SHORT EMISSION TESTS AND STANDARDS
(see also Instrument Specifications)

Alternative I/M Short Test Procedures, E. Herzog, L. Snapp,
E. Tierney, EPA-AA-TSS-I/M-90-3, January 1991.

This report describes in detail new test procedures designed
to minimize test variability, and the resulting false
failures of new technology vehicles. There are currently six
promulgated test procedures. The new procedures differ from
the current ones in that they include controlled
pre-conditioning, second chance testing, and sampling and
score selecting algorithms. These are intended to minimize
the variability in testing conditions and thereby reduce
false failures of clean vehicles. High emitting vehicles
which have been escaping detection with the current test
procedures will continue to do so under the new ones. It is
EPA's hope that these new procedures will improve the
possibility of using more stringent cutpoints and non-idle
test modes in the future to detect these high emitters by
eliminating the additional false failures that would
otherwise occur by instituting such measures under current
procedures.

Technical Appendix to Federal Register Notice of Proposed

Rulemaking: Alternative Emissions Performance Warranty Short
Test for Ford Vehicles; 2500 RPM/Idle Test, September 1982.

This appendix provides technical background information on
the proposed Engine Restart Idle Test and the Engine Restart
2500/Idle Test. It includes an in-depth discussion of the
1980 and 1981 Ford technologies of concern. It discusses the
possible failures of these vehicles as a result of excessive
idling. It provides the rationale for the proposed tests.

Recommendation Regarding the Selection of Idle Emission

Inspection Cutpoints for Inspection and Maintenance Programs

Requiring Only Carbon _ Monoxide Emission Reductions,
S. Vintilla, EPA-AA-IMS-81-13, PB 81 215 444, May 1981.

This report is a supplement to EPA-AA-IMS-81-1, "Recommen-
dations Regarding the Selection of Idle Emission Inspection
Cutpoints for Inspection and Maintenance Programs". The
original report described methods for selecting HC and CO
cutpoints given an idle emission data base and recommended
specific HC and CO cutpoints by model year groupings for
desired program failure rates. The recommended cutpoints in
the original report were intended for use in I/M programs in
areas which require only HC, or both HC and CO, emission

-17-


OTHER FUELS

Derivation of Technology Specific Effects of the Use of

QOxygenated Fuel Blends on Motor Vehicle Exhaust Emissions,
EPA-AA-TSS-PA-88-1, October 1988.

The report is a supporting document to the report, ‘Guidance
on estimating motor vehicle emission reductions from the use
of alternative fuels and fuel blends.’ It presents the data
and calculations which were used to estimate the effects of
gasoline/oxygenate fuel blends on vehicle exhaust emissions.
Data were gathered from several studies of fuel blends., and
include tests of blends with methanol, ethanol, tert-butyl
alcohol, and MTIBE. Effects are calculated separately for
vehicles with different emission control technology. The
report discusses exhaust emissions of hydrocarbons, carbon
monoxide, and oxides of nitrogen.

Evaporative Emissions from the Fourteen Car DOE (Department

ge qnergy) Gasoline/Methanol Blend Fleet, H.E. Dietzmann and
Harvey, EPA-AA-TSS-PA-85-3, Contract EPA-68-003-. 73192,

Saly 1985.

The purpose of the report was to investigate the effect on
evaporative emissions of mileage accumulation with a
gasoline/methanol/cosolvent splash blend versus mileage
accumulation with the base gasoline. The test program was
carried out under EPA contract 68-03-3192 with Southwest
Research Institute. Evaporative emission tests were
conducted on a 14-vehicle fleet undergoing driveability
testing for the Department of Energy at Southwest Research
Institute. Seven vehicles accumulated mileage on a
gasoline-alcohol blend containing four percent methanol, two
percent ethanol and two percent t-butyl alcohol (TBA). The
results of the tests are summarized within the report. Also
included are recommendations for additional research.

The Effect of Gasohol on I/M Programs, R. Michael, EPA-AA-
IMS-81-22, PB 83 138 073, November 1981.

A test program of about 200 1976 and 1978 Portland vehicles
was designed to determine the effects of the use of gasohol
(10% ethanol, 90% gasoline by volume) on ability to pass an
I/M test. Gasohol generally caused a change in the failure
rate, depending on the idle test used. The failure rate
using the first idle portion of the Two-Speed Idle Test
increased with gasohol from 39% to 46%. The failure rate
using the second idle portion decreased with gasohol from 27%

-38-


I/M CALIBRATION GASES

. EPA_Recommended Practice for Naming I/M Calibration Gas: A

Discussion for I/M Programs, EPA-AA-TSS-83-8-A, PB 84 185
222, Sept 1983.

‘This report discusses the use of calibration gases in I/M
programs and introduces a Recommended Practice for gas
manufacturers to use in naming I/M calibration gas cylinders.
Details of the Recommended Practice are presented in a
parallel report entitled "EPA Recommended Practice for Naming
I/M Calibration Gases" (EPA-AA-TSS-83-8-B). EPA recommends
that calibration gases contain HC and CO with nitrogen as the
diluent. C02, where needed, should be purchased in separate
cylinders. Propane should be used as the HC component in
order to avoid traceability and condensation problems
associated with hexane. Gas concentrations should fall
between 1-2% CO, 200-800 ppm propane and 4-6% C02. For gas
concentrations greater than 500 ppm propane and 4% CO, the
sample should be analyzed using gas chromatography to avoid
CO/propane interference problems.

