United States Air and Radiation EPA420-F-00-001
Environmental Protection April 2000
Agency
vxEPA MOBILES Information
Sheet #8
Tier 2 Benefits Using
MOBILES
> Printed on Recycled Paper
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EPA420-F-00-001
April 2000
#8
Tier 2
Assessment and Standards Division
Office of Air Transportation and Air Quality
U.S. Environmental Protection Agency
NOTICE
This technical report does not necessarily represent final EPA decisions or positions.
It is intended to present technical, analysis of issues using data, which are currently available.
The purpose in the release of such reports is to facilitate the exchange of
technical information and to inform the public of technical developments which
may form the basis for a final EPA decision, position, or regulatory action.
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EPA420-F-00-001
>
MOBILES
Information Sheet #8
%^£/ Tier 2 Benefits Using MOBILES
April 2000
US EPA, NVFEL, ASD, 2000 Traverwood, Ann Arbor, Michigan 48105 (734) 214-4902
I. Introduction
MOBILES Information sheets are a series of documents intended to give users detailed
information about techniques that can be used to more accurately model highway mobile source
emissions and avoid potential errors or resolve limitations to modeling capabilities. When
referring to MOBILES in this and other Information Sheets, we will mean the latest officially
released version of the MOBILE model, unless otherwise specifically noted. At the time of this
Information Sheet, two versions of the model were actively being used. The most current version
of the model, MOBILESb, was released in October of 1996 while the other version, MOBILESa,
was released in March of 1993.
All of the MOBILES Information Sheets will be made available on the EPA Office of
Transportation and Air Quality site on the World Wide Web (WWW). The WWW site is
available to users 24 hours a day, 7 days a week, and may be reached at
"http://www.epa.gov/oms/m5.htm".
If you would like to be added to our mailing list, please follow the instructions included
in the last section of the Information Sheet. This only need be done once. You do not need to
send in this information if you are already on our mailing list.
II. Problem Description
The final rule on Tier 2 Motor Vehicle Emissions Standards and Gasoline Sulfur Control
Requirements ("Tier 2 standards") for passenger cars, light trucks, and larger passenger vehicles
was published on February 10, 2000 (65 FR 6698). The program is designed to focus on
reducing the emissions most responsible for the ozone and particulate matter (PM) impact from
these vehicles — nitrogen oxides (NOx) and non-methane organic gases (NMOG), consisting
primarily of hydrocarbons (HC) and contributing to ambient volatile organic compounds (VOC).
MOBILES Information Sheet #8 April 2000
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The program will also, for the first time, apply the same set of federal standards to all passenger
cars, light trucks, and medium-duty passenger vehicles. Light trucks include "light light-duty
trucks" (or LLDTs), rated at less than 6000 pounds gross vehicle weight and "heavy light-duty
trucks" (or HLDTs), rated at more than 6000 pounds gross vehicle weight). "Medium-duty
passenger vehicles" (or MDPVs) form a new class of vehicles introduced by this rule that
includes SUVs and passenger vans rated at between 8,500 and 10,000 GVWR. The program thus
ensures that essentially all vehicles designed for passenger use in the future will be clean
vehicles. More information about this rule is available on the EPA web site:
http://www.epa.gov/oms/tr2home.htm
MOBILESa and MOBILESb were released in 1993 and 1996, respectively, before the
Tier 2 rules were proposed. As a result, MOBILESa and MOBILESb did not address the effects
of Tier 2 exhaust and evaporative emission certification requirements on emissions for motor
vehicles starting in 2004. These effects will be addressed in the MOBILE6 on-road emissions
model, planned for release at the end of 2000. However, there are many areas which wish to
include the effects of the Tier 2 standards in SIPs and conformity analyses before MOBILE6 is
available.
