EPA-AA-TEB-89-01
USER'S GUIDE
to
MOBILE4
(MOBILE SOURCE EMISSION FACTOR MODEL)
FEBRUARY 1989
U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF AIR AND RADIATION
OFFICE OF MOBILE SOURCES
EMISSION CONTROL TECHNOLOGY DIVISION
TEST AND EVALUATION BRANCH
2565 PLYMOUTH ROAD
ANN ARBOR, MICHIGAN 48105
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DISCLAIMER
EPA will not be responsible for the accuracy of MOBILE4 tapes
that were received from sources other than EPA in Ann Arbor or
NTIS, or for the accuracy of any draft MOBILE4 tapes that may have
been released prior to release of the final MOBILE4 tapes.
Further, EPA will not be responsible for the accuracy of MOBILE4
when modified by the user without consultation with EPA.
Mention of specific products, product or corporate names, or
trademarks in no way constitutes endorsement of same by the U.S.
Government or by the Environmental Protection Agency.
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ABSTRACT
This document is the USER'S GUIDE to MOBILE4. MOBILE4 is a
computer program that calculates emission factors for hydrocarbons
(HC), carbon monoxide (CO), and oxides of nitrogen (NOx) from
gasoline-fueled and diesel highway motor vehicles. The program
uses the calculation procedures and emission factors presented in
Compilation of Air Pollutant Emission Factors: Highway Mobile
Sources (AP-42 Fourth Edition, September 1985). MOBILE4
calculates emission factors for eight individual vehicle types in
two regions of the country. MOBILE4 emission estimates depend on
various conditions such as ambient temperature, speed, and mileage
accrual rates. MOBILE4 will estimate emission factors for any
calendar year between I960 and 2020, inclusive. The 20 most
recent model years are considered to be in operation in each
calendar year. MOBILE4 supercedes MOBILES. Compared to MOBILES,
MOBILE4 incorporates several new options, calculating
methodologies, emission factor estimates, emission control
regulations, and internal program designs.
A revised supplement to the AP-42 document referenced above
will be prepared using MOBILE4 later in 1989. When this updated
supplement becomes available, it will be distributed to EPA
Regional Offices and will be available through the National
Technical Information Service. Section 2.5 of this User's Guide
contains information on ordering documents from NTIS.
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Requests for copies of the MOBILE4 program and for additional
copies of this User's Guide should be directed to the following:
The National Technical Information Service (NTIS)
U. S. Department of Commerce
Springfield, Virginia 22161
Telephone: (703) 557-4650
Questions concerning MOBILE4 or this User's Guide should be
directed to the following:
U. S. EPA Motor Vehicle Emission Laboratory
Office of Mobile Sources
Emission Control Technology Division
Test and Evaluation Branch
2565 Plymouth Road
Ann Arbor, MI 48105
Attn: MOBILE4
Telephone: (313) 668-4462 (FTS 374-8462)
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TABLE OF CONTENTS
Page
CHAPTER 1: GENERAL DESCRIPTION OF MOB ILE4
1.0 INTRODUCTION 1-1
1.1 PRIMARY TECHNICAL DIFFERENCES FROM MOBILE3 1-2
1.1.1 Addition of Running Loss Emissions
1.1.2 Addition of Refueling Emissions
1.1.3 Volatility Emission Impact and Volatility Control
1.1.4 Temperature Calculations
1.1.5 Deterioration Rates for MY 1981+ LDGV Emissions
1.1.6 Basic Emission Rates for HDVs
1.1.7 Component HC Emission Factors
1.1.8 Idle Emission Rates
1.1.9 Exhaust Emission Temperature Corrections
1.1.10 Trips per Day and Miles per Day
1.1.11 Revisions to Evaporative Emission Factor Calculations
1.1.12 Tampering Effects on Emissions
1.1.13 Anti-Tampering Programs
1.1.14 Inspection/Maintenance Programs
1.3 LIST OF ABBREVIATIONS USED IN THIS DOCUMENT 1-16
CHAPTER 2: MOBILE4 INPUTS
2.0 INTRODUCTION 2-1
2.1 CONTROL SECTION 2-3
2.1.1 PROMPT 2.1.11 ATPFLG
2.1.2 IOUNEW 2.1.12 RLFLAG
2.1.3 PROJID 2.1.13 LOCFLG
2.1.4 TAMFLG 2.1.14 TEMFLG
2.1.5 SPDFLG 2.1.15 OUTFMT
2.1.6 VMFLAG 2.1.16 PRTFLG
2.1.7 MYMRFG 2.1.17 IDLFLG
2.1.8 NEWFLG 2.1.18 NMHFLG
2.1.9 IMFLAG 2.1.19 HCFLAG
2.1.10 ALHFLG 2.1.20 Inter-Flag Dependencies
2.2 ONE-TIME DATA SECTION 2-15
2.2.1 Tampering Rates
2.2.2 Vehicle Miles Travelled Mix by vehicle type
2.2.3 Annual Mileage Accumulation Rates and/or
Registration Distributions by vehicle type
2.2.4 Basic Emission Rates
2.2.5 Inspection and Maintenance Programs
2.2.6 Anti-Tampering Programs
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TABLE OF CONTENTS (continued)
Page
2.2 ONE-TIME DATA SECTION (continued)
2.2.7 Refueling Emissions
2.2.8 Local Area Parameter Record
2.2.9 Scenario Name
2.2.10 ASTM Volatility Class
2.2.11 Minimum and Maximum Ambient Temperatures
2.2.12 Base RVP
2.2.13 In-Use RVP and In-Use Start Year
2.3 SCENARIO SECTION 2-34
2.3.1 Region
2.3.2 Calendar Year
2.3.3 Speed
2.3.4 Ambient Temperature
2.3.5 Operating Modes
2.3.6 Local Area Parameter Record
2.3.7 Vehicle Miles Travelled by vehicle type
2.3.8 Additional Correction Factors for Light-Duty
Gasoline-Fueled Vehicle Types
2.4 SUMMARY OF MOBILE4 INPUT SEQUENCE 2-46
2.5 OBTAINING REFERENCED DOCUMENTS 2-46
APPENDIX 2A: Inspection and Maintenance and Anti-Tampering
Program Terminology Definitions 2-65
APPENDIX 2B: RVP and ASTM Class Determination Guidance . . . 2-75
APPENDIX 2C: Input Temperature Determination Guidance . * . . . 2-83
CHAPTER 3: MOBILE4 OUTPUTS
3.0 INTRODUCTION 3-1
3.1 PROMPTING MESSAGES 3-1
3.1.1 Control Section Prompts 3-2
3.1.1.1 Title Record Prompt
3.1.1.2 Remaining Flag Prompts
3.1.2 One-time Data Section Prompts 3-5
3.1.2.1 Tampering Rate Prompts
3.1.2.2 VMT Mix Record Prompt
3.1.2.3 Annual Mileage Accumulation Rates and/or
Registration Distributions by Age Prompts
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TABLE OF CONTENTS (continued)
Page
3.1 PROMPTING MESSAGES (continued)
3.1.2 One-time Data Section Prompts (continued)
3.1.2.4 Alternate BER Prompts
3.1.2.5 I/M Program Parameter Record Prompt
3.1.2.6 ATP Parameter Record Prompt
3.1.2.7 VRS Descriptive Record Prompt
3.1.2.8 LAP Record Prompt
3.1.3 Scenario Section Data Prompts 3-7
3.1.3.1 Scenario Descriptive Record Prompt
3.1.3.2 LAP Record Prompt
3.1.3.3 VMT Mix Record Prompt
3.1.3.4 Additional Light-Duty
Correction Factor Record Prompt
3.2 DIAGNOSTIC MESSAGES 3-10
3.2.1 Introduction
3.2.2 Explanation of Messages, Listed by Number
3.3 FORMATTED REPORT OUTPUT 3-28
3.3.1 221-Column Numeric Output
3.3.2 140-Column Numeric Output
3.3.3 112-Column Descriptive Output
3.3.4 80-Column Descriptive Output
CHAPTER 4: MOBILE4 IMPLEMENTATION
4.0 INTRODUCTION 4-1
4.1 MOBILE4 TAPE 4-1
4.2 PROGRAM STORAGE REQUIREMENTS 4-2
4.3 PROGRAM EXECUTION TIME 4-2
4.4 DEVIATIONS FROM ANSI FORTRAN STANDARD X3.9-1978 4-3
4.5 TYPICAL JOB STRUCTURE 4-3
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TABLE OF CONTENTS (continued)
Paqe
4.6 INSTALLATION, COMPILING, AND EXECUTION
OF MOBILE4 ON PERSONAL COMPUTER SYSTEMS 4-5
4.6.1 Introduction
4.6.2 Installation, Compiling, and Execution
of MOBILE4 on an Apple Macintosh PC
4.6.3 Installation, Compiling, and Execution
of MOBILE4 on an IBM PC-AT (or clone)
4.7 PROGRAM UPDATE INFORMATION 4-8
CHAPTER 5: MOBILE4 EXAMPLES
5.0 INTRODUCTION 5-1
5.1 EXAMPLES 5-1
5.1.1 Basic Run Example 5-2
5.1.2 In-Use Volatility Control and
Onboard VRS Requirement Example 5-15
5.1.3 I/M and ATP Example 5-21
5.1.4 Replacement of MOBILE4 Data Example 5-27
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List of Tables
Table Title and Description Page
2.1-1 Flags Controlling Input to and Execution of MOBILE4 . 2-48
2.1-2 Flags Controlling Output of MOBILE4 2-52
2.2-1 Summary of Alternate BER Records 2-53
2.2-2 Summary of I/M Program Descriptive Input Record . . . 2-54
2.2-3 Summary of ATP Descriptive Record 2-56
2.2-4 Summary of Stage II and Onboard VRS
Descriptive Input Records 2-58
2.2-5 Summary of the Local Area Parameter (LAP) Record . . 2-59
2.3-1 Summary of the Scenario Record(s) 2-60
2.4-1 Summary of the MOBILE4 Input Record Sequence .... 2-64
2C.3-1 Suggested Local Climatological Data Stations for
Use in Determining Temperatures, for Selected
Ozone and Carbon Monoxide Non-Attainment Areas . . 2-86
3.3-1 Number and Content of Records per Scenario 3-39
4.1-1 MOBILE4 Tape Characteristics 4-2
4.3-1 Comparison of MOBILE4 and MOBILES Execution Times . . 4-3
5.1-1 Summary Description of MOBILE4 Examples 5-1
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Chapter 1
GENERAL DESCRIPTION OF MOBILE4
1 .0 INTRODUCTION
MOBILE4 is an. integrated set of FORTRAN routines for use in
the analysis of the air pollution impact of gasoline-fueled and
diesel highway mobile sources. The system has been designed to
provide the user with a flexible analytical tool which can be
applied in a wide variety of air quality planning functions.
MOBILE4 is an update of its predecessors MOBILE 1. 2, and 3.
MOBILE4 calculates emission factors for gasoline-fueled
light-duty vehicles (LDVs), light-duty trucks (LDTs), heavy-duty
vehicles (HDVs), and motorcycles, and for diesel LDVs, LDTs, and
HDVs. EPA's emission factor data base does not contain adequate
data to model emission factors for vehicles using alternative
fuels or fuel blends (such as oxygenated fuels) in the same way
that gas and diesel emission factors are modeled. Modeling
emission factors for vehicles operated on oxygenated fuels depends
on a number of other variables, such as the oxygen content of the
fuel, that MOBILE4 is not coded to handle. EPA has developed
procedures for modeling emission factors for vehicles operating on
oxygenated and alternative fuels, which are detailed in the report
"Guidance on Estimating Motor Vehicle Emission Reductions From the
Use of Alternative Fuels and Fuel Blends." See section 2.5 for
information on obtaining this report.
This chapter explains the primary technical differences
between MOBILE4 and MOBILE3. Instructions on how to use the
program are contained in Chapter 2 (MOBILE4 Inputs), Chapter 3
(MOBILE4 Outputs), Chapter 4 (MOBILE4 Implementation), and
Chapter 5 (MOBILE4 Examples). The source code listing of the
MOBILE4 program has been printed under separate cover, rather than
being included as an appendix to the User' s Guide as was done with
earlier versions of the model. Of course, the user possessing a
copy of MOBILE4 on magnetic tape can generate their own listing of
the source code.
This User's Guide is intended to be a self-contained
document, such that earlier versions of the User's Guide are no
longer necessary references for operation of MOBILE4. Although
not required for the use of MOBILE4, some users may still wish to
obtain the User's Guide to MOBILE2 and User's Guide to MOBILES.
Information on obtaining these documents appears in section 2.5.
1.1 PRIMARY TECHNICAL DIFFERENCES FROM MOBILES
In addition to updates that have been made to the emission
factor data base as a result of the considerable amount of new
test data collected since the development of MOBILES, there have
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been a number of changes to the methodology used to calculate some
of the emission factors and correction factors. This section does
not attempt to detail every case where the data base has been
updated. The sections below describe (1) those features that are
entirely new to MOBILE4, and thus have no direct corollary in
earlier versions of the model, and (2) those features that have
been significantly revised since MOBILES. The "new" features are
described in sections l.l.l thorough 1.1.4, and the significantly
revised features are described in sections 1.1.5 through 1.1.13.
1.1.1 Addition of Running Loss Emissions
Perhaps the most significant change to MOBILE4, at least in
terms of the output emission factors, is the addition of running
loss hydrocarbon (HC) emission factors. Running loss emissions
are defined as evaporative emissions occuring while the vehicle is
in operation, that is, while it is being driven. The occurrence
of running loss emissions appears to be at least in part the
result of insufficient evaporative canister purging during vehicle
operation; when the canister reaches saturation and evaporative
emissions continue to be generated as a result of fuel tank
temperature increases, these emissions are released from the
vehicle into the atmosphere. Vehicle fuel system leaks, and
possibly other sources, may also contribute to the generation of
running loss emissions. These emissions were assumed to be zero
in all previous versions of the mobile source emission factor
model.
Test programs conducted by EPA beginning in 1988 have shown
that running loss emissions are not zero under many conditions,
particularly at the lower speeds representative of urban driving.
Running losses have been determined to be a function of several
variables, most importantly temperature, fuel volatility, and
average speed of operation. These emissions also depend on
vehicle type, vehicle age, and the evaporative control system.
Since there are as yet insufficient data to characterize
running loss emissions in the level of detail used for the
modeling of exhaust and "standard" evaporative emissions (i.e.,
hot soak and diurnal evaporative emissions), a number of
assumptions have been incorporated into MOBILE4 to allow the
calculation of running loss emission factors. These emissions
will be calculated whenever HC emission factors are requested, and
are included in the total HC emission factors. If listing of the
individual components of the HC emission factor are requested,
these emissions are listed separately under the heading "Runing L"
(see section 3.3), along with the exhaust, "standard" evaporative,
and refueling loss (see sections 1.1.2 and 2.2.7) HC emissions.
EPA's data have shown that running loss emissions are a
non-linear function of temperature, fuel volatility (as measured
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by RVP), and average speed. Running loss emissions are higher at
higher temperatures and higher volatilities (as are other
evaporative emissions), and are higher at lower average speeds
(reflecting the lesser canister purging that occurs at low
speeds). The data on which the running loss emission factors used
in MOBILE4 are based on tests of light-duty gasoline-fueled
vehicles and trucks tested over three different driving cycles
having different average speeds, at several different
temperatures, and using fuels of varying volatility.
Results from running loss testing over these three driving
cycles, which included the FTP, showed that running loss emissions
were very low at highway speeds, regardless of temperature or fuel
volatility. This reflects the fact that at higher speeds, the
purging of the evaporative control canister generally is more than
adequate to handle evaporative emissions generated while driving.
Running loss emissions are higher at FTP speeds, which are
considered representative of much urban driving. The highest
running losses as a function of speed occurred over the lowest
speed cycle used, corresponding to the conditions in which the
least degree of canister purging occurs.
As with other evaporative emissions, running losses increase
rapidly with increasing fuel volatility and temperature. In
MOBILE4, ceilings are placed on the increase in running losses
with increasing temperature and volatility to avoid unreasonable
extrapolation based on limited data. Maximum running losses are
assumed to occur at 105°F (41°C), with temperatures over that
resulting in no further increase in running losses. Maximum
running losses as a function of fuel volatility are assumed to
occur at 11.7 psi RVP, which is the highest volatility fuel for
which EPA has collected data.
In MOBILE4, running losses are calculated as a function of
temperature and fuel volatility. The available data were
insufficient for the direct modeling of running losses as a
function of vehicle speed in MOBILE4, thus the running loss
emission factors are a weighted composite of the results
determined for the three average speeds tested, with appropriate
weighting for fractions of vehicle travel in each of three bands
of average speed. These weighting factors were determined on the
basis of urban travel characteristics, and are not appropriate for
application to rural areas. Separate running loss emission
factors are calculated for each gasoline-fueled vehicle type
except motorcycles (which represent a very small fraction of VMT).
As EPA continues to develop more running loss test data, the
modeling of running loss emissions may be made more specifically
speed-dependent in the future. However, the estimated emission
factors in MOBILE4 are considered reasonably accurate for urban
areas, and are certainly much more closely representative of
actual in-use running loss emissions than were the previous
assumptions (i.e., that there were no running loss emissions).
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1.1.2 Addition of Refueling Emissions
Another type of evaporative HC emissions that were not
included in previous versions of the model are refueling
emissions. These emissions, also termed "Stage II" emissions, are
generated when vehicles are refueled. (Stage I emissions are HC
vapor emissions displaced to the atmosphere from underground
service station gasoline storage tanks when these tanks are
refilled, and are already controlled in most areas.) Stage II
refueling emissions consist primarily of displacement losses,
which occur during vehicle refueling when the gasoline vapor
filling the vehicle fuel tank vapor space (that space remaining
above whatever liquid fuel remains in the tank) are displaced by
incoming fuel and released to the atmosphere, and to a lesser
extent of spillage losses (whatever fuel is spilled, or dripped
from the dispensing nozzle, during vehicle refueling, which
completely evaporates). EPA estimates that vehicle refueling
emissions account for approximately two percent of the overall
inventory of HC emissions in urban areas.
In previous versions of the mobile source emission factor
model, refueling emissions were not accounted for. Stationary
source emission inventory "Stage II" emissions, based on total
gasoline throughput and an associated emission factor, were
previously the only method available for modeling these
emissions. MOBILE4 has incorporated refueling emission data
combined with fleet fuel economy data to yield refueling emission
factors in grams per mile for LDGVs, LDGTs, and HDGVs. By
modeling refueling emissions as a mobile source, the relative
contribution of these emissions to overall mobile source HC
emissions is made clearer, and the air quality planner can model
the impact of onboard or Stage II vapor recovery system
requirements on these emissions. See section 2.2.7 for additional
information.
Vehicle refueling emissions are calculated and included in
the total HC emission factors, unless MOBILE4 is specifically
instructed not to do so through the use of the RLFLAG control flag
(see section 2.1.12). If the user requests that the components of
the total HC emission factor be listed in the output, these
emissions are identified by the label "Refuel L" (see section 3.3),
and are listed along with exhaust, evaporative, and running loss
HC emissions.
1.1.3 Volatility Emissions Impact and Volatility Control
EPA's certification procedures for new motor vehicles, and
much of the emission factor data base used for MOBILE4, are based
on testing using gasoline with volatility of 9.0 psi Reid vapor
pressure (RVP). This was representative of the gasoline marketed
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in much of the country in the early to mid 1970s, when these test
procedures were developed. In recent years, the volatility of
commercially marketed fuel has increased substantially. Emission
factor program testing has demonstrated that increased fuel
volatility has an impact on all components of vehicle HC
emissions. This impact is greatest on evaporative emissions,
including running loss emissions, but also is seen in the exhaust
emission results.
MOBILE1 and MOBILE2 assumed 9.0 psi RVP fuel in calculating
emission factors. MOBILES accounted for the increase in
commercial fuel volatility that was already being seen in the
early 1980s by basing evaporative emission factor results on
commercial (11.5 psi RVP) fuel. (Exhaust emission factors were
still based on 9.0 psi RVP fuel.) MOBILE4 takes this several
steps further by modeling the impact of fuel volatility on exhaust
HC, CO, and NOx emissions, and on hot soak and diurnal
evaporative, refueling, and running loss HC emissions. In
addition, the user of MOBILE4 can model the effects of different
volatility in a future evaluation year, as would be seen if a
program to regulate in-use fuel volatility (whether on the
Federal, regional, or State level) were implemented. Only a
single change in fuel volatility can be modeled within a single
MOBILE4 run.
The effects of fuel volatility on exhaust emissions are
modeled dependent on temperature, with the impact of increased
volatility being greater at higher temperatures. For model year
(MY) 1970 and earlier LDGVs, no impact of volatility on exhaust
emissions is modeled. For MY 1971-79 HC and CO emissions from
LDGVs, the volatility impact on exhaust emissions is applied as a
correction factor calculated independent of the temperature
correction factor, but with the volatility correction factor being
a function of temperature. No volatility impact on MY 1971-79 NOx
emissions was statistically significant on the basis of available
data, thus none is included in MOBILE4. For MY 1980 and later
LDGVs, for all three pollutants, the volatility correction is
calculated in conjunction with the temperature correction factor
for temperatures at and above the standard FTP temperature of 75°F
(see section 1.1.9). The volatility corrections for LDGT and HDGV
exhaust emissions are based on the LDGV data and model year
mappings that take into account the evaporative emission control
technology in use.
The effects of temperature and fuel volatility on "standard"
evaporative emissions (hot soak and diurnal) are also modeled.
See section 1.1.11 for discussion of the changes made in the
calculation of evaporative emission factors. The effects of
volatility on refueling emissions are based on the ASTM volatility
class of the area being modeled, which approximates the actual
in-use RVP for a given area. Running loss emissions are a direct
function of the user-specified RVP for the evaluation year.
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The effects of fuel volatility on emissions, as noted above,
appear to vary with temperature, with larger emissions impacts
observed at higher temperatures. In MOBILE4, volatility has no
effect on exhaust emissions if the temperature used for correcting
exhaust emissions is at or below 40°F. Evaporative emissions (hot
soak, diurnal, running loss, and refueling) are not calculated at
all if the applicable temperatures are at or below 40°F (see
section l.l.ll). For temperatures above 40°F, fuel volatility
impacts all components of HC emissions, with the effects
increasing with increasing temperature.
The MOBILE4 user must now specify a base year RVP level in
the input. This value should be representative of the RVP of
gasoline marketed in the area being modeled in the base year of
the analysis (in most cases, this will the same as current in-use
average fuel RVP). The impacts of a fuel volatility control
regulation, such as that proposed by EPA in August 1987, can also
be modeled through the specification of the in-use fuel volatility
controlled level and the year in which the in-use control program
takes effect. The effects of volatility apply to all vehicles,
regardless of age, and thus do not depend on fleet turnover to
show an impact on the emission factors. Specification of an
in-use fuel volatility control program results in a one-time
"step" change in the emission factors, with all evaluation years
up to the last year before the in-use start year modeled using the
base RVP value, and all evaluation years beginning with the in-use
start year modeled using the in-use (controlled) RVP level. See
sections 2.2.12 and 2.2.13 for additional discussion.
1.1.4 Temperature Calculations
In MOBILES, the user specified an ambient temperature as part
of the required Scenario descriptive (or parameter) record. This
temperature was used in the calculation of temperature correction
factors (TCFs) for exhaust HC, CO, and NOx emissions. The
evaporative emission factors calculated by MOBILES were based on
standard FTP evaporative emission rates (including diurnal
temperature range of 60°-84°F and hot soak temperature of 82°F),
regardless of the input ambient temperature.
MOBILE4 uses a considerably more sophisticated approach to
correcting emission factors for temperature, with the result being
both more accuracy in the temperature corrections and more
consistency in the temperature corrections applied to various
components of overall emissions. This is accomplished by
requiring the user to input three temperature values: minimum
daily temperature, maximum daily temperature, and ambient
temperature. There is a new flag in the Control section of the
input (TEMFLG, see section 2.1.14), which partly determines how
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these three temperatures will be used in the correction of
emission factors for temperature effects.
If the value of TEMFLG is 1 (as is recommended for most SIP-
related modeling), then MOBILE4 uses the input minimum and maximum
daily temperatures to calculate up to nine other temperatures for
use in correcting various components of emissions (see
section l.l.ll). Although the user must still supply a value of
ambient temperature as part of the Scenario section data, this
value is not used if TEMFLG = 1. MOBILE4 allows the user-input
ambient temperature to be used in emission factor temperature
corrections, by setting TEMFLG = 2, although the use of this
option is recommended only in certain specific modeling situations
(see section 2.2.11.3).
There are up to six emission factors that are corrected for
temperature in MOBILE4 (exhaust HC, exhaust CO, exhaust NOx,
diurnal evaporative HC, hot soak evaporative HC, and running
loss HC), depending on the temperature(s) applicable to the
scenario being evaluated. If TEMFLG = 1, the temperatures used in
determining the corrections for the three exhaust emission
factors, and for the hot soak and running loss HC emission
factors, are determined by MOBILE4 on the basis of the input
minimum and maximum daily temperatures and the variation in
emissions with temperature over that temperature range. See
section 2.2.11.3 for additional discussion.
The diurnal portion of evaporative HC emissions is calculated
on the basis of the temperature rise (maximum minus minimum)
vehicles would experience on a day with the given minimum and
maximum temperatures. See section l.l.ll for additional
description of the changes in the calculation of hot soak and
diurnal evaporative emission factors in MOBILE4.
The use of the input minimum and maximum daily temperatures,
and the calculation of the appropriate temperatures for use in
correcting emission factors on the basis of those temperatures,
leads to temperature correction factors (TCFs) that more
accurately reflect average emissions over the course of a given
day characterized by the minimum and maximum temperatures
specified. In addition, the evaporative emissions are now
corrected for temperature, and thus are more consistent with the
exhaust emissions calculated for the same scenario.
If TEMFLG = 2, then the input ambient temperature is used as
the temperature for calculation of the exhaust TCFs for all three
pollutants, the hot soak TCF, and running loss emissions.
However, the input minimum and maximum temperatures are still used
in the calculation of the diurnal emission factors. For this
reason, all three temperatures must be specified in the input
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regardless of the value assigned to TEMFLG, and care should be
taken in making the relationship between the three input
temperature values realistic (e.g., the ambient must lie between
the minimum and the maximum, the maximum must be greater than or
equal to the minimum).
Additional information related to the use of temperature
input data in MOBILE4 and its use in correcting emissions for the
effects of temperature can be found in sections 2.1.14 (TEMFLG),
2.2.11 (Minimum and maximum daily temperatures), and 2.3.4
(Ambient temperature). Suggested guidance on the determination of
appropriate temperatures for use in SIP-related modeling for both
ozone (HC emissions) and CO appears in Appendix 2C to Chapter 2 of
this document.
1.1.5 Deterioration Rates for MY 1981+ LDGV Emissions
As in all previous updates of the emission factor model, the
basic emission rates have been revised to reflect additional
emission factor test program data. In MOBILE4, the additional
data collected and analyzed since the previous revision of the
model has resulted in a more significant change in the modeling of
1981 and later model year light-duty gasoline-fueled vehicle
emissions. For exhaust HC and CO emissions only, there are now
two separate deterioration rates applied to the emission factors.
All basic emission rates are modeled using a zero-mile level
(ZML), which is an expression of new vehicle emissions in g/mi.
Since vehicle emissions have been modeled as a linear function of
vehicle age (for properly maintained, non-tampered vehicles), the
ZML can also be interpreted as the y-intercept of a line defining
emissions as a function of accumulated mileage. The slope of this
line is termed the deterioration rate (DR), and expresses the
increase in emissions per 10,000 miles of accumulated mileage.
Thus, the units of the DR are (g/mi)/10K mi.
Emission factor data for 1981 and later LDGVs show that
emissions from these vehicles deteriorate at a more rapid rate
(i.e., the line defining emissions as a function of accumulated
mileage has a steeper slope) after 50,000 accumulated miles than
before 50,000 miles. For this reason, MOBILE4 uses two
deterioration rates in the modeling of 1981+ LDGV exhaust
emissions: one applicable to accumulated mileage up to 50,000
miles, and a second, higher one applicable to accumulated mileage
after 50,000 miles. While there is some reason to believe that
similar behavior would be exhibited for late model light-duty
gasoline-fueled trucks (LDGTls and LDGT2s), based on the
similarities in the stringency of applicable emission standards
and emission control technology used, the emission factor data
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base does not yet reflect similar emissions deterioration behavior
for these vehicles with sufficient confidence for incorporation of
this effect in MOBILE4. Thus, the use of two deterioration rates
in MOBILE4 is limited to 1981 and later LDGVs.
The impact of this change on the user of MOBILE4 is
transparent, except when alternate basic emission rates are being
input to the model. If the user is implementing modifications to
the basic exhaust emission rates for 1981+ LDGVs (thorugh use of
the NEWFLG control flag; see section 2.1.8), then two
deterioration rates must be supplied. See section 2.2.4 for
further information.
1.1.6 Basic Emission Rates for HDVs
EPA regulates heavy-duty gasoline-fueled and diesel engines
(HDGEs and HDDEs) on the basis of mass emissions per unit work
performed, rather than per unit distance travelled, due to the
wide variety of in-use applications of such engines. The units
are grams per brake horsepower-hour (g/BHP-hr). MOBILES modeled
heavy-duty vehicle (HDV) emission factors using emission rates
expressed in grams per mile (g/mi), with the conversion of
g/BHP-hr to g/mi emission rates based on conversion factors
expressing the average amount of work performed by different
engines in order to travel given distances. In MOBILE4, updated
model-year-specific conversion factors are used to convert
modified basic emission rates in g/BHP-hr to g/mi rates
internally. This provides for compatibility of HDV emission
factors with those for other vehicle classes and for use in
inventory development.
In a similar fashion to the change described above for 1981
and later LDGV emissions, this change is transparent to the
MOBILE4 user, unless the user is supplying modifications to the
basic emission rate equations applicable to HDVs. Rather than
g/mi rates, the user must supply modifications to the HDV emission
rates in terms of g/BHP-hr for the ZML and (g/BHP-hr)/IOK mi for
the DR. See section 2.2.4 for additional information.
1.1.7 Component HC Emission Factors
With the addition of running loss (section 1.1.1) and
refueling loss (section 1.1.2) HC emissions to MOBILE4, the HC
total and component emission factors are now different than were
seen in MOBILES. The total HC emission factor includes running
losses, and also includes refueling losses unless they are
specifically excluded by the user through the RLFLAG control flag
(see section 2.1.12). When the user requests that the the
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component emission factors constituting the total HC emission
factor be printed in the output (through the use of the HCFLAG
control flag; see section 2.1.19), there will now be four
components, rather than the two shown by MOBILES. These
components are exhaust emissions (same as MOBILES), evaporative
(hot soak and diurnal) emissions including crankcase emissions
(same as MOBILES), refueling emissions (unless excluded through
use of RLFLAG), and running loss emissions. This also results in
considerably longer MOBILE4 formatted output reports, as described
in section 3.3.
1.1.8 Idle Emission Rates
The idle emission rates in MOBILE4 have been updated for the
first time since the release of MOBILE2 in 1981. There are four
differences in the idle emission factors for MOBILE4.
For HC and CO emissions, the idle emission rates are now
estimated as a function of stabilized FTP emission rates for the
following vehicle types and model year groups: 1977 and later
LDGVs, 1979 .and later LDGTs, and 1984 and later HDGVs. For
properly functioning vehicles, stabilized (hot) idle emission
rates are logically only slightly lower than very low speed
emissions in stabilized operating mode, since the demand placed on
the vehicle engine differs only slightly between idle operation
and very low speed operation.
This statement is literally true only if the comparison
between idle and low speed emissions is made in consistent units,
namely in grams pollutant per unit time. In MOBILE4, idle
emissions are calculated and expressed in the output in 'units of
grams per hour (g/hr). This is the second difference, in that
idle emissions in MOBILES were expressed in g/min. Thus, the
numerical values of the idle emission factors will look very large
relative to those of MOBILES. When converted to the same units,
the differences between MOBILES and MOBILE4 idle emission factors
generally are not large.
The other two differences relate to the inclusion in the idle
emission factors of the benefits of I/M programs and of offsets
for certain forms of tampering. The forms of tampering which are
considered to affect idle emissions are misfueling, catalyst
removal, and air system (air pump or pulse air) disconnection.
The idle I/M credits are the same in percentage terms as the
corresponding FTP cycle I/M credits.
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1.1.9 Exhaust Emission Temperature Corrections
The coefficients of the temperature correction factor
equations for exhaust HC, CO, and NOx emissions have been updated
on the basis of additional test data obtained since development of
MOBILES. For "high" temperatures (greater than the standard FTP
temperature of 75°F), as noted in section 1.1.3, the temperature
correction factor model now accounts for the effects of
temperature, fuel volatility, and interactions between the two
effects. This combined RVP and temperature correction factor
model is applied only for 1980 and later model year LDGVs and 1981
and later model year LDGTs, since these are the only vehicles for
which adequate test data with both varying temperature and fuel
volatility are available.
1.1.10 Trips per Day and Miles per Day
MOBILES assumed that all LDGVs and LDGTs travelled 31.1 miles
per day (MPD) took 3.05 trips per day (TPD) . The corresponding
values for HDGVs and motorcycles were 36.7 MPD/6.88 TPD and
8.30 MPD/1.35 TPD, respectively. These values were constant for
vehicles of all ages, based on average travel characteristics.
In MOBILE4, the values of TPD and MPD have been updated on
the basis of more recent information, and have been made a
function of vehicle age for LDGVs and LDGTs (for HDGVs and
motorcycles, due to insufficient data, constant TPD and updated
MPD values continue to be used in MOBILE4) . Thus, MPD is tied
directly to the annual mileage accumulation rate by age for LDGVs
and LDGTs (see section 2.2.3). TPD is a function of vehicle age
only. This clearly reflects the data more accurately, since all
available data indicate that newer vehicles are driven more often
(higher TPD) and for greater distances (higher MPD) than are older
vehicles.
Considering the analysis used to develop the functions
expressing TPD and MPD as functions of vehicle age, and the
importance of these values in the determination of evaporative
emission rates in g/mi terms (see section 1.1.11), this change led
to another change in MOBILE4 relative to MOBILE3. The old ICEVFG
flag has been deleted, and is replaced by the HCFLAG flag
(section 2.1.19). As part of this change, the MOBILE4 user is no
longer permitted to input TPD and MPD rates different from those
included in MOBILE4. (However, as noted above, MPD is a function
of the annual mileage accumulation rates by age. Since it is
possible for this information to be altered by the user having
adequate locality-specific data, the user indirectly is still
capable of incorporating locality-specific information in the MPD
calculations.)
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1.1.11 Revisions to Evaporative Emission Factor Calculations
Numerous significant revisions have been made to the
calculation of hot soak and diurnal evaporative HC emissions in
MOBILE4. These are briefly described below.
In MOBILES, evaporative emission rates by vehicle type, model
year group, and fuel delivery system did not vary on the basis of
temperature information input by the user, or on the basis of fuel
volatility. Thus, evaporative emission factors always reflected
the conditions of the FTP, with the diurnal emission rates based
on temperatures ranging from 60° to 84°F, the hot soak emission
rates based on 82°F, and both based on commercial (11.5 psi RVP)
fuel, regardless of the temperature specified by the user.
In the conversion of evaporative emission rates to g/mi
units, MOBILES used a constant average of 3.05 trips per day (TPD)
and 31.1 miles per day (MPD) for all LDGVs and LDGTs, with each
vehicle assumed to undergo one hot soak after every trip and one
complete diurnal per day:
3.05 * [Hot soak emissions (g/test)]
Evap HC (g/mi) = + [Diurnal emissions (g/test)1
31.1 miles
In MOBILE4, there are three major differences in the
calculation of evaporative emission rates. Both diurnal and hot
soak rates are now based on the user input minimum and maximum
daily temperatures, both are dependent on the user input fuel RVP,
and the fractions of vehicles assumed to experience hot soaks and
diurnal emission generation cycles are based on analysis of a
large amount of detailed trip information. Each of these changes
results in more accurate and realistic evaporative emission
factors, and each is discussed briefly below.
The temperature and volatility dependencies of hot soak
evaporative emissions are based on the results of emission factor
testing of vehicles at several different temperatures and using
fuels of differing volatilities. Correction factor equations were
developed through regression analysis, and the resulting
correction factors are applied to the standard FTP hot soak
emission rates. As discussed in section 1.1.4, the temperature
used for the correction of hot soak emission rates is based on the
minimum and maximum daily temperatures input by the user.
Diurnal emissions as a function of temperature and volatility
are developed through the use of the uncontrolled diurnal index
(UDI), which expresses diurnal emissions for a given temperature
range and fuel volatility as a multiple of standard FTP diurnal
emissions. The UDI model and its development are described in
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more detail in the regulatory support document for the Notice of
Proposed Rulemaking regarding in-use fuel volatility control.*
Adjustments are included to account for the effects of average
in-use fuel tank levels and the effects of in-use fuel weathering,
further improving the accuracy of the evaporative emission factors.
The last major change in the calculation of evaporative
emission rates concerns the assumptions made as to the number and
types of hot soak and diurnal emission cycles experienced by
vehicles. Diurnal emissions are generated when the vehicle is not
driven during a period characterized by rising ambient
temperatures, while hot soak emissions are generated at the
completion of every trip.
Standard FTP diurnal emission rates represent emissions
generated during a 24 F° temperature rise, from 60° to 84°F. This
is not representative of many vehicles' travel patterns: Some
vehicles are driven so many times in a day that they never have
the opportunity to experience diurnal emissions; some are driven
in patterns such that they experience diurnal emissions over much
smaller temperature rises than 24 F°; and some vehicles are not
driven at all for two, three, or more consecutive days, leading to
the generation of diurnal evaporative emissions sufficient to
overwhelm canister capacity (since the canister is not purged when
the vehicle is not driven), and thus experience diurnal emissions
that approach or reach uncontrolled (i.e., no evaporative control
canister) levels. This variation in travel patterns has been
incorporated into the emission rates calculated by MOBILE4.
On the basis of analyzing detailed trip pattern information
from a large data base (1979 National Purchasing Diary), estimates
have been developed for the fraction of vehicles that experience
no hot soak emissions in a given day, that experience one full
diurnal emissions cycle (characterized by a temperature rise
corresponding to the input maximum daily temperature minus the
input minimum daily temperature), that experience "multiple"
diurnal emission cycles (on the second or greater consecutive day
of no driving), and that experience "partial" diurnal emission
cycles (e.g., a vehicle that is driven three times in one day,
between 7 and 7:30 AM, again between 12:30 and 1:00 PM, and
finally between 6:00 and 7:00 PM, and thus experiences two diurnal
emission cycles, neither of which is characterized by a
temperature rise as great as that determined as the difference in
the daily maximum and minimum temperatures).
* "Draft Regulatory Impact Analysis for Control of Gasoline
Volatility and Evaporative Hydrocarbon Emissions from New Motor
Vehicles," U.S. EPA, OAR, QMS, July 1987; pp. 2-54 to 2-71.
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1-14
The hot soak and diurnal emissions characteristic of these
different travel patterns are calculated by MOBILE4 and then
weighted together by the fractions of the fleet that experience
each type of condition, based on the trip pattern data base
mentioned above. Partial diurnal emissions are calculated on the
basis of the input minimum and maximum daily temperatures and the
typical variation in temperature over the course of the day.
Multiple diurnal emissions are estimated on the basis of
uncontrolled diurnal emission rates for vehicles of different
types and model year groups. The net result is a considerably
more complicated set of calculations, but also a more accurate
representation of evaporative emissions in real-world situations.
1.1.12 Tampering Effects on Emissions
Several changes have been made in the way that MOBILE4
determines tampering rates and corresponding emissions offsets.
Three such revisions are described below.
An eighth type of tampering, missing gas caps, has been added
to the list of tampering types for which rates of occurrence and
corresponding emission offsets are calculated. The list of
tampering types modeled in MOBILE4 is:
1) air pump disablement
2) catalyst removal
3) overall misfueling
4) fuel inlet restrictor disablement
5) EGR system disablement
6) evaporative control system disablement
7) PCV system disablement
8) missing gas caps.