EPA Recommended Practice for Naming I/M Calibration Gas,
EPA-AA-TSS-83-8-B, PB 84 165 042, Sept 1983.

This report establishes a set of procedures for blending,
analyzing and labeling I/M calibration gases. These
procedures are intended to be used by manufacturers who wish
to label calibration gases with the statement: "made in
accordance with the EPA Recommended Practice for naming I/M
calibration gas". An explanation of how calibration gases
are used in I/M programs is provided in a parallel report
entitled "EPA Recommended Practice for Naming I/M Calibration
Gas: A Discussion for I/M Programs" (EPA-AA-TSS-83-8-A). The
procedure begins with analyses of individual component gases
for impurities and determination of analyzer response (linear
. o£ non-linear). Calibration curves and equations describing
instrument response must be generated monthly for use with
NBS or other’ standards. Quality control . measures are
specified for gas blending and cylinder charging, including
checks for ‘concentration, homogeneity and process accuracy.
Also included are guidelines for cylinder labeling and
documentation.

-34-


Low Cost Approaches to Vehicle Emissions Inspection and
Maintenance, EPA-AA-IMS-81-7, PB 82 214 982, August 1981.

This report addresses an I/M program in which only idle co
emissions are measured. In comparison with most common I/M
programs, which also test idle hydrocarbon emissions, this
approach will achieve the same amount of CO emission
reduction and is only moderately less effective in reducing
HC emissions. Repairs will be much simpler and cost much
less in a "CO anly" program since carburetor adjustments will
usually be the only necessary repair for pre-1981 vehicles.
This type of repair will cost between $6 and $10, compared to
average repair costs of $18 to $30 in a conventional
program. The “CO only" program will also improve fuel
economy of repaired vehicles by 4%. The report concludes
that a "CO only" I/M program offers significant reductions in
total HC and CO emissions from automobiles at a lower cost
than most conventional I/M programs.

Discussion of the Selection of Coverage and Frequency

Alternatives in Inspection and Maintenance Programs,
J. Armstrong, EPA-AA-IMS-81-17, PB 82 112 434, August 1981.

Automobile Inspection/Maintenance (I/M) program managers are
faced with many decisions when designing and implementing an
emissions inspection program on how to best serve the needs

of their local area. All of these decisions are impacted by
both technical and socio-economic considerations. This
report will examine those decisions which concern the
coverage of the program and the frequency of inspection.

Specifically, this report addresses the concerns surrounding
the selection of the geographic area, vehicles classes, and
model years included in the program. Additionally, this
report discusses the impact of including change-of-ownership
inspection and/or random roadside checks along with the
annual cycle.

EPA _I/M Model Program Guidelines, Request for Proposal (RFP),
EPA-AA-IMS-80-7, PB 81 203 580, November 1980.

The model RFP is a guide for state and local agencies to
follow in developing a contract with the organization that
will administer and operate their I/M program. It contains
sections on program information, contract and operating
requirements, equipment specifications, administrative
conditions, bidder qualifications and a cost proposal.

Decentralized Private Garage I/M Program Cost Calculation

Worksheet, IMS-006-CW-2, I/M Staff, August 1979.

-43-


After suitable baselines were established, various components
were made inoperative in the emission control system.
Complete FIP, HFET, and I/M tests were run for each vehicle
condition. This report presents the measured data taken
during the tests.

Derivation of 1981 and Later Light Duty Vehicles Emission

Factors for Low Altitude, Non-California Areas, D. Hughes,
EPA-AA-IMS-80-8, PB 81 177 966, November 1980.

This report describes the methodology used in revising the
emission factor equations for the post-1980 light duty
vehicle fleet. It presents and discusses data on which the
revisions are based, and outlines the pertinent assumptions
used to make calculations. The report is only concerned with
the non-I/M case for low altitude, non-California, gasoline-
fueled, post-1980 model year light duty vehicles.

Exhaust Emission from In-Use Passenger Cars Equipped with
Three Way Catalysts, J. White III, G. Jones, and D. Niemczak,

SAE 800823, June 1980.

This paper presents the results of an exhaust emission
testing program conducted by EPA in which 686 1978-1979
passenger cars of various makes and models were tested. Each
vehicle tested was equipped with a three-way catalyst system
and was certified to California standards. The purpose of
the program was to gather information on the ability of the
three-way system to meet emission standards in the future.
The results indicate the these systems are capable of
achieving low emission levels, although high levels are
possible due to defects, deterioration, or tampering.

The Need for I/M for Current and Future Motor Vehicles,
T. Cackette, P. Lorang, D. Hughes, SAE 790782, August 1979.

The majority of vehicles on the road today exceed their
design emission standards. This failure to achieve design
emission levels is primarily attributed to improper
maintenance, tampering with emission controls, and misfueling
catalyst cars with leaded gasoline. A method of reducing
improper maintenance, tampering, and misfueling is periodic
emission inspection and maintenance (I/M) programs.

This report discusses I/M's ability to deal with in-use
emission problems and contrasts I/M to other mobile source
emission control strategies. The results of EPA's Portland,
Oregon, I/M program are presented. This study shows I/M to
be effective in reducing emission levels.

-ll-


I/M TEST VARIABILITY

I/M Test Variability Observed in the Louisville I/M Program,

Landman, EPA-AA-TSS-I/M-90-7, August 1990.

