro - 1 - methoxy - 2 - (1,1,2,2 - tetrafluoro - 2 - methoxyethoxy)ethane 485399 - 46 - 0 CH 3 O(CF 2 CF 2 O) 2 CH 3 236 CR 2f Saturated HFEs with lifetime < 20 years HG' - 03 3,3,4,4,6,6,7,7,9,9,10,10 - Dodecafluoro - 2,5,8,11 - tetraoxadodecane 485399 - 48 - 2 CH 3 O(CF 2 CF 2 O) 3 CH 3 221 CR 2f Saturated HFEs with lifetime < 20 years HFE – 245fa1 1,1 - Difluoro - 2 - (trifluoromethoxy)ethane 84011 - 15 - 4 CHF 2 CH 2 OCF 3 286 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years Sevoflurane (HFE 347mmz1) 2 - (Difluoromethoxy) - 1,1,1,3,3,3 - hexafluoropropane 28523 - 86 - 6 (CF 3 ) 2 CHOCHF 2 216 CR 2f Saturated HFEs with lifetime < 20 years HFE – 245cb2 1,1,1,2,2 - Pentafluoro - 2 - methoxy - ethane 22410 - 44 - 2 CF 3 CF 2 OCH 3 708 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years HFE – 254cb1 1,1,2,2 - Tetrafluoro - 1 - methoxyethane 425 - 88 - 7 CH 3 OCF 2 CHF 2 359 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years Isoflurane (HCFE – 235da2) (2 - chloro - 2 - (difluoromethoxy) - 1,1,1 - trifluoro - ethane) 26675 - 46 - 7 C 3 H 2 ClF 5 O 350 + AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years HFE – 338mcf2 1,1,1,2,2 - Pentafluoro - 2 - (2,2,2 - trifluoroethoxy)ethane 156053 - 88 - 2 CF 3 CH 2 OCF 2 CF 3 552 AR4/Table A

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### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 18 of 25 Model Group Common or Trade Name Chemical Designation CAS No. Chemical Formula GWP GWP Source # 2f Saturated HFEs with lifetime < 20 years HFE – 347mcf2 1 - (2,2 - Difluoroethoxy) - 1,1,2,2,2 - pentafluoroethan 171182 - 95 - 9 CHF 2 CH 2 OCF 2 CF 3 374 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years HFE – 356pcf3 35042 – 99 – 0 CHF 2 OCH 2 CF 2 CHF 2 502 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years HFE – 236fa 20193 – 67 – 3 CF 3 CH 2 OCF 3 487 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years HFE – 347mmy1 22052 – 84 – 2 CH 3 OCF(CF 3 ) 2 343 Table A - 1 2f Saturated HFEs with lifetime < 20 years HFE - 449sl, (HFE 7100) Isomer blend 163702 – 07 – 6 C 4 F 9 OCH 3 297 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years HFE - 356mff2 BIS(2,2,2 - TRIFLUOROETHYL) ETHER 333 - 36 - 8 CF 3 CH 2 OCH 2 CF 3 17 CR 2f Saturated HFEs with lifetime < 20 years HFE – 143a 421 – 14 – 7 CH 3 OCF 3 756 AR4/Table A - 1 2f Saturated HFEs with lifetime < 20 years HFE – 245fa2 2 - (Difluoromethoxy) - 1,1,1 - trifluoroethane 1885 - 48 - 9 CHF 2 OCH 2 CF 3 659 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years HFE – 374pc2 512 – 51 – 6 CH 3 CH 2 OCF 2 CHF 2 557 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years HFE – 347mcc3 375 - 03 - 1 CH 3 OCF 2 CF 2 CF 3 575 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years Desflurane (HFE – 236ea2) 2 - (Difluoromethoxy) - 1,1,1,2 - tetrafluoroethane 57041 - 67 - 5 CHF 2 OCHFCF 3 989 AR4/Table A