As described in section 2.2.1, tampering rates are modeled in
an analogous manner to the modeling of basic emission rates, with
a zero-mile level (y-intercept) and deterioration rate (slope),
which together describe the rate of each type of tampering as a
function of vehicle accumulated mileage. EPA's tampering survey
data show that the rates of some types of tampering increase at an
increasing rate after 50,000 miles accumulated mileage. Thus for
LDGVs and LDGTs, there are two deterioration rates, one applicable
to accumulated mileage up to 50,000 miles and one to accumulated
mileage over 50,000 miles.
For some types of tampering, the tampering survey data also
show that distinctly different rates of tampering are seen in 1980
and earlier model year vehicles and in 1981 and later model year
vehicles. This is reflected where applicable in the tampering
rates used in MOBILE4.
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1.1.13 Anti-Tampering Programs
The modeling of anti-tampering program emission benefits has
been revised in MOBILE4. The list of program specifications that
is required of the user in order to model the benefits of such
programs has been revised. The following items must be specified
by the user:
o Start year (calendar year in which the program begins)
o First (earliest) and last (most recent) model years of
vehicles subject to the program
o Whether or not each of four possible vehicle types
(LDGV, LDGT1, LDGT2, HDGV) are covered by the program
o Program type (centralized or decentralized)
o Frequency of inspection (annual or biennial)
o Compliance rate (percent)
o Inspections performed (air system, catalyst, fuel inlet
restrictor, tailpipe lead deposit test, EGR system,
evaporative system, PCV, gas cap)
In MOBILES, the user was also required to supply to the
program as input a set of anti-tampering emission credit
matrices. This is no longer required in MOBILE4, which contains
subroutines that generate the necessary credit matrices on the
basis of the program information specified by the user.
See section 2.2.6 and Appendix 2A for additional information.
1.1.14 Inspection/Maintenance Programs
Several changes have also been made in MOBILE4 to the
modeling of I/M program emission benefits. The list of program
specifications that is required of the user in order to model the
benefits of such programs has been revised. The following items
must be specified by the user:
o Program start year (calendar year that program begins)
o Stringency level (percent)
o First (earliest) and last (latest) model years of
vehicles subject to the requirements of the program
o Waiver rates (percent of failed vehicles; one rate
applicable to pre-model year 1981 vehicles and one
applicable to 1981 and later model year vehicles)
o Compliance rate (percent)
o Program type (centralized; decentralized and
computerized; or decentralized and manual)
o Frequency of inspection (annual or biennial)
o Whether or not each of four possible vehicle types
(LDGV, LDGT1, LDGT2, HDGV) are covered by the program
o Test type (idle, 2500/idle, loaded/idle)
o Whether or not alternate I/M credits are to be supplied
for each of two technology groups (Tech I-II, Tech IV+)
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All standard low-altitude I/M program benefits are contained
in the MOBILE4 code. Standard I/M program benefits for
high-altitude areas are contained on the MOBILE4 tapes supplied by
EPA. For other types of programs, EPA must be contacted for
assistance in developing the appropriate emission credits. For
additional information, see section 2.2.5 and Appendix 2A.
1.3 LIST OF ABBREVIATIONS USED IN THIS DOCUMENT
There are a large number of abbreviations and acronyms used
throughout this document. While efforts have been made to define
all abbreviations and acronyms the first time that they appear,
readers may find the following alphabetized reference list
useful. Further information on those abbreviations representing
MOBILE4 control flags and other variable names appears in the
sections listed at the end of those definitions.
A/C or AC
ALHFLG
alt
amb
AMBT
ANSI
AP
ASCII
ASTM
ASTMCL
ATP
ATPFLG
BER
bpi
CO
CPU
CY
DB
deg
OR
DR1
Air conditioning, air conditioner
Control flag for application of optional additional
corrections to light-duty gasoline-fueled vehicle
emission factors (section 2.1.10)
Altitude
Ambient
Variable name for user-specified ambient
temperature (section 2.3.4)
American National Standards Institute
Airport
American Standard Code for Information Interchange
American Society for Testing and Materials
Variable name for ASTM fuel volatility class
(section 2.2.10)
Anti-tampering program
Control flag for determination of whether effects
of an ATP on emission factors is to be modeled
(section 2.1.11)
Basic emission rate
Bytes per inch
Carbon monoxide
Central processing unit
Calendar year; also, variable name
year of evaluation (section 2.3.2)
for calendar
Dry bulb temperature
Degree(s)
Deterioration rate
Deterioration rate applicable
accumulated mileage
up to 50,000 miles
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DR2
e.f. or EF
EGR
EPA
ft
FTP
FTS
°F
g/BHP-hr
g/hr
g/mi
g/min
GVW
HC
HCFLAG
HDD or HDDV
HDG or HDGV
HDV
ICEVFG
IDLFLG
(FORM
I/M
IMFLAG
Int' I
I/O
IOUNEW
JCL
K
kg
Deterioration rate
accumulated mileage
applicable after 50,000 miles
LAP
Ib,
LDD
LDDT
LDDV
LDG
Ibs
Emission factor(s)
Exhaust gas recirculation
Environmental Protection Agency
Feet
Federal Test Procedure
Federal telephone system
Degrees Fahrenheit
Grams per brake horsepower-hour
Grams per hour
Grams per mile
Grams per minute
Gross vehicle weight
Hydrocarbon(s)
Control flag for determination of HC emission
factors to be included in output (section 2.1.19)
Heavy-duty diesel vehicle(s) (over 8,500 Ibs GVW)
Heavy-duty gasoline-fueled vehicle(s) (over 8,500
Ibs GVW)
Heavy-duty vehicle(s)
Control flag in MOBILES; replaced by HCFLAG
Control flag for output of idle emission factors
(section 2.1.17)
Control flag in MOBILES; replaced by OUTFMT
Inspection and maintenance
Control flag for determination of whether effects
of an I/M program on emission factors is to be
modeled (section 2.1.9)
International
Input/Output
Input record for reassignment of I/O units
(section 2.1.2)
Job control language
Thousand(s) (e.g., 50K = 50,000)
Kilogram(s)
Local area parameter (record) (section 2.2.8)
Pound(s)
Light-duty diesel(s)
Light-duty diesel truck(s) (0-8500 Ibs GVW)
Light-duty diesel vehicle(s)
Light-duty gas
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LDGT
LDGT1
LDGT2
LDGV
LOT
LOV
LOCFLG
max
Mw
min
MPD
mph
MSL
MVMA
myg
MY or MYR
MYMRFG
NAAQS
NEWFLG
NIPER
NMHC
NMHFLG
NOx
NTIS
OAR
OEM
QMS
OUTFMT
PC
PCCC
PCCN
PCHC
PCV
PROJ ID
Light-duty gasoline-fueled truck(s) (0-8500 Ibs GVW)
LDGT(s,' up to 6,000 Ibs GVW
LDGT(S) 6,001-8,500 Ibs GVW
Light-duty gasoline-fueled vehicle(s)
Light-duty truck(s)
Light-duty vehicle(s)
Control flag for location of local area parameter
record in input stream (section 2.1.13)
Maximum
Motorcycle(s)
Minimum
Miles per day
Miles per hour
Mean sea level
Motor Vehicle Manufacturer's Association
Model year group
Model year(s)
Control flag for input of annual mileage
accumulation rate data or registration distribution
data (section 2.1.7)
National Ambient Air Quality Standard
Control flag indicating whether user is entering
modifications to BERs (section 2.1.8)
National Institute for Petroleum and Energy Research
Non-methane hydrocarbons
Control flag indicating whether total HC or NMHC
emission factors are to be calculated
(section 2.1.18)
Oxides of nitrogen
National Technical Information Service
Office of Air and Radiation
Original equipment manufactured/manufacturer
Office of Mobile Sources
Control flag indicating type of formatted output
report to be produced (section 2.1.15)
of VMT accumulated by
in cold-start mode
Personal computer(s)
Variable name for percent
catalyst-equipped vehicles
(section 2.3.5)
Variable name for percent of VMT accumulated by non-
catalyst vehicles in cold-start mode (section 2.3.5)
Variable name for percent of VMT accumulated by
catalyst-equipped vehicles in hot-start mode
(section 2.3.5)
Positive crankcase ventilation
Variable name for MOBILE4 run title (section 2.1.3)
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PROMPT
PRTFLG
psi
R
Reg
RLFLAG
rpm
RVP
SIP
SPDFLG
T
TAMFLG
TCP
Tech I-1 I and
Tech IV+
TEMFLG
temp
TPD
ub
UDI
veh
VMFLAG
VMT
VRS
WB
X
Control flag indicating whether user will be
prompted for remaining MOBILE4 input (section
2.1.1)
Control flag indicating which pollutants are to be
included in output (section 2.1.16)
Pounds per square inch
Refueling HC emission factor label in numeric
formatted output reports (sections 3.3.1, 3.3.2)
Region
Control flag indicating how refueling emission are
to be calculated (section 2.1.12)
Revolutions per minute
Reid vapor pressure
State Implementation Plan
Control flag indicating how average vehicle speed
is to be specified (section 2.1.5)
Running loss HC emission factor label in numeric
formatted output reports (sections 3.3.1, 3.3.2)
Control flag indicating whether alternate
tampering rates are to be input (section 2.1.4)
Temperature correction factor
Technology groupings of vehicles for which
different I/M emission credits have been developed
(section 2A.1.15)
Control flag indicating how temperatures for use
in correcting emission factors are to be
determined (section 2.1.14)
Temperature(s)
Trips per day
Upper bound
Uncontrolled diurnal index
Evaporative HC emission factor label in numeric
formatted output reports (sections 3.3.1, 3.3.2)
Vehicle(s)
Control flag indicating whether alternate VMT
mix(es) will be input (section 2.1.6)
Vehicle miles travelled
Vapor recovery system
Wet bulb temperature
Exhaust HC emission factor label in numeric
formatted output reports (sections 3.3.1, 3.3.2)
ZML
Zero-mile level
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Chapter 2
MOBILE4 INPUTS
2.0 INTRODUCTION
The reader is strongly encouraged to refer to the examples in
Chapter 5 when reading this chapter. The examples provide
illustrations of the use of MOBILE4 options and data input
requirements.
MOBILE4 utilizes one input data set that provides program
control information and the data describing the scenarios for
which emission factors are to be estimated. The input data set
consists of three distinct sections: the Control section, the
One-time data section, and the Scenario section. (In previous
versions of the User's Guide, the Scenario section was referred to
as the Parameter section.)
The Control section is the portion of the input data that
controls the input, output, and execution of the program. For
example, the Control section indicates whether MOBILE4 will prompt
the user for input data, or analyze a scenario that includes an
inspection and maintenance program, or output the emission factors
in a format suitable for visual inspection or in a format suitable
as input for another program.
Certain of the parameters used in the emission factor
calculations have internal, or default, values built into
MOBILE4. The One-time data section is the portion of the input
data that allows the user to define parameter values different
from those internal to MOBILE4, which will be used in the
calculations for all of the scenarios within a given run. For
example, in the One-time data section the user can specify annual
mileage accumulation rates or registration distributions by age
for each vehicle type.
The Scenario section is the portion of the MOBILE4 input data
that details the individual scenarios for which emission factors
are to be calculated. For example, in the Scenario section the
user specifies the calendar year of evaluation, the average
speed(s) to be assumed, and the region (low- or high-altitude).
In a few cases, the placement of data in either the One-time
data section or the Scenario data section is determined by the
setting assigned to a flag in the Control section of the input
stream. In such cases, discussion of the variable(s) involved is
provided once, in the One-time data section, and that discussion
is referenced in the Scenario data section.
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2-2
The Control section consists primarily of specified values
for variables termed flags. In section 2.1 each flag is named,
and the range of possible settings for that flag and the resulting
action is noted. In the One-time and Scenario data sections
(sections 2.2 and 2.3 respectively), the following general format
is used. (Depending on the variable being discussed, not every
item noted below is included for every variable.)
o Description: A brief description of what the variable
means, and how it is used by MOBILE4.
o Options: A summary of choices available to the MOBILE4
user.
o Use in MOBILE4: A description of the value(s) used in
MOBILE4 for the variable(s) if the user does not input locality-
specific information, where applicable, and discussion of how the
information is used in the emission factor calculations.
o Recruired Information: A specific description of
exactly what information is required of the user, where
applicable, including format specifications.
o Guidance: Where applicable, EPA's recommendations and
suggestions with respect to the determination of user-supplied
values for the variable(s) under discussion. Many users of
MOBILE4 will be involved in the development of emission
inventories and projections for use in the State Implementation
Plan (SIP) process. In many cases, there is no single correct
answer or recommendation that will be the best answer for all
areas. For those using MOBILE4 for SIP-related purposes, it is
important that the appropriate EPA Regional Office personnel be
kept involved in decisions concerning questionable or
controversial assumptions and steps in the modeling.
There are also three appendices to this chapter which provide
additional information about some of the variables, their use
within MOBILE4, and the determination of locality-specific
information for use as input data. All of the tables referred to
in the text are grouped together at the end of the chapter for
ease of reference by the user.
Questions about the material in this document, and
suggestions as to how the MOBILE4 User' s Guide may be made clearer
and more useful, should be addressed to:
Terry P. Newell (TEB-13)
U.S. EPA Motor Vehicle Emission Laboratory
2565 Plymouth Road
Ann Arbor, MI 48105
(313) 668-4462 or FTS 374-8462
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2-3
2.1 CONTROL SECTION
The first portion of the input stream for a MOBILE4 run
consists of a series of flag settings. These flags control the
format (and in some- cases the content) of the remainder of the
input stream, influence the execution of the program, and
ietermine the content and format of the program's output. Each
:lag is named, defined, and its possible values listed, along with
cne effect of each possible setting.
2.1.1 PROMPT
2.1.1.1 Description
This flag determines whether the user will be prompted for
the remainder of the input stream, and the arrangement of the
remaining Control data section input. This flag was called IPROMT
in MOBILES.
2.1.1.2 Values/Actions
This flag can be set to 1, 2, 3, or 4:
Value Action
1 No prompting; after PROJID record (see section
2.1.3), vertical format (one value per line/
record) used for remainder of Flags input
2 MOBILE4 prompts for each input; vertical format
3 No prompting; after PROJID record, horizontal
format (all values on one line/record) used for
remainder of Flags input
4 MOBILE4 prompts for each input; horizontal format
It is suggested that the input prompting options (PROMPT = 2 or 4)
be used only when the user is uncertain as to the order of the
remaining inputs in the Control data section.
2.1.2 IOUNEW
2.1.2.1 Description
The IOUNEW flag allows reassignment of output unit device
numbers. There are three different types of program output, and
the default value for all three is unit 6.
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2.1.2.2 Values/Actions
The three types of program output are: formatted reports
(emission factor results), diagnostic messages (error and warning
messages), and prompting messages (such as are issued if the value
cf the PROMPT flag described above is 2 or 4). Single integer
values representing other I/O device numbers may be assigned for
any or all of these, in the order listed. If no device
reassignments are desired, these fields may be left blank.
Values of 1, 2, 3, 6, 7, and 8 are allowed by MOBILE4 for
assignment of any of the three possible output units. Values of 4
and 5 are reserved as input device codes in MOBILE4, and thus may
not be assigned by the user for any IOUNEW field. If an illegal
or missing IOUNEW value is encountered, MOBILE4 will revert to the
default value (unit 6). The user is cautioned that IOUNEW values
considered valid by MOBILE4 may not be appropriate for a given
computer system.
2.1.3 PROJID
2.1.3.1 Description
MOBILE4 provides an 80-character alphanumeric field for the
user to input a descriptive title for the MOBILE4 run.
2.1.3.2 Values/Action
The project title is an 80-column blank record. The user may
use up to 80 characters for the title, and the character string
does not have to be left-justified. Whatever title is input by
the user is simply echoed as the heading of the formatted reports
section of the program output. If no title is desired by the
user, a blank record must be entered here.
2.1.4 TAMFLG
2.1.4.1 Description
This flag provides the option of supplying tampering rates
that differ from those included in MOBILE4.
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2.1.4.2 Values/Action
This flag can be set to l or 2:
Value Action
1 Use MOBILE4 tampering rates
2 User supplies tampering rates for eight categories
of tampering, for each of the four vehicle types
affected by tampering (LDGV, LDGT1, LDGT2, HDGV)
The user-supplied tampering rate data, reguired if TAMFLG = 2, are
placed in the One-time data section. Section 2.2.1 discusses
tampering rates as program input.
2.1.5 SPDFLG
2.1.5.1 Description
MOBILE4 reguires that vehicle speed be specified as part of
the program input, since exhaust emissions vary considerably with
speed. This flag provides the option of specifying one speed for
all eight vehicle types, or of specifying different speeds for
each vehicle type.
2.1.5.2 Values/Action
This flag can be set to 1 or 2:
Value Action
1 User supplies one value for speed to be applied to
all vehicle types
2 User supplies eight values for speed, one to be
applied to each vehicle type
In both cases, the speed input data are placed in the Scenario
data section. Section 2.3.3 discusses speed as program input.
2.1.6 VMFLAG
2.1.6.1 Description
The setting of VMFLAG determines the vehicle miles travelled
(VMT) mix (fraction of total VMT accumulated by vehicles of each
of the eight types) that will be used in MOBILE4 to estimate the
composite emission factor for a given scenario.
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2.1.6.2 Values/Action
This flag can be set to 1, 2, or 3:
Value Action
1 Use MOBILE4 VMT mix
2 User supplies a different VMT mix for each scenario
3 User supplies a single VMT mix for all scenarios
If VMFLAG = 2, the VMT mixes are placed in the Scenario data
section. If VMFLAG = 3, the VMT mix is placed in the One-time
data section. Sections 2.2.2 and 2.3.6 discuss VMT mix as program
input.
2.1.7 MYMRFG
2.1.7.1 Description
This flag controls the use of annual mileage accumulation
rates by age and registration distributions by age. These
parameters define the composition and travel characteristics of
the fleet, and so affect the resulting emission factors.
2.1.7.2 Values/Action
This flag can be set to 1, 2, 3, or 4:
Value Action
1 Use MOBILE4 (national average) annual mileage
accumulation rates and registration distributions
2 User supplies annual mileage accumulation rates;
use MOBILE4 registration distributions
3 User supplies registration distributions; use
MOBILE4 annual mileage accumulation rates
4 User supplies both annual mileage accumulation
rates and registration distributions
The input data reg\iired if MYMRFG = 2, 3, or 4 are placed in the
One-time data section. Section 2.2.3 discusses the input and use
of annual mileage accumulation rates and registration
distributions.
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2.1.8 NEWFLG
2.1.8.1 Description
This flag provides the option of modifying the basic exhaust
emission rates by model year.
2.1.8.2 Values/Action
This flag can be set to either 1 or 2:
Value Action
1 Use MOBILE4 basic exhaust emission rates
2 User supplies one or more modifications to the
MOBILE4 basic exhaust emission rates
The user-supplied modifications to the basic emission rates,
required if NEWFLG = 2, are placed in the One-time data section.
Section 2.2.4 discusses basic exhaust emission rates and their
modification by the user.
2.1.9 IMFLAG
2.1.9.1 Description
This flag allows the option of having MOBILE4 include the
effects of an operating inspection and maintenance (I/M) program
on the emission factors.
2.1.9.2 Values/Action
This flag can be set to 1 or 2:
Value Action
1 No I/M program is assumed to be operating
2 User specifies an I/M program and MOBILE4 models
its impact on emission rates
The data specifying an I/M program, reguired if IMFLAG = 2, are
placed in the One-time data section. Section 2.2.5 discusses the
specification of I/M programs and their use in MOBILE4.
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2.1.10 ALHFLG
2.1.10.1 Description
This flag provides the ability to have MOBILE4 correct some
exhaust emission factors to account for certain conditions: air
conditioning (A/C) usage, extra loading, trailer towing, and
humidity. These additional corrections apply only to exhaust
emission factors (HC, CO, and NOx), and only to the light-duty
gasoline-fueled vehicle types (LDGVs, LDGTls, and LDGT2s), with
the exception that the humidity correction affects only NOx
emission factors and is also applied to motorcycle emissions.
2.1.10.2 Values/Action
This flag can be set to 1, 2, or 3:
Value Action
1 Do not apply these additional correction factors
(no additional inputs required)
2 Six additional input values required
3 Ten additional input values required
The additional data required if ALHFLG = 2 or 3 are placed in the
Scenario data section. The specific inputs required when
ALHFLG = 2 or 3 are discussed in section 2.3.8.
2.1.11 ATPFLG
2.1.11.1 Description
This flag allows for the effects of an operating anti-
tampering program (ATP) to be included in the emission factor
calculations.
2.1.11.2 Values/Action
This flag can be set to 1 or 2:
Value Action
1 No ATP is assumed
2 User specifies an ATP and MOBILE4 accounts for
its impact on emission rates
The data specifying the characteristics of the ATP to be modeled,
required when ATPFLG = 2, are placed in the One-time data
section. Section 2.2.6 discusses user specification of ATPs.
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2.1.12 RLFLAG
2.1.12.1 Description
This flag controls whether and how MOBILE4 models refueling
emissions from gasoline-fueled vehicles. (These emissions are
also referred to as Stage II emissions.) The inclusion of these
emissions, and the RLFLAG flag, are new to MOBILE4.
2.1.12.2 Values/Action
This flag can be set to 1, 2, 3, 4, or 5:
Value Action
1 Use uncontrolled refueling emission rates for
all model years
2 Model the impact of Stage II vapor recovery
system (VRS) requirement on refueling emissions
3 Model impact of onboard VRS requirement on
refueling emissions
4 Model impact of both Stage II and onboard VRS
requirements on refueling emissions
5 Zero-out refueling emissions completely
(effectively the approach taken in MOBILES); in
this case, Stage II emissions must be accounted
for in the stationary source portion of the
emission inventory
The data describing the characteristics of either or both vapor
recovery systems, required if RLFLAG = 2, 3, or 4, are placed in
the One-time data section. Refueling emissions and their modeling
in MOBILE4 are discussed in section 2.2.7.
2.1.13 LOCFLG
2.1.13.1 Description
This flag controls the input by the user of the local area
parameters (LAP) record. This record contains seven variables
(scenario name, ASTM volatility class, minimum and maximum daily
temperatures, base RVP, in-use RVP, and in-use start year).
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2.1.13.2 Values/Action
This flag can be set to 1 or 2:
Value Action
1 User enters a distinct LAP record for each
scenario of the MOBILE4 run
2 User enters one LAP record to apply to all
scenarios of the MOBILE4 run
If LOCFLG = 1. the LAP records are placed in the Scenario data
section. If LOCFLG = 2, the LAP record is placed in the One-time
data section. The content of the LAP is discussed in section
2.2.8, and the individual variables comprising the LAP are
discussed in sections 2.2.9 through 2.2.13. Table 2.2-5 provides
a summary of and specifications for the LAP record in the MOBILE4
input stream.
2.1.14 TEMFLG
2.1.14.1 Description
This flag controls the determination of temperatures to be
used in the correction of the exhaust emission factors (HC, CO,
and NOx), the hot soak and diurnal components of the evaporative
HC emission factors, and the running loss HC emission factors.
All of these are dependent on temperature, although in MOBILES
only the exhaust emission factors were corrected for temperature.
This flag and the features it controls are completely new in
MOBILE4.
2.1.14.2 Values/Action
This flag can be set to 1 or 2:
Value Action
1 MOBILE4 will determine the temperatures to be
used in correcting emission factors for
temperature effects, on the basis of the user-
supplied input values for minimum and maximum
daily temperature. The user-supplied input
value for ambient temperature will not be used
in calculating temperature corrections to
emissions if TEMFLG =1; it will be overridden
by specific values calculated individually for
exhaust HC, exhaust CO, exhaust NOx, hot soak
evaporative HC, and running loss HC.
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Value Action
2 The user-supplied input value for ambient
temperature will be used as the basis for
calculating the temperature corrections to all
exhaust emissions, hot soak evaporative
emissions, and running loss emissions. The
user-supplied input values for minimum and
maximum daily temperature will still be used in
calculating diurnal evaporative emissions.
As discussed in sections 1.1.4 and 1.1.11, the temperatures
used to correct exhaust, hot soak evaporative, and running loss
emissions are determined in a way that accounts for variation in
emission levels with daily variation in temperature if TEMFLG = 1.
The result is that the temperature corrections will be weighted to
reflect average emissions over a period of time (i.e., a day)
where the temperature range is from the minimum to the maximum
input temperatures. Thus, the use of TEMFLG = 1 is recommended
for inventory preparation and SIP-related modeling by the States.
Additional discussion of the use of this new flag and its
impact on the emission factor calculations is in section 1.1.4.
The input of ambient temperature is discussed in section 2.3.4.
The input of minimum and maximum daily temperatures is discussed
in section 2.2.11. Additional guidance on the determination of
appropriate values for use as temperature inputs to MOBILE4 when
the model is being used for SIP-related emission inventory
development and attainment planning is provided in Appendix 2-C of
this User's Guide.
Table 2.1-1 summarizes the flags controlling the input
requirements and execution of MOBILE4.
2.1.15 OUTFMT
2.1.15.1 Description
This flag controls the format structure of the formatted
output report. Different formats are appropriate depending on the
intended use of the MOBILE4 output. This flag was called IFORM in
MOBILES.
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2.1.15.2 Values/Action
This flag can be set to 1, 2, 3, or 4:
Value Action
1 221-column numerical format
2 140-column numerical format
3 112-column descriptive format
4 80-column descriptive format
The numerical formats are generally used when the output of the
MOBILE4 run is to be used as input for another program (e.g. , air
quality simulations). The descriptive formats contain all of the
same information, with more complete labels and headings for ease
of visual inspection. Illustrative examples are shown in
Chapter 5 (MOBILE4 Examples).
2.1.16 PRTFLG
2.1.16.1 Description
This flag determines which pollutants will have emission
factor calculations performed, and thus will be included in the
program output. This feature enables the user to avoid the time
and expense of calculating all emission factors when the results
for only one of the pollutants are all that is necessary for some
applications.
2.1.16.2 Values/Action
This flag can be set to 1, 2, 3, or 4:
Value Action
1 HC (hydrocarbon) emission factors only
2 CO (carbon monoxide) emission factors only
3 NOx (oxides of nitrogen) emission factors only
4 All three pollutants
2.1.17 IDLFLG
2.1.17.1 Description
This flag controls the calculation and output of idle
emission factors (emissions at idle in terms of mass pollutant per
unit time (g/hr) for each pollutant).
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2.1.17.2 Values/Action
This flag can be set to 1 or 2:
Value Action
1 No idle emission factors calculated or printed
(exhaust emission factors only)
2 Idle emission factors calculated and printed
(in addition to exhaust emission factors)
2.1.18 NMHFLG
2.1.18.1 Description
This flag determines whether the HC emission factors will be
calculated on the basis of total hydrocarbons (including methane),
or only for non-methane hydrocarbons (NMHC). This feature is
useful when only reactive (i.e., non-methane) HC emission factors
are desired.
2.1.18.2 Values/Action
This flag can be set to 1 or 2:
Value Action
1 Total hydrocarbon emission factors
2 Non-methane hydrocarbon emission factors
2.1.19 HCFLAG
2.1.19.1 Description
This flag determines whether the HC emission factors in the
output will include only the total HC emissions (whether total or
non-methane, as discussed above), or will also include component
emission factors (exhaust, evaporative, refueling, running loss,
and total HC emissions). This flag is new in MOBILE4, and
provides the user one of the options previously accessed through
the ICEVFG flag, which no longer exists.
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2.1.19.2 Values/Action
This flag can be set to 1 or 2:
Value Action
1 No component output (print only total HC)
2 Print components (exhaust, evaporative,
refueling, running loss, and total HC)
Table 2.1-2 summarizes the flags controlling the output of MOBILE4.
2.1.20 Inter-Flag Dependencies
2.1.20.1 Description
There are cases where the value assigned to one flag in the
Flags section either determines the value that must be assigned to
another flag, or precludes the use of one or more possible values
for another flag. Certain combinations of flag settings also
impose requirements on other inputs in either the One-time or
Scenario data sections. While careful consideration of the inputs
prepared for a MOBILE4 run makes such situations clear, a short
listing is provided here for the convenience of the user.
2.1.20.2 List
2.1.20.2.1 If TAMFLG = 2 (user-supplied tampering rates) and
IMFLAG = 1 (no I/M program assumed), supply only
one set of alternate tampering rates (non-I/M
rates).
2.1.20.2.2 If TAMFLG = 2 and IMFLAG = 2 (specify and model
an I/M program), two sets of alternate tampering
rates must be supplied (both non-I/M and I/M
rates).
2.1.20.2.3 If PRTFLG = 2 or 3 (no HC emission factors
requested), then the flags dealing with details
of the HC emission factor calculation should be
set as follows: NMHFLG = 1, HCFLAG = 1, and
RLFLAG = 5.
2.1.20.2.4 Conversely, if NMHFLG = 2 (calculate non-methane
HC emission factors) and/or HCFLAG = 2 (print
components of HC emission factor) and/or
RLFLAG =1, 2, 3, or 4 (calculate refueling
emissions), then PRTFLG = 1 or 4 is necessary.
This concludes the Control data section.
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2.2 ONE-TIME DATA SECTION
As suggested by its name, the One-time data section contains
information which is input only once in MOBILE4. This input
information is used to alter internal MOBILE4 estimates to be
locality-specific. For example, a user can incorporate VMT mix,
mileage accumulation, and/or registration distributions that are
specific to the area of concern. These records are all optional,
their use being dictated by the values of some of the flags in the
Control section. (Thus, in some MOBILE4 runs the One-time data
section will not be included in the input sequence.) If any of
these records are included in the input, they follow immediately
after the Control section, in the order in which they are
described below.
The One-time data section must be included if one or more of
the following MOBILE4 options are selected:
1. The user wishes to input local tampering parameters
(TAMFLG = 2) .
2. The user wishes to supply a VMT mix which will be
applied to all emission factor calculations
(VMFLAG = 3).
3. The user wishes to use local mileage accumulation
and/or registration distributions by age
(MYMRFG = 2, 3, or 4).
4. The user wishes to modify the basic exhaust emission
rates used in the calculation of the emission estimates
(NEWFLG = 2) .
5. The user wishes to include Inspection/Maintenance
credits in the emission factor calculations
(IMFLAG = 2).
6. The user wishes to include the effects of an
anti-tampering program in the emission rates
(ATPFLG = 2).
7. The user wishes to include the effects of Stage II or
onboard vapor recovery systems on the refueling HC
emission factors (RLFLAG = 2, 3, or 4).
8. The user wishes to have the same local area parameter
(LAP) record input values applied to all scenarios of a
MOBILE4 run (LOCFLG =2).
The data requirement order in the One-time data section is
the same order as the associated flags in the Control section.
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2.2.1 TAMPERING RATES
2.2.1.1 Description
MOBILE4 calculates tampering rates as a piecewise linear
function of accumulated mileage for each gasoline-fueled vehicle
type (LDGV, LDGT1, LDGT2, and HDGV) and for eight types of
tampering (air pump disablement, catalyst removal, overall
misfueling, fuel inlet restrictor disablement, EGR system
disablement, evaporative control system disablement, PCV system
disablement, and missing gas caps). These rates are combined with
the corresponding fractions of vehicles equipped with the given
control technology and the emissions impact rates to obtain the
tampering offsets (the increase in emissions that results from the
given type of tampering). These offsets are subsequently added to
the non-tampered emission factors.
2.2.1.2 Options
MOBILE4 uses tampering rates based on QMS analysis of
multi-city tampering survey results if no locality-specific rates
are supplied as input (TAMFLG = 1). The use of the rates
i ncIuded i n MOB ILE4 i s recommended.
Provisions exist within MOBILE4 for the input of alternate
tampering rates (TAMFLG = 2). EPA has determined through its
tampering surveys that tampering rates are lower in areas with
operating inspection and maintenance (I/M) programs than in areas
without such programs, and are lower after an I/M program is
implemented in a given area than in the same area before the
program begins operation. Thus, if TAMFLG = 2 and IMFLAG, = 1, the
user must supply one set of alternate rates, representing the case
where no inspection and maintenance (I/M) program is in effect.
If TAMFLG = 2 and IMFLAG = 2, the user must supply two sets of
alternate rates, representing both the non-I/M and I/M cases.
Before approving the use of alternate tampering rates, EPA must
review and approve of the tampering survey(s) on which such rates
are based.
2.2.1.3 MOBILE4 Tampering Rates
MOBILE4 uses two or four rate equations for each type of
tampering stored within the model, for each of the vehicle types
subject to tampering (one each for pre-1981 model year vehicles
and for 1981 and later model year vehicles; for either the non-I/M
case only, or for both the non-I/M and I/M cases). These rate
equations are based on QMS analysis of national tampering survey
data.
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2.2.1.4 Required Information
The following information is required in order to input
alternate tampering rates: For each combination of (vehicle
type)/(pre-1981 model year or 1981 and later model year)/
(tampering type)/(non-I/M or I/M case), you must supply a zero-
mile level (y-intercept) and deterioration rate (slope, or rate of
increase in the tampering rate per 10,000 miles accumulated
mileage). For 1981 and later model year light-duty gasoline-
fueled vehicles (LDGVs) and light-duty gasoline-fueled trucks
(LDGTls and LDGT2s), a second deterioration rate is also required
that defines the rate of increase in the tampering rates for such
vehicles after 50,000 miles accumulated mileage. All values must
be in fractional units.
The required format for each of the sets of rates (either one
or two sets, as discussed in section 2.2.1.2) is:
For pre-1981 model year vehicles: 8F8.4, 8F9.5.
For 1981 and later model year vehicles: 8F8.4, 8F9.5, 8F9.5.
The 8F8.4 record is for the zero-mile levels. The 8F9.5 record(s)
are for the deterioration rates. For 1981 and later, two sets of
deterioration rates are required (up to 50,000 miles, 50,000 miles
and higher accumulated mileage, as discussed above). The order of
the tampering types within each record is:
1) air pump disablement
2) catalyst removal
3) overall misfueling
4) fuel inlet restrictor disablement
5) EGR system disablement
6) evaporative control system disablement
7) PCV system disablement
8) missing gas caps.
Thus the complete set of alternate tampering rate data
inputs, for the non-I/M case and for the I/M case, consists of a
total of 20 records: For each of the four gasoline-fueled vehicle
types (LDGV, LDGT1, LDGT2, HDGV, in that order), there are four
records, except for LDGV there are five:
1) ZML for pre-1981 model year vehicles (8F8.4)
2) DR for pre-1981 model year vehicles (8F9.5)
3) ZML for 1981 and later model year vehicles (8F8.4)
4) DR1 for 1981 and later model year vehicles (8F9.5)
5) DR2 for 1981 and later model year vehicles (8F9.5)
where DR1 are applied up to 50,000 miles accumulated mileage and
DR2 are applied after 50,000 miles accumulated mileage for LDGVs
(for other vehicle types, DR1 is applied regardless of mileage).
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2.2.1.5 Guidance
For guidance regarding EPA approval of tampering surveys and
the development of tampering rates based on such surveys, contact
the Office of Mobile Sources (Field Operations and Support
Division, 202/382-2633 or FTS 382-2633).
2.2.2 VEHICLE MILES TRAVELLED MIX by vehicle type
2.2.2.1 Description
The vehicle miles travelled (VMT) mix specifies the fraction
of total highway VMT that is accumulated by each of the eight
regulated vehicle types. The VMT mix is used by MOBILE4 only to
calculate the composite (all vehicle, or fleetwide) emission
factor for a given scenario from the eight vehicle-class-specific
emission factors.
2.2.2.2 Options
You can choose between the use of the MOBILE4 national VMT
mix (VMFLAG = 1), the input of one locality-specific VMT mix for
use in all scenarios of a given MOBILE4 run (VMFLAG = 3), or the
input of a distinct locality-specific VMT mix for each scenario
(VMFLAG =2).
For inventory construction purposes, EPA generally will
requires states to develop and use their own specific estimates of
VMT by vehicle type. In such cases, VMT fractions based on those
estimates of VMT by vehicle type should be calculated and used
here as input.
2.2.2.3 MOBILE4 VMT Mix
MOBILE4 calculates the VMT mix based on national data
characterizing registration distributions and annual mileage
accumulation rates by age for each vehicle type, diesel sales
fractions by model year (for LDVs and LDTs only), total HDDV
registrations and annual mileage accumulations by weight class,
and total vehicle counts (fleet size) by vehicle type.
Considering the dependance of the VMT mix on the annual mileage
accumulation rates and registration distributions by age (see
section 2.2.3), the use of the MOBILE4 VMT mix is generally
recommended in cases where the focus is on direct comparison of
emission factors under different assumptions.
As noted above, for inventory construction states will
generally develop and apply their own estimates of VMT by vehicle
type. The use of an alternate VMT mix will result in minor
internal inconsistencies; for example, assumptions concerning the
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gas/diesel split of LDVs that are used in the emission factor
calculations will not be altered through the use of different VMT
fractions for LDGVs and LDDVs. However, such inconsistencies will
not significantly affect inventory construction unless the
inventory is based only on the fleetwide composite emission factor
and total mobile source VMT. Inventory construction based on
vehicle-type-specific emission factors and VMT estimates, as EPA
will require of States for SIP purposes, will not use the
composite fleetwide emission factor.
2.2.2.4 Required Information
Each VMT mix supplied as input must consist of a set of eight
fractional values, representing the fraction of total mobile
source VMT accumulated by each of the eight vehicle types. All
values must be between zero and one (0.0 _<_ VMT fraction for any
vehicle type <^ 1.0), and the eight values must sum to 1.0 (MOBILE4
will output an error message and will not execute the run if these
constraints are not met).
The format of the VMT mix record(s) is 8F4.3. The values
correspond to the eight vehicle types in this order: LDGV, LDGT1,
LDGT2, HDGV, LDDV, LDDT, HDDV, and MC.
2.2.2.5 Guidance
Techniques for calculating estimated VMT by vehicle type (and
thus, total VMT and the VMT mix fractions) from available data
sources are described in Chapter 6 of the report, "Techniques for
Estimating MOBILE2 Variables."*
2.2.3 ANNUAL MILEAGE ACCUMULATION RATES and/or REGISTRATION
DISTRIBUTIONS by vehicle type and age
2.2.3.1 Description
MOBILE4's emission factor calculations incorporate estimates
of the average annual mileage accumulation by age (first year to
20th-and-greater years of operation) for each of the eight vehicle
types, and the registration distribution by age (age 0-1 to age
19-20+) for each vehicle type, except motorcycles, for which
annual mileage accumulation rates and registration distributions
are only provided for the first to 12th-and-greater years of
operation (ages 0-1 to 11-12+).
2.2.3.2 Options
MOBILE4 uses national average annual mileage accumulation
rates by age and registration distributions by age, and has
See section 2.5 for information on obtaining referenced reports.
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provisions allowing the input of locality-specific data for either
or both of these. The use of the annual mileage accumulation
rates by age included in MOBILE4 is strongly recommended. Users
may develop registration distributions by age on the basis of
locality-specific data.
2.2.3.3 MOBILE4 Annual Mileage Accumulation Rates and
Registration Distributions
If you do not provide locality-specific mileage accumulation
rates and/or registration distributions by age, MOBILE4 uses
national average values.
This information is used for all calendar years evaluated,
and is based on analyses of information developed over a long
period of time. Due to the importance of this information in
characterizing the in-use fleet, the need to avoid basing such
information on data collected over a short period of time (thereby
increasing the risk of reflecting atypical or cyclical use or sale
patterns), and the inherent difficulty of developing accurate
locality-specific data describing annual mileage accumulation
rates by age, the use of the MOBILE4 annual mileage accumulation
rates by age is recommended. The use of locality-specific data to
derive registration distributions by age may be appropriate for
some applications, particularly where such data reflect
significant differences from the national average.
If local annual mileage accumulation rates or registration
distributions are used, they normally should not change across
calendar years. In particular, EPA will not accept SIP-related
modeling that includes assumptions that the vehicle fleet will be
newer (have a lower average age) in the future than is reflected
in the MOBILE4 registration distributions. Modeling that assumes
no further aging of the fleet from the current characterization
will be accepted by EPA for SIP purposes.
2.2.3.4 Repaired Information
These records are reguired if MYMRFG = 2, 3, or 4 (see
section 2.1.7).
To use locality-specific annual mileage accumulation rates by
age, a total of 160 input values are reguired: the estimated
annual mileage accumulated by vehicles of each of the eight types
for each of 20 ages (except 12 ages for motorcycles; use 0.0 as
the annual mileage accumulation rate for motorcycles of ages 13
through 20). These values are input as miles divided by 10,000
(e.g., 12,637 miles is input as 0.12637).