=PA conducted this test program on 271 1981-1988 model year
vehicles, that had failed the Louisville, Kentucky I/M
program, to determine the effect of an immediate second
chance test. The second chance tests were of two types; an
immediate retest and a similar test with a three minute 2500
rpm, no load pre-conditioning cycle. The results showed that
the pre-conditioning cycle did very little to change the
pass/fail rate compared to an immediate retest. However, the
pre-conditioning cycle did have a significant effect on
reducing the failure rate of vehicles that exceeded only the
hydrocarbon standard.

Variability of I/M Test Scores Over Time, Southwest Research
Institute, EPA-460-3-88-008, September 1988.

This report provides a description and the results of a test
program conducted on 25 1981 and older model year vehicles to
determine the variability in I/M short test emission results,
the impact of no-load pre-conditioning on I/M emission
results, and the emission differences between a fully warmed
vehicle and a soaked vehicle having undergone minimum
operation. Test results showed a reduction in hydrocarbon
emissions following pre-conditioning and higher emissions
following a three hour soak. Carbon monoxide emissions were
low both before and after pre-conditioning but were
noticeably higher after the three hour soak.
Pre-conditioning following the three hour soak return the
carbon monoxide emissions to previous levels.

I/M Test Variability, Landman, EPA-AA-TSS-I/M-87-2, April 1987.

This report summarizes the results of an EPA test program to
determine the effects of various pre-conditioning cycles on
vehicles that exhibit variable I/M emission results. A
secondary objective was to characterize the FTP emissions of
the I/M variable vehicles. In 1985, EPA tested approximately
100 1983-1985 model year vehicles, that had failed the
Maryland I/M test program, at the EG&G Virginia Test
Laboratory. The data suggest that I/M emissions from
closed-loop fuel injected cars equipped with air injection
are less affected by various pre-conditioning cycles than are
closed-loop carbureted cars equipped with air injection.
Forty-eight vehicles were FTP tested and the results were
used to determine the percentage of excess hydrocarbon and
carbon monoxide emissions that I/M tests identify.

-21-


to 23%. The failure rate using the full Two-Speed Idle Test
(testing at both idle and 2500 rpm) remained essentially
unchanged at 35%. The change in failure rate was almost
entirely due to CO emission changes, not HC.

Effects of Gasohol on Idle HC_and CO Emissions, T. Darlington
and R. Lawrence, EPA-AA-IMS-80-4, PB 80 190 655, March 1980.

This report discusses the results of a study to investigate
the effects of gasohol on CO and HC emissions as detected by
the idle test. Three vehicles were set up to operate on
either gasoline or gasohol. CO emissions were varied on each
of the three cars by adjusting the idle. mixture screws, and
HC emissions were varied by inducing a misfire with a misfire
generator. At each CO and HC value, the fuel was switched
from gasoline to gasohol to determine the effect on tailpipe
emissions. As cars were maladjusted, gasohol was found to
reduce idle CO about 1.1%. The reduction was relatively
constant for all three cars between idle mixture settings of
1.5% and 6.0% CO, and the catalyst cars experienced a greater
average reduction. [Idle HC exhaust reductions attributable
to gasohol were vehicle dependent. The non-catalyst car
experienced almost no reduction, while catalyst vehicles had
substantial reductions with gasohol.

-39-


without maladjusted idle mixture. I/M would therefore be
capable of producing some CO reductions from vehicles
operated in cold temperatures. The results and conclusions
in this report should be viewed as preliminary until the
State of Alaska presents data on in-use vehicle testing.

Four vehicles were deliberately maladjusted and tuned up to
simulate the effects of an I/M program on vehicles needing
emission-related repairs. The results indicated that I/M has
the potential for reducing CO emission from in-use vehicles
operated at temperatures below 75°F. Specifically, for all
test cycles used, reductions in CO emissions occurred when
vehicles with maladjusted idle mixture and disconnected choke
assists were tuned-up. This relationship did not necessarily
occur with the repair of the disconnected heated air intake
system, possibly because colder, denser air passes through
the carburetor in this case, resulting in a leaner air fuel
mixture and lower CO emissions.

The Portland Study, H.Ashby, EPA-AA-TEB-82-7, June 1982.

This report describes the two phases of the Portland Study, a
contractor-operated vehicle emission test program that was
conducted in Portland, Oregon, over a five-year period
beginning in 1977. The report includes information on the
history of the program, the objectives of the various tasks
that were completed, program design, and some of the problems
encountered. It does not include any test results, which are
abstracted elsewhere in this document.

Evaluation of I/M Effectiveness Using Emission Factors Data:
Phoenix vs. Other  Low-Altitude, Non-California Sites,

J. Rutherford, EPA-AA-IMS-81-23, PB 83 150 417, October 1981.

This report. presents an analysis of emission factor (EF) data
‘directed towards the effects of the Phoenix, Arizona I/M
program. Phoenix has been a site for EF testing for several
years, both before and after the advent of its I/M program.
Federal Test Procedure (FTP) data recorded from EF testing in
Phoenix and several non-I/M cities provide an opportunity to
evaluate the effectiveness of the I/M program in reducing
emission from in-use light duty vehicles. Statistical
evaluation of the data indicates a significant reduction in
both HC and CO emissions due to I/M in Phoenix as compared
with non-I/M cities.

Effect of Low Cost Repairs on I/M Failed Vehicles,
R. Michael, EPA-AA-IMS-81-19, PB 83 140 111, September 1981.