III. Remedy
Background
The effect of Tier 2 on emission inventories was estimated for 1-hour ozone attainment
demonstration areas in a memorandum, "1-Hour Ozone Attainment Demonstrations and Tier
2/Sulfur Rulemaking" from Lydia N. Wegman, Director, Air Quality Standards and Standards
Division of the Office of Air Quality Planning and Standards and Merrylin Zaw-Mon, Director,
Fuels and Energy Division of the (then) Office of Mobile Sources to the Air Directors of EPA
Regions 1-6, dated November 8, 1999. The purpose of the memo was to advise the EPA
Regional offices of the relationship between 1-hour ozone attainment demonstrations and the
emissions reductions that will be achieved by the Tier 2/sulfur (Tier 2) rule and to provide
emissions data related to that rule. This information assist the Regions in their work with States
on issues related to the 1-hour ozone attainment demonstrations and the benefits of the Tier 2
rule for certain serious and severe ozone nonattainment areas in those Regions. A copy of this
memo and the associated spreadsheet is available on the EPA web site at:
http://www.epa.gov/ttncaaal/tl/meta/ml0433.html
EPA stated in the November 8, 1999 memorandum that an official MOBILE information
sheet would be released to provide guidance on crediting Tier 2 standards in SIPs and
conformity. This information sheet provides that guidance.
The November 8, 1999 memorandum was meant originally to address only the immediate
needs of certain ozone nonattainment areas and only addresses the impact of Tier 2 on SIP
MOBILES Information Sheet #8 2 April 2000
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inventories. This MOBILE information sheet is intended to make this information more widely
available to other areas that may have a need for this information. States that have already
submitted SIP revisions based on the November 8, 1999 memorandum do not need to revise
those SIPs with this information sheet. SIP and conformity implementers must use this
information sheet to assess the emission reductions associated from the Tier 2 program in future
emissions analyses.
Users of the information given here and in the November 8, 1999 memorandum need to
be aware of the serious limitations of this information in certain situations. The model used to
derive these estimates of Tier 2 reductions incorporates changes proposed for MOBILE6 that are
unrelated to the Tier 2 program and, as a result, produces baseline emissions estimates that are
different from those produced by MOBILES. In the absence of MOBILE6, users will apply these
reductions to baseline emissions calculated using versions of MOBILES. As a result, the final
inventories estimated using this method may be substantially different from what will be
estimated once MOBILE6 becomes available.
After applying the reduction estimates given here and in the November 8, 1999 memo,
areas using some combinations of local inputs may derive inventory estimates that are
unreasonable, because of the differences in the model used to derive these reduction estimates
and the MOBILES model used to derive baseline emissions in local areas. These areas should
contact Gary Dolce at (734) 214-4414 or dolce. gary@ epa.gov for further guidance.
The final rule on Tier 2 Motor Vehicle Emissions Standards and Gasoline Sulfur Control
Requirements does not claim or estimate specific benefits from the rule for CO emissions. As a
result, this User Information Sheet will not present an estimate of the effect of the Tier 2
standards on CO emissions. The effect of the Tier 2 rule on all emissions (including CO
emissions) will be included in the MOBILE6 version of the model when it becomes available.
Method
Tables 1 through 6 for VOC and NOx reductions in this information sheet were
distributed with the November 8, 1999 memorandum (referred to in that memorandum as Tables
8 and 9). These tables give differences in base case and control case emission factors for VOC
and NOx for six different combinations of inspection/maintenance [I/M] program and gasoline
formulation for calendar years from 2004 to 2030. Reductions are shown for gasoline fueled
passenger cars (LDGV), light-duty trucks (LDGT) and heavy duty vehicles (>8500 Ibs GVWR)
and for diesel fueled light-duty trucks (LDDT). The estimate for reductions for diesel fueled
passenger vehicles, heavy duty trucks and for motorcycles are negligible and are not shown.
The differences were derived from the special version of MOBILE called "Modified
MOBILE5b/Version2," prepared for the Tier 2 rulemaking. Full documentation of the methods
used to develop the estimates for VOC and NOx are available in the Tier 2 Docket. To briefly
summarize here, highway vehicle emissions were first estimated using MOBILESb with input
files that described specific conditions (I/M program, temperatures, fuel parameters, registration
MOBILES Information Sheet #8 3 April 2000
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distribution). The resulting emission factors were then multiplied by correction factors in order
to simulate emission factors that would result from proposed changes in MOBILE to be
incorporated in MOBILE6. Correction factors were developed for both a base case (without Tier
2 control) and a Tier 2 control case. Because the factors used were based on default national
MOBILE inputs and for the reasons described above, the results should be viewed as interim
approximations which may change substantially when MOBILE6 becomes available. The
accuracy of the resulting estimated emission reductions for specific areas is further limited by the
lack of local area specificity in the MOBILE inputs used to develop the emission factors for these
tables. For example, the emission reductions would be greater in an area that has greater fleet
turnover (i.e., the fleet age distribution has a higher percentage of newer vehicles) than the
default, national average distribution used in MOBILE.
