SUPPORTING ANALYSIS

FOR

MANDATORY REPORTING OF GREENHOUSE GASES: NOTICE OF PRELIMINARY 

DETERMINATIONS REGARDING REQUESTS TO USE PROVISIONAL GLOBAL 

WARMING POTENTIALS UNDER THE FLUORINATED GAS PRODUCTION 

CATEGORY OF THE GREENHOUSE GAS REPORTING RULE

Office of Air and Radiation

U.S. Environmental Protection Agency

January 23, 2011
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Table of Contents

Introduction...................................................................................................................................................3

Background...................................................................................................................................................3

Estimating Global Warming Potentials.........................................................................................................4

Summary of Information Submitted to EPA.................................................................................................6

Preliminary Determinations and Their Rationale .........................................................................................9
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Introduction

This Supporting Analysis provides background and rationale for the preliminary determinations 

regarding the provisional Global Warming Potentials (GWPs) for fluorinated greenhouse gases 

(GHGs) submitted to EPA by DuPont de Nemours, Inc. and Honeywell International for the 

purposes of the calculations in 98.123(c)(1) of subpart L—Fluorinated Gas Production of the 

Mandatory Reporting of Greenhouse Gases (40 CFR part 98).

Background

Under 98.123(c)(1), fluorinated gas producers that wish to use 98.123(c) (the Emission Factor 

Method or Emission Calculation Factor Method) to estimate emissions from a continuous 

process must make a preliminary estimate of the annual CO2e emissions of fluorinated GHGs 

from each process vent. They are required to do so using the engineering calculations or 

assessments specified in the rule. If the preliminary estimate indicates that a vent emits 10,000 

mtCO2e or more, facilities must use stack testing to establish an emission factor for that vent. If 

the preliminary estimate indicates that a vent emits less than 10,000 mtCO2e, facilities may use 

engineering calculations or assessments to establish an emission calculation factor.

Under 98.123(c)(1)(v), to convert the fluorinated GHG emissions to CO2e, fluorinated gas 

producers must use Equation A–1 of § 98.2. For fluorinated GHGs whose GWPs are not listed in 

Table A–1 to subpart A of part 98, producers must use a default GWP of 2,000 unless they

submit a request to use other GWPs for those fluorinated GHGs in that process under paragraph 

(c)(1)(vi), and EPA approves that request.

Under 98.123(c)(1)(vi), fluorinated gas producers may submit a request to use a GWP other than

2,000 for fluorinated GHGs whose GWPs are not listed in Table A–1 to subpart A if their 

process vent emits one or more fluorinated GHGs (1) whose GWPs are not listed in Table A–1 to 

subpart A, (2) that are emitted in quantities that, with a default GWP of 2,000, result in total 

calculated annual emissions equal to or greater than 10,000 metric tons CO2e for the vent, and

(3) that they believe have GWPs that would result in total calculated annual emissions less than 

10,000 metric tons CO2e.

Under 98.123(c)(1)(vi)(B), EPA reviews each request to determine whether it is complete, 

substantiates each of the provisional GWPs, and demonstrates that the process vents are 

calculated to emit less than 10,000 metric tons CO2e of fluorinated GHGs only when the 

proposed provisional GWPs, not the default GWP of 2,000, are used for the fluorinated GHGs 

for which the provisional GWPs are requested. If EPA makes a preliminary determination that 

each of these criteria is met, EPA publishes a notice for public comment including the

determination and the data and analysis submitted by the producers under paragraphs 

(c)(1)(vi)(A)(1) through (3).

Under paragraphs (c)(1)(vi)(A)(1) through (3), fluorinated gas producers must include the 

following information in the request for each fluorinated GHG that does not have a GWP listed 

in Table A–1 to subpart A of part 98 and that constitutes more than one percent by mass of the 

stream emitted from the vent:
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(1) The identity of the fluorinated GHG, including its chemical formula and, if available, 

CAS number.

(2) The estimated GWP of the fluorinated GHG.

(3) The data and analysis that supports the estimate of the GWP of the fluorinated GHG, 

including:

(i) Data and analysis related to the low-pressure gas phase infrared absorption 

spectrum of the fluorinated GHG.

(ii) Data and analysis related to the estimated atmospheric lifetime of the fluorinated 

GHG (reaction mechanisms and rates, including e.g., photolysis and reaction with 

atmospheric components such as OH, O3, CO, and water).