This study was designed to determine whether simple


INSTRUMENT SPECIFICATIONS

Review of the Massachusetts Vehicle Emissions Test Equipment
Specification, Booz, Allen & Hamilton, EPA-460/3-82-001,

PB-82 252 966, January 1982.

This report is the result of a contract to review the draft
analyzer specification and develop a final specification for
the Massachusetts I/M program based on a detailed review of
existing analyzer specifications and input from knowledgeable
industry and government sources. Manufacturers comments and
EPA's recommended procedures were also used to develop
specifications for a quality assurance program. The report
provides the technical and performance specifications that
were finally developed. It also provides proposal evaluation
methodology and criteria. .

Draft EPA Recommended Practice for Naming I/M Calibration Gas,
T.Darlington, EPA-AA-IMS-81-16, PB 83 139 766, September 1981.

This report explains how calibration gases will be used in
I/M programs, and identifies the problems states may have in
obtaining accurate gases. A Recommended Analysis Practice
for gas manufacturers to use when naming I/M calibration
gases is presented. States are encouraged to procure gases
named according to this Recommended Practice for their own
use, and to require licensed inspection stations to procure
them to ensure that they are obtaining accurate calibration
gases which meet the terms of the Emission Performance
Warranty [207(b)], and to improve the general quality of
their I/M programs.

Recommended Specifications for Emission Inspection Analyzers:
Change Notice Number One, W. Clemmens, EPA-AA-IMS-80-5-C,

PB 81 195 760, April 1981.

This report changes EPA's recommended specifications for
emission inspection analyzers based on recent results of
several engineering design studies by equipment manufactur-
ers. The report gives section by section changes in concepts
or specific wording and reasons for the changes. Most
changes have been made to allow manufacturers more
flexibility in analyzer design, to reduce design and
production costs, and to clarify the intent of certain
specifications.

-32-


reductions in order to attain the National Ambient Air
Quality Standards. This report is intended to aid I/M
programs, which require only CO emission reduction, in the
selection of cutpoints, prediction of failure rates, and
estimation of I/M emission benefits.

Recommendation Regarding the Selection of Idle Emission

Inspection Cutpoints for Inspection and Maintenance Programs,
D. Noddings, EPA-AA-IMS-81-1, PB 81 188 922, January 1981.

This report addresses idle hydrocarbon (HC) and carbon
monoxide (CO) cutpoints and expected resulting failure rates
in an I/M program. - Recommended cutpoints are included for
various failure rates both in the first year of an I/M
program and in its second year. The analysis applies to both
centralized and decentralized programs.

Evaluation of Applicability of the INCOLL Procedure as an I/M
Strategy, B. Smuda,— EPA-AA-IMS-81-5, PB 81 202 715,

November 1980.

This report presents testing results which were gathered to
investigate the suitability of using the INCOLL procedure as
an emissions inspection and maintenance (I/M) testing
procedure compared to existing I/M testing procedures. The
INCOLL procedure utilizes engine and transmission inertial
forces to produce pressures and temperatures in the engine
that will generate significant quantities of exhaust
emissions. The existing I/M test procedures utilize steady
state engine operating modes to produce’ significant
quantities of exhaust emissions. The test sequence consisted
of FTP, INCOLL, LA-4 and I/M cycles. The test sequence was
applied to six vehicles in various states of tune.

Emission Control System Performance Warranty Short Tests and

Warranty Regulations; Final Rules, 45 Federal Register 34802,
May 22, 1980.

This action establishes emission performance warranty "short
tests" as provided in Section 207(b) of the Clean Air Act, 42
U.S.C. 7541(b). These short tests and corresponding warranty
regulations [proposed April 20, 1979; 44 FR 23784] will be
used in conjunction with I/M programs. Under certain
circumstances, a vehicle owner will be entitled to repairs at
the manufacturer's expense if the vehicle exceeds short test
standards. This action promulgates three test procedures: an
idle test, a two speed idle test and a two-mode loaded test
for 1981 and later model year light duty vehicles and light
duty trucks and 1982 and later model year vehicles at high
altitudes. For each test, uniform standards apply to all

-18-


are examined: (1) whether the lead content in the fuel tank
is over the legal limit of 0.05 g/gal.; (2) whether the fuel
inlet restrictor was enlarged or removed to accommodate a
leaded fuel nozzle and (3) whether lead deposits are detected
in the tailpipe using Plumbtesmo test paper. Several
approaches to anti-tampering programs are covered, including
periodic inspection, change-of-ownership inspections and
random audits. Methods for calculating program benefits are
detailed, along with tabulations of specific emission
reductions and sample calculations.

The excess emissions due to tampering and the emission
reduction benefits developed in this report are incorporated
in EPA's MOBILE3 emission factor model. MOBILE3 output which
reflects benefits from an  anti-tampering/anti-misfueling
program can be used in SIP inventory calculations in the same
manner as normal MOBILE3 output.

The Emission Effects of Misfueling Five 1981-82 Model Year
Automobiles With 10 Continuous Tankfuls of Leaded Gasoline,

R.Michael, EPA-AA-TSS-83-2, July 1983.