To use locality-specific registration distributions by age,
again a total of 160 input values are required. For each vehicle
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type, a set of 20 values (except 12 values for motorcycles; use
0.0 as the registration distribution for motorcycles of ages 13
through 20) are required to represent the fraction of all vehicles
of the given type that are of a given age.
Any individual value must be between zero and one. The
values for LDGVs and LDDVs must be equal, and the values for
LDGTls and LDDTs must be equal. MOBILE4 uses an internal function
to separate these pairs of vehicle types into distinct gas and
diesel distributions, based on diesel sales fractions by model
year. Thus, the sums of either of these two sets of values:
LDGV + LDGT1 + LDGT2 + HDGV + HDDV + MC
or
LDGT2 + HDGV + LDDV + LDDT + HDDV + MC
should equal 1.0.
In addition, in the case where you supply both the annual
mileage accumulation rates by age and the registration
distributions by age, the annual mileage accumulation rate
corresponding to any vehicle type/age combination accounting for a
non-zero fraction of registrations must be positive (i.e., if
vehicles of a certain type and age exist in the fleet, then they
must accumulate some mileage). If these constraints are not met,
MOBILE4 will generate one or more error messages and the run will
be aborted.
The annual mileage accumulation rates are entered as 16
records, each of 10F7.5 format. Registration distributions by age
are also entered as 16 records, each of 10F5.3 format. If both
annual mileage accumulation rates and registration distributions
are being supplied by the user, the annual mileage accumulation
rates precede the registration distributions (16 records of format
10F7.5 followed by 16 records of format 10F5.3).
In both cases, the 16 records represent 2 records per vehicle
type for each of the eight vehicle types, in this order: LDGV,
LDGT1, LDGT2, HDGV, LDDV, LDDT, HDDV, and MC. Each of the two
records per vehicle type contains the annual mileage accumulation
rate by age, or the registration distribution by age, as follows:
First record - age 1, age 2, age 3, . . . , age 10
Second record - age 11, age 12, age 13, . . . , age 20+.
2.2.3.5 Guidance
Methods for estimating the annual mileage accumulation rates
by age and the registration distributions by vehicle type and age
are presented in Chapters 2 and 3, respectively, of the report
"Techniques for Estimating MOBILE2 Variables."
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2.2.4 BASIC EMISSION RATES
2.2.4.1 Description
The basic emission rates (BERs) in MOBILE4 are expressed in
the form of equations, consisting of a zero-mile level (ZML)
(y-intercept) and deterioration rate (DR) (slope, or increase in
emissions per 10,000 miles accumulated mileage). The units used
for all vehicle types except heavy-duty vehicles (HDGV, HDDV) are
grams per mile (g/mi) for the ZMLs and g/mi per 10,000 miles (g/mi
per 10K mi) for the DRs. For HDGVs and HDDVs, the units are grams
per brake horsepower-hour (g/BHP-hr). There are different BER
equations in MOBILE4 for each vehicle type/pollutant/model year
group, with the model year groups defined on the basis of
applicable emission standards and control technologies used.
A feature new to MOBILE4 is the inclusion of two different
deterioration rates in each BER equation for certain vehicle types
and model year groups. In each such BER equation, there is one DR
applicable to mileage accumulated between zero and 50,000 miles,
and a second (higher) DR applicable to mileage accumulated beyond
50,000 miles. This feature is applicable only to 1981 and later
model year LDGVs.
2.2.4.2 Options
MOBILE4 provides the capability to input alternate BER
equations (NEWFLG = 2). However, the BERs in MOBILE4 accurately
reflect all promulgated emission standards; no locality-specific
changes to these equations are warranted. The option of
alternate BERs is intended for use only in the situation where
new or revised emission standards are promulgated by EPA after the
release of MOBILE4.
2.2.4.3 MOBILE4 Basic Emission Rates
The BER equations in MOBILE4 are based on the applicable
Federal emission standards and the emission control technologies
characterizing the fleet in various model years (for example,
different types of catalytic converters exhibit different rates of
deterioration). These equations are applicable for all non-
California areas, both low- and high-altitude, and should not be
altered by the user without EPA guidance.
2.2.4.4 Required Information
If alternate BER equations are to be used, the information
that must be supplied includes: the number of alternate BER
equations that are to be entered, the region (low- or high-
altitude) to which the alternate BERs apply, the vehicle type(s)
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affected, the first and last model years for which the alternate
equations apply, the ZML (g/mi), and the DR (g/mi per 10K mi).
If the vehicle type affected is 1981 and later model year
LDGVs, then two DRs (one for accumulated mileage up to 50,000 mi
and one for accumulated mileage beyond 50,000 mi) must be
supplied. This is new in MOBILE4. If the vehicle type affected
is HDGV or HDDV, units of g/BHP-hr must be used for both ZML and
DR. This is also new in MOBILE4, which will convert the g/BHP-hr
rates to g/mi rates internally.
The new BER input must consist of a set of N+1 records,
where N is the number of new BERs (records) that follow the
first record. The maximum number of new BERs permitted in a
MOBILE4 run is 100. In addition, for each combination of region/
vehicle type/pollutant, no more than 12 new BERs are permitted.
The format specifications, allowable ranges, and codes for these
records are summarized in Table 2.2-1.
2.2.4.5 Guidance
If you require the use of alternate BER equations in the
future, you should contact the Office of Mobile Sources for
additional guidance (Test and Evaluation Branch, 313/668-4325 or
FTS 374-8325).
2.2.5 INSPECTION AND MAINTENANCE PROGRAMS
2.2.5.1 Description
Many areas of the country have implemented inspection and
maintenance (I/M) programs as a means of further reducing mobile
source air pollution. MOBILE4 has the capability of modeling the
impact of an operating I/M program on the calculated emission
factors.
2.2.5.2 Options
The user has the option of either accounting for the effects
of an I/M program (IMFLAG = 2), or of assuming that there is no
I/M program in effect (IMFLAG = 1). Standard low-altitude area
emission reduction credits are contained in the MOBILE4 code, and
standard high-altitude area emission credits are included as a
separate file on the MOBILE4 tape. The model is also capable of
accepting alternate credit matrices developed by EPA as input data.
2.2.5.3 Required Information
If IMFLAG = 2, all of the following I/M program parameters
must be specified by the user, in the order shown:
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o Program start year (calendar year that program begins)
o Stringency level (percent)
o First (earliest) and last (latest) model years of
vehicles subject to the requirements of the program
o Waiver rates (percent of failed vehicles; one rate
applicable to pre-model year 1981 vehicles and one
applicable to 1981 and later model year vehicles)
o Compliance rate (percent)
o Program type (centralized; decentralized and
computerized; or decentralized and manual)
o Frequency of inspection (annual or biennial)
o Whether or not each of four possible vehicle types
(LDGV, LDGT1, LDGT2, HDGV) are covered by the program
o Test type (idle, 2500/idle, loaded/idle)
o Whether or not alternate I/M credits are to be supplied
for each of two technology groups (Tech I-II, Tech IV+)
The format of this record is:
4(12,IX),2(F2.0,1X),F3.0,1X,2(I1,1X),411,IX,II,IX,211.
Table 2.2-2 summarizes the I/M descriptive input record
required if IMFLAG = 2, including the codes and allowable values
for each field of the record. See Appendix 2A of this chapter for
more detailed discussion of each of the parameters listed above.
2.2.5.4 Guidance
Additional information on the modeling of I/M program
benefits in MOBILE4 is provided in Appendix 2A. For those cases
where the emission reduction credit matrices included with MOBILE4
are inappropriate for the I/M program being modeled, contact the
Office of Mobile Sources (Technical Support Staff, 313/668-4367 or
FTS 374-8367) to obtain the required matrices.
2.2.6 ANTI-TAMPERING PROGRAMS
2.2.6.1 Description
Some areas of the country have implemented anti-tampering
programs (ATPs) to reduce the frequency and resulting emission
impact of emission control tampering (e.g., misfueling,
disablement or removal of catalytic converters). MOBILE4 allows
the user to include the effects of such a program on the
calculated emission factors.
2.2.6.2 Options
You can choose to model the effects of an ATP on the emission
factors (ATPFLG = 2), or to assume that no ATP is in effect
(ATPFLG = 1). The information required of the user if ATPFLG = 2
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is discussed below. MOBILE4 contains a subroutine that will
generate the applicable emission factor credit matrices based on
the information that you provide on the characteristics of the
ATP. This is significantly different from MOBILES, which required
that the emission factor credit matrices be supplied as part of
the input data.
2.2.6.3 Required Information
The following must be specified by the user in order to have
MOBILE4 model the effects of an ATP, in the order shown:
o Start year (calendar year in which the program begins)
o First (earliest) and last (most recent) model years of
vehicles subject to the program
o Whether or not each of four possible vehicle types
(LDGV, LDGT1, LDGT2, HDGV) are covered by the program
o Program type (centralized or decentralized)
o Frequency of inspection (annual or biennial)
o Compliance rate (percent)
o Inspections performed (air system, catalyst, fuel inlet
restrictor, tailpipe lead deposit test, EGR system,
evaporative system, PCV, gas cap)
The format of this record is:
3(12,IX),411,IX,211,IX,F4.0,IX,811.
Table 2.2-3 summarizes the ATP descriptive input record
required if ATPFLG = 2, including the variable names, codes, and
allowable values for each field of the record. See Appendix 2A of
this chapter for more detailed discussion of each of the
parameters listed above.
2.2.6.4 Guidance
Additional information on the modeling of ATP program
benefits in MOBILE4 is provided in Appendix 2A. Further guidance
on developing the information required to model the emissions
impact of an ATP can be obtained by contacting the Office of
Mobile Sources (Technical Support Staff, 313/668-4367 or FTS
382-8367).
2.2.7 REFUELING EMISSIONS
2.2.7.1 Description
The refueling of gasoline-fueled vehicles results in the
displacement of fuel vapor from the vehicle fuel tank to the
atmosphere. These "refueling emissions" have not been accounted
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for in previous versions of the emission factor model. There are
two basic approaches to the control of vehicle refueling
emissions, generally referred to as "Stage II" (at the pump) and
"onboard" (on the vehicle) vapor recovery systems (VRS). MOBILE4
has the ability to model refueling emissions based on uncontrolled
levels (i.e., assuming no requirements for Stage II or onboard VRS
systems), as well as assuming implementation of either or both of
the major types of VRS.
2.2.7.2 Options
There are five approaches available in MOBILE4 for the
modeling of vehicle refueling emissions, depending on the value
assigned to RLFLAG:
Value Action
1 Model uncontrolled refueling emissions for all
gasoline-fueled vehicle types.
2 Model refueling emissions assuming a Stage II VRS
requirement.
3 Model refueling emissions assuming an onboard VRS
requirement.
4 Model refueling emissions assuming both Stage II
and onboard VRS requirements.
5 Account for refueling emissions elsewhere in the
inventory; no refueling emission factors calculated
by MOBILE4.
There are no additional input requirements for the first or
last approaches. If you wish to include the effects of either or
both VRS requirements on refueling emissions, you must supply
certain information to be assumed about the program.
2.2.7.3 Refueling Emissions in MOBILE4
The uncontrolled refueling emission factors in MOBILE4 are
based on vehicle test results which were used to develop a
regression equation expressing refueling emissions as a function
of fuel RVP, temperature of dispensed fuel, and difference in
temperatures of dispensed and residual tank fuel. The use of
nationwide summertime average values for these parameters yields
refueling EFs in terms of grams of vapor emitted per gallon of
fuel dispensed (g/gal). Combining this with vehicle fuel economy
data (mi/gal) yields refueling emission factors in grams per mile
(g/mi).
If you wish to model the effect of a Stage II VRS requirement
on these emissions, its in-use control efficiencies (for LDGVs and
LDGTs, and for HDGVs) must be entered as input. There are no
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national average values for Stage II efficiency in MOBILE4 . In
modeling an an onboard VRS requirement, MOBILE4 assumes a
96 percent reduction in refueling emissions from onboard-equipped
vehicles.
2.2.7.4 Recfuired Information
To model the effect of a Stage II VRS requirement, you must
provide four inputs: the start year (calendar year in which the
requirement takes effect), the phase-in period (number of years
for Stage II VRS installation to be completed) , and the system
efficiency (in percent) at controlling refueling emissions from
light -duty vehicles and trucks, and from heavy-duty vehicles.
Modeling the effect of an onboard VRS requirement requires
the user to provide only the starting model year and which of the
four possible vehicle types (LDGV, LDGT1, LDGT2, HDGV) are subject
to the requirement. The effects of the EPA reproposal for a
national onboard VRS requirement, due to be published soon, can be
modeled by verifying the specifics of the program with EPA (see
section 2.2.7.5) .
All of the above must be supplied if both VRS requirements
are assumed.
The format of the Stage II VRS descriptive record is:
The format of the onboard VRS descriptive record is:
12, IX, 411.
If both records are to be supplied, the Stage II descriptive
record precedes the onboard descriptive record. Table 2.2-4
summarizes both of these possible records, including the variable
names, codes, and allowable values for each field.
2.2.7.5 Guidance
The overall effectiveness of Stage II VRS at controlling
refueling emissions depends on a number of factors, including the
baseline efficiency of the system used, the portion of total area
gasoline consumption handled by service stations exempt from
Stage II requirements, and the frequency and stringency of
enforcement programs. In general, the effectiveness of Stage II
VRS at controlling refueling emissions will be greater for light-
duty vehicles and trucks than for heavy-duty vehicles, since HDGVs
are more likely to be refueled at service stations (or other fuel
dispensing locations, such as private refueling depots) that will
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be exempted from Stage II requirements. For assistance in
developing such information, contact EPA's Office of Air Quality
Planning and Standards (919/541-5397 or FTS 629-5397).
Since any onboard requirement would be a national control
program, the only issues are what model year the program will be
implemented and whether or not all gasoline-fueled vehicles will
be covered. Contact the Office of Mobile Sources (Standards
Development and Support Branch, 313/668-4423 or FTS 374-4423) to
determine this.
If the user chooses not to model refueling emissions using
MOBILE4 (RLFLAG = 5), then these emissions must be accounted for
in the stationary source portion of the inventory in the
development of the base and projected emission inventories. The
effects of an onboard VRS system requirement cannot be modeled if
this approach is taken. EPA recommends the use of MOBILE4 to
model refueling emissions for SIP-related inventory development
and projections.
2.2.8 LOCAL AREA PARAMETER RECORD
2.2.8.1 Description
The local area parameter (LAP) record consists of seven
locality-specific input variables, and must be included at least
once in every MOBILE4 run.
2.2.8.2 Options
You can choose to use one LAP for all scenarios (LOCFLG = 2)
or a different LAP for each scenario (LOCFLG = 1). The same LAP
generally should be used for all scenarios (e.g., for different
evaluation years) for the same locality, with the exception of the
scenario name (see section 2.2.9).
2.2.8.3 Content of the LAP
The following variables comprise the LAP record:
1)
2)
3)
4)
Scenario name
ASTM volatility class
Minimum daily temperature
Maximum daily temperature
5) Base RVP
6) In-use RVP
7) In-use RVP start year
Each of these variables is discussed in sections 2.2.9
through 2.2.13, below. Table 2.2-5 summarizes the LAP record,
including the content, variable name, codes, and allowable values
for each field of the record.
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2.2.9 SCENARIO NAME
2.2.9.1 Description
You are provided with 16 character spaces for entering an
identifying label for each scenario within a run. This is simply
echoed as part of the output.
2.2.9.2 Guidance
If no scenario name is desired, a blank record must be
entered here. This record is typically used to define the most
important characteristics distinguishing the scenario from others
within the same MOBILE4 run (e.g., calendar year of evaluation,
inclusion of I/M program).
2.2.10 ASTM VOLATILITY CLASS
2.2.10.1 Description
The nation is divided by the American Society for Testing and
Materials (ASTM) into five volatility classes, designated by a
letter (A-E), for each month of the year. A recommended maximum
fuel volatility (Reid vapor pressure, or RVP) is associated with
each letter. Compliance with ASTM volatility limits by the
petroleum refining and supply industries is voluntary, but these
designations are a reasonably accurate estimation of the average
volatility of gasoline in a given area during a given month.
2.2.10.2 Options
The user must input a value for the ASTM volatility 'class in
the base year. This can be any valid ASTM volatility class (A, B,
C, D, or E). However, there are specific values assigned by ASTM
for each state, or part of state, for each month of the year.
2.2.10.3 Use in MOBILE4
MOBILE4 maps the ASTM volatility class to the corresponding
suggested RVP limit, in psi (A —> 9.0, B —> 10.5, C —> 11.5,
D —> 13.5, E —> 15.0). This is used to adjust the uncontrolled
refueling emission factors contained in MOBILE4 Block Data for
fuel volatility other than ASTM Class C (i.e., other than 11.5
psi). It is also used in the modeling of the effects of fuel
volatility limiting regulations, which are keyed to the volatility
of fuel in ASTM Class C areas with proportional RVP reductions
required in other ASTM areas.
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2.2.10.4 Required Information
Specification of ASTM volatility class in the form of one of
the five letters A/B/C/D/E.
2.2.10.5 Guidance
Fuel volatility primarily affects evaporative HC emissions,
which in turn are primarily an ozone season (i.e., summer)
concern. Thus if you are modeling summer HC emissions, the July
ASTM class for the area of interest should be used. Further
information on determining the appropriate ASTM volatility class
for use in MOBILE4 is provided in Appendix 2B.
2.2.11 MINIMUM and MAXIMUM DAILY TEMPERATURE
2.2.11.1 Description
The minimum and maximum daily temperatures are used in
MOBILE4 in the calculation of the diurnal portion of evaporative
HC emissions. The temperatures used in calculating the
temperature corrections to exhaust HC, CO, and NOx emissions, the
hot soak portion of evaporative emissions, and the running loss HC
emissions will be calculated by MOBILE4 based on the minimum and
maximum temperatures input here if TEMFLG = 1, and is not the same
as the input ambient temperature (section 2.3.4).
2.2.11.2 Options
The user must input values for the minimum and maximum
ambient temperatures. The minimum temperature must be between 0°F
and 100°F (-18° to 38°C), and the maximum temperature must be
between 10°F and 120°F (-12° to 49°C) inclusive. The maximum
temperature must be greater than or equal to the minimum
temperature.
2.2.11.3 Use in MOBILE4
MOBILE4 uses the temperature limits of the evaporative
portion of the Federal Test Procedure (FTP) [minimum 60°F (16°C),
maximum 84°F (29°C)] to estimate basic diurnal emission rates.
Diurnal emissions in MOBILE4 are adjusted for the minimum and
maximum temperatures provided as input through the use of the
uncontrolled diurnal index (UDI)*, which expresses diurnal
* For further discussion of the UDI and its use in estimating the
diurnal portion of evaporative emissions, see "Draft Regulatory
Impact Analysis for Control of Gasoline Volatility and Evaporative
Hydrocarbon Emissions from New Motor Vehicles," U.S. EPA, OAR,
QMS, July 1987; pp. 2-54 to 2-71.
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emissions for a given range of temperature as a multiple of FTP
diurnal emission rates. This is done whether TEMFLG = 1 or 2.
The basic exhaust emission rates for HC, CO, and NOx are
based on temperature of 75°F. MOBILE4 calculates an average
temperature for each pollutant, representing average emissions
over the course of the day, based on the input minimum and maximum
daily temperatures, and adjusts the exhaust emission factors for
temperature effects accordingly, if TEMFLG = 1. Hot soak
emissions ' at FTP conditions are based on a temperature of 82°F
(28°C). MOBILE4 calculates a temperature for the hot soak
emissions based on the minimum and maximum temperatures input here
if TEMFLG = 1, and adjusts the basic hot soak emission rates for
temperature effects accordingly. Running loss HC emissions are
also dependent on temperature. As for exhaust and hot soak
emissions, MOBILE4 calculates an appropriate average temperature
for use in correcting running loss emissions, weighted to account
for differing emission levels at different temperatures in the
range of the minimum and maximum daily temperatures, if TEMFLG = 1.
If TEMFLG = 2, the user-supplied input value of ambient
temperature (see section 2.3.4) is used to determine temperature
corrections for exhaust HC, CO, and NOx emissions, hot soak
evaporative emissions, and running loss emissions. The use of
TEMFLG = 2 is not recommended unless the modeling of a very short
time period , such as an hour, is being performed. For modeling
of entire days, TEMFLG = 1 is recommended, and will provide more
accurate temperature corrections to the emission factors.
2.2.11.4 Recfuired Information
Minimum and maximum daily temperatures (°F).
2.2.11.5 Guidance
The temperatures to be used here depend on the intended
application of the results. Restrictions on these temperatures
are: the maximum temperature must be greater than or equal to the
minimum temperature, and the ambient temperature (used to adjust
exhaust, hot soak, and running loss emission factors if TEMFLG = 1,
and input as part of the Scenario section) should be between the
minimum and maximum.
If the input daily maximum temperature or the calculated hot
soak or running loss temperature is <. 40°F, or if the input daily
minimum temperature is <_ 25°F, evaporative emissions (including
running loss emissions) are not calculated. EPA does not have
sufficient data to estimate evaporative emissions at low
temperatures, and there is reason to believe that such emissions
approach zero when temperatures are sufficiently low. The MOBILE4
output will include a comment message noting that evaporative
emission factors are not calculated if any of these conditions
occur.
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The model used in MOBILE4 to calculate diurnal emissions may
not be accurate when very large diurnal temperature ranges are
used. Thus, if the diurnal temperature range (daily maximum minus
daily minimum) is > 40 F°, a warning message is printed noting
that the diurnal evaporative emission factor has been calculated
but may be inaccurate.
Crankcase emissions are always included in the evaporative
emission factors. If evaporative emissions are not calculated for
any of the reasons noted above, crankcase emissions are still
calculated and output (as the only contributor to evaporative
emissions), since these emissions are dependent on engine
operating temperatures rather than ambient temperatures.
Finally, if the calculated exhaust emission correction
temperature is <_ 40°F, exhaust emission factors are not corrected
for the effects of fuel volatility (RVP), for similar reasons.
2.2.12 BASE RVP
2.2.12.1 Description
Evaporative (and to a lesser extent exhaust) emissions vary
with fuel volatility. EPA's new vehicle certification program and
much of its emission factor testing use gasoline with a volatility
(RVP) of 9.0 psi. However, in recent years much of the country
has been supplied with gasoline of higher (in some cases,
considerably higher) volatility. MOBILE4 adjusts the emission
factors to account for the effects of fuel volatility.
The value to be used for base RVP is the in-use average RVP
of gasoline in the area to be modeled that prevails in the base
year, and is expected to prevail up to the in-use volatility
control start year. (The major function of base and in-use RVP
values in MOBILE4 is to allow the user to define a step change in
fuel volatility at a specific calendar year; see section 2.2.13.)
2.2.12.2 Options
The value used for base RVP can be anywhere between 7.0 psi
and 15.2 psi inclusive. However, for accurate and meaningful
results, the guidance provided below should be followed.
2.2.12.3 Use in MOBILE4
The base RVP is used in MOBILE4, for calendar years of
evaluation prior to the in-use start year, to account for the
effects of fuel volatility on emissions. Thus, the use of the
appropriate value of RVP allows the construction of more accurate
emission factors and a more accurate base inventory. If the
calendar year of evaluation is after the specified in-use start
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year, then the base RVP input value is ignored (in the sense that
it will not have an impact on the emission factors for the
evaluation year).
2.2.12.4 Recruired Information
A value of RVP (in psi) representing the current prevailing
average fuel volatility for the geographic area of interest, in
the absence of any requirements for volatility control.
2.2.12.5 Guidance
As with the temperature inputs discussed above, the intended
use of the MOBILE4 run determines the season for which in-use RVP
should be determined. For ozone-related (summer season) modeling,
use the summer (July) RVP. Alternatively, if modeling of emission
factors is being performed on a month-by-month basis, the value of
base RVP appropriate to each of the specific months being modeled
should be used.
The impact of fuel volatility on emissions is much lower at
colder temperatures. (In MOBILE4, no correction to exhaust
emissions to account for the effects of RVP is applied if the
calculated (TEMFLG = 1) or input (TEMFLG = 2) temperature
applicable to exhaust emissions is <^0°F.) For CO modeling, the
base RVP for the season of interest (which will depend on when and
at what temperatures most CO violations occurred) should be used.
Again, if modeling is being performed on a month-by-month basis,
values of RVP appropriate to each month for which emission factors
are being modeled should be used. Further guidance on the
determination of the appropriate value to use as input for base
RVP is provided in Appendix 2B.
2.2.13 IN-USE RVP and IN-USE START YEAR
2.2.13.1 Description
EPA has proposed that summer fuel RVP be limited to 9.0 psi
in ASTM Class C areas, with corresponding proportional reductions
in summer fuel RVP for ASTM Class A and B areas.* MOBILE4
provides the ability to model the effects of an RVP control
program through specification of the in-use RVP limit and the year
in which the requirement is effective.
2.2.13.2 Options
The user must input values for the in-use RVP and in-use
start year. The value of in-use RVP can be between 7.0 and 15.2
psi inclusive. If you wish to include in the modeling the effects
* Federal Register, Vol. 52 No. 160, August 19, 1987; pp. 31274.
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of an in-use fuel volatility control program, then appropriate
values for in-use RVP and in-use start year should be provided.
The earliest allowed in-use start year is 1989. Thus the effects
of local (state, regional) fuel volatility control programs, which
may be more stringent and/or take effect sooner than Federal
controls, can be modeled. It is also possible to assume no in-use
volatility control program (see section 2.2.13.4).
2.2.13.3 Repaired Information
The control RVP level to be assumed (psi) and the calendar
year in which the control program is first effective.
To model the effects of the Federal volatility control
program proposed by EPA, in which volatility would be limited in
the summer months (May through September) in ASTM Class C areas
with proportional limits required in ASTM Class A and B areas,
contact EPA's Office of Mobile Sources (Standards Development and
Support Branch, 313/668-4423 or FTS 374-8423) to determine the
appropriate input values.
2.2.13.4 Guidance
If no fuel volatility control program is to be assumed, then
the value of base RVP should be used as the value of in-use RVP as
well. In this case, with no change in RVP, the start year of RVP
control should be set to CY 2020 (IUSESY = 20). To model the
effect of a summer fuel volatility control program, you should use
the proposed summer RVP limit as the value of in-use RVP, and the
year in which the program is projected to take effect as the value
of in-use start year.
This concludes the One-time data section.
2.3 SCENARIO SECTION
The Scenario data follow the One-time data in the MOBILE4
input stream, and are used to assign values to those variables
that specifically define each of the scenarios to be evaluated.
It consists of one to four records, depending on the values set in
the Control section.
The user can calculate emissions for one or more scenarios.
Each scenario is associated with one group of Scenario section
records. The program terminates execution upon detecting an
end-of-file condition.
The first record, consisting of those variables discussed in
sections 2.3.1 through 2.3.5, must be included for every scenario
of every MOBILE4 run. The second possible record, required only
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if LOCFLG = 1, consists of local area parameters to be applied for
this scenario only (see sections 2.1.13, 2.2.8 through 2.2.13).
The third possible record, required only if VMFLAG = 3, consists
of the VMT mix to be applied for this scenario only (see sections
2.1.6, 2.2.2). The fourth possible record, required only if
ALHFLG = 2 or 3, consists of either six or ten additional input
values used to correct certain exhaust emission factors (see
sections 2.1.10 and 2.3.8).
Table 2.3-1 summarizes the Scenario section input record(s),
including the variable names, codes, and allowable values for each
field.
2.3.1 REG I ON
2.3.1.1 Description
The first specification required in the first record of the
Scenario data section is the region for which emission factors are
to be calculated.
2.3.1.2 Options
MOBILE4 provides two options for region: low-altitude and
high-altitude. Low-altitude emission factors are based on
conditions representative of approximately 500 feet above mean sea
level (+500 ft MSL), and high-altitude factors are based on
conditions representative of approximately +5500 ft MSL. MOBILE4,
like MOBILES, does not calculate California emission factors.
2.3.1.3 Use in MOBILE4
The region selected determines whether the MOBILE4 emission
factor calculations will be based on low-altitude or high-altitude
basic emission rates.
2.3.1.4 Repaired Information
You must enter a value of either 1 (low-altitude) or 2
(high-altitude) for the region.
2.3.1.5 Guidance
For the majority of MOBILE4 applications, low-altitude is the
appropriate choice. For those areas designated as high- altitude
by EPA for mobile source regulatory purposes, generally those
counties that lie "substantially" above +4000 ft MSL,
high-altitude should be selected. A list of those counties EPA
has designated as high-altitude appears in §86.088-30, paragraphs
(a)(5) (ii) and (iv), Code of Federal Regulations.
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2.3.2 CALENDAR YEAR
2.3.2.1 Description
The value used for calendar year in MOBILE4 defines the year
for which emission factors are to be calculated (as of January l).
2.3.2.2 Options
MOBILE4 has the ability to model emission factors for the
years 1960 through 2020 inclusive.
2.3.2.3 Required Information
You must enter a value for the last 2 digits of the calendar
year of evaluation (range 60-99 and 00-20).
2.3.3 SPEED
2.3.3.1 Description
Emission factors vary considerably with the average speed
assumed. The value(s) input for speed in MOBILE4 will have a
significant impact on the resulting emission factors. In general,
HC and CO emissions are at a minimum at the average speed of the
Federal Test Procedure (FTP) used for new vehicle certification,
or 19.6 mph, with emissions increasing as average speeds move
further from that value (either higher or lower). NOx emissions
are generally higher than FTP rates at speeds under 19.6 mph, and
slightly lower than FTP rates at speeds greater than 19.6 mph.
2.3.3.2 Options
You have the option of using one average speed for all
vehicles (SPDFLG = 1) or of using eight average speeds, one for
each vehicle type (SPDFLG = 2). MOBILE4 will calculate - emission
factors for average speeds of 2.5 to 55.0 mph, in increments of
0.1 mph. If a speed below 2.5 mph is input, a warning message
will be issued by MOBILE4 and 2.5 mph will be used in the
calculations. Note that the minimum speed of 2.5 mph represents a
reduction from the 5.0 mph minimum speed that could be used in
MOBILES.
Similarly, if a speed above 55 mph is input, a warning
message will be issued and 55.0 mph will be used in the
calculations. Although the speed limit has been increased to
65 mph on certain portions of limited access highway in some
states, EPA does not have data adequate for the characterization
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of emissions at higher speeds and does not believe that the
extrapolation of the speed correction factor equations to such
speeds should be considered reliable. Further, areas with a legal
speed limit of 65 mph are generally rural (outside of urban areas
with populations of 50,000 or more). Thus, 55.0 mph continues to
be the maximum speed for which MOBILE4 will calculate emission
factors.
2.3.3.3 Use of Average Speed in MOBILE4
The data base on which all emission factor calculations are
based is developed from vehicle test results at based on FTP
conditions, including the average speed of 19.6 mph. MOBILE4
adjusts the emission factors for speeds other than 19.6 mph
(20 mph for HDGVs and HDDVs) through the use of speed correction
factors.
2.3.3.4 Required Information
You must supply either a single value which is assumed to
apply to all vehicles (if SPDFLG = 1), or eight values (one for
each regulated vehicle class) in the following order: LDGV,
LDGT1, LDGT2, HDGV, LDDV, LDDT, HDDV, MC (if SPDFLG = 2).
2.3.3.5 Guidance
The FTP driving cycle is intended to be representative of
driving conditions typical of a standard commute in an urban
area. Thus the use of 19.6 mph as the average speed applicable to
all vehicle types is appropriate for many modeling situations
intended to represent traffic in urban areas as a whole. The
average speed of the transient test cycle used for heavy-duty
engine certification is 20 mph, which is representative* of urban
driving overall but not of commuting trips. Use of 19.6 mph as
the average speed for all vehicles therefore will lead to a small
speed correction being applied to HDGV and HDDV emission factors.
For some applications of MOBILE4, you might assume a single
value other than 19.6 mph. For example, to model emission factors
typical of a stretch of limited access highway, the use of 55 mph
for all vehicle types would be appropriate.
The prediction of average speeds in the future is difficult,
and may be a critical factor in some areas' ability to project
compliance with SIP commitments and air guality standards. EPA
may provide additional guidance in the final SIP calls for control
strategies and attainment demonstrations.
If you need to run MOBILE4 using speed(s) representative of
certain areas (e.g., subsets of urban areas, specific highway
links) or of certain times of day, there are often speed data
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available from local, regional, or state transportation planning
agencies. A discussion of how average speeds can be estimated
from available data sources is presented in "Procedures for
Emission Inventory Preparation, Volume IV: Mobile Sources,"
(revised), EPA-450/4-81-026d.
2.3.4 AMBIENT TEMPERATURE
2.3.4.1 Description
Refer also to sections 1.1.4, 2.1.14, and 2.2.11.
Emissions vary considerably with ambient temperature. The
value of temperature used to apply the temperature correction
factors for exhaust emissions, hot soak evaporative emissions, and
running loss emissions will have a significant impact on the
resulting emission factors.
If TEMFLG = 1, the temperature used to adjust the exhaust
emission factors for all three pollutants, the hot soak component
of evaporative emissions, and running loss emission factors will
be calculated by MOBILE4 on the basis of the input minimum and
maximum daily temperatures. The ambient temperature specified
here will not be used.
If TEMFLG = 2, the value of ambient temperature specified
here will be used as the basis of the temperature correction
factors for all exhaust emissions, hot soak evaporative emissions,
and running loss emissions. The input values for minimum and
maximum daily temperatures will still be used in calculating the
diurnal component of evaporative emissions. The use of TEMFLG = 2
causes the input value of ambient temperature to be used to
correct the exhaust emission factors in the same way as in MOBILES.
If the specified ambient temperature is inconsistent with the
minimum and maximum daily temperatures (e.g., 20°F ambient with
60°-84°F minimum and maximum), an error message will result and
processing of the current scenario will be aborted.
2.3.4.2 Options
The ambient temperature specified can range from 0°F (-18°C)
to 110°F (43°C). If a temperature less than 0°F is input, a
warning message will be issued, and 0°F will be used in the
calculations if TEMFLG = 2. Similarly, if a temperature greater
than 110°F is input, a warning is issued, and 110°F is used in the
calculations if TEMFLG = 2.
2.3.4.3 Use of Ambient Temperature in MOBILE4
The basic emission rates that underlie the emission factor
calculations are developed from emission data from vehicles tested
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at FTP conditions, with an ambient temperature of 75°F (24°C).
MOBILE4 uses temperature correction factors to correct exhaust
emission factors to temperatures other than 75°F. If TEMFLG = 2,
the value input here for ambient temperature is used to make these
corrections.
2.3.4.4 Recruired Information
A value of ambient temperature in degrees Fahrenheit (°F).
2.3.4.5 Guidance
As with many of the other input parameters, the value used
for AMBT depends in large part on the purpose for which MOBILE4 is
being run. Some suggestions are offered below. Additional
information and guidance on the determination of the appropriate
ambient temperature is provided in Appendix 2C.
The ambient temperature logically must be between the minimum
and maximum temperatures. This is particularly important when HC
emission factors are being modeled, since minimum and maximum
temperatures are used in the evaporative emission component of
those calculations (section 2.2.11), and the evaporative and
exhaust components of the emission factor should be estimated on a
consistent basis. Modeling of CO emission factors is more likely
to focus on times with cooler temperatures, when most violations
of the National Ambient Air Quality Standard (NAAQS) for CO occur.
2.3.5 OPERATING MODES (PCCN, PCHC, PCCC)
2.3.5.1 Description
One important determinant of emissions performance is the
mode of operation. EPA's emission factors are based on testing
over the FTP cycle, which is divided into three segments (referred
to as "bags"), each with differing associated emissions
performance. The bags correspond to operating modes:
Bag Operating Mode
1 Cold start
2 Stabilized
3 Hot start
Emission data from each of these bags reflect the fact that
emissions generally are highest when a vehicle is in cold-start
mode: the vehicle, engine, and emission control eguipment
(particularly the catalytic converter) are all at ambient
temperature and thus not performing at optimum levels. Emissions
are generally somewhat lower in hot start mode, when the vehicle
is not yet completely warmed up but was not sitting idle for
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sufficient time to have cooled completely to ambient temperatures.
Finally, emissions generally are lowest when the vehicle is
operating in stabilized mode, and has been in continuous operation
long enough for all systems to have attained relatively stable,
fully "warmed-up" operating temperatures.
The three variables PCCN, PCHC, PCCC are sufficient to
completely define the percent VMT accumulated in each of the three
operating modes by vehicles in each of two basic emission control
configurations, non-catalyst and catalyst-equipped. Thus the
input of values for percent VMT accumulated in hot start mode by
non-catalyst vehicles, or in stabilized mode by non-catalyst or
catalyst-equipped vehicles, is not required as input. MOBILE4
calculates these quantities from the three values entered.
The definitions of the three variables and how together they
define six vehicle type/operating mode combinations are shown
below:
Vehicle Type Operating Mode Defined in MOBILE4 as:
Non-catalyst
Catalyst
Catalyst
Catalyst
Cold-start
Hot-start
Cold-start
Stabilized
Non-catalyst Stabilized
Non-catalyst Hot-start
PCCN
PCHC
PCCC
1.0 - PCCC - PCHC
1.0 - PCCC - PCHC
(assumed equal to the
stabilized VMT fraction for
catalyst-equipped vehicles)
PCCC - PCCN + PCHC
The user should not expect the sum of PCCN + PCHC + PCCC to
be 100 percent. While it is true that (percent VMT in cold-start
mode) + (percent VMT in hot-start mode) + (percent VMT in hot
stabilized mode) always equals 100 percent, for both catalyst-
equipped and non-catalyst vehicles separately, the variables PCCN,
PCHC, and PCCC are not equivalent to these variables.
The values of PCHC, PCCC, and PCCN are used in the
calculation of the bag-dependent correction factors (such as
temperature and volatility) for LDV, LDT, and MC emission
factors. It is assumed that all diesel vehicles and all
motorcycles are always non-catalyst.
EPA historically has defined cold starts to be any start that
occurs at least four hours after the end of the preceding trip for
non-catalyst vehicles and at least one hour after the end of the
preceding trip for catalyst-equipped vehicles. Hot starts are
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those starts that occur less than four hours after the end of the
preceding trip for non-catalyst vehicles and less than one hour
after the end of the preceding trip for catalyst- equipped
vehicles. The shorter time interval associated with the cold/hot
start definition for catalyst-equipped vehicles reflects the fact
that catalytic converters do not operate at intended efficiency
until they are fully warmed up (to operating temperatures in the
600°F (316°C) range); thus catalyst-equipped vehicles reflect
"cold-start" emissions performance after a much shorter off time
than do non-catalyst vehicles, which do not depend on attainment
of such high temperatures for stabilization of emissions
performance.
2.3.5.2 Options
The three specified values must all be expressed as
percentages (not fractions). The sum of PCHC + PCCC must be less
than 100 percent (if PCCC + PCHC = 100%, for example, the implicit
statement is that catalyst-equipped vehicles accumulate no VMT in
stabilized mode). The value of PCCN logically should be less than
that of PCCC, for the reasons discussed above.
2.3.5.3 MOBILE4 Standard (FTP) Operating Mode Fractions
The values of the three variables corresponding to the
conditions of the FTP cycle are:
PCCN 20.6 %
PCHC 27.3 %
PCCC 20.6 %
These values reflect the same assumptions and conditions that are
reflected in other aspects of the Federal Test Procedure.
2.3.5.4 Repaired Information
Three percentage values, reflecting the percentage of VMT
(not the percentage of vehicles) accumulated by non-catalyst
vehicles in cold-start mode (PCCN), by catalyst-equipped vehicles
in hot-start mode (PCHC), and by catalyst-equipped vehicles in
cold-start mode (PCCC).
2.3.5.5 Guidance
In the absence of supporting data for values other than those
listed above, EPA believes that the values reflecting FTP
conditions are appropriate in many cases. This is particularly
true when the emission factors being modeled are intended to
represent a broad geographic area (Metropolitan Statistical Area,
entire state) and/or a wide time period (days, months). When the
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modeling is intended to represent highly localized conditions
(specific highway links) or very limited periods of time (as
single hours), it may be possible to develop more representative
values for these variables. Areas known to have average trip
lengths significantly shorter or longer than 7.5 miles may also
merit the use of alternate values.
Thus for SIP-related modeling, EPA will accept the use of the
FTP operating mode values except for small scale scenarios where
their use would clearly be inappropriate. EPA will not accept
SIP-related modeling that includes different operating mode
fractions for the base and projection years without adequate
quantitative written justification.