- 1 2f Saturated HFEs HFE – 338pcc13 (HG – 188690 – 78 – 0 CHF 2 OCF 2 CF 2 OCHF 2 1 , 500 AR4/Table A

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### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 19 of 25 Model Group Common or Trade Name Chemical Designation CAS No. Chemical Formula GWP GWP Source # with lifetime < 20 years 01) 2f Saturated HFEs with lifetime < 20 years HFE – 43 – 10pccc (H – Galden 1040x) E1730133 CHF 2 OCF 2 OC 2 F 4 OCHF 2 1 , 870 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years HFE – 329mcc2 1,1,1,2,2 - Pentafluoro - 2 - (1,1,2,2 - tetrafluoroethoxy)ethane 134769 - 21 - 4 CHF 2 CF 2 OCF 2 CF 3 919 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years HFE – 347pcf2 1,1,2,2 - Tetrafluoro - 1 - (2,2,2 - trifluoroethoxy)ethane 406 - 78 - 0 CHF 2 CF 2 OCH 2 CF 3 580 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years HFE – 227ea 2356 – 62 – 9 CF 3 CHFOCF 3 1 , 540 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years HFE – 236ca12 (HG – 10) Bis(difluoromethoxy)difluoro methane 78522 - 47 - 1 CHF 2 OCF 2 OCHF 2 2 , 800 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years 1,1,2,2 - Tetrafluoro - 3 - methoxy - propane; Methyl 2,2,3,3 - tetrafluoropropyl ether 60598 - 17 - 6 CHF 2 CF 2 CH 2 OCH 3 0.49 * CR

2f Saturated HFEs with lifetime < 20 years HG - 02 1 - (Difluoromethoxy) - 2 - (2 - (difluoromethoxy) - 1,1,2,2 - tetrafluoroethoxy) - 1,1,2,2 - tetrafluoroethane 205367 - 61 - 9 HF 2 C - (OCF 2 CF 2 )2 - OCF 2 H 2 , 730 CR 2f Saturated HFEs with lifetime < 20 years HG - 03 1,1,3,3,4,4,6,6,7,7,9,9,10,10,1 2,12 - Hexadecafluoro - 2,5,8,11 - tetraoxadodecane 173350 - 37 - 3 HF 2 C - (OCF 2 CF 2 ) 3 - OCF 2 H 2 , 850 CR 2f Saturated HFEs with lifetime < 20 years HG - 21 1,1,3,3,5,5,7,7,8,8,10,10 - Dodecafluoro - 2,4,6,9 - tetraoxadecane 249932 - 26 - 1 HF 2 C - OCF 2 CF 2 OCF 2 OCF 2 O CF 2 H 3 , 890 CR 2f Saturated HFEs with lifetime < 20 years 1 - Ethoxy - 1,1,2,2,3,3,3 - heptafluoropropane 22052 - 86 - 4 CF 3 CF 2 CF 2 OCH 2 CH 3 61 CR