A test program was initiated to study the effects of
misfueling on late model vehicles in order to help predict
the effect of misfueling on fleetwide emissions in the
1980's. Five 1981 and 1982 model year vehicles with around
25,000 and 15,000 miles accumulated, respectively, were
obtained and tested in as received condition for emission
levels. In all, ten tankfuls of leaded fuel were put into
each vehicle and mileage was accumulated on a test track.
Emission levels and fuel economy were periodically
evaluated. All vehicles experienced steadily increasing
emission levels of both CO and HC with more and more
misfueling. Three-way catalyst vehicles also experienced
increasing NOx emissions, as well. In general, HC emissions
were four times base levels and CO emissions were three times
base levels after ten tankfuls of leaded gas. NOx emissions
in the three way catalyst vehicles were double the baseline
levels. Most of the catalyst deactivation occurs within four
tankfuls of leaded gasoline, although emission levels
continue to increase with further misfueling.

-24-


Light Duty Vehicle and Light Duty Truck Emission Performance
Warranty; Short Tests and Standards, IMS-009-ST-1, PB 80

125 602, December 1979.

This report addresses the relationship between short test
emission results and emissions measured by the Federal Test
Procedure (FTP) for 1981 and later model year light duty
vehicles and light duty trucks. As provided in section
207(b) of the Clean Air Act, EPA must establish an Emission
Performance Warranty if a short test can be developed which
is: 1) available, 2) in accordance with good engineering
practice, and 3) reasonably capable of being correlated with
the Federal certification test, FTP. This report recommends
three short tests that meet the above criteria: idle, two
speed idle and two mode loaded. The test procedures,
necessary equipment and short test standards are all
described in this report.

-20-


Recommended Specifications for Emission Inspection Analyzers,
W. Clemmens, EPA-AA-IMS-80-5-B, PB 81 153 504, September 1980.

This report includes EPA's recommended specifications for
inspection analyzers in I/M programs. EPA recommends

manually operated emissions analyzers for centralized I/M
programs and computerized emissions analyzers for decentral-
ized ones (for maximum quality assurance and consumer
confidence). The report also discusses optional features for
the inspection analyzer, evaluation procedures, and
performance test procedures.

Analysis of the Emission Inspection Analyzer, W. Clemmens,
EPA-AA-IMS-80-5-A, PB 81 153 496, September 1980.

This report in this three-part series distinguishes between
the "repair" and “inspection” analyzers by explaining the
different roles each plays in the I/M process. It includes
discussions on minimum quality analyzers, the inspection
analyzer, and I/M program considerations to be weighed in
choosing analyzer specifications.

© =33-


AIR QUALITY
(see also I/M Effectiveness)

Air Toxics Emissions from Motor Vehicles, P.M. Carey,
EPA-AA-TSS-PA-86-5, Sept 1987.

The report is designed to be a compilation of available
information on emission levels of potentially carcinogenic
substances from motor vehicles. While earlier EPA reports
discuss air toxics emissions in general, their main emphasis
was not mobile sources.

Statistical Analysis of the Effect of Inspection and

Maintenance on Carbon Monoxide Air Quality in Portland,
Oregon, G.C. Tiao, J. Ledolter, and G. Hudak,

EPA-460-3-91-016, 15 May 1981.

This study evaluated monthly, daily and hourly ambient carbon
monoxide (CO) averages for the years 1970 - 1979 from four
Portland, Oregon monitoring sites (where I/M is operating)
and one Eugene, Oregon site (where there is no I/M). This
data was statistically compared to changes in traffic volume,
meteorology and the long term effects of the Federal vehicle
emission standards.

The results of these analyses indicate that significant
reductions in carbon monoxide (CO) air quality levels can be
attributed to the biennial I/M program in Portland. In the
years when most Portland vehicles received their inspections
(1976 and 1978), ambient CO concentrations were 8% to 15%
lower than they would have been without the I/M program.
Based on this finding, EPA has calculated that the ambient CO
improvement due to an annual I/M program that inspected every
subject vehicle each year would have been 10% to 19%.

Natural Sources of Ozone: Their Origin and Their Effect on
Air Quality, EPA-AA-IMS-AQ-80-2, March 1980.

There are two main natural sources of ozone: 1) the
stratosphere, and 2) biogenic hydrocarbons (from plants)
which react ‘in sunlight with nitrogen oxides to form ozone.
On the average, natural sources of ozone contribute about
0.02 to 0.05 parts per million to the ambient background
level. The National Ambient Air Quality Standard for ozone
is a one-hour standard of 0.12 ppm. Man-made sources
contribute most of the ozone in urban areas where the
standard is being exceeded.

-15-


Investigations Relating to In-Use Emissions of 1980 and Later

Vehicles, Energy and Environmental Analysis, Inc., September,
1984.

EEA's previous analysis of the Arizona I/M program (Analysis
of Inspection/Maintenance Data from The Arizona Program, EEA,
Inc., April 1983.) is updated with an additional 12 months
(July 1982 through June 1983) of test data, and expanded to
include 18 months (January 1982 through June 1983) of test
data from the Seattle I/M program. The study spans five
groups of late-model vehicles: 1980 GM LDV's, 1981 LDV's and
LDT's, and 1982 LDV's and LDT's. The bulk of the report is
devoted to extensive data tables and regression analyses of
the performance of late model vehicles. The text contains a
discussion of the development of the data base, and an
investigation of failure rate trends at successive annual
inspections and as a function of accumulated mileage. Among
EEA's conclusions are, 1) that failure rates generally
increase linearly with accumulated mileage, and 2) that
vehicles which fail the initial test of one annual inspection
have a substantially increased probability of failing
subsequent inspections.

Emission Control Technology and Strategy for Light-Duty
Vehicles: 1982-1990, EEA, Inc., April 1984.