There are several ways of approximating the percentage of VMT
accumulated in each mode for each type of vehicle, although highly
accurate determinations are not readily obtainable. Guidance on
three possible methods for determining the cold- start/hot-start
VMT fractions for non-catalyst and catalyst- equipped vehicles,
including references to generally available data sources, appears
in Chapter 8 of the report "Techniques for Estimating MOBILE2
Variables."
2.3.6 LOCAL AREA PARAMETER RECORD
The local area parameter (LAP) record was discussed in
sections 2.2.8 through 2.2.13, and is summarized in Table 2.2-5.
It must appear in the Scenario data section if a different LAP
record is to be applied to each scenario (LOCFLG = 1), and must
appear in the One-time data section if the same LAP record is to
be applied for all scenarios (LOCFLG = 2). The information
provided in sections 2.2.8 through 2.2.13 is applicable in either
case. This record must be supplied, in either the One-time data
section or the Scenario data section, for every MOBILE4 run.
2.3.7 VEHICLE MILES TRAVELLED MIX by vehicle type
The VMT mix was discussed in section 2.2.2. This record must
appear in the Scenario data section if different VMT mixes are to
be applied to each scenario (VMFLAG = 2), and must appear in the
One-time data section if the same VMT mix is to be applied to all
scenarios (VMFLAG = 3). The information provided in section 2.2.2
is applicable in either case. This record is not required if the
MOBILE4 VMT mix is to be used (VMFLAG =1).
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2.3.8 Additional Correction Factors for Light-Duty
Gasoline-Fueled Vehicle Types
2.3.8.1 General Description
MOBILE4 provides the capability of applying four additional
correction factors to the exhaust emission factors for LDGVs,
LDGTls, and LDGT2s. These factors are used to represent unique
conditions not typically assumed in MOBILE4 runs, which is why
they are segregated from other correction factors (such as speed
and temperature).
These factors allow for exhaust emission factors only to be
adjusted to account for the emissions impact of air conditioning
(A/C) usage, extra loading, and trailer towing. There is also a
humidity correction factor, which applies only to exhaust NOx
emissions and is also applied to motorcycles.
2.3.8.2 Options
Depending on the value assigned to the ALHFLG flag
controlling the application of these additional correction
factors, six or ten input values may be required.
When ALHFLG = 2, six values are required:
1) One A/C usage fraction (for all LDGVs and LDGTs)
2-4) Three extra load usage fractions (one each for LDGVs,
LDGTls, and LDGT2s)
5) One trailer towing fraction (for all LDGVs and LDGTs)
6) One humidity level (for all LDGVs and LDGTs plus
motorcycles)
When ALHFLG = 3, ten values are required:
1) One A/C usage fraction (for all LDGVs and LDGTs)
2-4) Three extra load usage fractions (one each for LDGVs,
LDGTls, and LDGT2s)
5-7) Three trailer towing fractions (one each for LDGVs,
LDGTls, and LDGT2s)
8) One humidity level (for all LDGVs and LDGTs plus
motorcycles)
9-10) Dry bulb and wet bulb temperatures (used to calculate
an A/C usage fraction for LDGVs and LDGTs).
Each of these five types of input (A/C, extra load, trailer
towing, humidity, and temperature) are discussed below.
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2.3.8.3 A/C Usage Fraction (AC)
2.3.8.3.1 Description
If you wish to include the effect on the exhaust emission
factors of A/C usage, enter a value representing the fraction of
A/C-eguipped vehicles assumed to actually be operating with their
air conditioners running.
2.3.8.3.2 Options
This fractional value must be between zero and one
(0.0 <_ AC £ 1.0). If the value entered is zero, no correction
will be applied (i.e., the correction factor will be 1.0).
In the six value option (ALHFLG = 2), the value of AC input
here will be used to determine the correction factor.
In the ten value option (ALHFLG = 3), the A/C usage fraction
will be calculated on the basis of the dry bulb and wet bulb
temperatures (see section 2.3.8.7). In this case any value can be
entered for AC, subject to the constraint that 0.0 <_ AC <^ 1.0, but
it will be ignored by MOBILE4 in favor of the calculated usage
fraction.
2.3.8.4 Extra Load Usage Fractions [XLOADQ)]
2.3.8.4.1 Description
These values are used to model the exhaust emissions impact
of vehicles carrying an extra 500 Ib (227 kg) load. If,you wish
to include this effect, three fractional values are entered (one
each for LDGVs, LDGTls, and LDGT2s), representing the fraction of
all vehicles of the given type carrying such an extra load.
2.3.8.4.2 Options
These values must all lie between zero and one
(0.0 <_ XLOAD(i) _£ 1.0). If the value entered is zero, no
correction for the effects of extra load is applied.
2.3.8.5 Trailer Towing Usage Fraction [TRAILR or TRAILRQ)]
2.3.8.5.1 Description
These values are used to model the impact on exhaust
emissions of vehicles towing trailers. If you wish to include
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this effect in your modeling, one or three fractions are entered
representing the fraction of vehicles of a given type that are to
be assumed to be towing trailers.
2.3.8.5.2 Options
Any value for this fraction must lie between zero and one
(0.0 <_ TRAILR(i) <_ 1.0). If the value entered is zero, no
correction for the effect of trailer towing is applied.
In the six value option (ALHFLG = 2), one value is entered
and is applied to LDGVs, LDGTls, and LDGT2s.
In the ten value option (ALHFLG = 3), three values are
entered, and one each is applied to LDGVs, LDGTls, and LDGT2s.
2.3.8.6 NOx Humidity Correction (ABSHUM)
2.3.8.6.1 Description
This value is used to correct exhaust NOx emission factors
for absolute humidity. The value entered is the absolute
(specific) humidity, expressed as grains of water per pound of dry
air.
2.3.8.6.2 Options
The value entered for absolute humidity must lie between 20
and 140 (20. <_ ABSHUM <_ 140.). If the value entered is 75,
corresponding to the absolute humidity condition of the FTP, then
no correction will be applied.
fr
2.3.8.7 Dry and Wet Bulb Temperatures (DB. WB)
2.3.8.7.1 Description and Use in MOBILE4
MOBILE4 will calculate the fraction of A/C-eguipped vehicles
actually using their air conditioning on the basis of a
"discomfort index," which in turn is calculated from the dry bulb
and wet bulb temperatures.
2.3.8.7.2 Options and Guidance
The values of each of these temperatures must be between 0°
and 110°F (-18° and 43°C), inclusive. In addition, the wet bulb
temperature must be less than or equal to the dry bulb
temperature. If any of these three conditions are not met, an
error message will be issued by MOBILE4.
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These values (in °F) will be used to calculate the A/C usage
fraction on the basis of the discomfort index only if the ten
value option is selected (ALHFLG =3). If used, this calculated
value will override any value read in for AC as part of the input.
2.3.8.8 Guidance
The use of these additional correction factors is rarely
necessary for most users of MOBILE4. It should be noted that the
data underlying these correction factors was developed for
MOBILE2, and have not been updated since that time. (For example,
the air conditioning correction factor is based in part on the
fraction of vehicles that are equipped with air conditioning; this
fraction is substantially higher for the vehicle fleet of the late
1980s than it was for the fleet of the late 1970s, a fact which is
not reflected in MOBILE4).
If you believe that conditions applying to a specific
application of MOBILE4 warrant the use of one or more of the
correction factors described in this section, and desire guidance
beyond that provided above, contact EPA for additional information
(Test and Evaluation Branch, 313/668-4325 or FTS 374-8325).
2.4 SUMMARY OF MOB ILE4 INPUT SEQUENCE
Table 2.4-1 summarizes the input sequence required for a
MOBILE4 run, in the order required by the program. Records listed
in parentheses are optional, and are only required if certain
flags have been assigned specific values in the Control section.
2.5 OBTAINING REFERENCED DOCUMENTS
Two of the reports specifically mentioned in the guidance
subsections of this document, "Techniques for Estimating MOBILE2
Variables" and "Additional Techniques for Estimating MOBILE2
Variables," can be obtained through the National Technical
Information Service (NTIS). These reports were prepared by Energy
and Environmental Analyses, Inc., for EPA under contract (Contract
No. 68-03-2888). The NTIS number is:
Report Title NTIS Number
"Techniques for Estimating MOBILE2
Variables" and "Additional Techniques
for Estimating MOBILE2 Variables"
(both reports come as one order) PB 83 183277
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For price information and to order, contact
National Technical Information Service
U. S. Department of Commerce
5285 Port Royal Road
Springfield, VA 22161
Attention: Sales
Phone: (703) 487-4650
The User's Guides to the earlier emission factor models,
MOBILE2 and MOBILES, are also available thorough NTIS at at the
above address for those who might wish to obtain them:
Title: User's Guide to MOBILE2
NTIS Ref: PB 81 205619
Estimated costs: Paper - $34.95
(as of 1/1/89) Microfiche - $ 5.95
Title: User's Guide to MOBILE3
NTIS Ref: PB 84 213974
Estimated costs: Paper - $34.00
(as of 1/1/89) Microfiche - $ 5.95
The report referenced in section 1.0, "Guidance on
Estimating Motor Vehicle Emission Reductions From the Use of
Alternative Fuels and Fuel Blends," is also available through
NTIS:
Title: Guidance on Estimating Motor
Vehicle Emission Reductions From
the Use of Alternative Fuels and
Fuel Blends
NTIS Ref: PB 88 169594/AS
Estimated cost: Paper - $14.95
(as of 1/1/89)
The report "Procedures for Emission Inventory Preparation,
Volume IV: Mobile Sources," (revised), EPA-450/4-81-026d,
December 1988, should be available to State and local air
quality planning officials by contacting their respective EPA
Regional Offices.
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Table 2.1-1
FLAGS CONTROLLING INPUT TO AND EXECUTION OF MOBILE4
Record Variable
Number Name
Content and Codes
Format
Refer to
Section
PROMPT Flag for prompting of
remaining Control
section data
1 = No prompting, vertical format
2 = Prompting, vertical format
3 = No prompting, horizontal format
4 = Prompting, horizontal format
IOUNEW Values for output units:
(1) Formatted reports unit
(2) Diagnostic messages unit
(3) Prompting messages unit
(Allowable values for each unit
are 1, 2, 3, 6, 7, or 8. The
default value for all three
output units is 6.)
2.1.1
2.1.2
PROJ10
80 characters for title
20A4
2.1.3
TAMFLG Flag for optional input of
tampering rates.
1 = Use MOBILE4 rates
2 = Input alternate rates1
II
2.1.4
SPDFLG Selects speeds for each
vehicle type.
1 = One speed for all
vehicle types2
2 = Eight speeds, one for
each vehicle type2
II
2.1.5
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Table 2.1-1 (continued)
FLAGS CONTROLLING INPUT TO AND EXECUTION OF MOBILE4
Record Variable
Number Name
Content and Codes
Format
Refer to
Section
VMFLAG Selects optional use of
user-supplied VMT mix
among vehicle types.
1 = Use MOBILE4 VMT mix
2 = Input one VMT mix for
each scenario2
3 = Input one VMT mix for
all scenarios1
II
2.1.6
MYMRFG Flag for optional input of
annual mileage accumulation
rates and/or registration
distributions by age.
1 = Use MOBILE4 values
2 = Input annual mileage
accumulation rates1
3 = Input registration
distributions by age1
4 = Input both annual mileage
accumulation rates and
registration distributions1
II
2.1.7
NEWFLG Flag for optional input of
modifications to basic
exhaust emission rates (BERs)
1 = Use MOBILE4 BERs
2 = Input one or more
alternate BERS1
II
2.1.8
IMFLAG Flag to include impact of
operating I/M program in
emission factor calculations
1 = No I/M program assumed
2 = I/M program assumed1
II
2.1.9
-------
2-50
Table 2.1-1 (continued)
FLAGS CONTROLLING INPUT TO AND EXECUTION OF MOBILE4
Record Variable
Number Name
Content and Codes
Format
Refer to
Section
ALHFLG Flag to correct exhaust
emission factors (gasoline-
fueled vehicles only) for:
a) air conditioning usage
b) extra vehicle load
c) trailer towing
d) humidity (NOx only).
1 = No corrections
2 = Input six values2
3 = Input ten values2
II
2.1 . 10
10 ATPFLG Flag to include impact of
of anti-tampering program
(ATP) on emission rates.
1 = No ATP assumed
2 = ATP assumed1
II
2.1.11
11 RLFLAG Flag for control of whether
and how refueling emission
factors are calculated.
1 = Uncontrolled rates
2 = Stage II VRS assumed1
3 = Onboard VRS assumed1
4 = Stage II and onboard
VRS assumed1
5 = No refueling emission
factors calculated
II
2.1.12
12 LOCFLG Flag for control of user
input of local area
parameter (LAP) record.
1 = One LAP record input
for each scenario2
2 = One LAP record input
for all scenarios1
II
2.1.13
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2-51
Table 2.1-1 (continued)
FLAGS CONTROLLING INPUT TO AND EXECUTION OF MOBILE4
Record Variable
Number Name
Content and Codes
Format
Refer to
Section
13 TEMFLG Flag for control of values of II 2.1.14
temperature to be used for
correcting emission factors
for effects of temperature
l = MOBILE4 calculates temperatures
to be used in correction of
emission factors, from input values
of minimum and maximum ambient daily
temperature; value read as input for
ambient temperature is overridden by
calculated values.
2 = Use to input value of ambient
temperature to correct emission
factors for temperature effects
Record(s) must appear in One-time data section.
Record(s) must appear in Scenario data section.
-------
2-52
Table 2.1-2
FLAGS CONTROLLING OUTPUT OF MOBILE4
Record Variable
Number Name
Content and Codes
Format
Refer to
Section
14 OUTFMT Selects the structure of II 2.1.15
formatted output report.
1 = 221-column numerical
2 = 140-column numerical
3 = 112-column descriptive
4 = 80-column descriptive
15 PRTFLG Selects pollutants for which
emission factors are to be
calculated and included in
output.
1 = HC only
2 = CO only
3 = NOx only
4 = All three pollutants
II
2.1.16
16 IDLFLG Controls calculation and
output of idle emission
factors.
1 = No idle EFs
2 = Include idle EFs
II
2.1.17
17 NMHFLG Selects total or non-methane
HC emission factor
calculations and output.
1 = Total HC EFs
2 = Non-methane HC EFs
II
2. 1.18
18 HCFLAG Controls printing of only II
total HC or all component HC
emission factors in output.
1 = No component EFs printed
2 = Total and component EFs printed
2.1.19
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2-53
Table 2.2-1
SUMMARY OF ALTERNATE BER RECORDS
(required in the One-time Data section if NEWFLG = 2)
Allowable
Record Field Content, Variable Name, and Codes Format Values
1 1 Number of BER records to follow 13,/ 1 to 100
(NEWCT)
2 l Code for region new BER II,IX 1 or 2
thru applies to: (NEWREG)
N+l
1 = low-altitude
2 = high-altitude
2
3
4
5
6
7
8
Code for vehicle type new 11, IX
BER applies to: (NEWVEH)
1 = LDGV 5 = LDDV
2 = LDGT1 6 = LDDT
3 = LDGT2 7 = HDDV
4 = HDGV 8 = MC
Code for pollutant new 11, IX
BER applies to: (NEWPOL)
1 = HC 2 = CO 3 = NOx
First model year new BER applies 12, IX
to (last 2 digits) (NEWMYF)
Last model year new BER applies 12, IX
to (last 2 digits) (NEWMYL)
New ZML (ZMLNEW) F6.2,1X
New DR (or DR1*) (DRNEW) F6.2,1X
New DR2* (A50NEW) F6.2,/
1 to 8
1 to 3
60-99,
00-20
60-99,
00-20
>_ 0.0
_> 0.0
>_ 0.0
* DR2 only for 1981 and later model year LDGVs (section 2.2.4.4).
Field 8 is blank otherwise, and the DR appears in Field 7.
-------
2-54
Table 2.2-2
SUMMARY OF I/M PROGRAM DESCRIPTIVE INPUT RECORD
(required in the One-time Data section if IMFLAG = 2)
Field Content, Variable Name, Codes Format
Allowable Refer to
Values Section
Program start year (ICYIM) 12, IX
(last 2 digits of first calendar
year of program operation)
60-99,
00-20
2A.1.2
2 Stringency level (ISTRIN)
(percent)
12, IX
10 to 50 2A.1.3
3 First model year (MODYR1) 12, IX
(last 2 digits of oldest
model year of vehicles
included in program)
41-99,
00-20
2A . 1 . 4
Last model year (MOOYR2)
(last 2 digits of latest
model year of vehicles
included in program)
12, IX
41-99, 2A.1.5
00-20
Waiver rate for pre-1981
model year vehicles
(WAIVER(D) (percent)
F2.0,IX
0 to 50 2A.1.6
Waiver rate for 1981 and F2.0,1X
later model year vehicles
(WAIVER(2)) (percent)
0 to 50 2A.1.6
Compliance rate (CRIM)
(percent)
F3.0,1X 0 to 100 2A.1.7
8 Program type (INTYP)
II,IX
l = Centralized
2 = Decentralized/Computerized
3 = Decentralized/Manual
1 to 3
2A.1.12
2A.1.13
2A.1.14
-------
2-55
Table 2.2-2 (continued)
SUMMARY OF I/M PROGRAM DESCRIPTIVE INPUT RECORD
(required in the One-time Data section if IMFLAG = 2)
Field Content, Variable Name, Codes Format
Allowable Refer to
Values Section
Inspection frequency (IFREQ) II,IX
1 = annual
2 = biennial
1 = not subject to inspection
2 = subject to inspection
1 or 2
2A.1.8
10
Vehicle types subject to
inspections (ILDT(4))
ILDT(l) — > LDGV
ILDT<2) — > LDGT1
ILDT(3) — > LDGT2
ILDT(4) — > HDGV
411, IX 1 or 2
(in each
column)
2A . l . 9
11 Test type (I TEST)
1 = Idle test
2 = 2500/Idle test
3 = Loaded Idle test
II, IX
1 or 2
2A.1.10
12 Flag to indicate whether 211
alternate I/M credits are to
be input by user (NUDATA(2))
NUDATA(l) —> For Tech I-II
NUDATA(2) —> For Tech IV+
1 = Use MOBILE4 I/M credits
2 = Read in alternate I/M credits
on logical I/O device unit 4
1 or 2
2A.1.11
2A.1.15
-------
2-56
Table 2.2-3
SUMMARY OF ATP DESCRIPTIVE INPUT RECORD
(required in the One-time Data section if ATPFLG = 2)
Field Content, Variable Name, Codes Format
Allowable Refer to
Values Section
1
2
3
4
Program start year (LAPSY) 12, IX
(last 2 digits of first
calendar year of ATP operation)
First model year (LAP1ST) 12, IX
(last 2 digits of oldest
model year of vehicles
included in ATP)
Last model year (LAPLST) 12, IX
(last 2 digits of latest
model year of vehicles
included in ATP)
Vehicle types subject to 4 11, IX
inspections (LVTFLG(4) )
60-99,
00-20
41-99,
00-20
41-99 or
00-20
1 or 2
(in each
column)
2A. 1.2
2A. 1.4
2A. 1 .5
2A . 1 . 9
Enter 1 or 2 for each vehicle
type, in this order:
LVTFLG(l)
LVTFLG(2)
LVTFLG(3)
LVTFLG(3)
—> LDGV
—> LDGT1
—> LDGT2
—> HDGV
1 = not subject to ATP inspection
2 = subject to ATP inspection
Program type (ATPPGM)
1 = Centralized
2 = Decentralized
II
1 or 2
2A.1.12
2A.1.13
-------
2-57
Table 2.2-3 (continued)
SUMMARY OF ATP DESCRIPTIVE INPUT RECORD
(required in the One-time Data section if ATPFLG =2)
Field Content, Variable Name, Codes Format
Allowable Refer to
Values Section
Inspection frequency
(ATPFQT)
1 = annual
2 = biennial
II, IX
1 or 2
2A.1.8
Compliance rate (CRATP)
(percent)
F4.0,1X 0 to 100 2A.1.7
Inspections performed
(DISTYP(B))
Enter 1 or 2 for each
inspection type, in
this order:
811
1 or 2
(in each
column)
DISTYP(l) —> Air pump system
DISTYP(2) —> Catalyst
DISTYP(3) —> Fuel inlet restrictor
DISTYP(4) —> Tailpipe lead deposit test
DISTYP(5) —> EGR system
DISTYP(6) —> Evaporative control system
DISTYP(7) —> PCV system
DISTYP(8) —> Gas cap
1 = Inspection not performed
2 = Inspection performed
2A.2.3
2A.2.4
2A
2,
2A.2.
2A.2,
2A.2,
2A.2,
2A.2.10
-------
2-58
Table 2.2-4
SUMMARY OF STAGE II AND ONBOARD VRS DESCRIPTIVE INPUT RECORDS
(required in the One-time Data section if RLFLAG = 2, 3, or 4)
Stage II VRS Input Record (required if RLFLAG = 2 or 4)
Allowable
Field Content, Variable Name, Codes Format Values
Stage II start year (IS2SY)
(last 2 digits of calendar year
in which Stage II requirement
is first effective)
12,IX
89-99,
00-20
Phase-in period (NPHASE)
(number of years allowed for all
stations subject to Stage II
requirement to complete installation)
II
1 to 9
Percent efficiency of Stage II VRS at
controlling refueling emissions from
LDGVs and LDGTs (PCTEL)
IX, 13
0 to 100
Percent efficiency of Stage II VRS at
controlling refueling emissions from
HDGVs (PCTEH)
IX, 13
0 to 100
Onboard
Field
VRS Input Record (recruired if RLFLAG = 3 or 4)
Content, Variable Name, Codes Format
Allowable
Values
1
2
Onboard start year ( IOBMY) 12, IX
(last 2 digits of first model year
vehicles are subject to onboard VRS
requirement)
Vehicle types covered (IVOB(4)) 411
Enter 1 or 2 for each vehicle type,
89-99,
00-20
1 or 2
(in each
column)
in this order:
IVOB(l) —> LDGV
IVOB(2) —> LDGT1
IVOB(3)
IVOBU)
—> LDGT2
—> HDGV
1 = No
2 = Yes
-------
2-59
Table 2.2-5
SUMMARY OF THE LOCAL AREA PARAMETER RECORD
(required in the One-time Data section if LOCFLG = 2,
and required in the Scenario Data section if LOCFLG = 1)
Allowable Refer to
Field Content, Variable Name, Codes Format Values Section
Scenario name (SCNAME) 4A4,IX N/A 2.2.9
ASTM volatility class Al A,B,C,D,E 2.2.10
(ASTMCL)
Minimum daily temperature F5.0 0.-100. 2.2.11
(TEMMIN), in °F
Maximum daily temperature F5.0 0.-120. 2.2.11
(TEMMAX), in °F
(TEMMIN and TEMMAX are used in the
diurnal index calculations for
evaporative HC emissions. If TEMFLG = 1,
they are also used in the calculation of
temperatures for correction of exhaust HC,
CO, and NOx emissions, hot soak evaporative
emissions, and running loss emissions.)
Base RVP (RVPBAS), in psi F5.1 7.0-15.2 2.2.12
(Current average fuel
volatility for the
geographic area of interest)
In-use RVP (IUSRVP), in psi F5.1,1X 7.0-15.2 2.2.13
(Regulated fuel volatility
limit after implementation
of in-use volatility control
in the geographic area of interest)
In-use start year (IUSESY) 12 89-99, 2.2.13
(Last 2 digits of first 00-20
calendar year of in-use
fuel volatility control)
-------
2-60
Table 2.3-1
SUMMARY OF THE SCENARIO RECORD(S)
Record 1: Scenario Descriptive Record (MANDATORY)
Allowable Refer to
Field Content, Variable Name, Codes Format Values Section
Region for which emission II,IX 1 or 2 2.3.1
factors are to be calculated
(IREJN)
1 = low-altitude
2 = high-altitude
Calendar year of evaluation 12 60-99, 2.3.2
(CY) 00-20
(Last 2 digits of calendar
year for which emission
factors are to be calculated,
as of January 1)
Average speed to be used in 2.5-55.0
emission factor calculations
(SPD or SPD<8)>
If SPDFLG = 1, one speed is 1X,F4.1
used for all vehicle types 2.3.3
-or-
If SPDFLG = 2, eight speeds
are used, as follows: 8(F4.1,]") 2.3.3
SPD(l) —> LDGV
SPD(2) —> LDGT1
SPD(3) —> LDGT2
SPD(4) —> HDGV
SPD(5) —> LDDV
SPD(6) —> LDDT
SPD(7) —> HDDV
SPD(8) —> MC
-------
2-61
Table 2.3-1 (continued)
SUMMARY OF THE SCENARIO RECORD(S)
Record 1: Scenario Descriptive Record (MANDATORY) (continued)
Allowable Refer to
Field Content, Variable Name, Codes Format Values Section
Ambient temperature (AMBT), 1X,F4.1 0.0-110.0 2.3.4
in °F
(If TEMFLG = 2, ambient
temperature is used to
correct exhaust, hot soak
evaporative, and running
loss emission factors for
temperatures other than 75°F)
Operating mode fractions 3(1X,F4.1) 0.0-100.0 2.3.5
(PCCN, PCHC, PCCC), in %
(Percent of VMT accumulated by:
PCCN —> Non-catalyst vehicles in cold-start mode
PCHC —> Catalyst-eguipped vehicles in hot-start mode
PCCC —> Catalyst-equipped vehicles in cold-start mode)
NOTE: Values MUST be entered for all fields in the scenario
descriptive record. There are NO DEFAULT VALUES for
these variables.
-------
2-62
Table 2.3-1 (continued)
SUMMARY OF THE SCENARIO RECORD(S)
Record 2: LAP record for this scenario on!
(OPTIONAL) (required only if LOCFLG = 1)
See Table 2.2-5
Record 3: VMT mix by vehicle type record
(OPTIONAL) (required only if VMFLAG = 2)
Field Content, Variable Name, Codes Format
Allowable Refer to
Values Section
1-8 VMT fraction accumulated by 8F4.3 0.0-1.0 2.2.2
each of eight
(VMTMIX(8))
VMTMIX(l) --
VMTMIX(2) —
VMTMIX(3) —
VMTMIX(4) —
VMTMIX(5) —
VMTMIX(6) —
VMTMIX(7) —
VMTMIX(8) —
Record 4: Additional
(OPTIONAL) (required
vehicle types and
2.3.6
> LDGV
> LDGT1
> LDGT2
> HDGV
> LDDV
> LDDT
> HDDV
> MC
Correction Factor record
only if ALHFLG = 2 or 3)
Field Content, Variable Name, Codes Format
Allowable Refer to
Values Section
1 Air conditioning usage F4.2 0.0-1.0 2.3.8.3
fraction (AC)
(Percent of all A/C-equipped
vehicles assumed to actually
be using their A/C)
Note: If ALHFLG = 2, input value of AC is used to calculate
correction factor.
If ALHFLG = 3, input value is overridden by calculated
value (see 2.3.8.7); however, a value must be entered here.
-------
2-63
Table 2.3-1 (continued)
SUMMARY OF THE SCENARIO RECORD(S)
Record 4: Additional Correction Factor record (continued)
(OPTIONAL) (required only if ALHFLG = 2 or 3)
Allowable Refer to
Field Content, Variable Name, Codes Format Values Section
2-4 Extra load fraction (XLOADO)) 3F4.2 0.0-1.0 2.3.8.4
(Percent of vehicles assumed to
be carrying additional 500 Ibs)
XLOAD(l) —> LDGV
XLOAD(2) —> LDGT1
XLOADO) — > LDGT2
5 Trailer towing fraction F4.2 0.0-1.0 2.3.8.5
or (TRAILR or TRAILRU)) or
5-7 (Percent of vehicles assumed 3F4.2
to be towing trailers)
Note: If ALHFLG = 2, one value is required and is used to
calculate correction factor for all three vehicle types.
If ALHFLG = 3, three values are required and are used to
calculate correction factors as follows:
TRAILR(l) -> LDGV TRAILR(2) -> LDGT1 TRAILR(3) -> LDGT2
6 Absolute humidity level F4.0 20.-140. 2.3.8.6
or (ABSHUM)
8 (Humidity in grains water per
pound dry air, used to correct
exhaust NOx emission factors)
9, 10 Dry bulb and wet bulb 2F4.0 0.-110. 2.3.8.7
temperatures (DB,WB), in °F
If ALHFLG = 3 only, these temperatures are used to
calculate a "discomfort index," which in turn is used to
estimate an A/C usage fraction (which then overrides the
value input for AC in Field 1 of this record).
-------
2-64
Table 2.4-1
SUMMARY OF THE MOBILE4 INPUT RECORD SEQUENCE
Input Record Sequence
1 PROMPT flag record
(1-3 IOUNEW values)*
1 PROJID record
1 TAMFLG flag record1
1 SPDFLG flag record1
1 VMFLAG flag record1
1 MYMRFG flag record1
1 NEWFLG flag record1
1 IMFLAG flag record1
1 ALHFLG flag record1
1 ATPFLG flag record1
1 RLFLAG flag record1
1 LOCFLG flag record1
l TEMFLG flag record1
1 OUTFMT flag record1
1 PRTFLG flag record1
1 IDLFLG flag record1
1 NMHFLG flag record1
1 HCFLAG flag record1
(20 or 40 tampering records)2
if TAMFLG = 2
(1 VMT mix record) if VMFLAG = 3
(16 mileage accumulation rate
records) if MYMRFG = 2 or 4
(16 registration distribution
records) if MYMRFG = 3 or 4
(1 to 100 basic emission rate
records) if NEWFLG = 2
(1 I/M program descriptive
record) if IMFLAG = 2
(1 ATP descriptive record) if ATPFLG = 2
(1 or 2 refueling emission VRS descriptive
records)1 if RLFLAG = 2, 3, or 4
(1 LAP record) if LOCFLG = 2
1 Scenario descriptive record
(1 LAP record) if LOCFLG = 1
(1 VMT mix record) if. VMFLAG = 2
(1 additional correction factor
record) if ALHFLG = 2 or 3
Input
Section
CONTROL
CONTROL
CONTROL
CONTROL
CONTROL
CONTROL
CONTROL
CONTROL
CONTROL
CONTROL
CONTROL
CONTROL
CONTROL
CONTROL
CONTROL
CONTROL
CONTROL
CONTROL
CONTROL
ONE-TIME
ONE-TIME
ONE-TIME
ONE-TIME
ONE-TIME
ONE-TIME
ONE-TIME
ONE-TIME
ONE-TIME
SCENARIO
SCENARIO
SCENARIO
Refer to
Section
2.1.1
2. 1.2
2. 1.3
2.1.4
2.1.5
2.1.6
2.1.7
2.1.8
2.1.9
2. 1.10
2.1.11
2.1.12
2. 1.13
2.1.14
2.1. 15
2.1.16
2.1.17
2.1.18
2.1.19
2.2.1
2.2.2
2.2.3
2.2.3
2.2.4
2.2.5
2.2.6
2.2.7
2.2.8
2.3.1
2.2.8
2.2.2
SCENARIO
2.3.8
Required only if reassignment of output device numbers is
desired.
These 16 flags are entered on one record (format 1611) if
PROMPT = 3 or 4.
20 records if IMFLAG = 1; 40 records if IMFLAG = 2.
Stage II record if RLFLAG = 2; onboard record if RLFLAG = 3;
both records if RLFLAG = 4.
-------
2-65
Appendix 2A
INSPECTION/MAINTENANCE AND ANTI-TAMPERING
PROGRAM TERMINOLOGY DEFINITIONS
This appendix discusses the terminology used to describe
inspection and maintenance (I/M) and anti-tampering (ATP) programs
for purposes of modeling the emission benefits of such programs
using MOBILE4. In general, it is assumed that the I/M program is
mandatory, periodic, and covers a well defined group of vehicles.
There are many details (such as instrument specifications) which
are beyond the scope of this listing. Program planners should
consult with EPA (Technical Support Staff, 313/668-4367 or FTS
374-8367) if there is any question as to what is required of I/M
programs.
2A.1 I/M PROGRAM TERMINOLOGY
2A.1.1 I/M
I/M refers to "inspection and maintenance" programs which are
inspections of vehicles using a measurement of tailpipe emissions
and which require that all vehicles with tailpipe emissions higher
than the program outpoints be repaired to pass a tailpipe emission
retest. (For convenience, such tailpipe I/M programs and anti-
tampering programs are sometimes referred to collectively as
simply "I/M programs" in other EPA documents.)
2A.1.2 Start Year
The year in which the periodic inspection program begins to
require both inspection and repairs is called the start year.
MOBILE4 only allows for a January 1st start date. Other start
dates will require interpolation between two MOBILE4 runs to give
accurate estimates of benefits.
2A.1.3 Stringency
Stringency is the tailpipe emission test failure rate among
pre-1981 model year passenger cars or pre-1984 light-duty trucks
expected in an I/M program based on its short test emission
cutpoints. The expected failure rate can be determined by
applying the program cutpoints to a representative sample of
vehicles tested in a survey. Failure rates reported by the
-------
2-66
program would not be used to determine stringency if there is the
possibility of significant testing or data reporting errors.
MOBILE4 assumes that the failure rate remains fixed at the
stringency level for each evaluation year. MOBILE4 will not allow
a stringency less than 10% or greater than 50%.
2A.1.4 First Model Year
The first model year refers to the oldest model year vehicle
which is always included in the inspection program. MOBILE4
assumes that all vehicle classes have the same model year coverage
and does not allow for a separate coverage for each vehicle
class. Some programs do not fix the model years covered by the
program, and instead use a coverage "window" to define which
vehicles must be inspected. For example, such a program may cover
only vehicles 15 years old or younger. Such programs cannot be
modeled accurately using MOBILE4 without special assistance.
2A.1.5 Last Model Year
The last model year refers to the youngest (newest) model
year vehicle which is always subject to the inspection program.
This allows for a program to cover only particular model years.
Most programs routinely include the new model year vehicles in the
program as they reach one year old. It is recommended that the
maximum allowable last model year (2020) be input as the last
model year, unless a special case requires some other input.
MOBILE4 I/M credits already assume that vehicles less than one
year old are exempt from inspection, so that input of the maximum
last model year allows for maximum flexibility.
2A.1.6 Waivers
Many I/M programs waive the requirement to pass a retest if
certain defined criteria are met. MOBILES normally assumed that
all vehicles of the model years and vehicle classes indicated by
the user input complied with the program outpoints. Waivers are
often granted in I/M programs, however, for vehicles whose owners
have spent over a set dollar limit in attempting to comply with
the program retest requirement.
The waiver rate input in MOBILE4 reduces the estimated
benefit of the I/M program design. The waiver rate is always
calculated as a percent of non-duplicate initial test failures.
MOBILE4 assumes that tampered or misfueled vehicles cannot receive
waivers, and does not reduce the ATP benefit based on the waiver
rate.
-------
2-67
2A.1.7 Compliance Rate
Compliance rate refers to the level of compliance with the
inspection program. For example, assume a program required that
all passenger cars be inspected each year, and that there were
100,000 passenger cars registered in the area covered by the
program. If, in a given year, only 95,000 passenger cars
completed the inspection process to the point of receiving a final
certificate of compliance or waiver, it could be assumed that the
remaining 5,000 vehicles were avoiding the program inspection
requirement. The compliance rate for this program would then be
95%. The number of initial inspections should not be used to
calculate the compliance rate since some cars may drop out after
failing one or more tests. The compliance rate input is also used
to account for vehicles which are waived from compliance without
any testing (e.g., vehicles with special testing problems or
vehicles owned by certain types of owners).
MOBILE4 uses a single compliance rate to reduce both the I/M
and ATP portions of the program benefits. The reduction in
benefit is not linear. The benefit loss per vehicle assumes that
the failure rate among non-complying vehicles will be larger than
the expected failure rate in the fleet. As the rate of
non-compliance increases, the non-complying failure rate will
approach and finally equal the expected failure rate.
The following table shows the loss of benefit assumed for the
enforcement fraction:
Compliance
Rate
100%
99%
98%
97%
96%
95%
90%
85%
80%
75%
70%
50%
Non-
Compliance
Rate
0%
1%
2%
3%
4%
5%
10%
15%
20%
25%
30%
50%
Non-Complier
Failure Rate
Adjustment
2.0
2.0
2.0
2.0
2.0
1.5
1.4
1.3
1.2
1.1
1.0
1.0
Fraction
Benefit
Loss
.000
.020
.040
.060
.080
.095
.169
.238
.302
.361
.415
.615
Fraction
Benefit
Remaining
1.000
.980
.960
.940
.920
.905
.831
.762
.698
.639
.585
.385
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2A.1.8 Inspect i on Frequency
MOBILE4 allows for two inspection frequencies. Annual means
that all covered vehicles must be inspected once each year.
Biennial means that each vehicle is inspected once every two
years, such that half of each model year is inspected each year.
Any other inspection frequency would require alternate I/M credits
provided by EPA.
2A.1.9 Vehicle Classes
MOBILE4 program benefits are calculated separately for each
gasoline-fueled vehicle class. No emission benefit is estimated
for diesel fueled vehicles or motorcycles. The vehicle class
designations are based on the certification standards
definitions. The classes are:
o LDGV - light-duty gasoline-fueled vehicles which are
passenger vehicles.
o LDGT1 - light-duty gasoline-fueled trucks less than
6,000 Ibs gross vehicle weight. These are the lighter
pick-up trucks and vans.
o LDGT2 - light-duty gasoline-fueled trucks greater than
6,000 Ibs gross vehicle weight, but less than 8,500
Ibs. These are the heavier pick-up trucks and vans and
many commercial trucks.
o HDGV - heavy-duty gasoline-fueled vehicles greater than
8,500 Ibs gross vehicle weight. These are thfe heavier
commercial trucks, including highway hauling trucks.
Many areas do not use the same vehicle class designations in
their vehicle registration data as are used in MOBILE4. In these
cases care must be taken not to claim coverage for too many
vehicles.
2A.1.10 I/M Test Types
There are three I/M test types normally allowed in MOBILE4.
These test types only apply to the inspection of 1981 and newer
model year passenger cars and 1984 and newer light-duty trucks.
The concept of stringency already takes into account the effect of
the test type on the benefits from older vehicles. The chosen
test type is assumed to be applied to all 1981 and newer passenger
cars and 1984 and newer light-duty trucks both at the initial
inspection and the retest.
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o Idle Test refers to a measurement of HC and CO emission
concentrations of a fully warmed vehicle as it idles in
neutral or park.
o 2500/1 die Test refers to a measurement of HC and CO
emission concentrations of a fully warmed vehicle at
2500 rpm in neutral or park and again at idle. The
vehicle must pass both at idle and at 2500 rpm in order
to pass the test.
o Loaded/1 die Test refers to a measurement of HC and CO
emission concentrations of a fully warmed vehicle at
30 + 1 mph on a chassis dynamometer at a constant load
and again at idle in neutral or park. The vehicle must
pass both at idle and at load in order to pass the test.
2A.1.11 Alternate I/M Credits
In special cases where the design of the I/M program to be
modeled does not fit into any of the categories defined in
MOBILE4, the model allows the user to supply a set of factors that
will be used to determine the I/M program benefits. Normally
these factors will be supplied by EPA at the request of the
program manager or air quality planner.
2A.1.12 Centralized
Centralized inspection programs refer to those programs which
completely separate the inspection of vehicles from the repairs.
Usually a few high-volume inspection stations, run either by the
local agency itself or by a contractor, will perform all initial
tests and retests after repair. Garages and other repair
facilities are not allowed to perform official tests. Centralized
programs are the standard used to determine the emission benefits
for I/M and ATP program designs.
2A.1.13 DecentraIized
Decentralized inspection programs refer to those programs
where the local program agency licenses stations to perform
official inspections and reinspections. These licensed inspection
stations are allowed to perform repairs on the vehicles they
inspect. The number of licensed inspections stations in
decentralized programs is larger and the volume per station is
smaller than for centralized programs.
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Decentralized programs have been found to be less effective
than centralized designs. As a result, MOBILE4 will reduce the
emission benefits from a centralized design by 50% for the I/M
portion and 50% for the ATP portion of the program if a
decentralized design is chosen.
2A. 1.14 Computerized Inspection
Some decentralized I/M programs reguire the use of
"computerized" emission analyzers. These analyzers contain small
computers which keep track of all official inspection activity,
automatically calibrate the instrumentation and prompt the
inspector during the inspection procedure. The computer also
prepares a machine-readable record of all official inspections and
calibrations and will not allow inspections whenever it determines
the instrumentation to be out of calibration.