The differences in grams per mile shown in the tables can be multiplied by the
appropriate local VMT to develop rough estimates of Tier 2 reductions in any area in any year
starting in 2004. These Tier 2 reductions would then be subtracted from the total motor vehicle
emissions that were calculated using MOBILESa or MOBILESb and existing MOBILE
information sheets. Areas wishing to use the tables must choose the table that best fits their own
local conditions. Table 7 shows some detail regarding the specific inputs used to define the I/M
program and other important parameters used to derive the reductions. Further detail about the
inputs used can be found in the Tier 2 docket. Areas may wish to consult with their EPA
Regional office for advice on which tables to use.
MOBILES is an area-wide model and the results are best applied area-wide. However,
once the area-wide benefits have been determined, a proportional reduction (i.e., area-wide
percent reduction) can be determined and used for more detailed link-based analysis.
EPA understands the limitations of this information and the resulting inaccuracy in
inventory estimates. However, a more detailed analysis will be possible when MOBILE6
becomes available. These tables should not be used with emission estimates based on versions
of MOBILE which have already been modified to account for changes in the basic emission rates
as the result of introduction of Tier 2 vehicles into the fleet.
IV. Additional Information/ Listserver Subscription
EPA Office of Transportation and Air Quality (OTAQ) sponsors a listserver named
EPA-MOBILENEWS. A listserver is an electronic mailing list service that will send messages
to the all of the persons with e-mail addresses who have "subscribed" to that particular listserver.
This listserver has largely replaced physical mailings of information to parties interested in the
MOBILE model, as well as others interested in general mobile source emission factor and
inventory information (including particulate emissions and the PART emission factor model, and
nonroad mobile sources).
To subscribe to the EPA-MOBILENEWS listserver send the following message:
MOBILES Information Sheet #8 4 April 2000
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subscribe EPA-MOBILENEWS FIRSTNAME LASTNAME
where FIRSTNAME and LASTNAME is your name (for example: Fred Flintstone) to the EPA
List server address. The list server e-mail address is:
li stserver@unixmail. rtpnc. epa.gov
Your e-mail address will then be added to the list of subscribers and a confirmation
message will be sent to your e-mail address. Whenever a message is posted to the
EPA-MOBILENEWS listserver by the listserver owner (The Assessment and Standards Division
of the EPA's Office of Transportation and Air Quality), a copy of that message will be sent to
every person who has subscribed.
You can remove yourself from the list by sending another message to the listserver
address. This message must be sent from the same e-mail address that you used to subscribe, and
must contain the message:
unsubscribe EPA-MOBILENEWS
If you are interested in highway vehicle emission factors, including particulate matter, the
MOBILE and PART emission factor models, and non-road vehicle emission factors and
modeling, as well as guidance issued from OTAQ on the use of these models and development of
emission inventories for all mobile sources, the Assessment and Standards Division encourages
you to take advantage of the EPA-MOBILENEWS listserver as the best and most efficient way
to get up-to-date information about these issues.
We recognize that some parties interested in these topics may not be able to subscribe to
the listserver, and we will continue to mail paper copies of information to those parties on
request. If you cannot subscribe to the EPA-MOBILENEWS listserver at this time and wish to
continue to receive paper copies of information by regular mail, please mail or fax your current
information (name, company name, mailing address, phone and fax numbers) to us at the address
below and clearly indicate that you wish to continue receiving paper copies of all information
distributed over the listserver. Send this request to:
MOBILE/PART Mailing Lists
US EPA NVFEL
Assessment and Standards Division
2000 Traverwood
Ann Arbor, MI 48105
or fax the information to: 734/214-4939
and note "Attention: MOBILE/PART Mailing Lists" on the fax.