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 20 of 25 Model Group Common or Trade Name Chemical Designation CAS No. Chemical Formula GWP GWP Source # 2f Saturated HFEs with lifetime < 20 years 1,1,2,2 - Tetrafluoro - 1 - (fluoromethoxy)ethane 37031 - 31 - 5 CH 2 FOCF 2 CF 2 H 871 CR 2f Saturated HFEs with lifetime < 20 years 1,1,2 - Trifluoro - 2 - (trifluoromethoxy) - ethane 84011 - 06 - 3 CHF 2 CHFOCF 3 1 , 240 CR 2f Saturated HFEs with lifetime < 20 years 1 - Ethoxy - 1,1,2,3,3,3 - hexafluoropropane 380 - 34 - 7 CF 3 CHFCF 2 OCH 2 CH 3 23 CR 2f Saturated HFEs with lifetime < 20 years Fluoro(methoxy)methane 460 - 22 - 0 CH 3 OCH 2 F 13 CR 2f Saturated HFEs with lifetime < 20 years Difluoro(methoxy)methane 359 - 15 - 9 CH 3 OCHF 2 144 CR 2f Saturated HFEs with lifetime < 20 years Fluoro(fluoromethoxy)methan e 462 - 51 - 1 CH 2 FOCH 2 F 130 CR 2f Saturated HFEs with lifetime < 20 years Difluoro(fluoromethoxy)meth ane 461 - 63 - 2 CH 2 FOCHF 2 617 CR 2f Saturated HFEs with lifetime < 20 years Trifluoro(fluoromethoxy)meth ane 2261 - 01 - 0 CH 2 FOCF 3 751 CR 2f Saturated HFEs with lifetime < 20 years HCFE - 235ca2 (enflurane) 2 - Chloro - 1 - (difluoromethoxy) - 1,1,2 - trifluoroethane 13838 - 16 - 9 CHF 2 OCF 2 CHFCl 583 + CR 2f Saturated HFEs with lifetime < 20 years HFE – 338mmz1 2 - (Difluoromethoxy) - 1,1,1,3,3,3 - hexafluoropropane 26103 - 08 - 2 (CF 3 ) 2 CHOCHF 2 380 AR4/Table A

- 1 2f Saturated HFEs with lifetime < 20 years 2 - Ethoxy - 3,3,4,4,5 - pentafluorotetrahydro - 2,5 - bis[1,2,2,2 - tetrafluoro - 1 - (trifluoromethyl)ethyl] - furan 920979 - 28 - 8 C 12 H 5 F 19 O 2 56 CR

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 21 of 25 Model Group Common or Trade Name Chemical Designation CAS No. Chemical Formula GWP GWP Source # 2e Saturated HFEs with lifetime > 20 years HFE - 236ca 1 - (Difluoromethoxy) - 1,1,2,2 - tetrafluoroethane 32778 - 11 - 3 CHF 2 OCF 2 CHF 2 4 , 240 CR 2e Saturated HFEs with lifetime > 20 years HFE – 134 1691 – 17 – 4 CHF 2 OCHF 2 6 , 320 AR4/Table A

- 1 2e Saturated HFEs with lifetime > 20 years HFE - 329me3 1,1,1,2,3,3 - Hexafluoro - 3 - (trifluoromethoxy)propane 428454 - 68 - 6 CF 3 CFHCF 2 OCF 3 4 , 550 CR 2e Saturated HFEs with lifetime > 20 years HFE – 125 3822 – 68 – 2 CHF 2 OCF 3 14 , 900 AR4/Table A

- 1 2e Saturated HFEs with lifetime > 20 years HG - 20 (Difluoromethoxy)((difluorom ethoxy)difluoromethoxy)diflu oromethane 249932 - 25 - 0 HF 2 C - (OCF 2 ) 2 - OCF 2 H 5 , 300 CR 2e Saturated HFEs with lifetime > 20 years HG - 30 1,1,3,3,5,5,7,7,9,9 - Decafluoro 2,4,6,8 - tetraoxanonane 188690 - 77 - 9 HF 2 C - (OCF 2 ) 3 - OCF 2 H 7 , 330 CR 2e Saturated HFEs with lifetime > 20 years 1,1,1,2,2,3,3 - Heptafluoro - 3 - (1,2,2,2 - tetrafluoroethoxy) - propane 3330 - 15 - 2 CF 3 CF 2 CF 2 OCHFCF 3 6 , 490 CR 2e Saturated HFEs with lifetime > 20 years 1,1' - Oxybis[2 - (difluoromethoxy) - 1,1,2,2 - tetrafluoroethane 205367 - 61 - 9 HCF 2 O(CF 2 CF 2 O) 2 CF 2 H 4 , 920 CR 2e Saturated HFEs with lifetime > 20 years 1,1,3,3,4,4,6,6,7,7,9,9,10,10,1 2,12 - hexadecafluoro - 2,5,8,11 - Tetraoxadodecane 173350 - 37 - 3 HCF 2 O(CF 2 CF 2 O) 3 CF 2 H 4 , 490 CR