Computerized analyzers improve the performance of the I/
portion of a decentralized inspection program. MOBILE4 assumes
that the I/M portion of a decentralized computerized inspection
program will be as effective as a centralized program of similar
stringency. Decentralized computerized inspection programs will
still have the benefits from the ATP portion of the program
reduced by 50%.
2A.1.15 Tech l-lI and Tech IV+
The calculation of I/M benefits for MOBILE4 was done by
"technology group," which can roughly be determined by model year
for each vehicle type. These technology groups have come to be
referred to by numbers. The table below summarizes the technology
groupings used in MOBILE4 and their respective application to
gasoline-fueled passenger cars and light trucks.
Technology Model Years Covered
Grouping LDGV LDGT1 LDGT2
I Pre-1975 Pre-1975 Pre-1979
II 1975-80 1975-83 19.79-83
IV+ 1981+ 1984+ 1984+
Sets of alternate I/M credits may contain both Tech I and II
credits, only Tech IV+ credits, or Tech I, II, and IV+ credits
together. This is usually indicated in the header block of the
alternate I/M credit deck.
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2A.2 ATP TERMINOLOGY
This section discusses the terminology used to describe ATP
inspections for purposes of modeling the emission benefits of such
programs using MOBILE4. In general, it is assumed that the
program is mandatory, periodic, and covers a well defined group of
vehicles. A program which inspects for tampering only when a
vehicle has failed its tailpipe I/M inspection, or only when a
vehicle owner requests a test waiver, is not considered to have an
ATP in MOBILE4.
It is also assumed that the inspections are primarily visual
rather than functional, and involve no disassembly or
disconnections to gain access to hidden components (other than
removal of the gas cap to view the fuel inlet restrictor) .
However, program planners are encouraged to define failure in
broad enough terms of visual damage and proper operating condition
so that any emission control component determined by the inspector
to be non-functional can be properly failed and repaired. There
are many details (such as replacement catalyst specifications)
which are beyond the scope of this listing. Program planners
should consult with EPA's Office of Mobile Sources (Technical
Support Staff, 313/668-4367 or FTS 374-8467) if there is any
question as to what is required of ATP inspections.
2A.2.1 ATP
ATPs are "anti-tampering programs," which are periodic
inspections of vehicles to detect damage to, disablement of, or
removal of emission control components. Owners are required to
restore the vehicle's emission control system and have the vehicle
reinspected. Note that programs that inspect for tampering only
those vehicles failing an I/M tailpipe test are not considered for
MOBILE4 modeling purposes to have an ATP, and should not attempt
to derive ATP emission reduction credits.
2A.2.2 Tampering and Misfueling
Any physical damage to, or disablement or removal of, an
emission control component is considered tampering in MOBILE4.
This does not limit tampering only to deliberate disablements or
only to those disablements of which the vehicle owner is aware.
As a result, tampering can often be a result of poor maintenance
as opposed to some action by the vehicle owner or a service
mechanic. Misfueling is the use of leaded fuel in any vehicle
which is equipped with a catalytic converter. This includes
inadvertent use of leaded fuel without the knowledge of the
vehicle owner.
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2A.2.3 Air Pump Inspection
Air pump systems supply fresh air needed by the catalytic
converter to reduce engine emissions before they leave the
tailpipe. Inspectors should check for missing belts and hoses and
proper connection at the exhaust manifold. Sometimes the entire
pump and its plumbing are removed. A valve is sometimes used to
route air away from the exhaust stream during certain operating
modes. This valve should be checked for proper hose and wire
connections. Often the air is injected directly into the
catalytic converter underneath the vehicle. If so, this
connection should be checked. Any missing, damaged or altered
components of the air pump system should be replaced.
2A.2.4 Catalyst Inspection
The catalytic converter, sometimes referred to simply as the
catalyst, oxidizes excess hydrocarbon and carbon monoxide from the
engine exhaust into water and carbon dioxide. Newer catalysts
also reduce oxides of nitrogen in the exhaust. The metals which
accomplish this task are most commonly coated on a ceramic
honeycomb inside the stainless steel shell of the catalyst. The
catalyst resembles a muffler in some ways, but would not be
confused with a muffler because it is farther forward on the
vehicle, and its stainless steel shell will not rust.
Some cars will have more than one catalyst, so the number of
catalysts expected should be determined before the inspection
begins. Some catalysts are located very near the exhaust
manifold, so the inspector should be sure to check the entire
length of the exhaust piping from the exhaust manifold to the
muffler before determining that the catalyst is not present.
Emission credit should not be claimed in MOBILE4 unless
regulations provide a mechanism to assure that failed cars are
correctly repaired with OEM or approved aftermarket replacements.
Program planners should consult with EPA to avoid incorrectly
claiming credit.
2A.2.5 Fuel Inlet Restrictor Inspection
Vehicles requiring the use of only unleaded gasoline have
been equipped with fuel inlets that only allow use of narrow fuel
nozzles. Leaded fuel is required to be dispensed only from pumps
using wider nozzles. Any vehicle found to have a fuel inlet which
allows a leaded fuel nozzle to be inserted, such as having the
nozzle size restriction removed, is assumed to have used leaded
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fuel. Leaded fuel permanently reduces the ability of the
catalytic converter to reduce emissions. Therefore, vehicles
found with a fuel inlet which allows insertion of a leaded fuel
nozzle should be required to replace the catalytic converter. In
addition, the vehicle's fuel inlet should be repaired to only
allow the insertion of unleaded fuel nozzles.
Repair of the fuel inlet restrictor only is not considered a
repair which will reduce the emissions of the vehicle. The damage
to the emission control of the vehicle occurs in the catalyst. It
is the catalyst which must be replaced to result in any
substantial emission reduction. The inlet restrictor must be
replaced simply as protection for the new catalyst.
The model assumes that inspectors are not allowed to skip
this inspection for such reasons as that the fuel inlet is
concealed by a locked door.
2A.2.6 Tailpipe Lead Detection Test
Leaded fuel permanently reduces the ability of the catalytic
converter to reduce engine emissions before they leave the
tailpipe. Therefore, vehicles found to have used leaded fuel
should be required to replace the catalytic converter. EPA has
allowed for the use of a lead detection test in the vehicle
tailpipe as a method to detect the use of leaded fuel. Since this
is a chemical test, care must be taken to assure that the test is
properly conducted and that the results are properly interpreted.
Vehicles with evidence of lead deposits in the tailpipe have
used leaded fuel. The damage to the emission control of the
vehicle occurs in the catalyst. It is the catalyst which must be
replaced to result in any substantial emission reduction. (The
tailpipe should also be replaced simply to avoid failing the test
at the next inspection.) ATPs which require failure of both the
fuel inlet restrictor inspection and the tailpipe lead detection
test before requiring replacement of the catalyst get credit for
neither in MOBILE4, and should not indicate either inspection on
the input records.
2A.2.7 EGR Inspection
The exhaust gas recirculation (EGR) system reduces oxides of
nitrogen by routing some of the exhaust back into the intake
manifold. The primary component of the system is the valve which
controls the flow between the exhaust and intake manifolds,
however, most systems are quite complex with various sensors and
valves which control the operation of the system. Hoses may be
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plugged, either deliberately or by neglect. Any system observed
with missing or damaged components or misrouted or plugged hoses
and wires should be failed and repaired.
2A.2.8 Evaporative Control System
The evaporative control system collects gasoline vapors from
the gas tank and carburetor bowl and stores them in a charcoal
canister. During certain engine operations, the canister purges,
releasing the vapors which are routed to the engine to be burned.
In addition to the evaporative canister itself, the system
includes varying numbers of hoses, wires and control valves.
Hoses may be plugged, either deliberately or by neglect. Any
system observed with missing or damaged components or misrouted or
plugged hoses and wires should be failed and repaired.
2A.2.9 PCV Inspection
The positive crankcase ventilation (PCV) system routes the
vapors from the crankcase to the intake manifold where they can be
burned by the engine. The PCV system has two major loops. The
most critical connects the crankcase with the throttle or the
intake manifold with a hose and usually contains a valve. Another
hose connects the crankcase with the air cleaner to provide the
crankcase with filtered fresh air. Any system observed with
damaged or missing components or with hoses misrouted or plugged,
should be failed and repaired.
2A.2.10 Gas Cap Inspection
Gas caps are actually part of the evaporative control
system. Without a properly operating gas cap, fuel vapors from
the gas tank would escape. On some vehicles, a missing gas cap
will also cause the evaporative system canister to purge
incorrectly. Inspectors should examine the fuel inlet area of
each vehicle to determine that the gas cap is present. If not,
the vehicle should be failed and the gas cap replaced. Inspectors
should not be allowed to skip this inspection for such reasons as
that the fuel inlet is concealed by a locked door.
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Appendix 2B
RVP AND ASTM CLASS DETERMINATION GUIDANCE
This appendix describes how to determine the average in-use
volatility (as measured by Reid vapor pressure, or RVP) for
gasoline in a given city, metropolitan statistical area (MSA),
or state in a way that is consistent with other MOBILE4 inputs
and is acceptable to EPA for use in preparing State
Implementation Plans and similar analyses. It also describes
how to determine the ASTM Class for a given city or state for
MOBILE4 modeling purposes.
2B.1 RVP GUIDANCE
2B.1.1 Determine the period from which the relevant design
value (ozone or carbon monoxide) is calculated. This
is normally a three-year period, and currently
encompasses the years 1984, 1985, and 1986.
2B.1.2 The most recent of the three years included in the
relevant design value calculation is the year for
which RVP is to be determined as described below.
2B.1.3 The easiest method of determining the value of RVP to
use in MOBILE4 is to use the American Society for
Testing and Materials' (ASTM's) suggested limit,
based on the month and year and the area for which
RVP is to be determined. To determine the
appropriate ASTM class for the area to be modeled,
see section 2B.2. EPA will accept use of the value
determined in this way for base RVP in MOBILE4 runs
used by the States in their inventory development and
other SIP-related mobile source modeling.
An area may also choose to determine base RVP for a
given area through the use of gasoline survey data.
EPA wil also accept the use of RVP determined in
accordance with the guidance below from either of two
regularly published gasoline volatility surveys, by
the National Institute for Petroleum and Energy
Research (NIPER) and the Motor Vehicle Manufacturers'
Association (MVMA). Section 2B.1.5 is applicable if
the NIPER survey is used, and section 2B.1.6 is
applicable if the MVMA survey is used.
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2B.1.4 Determination of RVP by ASTM class:
2B. 1.4.1 Determine the ASTM volatility class for the area of
interest, as outlined in section 2B.2.
2B.1.4.2 For HC (ozone) modeling, use the July ASTM class.
2B.1.4.3 For CO modeling, use the ASTM class for the month in
which the current design value was recorded. See
2B.2.2 under "ASTM Class Guidance," below.
2B.1.4.4 Use the corresponding value of RVP as the base RVP
(RVPBAS) in MOBILE4:
ASTM Class: A B C D E
RVP limit: 9.0 10.5 11.5 13.5 15.0
2B.1.5 If the NIPER survey is used:
2B.1.5.1 Obtain the appropriate edition of the report "Motor
Gasolines," published semi-annually (winter and
summer surveys) by NIPER.
The cost per report is $35, and it is available from:
Cheryl L. Dickson
National Institute for Petroleum and Energy Research
P. 0. Box 2128
Bartlesville, OK 74005
Phone (918) 336-2400
2B.1.5.1.1 For HC (ozone) modeling, the summer NIPER survey
should be used.
2B.1.5.1.2 For CO modeling, the appropriate NIPER survey to use
depends on the temperatures associated with
exceedances of the National Ambient Air Quality
Standard (NAAQS) for CO for the area being modeled.
If that temperature is 50°F or higher, and/or the
majority of exceedances of the CO NAAQS occurred
during the "summer" months (May-Sept), the use of the
summer NIPER survey is recommended. If that
temperature is less than 50°F, and/or the majority of
exceedances of the CO NAAQS occurred during the
"winter" months (Oct-April), the use of the winter
NIPER survey is recommended.
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2B.1.5.2 From this report, determine the district(s) of
interest. The NIPER survey divides the country into
seventeen districts, which are described in a table and
illustrated on a map of the U.S.
2B.1.5.3 If the RVP of a specific city or MSA is desired, use
the district in which the city or MSA is located. If
the RVP for an entire state is desired, and that state
lies entirely within one district, use that district;
if the state lies within two or more districts, average
the values obtained in 2B.1.4.4 and 2B.1.4.5 for each
of the districts.
2B.1.5.4 Find the average RVP values for the district(s) of
interest from Table 4 of the NIPER survey. Table 4
presents the average RVP of three grades of gasoline
for each district: regular unleaded, regular leaded,
and premium unleaded.
The distinction between the "regular" and "premium"
grades is based on the antiknock (octane) index of the
fuel, defined as the sum of the Research octane and
Motor octane numbers divided by two: (R+M)/2. In
Table 4, the grades of gasoline are defined by:
Regular unleaded: (R+M)/2 < 90.0
Premium unleaded: (R+M)/2 _> 90.0
Regular leaded: (R+M)/2 < 93.0
2B.1.5.5 Determine the average RVP of gasoline in a district by
weighting these three values at 50 percent regular
unleaded, 25 percent premium unleaded, and 25 percent
regular leaded:
District average RVP =
0.50 * (district average RVP of regular unleaded) +
0.25 * (district average RVP of premium unleaded) +
0.25 * (district average RVP of regular leaded)
2B.1.5.6 The value determined in 2B.1.5.5 (or the average of the
values obtained in 2B.1.5.5 if the area for which the
average RVP is being determined encompasses two or more
districts) is then used as the value of base RVP
(RVPBAS) in MOBILE4.
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2B.1.6 If the MVMA survey is used:
2B.1.6.1 Obtain the appropriate edition of the "MVMA National
Gasoline Survey," published semi-annually (winter and
summer seasons) by the Motor Vehicle Manufacturers'
Association. Ordering and price information is
available from:
Mr. James Steiger
Motor Vehicle Manufacturers' Association
300 New Center Building
Detroit, MI 48202
Phone (313) 872-4311
2B.1.6.1.1 For HC (ozone) modeling, the summer MVMA survey should
be used.
2B.1.6.1.2 For CO modeling, the appropriate MVMA survey to use
depends on the temperatures associated with
exceedances of the National Ambient Air Quality
Standard (NAAQS) for CO for the area being modeled.
Determine the temperature in accordance with the
guidance provided in Appendix 2C of this chapter. If
that temperature is 50°F or higher, and/or the
majority of exceedances of the CO NAAQS occurred
during the "summer" months (May-Sept), the use of the
summer MVMA survey is recommended. If that
temperature is less than 50°F, and/or the majority of
exceedances of the CO NAAQS occurred during the
"winter" months (Oct-April), the use of the winter
MVMA survey is recommended.
2B.1.6.2 Determine the city or cities of interest that are
included in the MVMA survey:
2B. 1.6.2.1 If the average RVP for a specific city (or MSA) is
desired, and that city is included in the MVMA survey,
use the values for that city.
2B.1.6.2.2 If the average RVP for a specific city (or MSA) is
desired, and that city is not included in the MVMA
survey, use the values for the city that is both
closest to the city of interest and of the same ASTM
volatility class. (Determination of ASTM volatility
class is discussed below.)
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2B.1.6.2.3 If the average RVP for an entire state is desired and
a city within that state is included in the MVMA
survey, use the values for that city. If the average
RVP for an entire state is desired and two or more
cities in that state are included in the MVMA survey,
average the values determined in 2B.1.6.3 and 2B.1.6.4
for each of those cities. If no city within the state
for which average RVP is desired is included in the
MVMA survey, use the values for the major city that is
both nearest to the state of interest and of the
same ASTM volatility class.
2B.1.6.3 Find the average RVP value(s) for the city or cities
selected in section 2B.1.5.2 from the summary tables
that appear near the end of the MVMA survey. The
average RVP for regular unleaded gasoline is provided
for all cities; the average RVP for premium unleaded
and/or regular leaded gasoline is also provided for
many cities.
2B.1.6.4 Determine the average RVP value(s) for the area of
interest from the average RVP values supplied for
different grades of gasoline as follows:
2B.1.6.4.1 If only the average RVP for regular unleaded gasoline
is provided, use that value.
2B.1.6.4.2 If the average RVP for regular unleaded and one of the
other two grades (either premium unleaded or regular
leaded) is provided, weight the values at 75 percent
regular unleaded and 25 percent of the other grade for
which the RVP is provided:
Average RVP =
0.75 * (average RVP of regular unleaded) +
0.25 * (average RVP of either regular leaded
or premium unleaded)
2B.1.6.4.3 If the average RVP is provided for all three grades
for the city of interest, weight the values at 50
percent regular unleaded, 25 percent regular leaded,
and 25 percent premium unleaded:
Average RVP =
0.50 * (average RVP of regular unleaded) +
0.25 * (average RVP of premium unleaded) +
0.25 * (average RVP of regular leaded)
2B.1.6.5 The value determined in 2B.1.6.4 is then used as the
value of base RVP (RVPBAS) in MOBILE4.
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2B.2 ASTM CLASS GUIDANCE
ASTM defines five volatility classes (designated by the
letters A thru E) and assigns one or two of these classes to each
state, for each month of the year. This guidance describes how to
determine the appropriate ASTM class for use as input to MOBILE4.
2B.2.1 The ASTM volatility classes are specified in ASTM
standard D 439. The most recent edition of this
standard was issued in 1986 (D 439-86). The standard
appears in the 1987 Annual Book of ASTM Standards
(Section 5: Petroleum Products, Lubricants, and Fossil
Fuels; Volume 05.01: Petroleum Products and Lubricants
(I): D 56 - D 1947). This is available in most large
libraries, or may be obtained directly from:
American Society for Testing and Materials
1916 Race Street
Philadelphia, PA 19103
Phone: (215) 299-5400
2B.2.2 Table 2 in ASTM D 439 lists the volatility class for
each month of the year, for each state or portion of
state (see below). In those cases where more than one
class is listed, select the class with the lower
volatility limit (i.e., the letter closer to "A").
Example: Alabama is listed as "C/B" for July; "B" is
the appropriate value to select for MOBILE4 use.
2B.2.2.1 For HC (ozone) modeling, use the July ASTM class.
2B.2.2.2 For CO modeling, use the ASTM class for the month in
which the current CO design value was recorded. (For
example, if the 1984-86 CO design value was recorded on
August 29, 1986, use the August ASTM class.)
2B.2.3 For states divided into two or more regions in the ASTM
standard, select the value for that portion of the
state containing the majority of the population:
State Portion of state to use
CA N coast, S coast, interior
IL N of 40° latitude
NV S of 38° latitude
NM N of 34° latitude
OR W of 122° longitude
TX E of 99° longitude
WA W of 122° longitude
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2B.2.4 If the ASTM class of. a specific city in one of the
states listed in 2B.2.3 is desired, select the value
for that portion of the state in which that city lies.
2B.2.5. The letter determined in 2B.2.2, 2B.2.3, or 2B.2.4
above is then used as the value of ASTM class
(ASTMCL) in MOBILE4.
(Note: If a value other than one of the five letters
A, B, C, D, or E is input as the value for ASTM
class, MOBILE4 will issue an error message and the
run will not be executed.)
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Appendix 2C
MINIMUM, MAXIMUM. AMBIENT TEMPERATURE DETERMINATION GUIDANCE
This appendix provides suggested guidance on determination of
appropriate temperature inputs for use in MOBILE4, for SIP-related
ozone (HC) and CO modeling.
2C.1 Temperature Guidelines for Evaporative
Hydrocarbon Emissions Calculations
2C.1.1 Determine the period from which the ozone design value is
calculated. This is normally a three year period and
currently encompasses the years 1984 - 1986.
2C.1.2 List the 10 highest daily one-hour ozone concentrations
and the dates of those concentrations for that period.
2C.1.3 Order the Local Climatological Data Monthly Summary for
those dates and the area being modeled. Both individual
monthly and annual subscription reports are available from:
National Climatic Data Center
Federal Building
Asheville, NC 28801-2696
Telephone: 704-259-0682
FTS 672-0682
Individual monthly reports cost $1.00. Annual
subscriptions cost $8.50 per year, plus $5.00 the first
year to initiate the subscription. The National Climatic
Data Center accepts Visa, MasterCard, American Express,
and check or money order.
2C.1.4 For each of the 10 highest daily one-hour ozone
concentrations and dates listed in 2C.1.2, transcribe the
maximum and minimum temperatures occurring on those dates
according to the Local Climatological Data Monthly Summary.
The maximum daily temperature is located in column 2 on
page one of the Summary. The minimum daily temperature is
located in column 3 on page one of the Summary.
2C.1.5 Calculate the average maximum temperature occurring on
those 10 days. Use this average maximum temperature as
the value of maximum daily temperature in the One-time
Data section of MOBILE4 (see section 2.2.11).
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2C.1.6 Calculate the average minimum temperature occurring on
those 10 days. Use this average minimum temperature as
the value of minimum daily temperature in the One-time
Data section of MOBILE4 (see section 2.2.11).
2C.1.7 Calculate the ambient temperature, used in the Scenario
descriptive record of MOBILE4 (see section 2.3.4), as
follows:
Ambient Temperature = [2/3] *
[Average Maximum Temperature
- Average Minimum Temperature]
-i- [Average Minimum Temperature]
2C.2 Temperature Guidelines for Carbon
Monoxide Emissions Calculations
2C.2.1 Determine the period from which the carbon monoxide design
value is calculated. This is normally a three-year period
and currently encompasses the years 1984 - 1986.
2C.2.2 List the 10 highest non-overlapping 8-hour carbon monoxide
concentrations and the dates of those concentrations for
that period.
2C.2.3 Order the Local Climatological Data Monthly Summary for
those dates and the area being modeled (see section
2C.1.3.)
2C.2.4 For each of the 10 highest non-overlapping 8-hour carbon
monoxide concentrations and dates listed in 2C.2.2,
transcribe the hourly temperatures occurring on those
dates according to the Local Climatological Data Monthly
Summary.
The hourly temperatures are located on pages 2 and 3 of
the Summary. Use the column labeled "Air °F".
Observations are listed at 3-hour intervals. Use linear
interpolation to fill in the missing hours.
2C.2.5 Calculate the average temperature during the 8-hour period
that the carbon monoxide exceedence occurred. This is the
exceedence temperature.
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2-85
2C.2.6 Calculate the average exceedence temperature occurring on
the 10 highest non-overlapping 8-hour carbon monoxide
concentration dates listed in 2C.2.2. Use this average
exceedence temperature as the value of ambient temperature
used in the Scenario descriptive input record of MOBILE4
(see section 2.3.4).
2C.2.7 When modeling carbon monoxide emissions only, use this
same temperature as the value of both minimum and maximum
daily temperature (see section 2.2.11), and set the value
of TEMFLG = 2 in the Control data section.
2C.3 LIST OF SUGGESTED LOCAL CLIMATOLOGICAL DATA STATIONS
FOR DETERMINING TEMPERATURES FOR USE IN MOBILE4
Table 2C.3-1 lists suggested climatological data stations for
use in determining appropriate temperatures in accordance with the
guidance provided above, for selected non-attainment areas.
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Tabled 2C.3-1
Suggested Local Climatological Data Stations for
Use in Determining Temperatures, for Selected
Ozone and Carbon Monoxide Non-Attainment Areas
AREA
ALLENTOWN-BETHLEHEM PA
ATLANTA GA
ATLANTIC CITY NJ
BAKERSFIELD CA
BALTIMORE MD
BATON ROUGE LA
BEAUMONT-PORT ARTHUR TX
Metro BOSTON MA
CHARLOTTE-GASTONIA NC
Metro CHICAGO IL
Metro CINCINNATI OH
Metro CLEVELAND OH
DALLAS-FORT WORTH TX
DENVER-BOULDER CO
EL PASO TX
FRESNO CA
GREATER CONNECTICUT
Metro Area
Metro HOUSTON TX
HUNTINGTON-
ASHLAND WV-KY-OH
INDIANAPOLIS IN
JACKSONVILLE FL
KANSAS CITY MO
LAKE CHARLES LA
LEXINGTON-FRANKFORT KY
LONGVIEW-MARSHALL TX
LOS ANGELES CA
LOUISVILLE KY
MEMPHIS TN
Metro MIAMI FL
Metro MILWAUKEE WI
MODESTO CA
MUSKEGON MI
NASHVILLE TN
NEW BEDFORD MA
Metro NEW YORK CITY NY
LOCAL CLIMATOLOGICAL DATA STATION(S)
ALLENTOWN, PA
ATLANTA, GA
Average of ATLANTIC CITY AP, ATLANTIC
CITY STATE MARINA
BAKERSFIELD, CA
BALTIMORE, MD
BATON ROUGE, LA
PORT ARTHUR, TX
BOSTON, MA
CHARLOTTE, NC
CHICAGO O'HARE AP
CINCINNATI, OH
Average of (CLEVELAND OH, AKRON-CANTON OH)
DALLAS-FT WORTH, TX
DENVER, CO
EL PASO, TX
FRESNO, CA
HARTFORD, CT
Average of HOUSTON TX, GALVESTON TX
HUNTINGTON, WV
INDIANAPOLIS, IN
JACKSONVILLE, FL
Average of KANSAS CITY INT'L AP, KANSAS
CITY DOWNTOWN AP
LAKE CHARLES, LA
LEXINGTON, KY
SHREVEPORT, LA
Average of LOS ANGELES AP, LOS ANGELES
CO, LONG BEACH
LOUISVILLE, KY
MEMPHIS, TN
MIAMI, FL
MILWAUKEE, WI
STOCKTON, CA
MUSKEGON, MI
NASHVILLE, TN
PROVIDENCE, RI
Average of NEW YORK CENTRAL PARK, NY JOHN
F. KENNEDY INT'L AP, NY LAGUARDIA FIELD,
NEWARK NJ, BRIDGEPORT CT
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2-87
Tabled 2C.3-1 (continued)
Suggested Local Climatological Data Stations for
Use in Determining Temperatures, for Selected
Ozone and Carbon Monoxide Non-Attainment Areas
AREA
Metro PHILADELPHIA PA
PHOENIX AZ
PORTLAND ME
PORTLAND OR
PORTSMOUTH-DOVER NH
PROVIDENCE RI
SACRAMENTO CA
SALT LAKE CITY UT
SAN DIEGO CA
SAN FRANCISCO CA
SANTA BARBARA CA
ST. LOUIS MO
STOCKTON CA
TAMPA-ST.
PETERSBURG FL
TULSA OK
VISALIA-TULARE CA
WASHINGTON DC
WORCESTER MA
YUBA CITY CA
LOCAL CLIMATOLOGICAL DATA STATION(S)
Average of PHILADELPHIA PA, WILMINGTON DE
PHOENIX, AZ
PORTLAND, ME
PORTLAND, OR
Average of PORTLAND ME, CONCORD NH
PROVIDENCE, RI
SACRAMENTO, CA
SALT LAKE CITY, UT
SAN DIEGO, CA
Average of SAN FRANCISCO AP, SAN FRANCISCO
CO
Average of SANTA BARBARA CA, SANTA MARIA CA
ST. LOUIS, MO
STOCKTON, CA
TAMPA, FL
TULSA, OK
FRESNO, CA
WASHINGTON NATIONAL AP
WORCESTER, MA
SACRAMENTO, CA
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Chapter 3
MOBILES OUTPUTS
3.0 INTRODUCTION
MOBILE4 produces three types of output: prompting messages,
diagnostic messages, and formatted reports.
Prompting messages are available from MOBILE4 if the user
selects PROMPT = 2 or 4 (section 2.1.1). These messages prompt
the user to provide MOBILE4 input data in the proper sequence.
There are two prompting formats: vertical flag input (PROMPT = 2)
and horizontal flag input (PROMPT = 4). Otherwise the prompting
messages are identical in both cases. Prompting messages are
discussed in section 3.1.
Diagnostic messages are used to caution the user concerning
user-supplied data. Three types of diagnostics exist: errors,
warnings, and comments. An error will in all cases terminate
processing of the current scenario, and in some cases will
terminate processing of the entire run. Warnings and comments are
included to assist users in the interpretation of the results of
MOBILE4. Diagnostic messages are discussed in section 3.2.
Four types of formatted reports can be produced by MOBILE4.
These reports include the information necessary to identify the
scenario being studied and the calculated emission factors by
vehicle type. The type of formatted report produced is controlled
by the value assigned to the OUTFMT flag in the Control section
(section 2.1.15). The structure of the formatted report formats
are discussed in section 3.3, and each is illustrated in Chapter 5
(MOBILE4 Examples).
3.1 PROMPTING MESSAGES
If PROMPT = 2 or 4, the user is prompted for input data in
the order required by MOBILE4. Prompting messages are written to
logical I/O unit 6, unless the user reassigns the prompting
message unit through the IOUNEW flag (section 2.1.2). MOBILE4
does not prompt for the first record (PROMPT flag and IOUNEW unit
reassignment record), since the value of the PROMPT flag
determines whether or not prompting will occur.
The prompt for each record is described below. The prompting
messages are printed in boldface in this section. See the
referenced sections of Chapter 2 for detailed discussion of the
prompted values.
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3-2
3.1.1 Control Section Prompts
3.1.1.1 Title Record Prompt
The title record for the MOBILE4 run is prompted for by this
message:
Enter project id:
3.1.1.2 16 Remaining Flag Prompts
If PROMPT = 2 (vertical format), the 16 remaining Control '
section flags are prompted for individually, as follows:
Enter TAMFLG:
Enter SPDFLG:
Enter VMFLAG:
Enter MYMRFG:
Enter NEWFLG:
Enter IMFLAG:
Enter ALHFLG:
Enter ATPFLG:
Enter RLFLAG:
Enter LOCFLG:
Enter TEMFLG:
Enter OUTFMT:
Enter PRTFLG:
Enter IDLFLG:
Enter NMHFLG:
Enter HCFLAG:
If PROMPT = 4 (horizontal format), the 16 remaining Control
section flags are prompted for on one record, with this message:
Enter TAMFLG, SPDFLG, VMFLAG, MYMRFG, NEWFLG, IMFLAG, ALHFLG, ATPFLG,
RLFLAG, LOCFLG, TEMFLG, OUTFMT, PRTFLG, IDLFLG, NMHFLG, & HCFLAG
3.1.2 One-time Data Section Prompts
Prompts for the One-time Data section inputs have been
extensively updated to correspond to MOBILE4 input requirements.
All of the possible prompts for data in the One-time Data section
are presented below.
-------
3-3
3.1.2.1 Tampering Rate Prompts
If TAMFLG=2, the replacement zero-mile tampering rates
(ZMLTAM) and increases in tampering with accumulated mileage, or
tampering rate deterioration rates (DRTAM) are asked for by one of
two possible pairs of prompts, depending on whether an inspection
and maintenance (I/M) program is to be assumed (see section 2.1.9).
The input requirements are discussed in section 2.2.1. If
IMFLAG = 1, then these prompting messages are used:
Enter tampering intercepts (zero-mile levels) for
non-l/M case only:
Enter tampering slopes (deterioration rates) for non-l/M
case only:
If IMFLAG = 2, then these prompting messages are used:
Enter tampering intercepts (zero-mile levels) for
non-l/M and I/M cases:
Enter tampering slopes (deterioration rates) for non-l/M
and I/M cases:
3.1.2.2 VMT Mix Record Prompt
If VMFLAG = 3, the user must supply one alternate vehicle
miles travelled (VMT) mix record, which will be applied to all
scenarios of the MOBILE4 run. The input required is discussed in
section 2.2.2. This record is prompted for by the message:
Enter VMT split:
3.1.2.3 Annual Mileage Accumulation Rates and/or
Registration Distributions by Age Prompts
If MYMRFG = 2, the user must supply annual mileage
accumulation rates by age for each of eight vehicle types. If
MYMRFG = 3, the user must supply registration distributions by age
for each of eight vehicle types. If MYMRFG = 4, the user must
supply both, with the annual mileage accumulation rates preceding
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3-4
the registration distributions. The input requirements are
discussed in section 2.2.3. These records are prompted for with
the following messages (first block applicable to annual mileage
accumulations, second block to registration distributions):
Enter MYM ages 1-10 for LDGVs:
Enter MYM ages 11-20 for LDGVs:
Enter MYM ages 1-10 for LDGTIs
Enter MYM ages 11-20 for LDGTIs
Enter MYM ages 1-10 for LDGT2s
Enter MYM ages 11-20 for LDGT2s
Enter MYM ages 1-10 for HDGVs:
Enter MYM ages 11-20 for HDGVs:
Enter MYM ages 1-10 for LDDVs:
Enter MYM ages 11-20 for LDDVs:
Enter MYM ages 1-10 for LDDTs:
Enter MYM ages 11-20 for LDDTs:
Enter MYM ages 1-10 for HDDVs:
Enter MYM ages 11-20 for HDDVs:
Enter MYM ages 1-10 for MCs:
Enter MYM ages 11-20 for MCs:
Enter
Enter
Enter
Enter
Enter
Enter
Enter
Enter
Enter
Enter
Enter
Enter
Enter
Enter
Enter
Enter
MYR
MYR
MYR
MYR
MYR
MYR
MYR
MYR
MYR
MYR
MYR
MYR
MYR
MYR
MYR
MYR
ages
ages
ages
ages
ages
ages
ages
ages
ages
ages
ages
ages
ages
ages
ages
ages
1-10
11-20
1-10
11-20
1-10
11-20
1-10
11-20
1-10
11-20
1-10
11-20
1-10
11-20
1-10
11-20
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
LDGVs:
LDGVs:
LDGTIs
LDGTIs
LDGT2S
LDGT2S
HDGVs:
HDGVs:
LDDVs :
LDDVs :
LDDTs :
LDDTs :
HDDVs :
HDDVs :
MCs:
MCs:
3.1.2.4 Alternate BER Prompts
If NEWFLG = 2, the user must supply one or more alternate
basic emission rate (BER) records. The input requirements are
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3-5
discussed in section 2.2.4, and are summarized in Table 2.2-1.
These records are prompted for with the messages:
Enter no. of new e.f. intercept/slope pairs:
Enter region, veh. type, pollutant, first my,
last my, intercept, slope, & above 50K miles slope:
The second message is repeated as many times as required, based on
the number entered in response to the first prompt.
3.1.2.5 I/M Program Parameter Record Prompt
If IMFLAG = 2, the user must supply a record specifying the
characteristics of the inspection and maintenance (I/M) program to
be modeled. The imput requirements are discussed in section 2.2.5
and are summarized in Table 2.2-2. The twelve I/M parameters are
prompted for by this message:
Enter the I/M Program parameter record:
Program start year, stringency,
first and last model year getting benefits,
old tech waiver rate, new tech waiver rate,
complicance rate,
frequency of I/M inspection,
vehicle classes covered, test type,
flag for alternate I/M credits, Tech l&lI and Tech IV+,
the format is:
(4(I2,1X),2(F2.0,1X),F3.0,1X,I1,
1X, I1,1X,4M ,1X, 11 ,1X,2I1)
If the value of either or both of the flags for alternate I/M
credits (the last two items of the I/M program record) is 2, the
user must also supply alternate I/M credits to be read from
logical I/O unit 4. MOBILE4 does not issue prompting messages for
the I/M credit data from unit 4.
3.1.2.6 ATP Parameter Record Prompt
If ATPFLG = 2, the user must supply a record specifying the
characteristics of the anti-tampering program (ATP) to be
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3-6
modeled. The input requirements are discussed in section 2.2.6
and are summarized in Table 2.2-3. The eight ATP parameters are
prompted for by this message:
Enter ATP start year, first & last years included
vehicle types covered, inspection type & frequency,
compliance rate, and inspections conducted (format =
3(I2,1X),4M,1X,2M,1X,F4.0,1X,8M):
Note that in MOBILE4 the user no longer supplies ATP emission
reduction credit matrices to be read from logical I/O unit 3.
MOBILE4 contains a subroutine that generates these credit matrices
on the basis of the information supplied characterizing the ATP.
3.1.2.7 VRS Descriptive Record Prompt
If RLFLAG = 2, 3, or 4, the user must supply one or two
records describing the refueling vapor recovery system (VRS)
requirements to be modeled. The Stage II VRS record is required
if RLFLAG = 2. The onboard VRS record is required if RLFLAG = 3.
Both records are required if RLFLAG = 4, with the Stage II record
preceding the onboard record. The input requirements are
discussed in section 2.2.7 and are summarized in Table 2.2-4. The
required record(s) are prompted for by one or both of these
messages:
Enter Stage I I VRS parameters -
start year, # phase-in years, LOG & HDG % efficiency:
Enter onboard VRS first model year & vehicle classes
(I2,1X,4M):
3.1.2.8 LAP Record Prompt
If LOCFLG = 2, the user must supply the local area parameter
(LAP) record as part of the One-time data section, and it will be
applied to all scenarios of the MOBILE4 run. Sections 2.2.8 -
2.2.13 discuss the input requirements, which are summarized in
Table 2.2-5. The LAP record is prompted for by this message:
Enter scenario name, ASTM class, min & max daily temps,
base & in-use RVP, in-use start year:
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3-7
3.1.3 Scenario Section Data Prompts
As discussed in section 2.3, the Scenario section consists of
one to four records, depending on the values assigned to flags in
the Control section. The first record, called the scenario
descriptive record, is mandatory. The second, third, and fourth
records are optional. All of the possible data prompting messages
for the Scenario data section are presented below.
3.1.3.1 Scenario Descriptive Record Prompt
The scenario descriptive record specifies the region,
calendar year of evaluation, average speed(s), ambient
temperature, and operating mode fractions to be assumed for the
current scenario. The input requirements are discussed in
sections 2.3.1 - 2.3.5, and are summarized in Table 2.3-1.
If SPDFLG = 1, a single value of average speed is used for
all vehicle types, and the record is prompted for by this message:
Enter region, CY, SPD(1), AMBT, PCCN, PCHC, PCCC:
If SPDFLG = 2, eight average speeds must be input, one for
each of the eight modeled vehicle types. The record is prompted
for with this message:
Enter region, CY, SPD(8), AMBT, PCCN, PCHC, PCCC:
3.1.3.2 LAP Record Prompt
If LOCFLG = 1, a distinct local area parameter record must be
supplied by the user for each scenario of the run. The input
requirements are discussed in sections 2.2.8 - 2.2.13, and are
summarized in Table 2.2-5. The LAP record for the current
scenario is prompted for by this message:
Enter scenario name, ASTM class, min & max daily temps,
base & in-use RVP, in-use start year:
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3-8
3.1.3.3 VMT Mix Record Prompt
If VMFLAG = 2, a distinct VMT mix record must be supplied by
the user for each scenario of the run. The input requirements are
discussed in section 2.2.2. The VMT mix for the current scenario
is prompted for by this message:
Enter VMT split:
3.1.3.4 Additional Light-Duty Correction Factor Record Prompt
If ALHFLG = 2 or 3, the user must supply a record used to
develop and apply up to four additional correction factors to the
light-duty gasoline-fueled vehicle and truck emission factors.
The input requirements are discussed in section 2.3.8 and are
summarized in Table 2.3-1.
If ALHFLG = 2, six input values are required, and are
prompted for with this message:
Enter AC, XLOAD(3), TRAILR(I), ABSHUM:
If ALHFLG = 3, ten input values are required, and are
prompted for with this message:
Enter AC, XLOAD(3), TRAILRC3), ABSHUM, DB, WB:
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3-9
3.2 DIAGNOSTIC MESSAGES
3.2.1 Introduction
This section describes the MOBILE4 diagnostic messages.
MOBILE4 issues three types of diagnostic messages: error
messages, warning messages, and comments.
Error messages indicate either that invalid input data were
entered into MOBILE4, or that MOBILE4 attempted to perform invalid
operations. All error messages are prefixed by "*** Error:".
If a number follows "*** Error:," it is the value read by
MOBILE4 for the variable in error (the variable name is also
printed) . If the error message is due to an input value that is
out of bounds, the range of acceptable values is also printed. An
error will stop a MOBILE4 run.
The following errors are considered to be "fatal" errors. If
any of these errors occur, no further processing of the MOBILE4
input data will be performed:
M28, M53, M60, M61, M82, M88, M89, M97, M107.
Warning messages indicate that MOBILE4 input data caused an
operation not necessarily intended by the user. However, the
situation is not serious enough to be labeled an error, and thus
warnings will not terminate execution of the program. Users
should carefully examine any warning messages issued by MOBILE4 to
ascertain the accuracy of the conditions that were modeled.