MOBILES Information Sheet #8 5 April 2000
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Table 1
Difference in Hydrocarbon Emissions (grams per mile) Due to Tier 2/Sulfur Program
with No I/M Programs
Conventional Gasoline Reformulated Gasoline
Calendar
Year
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
LDGV
0.047
0.046
0.046
0.046
0.047
0.047
0.048
0.048
0.048
0.050
0.051
0.051
0.053
0.054
0.055
0.056
0.057
0.058
0.058
0.058
0.058
0.059
0.060
0.059
0.059
0.059
0.060
LDGT
<6001 Ibs.
0.063
0.059
0.056
0.060
0.059
0.052
0.053
0.056
0.058
0.057
0.058
0.059
0.061
0.062
0.062
0.063
0.063
0.064
0.065
0.064
0.064
0.065
0.065
0.065
0.066
0.066
0.065
LDGT
>6000 Ibs.
0.086
0.096
0.108
0.139
0.150
0.147
0.165
0.183
0.199
0.214
0.228
0.241
0.252
0.264
0.273
0.282
0.290
0.297
0.302
0.308
0.313
0.317
0.319
0.326
0.331
0.333
0.334
LDDT
0.052
0.124
0.190
0.250
0.301
0.345
0.381
0.412
0.437
0.459
0.475
0.488
0.499
0.508
0.515
0.520
0.524
0.527
0.529
0.530
0.532
0.533
0.534
0.535
0.536
0.537
0.532
HDGV
0.110
0.100
0.090
0.082
0.071
0.060
0.055
0.050
0.045
0.042
0.039
0.038
0.037
0.035
0.034
0.033
0.032
0.030
0.026
0.023
0.021
0.018
0.016
0.013
0.011
0.010
0.009
LDGV
0.020
0.020
0.020
0.021
0.023
0.025
0.026
0.029
0.030
0.032
0.033
0.035
0.036
0.038
0.039
0.040
0.041
0.042
0.042
0.042
0.044
0.044
0.044
0.044
0.044
0.045
0.044
LDGT
<6001 Ibs.
0.022
0.023
0.024
0.026
0.029
0.032
0.035
0.038
0.041
0.044
0.046
0.049
0.051
0.052
0.054
0.054
0.054
0.055
0.056
0.056
0.056
0.056
0.057
0.057
0.057
0.058
0.058
LDGT
>6000 Ibs.
0.031
0.040
0.051
0.065
0.080
0.095
0.111
0.125
0.139
0.153
0.165
0.176
0.186
0.195
0.203
0.210
0.217
0.222
0.228
0.233
0.236
0.240
0.243
0.249
0.253
0.255
0.255
LDDT
0.055
0.130
0.200
0.265
0.321
0.368
0.408
0.442
0.469
0.492
0.510
0.524
0.536
0.545
0.553
0.559
0.564
0.567
0.569
0.571
0.573
0.575
0.576
0.578
0.579
0.580
0.575
HDGV
0.040
0.038
0.036
0.034
0.030
0.027
0.025
0.023
0.021
0.020
0.020
0.020
0.019
0.020
0.019
0.019
0.019
0.018
0.016
0.014
0.013
0.012
0.011
0.010
0.008
0.008
0.007
MOBILES Information Sheet #8
April 2000
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Table 2
Difference in Hydrocarbon Emissions (grams per mile) Due to Tier 2/Sulfur Program
with Phase-In I/M Programs
Conventional Gasoline
Reformulated Gasoline
Calendar
Year
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
LDGV
0.044
0.044
0.044
0.045
0.046
0.046
0.048
0.049
0.050
0.051
0.052
0.054
0.055
0.057
0.057
0.058
0.059
0.060
0.060
0.060
0.061
0.060
0.061
0.061
0.061
0.061
0.061
LDGT
<6001 Ibs.
0.054
0.054
0.054
0.053
0.053
0.054
0.054
0.055
0.056
0.056
0.057
0.058
0.059
0.060
0.061
0.061
0.062
0.062
0.063
0.062
0.063
0.062
0.063
0.063
0.063
0.063
0.064
LDGT
>6000 Ibs.