(iii) The radiative transfer analysis that integrates the lifetime and infrared absorption 

spectrum data to calculate the GWP.

(iv) Any published or unpublished studies of the GWP of the gas.

On February 25, 2011, Honeywell International (Honeywell) requested to use alternative GWPs 

for two fluorinated GHGs for the purposes of calculations in paragraph (c)(1) of 40 CFR 98.123. 

Honeywell requested to use alternate (i.e., lower) GWPs for two commercial chemicals produced 

at their Buffalo Research Laboratory: HFC-1234ze and HFC-1234yf. Honeywell included

published scientific papers and other information to fulfill the requirements under paragraphs 

(c)(1)(vi)(A)(1) through (3).

On February 28, 2011, E. DuPont de Nemours, Inc. (DuPont) requested to use alternative GWPs 

for six fluorinated GHGs for the purposes of calculations in paragraph (c)(1) of 40 CFR 98.123. 

DuPont requested to use alternate (i.e., lower) GWPs for six chemicals at DuPont plant sites 

subject to subpart L: hexafluoropropylene (HFP), perfluoromethyl vinyl ether (PMVE), 

tetrafluoroethylene (TFE), 3,3,3-trifluoropropene (TFP), vinyl fluoride (VF), and vinylidine 

fluoride (VF2). For each chemical, DuPont included peer-reviewed scientific data and other 

information to fulfill the requirements under paragraphs (c)(1)(vi)(A)(1) through (3).

Estimating Global Warming Potentials

For a compound that one knows will be a gas in the atmosphere and will absorb at infrared 

wavelengths, the key component of the Global Warming Potential (GWP) calculation is the 

integration of the radiative forcing for the compound over the 100-year integration time. In turn, 

the accuracy of the radiative forcing calculation depends on the scientific capabilities of the 

radiative transfer calculation, using the infrared absorption cross-sections for the compound 

being examined and the atmospheric lifetime of the compound (as a function of where it is 

emitted). The lifetime and radiative forcing are in turn affected by the compound’s distribution 

in the atmosphere with altitude, latitude and longitude.

Estimating GWPS depends on:

 Accurate knowledge of the reactivity of the compound to derive its lifetime and spatial 

distribution. For most compounds of interest this will depend on the compound’s rate of 

reaction with OH or rate of photolysis. Note that these can be strongly temperature 

dependent and for photolysis, can also be pressure dependent. Other reactants (e.g., 
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excited oxygen atoms, ozone, chlorine atoms) can be important, but are usually much less 

important.

 Accurate derivation of the lifetime of the compound. This means having a strong 

understanding of how temperatures and pressures vary spatially, especially with altitude, 

how atmospheric concentrations of OH vary spatially and over time (i.e., daily and 

seasonally), and in cases where photolysis is an important removal mechanism, a strong 

knowledge on the absorption cross-sections and the quantum yield as well as an accurate 

derivation of the photolysis rates spatially. The spatial and temporal variation in 

atmospheric concentrations for other reactants is also important if reactions with those 

gases are relevant.

 Accurate knowledge of the spatial distribution of the compound, and its emissions, with 

latitude, longitude and altitude. Long-lived gases are generally well mixed, especially in 

the troposphere, but short-lived gases are not well-mixed in either the troposphere or the 

stratosphere. (Short-lived gases simply do not last long enough to become well mixed.)

This is especially important for the radiative forcing analysis but can also be very 

relevant to the lifetime derivation.

 Accurate knowledge of the infrared absorption cross-sections. These can either be 

obtained from laboratory measurements or from ab initio theoretical approaches. In 

practice, if only a very roughly estimated GWP is needed, one can approximate to 

another compound with similar chemical structure.

 Accurate knowledge of the radiative forcing of the compound, which requires an accurate 

radiative transfer modeling capability that represents the effects of the atmospheric 

distribution of temperature, pressure, clouds, water vapor, ozone and other key 

constituents. It must also consider possible overlaps of the cross-sections with those for 

other gases and particles in the background atmosphere.