Comments are a type of warning message that are printed for the
user's information. Neither warning nor comment messages will
stop a MOBILE4 run.
The following is a list of the individual error, warning, and
comment messages. In order to make the listing more useful to the
MOBILE4 user, all of the messages are listed by message number
(M## at the beginning of each message). MOBILE4 has been
revised to print the message number as part of all diagnostic
messages, allowing the user to quickly look up the message and its
explanation in this section. The diagnostic messages are all
printed in boldface in this section.
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3-10
3.2.2 Explanation of Messages, Listed by Number (Mtttt)
M 1-M 16:
M ## *** Error: out of bounds for flag
One or more of these messages is printed preceding message M53 and
program termination. It will appear for each of the 16 input/
output control flags which is in error. The number appearing
after "*** Error:" is the value of the flag read by the program.
Each of these messages indicates the value falls outside of the
valid bounds for that flag. Allowable flag values are listed in
Tables 2.1-1 and 2.1-2. See section 2.1.
M 17 *** Error: out of bounds for VMTMIX
(0. to 1.)
This message is printed if a value of VMTMIX(IV) (vehicle miles
travelled fraction for vehicle type IV) is not between 0. and 1.
See Section 2.2.2.
M is *** Error: sum of VMTMIX is not equal to 1.
This message is printed if the sum of VMTMIX(IV) over all vehicle
types is not equal to 1. Since each VMTMIX(IV) represents the
fraction of total miles that vehicle type IV contributes to the
total vehicle miles traveled by the fleet, the sum of these
fractions should egual 1. See Section 2.2.2.
M 19 *** Error: negative model year mileage
This message is printed if the user supplied mileage accrual data
(annual mileage accumulation rate) for model year JDX and vehicle
type IV is negative. All annual mileage accumulation rates must
be > 0.0. See Section 2.2.3.
M 20 *** Error: negative model year
registrat ion
This message is printed if the registration fraction for vehicle
type IV vehicles of model year JDX is negative. Since this number
represents the fraction of all vehicles in the fleet of a given
age, it must be between 0. and 1. inclusive. See Section 2.2.3.
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3-11
M 21 Warning: registration with zero mileage
M 22 Warning: mileage with zero registration
One of these messages is printed if, for a given vehicle age,
vehicles of a given type either do not accumulate mileage yet make
up a fraction of the fleet (M21), or do not make up a fraction of
the fleet but accumulate mileage (M22). All vehicle type/model
year combinations assumed to exist in the fleet must accumulate
some mileage annually. For a given vehicle type and vehicle age,
if either the mileage accumulation rate or the registration
fraction is zero, both should be zero. See Section 2.2.3.
M 23 *** Error: out of bounds for e.f. changes
(1 to 100 pairs)
This message is printed if the number of emission rate
modifications is not between 1 and 100. MOBILE4 is limited to
handle a maximum of 100 modifications. See Table 2.2-1 and
section 2.2.4.
M 24 *** Error: out of bounds for region (1 or 2)
This message is printed if the region chosen in the scenario
record is not equal to 1 or 2. See section 2.3.1.
M 25 *** Error: out of bounds for vehicle type
(1 to 8)
This message is printed if the vehicle type in the basic emission
rate modification section is not 1, 2, 3, 4, 5, 6, 7, or 8. The
eight vehicle types in MOBILE4 and their corresponding codes are:
l = light-duty gasoline-fueled vehicles (LDGVs)
2 = light-duty gasoline-fueled trucks I (0-6000 Ibs GVW) (LDGTls)
3 = LDGTs II (6001-8500 Ibs GVW) (LDGT2s)
4 = heavy-duty gasoline-fueled vehicles (8501 + Ibs GVW) (HDGVs)
5 = light-duty diesel-powered vehicles (LDDVs)
6 = light-duty diesel-powered trucks (0-8500 Ibs GVW) (LDDTs)
7 = heavy-duty diesel-powered vehicles (8501 + Ibs GVW) (HDDVs)
8 = motorcycles (MCs).
See Table 2.2-1 and section 2.2.4.
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3-12
M 26 *** Error: out of bounds for pollutant
(1 to 3)
This message is printed if the code for pollutant on the emission
rate modification input section is not equal to 1, 2, or 3.
MOBILE4 considers only 1 = hydrocarbons, 2 = carbon monoxide, and
3 = oxides of nitrogen. See Table 2.2-1 and section 2.2.4.
M 27 *** Error: out of bounds for year
(1941 to 2020)
This message is printed if the code corresponding to the first or
last model year to have altered emission rates is not between 41
and 99 or 00 and 20 (corresponding to years 1941-2020). See Table
2.2-1 and section 2.2.4.
M 28 *** Error: Excess data errors prevent further analysis.
This message is printed if the accumulated number of data input
errors exceeds 50. The run is aborted at this point. All input
data should be thoroughly reviewed, and must be corrected before
rerunning the program.
M 29 *** Error: Last year cannot be less than first year
This message is printed if the first model year to have its
emission rates altered is less than (before) the last model year
to be altered. See Table 2.2-1 and section 2.2.4.
M 30 *** Error: intercept must be positive"
This message is printed if a new zero-mile emission level is <_ 0.
See Table 2.2-1 and section 2.2.4.
M 31 Warning: negative slope for ageing vehicle
This message is printed if the value for a new exhaust
deterioration rate is negative. A negative deterioration rate
implies improving emissions with increasing mileage accumulation.
See Table 2.2-1 and section 2.2.4.
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3-13
M 32 *** Error: out of bounds for year (1960 to
2020)
This message is printed if the code indicating the year in which
an I/M program is to begin does not fall between 60 and 99, or 00
and 20 (years 1960 to 2020). See Table 2.2-2 and sections 2.2.5
and 2A.1.2.
M 33 *** Error: out of bounds for stringency
(10 to 50)
This message is printed if the specified stringency of an I/M
program for 1980 and earlier LDVs or 1984 and earlier LDTs is not
between 10 and 50 (percent) inclusive. See Table 2.2-2 and
sections 2.2.5 and 2A.1.3.
M 34 *** Error: out of bounds for I/M Program
compliance rate (0 to 100%)
This message is printed if the specified value for compliance rate
of an I/M program is not between 0 and 100 (percent) inclusive.
See Table 2.2-2 and sections 2.2.5 and 2A.1.7.
M 35 *** Error: out of bounds for MODYR1 (1941
to 2020)
This message is printed if the code representing the first model
year under an I/M program is not between 41 and 99, or 00 and 20
(years 1941 to 2020). These years are the limits set by MOBILE4.
See Table 2.2-2 and sections 2.2.5 and 2A.1.4.
M 36 *** Error: out of bounds for MODYR2 (1941
to 2020)
This message is printed if the code representing the last model
year under an I/M program is not between 41 and 99, or 00 and 20
(years 1941 to 2020). These years are the limits set by MOBILE4.
See Table 2.2-2 and sections 2.2.5 and 2A.1.4.
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3-14
M 37 *** Error: MODYR1 cannot be greater than MODYR2
This message is printed if the first model year in an I/M program
is greater than the last model year in an I/M program. See Table
2.2-2 and sections 2.2.5, 2A.1.4, and 2A.1.5.
M 38 *** Error: out of bounds for year (1960 to 2020)
This message is printed if the calendar year to be evaluated is
not between 1960 and 2020 (60 to 99 or 00 to 20) inclusive. These
are the only years for which MOBILE4 evaluates emission factors.
See Table 2.3-1 and section 2.3.2.
M 39 *** Error: speed must be positive
This message is printed if the value of average speed (if
SPDFLG =1) or any of the eight values of average speed (if
SPDFLG = 2) is < 0.0. See section 2.3.3.
M 40 *** Error: valid ambient temperature is
0-110 deg (F)
This message is printed if the specified value for ambient
temperature value is not between 0° and 110°F. These are the
limits for application of temperature correction factors. See
section 2.3.4.
M 41 *** Error: out of bounds for PCCN (0. to 100.)
This message is printed if the input value for percentage of miles
traveled by non-catalyst vehicles in cold-start mode is not
between 0 and 100 (percent). See section 2.3.5.
M 42 *** Error:
-------
3-15
M 43 *** Error: out of bounds for PCCC (0. to
100.)
This message is printed if the input value for percentage of miles
traveled by catalyst-equipped vehicles in cold-start mode is not
between 0 and 100 (percent). See section 2.3.5.
M 44 *** Error: out of bounds for AC (0. to 1.)
This message is printed is the specified value for the fraction of
air-conditioner-eguipped vehicles actually using air conditioning
is not between 0. and 1. inclusive. See section 2.3.8.3.
M 45 *** Error: out of bounds for extra load
(0. to 1.)"
This message is printed if the specified fraction of vehicles
assumed to be carrying an extra 500 Ib load is not between 0. and
1. inclusive. See section 2.3.8.4.
M 46 *** Error: out of bounds for trailers
(0. to 1.)
This message is printed if the specified fraction of vehicles
assumed to be towing a trailer is not between 0. and 1.
inclusive. See section 2.3.8.5.
M 47 *** Error: out of bounds for humidity
(20. to 140.)
This message is printed is the specified value for absolute
humidity is not between 20 and 140 inclusive. See section 2.3.8.6.
M 48 *** Error: There are no sales for vehicle
MOBILE4 assumes that no significant number of LDDVs exist before
1975. Similarly, no significant number of LDDTs are assumed to
exist prior to 1978. This message is printed if the user inputs a
positive VMT fraction for LDDVs or LDDTs for calendar years in
which they are assumed to be virtually nonexistent.
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3-16
M 49 Warning: MYR sum not =1. (will normalize)
This message is printed if the sum of model year registration
fractions for a given vehicle type do not sum to 1. If the model
year age registration fractions do not sum to 1, MOBILE4
normalizes the fractions so that do sum to 1. See Section 2.2.3.
M so ***Error: out of bounds for tampering rate
intercept (up to 1.0)
The zero-mileage rate of tampering cannot exceed 100% of the fleet
(1.0 as a fraction) for any combination of tampering type and
vehicle type. See section 2.2.1.
M 51 *** Error: equation causes more than 12
allowed for any 1 reg/veh/pol
This message is printed if the user attempts to enter more than 12
modified basic emission rate equations for any one combination of
region, vehicle type, or pollutant. See section 2.2.4.
M 52 Warning: speed increased to 2.5 mph minimum
This message is printed if the average speed (SPDFLG = 1) or one
or more of the eight average speeds (SPDFLG = 2) is less than
2.5 mph. MOBILE4 increases the value to 2.5 mph and continues
execution. See section 2.3.3.
This message is printed if the specified average speed is < 2.5
mph. The speed correction factor equations are only valid for
speeds of 2.5 through 55 mph. See section 2.3.3.
M 53 Comment: All flags must be corrected before rerunning.
This message is printed if one or more errors occur in reading the
Control section flags. It should appear after a list indicating
which flags are in error (see M01-M16). The run is aborted at
this point. All flags in error must be corrected before the
program will continue.
-------
3-17
M 54 *** Error: End-of-file return on read of unit IOUIMD (new
FTP I/M credits. Run aborted.
M 55 *** Error: Error return on read of unit IOUIMD (new FTP I/M
credits. Run aborted.
These messages are printed if the user specifies alternate I/M
credits are to be read in from logical I/O device unit IOUIMD, and
the user either fails to supply the alternate credit data (M54) or
the alternate credit data contain errors (M55). Either of these
errors must be corrected before attempting to rerun the program.
M 56 Comment: A/C correction factor will be calculated.
Value of inputted AC usage parameter is ignored.
This message is printed if ALHFLG = 3 and a non-zero value for air
conditioning usage fraction is entered. With ALHFLG = 3, the air
conditioning usage fraction is calculated as a function of the
input dry bulb and wet bulb temperatures. See sections 2.3.8.3
and 2.3.8.7.
M 57 *** Error: WB temp cannot be greater than DB temp
This message is printed if the input wet bulb temperature is
greater than the input dry bulb temperature. The wet bulb
temperature is always less than or equal to the corresponding dry
bulb temperature. See section 2.3.8.7.
M 58 Warning: Average miles/day is zero for vehicle class and
model year
This message is printed is BLOCK DATA Subprogram 14 has been
incorrectly modified by the user.
M 59 Warning: equation zeroes all idle
coefficients (and total) for IR = , IV = , IP =
This message is printed when the user modifies the basic emission
rate equations for the specified region, vehicle type, and
pollutant. All alternative emission equations cause MOBILE4 to
zero all idle emission equations corresponding to the region,
vehicle type, and pollutant modified. See section 2.2.4.
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3-18
M 60 *** Error: exceeds ub of highest myg in
This message is printed to indicate that a default exit has been
taken from an index function. This message is generated by an
internal software error check, and should not occur unless the
program code has been damaged. The run is aborted at this point.
The program must be corrected and recompiled before another run.
M 61 *** Error: default used for in index function
This message is printed to indicate that a default exit has been
taken from an index function. One or more of the associated
year/years position pairs is in error. This message is generated
by an internal software error check, and should not occur unless
the program code has been damaged. The run is aborted at this
point. The program must be corrected and recompiled before
another run.
M 62 *** Error: out of bounds for new e.f.
region (1 or 2 only)
This message is printed if the region to which a modified basic
emission rate applies is specified to be other than 1
(low-altitude) or 2 (high-altitude). This specification of region
is independent of the region specified in the Scenario descriptive
record (see section 2.3.1). See Table 2.2-1 and section 2.2.4.
M 63 *** Error: < value of sum PCHC + PCCC> out of bounds
(0. <. PCHC + PCCC <. 100.)
This message is printed if the sum of the cold-start and hot-start
VMT percentages for catalyst-equipped vehicles is not between 0
and 100 percent inclusive. See section 2.3.5.
M 64 *** Error: out of bounds
(0. <_ PCHC + PCCC - PCCN <. 100.)"
This message is printed if the sum of the cold-start and hot-start
VMT percentages for catalyst-equipped vehicles less the cold-start
VMT percentage for non-catalyst vehicles is not between 0 and 100
percent inclusive. See section 2.3.5.
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3-19
M 65 *** Error: MYR of LDDV not equal to LDGV for JDX =
M 66 *** Error: MYR of LDDT not equal to LDGT1 for JDX =
One or both of these messages is printed if the user enters a
different registration distribution by age for LDGVs than for
LDDVs (M65) or for LDGTls than for LDDTs (M66). The registration
distribution by age for the total LDV (or LDT) fleet is to be
input twice for the gasoline-fueled and diesel vehicles (or
trucks). MOBILE4 apportions total registrations into the separate
gasoline-fueled and diesel groups based on diesel sales fractions
by model year. See section 2.2.3.4.
M 67 *** Error: EFFTP > 0. and GSF s 0. for vehicle
This message is printed if the named vehicle type has a positive
basic emission rate and a zero fleet sales fraction. See
section 2.2.3.
M 68 *** Error: EFFTP <. 0. AND VMTMIX > 0. for vehicle
This message is printed if no exhaust emission rates exist for the
named vehicle type, but vehicles of that type have accumulated a
nonzero fraction of the total vehicle fleet mileage.
M 69 *** Error: EFIDLE > 0. and GSF = 0. for vehicle 0. for vehicle
-------
3-20
M 71 Comment: Current output unit numbers are:
IOUREP = "formatted report unit"
IOUERR = "error/warning/comment unit"
IOUASK = "prompt message unit"
This message is printed whenever any of the default output unit
numbers are reassigned using the IOUNEW record in the Control
section. See section 2.1.2.
M 72 *** Error: out of bounds for I/M vehicle
type (1 to 2)
This message is printed if the value of ILDT(I) is not 1 or 2 in
the I/M program descriptive record. See Table 2.2-2.
M 73 *** Error: out of bounds for short test type
flag (1 to 3)
This message is printed if the value of ITEST (Technology IV+
short test type) is not l, 2 or 3. See Table 2.2-2.
M 74 *** Error: out of bounds for new I/M data
flag (1 or 2)
This message is printed if the value of the NUDATA flag (the flag
from the I/M program descriptive record indicating whether or not
new I/M credits are to be read from unit IOUIMD) is not 1 or 2.
See Table 2.2-2.
M 75 *** Error: out of bounds for anti-tampering
program start year
This message is printed if the value of the start year for the
selected anti-tampering program (ATP) is not in the range 1960 to
2020 (60 to 99 or 00 to 20). See Table 2.2-3 and section 2A.1.2.
M 76 *** Error: out of bounds for anti-tampering
program 1st model year
This message is printed if the value of the first model year
included in the selected ATP is not in the range 1941 to 2020
(41-99 or 00-20). See Table 2.2-3 and section 2A.1.4.
-------
3-21
M 77 *** Error: < value of LAPLST> out of bounds for anti-
tampering program last model year
This message is printed if the value of the last model year
included in the selected ATP is not in the range 1941 to 2020
(41-99 or 00-20). See Table 2.2-3 and section 2A.1.5.
M 73 *** error: out of bounds for anti-
tampering vehicle type (1 or 2)
This message is printed if the value entered for the ATP vehicle
class inclusion flag for vehicle type I is not either 1 (not
covered) or 2 (covered). See Table 2.2-3.
M 79 *** Error: < value of EVP> out of bounds for evap ATP
effectiveness rate (0. to 1.)
This message is printed if the value calculated for the
evaporative ATP effectiveness rate in the ATP effectiveness rate
matrices generated by MOBILE4 is not in the range 0.0 to 1.0.
These rates act as percentage credits, and hence must be
nonnegative and not exceed unity.
M 80 *** Error: < value of RATE> out of bounds for exh ATP
effectiveness rate (0. to 1.)
This message is printed if the value calculated for the exhaust
ATP effectiveness rate in the ATP effectiveness rate matrices
generated by MOBILE4 is not in the range 0.0 to 1.0. These rates
act as percentage credits, and hence must be nonnegative and not
exceed unity.
M 81 *** Error: out of bounds for AER matrix
file column sum (0. to 1.)"
This message is printed if any column of each of the 4 exhaust ATP
effectiveness rate matrices generated by MOBILE4 on the basis of
the ATP descriptive input record does not sum to a nonnegative
value not exceeding unity.
-------
3-22
M 82 *** Error: out of bounds for type of I/M
inspection (1 (centralized) or 2 (computerized decentralized) or
3 (manual decentralized))
This message is printed if the value of the I/M program type
specified in the I/M program descriptive record is not 1, 2, or 3.
The run is aborted at this point. See Table 2.2-2, and sections
2.2.5, 2A.1.12, 2A.1.13, and 2A.1.14.
M 83 Comment: One or more evaporative temperatures (input daily
maximum, input ambient, calculated hot soak, and/or calculated
running loss) is 40F or less, or the input daily minimum is 25F or
less; no evaporative emission factors (hot soak, diurnal, running
loss, or refueling) will be calculated.
This message is printed if (i) TEMFLG = 1 and one or more of the
temperatures calculated by MOBILE4 for correction of emissions, or
(ii) TEMFLG = 2 and the input ambient temperature, is less than or
equal to 40°F; or (iii) the input daily minimum temperature is
less than or equal to 25°F. See sections 2.1.13 and 2.2.11.5 for
additional information. The crankcase emissions will still be
calculated, resulting in a small non-zero evaporative emission
factor representing crankcase emissions only.
M 84 *** Error: out of bounds for onboard VRS
vehicle class flag (1 to 2)
This message is printed if the value of the IVOB flag for vehicle
type I indicating whether or not the vehicle type is subject to
the requirements of an onboard VRS system is not 1 or 2. See
Table 2.2-4 and section 2.2.7.
M 85 Message slot 85 is not assigned in MOBILE4.
M 86 *** Error: < value of NPHASE> out of bounds for no. of
stage II phase-in years (1 to 5)
This message is printed if the value of NPHASE in the Stage II VRS
descriptive record is not between 1 and 5. See Table 2.2-4 and
section 2.2.7.
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3-23
M 87 *** Error: out of bounds
for VRS or RVP controls start year
This message is printed if any of the specified start years for
Stage II VRS, onboard VRS, or in-use volatility (RVP) is not
between 1989 and 2020 (89-99 and 00-20). See sections 2.2.7 and
2.2.13.
M 88 *** Error: Message code unknown
This message should only be printed when the message printing
subroutine QUITER is passed an undefined message code value. The
run is aborted at this point.
M 89 *** Error: out of bounds for flag PROMPT.
This message is printed if PROMPT does not equal 1, 2, 3, or 4.
The run is aborted at this point, and this correction must be made
before the program will proceed. See section 2.1.1.
M 90 Warning: RVP is reset to
This message is printed if the input value for either base or
in-use RVP, or the value of either of these after fuel weathering
is accounted for, is outside of the input RVP limits of 7.0 to
15.2 psi inclusive; or, if the value of RVP to be used* in the
diurnal or hot soak evaporative emission factor calculation
exceeds an upper limit for each that depends on the temperature(s)
to be used in that calculation. See Table 2.2-5 and sections
2.2.12 and 2.2.13. The value printed first is reset by MOBILE4 to
before the emission factors are calculated.
M 91 *** Error: out of bounds for minimum daily
temperature
- or -
M 91 *** Error: out of bounds for maximum daily
temperature
One of these messages is printed if either the input minimum or
maximum daily temperature is outside the limits set by MOBILE4
(0 £ minimum <_ 100, 10 <^ maximum _< 120). See Table 2.2-5 and
section 2.2.11.
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3-24
M 92 *** Error: Max daily temp = < min daily
temp
This message is printed if the minimum daily temperature is
greater than the maximum daily temperature. See section 2.2.11.
M 93 Message slot 93 is not assigned in MOBILE4.
M 94 *** Error: out of bounds for ASTM
volatiIity Class (A-E)
This message is printed if a value other than one of the five
letters A/B/C/D/E is entered for the ASTM volatility class on the
local area parameter record. See Table 2.2-5 and section 2.2.10.
M 95 *** Error: Ambient temperature = is < daily
min temp or > daily max temp
This message is printed if the ambient temperature (see section
2.3.4) is either less than the minimum daily temperature or
greater than the maximum daily temperature (see section 2.2.11).
M 96 Warning: speed reduced to 55 mph maximum
This message is printed if the average speed (SPDFLG = 1) or one
or more of the eight average speeds (SPDFLG = 2) is greater than
55 mph. MOBILE4 reduces the value to 55 mph and continues
execution. See section 2.3.3.
M 97 *** Error: out of bounds for Wade Index
calculation (CALUDI) of A, pass < value of JV>: must be _> 0.0
This message is printed if an unrealistic combination of very high
fuel volatility (RVP) and temperature values are used in the
calculation of diurnal evaporative emissions. The run is aborted
at this point. Re-check all input RVP and temperature values.
See sections 2.2.11 - 2.2.13.
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3-25
M 98 Warning: Diurnal temperature rise (max temp - min temp =
) is > 40F; diurnal evaporative emission factors will be
calculated, but may be inaccurate.
This message is printed if the difference in the input daily
minimum and maximum temperatures is greater than 40 F° . See
section 2.2.11.5.
M 99 *** Error: out of bounds for Stage II
efficiency for LDGV (0 to 100%) or out of bounds
for Stage II efficiency for HDGV (0 to 100%)
This message is printed if the specified value for the efficiency
of Stage II VRS at controlling refueling emissions from LDGVs and
LDGTs, or from HDGVs, is not between 0 and 100 percent. See Table
2.2-4 and section 2.2.7.
M100 *** Error: out of bounds
for I/M Program waiver rate (0 to 50%)
This message is printed if the values specified for either waiver
rate for I/M programs on the I/M program descriptive record is not
between 0 and 50 percent inclusive. See Table 2.2-2 and sections
2.2.5 and 2A.1.6.
M101 *** Error: out of bounds for frequency of
I/M inspection (1 (annual) or 2 (biennial))
This message is printed if the value of IFREQ specified on the I/M
program descriptive record is not 1 or 2. See Table 2.2-2 and
sections 2.2.5 and 2A.1.8.
M102 Warning: High altitude I/M scenario requires user to supply
high altitude values for Tech 1&2 I/M credits arrays
This message is printed if the user specifies high-altitude as the
region for which emission factors are to be calculated and also
specifies that an I/M program is to be assumed. The I/M credits
contained in the MOBILE4 code are applicable only to low-altitude
regions. The MOBILE4 tape includes standard high-altitude region
I/M credit matrices, which must be read in on logical I/O unit 3.
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3-26
M103 *** Error: out of bounds for type of ATP
program (1 (centralized) to 2 (decentralized))
This message is printed if the value of the ATPPGM flag on the ATP
descriptive record, indicating the type of ATP to be modeled, is
not 1 or 2. See Table 2.2-3 and sections 2.2.6, 2A.1.12, 2A.1.13.
M104 *** Error: out of bounds for frequency of
ATP inspection (1 (annual) to 2 (biennial))
This message is printed if the value of the ATPFQT flag on the ATP
descriptive record, indicating the frequency of inspection in the
ATP to be modeled, is not 1 or 2. See Table 2.2-3 and sections
2.2.6 and 2A.1.8.
M105 *** Error: out of bounds for ATP compliance
rate, must be in the range 0.% to 100.%, inclusive
This message is printed if the specified ATP compliance rate is
not between 0 and 100 percent inclusive. See Table 2.2-3 and
sections 2.2.6 and 2A.1.7.
M106 *** Error: out of bounds for ATP
disablement inspections (1 (no) or 2 (yes))
This message is printed if the value of any of the eight DISTYP
flags on the ATP descriptive record, indicating whether or not
each of eight possible types of inspections are performed, is not
1 or 2. See Table 2.2-3, and sections 2.2.6 and 2A.2.3 through
2A.2.10.
M 107 *** Error: Error reading ATP program description in the
ONE-TIME data section
This message is printed if there is an error in reading the ATP
descriptive record. The run is aborted at this point. Check the
formats and all input values closely. See Table 2.2-3.
-------
3-27
M108 Warning: The ATP compliance rate of is not
equal to the I/M compliance rate of
This message is printed if the specified ATP compliance rate is
not equal to the specified I/M compliance rate. The program will
continue execution, but since such programs are generally run in
conjunction in a given area, the compliance rates generally should
be equal for both programs. See sections 2.2.5. 2.2.6, and 2A.1.7.
is
IFREQ>
M109 Warning: The ATP inspection frequency
and the I/M inspection frequency is , the
I/M inspection type is
This message is printed if the specified ATP program type (i.e.,
centralized or decentralized) is not the same as the specified I/M
program type. The program will continue execution, but since such
programs are generally run in conjunction in a given area, the
program type generally should be the same for both programs. See
sections 2.2.5. 2.2.6, 2A.1.12, and 2A.1.13.
Min *** Error: max daily temp
This message is printed if TEMFLG = 1 and one of the temperatures
calculated for correction of exhaust, evaporative, or running loss
emissions is outside of the range of the specified minimum and
maximum daily temperatures. Since these calculations use the
input minimum and maximum daily temperatures to start with, this
is an internal error check. If this message appears, and the
minimum and maximum daily temperatures are correct and meet all of
the necessary conditions, damage has occurred to either the source
code or the compiled program. Recompile and attempt the run again.
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3-28
3.3 FORMATTED REPORT OUTPUT
There are four different types of formatted report output.
The user specifies which of the four is to be generated through
assignment of a value to the OUTFMT flag in the Control section
(section 2.1.15). If OUTFMT = 1 or 2, MOBILE4 generates a
formatted data set suitable for use as an input file for
subsequent computer analysis ("numeric" output). If OUTFMT = 3
or 4, a report more suitable for visual inspection and analysis
("descriptive" format) is generated. These latter outputs are
designed to provide a well-annotated record of the user's analysis.
All four types of formatted report output have been revised
extensively since MOBILES to account for the numerous changes to
the model, its input requirements, and its output. Maintaining
compatibility of the MOBILE4 output files with those generated by
earlier versions of the emission factor model was not possible,
due to the many changes to both the input stream and the output
information. Thus, the user is advised to review the detailed
descriptions of each of the four output formats carefully,
particularly the numeric formats used as input for other models
and computer programs.
3.3.1 221-Column Numeric Format (OUTFMT = 1)
If OUTFMT = 1, the longest numeric format report is
generated. It consists of four heading records, which provide
minimal column descriptions, followed by one to ten records per
scenario evaluated. The number of records produced for each
scenario is determined by the values assigned to the PRTFLG,
IDLFLG, and HCFLAG flags in the Control section (sections 2.1.16,
17, 19).
Table 3.3-1 shows the number of records produced per scenario
evaluated and the content of the records, for each legitimate
combination of values of the PRTFLG, IDLFLG, and HCFLAG flags.
Each record of this output format consists of 35 subject
columns. (In the description that follows, the term "column" is
used to refer to the subject columns, while the term "character"
is used to refer to the number of individual, one-space columns
spanned by the subject column.) Example 1A in Chapter 5 is
illustrates this output format. The subject columns and the
value(s) shown in each are described below:
One other item to note with respect to the numeric output
formatted report options is the "carraige control" characters used
to control the placement of records. FORTRAN incorporates a
character in column 1 of each output record which is used to
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3-29
indicate carraige control (such as "start new page," "double-space
before printing next record," and similar instructions). If
OUTFMT = 1 or 2 and the formatted report is directed to a line
file, the first character space is reserved for this carraige
control character. Thus, all of the columns that follow in each
record are shifted one character space to the right:
Format Content
IX (carraige control character)
II (Column 1: Region)
IX,12 (Column 2: CY of evaluation), etc.
The total record length is then 221 columns (OUTFMT = 1) or 140
columns (OUTFMT =2).
If the numeric output formatted report is directed to a
printer, such as was done in generating examples la and Ib in
section 5.1.1, the instructions provided by the carraige control
characters are executed, but the characters are not printed and no
space is reserved for them on the hard copy. Thus, the format of
the printed version of OUTFMT = 1 or 2 reports does not begin with
IX (carraige control character), and the total length of each
record is 220 columns (OUTFMT = 1) or 139 columns (OUTFMT = 2).
Column 1: Region. The column is one character wide (format
II). The column heading is "Reg" (printed vertically). The value
shown is either 1 (low-altitude) or 2 (high-altitude). This
column contains values on all exhaust emission factor records, but
is blank for the component HC emission factor records. See
section 2.3.1.
Column 2: Calendar year of evaluation. The column is three
characters wide (format IX,12). The column heading is "CY". The
value shown is the last 2 digits of the calendar year of
evaluation. (Note that CY 2000 appears as "0", not "00".) This
column contains values on all exhaust emission factor records, but
is blank for the component HC emission factor records. See
section 2.3.2.
Columns 3-10: Vehicle Speeds. The column is 40 characters
wide (format 8F5.1). The column heading is "Vehicle Speeds". The
values shown are the average speeds used for each of the eight
vehicle classes, in this order: LDGV, LDGT1, LDGT2, HDGV, LDDV,
LDDT, HDDV, MC. If SPDFLG = 1, all eight speeds have the same
value. In print, the values are separated by slashes (/). For
example, if SPDFLG = 1 and speed =19.6 mph, this line appears:
19.6/19.6/19.6/19.6/19.6/19.6/19.6/19.6
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3-30
This column contains values on all exhaust emission factor
records, but is blank for the component HC emission factor
records. See section 2.3.3.
Column 11: Ambient Temperature. The column is four
characters wide (format IX,13). The column heading is "Amb Tern"
on two lines. The value(s) that appear in this column depend on
the value of TEMFLG: If TEMFLG = 1, the temperature(s) calculated
by MOBILE4 based on the input minimum and maximum daily
temperatures for the correction of exhaust HC, CO, and NOx
emission factors are printed on the applicable line. If
TEMFLG = 2, the input ambient temperature is echoed back on the
exhaust emission factor records. This column contains values on
all exhaust emission factor records, but is blank for the
component HC emission factor records (evaporative, refueling, and
running loss). See sections 2.1.14, 2.2.11, and 2.3.4.
Columns 12-14: Operating Mode Fractions. The column is 18
characters wide (format 3F6.1). The column heading is "Cold/Hot
Start". The values that appear are the input values for PCCN,
PCHC, and PCCC, in that order. This column contains values on all
exhaust emission factor records, but is blank for the component HC
emission factor records. See section 2.3.5.
Column 15: Altitude. The column is 7 characters wide
(format F7.0). The column heading is "Alt. in Ft." on two lines.
This feature is residual from earlier versions of the model. The
value that appears is either 500. (if the input region is 1 (low-
altitude)), or 5500. (if the input region is 2 (high-altitude)).
This column contains values on all exhaust emission factor
records, but is blank for the component HC emission factor records.
Column 16: Pollutant. The column is two characters wide
(format IX,Al). The column heading is "Pol" printed vertically.
The values and their corresponding identification of pollutants
are:
Value Pollutant Value Pollutant
1 Total HC X Exhaust HC
2 Exhaust CO V Evaporative HC
3 Exhaust NOx (includes crankcase)
4 Idle HC R Refueling HC
5 Idle CO T Running loss HC
6 Idle NOx
See sections 2.1.16, 2.1.17, 2.1.19, and Table 3.3-1.
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3-31
Columns 17-26: Composite Emission Factors. The next ten
columns are each eight characters wide (format 10F8.3). The
column headings are "Composite Emission Factors" centered over all
80 characters, with the individual columns headed in order by:
"LDGV", "LDGT1", "LDGT2", "LDGT", "HDGV", "LDDV", "LDDT", "HDDV",
"MC", and "All Veh". These represent the emission factors for the
pollutant identified in column 16, for the following vehicle
classes in order: light-duty gasoline-fueled vehicles, light-duty
gasoline-fueled trucks 1 (up to 6,000 Ibs), light-duty gasoline-
fueled trucks 2 (6,001-8,500 Ibs), all LDGTs together (weighted
results for LDGTls and LDGT2s), heavy-duty gasoline-fueled
vehicles (over 8,500 Ibs), light-duty diesel vehicles, light-duty
diesel trucks (up to 8,500 Ibs), heavy-duty diesel vehicles (over
8,500 Ibs), motorcycles, and all vehicles combined (weighted by
the VMT mix; see columns 27-34 below). The emission factors are
listed to 3 decimal places (0.001 g/mi) in this type of formatted
report.
Columns 27-34: VMT Mix. The next eight columns are each six
characters wide (format 8F6.3). The column headings are "Vehicle
Mix" centered over all 48 columns, with the individual columns
headed in order by: "LDGV", "LDGT1", "LDGT2", "HDGV", "LDDV",
"LDDT", "HDDV", and "MC". The values are the VMT mix input by the
user for the current scenario. This column contains values on all
exhaust emission factor records, but is blank for the component HC
emission factor records.
Column 35: Scenario Title. The column is 17 characters wide
(format 1X,4A4). The heading is "Scenario Title". The value is
the echo of the scenario title input as part of the Local Area
Parameter record. See sections 2.2.8 and 2.2.9, and Table,2.2-5.
3.3.2 140-Column Numeric Format (OUTFMT = 2)
If OUTFMT =2, a somewhat shorter numeric format report is
generated. As in the case of the longer 222-column numeric format
report, it consists of four heading records providing minimal
column descriptions, followed by one to ten records per scenario
evaluated. The number of records produced for each scenario is
determined by the values assigned to the PRTFLG, IDLFLG, and
HCFLAG flags in the Control section (sections 2.1.16, 17, 19).
Table 3.3-1 shows the number of records produced per scenario
evaluated and the content of the records, for each legitimate
combination of values of the PRTFLG, IDLFLG, and HCFLAG flags.
Each record of this output format consists of 25 subject
columns. (In the description that follows, the term "column" is
used to refer to the subject columns, while the term "character"
is used to refer to the number of individual, one-space columns
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3-32
spanned by the subject column.) Example Ib in Chapter 5
illustrates this output format. Note that this output will be
truncated after a maximum of 132 columns if printed in landscape
format on standard 8.5x11 inch paper unless wrapped around. See
the discussion of carraige control characters provided in section
3.1.1, which is also applicable in this case. The subject columns
and the value(s) shown in each are described below:
Column 1; Region. The column is one character wide (format
II). The column heading is "Reg" (printed vertically). The value
shown is either 1 (low-altitude) or 2 (high-altitude). This
column contains values on all exhaust emission factor records, but
is blank for the component HC emission factor records. See
section 2.3.1.
Column 2: Calendar year of evaluation. The column is three
characters wide (format IX,12). The column heading is "CY". The
value shown is the last 2 digits of the calendar year of
evaluation. (Note that CY 2000 appears as "0", not "00".) This
column contains values on all exhaust emission factor records, but
is blank for the component HC emission factor records. See
section 2.3.2.
Column 3: Ambient Temperature. The column is five
characters wide (format IX,13,IX). The column heading is "Amb
Tern" on two lines. The value(s) that appear in this column depend
on the value of TEMFLG: If TEMFLG = 1, the temperature(s)
calculated by MOBILE4 based on the input minimum and maximum daily
temperatures for the correction of exhaust HC, CO, and NOx
emission factors are printed on the applicable lines. If
TEMFLG = 2, the input ambient temperature is echoed back on the
exhaust emission factor records. This column contains values on
all exhaust emission factor records, but is blank for the
component HC emission factor records (evaporative, refueling, and
running loss). See sections 2.1.14, 2.2.11, and 2.3.4.
Columns 4-6: Operating Mode Fractions. The column is 18
characters wide (format 3F6.1). The column heading is "Cold/Hot
Start". The values that appear are the input values for PCCN,
PCHC, and PCCC, in that order. This column contains values on all
exhaust emission factor records, but is blank for the component HC
emission factor records. See section 2.3.5.
Column 7: Pollutant. The column is two characters wide
(format IX,Al). The column heading is "Pol" printed vertically.
The values and their corresponding identification of pollutants
are:
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Value Pollutant
1 Total HC
2 Exhaust CO
3 Exhaust NOx
4 Idle HC
5 Idle CO
6 Idle NOx
Value Pollutant
X Exhaust HC
V Evaporative HC
(includes crankcase)
R Refueling HC
T Running loss HC
See sections 2.1.16, 2.1.17, 2.1.19, and Table 3.3-1.
Columns 8-17: Composite Emission Factors. The next ten
columns are each eight characters wide (format 10F8.3). The
column headings are "Composite Emission Factors" centered over all
80 characters, with the individual columns headed in order by:
"LDGV", "LDGT1", "LDGT2", "LDGT", "HDGV", "LDDV", "LDDT", "HDDV",
"MC", and "AllVeh". These represent the emission factors for the
pollutant identified in column 7, for the following vehicle
classes in order: light-duty gasoline-fueled vehicles, light-duty
gasoline-fueled trucks 1 (up to 6,000 Ibs), light-duty gasoline-
fueled trucks 2 (6,001-8,500 Ibs), all LDGTs together (weighted
results for LDGTls and LDGT2s), heavy-duty gasoline-fueled
vehicles (over 8,500 Ibs), light-duty diesel vehicles, light-duty
diesel trucks (up to 8,500 Ibs), heavy-duty diesel vehicles (over
8,500 Ibs), motorcycles, and all vehicles combined (weighted by
the VMT mix; see columns 18-25 below). The emission factors are
listed to two decimal places (0.01 g/mi) in this type of formatted
report.
Columns 18-25: VMT Mix. The next eight columns are each six
characters wide (format 8F6.3). The column headings are "Vehicle
Mix" centered over all 48 columns, with the individual columns
headed in order by: "LDGV", "LDGT1", "LDGT2", "HDGV", "LDDV",
"LDDT", "HDDV", and "MC". The values are the VMT mix input by the
user for the current scenario. This column contains values on all
exhaust emission factor records, but is blank for the component HC
emission factor records.
3.3.3 112-Column Descriptive Format (OUTFMT = 3)
If OUTFMT = 3, a well-annotated descriptive format output is
produced. This format is designed for ease of visual inspection,
with more complete labeling and heading information. The
112-column width allows this format to be printed in landscape
format (sideways) on standard 8.5x11 paper.
The exact content of the report is determined by a number of
flag settings. Information applicable to the entire run (all
scenarios) is listed first, followed by a series of blocks, one
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per scenario evaluated. The scenario output blocks are separated
by solid lines.
Each possible component of this output format is briefly
described below. Example Ic in Chapter 5 is an illustration of
this type of output.
The first line of the report is the project title input by
the user (section 2.1.1). This is followed by a blank line, then
by the following optional information if applicable:
If the output units have not been reassigned (section 2.1.2),
then any diagnostic messages generated will follow the project
title.