0.066
0.079
0.094
0.109
0.127
0.145
0.164
0.183
0.199
0.213
0.228
0.240
0.252
0.262
0.272
0.280
0.288
0.295
0.300
0.305
0.310
0.313
0.316
0.322
0.327
0.329
0.328
LDDT
0.053
0.127
0.199
0.269
0.334
0.390
0.440
0.482
0.517
0.547
0.570
0.588
0.604
0.618
0.629
0.639
0.646
0.651
0.656
0.660
0.664
0.666
0.668
0.672
0.675
0.675
0.672
HDGV
0.110
0.100
0.090
0.082
0.071
0.060
0.055
0.050
0.045
0.042
0.039
0.038
0.037
0.035
0.034
0.033
0.032
0.030
0.026
0.023
0.021
0.018
0.016
0.013
0.011
0.010
0.009
LDGV
0.019
0.020
0.021
0.022
0.024
0.027
0.029
0.031
0.033
0.035
0.037
0.039
0.040
0.042
0.043
0.044
0.044
0.045
0.046
0.046
0.046
0.047
0.047
0.047
0.047
0.047
0.047
LDGT
<6001 Ibs.
0.022
0.023
0.025
0.028
0.030
0.033
0.036
0.039
0.042
0.044
0.046
0.048
0.050
0.051
0.052
0.053
0.054
0.054
0.054
0.055
0.055
0.056
0.055
0.056
0.056
0.057
0.057
LDGT
>6000 Ibs.
0.024
0.034
0.046
0.059
0.073
0.089
0.105
0.121
0.134
0.148
0.161
0.172
0.182
0.191
0.200
0.207
0.214
0.219
0.224
0.229
0.233
0.237
0.240
0.245
0.250
0.251
0.251
LDDT
0.055
0.133
0.208
0.281
0.348
0.406
0.458
0.502
0.538
0.569
0.593
0.612
0.628
0.642
0.654
0.664
0.671
0.677
0.682
0.686
0.690
0.693
0.695
0.699
0.702
0.703
0.699
HDGV
0.040
0.038
0.036
0.034
0.030
0.027
0.025
0.023
0.021
0.020
0.020
0.020
0.019
0.020
0.019
0.019
0.019
0.018
0.016
0.014
0.013
0.012
0.011
0.010
0.008
0.008
0.007
MOBILES Information Sheet #8
April 2000
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Table 3
Difference in Hydrocarbon Emissions (grams per mile) Due to Tier 2/Sulfur Program
with Final I/M Programs
Conventional Gasoline Reformulated Gasoline
Calendar
Year
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
LDGV
0.042
0.042
0.043
0.044
0.045
0.046
0.047
0.049
0.050
0.051
0.052
0.054
0.055
0.056
0.058
0.059
0.059
0.060
0.060
0.060
0.061
0.060
0.061
0.061
0.061
0.061
0.061
LDGT
<6001 Ibs.
0.053
0.053
0.053
0.053
0.053
0.053
0.054
0.055
0.056
0.056
0.057
0.058
0.058
0.060
0.060
0.061
0.062
0.062
0.063
0.062
0.063
0.062
0.063
0.063
0.063
0.063
0.064
LDGT
>6000 Ibs.
0.064
0.077
0.092
0.108
0.125
0.145
0.164
0.181
0.199
0.214
0.227
0.240
0.252
0.262
0.271
0.280
0.288
0.295
0.300
0.305
0.310
0.313
0.316
0.322
0.327
0.329
0.328
LDDT
0.053
0.127
0.199
0.269
0.334
0.390
0.440
0.482
0.517
0.547
0.570
0.588
0.604
0.618
0.629
0.639
0.646
0.651
0.656
0.660
0.664
0.666
0.668
0.672
0.675
0.675
0.672
HDGV
0.110
0.100
0.090
0.082
0.071
0.060
0.055
0.050
0.045
0.042
0.039
0.038
0.037
0.035
0.034
0.033
0.032
0.030
0.026
0.023
0.021
0.018
0.016
0.013
0.011
0.010
0.009
LDGV
0.018
0.018
0.020
0.022
0.024
0.026
0.029
0.030
0.033
0.035
0.036
0.039
0.040
0.042
0.043
0.044
0.044
0.045
0.046
0.046
0.046
0.047
0.047
0.047
0.047
0.047
0.047
LDGT
<6001 Ibs.