This report provides a detailed forecast of gasoline-fueled
light-duty vehicle emission. control systems for the years
1982-1990. The emission control technology mix is broken
down in detail for each major manufacturer, as well as for
the new car fleet as a whole. The report also discusses the
emission control system malperformance strategies used by
each manufacturer.

Analysis of Inspection/Maintenance Data From the Arizona
Program, Energy and Environmental Analysis, Inc., April 1983.

Short Test Results on 1980 and 1981 Passenger Cars From the

Arizona Inspection and Maintenance Program, T. Darlington, R.
Crawford, M.Sashihara, Unpublished SAE paper.

The purpose of this study is to better understand the
performance of new emission control system designs under
I/M. Data for over 16,000 1980 and 1981 cars inspected in
the Arizona I/M program were analyzed to determine failure
rates, repair types, and repair costs. The results show that
the initial failure rate was about 1.0% for the 1980 vehicles
and 2.5% for 1981 cars. The pass rate on the first retest is
over 70% and moved up to 80-90% on subsequent retests.
Repair cost data for these vehicles averaged around $38. The


PUBLIC AWARENESS

Public Opinion Polls for Inspection and Maintenance Programs:
Some Technical Considerations, R. DePietro, EPA-AA-IMS-82-1,

PB 83 149 534, January 1982.

High quality, scientific polls require careful planning and
attention to numerous details. There is considerable
flexibility in the development and implementation of a poll.
The decisions which are made about sample selection and size,
the choice of a polling methodology, questionnaire design and
wording, and the use of quality control measures will
ultimately affect the cost and accuracy of polling results.

The purpose of this report is to provide state and local
governments with information that could be used in the
planning and implementation of public opinion polls,
especially those with respect to I/M programs. The report
discusses the purposes of polls and how to effectively plan
one. Technical issues addressed include: survey design;
sample selection and size; accuracy of data; and, data
analysis, interpretation and presentation. General informa-
tion on the cost of various polling options and determining
who should conduct a poll is presented.

Guidance on I/M Public Awareness Budgets, R. DePietro,
EPA-AA-IMS-81-25, PB 82 155 490, December 1981.

The report, “Public Awareness Guidance for Inspection and
Maintenance Programs", issued by EPA in January 1981,
discusses in considerable detail a step-by-step process for
developing a public awareness plan. An important part of
that planning process includes the development of a viable
budget. The budget should be prepared to ensure that funds
are spent in accordance with public awareness goals and
plans; that proposed activities are supported at sufficient
funding levels to achieve their objectives; and that funds
are allocated to maximize their potential effectiveness.

This guidance is intended to assist state and local agencies
to identify the typical items that could be included in their
annual I/M PA budget. It provides explanation of these items
and a typical range of costs for them based on the experience
of planned or operating programs around the country, and on
estimates provided by advertising agency representatives. A
sample I/M public awareness budget is also included.

-30-


Quality Standards (NAAQS) for these pollutants. EPA has
recently proposed requirements applicable to these SIP calls
(52 FR 45044, November 24, 1987), and many affected areas
will need to estimate current and future year motor vehicles
emissions. Use of alternative fuels and fuel blends is
likely to be part of future scenarios that will be examined
in many areas.

Tech 4 Credit Model: Estimates for Emission Factors and

Inspection and. Maintenance Credits for 1981 and Later
Vehicles for MOBILE3, D.J. Brzezinski, EPA-AA-IMG-85-6,

Oct 1985.

The report provides the basis for the equations used in
MOBILE3 to predict the emission levels of 1981 and newer
gasoline powered light-duty passenger vehicles. This was
done by characterizing the performance of vehicles in the
Emission Factor data base separately for several technology
types, such as fuel-injected versus  carbureted, and
recombining the technologies based on projected mixed to
produce estimates of emissions of future model years. The
Tech IV Credit Model is the computer software developed to
calculate the MOBILE3 emission factor estimates. In
addition, the model was used to estimate the emission
reductions due to Inspection and Maintenance (I/M) programs
for these vehicles. The emission levels of vehicles in the
sample identified by various test type and cutpoint
combinations were reduced to reflect repairs due to the I/M
program. After combining the repaired and unrepaired vehicle
emission levels, the overall reduction from the non-I/M base
case is expressed as a fraction of the base case. This
reduction fraction is scored in MOBILE3 and used to estimate
fleetwide reductions due to I/M programs.

Multiple Stringency Verison of MOBILE3 Users Guide.
D.J.Brzezinski, EPA-AA-TSS-IM-85-2, Apr 1985.

MOBILE3, as with all of the EPA mobile source models, uses a
single stringency to identify the first year failure rate of
Tech I (pre-catalyst) and Tech II (oxidation catalyst)
vehicles in. the Inspection and Maintenance (I/M) program to
be modeled. This single number most often covers a wide
range of technologies and vehicle classes when applied to an
I/M program which inspects many model years and all vehicle
types. Unless the outpoints used are carefully balanced, the
actual failure rate may vary greatly from model year to model
year and vehicle class to vehicle class. This single
stringency input was meant to reduce the amount of input
information necessary to model an I/M scenario. It is

-27-


1981 dollars). The cost-effectiveness of I/M compares
favorably with that of stationary source control measures,
traffic controls, and transit improvements.

Data_Summary Tables on the Effects of Specific Maintenance
son the Emissions from In-Use Light Duty Vehicles

Failing Idle Test Cutpoints, D. Brzezinski, EPA-AA-IMS-80-11,
PB 81 187 726, December 1980.