The most accurate approach to derive a GWP is to use a full three-dimensional model of the 

global atmosphere where emissions are assumed at the locations of interest for the derived 

GWPs. These studies are computationally expensive. To get around this, alternative estimation 

approaches have been developed. However, these alternative approaches typically assume that 

the gases are well mixed in the atmosphere (that is, distributed evenly over all longitudes, 

latitudes, and altitudes). These approaches therefore do not fully reflect the radiative behavior of 

gases that are not well mixed, such as short-lived gases. While the methods themselves allow for 

a radiative forcing analysis that accounts for variation with altitude, in practice, a number of 

physical chemists who have estimated GWPs assume that the gas is well mixed with altitude. 

While this is never a completely accurate assumption except for extremely long-lived gases 

(lifetime much greater than 200 years), the assumption is particularly inaccurate for short-lived 

compounds, that is, compounds with lifetimes of less than a year. This issue is discussed in more 

detail by Patten et al. (2011).1

 1 K. O. Patten, V. G. Khamaganov, V. L. Orkin, S. L. Baughcum, and D. J. Wuebbles, 2011, OH reaction rate 

constant, IR absorption spectrum, ozone depletion potentials and global warming potentials of 2-bromo-3,3,3-

trifluoropropene, Journal of Geophysical Research 116: D24307, doi:10.1029/2011JD016518.
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Summary of Information Submitted to EPA

On February 25, 2011, Honeywell International (Honeywell) requested to use alternative GWPs 

for fluorinated GHGs for the purposes of calculations in paragraph (c)(1) of 40 CFR 

98.123(c)(1). Honeywell requested to use alternate (i.e., lower) GWPs for two commercial 

chemicals produced at their Buffalo Research Laboratory: HFC-1234ze (CAS # 29118-24-9)

(CF3CH=CHF)

2 and HFC-1234yf (CAS # 754-12-1) (CF3CF=CH2).3 Honeywell included 

published scientific papers and other information to fulfill the requirements requested under 

paragraphs (c)(1)(vi)(A)(1) through (3).

Honeywell provided three scientific papers (and other materials referencing the results of these 

studies published by EPA) to fulfill the requirements under 98.123(c)(1)(vi)(A)(1) through (3):

(1) Vassileios C. Papadimitriou, Ranajit K. Talukdar, R. W. Portmann, A. R. Rabvishankara, 

and James B. Burkholder, 2008, CF3CF=CH2 and (Z)-CF3CF=CHF: temperature 

dependent OH rate coefficients and global warming potentials, Physical Chemistry 

Chemical Physics 10:808–820.

(2) R. Søndergarrd, O. J. Nielsen, M. D. Hurley, T.J. Wallington, and R. Singh, 2007, 

Atmospheric chemistry of trans-CF3CH=CHF: Kinetics of the gas-phase reactions with 

Cl atoms, OH radicals, and O3, Chemical Physical Letters 443:199–204.

(3) O. J. Nielsen, M. S. Javadi, M. P. Sulbaek, M. D. Hurley, T.J. Wallington, and R. Singh, 

2007, Atmospheric chemistry of CF3CF=CH2: Kinetics and mechanisms of gas-phase 

reactions with Cl atoms, OH radicals, and O3, Chemical Physical Letters 439:18–22.

Papadimitriou et al. (2008) estimate that the GWP of HFC-1234yf (CF3CF=CH2) is less than 4.4, 

based on a 100 year time horizon, compared to value of 1 for carbon dioxide (CO2), and using 

the infrared absorption cross-sections measured in their study. In addition, they also estimate that 

that HFC-1234yf has an estimated local atmospheric lifetime of 12 days based solely on OH 

reactive loss. However, the authors acknowledge that the constant mixing profiles of HFC1234yf assumed in the GWP calculation is likely to overestimate the radiative efficiency of the 

short-lived compound; and therefore, the GWP estimate should be taken as an upper estimate.

Similarly, Nielsen et al. (2007) estimate that HFC-1234yf (CF3CF=CH2) has an atmospheric 

lifetime of approximately 11 days with respect to reaction with OH radicals, and a GWP of 4, 

based on a 100 year time horizon, compared to value of 1 for carbon dioxide (CO2). However, 

the authors acknowledge that the quoted lifetime is a global average, and the local lifetimes 

could be significantly shorter or longer. The authors subsequently use this quoted lifetime and 

the scaling method outlined by Pinnock et al. (1995) to estimate the GWP.4 Again, the approach 

used is likely to lead to an overestimate of the actual GWP values.