2e Saturated HFEs with lifetime > 20 years 1,1,3,3,4,4,6,6,7,7,9,9,10,10,1 2,12,13,13,15,15 - eicosafluoro - 2,5,8,11,14 - Pentaoxapentadecane 173350 - 38 - 4 HCF 2 O(CF 2 CF 2 O) 4 CF 2 H 3 , 630 CR 3a Unsaturated PFC PFC C - 1418 Perfluorocyclopentene; Octafluorocyclopentene 559 - 40 - 0 c - C 5 F 8 1.97 * CR 3a Unsaturated PFC Dyneon HFP (3M) hexafluoropropylene (HFP); 116 - 15 - 4 C 3 F 6 , CF3CF=CF2 0.05 * CR

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 22 of 25 Model Group Common or Trade Name Chemical Designation CAS No. Chemical Formula GWP GWP Source # PFC - 1216; Perfluoropropene 3a Unsaturated PFC TFE tetrafluoroethylene (TFE); PFC - 1114; Perfluoroethene 116 - 14 - 3 CF 2 =CF 2 , C 2 F 4; 0.004 * CR 3a Unsaturated PFC Perfluorobuta - 1,3 - diene 685 - 63 - 2 CF 2 =CFCF=CF 2 0.003 * CR 3a Unsaturated PFC Perfluorobut - 1 - ene 357 - 26 - 6 CF 3 CF 2 CF=CF 2 0.10 * CR 3a Unsaturated PFC Perfluorobut - 2 - ene 360 - 89 - 4 CF 3 CF=CFCF 3 1.82 * CR 3b Unsaturated HFC HFC - 1234ze(Z) (Z) - 1,3,3,3 - Tetrafluoroprop - 1 - ene 29118 - 25 - 0 C 3 H 2 F 4 trans - CF 3 CH=CHF 0.29 * CR 3b Unsaturated HFC HFC - 1234ze(E) (E) - 1,3,3,3 - Tetrafluoroprop - 1 - ene 1645 - 83 - 6 C 3 H 2 F 4 cis - CF 3 CH=CHF 0.97 * CR 3b Unsaturated HFC TFP trifluoro propene (TFP); HFC 1243zf; 3,3,3 - Trifluoroprop - 1 - ene 677 - 21 - 4 C 3 H 3 F 3 , CF3CH=CH2 0.12 * CR 3b Unsaturated HFC VF vinyl fluoride (VF); HFC - 1141 75 - 02 - 5 C 2 H 3 F, CH 2 =CHF 0.02 * CR 3b Unsaturated HFC VF2 vinylidiene fluoride (VF2); HFC - 1132a 75 - 38 - 7 C 2 H 2 F 2 , CF 2 =CH 2 0.04 * CR 3b Unsaturated HFC HFC - 1234yf; HFO 1234yf 2,3,3,3 - Tetrafluoroprop - 1 - ene 754 - 12 - 1 C 3 H 2 F 4 CF3CF=CH2 0.31 * CR 3b Unsaturated HFC Capstone 42 - U perfluorobutyl ethene (42 - U); 3,3,4,4,5,5,6,6,6 - Nonafluorohex - 1 - ene 19430 - 93 - 4 C 6 H 3 F 9, CF 3 (CF 2 ) 3 CH=CH 2 0.16 * CR 3b Unsaturated HFC 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 C 8 H 3 F 13 , CF 3 (CF 2 ) 5 CH=CH2 0.11 * CR 3b Unsaturated HFC Capstone 82 - U perfluorooctyl ethene (82 - U); 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,1 0,10 - Heptadecafluorodec - 1 - ene 21652 - 58 - 4 C 10 H 3 F 17 , CF 3 (CF 2 ) 7 CH=CH 2 0.09 * CR 3b Unsaturated HFC Solstice 1233 zd(E) trans - 1 - chloro - 3,3,3 - trifluoroprop - 1 - ene 102687 - 65 - 0 C 3 H 2 ClF 3 , CHCl=CHCF 3 1.34 + CR