The tables in this report were compiled from data selected
from the computer data records from several testing
programs. Except in the Portland Study NOx Analysis Tables,
only vehicles which received at least one repair and retest
sequence were selected from the testing programs for summary
in this report. No effort was made to create a sample which
would contain a specific mix of model years or vehicle
types. Caution should be used in extrapolating any measured
changes from this report to real world changes which might be
observed in an in-use fleet.

Update _on EPA's Study of Oregon Inspect ion/Maintenance Program
J. Rutherford and R. Waring, APCA Paper #80-1.2, 24 June 1980.

Analysis of Oregon's Inspection/Maintenance Program,
J. Becker and J.Rutherford, APCA Paper #79-7.3, 25 June 1979.

EPA conducted an extensive evaluation of the Portland, Oregon
Inspection and Maintenance program. The Oregon inspection
(idle) test identified 55% of all vehicles emitting above the
federal carbon monoxide (CO) or hydrocarbon (HC) standards.
This 55% accounted. for 80% of the CO and HC emissions in
excess of the federal standards. Maintenance performed by
Portland area mechanics resulted in a 47% reduction in CO
emissions and a 42% reduction in HC emissions. The average
cost of maintenance was $22, with over half of the repairs
costing less than $14. In a comparison with an area where
inspections are not performed (Eugene, Oregon), average CO
emissions for the Portland fleet were 36% lower than fleet
emissions for Eugene during the year following maintenance.
Hydrocarbon emissions were 20% lower.

Testing Support for Evaluation of Inspection/Maintenance

Issues (Test Groups No. 9 & 10) H. Ashby 1980, PB 81 203 168;
See also PB 81 123 499.

The intention of Test Group No. 9 was to evaluate exhaust
emissions from vehicles in Portland, Oregon, which are
subject to a state inspection and maintenance (I/M) program
with those in Vancouver, Washington, which was not subject to
I/M. Fifty 1976 and fifty 1978 model year vehicles were


carburetor adjustments, that ignore manufacturer specifica-
tions and rely on idle CO readings on an emission analyzer,
are effective. Further considerations included whether a
universal target idle CO level could be used, and what
additional repairs are necessary to pass the I/M test. 83%
(29 out of 35) of the 1976/78 cars from Vancouver,
Washington, that received simple carburetor adjustments to a
universal idle CO target level of 0.2%, were able to pass the
Oregon emission inspection. Average FTP HC emissions of all
vehicles were reduced 40% and FTP CO emissions were reduced
58%. Additional maintenance performed on the six failing
vehicles increased the average reduction for the 35 vehicles
to 47% for HC and 71% for CO. Average city fuel economy
improved 2.5% while highway fuel economy was reduced 0.4%.
Fuel economy improvements in failed vehicles alone were 3.2%
city and 7.5% highway after the simple carburetor adjust-
ment. Additional maintenance brought average fuel economy
improvements up to 8.3% and 9.2%, respectively. In
conclusion, the study results indicate that the average
reductions in FTP HC and CO emissions from specific idle CO
adjustments can be as large as idle adjustments using
manufacturer specifications. Substantial emission reductions
were achieved by using a simple carburetor adjustment — to a
universal idle CO target.

Emission Reductions From Inspection and Maintenance:

Vancouver Versus Portland Snapshot, R. Michael,
EPA-AA-IMS-81-18, PB 82 119 033, August 1981.

This report presents findings from a comparison of similar
cars in Portland, Oregon and Vancouver, Washington. The
purpose of this study was to compare the emissions from
vehicles subject to the I/M program with emissions from
non-I/M vehicles. A group of 100 1976-1978 model year
vehicles of similar vehicle type and odometer readings were
tested, using the FTP, from each of the two cities.

For the 1976 model year, Portland I/M vehicles had FTP HC
emissions 27% lower and CO emissions 22% lower than the
non-I/M vehicles. The results for both I/M and non I/M
cities agree closely with predictions from MOBILE2. The 1978
model year vehicles in Vancouver were unexpectedly and
unexplainably clean (contrary to results from other testing),
having emission levels near that of the Portland vehicles.

Update _of Cost-Effectiveness of Inspection and Maintenance,
7. Darlington, EPA-AA-IMS-81-9, PB 81 214 108, April 1981.

The cost-effectiveness of an inspection and maintenance
program for a typical urban area over a five-year period
(1983-1987) would be $581/ton for HC and $53/ton for CO (in


Statistical Analysis of Multiple Time Series Associated With
Air Quality Data: New Jersey CO Data, J.Ledolter, et al.,
Report #529, June 1978* [Available from G. Tiao, University
of Wisconsin, Dept. of Statistics, Madison, WI 53706]

From 1971 to 1977, carbon monoxide levels monitored at seven
stations in New Jersey decreased significantly. The average
reduction is approximately 28%. This reduction is attributed
to the progressively stringent federal emission standards, to
state programs such as the car inspection and maintenance,
and to the oil and energy crisis. The above conclusions are
not significantly altered when meteorological variables are
factored into the model.

-16-


NEW TECHNOLOGY VEHICLES
(see also Emission Factors)

Inspection and Maintenance of New Technology Vehicles in
Maryland. L.C. Landman, EPA-AA-TSS-IM-86-06 Sept, 1986.

The report summarizes an effort to study new technology
cars. The goal was to recruit and test approximately 100
late-model year cars which failed the Maryland Inspection and
Maintenance (I/M) program. The goal was to determine the
nature of in-use emission problems on 1981 and later vehicles
which fail I/M short tests and the types of repairs needed to~-
reduce their emission levels to near or below the new car
standards.