0.021
0.023
0.024
0.027
0.030
0.033
0.035
0.038
0.041
0.044
0.046
0.048
0.050
0.051
0.052
0.053
0.054
0.054
0.054
0.055
0.055
0.056
0.055
0.056
0.056
0.057
0.057
LDGT
>6000 Ibs.
0.023
0.033
0.044
0.058
0.073
0.089
0.105
0.120
0.135
0.147
0.161
0.172
0.181
0.190
0.199
0.207
0.214
0.219
0.224
0.229
0.233
0.237
0.240
0.245
0.250
0.251
0.251
LDDT
0.055
0.133
0.208
0.281
0.348
0.406
0.458
0.502
0.538
0.569
0.593
0.612
0.628
0.642
0.654
0.664
0.671
0.677
0.682
0.686
0.690
0.693
0.695
0.699
0.702
0.703
0.699
HDGV
0.040
0.038
0.036
0.034
0.030
0.027
0.025
0.023
0.021
0.020
0.020
0.020
0.019
0.020
0.019
0.019
0.019
0.018
0.016
0.014
0.013
0.012
0.011
0.010
0.008
0.008
0.007
MOBILES Information Sheet #8
April 2000
-------
Table 4
Difference in Oxides of Nitrogen Emissions (grams per mile) Due to Tier 2/Sulfur Program
with No I/M Programs
Conventional Gasoline
Reformulated Gasoline
Calendar
Year
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
LDGV
0.215
0.241
0.270
0.303
0.338
0.371
0.405
0.437
0.466
0.490
0.510
0.526
0.540
0.551
0.560
0.567
0.572
0.576
0.580
0.582
0.586
0.588
0.588
0.588
0.589
0.589
0.586
LDGT
<6001 Ibs.
0.190
0.220
0.252
0.290
0.330
0.371
0.409
0.445
0.476
0.504
0.528
0.548
0.564
0.577
0.586
0.593
0.599
0.603
0.607
0.609
0.613
0.616
0.617
0.619
0.620
0.620
0.618
LDGT
>6000 Ibs.
0.170
0.227
0.295
0.366
0.439
0.512
0.581
0.645
0.702
0.753
0.800
0.841
0.878
0.910
0.939
0.965
0.986
1.006
1.024
1.039
1.052
1.064
1.075
1.092
1.109
1.116
1.113
LDDT
0.093
0.220
0.342
0.456
0.554
0.638
0.709
0.767
0.813
0.850
0.879
0.903
0.920
0.932
0.940
0.946
0.949
0.952
0.952
0.952
0.952
0.952
0.952
0.952
0.952
0.953
0.942
HDGV
0.491
0.468
0.448
0.431
0.415
0.401
0.389
0.380
0.373
0.363
0.355
0.350
0.346
0.341
0.339
0.335
0.333
0.330
0.328
0.326
0.325
0.324
0.323
0.321
0.319
0.319
0.319
LDGV
0.116
0.133
0.155
0.178
0.204
0.229
0.254
0.278
0.299
0.318
0.334
0.348
0.358
0.368
0.375
0.381
0.385
0.389
0.391
0.393
0.395
0.398
0.398
0.399
0.398
0.399
0.398
LDGT
<6001 Ibs.
0.108
0.133
0.161
0.195
0.232
0.268
0.303
0.335
0.364
0.390
0.412
0.430
0.445
0.457
0.465
0.473
0.478
0.482
0.485
0.487
0.490
0.493
0.494
0.495
0.496
0.497
0.495
LDGT
>6000 Ibs.