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 23 of 25 Model Group Common or Trade Name Chemical Designation CAS No. Chemical Formula GWP GWP Source # 3b Unsaturated HFC (E) - HFC - 1225ye (E) - 1,2,3,3,3 - Pentafluoroprop 1 - ene 5595 - 10 - 8 CF 3 CF=CHF(E) 0.06 * CR 3b Unsaturated HFC (Z) - HFC - 1225ye (Z) - 1,2,3,3,3 - Pentafluoroprop 1 - ene 5528 - 43 - 8 CF 3 CF=CHF(Z) 0.22 * CR 3b Unsaturated HFC (Z) - HFC - 1234ze (Z) - 1,3,3,3 - Tetrafluoroprop - 1 - ene 29118 - 25 - 0 CF 3 CH=CHF(Z) 0.29 * CR 3b Unsaturated HFC HFO - 1345zfc 3,3,4,4,4 - Pentafluorobut - 1 - ene 374 - 27 - 6 C 2 F 5 CH=CH 2 0.09 * CR 3b Unsaturated HFC (Z) - HFC - 1336 (Z) - 1,1,1,4,4,4 - Hexafluorobut 2 - ene 692 - 49 - 9 CF 3 CH=CHCF 3 (Z) 1.58 * CR 3c Unsaturated HFE PMVE, HFE - 216 perfluoromethyl vinyl ether (PMVE) 1187 - 93 - 5 CF 3 OCF=CF 2 0.17 * CR 3c Unsaturated HFE Fluoroxene (2,2,2 - Trifluoroethoxy)ethene 406 - 90 - 6 CF 3 CH 2 OCH=CH 2 0.05 * CR 3d Fluorinated Ketone Novec 1230 FK - 5 - 1 - 12 Perfluoroketone; FK - 5 - 1 - 12myy2; PERFLUORO(2 - METHYL - 3 - PENTANONE) 756 - 13 - 8 CF 3 CF 2 C(O)CF (CF 3 ) 2 0.11 * CR 4 Other Perfluorobutyl acetate 209597 - 28 - 4 CH 3 COOCF 2 CF 2 CF 2 CF 3 1.59 * CR 4 Other Perfluoropropyl acetate 1344118 - 10 - 0 CH 3 COOCF 2 CF 2 CF 3 1.78 * CR 4 Other Perfluoroethyl acetate 343269 - 97 - 6 CH 3 COOCF 2 CF 3 2.07 * CR 4 Other Trifluoromethyl acetate 74123 - 20 - 9 CH 3 COOCF 3 2.01 * CR 4 Other 1,1 - Difluoroethyl 2,2,2 - trifluoroacetate 1344118 - 13 - 3 CF 3 COOCF 2 CH 3 31 CR 4 Other Ethyl 2,2,2 - trifluoroacetate 383 - 63 - 1 CF 3 COOCH 2 CH 3 1.3 * CR 4 Other 2,2,2 - Trifluoroethyl 2,2,2 - trifluoroacetate 407 - 38 - 5 CF 3 COOCH 2 CF 3 7 CR 4 Other Methyl 2,2 - difluoroacetate 433 - 53 - 4 HCF 2 COOCH 3 3 CR 4 Other Difluoromethyl 2,2,2 - trifluoroacetate 2024 - 86 - 4 CF 3 COOCHF 2 27 CR 4 Other Methyl 2,2,2 - trifluoroacetate 431 - 47 - 0 CF 3 COOCH 3 52 CR 4 Other 3,3,3 - Trifluoropropan - 1 - ol 2240 - 88 - 2 CF 3 CH 2 CH 2 OH 0.35 * CR