 2 HFC-1234ze (CAS # 29118-24-9) is also known as trans-1,3,3,3-tetrafluoroprop-1-ene (CF3CH=CHF)

3 HFC-1234yf (CAS # 754-12-1) is also known as 2,3,3,3-tetrafluoroprop-1-ene (CF3CF=CH2).

4 S. Pinnock, M. D. Hurley, K. P. Shine, T. J. Wallington, and T. J. Smyth, 1995, J. Geophys. Res. 100:23227.
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By comparison, Søndergarrd et al. (2007) estimate that HFC-1234ze (CF3CH=CHF) has an 

atmospheric lifetime of approximately 2 weeks with respect to reaction with OH radicals, and a 

GWP of approximately 6, based on a 100 year time horizon, compared to value of 1 for carbon 

dioxide (CO2). A number of the co-authors (O. J. Nielsen, M. D. Hurley, T.J. Wallington, and R. 

Singh) of the Nielsen et al. (2007) paper are also co-authors of the Søndergarrd et al. (2007) 

paper, and similar methods to those previously described were used to estimate the atmospheric 

lifetime and GWP values.

On June 27, 2011, E. DuPont de Nemours, Inc. (DuPont) requested to use alternative GWPs for 

fluorinated GHGs for the purposes of calculations in paragraph (c)(1) of 40 CFR 98.123(c)(1). 

DuPont requested to use alternate (i.e., lower) GWPs for six chemicals at DuPont plant sites 

subject to subpart L: hexafluoropropylene (HFP) (CAS # 116-15-4), perfluoromethyl vinyl ether 

(PMVE) (CAS # 1187-93-5), tetrafluoroethylene (TFE) (CAS # 116-14-3), 3,3,3-

trifluoropropene (TFP) (CAS # 677-21-4), vinyl fluoride (VF) (CAS # 75-02-5), and vinylidine 

fluoride (VF2) (CAS # 75-38-7). For each chemical, DuPont included peer-reviewed scientific 

data and other information to fulfill the requirements requested under paragraphs (c)(1)(vi)(A)(1) 

through (3).

For hexafluoropropylene (HFP) and tetrafluoroethylene (TFE), DuPont referred to a study 

conducted by Acerboni et al. (2001),5 which estimated the global and yearly averaged lifetime as 

6 days for HEP and 1.9 days for TFE, and a GWP of 0.25 for HEP and 0.021 for TFE, both 

based on a 100 year time horizon, compared to value of 1 for carbon dioxide (CO2). The study 

applied a chemical transport model to estimate the atmospheric distributions and lifetime, and 

radiative forcing calculations were performed using a radiative transfer model assuming either 

constant vertical concentration profiles or the distributions derived from the chemical transport 

model.

For perfluoromethyl vinyl ether (PMVE), DuPont referred to a study conducted by Mashino et 

al. (2000),6 which estimated the global and yearly averaged lifetime as 8 days with respect to 

reaction with OH, and a GWP of 2, based on a 100 year time horizon, compared to value of 1 for 

carbon dioxide (CO2). The study estimated the atmospheric lifetime by scaling to the know 

lifetime of methyl chloroform, and radiative forcing calculations were performed using the 

approximation method developed by Pinnock et al. (1995).4

For 3,3,3-trifluoropropene (TFP), DuPont referred to a study conducted by Anderson et al. 

(2005),7 which estimated the overall global and yearly averaged lifetime as 7.0 days with respect 

to reaction with OH and O3, and a GWP of 3, based on a 100 year time horizon, compared to 

value of 1 for carbon dioxide (CO2). The study estimated the atmospheric lifetime by assuming 

 5 G. Acerboni, et al., 2001, Atmospheric degradation and global warming potentials of three perfluoroalkenes,

Atmospheric Environment 35(24): 4113–4123.

6 M. Mashino, et al., 2000, Atmospheric Degradation of CF3OCFCF2: Kinetics and Mechanism of Its Reaction with 

OH Radicals and Cl Atoms, The Journal of Physical Chemistry A 104(13): 2925–2930.