If an I/M program is to be modeled (IMFLAG = 2), a block
echoing the descriptive information on the I/M program will be
printed. This block consists of 16 lines. For example:
I/M program selected:
Start year (January 1): 1981
Pre-1981 MYR stringency rate: 20%
First model year covered: 1965
Last model year covered: 2020
Waiver rate (pre-1981); 10.%
Waiver rate (1981 and newer): 10.%
Compliance rate: 80.%
Inspection type: Centralized
Inspection frequency: Annual
Vehicle types covered: LDGU - Yes
LDGT1 - Yes
LDGT2 - Yes
HDGV - No
1981 & later MYR test type: Idle
If the user has supplied alternate I/M credits, then a
message indicating this can be printed following this block. This
message must be provided in the alternate I/M credit file to be
read from logical I/O unit 4.
If the user has selected modeling of the effects of an anti-
tampering program (ATP), the program description is echoed. This
block consists of 19 lines. For example:
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Anti-tampering program selected:
Start year (January 1): 1981
First model year covered: 1970
Last model year covered: 2020
Vehicle types covered: LDGV
Type: Centralized
Frequency: Annual
Compliance Rate: 90.0%
Air pump system disablements: Yes
Catalyst removals: Yes
Fuel inlet restrictor disablements: Yes
Tailpipe lead deposit test: No
EGR disablements: Yes
Evaporative system disablements: Yes
PCV system disablements: Yes
Missing gas caps: No
If both I/M and anti-tampering programs are selected, the I/M
block precedes the ATP block in the output.
If alternate basic emission rates are modeled (NEWFLG = 2),
message M59 (see section 3.2.2) will be printed, followed by a
table summarizing the changes made to the BERs. For example:
Emission Factor Modification Profile
Equation Reg Veh Pol First MY Last MY Base PR 50K PR Altered
1 212 1980 1986 30.05 3.01 3.44 Yes
If one local area parameter record is to be applied to all
scenarios (LOCFLG = 2), this information is printed on the next
two lines. The first line lists the scenario name, ASTM class,
and minimum and maximum daily temperatures. The second line lists
the base RVP, in-use RVP, and in-use start year. Each of these is
clearly indicated with a label.
Finally, one of the following messages will be printed before
the individual scenario results. If NMHFLG = 1: "Total HC
emission factors include evaporative HC emission factors", and if
NMHFLG = 2: "Non-methane HC emission factors include evaporative
HC emission factors".
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3-36
The above information is followed by a series of scenario
output blocks, separated for each scenario by solid lines. Each
of these blocks has the same format and structure.
After the line indicating the start of a scenario output
block, the following one-line messages are printed if applicable
to that scenario:
If TAMFLG = 2:
"User supplied tampering and misfueling rates"
If MYMRFG = 2:
"User supplied mileage accrual distributions"
If MYMRFG = 3:
"User supplied veh registration distributions"
If MYMRFG = 4:
"User supplied mileage accrual distributions, veh
registration distributions"
These messages are followed by two lines describing the
secenario being modeled. The first line includes the calendar
year of evaluation, whether or not an I/M program is modeled, the
ambient temperatures used to correct exhaust HC, CO, and NOx
emissions, and the region (low- or high-altitude). The second
line includes whether or not an ATP is modeled, the operating mode
fractions, and the altitude (500 ft for low-altitude and 5500 ft
for high-altitude). Each of these is clearly labeled. The three
ambient temperatures apply, in order, to HC, CO, and NOx.
Two additional lines containing the local area parameter
record information follow, if LOCFLG = 1 (separate local area
parameter record for each scenario). The first line lists the
scenario name, ASTM class, and minimum and maximum daily
temperatures. The second line lists the base RVP, in-use RVP, and
in-use start year. Each of these is clearly indicated by a label.
The next line starts with "Veh. Type:" and continues across
with ten column headings. In order, these are LDGV, LDGT1, LDGT2,
LDGT, HDGV, LDDV, LDDT, HDDV, MC, and All Veh. The remaining
lines in the output each consist of an identifier at left, with
the values for that line, for each of the ten vehicle types or
groups, following under the appropriate headings.
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The next line is "Veh. Speeds:", with values entered only in
the eight columns for which vehicle average speed is used to
correct the emission factors. The next line is "VMT Mix:", with
VMT fractions by vehicle class entered in the appropriate
columns. (No speed or VMT Mix values will appear under the
combined LDGT1 and LDGT2 "LDGT" column or the "All Veh" column.)
The next line reads "Composite Emission Factors (Gm/Mile)".
This line precedes a set of one to seven lines of emission
factors, depending on the pollutants to be printed (PRTFLG) and
whether component HC emission factors are to be printed (HCFLAG).
If all seven lines appear, they are in the following order:
Label Content
Total HC: Total or Non-methane HC emission factor
(EF), including all components (whether
or not they are listed individually)
Exhaust HC: Exhaust HC component EF
Evaporat HC: Evaporative HC component EF (includes
crankcase emissions)
Refuel L HC: Refueling loss HC component EF
Runing L HC: Running loss HC component EF
Exhaust CO: Exhaust CO EF
Exhaust NOx: Exhaust NOx EF
Unless the idle emission factors have been requested, this
completes the block for an individiual scenario. If IDLFLG = 2,
indicating that idle emission factors are to be printed, the
following identifying line is printed: "Hot Stabilized Idle
Emission Factors (Gm/Hr)". This is followed by one to three
additional lines, depending on the pollutants to be listed. These
lines are labeled "Idle HC:", "Idle CO:", and "Idle NOx:".
3.3.4 80-Column Descriptive Format (OUTFMT = 4)
If OUTFMT =4, a well-annotated descriptive format output
similar to that described in section 3.3.3 is produced. This
format is also designed for ease of visual inspection, with
complete labeling and heading information. The 80-column width
allows this format to be printed in portrait format (vertically)
on standard 8.5x11 paper.
The exact content of the report is determined by a number of
flag settings. Information applicable to the entire run (all
scenarios) is listed first, followed by a series of blocks, one
per scenario evaluated. The scenario output blocks are separated
by solid lines. Example Id in Chapter 5 is an illustration of
this type of output.
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This output follows the order of information presented in
section 3.3.3 above, with additional lines and minor format
changes required in some cases to accomodate all of the
information in the narrower overall width. Refer to Example Id in
section 5.1.1 and the desciptions provided above.
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Table 3.3-1
Number and Content of Records per Scenario
(222-column and 140-column numeric output formats)
Flaq Values*
PRTFLG
1
1
1
1
2
2
3
3
4
4
4
4
IDLFLG
1
1
2
2
1
2
1
2
1
1
2
2
HCFLAG
1
2
1
2
1 * *
1**
1**
1* *
1
2
1
2
Records/
Scenario
1
5
2
6
1
2
1
2
3
7
6
10
Content (in order of
Total HC
Total HC, exhaust
evaporative (evap) HC,
HC, running loss HC
Total HC, idle HC
Total HC, exh HC,
refueling HC, running
idle HC
Exh CO
Exh CO, idle CO
Exh NOx
Exh NOx, idle NOx
listing)
(exh)
HC,
refueling
evap
loss
HC,
HC,
Total HC, exh CO, exh NOx
Total HC, exh HC,
refueling HC, running
exh CO; exh NOx
Total HC; exh CO; exh
HC; idle CO; idle NOx
Total HC, exh HC,
evap
loss
NOx;
evap
HC,
HC;
idle
HC,
refueling HC, running loss HC;
exh CO; exh NOx; idle HC; idle
CO; idle NOx
* PRTFLG: 1 = HC only, 2 = CO only, 3 = NOx only, 4 = HC, CO, & NOx
IDLFLG: 1 = No idle emission factors, 2 = include idle EFs
HCFLAG: 1 = Total HC only, 2 = Total and component HC EFs
** HCFLAG = 1 (do not print components of HC emission factor) is
mandatory if PRTFLG = 2 (CO only) or 3 (NOx only).
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Chapter 4
MOBILE4 IMPLEMENTATION
4.0 INTRODUCTION
This chapter contains information on the MOBILE4 tape, and
other information that may be useful to users interested in the
computer resource requirements of MOBILE4, to users implementing
MOBILE4 on their own computer systems, and to users who are
considering making software changes. It also contains
instructions on how to port the mainframe version of the code to
personal computers (Macintosh, and IBM PC-AT or clone).
4.1 MOBILE4 TAPE
The MOBILE4 tape released by EPA contains four files. The
first file is the MOBILE4 source code in mixed-case lettering
(upper and lower). The second file is exactly the same as the
first file, except it is an uppercase-only lettering version.
This second file has been provided in the event some systems have
difficulty with lowercase characters. The mixed-case version is
more easily read than the all-uppercase version.
The third file is a copy of the input files used to generate
the User's Guide examples of Chapter 5, in uppercase. These
examples can be used to verify that MOBILE4 is operating properly
when installed on a new system.
The fourth file on the tape is a set of standard parameter
inpsection and maintenance (I/M) program credits applicable to
high-altitude areas. The I/M credits stored in the MOBILE4 code
are applicable only to low-altitude areas. This file has the same
structure as is used for the credits contained in the code, but
for high-altitude areas. See section 2.2.5 and Appendix 2A.
Note that the file that contained anti-tampering program
credit matrices, which was included on the MOBILES tape, has no
counterpart on the MOBILE4 tape. This is because MOBILE4 has been
revised to include a subroutine that generates the necessary
credit matrices on the basis of the ATP descriptive information
provided by the user. See section 2.2.6 and Appendix 2A.
Other characteristics of the MOBILE4 tape are presented in
Table 4.1-1.
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Table 4.1-1
MOBILE4 Tape Characteristics
Density: 1600 bpi Character Set: EBCDIC
Blocking: 4000 Total Length: 168.33 feet
Record Length: 80 Unlabeled
File Number of Block Tape Length
Number Description Records Count (Feet)
1 MOBILE4 Source Code 21,296 426 112.17
(Mixed-case letters)
*
2 MOBILE4 Source Code 21,296 426 112.17
(Uppercase)
3 Input Files for
User's Guide Examples 207 5 1.45
4 I/M Credit Matrices 406 9 2.49
(for high-altitude areas)
4.2 PROGRAM STORAGE REQUIREMENTS
The wide variety of computers and system configurations in
use prohibits a precise statement of main storage requirements on
each system. Nevertheless, the following should be representative
of the requirements of MOBILE4 on most systems.
Kilobytes 32-bit memory words
Source Code 920 235,520
Object Code 608 155,648
The standard convention of 1 kilobyte = 1024 bytes is used.
The values were obtained from the implementation of MOBILE4 on the
Michigan Terminal System at Wayne State University, based on an
Amdahl 5890-180E computer.
4.3 PROGRAM EXECUTION TIME
MOBILE4 requires more time to process scenario records than
does MOBILES. This was expected due to the extensive revisions
made to the program, including the additions of many subroutines
and the increased complexity of many of the computational
algorithms used. Table 4.3-1 provides a comparison of the
execution time required by MOBILE4 and MOBILES to process input
data containing varying numbers of scenarios.
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Table 4.3-1
Comparison of MOBILE4 and
MOBILES Execution Times
Average Average
Execution Time Time per Scenario
Number of (CPU Seconds) Ratio (CPU Seconds)
Scenarios MOBILE4 MOBILES (M4/M3) MOBILE4 MOBILES
1 0.089 0.068 1.31 0.089 0.068
2 0.162 0.123 1.32 0.081 0.062
10 0.756 0.565 1.34 0.076 0.057
20 1.495 1.115 1.34 0.075 0.056
50 3.693 2.760 1.34 0.074 0.055
250 18.546 13.751 1.35 0.074 0.055
The MOBILE4 flag settings used for these execution timing
runs are identical to those of Example 1 in Chapter 5. To the
extent possible, the same or equivalent settings were used for the
MOBILES runs (the considerable changes between MOBILES and MOBILE4
prevent direct comparison of precisely the same scenarios). The
second scenario of Example 1 (CY of evaluation 1988) was executed
the indicated number of times. These estimates were results from
runs executed on an Amdahl 5890-180E computer. The average time
per scenario statistic equals total execution time divided by the
number of scenarios.
4.4 DEVIATIONS FROM FORTRAN STANDARD ANSI X3.9-1978
The previous version of the emission factor model, MOBILES,
was based on the FORTRAN language standard ANSI X3.9-1966
published by the American National Standards Institute. However,
there were a number of incompatibilities between the FORTRAN code
used in MOBILES and the ANSI X3.9-1966 standards. MOBILE4 has
been updated to reflect the ANSI X3.9-1978 FORTRAN standards, and
no incompatibilities are known to exist between the MOBILE4 code
and that standard.
4.5 TYPICAL JOB STRUCTURE
Since job control language (JCL) is highly system-dependent,
this manual does not provide examples. The general requirements
for running a job are outlined here. Most users should have
little difficulty implementing JCL to perform similar functions.
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4-4
The simplest job structure for most systems is shown below:
JCL to sign on the computer system
JCL to compile MOBILE4 FORTRAN source code
(MOBILE4 FORTRAN source code)
JCL to assign MOBILE4 I/O, catalog (link edit), and run MOBILE4
(MOBILE4 input data)
MOBILE4 uses I/O device numbers stored in common IOUCOM.
MOBILE4 I/O device assignments are:
4 = user-supplied inspection/maintenance (I/M) credits (IOUIMD)
5 = general input data (IOUGEN)
6 = formatted reports (IOUREP)
6 = diagnostic messages (IOUERR)
6 = input prompting messages (IOUASK)
Users can change these device numbers by modifying source
code data statements initializing common IOUCOM in Block Data
Subprogram 16. Output devices only can also be changed by
assigning replacement numbers to IOUNEW on line 1 of the Control
data section, as disucussed in section 2.1.2.
The job structure illustrated above does not read user-
supplied I/M credits. Users can read I/M credits by entering the
data from another I/O device, such as a disk file or magnetic
tape. Alternately, users can merge the credits or rates with
other input and change the I/M logical I/O device number from 4
to 5 by revising BLOCK DATA Subprogram 16 (line 516076);
change DATA IOUIMD,IOUGEN,IOUERR,IOUASK/4,5,6,2*9/
to DATA IOUIMD,IOUGEN,IOUERR,IOUASK/5,5,6,2*9/.
Another useful change (especially for OUTFMT = 1 or 2) might alter
IOUREP from 6 to some other unused unit number via IOUNEW. Again,
see section 2.1.2.
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4-5
4.6 INSTALLATION, COMPILING, AND EXECUTION
OF MOBILE4 ON PERSONAL COMPUTER SYSTEMS
4.6.1 Introduction
Due to the increased utilization of personal computers (PCs)
by many parties involved in emission factor modeling and air
quality planning functions, EPA has developed MOBILE4 so as to be
compatible to the greatest extent possible with the two most
commonly used PC systems: Apple Macintosh, and IBM PC-AT (and its
clones). However, since the development of the program was
performed entirely on mainframe time-sharing systems, some
differences exist between the MOBILE4 program as developed and
discussed in this User' s Guide, and the program in a form that can
be executed on PC systems. This section provides instructions for
installing, compiling, and executing MOBILE4 on the PCs mentioned.
4.6.2 Installing, Compiling, and Executing
MOBILE4 on an Apple Macintosh PC
The directions provided in this section assume that the
Macintosh being used has 512K bytes of free memory, a hard disk
drive, and ABSOFT Corporation's MacFORTRAN or MacFORTRAN/020
compiler.
The first operation necessary is to port the MOBILE4 source
code to the Macintosh unit. To accomplish this transfer, an
error-checking protocol (such as KERMIT) should be used. The
MOBILE4 code should be transmitted so that an ASCII text file,
with no hidden characters (such as tabs), is created.
Once transferred, the code must be modified slightly to
accomodate the Macintosh FORTRAN environment. These required
modifications include file opening statements and screen/keyboard
connections:
1. Insert the following lines controlling file I/O just
before the statement INERR=0 (line 1176) in the MOBILE4 MAIN
program section:
OPEN(5,FILE='M4INPUT',STATUS='OLD')
OPEN(6,FILE='M40UTPUT',STATUS='NEW')
2. If alternate I/M credits are also to be read in (see
section 2.2.5), then insert the following line immediately after
the statement IFCNONUDA.EQ.2) GOTO 60 (line 115037) in
Subroutine GETIMC:
OPEN(4,FILE='M4IMC',STATUS=OLD)
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4-6
3. Finally, alter the initialization line for screen/keyboard
I/O in BLOCK DATA Subprogram 16 (line 516076) to read:
DATA IOUIMD,IOUGEN,IOUERR,IOUASK/4,5,6,2*9/
These changes direct MOBILE4 to always read the program input
from a file called M4INPUT, and to always write the program output
to a file called M40UTPUT. Similarly, if the alternate I/M credit
data modification was made, then the alternate credits will always
be read from a file called M4IMC. Lastly, the initialization
change directs all prompting or diagnostic messages to the
Macintosh screen (logical I/O device unit 9).
After these changes have been made, invoke the compiler. If
your Macintosh unit has a math coprocessor, select it using the
OPTIONS menu.
When the compilation has been completed, the heap space for
the resulting MOBILE4 application must be adjusted. To do this,
click on the MOBILE4 application icon one time, then select the
FILE option from the Macintosh FINDER menu (not the compiler's
menu). Highlight the GET INFO item, and note the application size
value in the lower right portion of the window. If it is less
than 512K, increase it to 512K. The MOBILE4 application is now
ready for use.
Before running the program, place the MOBILE4 input stream
(see Chapter 2) in a file called M4INPUT. Next, check to be sure
that the M40UTPUT file is empty. (If M4OUTPUT contains data or
information you wish to save, simply rename it so that it is not
overwritten by the results of the pending MOBILE4 run.) To
execute, launch the MOBILE4 application by double-clicking its
icon.
4.6.3 Installing, Compiling, and Executing
MOBILE4 on an IBM PC-AT (or clone)
Due to the size of the MOBILE4 source code and the number of
variables, common blocks, and other data structures contained in
the program, the MOBILE4 code cannot be ported to these systems as
easily as described above. While porting of the code to IBM
PC-ATs (or clones) is possible, it is a more complicated
procedure. For assistance in performing this operation, please
contact EPA (see page -iv- at the front of this manual).
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4-7
4.7 PROGRAM UPDATE INFORMATION
EPA expects MOBILE4 to undergo future revision to correct
possible errors, improve program performance, and incorporate
changes in the methodology. Users who wish to submit changes or
corrections can mail these to the EPA Motor Vehicle Emission
Laboratory in Ann Arbor, at the address given at the end of this
section.
A list of program errors and User's Guide corrections will be
compiled, if necessary, and distributed to EPA Regional Offices.
EPA does not currently intend to support a user mailing list for
automatic distribution of these corrections. Users should contact
their Regional Offices from time to time. Users who wish to do so
may submit the following Update Request form. In the event a
complete mailing list is assembled, they will be included and sent
any published changes to MOBILE4.
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4-8
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4-9
MOBILE4 UPDATE REQUEST
Mail to: MOBILE4 Emission Factor Project
U. S. EPA Motor Vehicle Emission Laboratory
Emission Control Technology Division
Test and Evaluation Branch
2565 Plymouth Road
Ann Arbor, Michigan 48105
Name and Address of User:
CITY STATE
ZIP
Name(s) and telephone number(s) of individual(s) we may need to
reach to respond to questions:
MOB ILE4-1
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4-11
MOBILE4 UPDATE REQUEST
Mail to: MOBILE4 Emission Factor Project
U. S. EPA Motor Vehicle Emission Laboratory
Emission Control Technology Division
Test and Evaluation Branch
2565 Plymouth Road
Ann Arbor, Michigan 48105
Name and Address of User:
CITY STATE
ZIP
Name(s) and telephone number(s) of individual(s) we may need to
reach to respond to questions:
MOB ILE4-1
-------
Chapter 5
MOBILE4 EXAMPLES
5.0 INTRODUCTI ON
Four examples are provided to illustrate various aspects of
MOBILE4. The user is encouraged to try two or more of these
examples to ensure that the model as compiled is running properly.
5.1 EXAMPLES
The MOBILE4 examples are summarized in Table 5.1-1.
Example
1
la
Ib
Ic
Id
Table 5.1-1
Summary Description of MOBILE4 Examples
Title Content
Basic Run
In-use Fuel
Volatility and
Onboard VRS
Controls
I/M + ATP
Replacement of
MOBILE4 Data
Basic fleet emission rates evaluated
on 1/1/80, 1/1/88, 1/1/90, and 1/1/00.
OUTFMT = 1 (221-column numeric)
OUTFMT = 2 {140-column numeric)
OUTFMT = 3 (112-column descriptive)
OUTFMT = 4 ( 80-column descriptive)
Fleet emission rates, with in-use fuel
volatility control (to 9.0 psi RVP in
ASTM Class C areas) beginning in 1990,
and onboard VRS refueling emission
control beginning in MY 1993;
evaluated on 1/1/80, 1/1/88, 1/1/90,
and 1/1/00.
Fleet emission rates with an I/M
program implemented on 1/1/83 and an
ATP implemented on 1/1/86, evaluated
on 1/1/79, 1/1/80, 1/1/88, 1/1/90,
1/1/00, and 1/1/20.
Fleet emission rates with user-supplied
annual mileage accumulation rates and
vehicle registration distributions by
age, evaluated on 1/1/80, 1/1/88, and
1/1/00.
-------
5-2
5.1.1. Basic Run Example
This example is a basic MOBILE4 run, which reflects
"national average" emission rates without inspection and
maintenance (I/M) or anti-tampering programs (ATP). The user
should note that each scenario output section includes
information on whether I/M or an ATP has been included, and
other information such as temperature and operating mode
percentages.
Note that the input files contain identifying information
to the right of the last columns that will be read by the
program. This is useful in examination of the input files, and
can prove very helpful in the tracking and correction of any
input data errors that may occur.
This example is presented four times, once using each of
the four output formats. This is done only to provide the
reader with illustrations of the possible output formats. Note
that the 221- and 140-column numeric outputs (OUTFMT = 1 or 2)
are "wrapped around" in order to fit it on the page. These
output formats are generally not used when hard copies are
desired. (See section 3.3.1 for discussion of carraige control
characters, which explains why the printed examples la and Ib
are 220 and 139 columns, respectively, rather than 221 and 140.)
-------
1 PROMPT -
MOBILE4 Example la:
TAMFLG -
SPDFLG -
VMFLAG -
MYMRFG -
NEWFLG -
IMFLAG -
ALHFLG -
ATPFLG -
RLFLAG -
LOCFLG -
TEMFLG -
OUTFMT -
4 PRTFLG -
1 IDLFLG -
2 NMHFLG -
2 HCFLAG -
1 80 19.6 75.0 20.6
Ann Arbor MI C
1 90 19.6 75.0 20.6
MI
vertical flag Input, no prompting
OUTFMT = 1 (long (220 column) numeric output format)
default tampering rates
one speed per scenario for all IV
default vmt mlx
default registration and mileage accrual rates
default exhaust emission rates
no I/M program
no additional correction factor Inputs
no ant 1-tampering program
no refueling losses
read In local area parameters as 2nd req sc rec
calculate exhaust temperatures
long 220 column numeric output format
print exhaust MC. CO and NOx emission factor results
do not print Idle emissions results
print NMHC
print HC components
27.3 20.6
Ann Arbor
1 00 19.6 75
Ann Arbor
C
0 20.6
MI C
60. 84. 11
27.3 20.6
5 11.5 20
60.
84. 11.5 11.5 20
27.3 20.6
60. 84. 11.5 11.5 20
1st req sc rec: IREJN,ICY,SPD(1),AMBT,PCCN,PCHC,PCCC
LAP rec: SCNAME,RVPAST.TEMMIN,TEMMAX,RVPBAS,RVPIUS.IUSESY
1st req sc rec: IREJN.ICY.SPD(1).AMBT,PCCN,PCHC,PCCC
LAP rec: SCNAME,RVPAST.TEMMIN,TEMMAX,RVPBAS,RVPIUS,IUSESV
1st req sc rec: IREJN,ICY,SPD(1).AMBT,PCCN,PCHC,PCCC
LAP rec: SCNAME.RVPAST.TEMMIN.TEMMAX.RVPBAS,RVPIUS,IUSESY
Ul
I
LO
-------
MOBILE4 Example la: OUTPUT = 1 (long (220 column) numeric output format)
R
e
g
i
i
i
i
i
i
i
1
i
CY
80 19.6/19.6/19
80 19.6/19.6/19
80 19.6/19.6/19
90 19.6/19.6/19
90 19.6/19.6/19
90 19.6/19.6/19
0 19.6/19.6/19
0 19.6/19.6/19
0 19.6/19.6/19
Vehicle Speeds
.6/19.6/19.6/19
.6/19.6/19.6/19
.6/19.6/19.6/19
.6/19.6/19.6/19
.6/19.6/19.6/19
.6/19.6/19.6/19
.6/19.6/19.6/19
.6/19.6/19.6/19
.6/19.6/19.6/19
.6/19.6/19
.6/19.6/19
.6/19.6/19
.6/19.6/19
.6/19.6/19
.6/19.6/19
.6/19.6/19
.6/19.6/19
.6/19.6/19
Amb
Tmp
.6 78
.6 78
.6 78
.6 78
.6 78
.6 78
.6 78
.6 78
.6 78
P
Alt. 0
Cold/Hot Start 1n Ft. 1
20.6 27.
20.6 27.
20.6 27.
20.6 27.
20.6 27.
20.6 27.
20.6 27.
20.6 27.
20.6 27.
3 20.6
3 20.6
3 20.6
3 20.6
3 20.6
3 20.6
3 20.6
3 20.6
3 20.6
Composite Emission Factors
LDGT HDGV
11.037 20.121
5.648 10.159
2.876 6.779
0.484 0.821
2.029 2.362
67.504 186.457
3.826 6.750
4.855 8.854
2.715 3.478
1.034 2.975
0.349 0.604
0.757 1,797
35.151 69.840
2.020 5.422
3.071 6.300
1.657 2.418
0.561 1.700
0.326 0.539
0.526 1.643
23.258 37.435
1.474 4.301
LDDV LOOT
0.609 0.945
0.609 0.945
1.503 2.119
1.499 1.949
0.600 0.723
0.600 0.723
1.564 1.672
1.447 1.546
0.461 0.633
0.461 0.633
1.392 1.550
1.068 1.205
HDDV
4.916
4.916
MC
8.600
6.566
2.034
15.553 33.627
28.912
2.513
2.513
0.470
4.908
2.331
2.577
12.289 21.953
18.531
2.051
2.051
0.821
4.449
1.859
2.590
10.881 21 .437
8.723
0.830
Al 1 Veh LDGV LDGT1
9.334 0.
4.697
2.409
0.407
1 .821
58.632 0.
4.396 0.
4.430 0.
2.130
0.943
0.284
1 .072
27.650 0.
2.306 0.
2.904 0.
1.208
0.567
0.245
0.884
17.028 0.
1 .418 0.
70S 0. 129
708 0. 129
708 0. 129
710 0.127
710 0. 127
710 0. 127
693 0. 116
693 0.116
693 0.116
500. 1
X
V
R
T
500. 2
500. 3
500. 1
X
V
R
T
500. 2
500. 3
500. 1
X
V
R
T
500. 2
500. 3
LDGV LDGT1
8.967 9.
4.294 4.
2.357 2.
0.410 0.
1.906 1.
56.881 62.
3.052 3.
4.387 4.
1.942 2.
0.917 0.
0.283 0.
1.245 0.
25.952 34.
1.586 1.
2.974 3.
1.059 1.
0.581 0.
0.247 0.
1.087 0.
16.143 22.
1.068 1.
309
782
128
484
914
064
307
644
668
875
350
750
854
974
041
626
568
326
521
849
477
LDGT2
13.664
6.964
4.013
0.482
2.204
75.778
4.614
5. 168
2.785
1 .270
0.348
0.765
35.591
2.089
3.111
1 .699
0.552
0.326
0.534
23.817
1 .469
Vehic le Mix
LDGT2 HDGV LDDV LOOT
0.085 0
0.085 0
0.085 0
0.086 0
0.086 0
0.086 0
0.085 0
0.085 0
0.085 0
.015 0.006 0
.015 0.006 0
.015 0.006 0
.015 0.013 0
.015 0.013 0
.015 0.013 0
.015 0.035 0
.015 0.035 0
.015 0.035 0
.001
.001
.001
.004
.004
.004
.017
.017
.017
HDDV MC
0.045 0.010
0.045 0.010
0.045 0.010
0.034 0.010
0.034 0.010
0.034 0.010
0.029 0.010
0.029 0.010
0.029 0.010
Scenar i o Title
Ann Arbor MI
Ann Arbor MI
Ann Arbor MI
Ann Arbor MI
Ann Arbor MI
Ann Arbor MI
Ann Arbor MI
Ann Arbor MI
Ann Arbor MI
Ln
I
-------
1 PROMPT -
MOBILE4 Example 1t>:
1
1
1
1
1
1
1
1
1
1
1
2
4
1
2
2
1 80 19.6
Ann Arbor
1 90 19.6
Ann Arbor
TAMFLG -
SPDFLG -
VMFLAG -
MYMRFG -
NEWFLG -
IMFLAG -
ALHFLG -
ATPFLG -
RLFLAG -
LOCFLG -
TEMFLG -
OUTFMT -
PRTFLG -
IDLFLG -
NMHFLG -
HCFLAG -
75.0 20.6
MI C
75.0 20.6
MI C
de
on
de
de
de
no
no
no
no
re;
ca
shi
pr
do
pr
pr
27
60
27
60
vertical flag Input, no prompting
OUTFMT = 2 (short (139 column) numeric output format)
default tampering rates
one speed per scenario for all IV
default vmt mlx
default registration and mileage accrual rates
default exhaust emission rates
no I/M program
no additional correction factor Inputs
no ant 1-tampering program
no refueling losses
read 1n local area parameters as 2nd req sc rec
calculate exhaust temperatures
short 139 column numeric output format
print exhaust HC, CO and NOx emission factor results
do not print idle emissions results
print NMHC
1 00 19.6 75.0 20.6
Ann Arbor
MI C
print HC components
3 20.6
84. 11.5 11.5 20
3 20.6
84. 11.5 11.5 20
27.3 20.6
60. 84. 11.5 11.5 20
1st req sc rec: IREJN,ICY,SPD(1),AMBT,PCCN,PCHC,PCCC
LAP rec: SCNAME,RVPAST.TEMMIN,TEMMAX,RVPBAS,RVPIUS,IUSESY
1st req sc rec: IREJN,ICY.SPD(1),AMBT.PCCN,PCHC.PCCC
LAP rec: SCNAME,RVPAST,TEMMIN,TEMMAX,RVPBAS,RVPIUS,IUSESY
1st req sc rec: IREJN.ICY.SPD(1),AMBT,PCCN.PCHC,PCCC
LAP rec: SCNAME,RVPAST,TEMMIN,TEMMAX,RVPBAS.RVPIUS,IUSESY
t_n
I
-------
MOBILE4 Example 1b: OUTFMT = 2 (short (139 column) numeric output format)
R
e Amb.
g CY Tmp
1 80
1 80
1 80
1 90
1 90
1 90
1 0
1 0
1 0
78
78
78
78
78
78
78
78
78
Cold/Hot
20.6
20.6
20.6
20.6
20.6
20.6
20.6
20.6
20.6
27.
27.
27.
27.
27.
27.
27.
27.
27.
Start
3 20.
3 20.
3 20.
3 20.
3 20.
3 20.
3 20.
3 20.
3 20.
Vehicle M1
LDGV
.708
.708
.708
.710
.710
.710
.693
.693
.693
LDGT1LDGT2HDGV
. 129
. 129
. 129
. 127
. 127
. 127
.116
.116
.116
.085
.085
.085
.086
.086
.086
.085
.085
.085
.015
.015
.015
.015
.015
.015
.015
.015
.015
LDDV
.006
.006
.006
.013
.013
.013
.035
.035
.035
P
o
1
6 1
X
V
R
T
6 2
6 3
6 1
X
V
R
T
6 2
6 3
6 1
X
V
R
T
6 2
6 3
X
LDDT
.001
.001
.001
.004
.004
.004
.017
.017
.017
LDGV
8.97
4.29
2.36
0.41
1 .91
56.88
3.05
4.39
1 .94
0.92
0.28
1 .25
25.95
1 .59
2.97
1 .06
0.58
0.25
1 .09
16. 14
1 .07
HDOV
.045 .
.045 .
.045 .
.034 .
.034 .
.034 .
.029 .
.029 .
.029 .
LDGT1
9
4
2
0
1
62
3
4
2
0
0
0
34
1
3
1
0
0
0
22
1
MC
010
010
010
010
010
010
010
010
010
.31
.78
. 13
.48
.91
.06
.31
.64
.67
.87
.35
.75
.85
.97
.04
.63
.57
.33
.52
.85
.48
LDGT2
13.66
6.96
4.01
0.48
2.20
75.78
4.61
5. 17
2.78
1 .27
0.35
0.77
35.59
2.09
3.11
1 .70
0.55
0.33
0.53
23.82
1 .47
Composite Emission Factors
LDGT HDGV LDDV LDDT
1 1 .04
5.65
2.88
0.48
2.03
67.50
3.83
4. 86
2.71
1 .03
0.35
0.76
35. 15
2.02
3.07
1 .66
0.56
0.33
0.53
23.26
1 .47
20
10
6
0
2
186
6
8
3
2
0
1
69
5
6
2
1
0
1
37
4
. 12
. 16
.78
.82
.36
.46
.75
.85
.48
.98
.60
.80
.84
.42
.30
.42
.70
.54
.64
.43
.30
0
0
1
1
0
0
1
1
0
0
1
1
.61
.61
.50
.50
.60
.60
.56
.45
.46
.46
.39
.07
0.95
0.95
2.12
1 .95
0.72
0.72
1 .67
1 .55
0.63
0.63
1 .55
1.21
HDDV
4
4
15
28
2
2
12
18,
2
2
10.
8.
.92
.92
.55
.91
.51
.51
. 29
.53
.05
.05
.88
.72
MC
8.60
6.57
2.03
33.63
0.47
4.91
2.33
2.58
21 .95
0.82
4.45
1 .86
2.59
21 .44
0.83
Al Weh
9.33
4.70
2.41
0.41
1.82
58.63
4.40
4.43
2.13
0.94
0.28
1 .07
27.65
2.31
2.90
1.21
0.57
0.24
0.88
17.03
1 .42
01
I
-------
1 PROMPT -
WOBILE4 Example 1c:
TAMFLG -
SPDFLG -
VMFLAG -
MYMRFG -
NEWFLG -
IMFLAG -
ALHFLG -
ATPFLG -
1
1
1
3
4
1
2
2
1 BO
inn
1 90
4nn
1 00
\rtr\
19.6
Arbor
19.6
Arbor
19.6
Arbor
RLFLAG
LOCFLG
TEMFLG
OUTFMT
PRTFLG
IDLFLG
NMHFLG
HCFLAG
75.0 20.
MI C
75.0 20.
MI C
75.0 20.
MI C
vertical flag Input, no prompting
OUTFMT = 3 (landscape (112 column) descriptive output format)
default tampering rates
one speed per scenario for all IV
def aul t vmt mi x
default registration and mileage accrual rates
default exhaust emission rates
no I/M program
no additional correction factor Inputs
no ant i -tampering program
- no refueling losses
-
-
-
-
-
-
read 1n local area
calculate exhaust
MOBILE4 112 column
print exhaust HC ,
do not print Idle
print NMHC
parameters
temperatures
descMpt 1 ve
as 2nd req sc rec
output format
CO and NOx emission factor results
emissions results
- print HC components
6
6
6
27.3 20.6
60. 84. 11.5 11.5
27.3 20.6
60. 84. 11.5 11.5
27.3 20.6
60. 84. 11.5 11.5
20 LAP
20 LAP
20 LAP
1st req sc rec: IREJN.ICY,
rec: SCNAME.RVPAST.TEMMIN
1st req sc rec: IREJN.ICY,
rec: SCNAME.RVPAST.TEMMIN
1st req sc rec: IREJN.ICY.
rec: SCNAME.RVPAST.TEMMIN
SPD( 1 ) ,
.TEMMAX
SPD( 1 ) .
.TEMMAX
SPD(1).
.TEMMAX
AMBT.PCCN
.RVPBAS
.PCHC.
.RVPIUS,
AMBT.PCCN
.RVPBAS
.PCHC,
.RVPIUS,
AMBT.PCCN
.RVPBAS
.PCHC,
.RVPIUS.
PCCC
IUSESV
PCCC
IUSESY
PCCC
IUSESY
-------
MOBILE4 Example 1C: OUTPUT = 3 (landscape (112 column) descriptive output format
Non-methane HC emission factors Include evaporative HC emission factors.
Cal. Year: 1980 I/M Program: No Ambient Temp:
Antl-tam. Program: No Operating Mode:
Ann Arbor MI ASTM Class: C Minimum Temp:
Base RVP: 11.5 In-use RVP: 11.5 In-use Start Yr:
Veh. Type:
Veh. Speeds:
VMT Mix:
LDGV
19
0
Composite Emission
Non-Meth HC:
Exhaust HC:
Evaporat HC:
Refuel L HC:
Runlng L HC:
Exhaust CO:
Exhaust NOX:
a
4
2
0
1
56
3
.6
.708
Factors
.97
.29
.36
.41
.91
.88
.05
LDGT1
19.6
0. 129
(Gm/M1 le)
9.31
4.78
2. 13
0.48
1 .91
62.06
3.31
LDGT2
19.6
0.085
13.66
6.96
4.01
0.48
2.20
75.78
4.61
LDGT
1 1
5
2
0
2
67
3
.04
.65
.88
.48
.03
.50
.83
78. 1
20.6
60.
2020
HDGV
19
0
20
10
6
0
2
186
6
.6
.015
. 12
. 16
.78
.82
.36
.46
.75
/ 78. 1 / 78. 1 (F) Region
/ 27.3 / 20.6 Altitude
(F) Maximum Temp
LDDV
19.6
0.006
0.61
0.61
1 .50
1.50
LDDT
19
0
0
0
2
1
.6
.001
.95
.95
. 12
.95
: Low
: 500
: 84.
HDDV
19
0
4
4
15
28
.6
.045
.92
.92
.55
.91
. Ft .
(F)
MC
19.6
0.010
a. 60
6.57
2.03
33.63
0.47
Al 1 Veh
9.334
4.697
2.409
0.407
1 .821
58.632
4.396
Cal. Year: 1990
Ann Arbor MI
Base RVP: 11.5
I/M Program: No
Anti-tarn. Program: No
ASTM Class: C
In-use RVP: 11.5
Ambient Temp: 78.1 / 78.1 / 78.1 (F) Region: Low
Operating Mode: 20.6 / 27.3 / 20.6 Altitude: 500. Ft,
Minimum Temp: 60.
In-use Start Yr: 2020
(F)
Maximum Temp: 84. (F)
Cal. Year: 2000
Ann Arbor MI
Base RVP: 11.5
Veh. Type:
Veh. Speeds:
VMT Mix:
I/M Program: No
Antl-tam. Program: No
ASTM Class: C
In-use RVP: 11.5
Ambient Temp: 78.1 / 78.1 / 78.1 (F) Region: Low
Operating Mode: 20.6 / 27.3 / 20.6 Altitude: 500.
Ft.
Minimum Temp: 60. (F)
In-use Start Yr: 2020
Maximum Temp: 84. (F)
I
00
Veh. Type:
Veh. Speeds:
VMT Mix:
LDGV
19.6
0.710
Composite Emission Factors
Non-Meth HC :
Exhaust HC:
Evaporat HC :
Refuel L HC :
Runlng L HC :
Exhaust CO:
Exhaust NOX:
4.39
1.94
0.92
0.28
1 .25
25.95
1.59
LDGT1
19.6
0. 127
(Gm/MI le)
4.64
2.67
0.87
0.35
0.75
34.85
1 .97
LDGT2
19.6
0.086
5. 17
2.78
1 .27
0.35
0.77
35.59
2.09
LDGT
4.86
2.71
1 .03
0.35
0.76
35. 15
2.02
HDGV
19.6
0.015
8.85
3.48
2.98
0.60
1 .80
69.84
5.42
LDDV
19.6
0.013
0.60
0.60
1 .56
1 .45
LDDT
19.6
0.004
0.72
0.72
1 .67
1 .55
HDDV
19
0
2.