0.094
0.151
0.218
0.288
0.360
0.431
0.499
0.561
0.618
0.668
0.714
0.755
0.791
0.822
0.850
0.876
0.897
0.916
0.933
0.949
0.961
0.973
0.983
1.001
1.018
1.024
1.021
LDDT
0.094
0.223
0.347
0.460
0.559
0.644
0.716
0.774
0.821
0.859
0.889
0.912
0.930
0.943
0.951
0.957
0.960
0.963
0.963
0.963
0.964
0.963
0.964
0.964
0.964
0.965
0.954
HDGV
0.207
0.204
0.203
0.202
0.200
0.200
0.199
0.199
0.199
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.198
0.198
0.198
0.198
0.198
MOBILES Information Sheet #8
April 2000
-------
Table 5
Difference in Oxides of Nitrogen Emissions (grams per mile) Due to Tier 2/Sulfur Program
with Phase In I/M Programs
Calendar
Year LDGV
2004 0.204
2005 0.228
2006 0.255
2007 0.283
2008 0.313
2009 0.341
2010 0.368
2011 0.392
2012 0.415
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
0.434
0.450
0.462
0.473
0.481
0.488
0.493
0.497
0.500
0.503
0.505
0.507
0.509
0.508
0.509
0.509
0.509
0.507
Conventional Gasoline
LDGT LDGT
<60011bs. >60001bs. LDDT
0.184 0.162 0.095
0.210 0.218 0.229
0.239 0.283 0.361
0.273 0.352 0.486
0.309 0.420 0.599
0.343 0.490 0.699
0.377 0.556 0.785
0.408 0.617 0.857
0.435 0.674 0.916
0.460
0.480
0.498
0.512
0.523
0.532
0.539
0.543
0.547
0.550
0.552
0.555
0.558
0.558
0.559
0.560
0.561
0.558
0.726 0.965
0.772
0.815
0.853
0.887
0.917
0.942
0.965
0.985
1.003
1.018
1.031
1.041
1.052
1.069
1.086
1.092
1.088
.005
.036
.060
.079
.093
.104
.111
.118
.121
.124
.127
.128
.130
.132
.134
.135
.125
HDGV
0.491
0.468
0.448
0.431
0.415
0.401
0.389
0.380
0.373
0.363
0.355
0.350
0.346
0.341
0.339
0.335
0.333
0.330
0.328
0.326
0.325
0.324
0.323
0.321
0.319
0.319
0.319
LDGV
0.127
0.143
0.162
0.183
0.204
0.224
0.242
0.261
0.277
0.291
0.303
0.313
0.322
0.329
0.335
0.339
0.342
0.344
0.347
0.349
0.351
0.351
0.351
0.351
0.352
0.352
0.351
Reformulated Gasoline
LDGT LDGT
<60011bs. >60001bs. LDDT
0.106 0.090 0.097
0.129 0.144 0.233
0.154 0.209 0.366
0.185 0.275 0.492
0.219 0.344 0.605
0.252 0.411 0.705
0.284 0.475 0.791
0.314 0.535 0.863
0.340 0.589 0.922
0.364
0.385
0.402
0.417
0.428
0.436
0.442
0.448
0.451
0.454
0.457
0.459
0.461
0.461
0.462
0.464
0.465
0.462
0.640
0.686
0.726
0.764
0.796
0.824
0.850
0.872
0.892
0.908
0.923
0.936
0.947
0.957
0.974
0.991
0.997
0.994
0.970
1.009
1.040
1.063
1.082
1.096
1.106
1.114
1.120
1.124
1.127
1.129
1.131
1.133
1.134
1.136
1.138
1.127
HDGV
0.207
0.204
0.203
0.202
0.200
0.200
0.199
0.199
0.199
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.198
0.198
0.198
0.198
0.198
MOBILES Information Sheet #8
10
April 2000
-------
Table 6
Difference in Oxides of Nitrogen Emissions (grams per mile) Due to Tier 2/Sulfur Program
with Final I/M Programs
Conventional Gasoline
Reformulated Gasoline
Calendar
Year
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
LDGV
0.178
0.205
0.233
0.264
0.294
0.324
0.353
0.380
0.406
0.427
0.444
0.458
0.470
0.478
0.486
0.492
0.496
0.499
0.502
0.504
0.507
0.509
0.508
0.509
0.509
0.509
0.507
LDGT
<6001
Ibs.
0.182
0.208
0.238
0.272
0.308
0.343
0.376
0.406
0.434
0.459
0.480
0.497
0.512
0.523
0.531
0.538
0.543
0.547
0.550
0.552
0.555
0.558
0.558
0.559
0.560
0.561
0.558
LDGT
>6000
Ibs.