7 M. P. S. Andersen, et al., 2005, Atmospheric chemistry of CxF2x+1CH=CH2 (x=1, 2, 4, 6, and 8): Kinetics of gasphase reactions with Cl atoms, OH radicals, and O3, Journal of Photochemistry and Photobiology, A: Chemistry, 

176(1–3):124–128.
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global weighted average concentrations of OH and O3, and radiative forcing calculations were 

performed using the approximation method developed by Pinnock et al. (1995).4

For vinyl fluoride (VF) and vinylidine fluoride (VF2), DuPont referred to a study conducted by 

Baasandorj et al. (2010),8 which estimated the overall global and yearly averaged lifetime as 2 

days for VF and 4 days for VF2, both with respect to reaction with OH, and a GWP of 0.7 for VF 

and 0.9 for VF2, both based on a 100 year time horizon, compared to value of 1 for carbon 

dioxide (CO2). Radiative forcing calculations were performed using the approximation method 

developed by Pinnock et al. (1995).4

In addition, DuPont included information on three additional chemicals whose calculated 

emission rates, using a GWP of 2000, do not currently equal or exceed 10,000 mtCO2e for any

vent, but may in the future: carbonyl fluoride (CAS # 353-50-4), perfluoropropyl vinyl ether 

(CAS # 1623-05-8), and perfluoroethyl vinyl ether (CAS # 10493-43-3).

For carbonyl fluoride, DuPont referred to a study conducted by Kanakidou et al. (1995),9 which 

estimated the overall global and yearly averaged lifetime to lie in the range of 3.9 to 7.1 days, 

and a GWP of 2, based on a 100 year time horizon, compared to value of 1 for carbon dioxide 

(CO2). The study estimated the atmospheric lifetime by embedding experimentally determined 

Henry’s law coefficients and hydrolysis rate constants into a global tropospheric chemical 

transport model, and radiative forcing calculations were performed using the approximation 

method developed by Pinnock et al. (1995).4

For perfluoropropyl vinyl ether, DuPont estimated the overall global and yearly averaged 

lifetime as 8.077 days, and a GWP of 3, based on a 100 year time horizon, compared to value of 

1 for carbon dioxide (CO2). The atmospheric lifetime was estimated using the AOPWIN module 

of EPA’s EPI SuiteTM v4.10 exposure assessment modeling tool, and radiative forcing 

calculations were performed using the approximation method developed by Pinnock et al. 

(1995).4

For perfluoroethyl vinyl ether, DuPont estimated the overall global and yearly averaged lifetime 

as 8.077 days, and a GWP of 3, based on a 100 year time horizon, compared to value of 1 for 

carbon dioxide (CO2). The atmospheric lifetime was again estimated using the AOPWIN module 

of EPA’s EPI SuiteTM v4.10 exposure assessment modeling tool, and radiative forcing 

calculations were again performed using the approximation method developed by Pinnock et al. 

(1995).4

The GWP values for all of the compounds discussed above are all likely to be upper limits 

because of the assumption in the derivations that the gases are well mixed .

 8 M. Baasandorj, et al., 2010, Rate Coefficients for the Gas-Phase Reaction of the Hydroxyl Radical with 

CH2═CHF and CH2═CF2. The Journal of Physical Chemistry A 114(13): 4619–4633.

9 M. Kanakidou, F.J. Dentener, and P.J. Crutzen, 1995, A global three-dimensional study of the fate of HCFCs and 

HFC-134a in the troposphere, Journal of Geophysical Research 100(D9).
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Preliminary Determinations and Their Rationale

In accordance with 98.123(c)(1)(vi)(B), EPA reviewed the requests from both Honeywell and 

DuPont to determine whether each was complete, substantiated each of the provisional GWPs, 

and demonstrated that the process vents were calculated to emit less than 10,000 metric tons 

CO2e of fluorinated GHGs only when the proposed provisional GWPs, not the default GWP of 

2,000, were used for the fluorinated GHGs for which the provisional GWPs were requested. 

EPA made a preliminary determination that each of these criteria was met for the requests 

submitted by both Honeywell and DuPont, with one exception. (The exception was for HFC1234yf , which was emitted in quantities that, with a default GWP of 2,000, resulted in total 

calculated annual emissions of less than10,000 mtCO2e.) The remainder of this section includes 

a summary of the determination and the data and analysis submitted by the producers under 

paragraphs (c)(1)(vi)(A)(1) through (3).

EPA’s preliminary determination included review of the submitted information by a leading 

subject matter expert on GWP estimation who was also a co-developer of the GWP concept. 