2
12,
IB,
.6
.034
.51
.51
.29
.53
MC
19.6
0.010
4.91
2.33
2.58
21 .95
0.82
Al 1
4
2
0
0
1
27
2
Veh
.430
. 130
.943
.284
.072
.650
.306
LDGV
19.6
0.693
LDGT2
19.6
0.085
Composite Emission Factors (Gm/MIle)
Non-Meth HC: 2.97 3.04 3.11
Exhaust HC: 1.06 1.63 1.70
Evaporat HC: 0.58 0.57 0.55
LDGT
3.07
1 .66
0.56
0.015
6.30
2.42
1 .70
0.46
0.46
LDDT
19.6
0.017
0.63
0.63
HDDV
19.6
0.029
2.05
2.05
MC
19.6
0.010
4.45
1 .86
2.59
Al1 Veh
2.904
1 .208
0.567
-------
Refuel L HC: 0.25 0.33 0.33 0.33 0.54 0.245
Runlng L HC: 1.09 0.52 0.53 0.53 1.64 0.884
Exhaust CO: 16.14 22.85 23.82 23.26 37.43 1.39 1.55 10.88 21.44 17.028
Exhaust NOX: 1.07 1.48 1.47 1.47 4.30 1.07 1.21 8.72 0.83 1.418
-------
5-10
-------
1
MOBILE4
4
4
1
2
2
1 80 19
PROMPT -
Example Id:
TAMFLG -
SPDFLG -
VMFLAG -
MYMRFG -
NEWFLG -
IMFLAG -
ALHFLG -
ATPFLG -
6
\nr\ Arbor
1 90 19
6
\nn Arbor
1 00 19
6
\nn Arbor
RLFLAG
LOCFLG
TEMFLG
OUTFMT
PRTFLG
IDLFLG
NMHFLG
HCFLAG
75.0 20.
MI C
75.0 20.
MI C
75.0 20.
MI C
vertical flag Input, no prompting
OUTFMT = 4 (portrait (80 column) descriptive output format)
default tampering rates
one speed per scenario for all IV
def aul t vmt ml x
default registration and mileage accrual rates
default exhaust emission rates
no I/M program
no additional correction factor Inputs
no ant 1-tamper1ng program
- no refueling losses
-
-
-
-
-
-
read In local area
calculate exhaust
portrait 80 column
print exhaust HC ,
do not print idle
print NMHC
parameters
temperatures
descriptive
as 2nd req sc rec
output format
CO and NOx emission factor results
emissions results
- print HC components
6
6
6
27.3 20.6
60. 84. 11.5 11.5
27.3 20.6
60. 84. 11.5 11.5
27.3 20.6
60. 84. 11.5 11.5
20 LAP
20 LAP
20 LAP
1st req sc rec: IREJN.ICY.
rec: SCNAME, RVPAST, TEMMIN
1st req sc rec: IREJN.ICY,
rec: SCNAME, RVPAST. TEMMIN
1st req sc rec: IREJN.ICY,
rec: SCNAME, RVPAST. TEMMIN
SPD( 1 ) ,
.TEMMAX
SPD(l),
.TEMMAX
SPD( 1 ) ,
.TEMMAX
AMBT
.PCCN.PCHC,
.RVPBAS
AMBT
.RVPIUS,
.PCCN.PCHC,
.RVPBAS
AMBT
.RVPIUS,
.PCCN.PCHC,
.RVPBAS
.RVPIUS,
PCCC
IUSESY
PCCC
IUSESY
PCCC
IUSESY
-------
MOBILE4 Example Id: OUTFMT = 4 (portrait (80 column) descriptive output format)
Non-methane HC emission factors Include evaporative HC emission factors.
Cal. Year: I960
Region: Low
I/M Program: No
Ant1-tam. Program: No
Altitude:
Ambient Temp:
Operating Mode:
500. Ft.
78. 1 / 78. 1
20.6 / 27.3
78. 1 F
20.6
Ann Arbor MI ASTM Class: C
Minimum Temp: 60. (F) Maximum Temp: 84. (F)
Base RVP: 11.5 In-use (IU) RVP: 11.5 IU 1st Vr: 2020
Veh. Type: LDGV LDGT1 LDGT2 LDGT
HDGV
LDDV
LDDT
HDDV
MC
AlI Veh
Veh. Spd.
VMT Mix
Campos 1 te
No-Mth HC
Exhst HC
Evap. HC
Refuel HC
Runlng HC
Exhst CO
Exhst NOX
Cal . Year
: 19.6
: 0.708
Emlssl on
: 8.97
: 4.29
: 2.36
: 0.41
: 1 .91
: 56.88
: 3.05
: 1990
Ant
19.6
0. 129
19.6
0.085
Factors (Gm/M1
9.31
4.78
2.13
0.48
1 .91
62.06
3.31
I/M
1-tam.
13.66 1
6.96
4.01
0.48
2.20
le)
1.04
5.65
2.88
0.48
2.03
75.78 67.50
4.61
Region:
Program:
Program:
3.83
Low
No
No
19.6 19.6 19.6
0.015 0.006 0.001
20.12 0.61 0.95
10.16 0.61 0.95
6.78
0.82
2.36
186.46 1 .50 2.12
6.75 1.50 1.95
Altitude:
Ambient Temp:
Operating Mode:
19
0
4
4
15
28
500
78
20
.6
.045
.92
.92
.55
.91
. Ft
. 1 /
.6 /
19
0
8
6
2
33
0
78
27
.6
.010
.60
.57
.03
.63
.47
. 1 /
.3 /
9.
4.
2.
0.
1 .
58.
4.
78.
20.
33
70
41
41
82
63
40
1 F
6
Ann Arbor MI ASTM Class: C
Minimum Temp: 60. (F) Maximum Temp: 84. (F)
Base RVP: 11.5 In-use (IU) RVP: 11.5 IU 1st Yr: 2020
Veh. Type: LDGV LDGT1 LDGT2
LDGT
HDGV
LDDV
LDDT
HDDV MC
Al1 Veh
Veh. Spd.:
VMT Mix:
Compost te
No-Mth HC:
Exhst HC:
Evap. HC:
Refuel HC:
Runlng HC :
Exhst CO:
Exhst NOX:
Cal. Year:
19.6
0.710
Em1 sslon
4.39
1 .94
0.92
0.28
1 .25
25.95
1 .59
2000
Ant
19.6
0. 127
19.6
0.086
Factors (Gm/M1
4.64
2.67
0.87
0.35
0.75
34.85
1 .97
I/M
1-tam.
5. 17
2.78
1 .27
0.35
0.77
le)
4.86
2.71
1 .03
0.35
0.76
35.59 35.15
2.09
Region:
Program:
Program:
2.02
Low
No
No
19.6 19.6 19.6
0.015 0.013 0.004
8.85 0.60 0.72
3.48 0.60 0.72
2.98
0.60
1 .80
69.84 1.56 1.67
5.42 1.45 1.55
Al tltude:
Ambient Temp:
Operating Mode:
19
0
2
2
12
18
500
78
20
.6
.034
.51
.51
.29
.53
. Ft .
. 1 /
.6 /
19
0
4
2
2
21
0
78
27
.6
.010
.91
.33
.58
.95
.82
. 1 /
.3 /
4.
2.
0.
0.
1 .
27.
2.
78.
20.
43
13
94
28
07
65
31
1 F
6
Ann Arbor MI ASTM Class: C
Minimum Temp: 60. (F) Maximum Temp: 84. (F)
Base RVP: 11.5 In-use (IU) RVP: 11.5 IU 1st Yr: 2020
Veh. Type: LDGV LDGT1 LDGT2
LDGT
HDGV
LDDV
LDDT
Veh. Spd.: 19.6 19.6
19.6
HDDV
MC
Al1 Veh
19.6
19.6
19.6 19.6
19.6
-------
VMT Mix: 0.693 0.116 0.065 0.015 0.035 0.017 0.029 0.010
Composite Emission Factors (Gm/M1le)
No-Mth HC:
Exhst HC:
Evap. HCi
Refuel HC:
Runlng HC :
Exhst CO:
Exhst NOX:
2.97
1 .06
0.58
0.25
1.09
16. 14
1 .07
3.04
1.63
0.57
0.33
0.52
22.85
1 .48
3.11
1.70
0.55
0.33
0.53
23.82
1 .47
3.07
1 .66
0.56
0.33
0.53
23.26
1 .47
6.30
2.42
1.70
0.54
1 .64
37.43
4.30
0.46
0.46
1 .39
1.07
0
0
1
1
.63
.63
.55
.21
2.05
2.05
10.88
B.72
4.45
1 .86
2.59
21 .44
0.83
2.90
1.21
0.57
0.24
0.88
17.03
1 .42
I
h-»
u>
-------
5-14
-------
5-15
5.1.2 In-Use Volatility Control and Onboard Refueling
VRS Emission Control Recruirements Example
This example illustrates the use of the options for
modeling an in-use fuel volatility control requirement and an
onboard refueling vapor recovery system (VRS) requirement. The
in-use volatility control requirement information is contained
in the local area parameter record, and reflects a program
limiting in-use volatility to 9.0 psi RVP in ASTM Class C areas
beginning in 1990 (see section 2.2.13). The onboard VRS
descriptive input record is included in the One-time data
section, and reflects a requirement that all gasoline-fueled
vehicles except motorcycles (LDGVs, LDGTls, LDGT2s, and HDGVs)
be equipped with onboard systems beginning in the 1993 model
year (see section 2.2.7).
Note that the parameters of the in-use volatility control
program are reflected in the echoing of the local area
parameter record, with the base RVP applying to all years of
evaluation up to and including 1989, and the in-use
(controlled) RVP applying to 1990 and later evaluation years.
The onboard requirement is not reflected in the "echoed"
portion of the output, but is clearly seen in the much lower
refueling component HC emission factors in the last year of
evaluation.
-------
5-16
-------
1
PROMPT -
MOBILE4 Example 2:
i
3
4
1
2
2
33 2222
1 80 19.6
inn Arbor
1 90 19.6
^nn Arbor
1 00 19.6
Xnn Arbor
TAMFLG -
SPDFLG -
VMFLAG -
MVMRFG -
NEWFLG -
IMFLAG -
ALHFLG -
ATPFLG -
RLFLAG -
LOCFLG -
TEMFLG -
OUTFMT -
PRTFLG -
IDLFLG -
NMHFLG -
HCFLAG -
IOBMV
75.0 20.6
MI C
75.0 20.6
MI C
75.0 20.6
MI C
vertical flag Input, no prompting
RLFLAG = 3 (volatility and onboard control)
default tampering rates
one speed per scenario for all IV
default vmt mix
default registration and mileage accrual rates
default exhaust emission rates
no I/M program
no additional correction factor Inputs
no ant 1 -tampering program
refueling losses
read In local area parameters as 2nd req sc rec
calculate exhaust temperatures
MOBILE4 112 column descriptive output format
print exhaust HC , CO and NOx emission factor results
do not print Idle emissions results
print NMHC
print HC components
, IVOB
27.3 20.6 1st req sc rec: IREJN, ICY, SPD( 1 ) , AMBT , PCCN , PCHC ,
60. 84. 11.5 9.0 90 LAP rec: SCNAME . RVPAST .TEMMIN . TEMMAX . RVPBAS , RVPIUS .
27.3 20.6 1st req sc rec: IREJN , ICY , SPD( 1 ) .AMBT . PCCN , PCHC .
60. 84. 11.5 9.0 90 LAP rec: SCNAME , RVPAST , TEMMIN . TEMMAX , RVPBAS , RVPIUS .
27.3 20.6 1st req sc rec: IREJN , ICY . SPD( 1 ), AMBT , PCCN , PCHC ,
60. 84. 11.5 9.0 90 LAP rec: SCNAME , RVPAST , TEMMIN . TEMMAX , RVPBAS , RVPIUS ,
PCCC
IUSESY
PCCC
IUSESY
PCCC
IUSESY
I
H-«
•^4
-------
MOBILE4 Example 2: RLFLAG = 3 (volatility and onboard control)
Non-methane HC emission factors Include evaporative HC emission factors.
Cal. Year: 1980
Ann Arbor MI
Base RVP: 11.5
I/M Program: No
Anti-tarn. Program: No
ASTM Class: C
In-use RVP: 9.0
Ambient Temp: 78.1 / 78.1 / 78.1 (F) Region: Low
Operating Mode: 20.6 / 27.3 / 20.6 Altitude: 500. Ft
Minimum Temp: 60. (F)
In-use Start Yr: 1990
Maximum Temp: 84. (F)
Veh. Type:
Veh. Speeds:
VMT Mix:
LDGV
19.6
0.708
LDGT1
19
0
.6
. 129
LDGT2
19
0
.6
.085
LDGT
HDGV
19
0
.6
.015
LDDV
19.
0.
6
006
LDDT
19.6
0.001
HDDV
19
0
.6.
.045
MC
19
0
.6
.010
All Veh
Composite Emission Factors (Gm/Mile)
Non-Meth
Exhaust
Evaporat
Refuel L
Runing L
Exhaust
Exhaust
HC:
HC:
HC:
HC:
HC:
CO:
NOX:
8.97
4.29
2.36
0.41
1 .91
56.88
3.05
9
4
2
0
1
62
3
.31
.78
. 13
.48
.91
.06
.31
13
6
4
0
2
75
4
.66
.96
.01
.48
.20
.78
.61
1 1 .04
5.65
2.88
0.48
2.03
67.50
3.83
20
10
6
0
2
186
6
. 12
. 16
.78
.82
.36
.46
.75
0.
0.
1 .
1 .
61
61
50
50
0.95
0.95
2.12
1 .95
4
4
15
28
.92
.92
.55
.91
8
6
2
33
0
.60
.57
.03
.63
.47
9.334
4.697
2.409
0.407
1 .821
58.632
4.396
Cal. Year: 1990
Ann Arbor MI
Base RVP: 11.5
I/M Program: No
Anti-tarn. Program: No
ASTM Class: C
In-use RVP: 9.0
Ambient Temp: 78.1 / 78.1 / 78.1 (F) Region: Low
Operating Mode: 20.6 / 27.3 / 20.6 Altitude: 500. Ft.
Minimum Temp: 60. (F)
In-use Start Yr: 1990
Maximum Temp: 84. (F)
I
I—•
CO
Veh. Type:
Veh. Speeds:
VMT Mix:
LDGV
19.6
0.710
Composite Emission Factors
Non-Meth HC:
Exhaust HC:
Evaporat HC:
Refuel L HC:
Runing L HC:
Exhaust CO:
Exhaust NOX:
2.87
1.76
0.52
0.22
0.36
21 .57
1 .58
LDGT1
19.6
0. 127
(Gm/M1 le)
3.38
2.38
0.49
0.28
0.23
28.29
1 .98
LDGT2
19.6
0.086
3.76
2.52
0.74
0.28
0.22
29.40
2.09
LDGT
3.53
2.44
0.59
0.28
0.22
28.74
2.02
HDGV
19.6
0.015
6. 17
3.36
1.76
0.4B
0.58
63.81
5.74
LDDV
19
0
0
0
1
1
.6
.013
.60
.60
.56
.45
LDDT
19
0
0
0
1
1
.6
.004
.72
.72
.67
.55
HDDV
19
0
2
2
12
18
.6
.034
.51
.51
.29
.53
MC
19.6
0.010
3.92
2.33
1.59
21 .95
0.82
A) 1 Veh
3.023
1 .941
0.540
0.226
0.315
23.082
2.304
Cal. Year: 2000 I/M Program: No
Anti-tarn. Program: No
Ambient Temp: 78.1 / 78.1 / 78.1 (F) Region: Low
Operating Mode: 20.6 / 27.3 / 20.6 Altitude: 500. Ft,
Ann Arbor MI
Base RVP: 11.5
Veh. Type: LDGV
Veh. Speeds: 19.6
VMT Mix: 0.693
ASTM Class: C
In-use RVP: 9.0
LDGT1
19.6
0. 1 16
Minimum Temp: 60.
In-use Start Vr: 1990
LDGT2
19.6
0.085
LDGT
HDGV
19.6
0.015
(F)
LDDV
19.6
0.035
Maximum Temp: 84. (F)
LDDT
19.6
0.017
HDDV
19.6
0.029
MC
19
0
6
010
Al1 Veh
Composite Emission Factors (Gm/M1le)
Non-Meth HC: 1.48 1.78 1.83 1.80 3.77
Exhaust HC: 0.84 1.27 1.32 1.29 2.21
Evaporat HC: 0.26 0.27 0.27 0.27 0.88
0.46
0.46
0.63
0.63
2.05
2.05
3.46
1 .86
1 .60
1 .568
0.981
0.266
-------
Refuel L HC: 0.08 0.10 0.09 0.09 0.13 0.076
Runlng L HC: 0.30 0.15 0.15 0.15 0.55 0.245
Exhaust CO: 10.51 14.64 15.20 14.88 28.83 1.39 1.55 10.88 21.44 11.316
Exhaust NOX: 1.04 1.44 1.43 1.43 4.67 1.07 1.21 8.72 0.83 1.394
-------
5-20
-------
5-21
5.1.3 I/M and ATP Example
This example illustrates the use of a control file which
estimates the impact of an I/M program and an anti-tampering
program (ATP). The I/M and ATP program characteristics are
summarized at the top of the run header. Note that the
scenario output records are now echoing the fact that I/M and
ATP are being accounted for in estimating emission rates. Also
note that no ATP emission credit matrices are required as
program input, since MOBILE4 now calculates the required
matrices internally on the basis of the ATP characteristics
specified by the user on the ATP descriptive input record.
Note that the warning messages M108, M109, and MHO are
printed after the project title. This reflects the
discrepancies in the I/M program and ATP parameters specified
in this example. As noted in section 3.2, I/M programs and
ATPs are generally operated together in any given area, and so
generally would have the same compliance rates, inspection
frequencies, and inspection types.
-------
5-22
-------
1
MOBILE4 E
1
1
1
1
1
2
1
2
1
1
1
3
4
1
2
1
83 30 68
86 75 20
1 79 19.6
Ann Arbor
1 80 19.6
Ann Arbor
1 90 19.6
Ann Arbor
1 00 19.6
Ann Arbor
1 20 19.6
Ann Arbor
PROMPT
xample 3
TAMFLG
SPDFLG
VMFLAG
MVMRFG
NEWFLG
IMFLAG
ALHFLG
ATPFLG
RLFLAG
LOCFLG
TEMFLG
OUTFMT
PRTFLG
IDLFLG
NMHFLG
HCFLAG
- vertical flag Input, no prompting
ATPFLG = 2 ( Ant 1 -tamper 1 ng Program). LAPSV = 1986, ICYIM =
- default tampering rates
- one speed per scenario for al 1 IV
- default vmt mix
- default registration and mileage accrual rates
- default exhaust emission rates
- I/M program
- no additional correction factor Inputs
- ant 1-tamperlng program
- no refueling losses
- read In local area parameters as 2nd req sc rec
- calculate exhaust temperatures
- MOBILE4 112 column descriptive output format
- print exhaust HC , CO and NOx emission factor results
- do not print Idle emissions results
1983
print NMHC
do ont print HC components
20 20 10 070 2 2 2221 2 1 1
2111 11 090. 22211221
75.0 20.6 27.3 20.6
75
75
75
75
0
0
0
0
MI
20
MI
20
MI
20
MI
20
MI
C
C
C
C
C
6
6
6
6
60.
27.
60.
27.
60.
27.
60.
27.
60.
3
3
3
3
84.
20.
84.
20.
84.
20.
84.
20.
84.
1
6
1
6
1
6
1
6
1
1
1
1
1
1
ICVIM,ISTRIN,MODVR1/2,WAIVER(1-2),CRIM.INTYP,IFREQ,ILDT(1-4).I TEST,NUDATA(1-2)
ATP parameters: start, 1st myr, last myr, veh types, Insp pgm type & freq, compliance, disable
1st req sc rec: IREJN,ICY,SPD(1).AMBT,PCCN,PCHC,PCCC
,5 11.5 20 LAP rec: SCNAME.RVPAST.TEMMIN,TEMMAX,RVPBAS.RVPIUS,IUSESY
1st req sc rec: IREJN.ICY.SPD(1).AMBT,PCCN.PCHC.PCCC
,5 11.5 20 LAP rec: SCNAME,RVPAST.TEMMIN,TEMMAX,RVPBAS.RVPIUS.IUSESY
1st req sc rec: IREJN.ICY.SPD(1).AMBT,PCCN.PCHC,PCCC
5 11.5 20 LAP rec: SCNAME,RVPAST.TEMMIN.TEMMAX.RVPBAS,RVPIUS,IUSESY
1st req SC rec: IREJN,ICY,SPD(1),AMBT,PCCN,PCHC,PCCC
5 11.5 20 LAP rec: SCNAME,RVPAST,TEMMIN.TEMMAX,RVPBAS,RVPIUS.IUSESY
1st req sc rec: IREJN,ICY.SPD(1),AMBT,PCCN.PCHC,PCCC
5 11.5 20 LAP rec: SCNAME,RVPAST,TEMMIN.TEMMAX,RVPBAS,RVPIUS.IUSESY
Ui
I
OJ
-------
MOBILE4 Example 3: ATPFLG = 2 (Ant 1-tamper 1 ng Program). LAPSY = 1986, ICYIM = 19
M108 Warning: The ATP compliance rate of 90.0 1s not equal to the I/M compliance rate of 70.0
M109 Warning: The ATP Inspection frequency 1s Annual and the I/M Inspection frequency Is Biennial
M110 Warning: The ATP Inspection type Is Central the I/M inspection type 1s Dec Comp
I/M program selected:
Start year (January 1): 1983
Pre-1981 MVR stringency rate: 30%
First model year covered: 1968
Last model year covered: 2020
Waiver rate (pre-1981): 20.%
Waiver rate (1981 and newer): 10.%
Compliance Rate: 70.%
Inspection type: Computerized decentralized
Inspection frequency Biennial
Vehicle types covered: LDGV - Yes
LDGT1 - Yes
LDGT2 - Yes
HDGV - No
1981 & later MYR test type: 2500 rpm / Idle
Ant 1-tamper!ng program selected:
Start year (January 1): 1986
First model year covered: 1975
Last model year covered: 2020
Vehicle types covered: LDGV
Type: Centralized
Frequency: Annual
Compliance Rate: 90.0%
A1r pump system disablements: Yes
Catalyst removals: Yes
Fuel Inlet restrlctor disablements: Yes
Tailpipe lead deposit test: No
EGR disablement: No
Evaporative system disablements: Yes
PCV system disablements: Yes
Missing gas caps: No
Non-methane HC emission factors Include evaporative HC emission factors.
Cal. Year: 1979 I/M Program: Yes Ambient Temp: 78.1 / 78.1 / 78.1 (F) Region: Low
Anti-tarn. Program: Yes Operating Mode: 20.6 / 27.3 / 20.6 Altitude: 500. Ft.
Ann Arbor MI ASTM Class: C Minimum Temp: 60. (F) Maximum Temp: 84. (F)
Base RVP-. 11.5 In-use RVP: 11.5 In-use Start Yr: 2020
-------
Veh. Type:
Veh. Speeds:
VMT Mix:
LDGV
19.6
0.71 1
LDGT1
19.6
0. 130
LDGT2
19.6
0.085
LDGT
HDGV
19
0
.6
.015
LDDV
19.6
0.003
LDDT
19.6
0.000
HDDV
19.6
0.045
MC
19.6
0.010
Al 1 Veh
Composite Emission Factors (Gm/M11e)
Non-Math HC:
Exhaust CO:
Exhaust NOX:
9.48
59.53
3. 14
9.75
64.85
3.44
14.98
82. 1 1
5.02
1 1 .82
71 .69
4.07
21
208
6
.55
.89
.91
0.76
1 .73
1 .53
0.92
2.08
1 .92
5.07
14.91
29.46
9.55
35.33
0.39
9.942
61 .960
4.546
Cal. Year: 1980
Ann Arbor MI
Base RVP: 11.5
I/M Program: Yes
Anti-tarn. Program: Yes
ASTM Class: C
In-use RVP: 11.5
Ambient Temp: 78.1 / 78.1 / 78.1 (F) Region: Low
Operating Mode: 20.6 / 27.3 / 20.6 Altitude: 500. Ft
Minimum Temp: 60. (F)
In-use Start Yr: 2020
Maximum Temp: 84. (F)
Veh. Type:
Veh. Speeds:
VMT Mix:
LOGV
19.6
0.708
Composite Emission Factors
Non-Meth HC:
Exhaust CO:
Exhaust NOX:
Cal . Year: 1990
Ann Arbor MI
Base RVP: 1 1 .
Veh. Type:
Veh. Speeds:
VMT Mix:
8.97
56.88
3.05
I/M
Ant 1 -tarn.
LDGT1
19.6
0. 129
(Gm/M1 le)
9.31
62.06
3.31
Program:
Program:
ASTM Class:
5 In-use RVP:
LDGV
19.6
0.710
Composite Emission Factors
Non-Meth HC:
Exhaust CO:
Exhaust NOX:
3.88
20.28
1 .54
LDGT1
19.6
0. 127
(Gm/M1 le)
4.25
29.49
1 .84
LDGT2
19.6
0.085
13.66
75.78
4.61
Yes
Yes
C
11.5
LDGT2
19.6
0.086
4.81
29.81
1.96
LDGT
1 1 .04
67.50
3.83
Ambient
Operat 1ng
Minimum
HDGV
19.6
0.015
20. 12
186.46
6.75
Temp: 78. 1
Mode: 20.6
Temp: 60.
LDDV
19.6
0.006
0.61
1.50
1 .50
/ 78. 1 /
/ 27.3 /
(F)
LDDT
19.6
0.001
0.95
2.12
1 .95
78.1 (F)
20.6 Al
HDDV
19
0
4
15
28
Regi on
tltude
Maximum Temp
.6
.045
.92
.55
.91
: Low
: 500.
: 84.
MC
19.6
0.010
8.60
33.63
0.47
. Ft .
(F)
Al 1 Veh
9.334
58.632
4.396
In-use Start Yr: 2020
LDGT
4.48
29.62
1 .89
HDGV
19.6
0.015
8.85
69.84
5.42
LDDV
19.6
0.013
0.60
1.56
1.45
LDDT
19.6
0.004
0.72
1 .67
1.55
HDDV
19
0
2
12
18
.6
.034
.51
.29
.53
MC
19.6
0.010
4.91
21 .95
0.82
Al 1 Veh
3.992
22.445
2.245
Ln
Ui
Cal. Year: 2000
Ann Arbor MI
Base RVP: 11.5
I/M Program: Yes
Anti-tarn. Program: Yes
ASTM Class: C
In-use RVP: 11.5
Ambient Temp: 78.1 / 78.1 / 78.1 (F) Region: Low
Operating Mode: 20.6 / 27.3 / 20.6 Altitude: 500. Ft
Minimum Temp: 60. (F)
In-use Start Yr: 2020
Maximum Temp: 84. (F)
Veh. Type:
Veh. Speeds:
VMT Mix:
LDGV
19.6
0.693
Composite Emission Factors
Non-Meth HC:
Exhaust CO:
Exhaust NOX:
2.55
12.42
0.97
LDGT1
19.6
0. 1 16
(Gm/Mi le)
2.70
19.08
1 .36
LDGT2
19.6
0.085
2.76
19.91
1.35
LDGT
2.
19.
1 .
73
43
36
HDGV
19
0
6
37
4
.6
.015
.30
.43
.30
LDDV
19
0
0
1
1
.6
.035
.46
.39
.07
LDDT
19.
0.
0.
1 .
1 .
6
017
63
55
21
HDDV
19
0
2
10
8
.6
.029
.05
.88
.72
MC
19.6
0.010
4.45
21 .44
0.83
Al 1 Veh
2.544
13.682
1 .327
Cal. Year: 2020
I/M Program: Yes
Anti-tarn. Program: Yes
Ambient Temp: 78.1 / 78.1 / 78.1 (F) Region: Low
Operating Mode: 20.6 / 27.3 / 20.6 Altitude: 500. Ft.
-------
Ann Arbor MI
Base RVP: 11.5
Veh. Type: LDGV
Veh. Speeds: 19.6
VMT Mixi 0.684
ASTM Class: C
In-use RVP: 11.5
Minimum Temp: 60. (F)
In-use Start Yr: 2020
Maximum Temp: 84. (F)
LDGT1
19.6
0.112
LDGT2
19.6
0.086
LDGT
HDGV
19.6
0.015
LDDV
19.6
0.043
LDDT
19.6
0.021
HDDV
19.6
0.029
MC
Al1 Veh
19.6
0.010
Composite Emission Factors (Gm/M11e)
Non-Metn HC: 2.52 2.58 2.65 2.61 6.03 0.50 0.68 2.03 4.45 2.470
Exhaust CO: 12.01 18.05 18.98 18.46 34.03 1.45 1.60 10.78 21.44 13.006
Exhaust NOX: 0.95 1.30 1.30 1.30 4.19 1.10 1.23 8.05 0.83 1.283
Ul
I
NJ
-------
5-27
5.1.4 Replacement of MOBILE4 Data Example
This example illlustrates the use of alternate locality-
specific data for the MOBILE4 annual mileage accumulation rates
and the vehicle registration distributions by age. Note that
the input files containing the annual mileage accumulation
rates and the vehicle registration distributions by age also
include identifying information to the right of the last
columns that will be read by the program. This is advisable
for future reference, and may assist the user in tracking and
correcting of any data input errors. EPA recommends that
similar identfying information be included in the input files
used for SIP-related MOBILE4 runs.
Also note the warning messages that follow the project
title. M 49 is printed six times, once for each vehicle type
for which the input registration distribution by does not sum
to 1.0. In this example, the registration distributions by age
for LDGVs and LDDVs each sum to 0.999 (and are equal by year,
as required); and the registration distributions by age for
LDGTls, LDDTs, and HDDVs each sum to 0.992 (with the
distributions for LDGTls and LDDTs equal by year, as
required). The registration distribution by age summed to
1.001 for motorcycles, resulting in the last printing of M 49.
Values of 1.000 + 0.003 for the sum of user-supplied
registration distributions by age are generally the result of
rounding, and are no cause for concern. Note also that message
M 21 is printed twice, since motorcycles of ages 12 and 13 were
defined to exist in the registration distribution (as 0.5% and
1.3% of the motorcycle fleet, respectively), but had no annual
mileage accumulation rate assigned. See sections 2.2.3 and 3.2.
-------
5-28
-------
1 PROMPT - vertical flag Input, no prompting
MOBILE4 Example 4: MYMRFG = 4 (New mileage accrual rates & registration distributions)
default tampering rates
one speed per scenario for all IV
default vmt mix
new registration and mileage accrual rates
default exhaust emission rates
no I/M program
no additional correction factor inputs
no ant 1-tamper!ng program
no refueling losses
read in local area parameters as 2nd req sc rec
calculate exhaust temperatures
MOBILE4 112 column descriptive output format
print exhaust HC, CO and NOx emission factor results
do not print idle emissions results
. 12800
.07200
.17400
.06200
. 18400
.08300
.19900
.07400
. 12800
.07200
.17500
.08200
.19900
.07400
.04100
.00200
.075 .
TAMFLG
SPDFLG
VMFLAG
MYMRFG
NEWFLG
IMFLAG
ALHFLG
ATPFLG
RLFLAG
LOCFLG
TEMFLG
OUTFMT
PRTFLG
IDLFLG
NMHFLG
HCFLAG
.12100
.06800
.16100
.07600
.16900
.07600
.18100
.06700
.12100
.06800
.16300
.07600
.18100
.06700
.02800
.00000
107 .107
.018
.039 .027
.061 .095 .094 .103
.036 .024 .030 .028
.037 .070 .078
.044 .032 .038
.037 .070 .078
.044 .032 .038
.075 .107 .107
.039 .027 .018
.061 .095 .094
.036 .024 .030
.077 .135 .134
.025 .015 .013
.105 .225 .206
.008 .005 .013
print NMHC
do ont print HC components
11400 .10800 .10200 .09600 .09100
06400 .06100 .05700 .05400 .05100
15000 .13900 .12900 .11900 .11100
07000 .06500 .06100 .05600 .05200
15600 .14400 .13300 .12300 .11400
07100 .06500 .06000 .05600 .05100
16400 .14800 .13400 .12100 .11000
06100 .05500 .05000 .04500 .04100
11400 .10800 .10200 .09600 .09100
06400 .06100 .05700 .05400 .05100
15100 .14000 .12900 .12000 .11100
07000 .06500 .06000 .05600 .05200
16400 .14800 .13400 .12100 .11000
06100 .05500 .05000 .04500 .04100
02100 .01600 .01200 .00800 .00600
00000 .00000 .00000 .00000 .00000
.106 .100 .092 .085 .077 .066 .052
.014 .009 .006 .005 .005 .005 .004
.083 .076 .076 .063 .054 .043
.026 .024 .022 .020 .018 .016
.075 .075 .075 .068 .059 .053
.034 .032 .030 .028 .026 .024
.075 .075 .075 .068 .059 .053
.034 .032 .030 .028 .026 .024
.100 .092 .085 .077 .066 .052
.009 .006 .005 .005 .005 .004
.083 .076 .076 .063 .054 .043
022 .020 .018 .016
082 .062 .045 .033
007 .006 .005 .004
046 .033 .029 .023
000 .000 .000 .000
.086
.036
.086
.036
. 106
.014
. 103
.028
. 131
.01 1
. 149
.000
1 80 19.6 75.0 20.6 27
Ann Arbor
1 90 19.6 75.
Ann Arbor
026 .024
099 .090
010 .008
097 .062
000 .000
3 20.6
84. 11
.08600 .08100 .076
.04800 .04600 .043
.10300 .09500 .088
.04800 .04500 .042
.10500 .09700 .090
.04700 .04400 .040
.10000 .09000 .082
.03700 .03300 .030
.08600 .08100 .076
.04800 .04600 .043
.10300 .09500 .088
.04800 .04400 .041
.10000 .09000 .082
.03700 .03300 .030
.00400 .00200 .002
.00000 .00000 .000
JULMVR.LDGV..my ages
.LDGV..my ages
.LDGT1.my ages
.LDGT1.my ages
.LDGT2.my ages
.LDGT2.my ages
.HDGV..my ages
.HDGV..my ages
.LDDV..my ages
.LDDV..my ages
.LDDT..my ages
.LDDT..my ages
.HDDV..my ages
.HDDV..my ages
.MC....my ages
.MC....my ages
AMAR.LDGV..my ages 1-
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
1-10
1 1-20
1-10
1 1-20
1-10
1 1-20
1-10
1 1-20
1-10
1 1-20
1-10
1 1-20
1-10
11-20
1-10
1 1-20
10
.LDGV..my ages 11-20
.LDGTI.my ages 1-10
.LDGTI.my ages 11-20
.LDGT2.my ages 1-10
.LDGT2.my ages 11-20
.HDGV..my ages 1-10
.HDGV..my ages 11-20
.LDDV..my ages 1-10
.LDDV..my ages 11-20
.LDDT..my ages 1-10
.LDDT..my ages 11-20
.HDDV..my ages 1-10
.HDDV..my ages 11-20
.MC....my ages 1-10
.MC....my ages 11-20
I
NJ
Ml C 60
0 20.6 27.3 20.6
.5 11.5 20
MI C 60.
84. 11.5 11.5 20
1 00 19.6 75.0 20.6 27.3 20.6
Ann Arbor
MI C 60. 84. 11.5 11.5 20
1st req sc rec: IREJN,ICY.SPD(1),AMBT,PCCN.PCHC,PCCC
LAP rec: SCNAME,RVPAST,TEMMIN.TEMMAX,RVPBAS,RVPIUS.IUSESY
1st req sc rec: IREJN,ICY.SPD(1),AMBT,PCCN,PCHC.PCCC
LAP rec: SCNAME.RVPAST.TEMMIN.TEMMAX.RVPBAS.RVPIUS,IUSESY
1st req sc rec: IREJN.ICY.SPD(1).AMBT.PCCN.PCHC,PCCC
LAP rec: SCNAME.RVPAST.TEMMIN,TEMMAX.RVPBAS,RVPIUS,IUSESY
-------
MOBILE4 Example 4: MYMRFG = 4 (New mileage accrual rates & registration distributions)
M 49 Warning: 0.999 MYR sum not = 1. (will normalize)
M 49 Warning: 0.992 MYR sum not = 1. (will normalize)
M 49 Warning: 0.999 MYR sum not = 1. (will normalize)
M 49 Warning: 0.992 MYR sum not = 1. (will normalize)
M 49 Warning: 0.992
MYR sum not = 1. (will normalize)
M 49 Warning: 1.00 MYR sum not = 1. (will normalize)
M 21 Warning: 0.500E-02 registration with zero mileage
M 21 Warning: 0.130E-01 registration with zero mileage
Non-methane HC emission factors Include evaporative HC emission factors.
User supplied mileage accrual distributions, veh registration distributions.
Cal. Year: 1980 I/M Program: No Ambient Temp: 78.1 / 78.1 / 78.1 (F) Region: Low
Anti-tarn. Program: No Operating Mode: 20.6 / 27.3 / 20.6 Altitude: 500. Ft.
U)
o
Ann Arbor MI
Base RVP: 11.5
ASTM Class: C
In-use RVP: 11.5
Minimum Temp: 60. (F)
In-use Start Yr: 2020
Maximum Temp: 84. (F)
Veh. Type:
Veh. Speeds:
VMT Mix :
LDGV
19.6
0.740
Composite Emission Factors
Non-Meth HC:
Exhaust CO:
Exhaust NOX:
7.30
47.07
2.89
LDGT1
19.6
0. 139
(Gm/M1 le)
9.06
62.37
3.29
LDGT2
19.6
0.083
14.50
81.10
4.80
LDGT
1 1 .09
69.36
3.86
HDGV
19.
0.
22.
209.
7.
6
013
31
39
12
LDDV
19
0
0
1
1
.6
.006
.58
.46
.48
LDDT
19
0
0
2
1
.6
.001
.94
. 1 1
.94
HDDV
19
0
4
13
26
.6
.012
.06
. 10
.33
MC
19
0.
7,
28,
0.
.6
.006
.81
.79
.55
Al 1 Veh
8. 262
53.367
3.410
User supplied mileage accrual distributions, veh regis|ration distributions.
Cal. Year: 1990 I/M Program: No
Anti-tarn. Program: No
Ambient Temp: 78.1 / 78.1 / 78.1 (F) Region: Low
Operating Mode: 20.6 / 27.3 / 20.6 Altitude: 500. Ft.
Ann Arbor MI
Base RVP: 11.5
Veh. Type: LDGV
Veh. Speeds: 19.6
ASTM Class: C
In-use RVP: 11.5
Minimum Temp: 60. (F)
In-use Start Yr: 2020
LDGT1
19.6
LDGT2
19.6
LDGT
HDGV
19.6
LDDV
19.6
Maximum Temp: 84. (F)
LDDT HDDV MC
A I I Veh
19.6
19.6
19.6
-------
VMT Mix:
0.735
0. 136
0.083
0.013
0.01 1
0.004
0.012
0.006
Composite Emission Factors (Gm/M1le)
Non-Meth HC:
Exhaust CO:
Exhaust NOX:
3. 1 1
15.94
1 . 15
4.40
33.88
1 .94
5.85
40.37
2.30
4.95
36.34
2.08
10.50
84.23
5.54
0.49
1 .42
1 .34
0
1
1
.72
.67
.56
2.37
11.17
18.00
5.39
19.45
O.B3
3.578
21 .052
1 .614
User supplied mileage accrual distributions, veh registration distributions.
Cal. Year: 2000 I/M Program: No Ambient Temp: 78.1 / 78.1 / 78.1 (F) Region: Low
Anti-tarn. Program: No Operating Mode: 20.6 / 27.3 / 20.6 Altitude: 500. Ft.
Ann Arbor MI
Base RVP: 11.5
ASTM Class: C
In-use RVP: 1 1 .5
Minimum Temp: 60. (F)
In-use Start Vr: 2020
Maximum Temp: 84. (F)
Veh. Type:
Veh. Speeds:
VMT Mix:
LOGV
19.6
0.714
Composite Emission Factors
Non-Meth HC :
Exhaust CO:
Exhaust NOX:
2.64
12.61
0.95
LDGT1
19.6
0. 122
(Gm/Mi le)
3. OB
23.50
1 .51
LDGT2
19.6
0.082
3.44
26.82
1 .60
LDGT
3
24
1
.22
.83
.55
HDGV
19.6
0.013
6.92
40.71
4.47
LDDV
19.
0.
0.
1 .
1 .
6
033
41
32
00
LDDT
19.
0.
0.
1 .
1 .
6
018
63
55
20
HDDV
19
0
2
10
8
.6
.012
.04
.21
.43
MC
19
0
5
19
0
.6
.006
.32
.45
.83
All Veh
2.716
14.931
1.213
I
U)
------- |