0.158
0.215
0.280
0.349
0.417
0.487
0.554
0.616
0.673
0.724
0.772
0.814
0.852
0.886
0.915
0.942
0.965
0.985
1.003
1.018
1.031
1.041
1.052
1.069
1.086
1.092
1.088
LDDT
0.095
0.229
0.361
0.486
0.599
0.699
0.785
0.857
0.916
0.965
1.005
1.036
1.060
1.079
1.093
1.104
1.111
1.118
1.121
1.124
1.127
1.128
1.130
1.132
1.134
1.135
1.125
HDGV
0.491
0.468
0.448
0.431
0.415
0.401
0.389
0.380
0.373
0.363
0.355
0.350
0.346
0.341
0.339
0.335
0.333
0.330
0.328
0.326
0.325
0.324
0.323
0.321
0.319
0.319
0.319
LDGV
0.088
0.106
0.126
0.149
0.172
0.195
0.218
0.240
0.261
0.278
0.293
0.306
0.317
0.325
0.332
0.336
0.341
0.344
0.345
0.347
0.349
0.351
0.351
0.351
0.352
0.352
0.351
LDGT
<6001
Ibs.
0.093
0.118
0.144
0.176
0.211
0.246
0.278
0.310
0.337
0.362
0.384
0.402
0.416
0.427
0.436
0.442
0.447
0.451
0.453
0.455
0.458
0.461
0.461
0.462
0.464
0.465
0.462
LDGT
>6000
Ibs.
0.089
0.144
0.208
0.274
0.343
0.411
0.475
0.535
0.590
0.640
0.686
0.726
0.764
0.796
0.825
0.850
0.872
0.892
0.908
0.923
0.936
0.947
0.957
0.974
0.991
0.997
0.994
LDDT
0.097
0.233
0.366
0.492
0.605
0.705
0.791
0.863
0.922
0.970
1.009
1.040
1.063
1.082
1.096
1.106
1.114
1.120
1.124
1.127
1.129
1.131
1.133
1.134
1.136
1.138
1.127
HDGV
0.207
0.204
0.203
0.202
0.200
0.200
0.199
0.199
0.199
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.197
0.198
0.198
0.198
0.198
0.198
MOBILES Information Sheet #8
11
April 2000
-------
Table 7
Parameters Used in Modeling
Temperature: All results are calculated at 72 and 96 degrees Fahrenheit, minimum and
maximum temperatures for VOC and NOx emissions and at 75 and 20
degrees Fahrenheit for CO emissions.
Fuel: "Conventional" gasoline is 9.0 Ibs. RVP with industry average 339 ppm
sulfur content. Reformulated Gasoline (RFG) is the federal final rule
program for Region 2 areas as defined for MOBILES in AP-42. Tier 2 fuel
sulfur control is assumed beginning in the 2004 calendar year.
Altitude: All results are for low altitude areas.
Month: All HC and NOx results are calculated for July 1st and all CO results are
calculated for January 1st of the calendar year.
Speed: All results are calculated for an areawide average trip speed of 24.6 miles per
hour.
Fleet: Fleet descriptors (registration distributions, mileage accumulations, etc.) are
national averages as proposed for MOBILE6.
I/M: Phase in Inspection and Maintenance (I/M) includes:
January 1986 start year, 20% stringency, 1968 and newer model year
coverage, 10% waivers, 85% compliance, test only, biennial
frequency, covering LDGV, LDGT1 and LDGT2, EVI240 test
procedure with 1.2/30./3.0 gram per mile HC/CO/NOx cutpoints for
1981 and newer model year vehicles. 1996 and newer model years
include both an evaporative pressure check and a purge system check
with 96% compliance. Tier 1 vehicles include an onboard diagnostic
(OBD) systems check.
Final I/M includes:
January 1986 start year, 20% stringency, 1968 and newer model year
coverage, 3% waivers, 96% compliance, test only, biennial
frequency, covering LDGV, LDGT1 and LDGT2, EVI240 test
procedure with 0.8/15./2.0 gram per mile HC/CO/NOx cutpoints for
1981 and newer model year vehicles. 1996 and newer model years
include both an evaporative pressure check and a purge system check
with 96% compliance. Tier 1 vehicles include an OBD check.
Op. Mode Default (20.6/27.3/20.6) operating modes were used.
MOBILES Information Sheet #8
12
April 2000
------- |