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 24 of 25 Model Group Common or Trade Name Chemical Designation CAS No. Chemical Formula GWP GWP Source # 4 Other 4,4,4 - Trifluorobutan - 1 - ol 461 - 18 - 7 CF 3 (CH 2 ) 2 CH 2 OH 0.05 * CR 4 Other 2,2,3,3,4,4,4 - Heptafluorobutan - 1 - ol 375 - 01 - 9 C 3 F 7 CH 2 OH 34 CR 4 Other 2,2,3,3 - Tetrafluoro - 1 - propanol 76 - 37 - 9 CHF 2 CF 2 CH 2 OH 13 CR 4 Other 2,2,3,4,4,4 - Hexafluoro - 1 - butanol 382 - 31 - 0 CF 3 CHFCF 2 CH 2 OH 17 CR 4 Other 2,2,3,3,4,4,4 - Heptafluoro - 1 - butanol 375 - 01 - 9 CF 3 CF 2 CF 2 CH 2 OH 16 CR 4 Other 3,3,3 - Trifluoro - propanal 460 - 40 - 2 CF 3 CH 2 CHO 0.01 * CR 4 Other 2 - Fluoroethanol 371 - 62 - 0 CH 2 FCH 2 OH 1.07 * CR 4 Other 2,2 - Difluoroethanol 359 - 13 - 7 CHF 2 CH 2 OH 3 CR 4 Other 2,2,2 - Trifluoroethanol 75 - 89 - 8 CF 3 CH 2 OH 20 CR 4 Other Methyl carbonofluoridate 1538 - 06 - 3 FCOOCH 3 95 CR 4 Other 1,1 - Difluoroethyl carbonofluoridate 1344118 - 11 - 1 FCOOCF 2 CH 3 27 CR 4 Other Trifluoromethyl formate 85358 - 65 - 2 HCOOCF 3 588 CR 4 Other Perfluoroethyl formate 313064 - 40 - 3 HCOOCF 2 CF 3 580 CR 4 Other Perfluoropropyl formate 271257 - 42 - 2 HCOOCF 2 CF 2 CF 3 376 CR 4 Other Perfluorobutyl formate 197218 - 56 - 7 HCOOCF 2 CF 2 CF 2 CF 3 392 CR 4 Other 2,2,2 - Trifluoroethyl formate 32042 - 38 - 9 HCOOCH 2 CF 3 33 CR 4 Other 3,3,3 - Trifluoropropyl formate 1344118 - 09 - 7 HCOOCH 2 CH 2 CF 3 17 CR 4 Other 1,2,2,2 - Tetrafluoroethyl formate 481631 - 19 - 0 HCOOCHFCF3 470 CR 4 Other 1,1,1,3,3,3 - Hexafluoropropan 2 - yl formate 856766 - 70 - 6 HCOOCH(CF 3 ) 2 333 CR 4 Other Halon - 2311 / Halothane 2 - Bromo - 2 - chloro - 1,1,1 - trifluoroethane 151 - 67 - 7 CHBrClCF 3 41 + CR

### Analysis of Potential Default GWPs for Fluorinated GHGs Reported Under the GHGRP Page 25 of 25 # Sources for the GWPs include the IPCC Forth Assessment Report (AR4) (Forster, et al. 2007) , 7 Table A - 1 to subpart A of Part 9 8 published on October 30, 2009, 8 and the “Global Warming Potentials and Radiative Efficiencies of Halocarbons and Related Compounds: A Comprehensive Review ” (CR). + Chlorine - containing compound *Precise GWP calculated ^The GWP for this compound is different than the GWP in the version of Table A - 1 to Subpart A of Part 9 8 published on October 30, 2009.

7 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 Con stituents 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. 8 U.S. Environmental Protection Agency. 2009. Code of Federal Regulations. Table A - 1 to Subpart A of Part 98 – Global Warming Potent ials (100 - Year Time Horizon). October 30, 2009. Available at: http://www.epa.gov/ghgreporting/documents/pdf/2009/GHG

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