EPA concluded that the methods overall were likely to overestimate GWPs (maybe by an order 

of magnitude or more) rather than underestimate them. Because 98.123(c)(1) allows the use of 

engineering calculations only when estimated emissions fall below 10,000 metric tons CO2e, an 

overestimated GWP is considered acceptable by EPA in the context of 98.123(c)(1). Therefore, 

the conclusion of EPA’s review was that the background information was adequate and that it 

justified the use of the alternative GWPs in the context of 98.123(c)(1)(vi).

The overestimation of the GWPs submitted by both Honeywell and DuPont results from the fact 

that the commonly-used estimation techniques employed in the analyses cited by both companies 

use simplifying assumptions that are not fully applicable to compounds that are short-lived in the 

atmosphere—defined here as any compound with an atmospheric lifetime less than 1 year. (All 

of the compounds for which provisional GWPs were requested are short-lived based on this 

definition.) Essentially, the estimation techniques assume that the compounds are well-mixed in 

the atmosphere, but short-lived compounds do not last long enough to become well mixed (i.e., 

spread evenly over all longitudes, latitudes, and altitudes). Instead, their concentrations decrease 

rapidly with distance from their emission point, particularly with changing latitude and altitude.

The assumption that the compounds are well mixed affects the estimates of both of the primary 

components of GWPs: atmospheric lifetime and radiative forcing. In the analyses cited by the 

companies, atmospheric lifetimes are estimated either by assuming that the short-lived 

compound is exposed to the global average concentration of hydroxyl radicals (OH), or by

deriving the lifetime of the short-lived (i.e., not well-mixed) compound from the known lifetime 

of a long-lived (i.e., well-mixed) reference compound based on the compounds’ respective 

reaction rates with OH. Both approaches are likely to overestimate the lifetime (and therefore the 

GWP) of the short-lived compound because they essentially assume that the concentration of the 

short-lived compound remains constant with altitude. This overestimates the share of the shortlived compound that resides higher in the atmosphere, where lower OH concentrations, 

temperatures, and pressures slow reaction rates and lengthen lifetimes. Radiative forcing is also 

estimated based on the assumption that the concentration of the short-lived compound remains 

constant with altitude. This assumption is likely to overestimate the radiative forcing (and 
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therefore the GWP) of short-lived compounds because, again, it overestimates the share of the 

short-lived compound that resides higher in the atmosphere. GHGs higher in the atmosphere 

(i.e., near the tropopause) are responsible for more radiative forcing than the same GHGs lower 

in the atmosphere. Radiative forcing is most sensitive to GHG changes in the vicinity of the 

tropopause, where the atmospheric temperature minimum occurs. These expectations are born 

out in radiative transfer calculations where it is found that radiative forcing is most sensitive to 

concentration changes at the tropopause level. Together, these assumptions may result in 

overestimates of the GWP by a factor of ten or more.

The provisional GWPs are shown in Table 1.

Table 1: Provisional Global Warming Potentials for fluorinated greenhouse gases for 

which EPA has made preliminary determinations that all approval criteria have been met 

for the purposes of the calculations in 98.123(c)(1) of subpart L.

Fluorinated GHG CAS # Provisional GWP

HFC-1234ze 29118-24-9 6

hexafluoropropylene (HFP) 116-15-4 0.25

perfluoromethyl vinyl ether (PMVE) 1187-93-5 3

tetrafluoroethylene (TFE) 116-14-3 0.02

trifluoro propene (TFP) 677-21-4 3

vinyl fluoride (VF) 75-02-5 0.7

vinylidine fluoride (VF2) 75-38-7 0.9

As noted above, DuPont also included provisional GWPs and data and analysis for three other 

fluorinated GHGs, including carbonyl fluoride (CAS # 353-50-4), perfluoropropyl vinyl ether 

(CAS # 1623-05-8), and perfluoroethyl vinyl ether (CAS # 10493-43-3). Dupont noted that the 

calculated emissions of these chemicals from particular process vents did not currently exceed 

10,000 metric tons of CO2e, but may exceed 10,000 metric tons CO2e in the future. In response 

to these submissions and to Honeywell’s submission of a provisional GWP and data and analysis 

for HFC-1234yf , EPA noted that it would consider the information as Table A-1 of 40 CFR Part 

98 is updated.