Inspection and Maintenance of New Technology Vehicles in
Washington, D.C. Technical Support Staff, J. Adler,

EPA-AA-TSS-85-07, July 1985.

The report presents the results of an emission testing
program which was conducted for EPA in Washington, D.C.,
under contract. In the test program, 1980 and 1981 model
year vehicles which failed the Inspection and Maintenance
(I/M) test in Washington, D.C. were given two or three series
of emissions tests. Each series included a Federal Test
Procedure (FTP), a Highway Fuel Economy Test, and the
following short tests: 50 mph cruise, four-mode idle, engine
restart idle, and loaded two-mode. In June, 1984, EPA became
aware of some quality control problems which were evident at
the D.C. inspection stations. These problems may have caused
some of the vehicles which were participating in the project
to be inappropriately failed during the initial inspection or
inappropriately passed during the reinspection. Analyses
described in the report evaluate the decisions made by the
inspection lane, and compare the effects of I/M on the whole
group of cars with those of subgroups that have had suspect
cases removed.

Fact Sheet: Inspection and Maintenance for “New Technology"
Vehicles, FS-70, EPA-OMSAPC-45513

This fact sheet discusses issues dealing with I/M for new
technology vehicles (i.e., 1981 and later model year
vehicles) in a question and answer format. The report
describes the differences between new technology and previous
technology for emission control systems. The report also
examines the emission control performance of new technology
vehicles, the types of emissions-related maintenance problems
common to these vehicles, and the applicability of I/M to
these vehicles.


TAMPERING AND MISFUELING

Motor Vehicle Tampering Survey - 1989, May 1990

Motor Vehicle Tampering Survey - 1987, August 1988

Motor Vehicle Tampering Survey - 1986, September 1987

Motor Vehicle Tampering Survey - 1985, November 1986

Motor Vehicle Tampering Survey - 1984, September 1985
Motor Vehicle Tampering Survey - 1983, August 1984

Motor Vehicle Tampering Survey - 1982, EPA-330-1-83-001,
April 1983.

EPA conducts surveys in 10-12 different cities each year to
determine the nature and extent of tampering and misfueling.
Surveys are done in areas with I/M programs as well as
non-I/M areas. The reports describe the findings of the
surveys and any significant trends that are evident from the
data. Tampering rates are described on a city-by-city basis,
by component, and in various other ways.

Collection of Lead Poisoned Catalysts in Houston, C.A.
Harvey, EPA-AA-TSS-IM-86-8, Contract EPA-68-03-3192,

Sept 1986.

The report describes project involving the testing of
lead-poisoned catalytic converters in the Houston, Texas,
area. Five lead-poisoned catalysts were collected from motor
vehicles. Various methods to evaluate the conditions of the
degraded catalysts included weight and back pressure
measurements, and x-ray diffraction to define substrate
structure.

Results of Plumbtesmo_Tailpipe Testing on Ten Vehicles

Misfueled with 0.1 gm/gal Leaded Gasoline. E.L. Glover.
EPA-AA-TSS-IM-86-07, Sept 1986.

The report presents the results of a misfueling study done by
automotive Testing Labs under EPA contract. The study was
performed to evaluate the performance of Plumbtesmo brand
lead sensitive paper in detecting the presence of lead on
vehicle tailpipe after the vehicles were misfueled with 0.10
+ 0.02 grams/gal leaded fuel (low lead fuel). The report
also addresses the concern whether the test paper can still
be used in vehicle Inspection and Maintenance programs to
detect the presence of lead deposits resulting from the use
of the reduced lead content of gasoline.

-22-


EPA-420-B-91-100

ABSTRACTS OF I/M TECHNICAL REPORTS AND POLICY

March 1991

NOTICE

Technical drafts do not necessarily represent final EPA
decisions or positions. They are intended to present
technical analyses of issues using data which are
currently available. The purpose in the release of such
drafts is to facilitate the exchange of technical
information and to inform the public of technical
developments which may form the basis for a final EPA
decision, position or regulatory action.

U.S. Environmental Protection Agency
Office of Air, Noise and Radiation
Office of Mobile Sources
Emission Control Technology Division
Technical Support Staff
2565 Plymouth Road
Ann Arbor, Michigan 48105


EPA POLICY: INSPECTION AND MAINTENANCE

Inspection/Maintenance Program 1982 SIP Processing, memo from
Charles Gray to Air and Hazardous Materials Division
Directors, Regions I-X, 12 March 1981.

This memo provides information to assist states and EPA
Regional Offices in the development and review of complete
I/M SIP submittals in accordance with the 1982 SIP policy.
It includes the 1982 I/M SIP Checklist which lists all
elements needed for the I/M SIP submittal.

Approval of 1982 Ozone and Carbon Monoxide Plan Revisions for

Areas Needing an Attainment Date Extension, final policy, (46
Federal Register 7182), 22 January 1981.

The Federal Register Notice specifies the 1982 SIP require—
ments for states that have received an extension of the
attainment date for carbon monoxide (CO) or ozone. The I/M
portion of the SIP must contain program elements including
inspection test procedures; emission standards; inspection
station and inspector licensing requirements; emission
analyzer specification and maintenance/calibration
requirements; recordkeeping and record submittal require-
ments; quality control, audit, and surveillance procedures;
procedures to assure that non-complying vehicles are not
operated on the public roads; any other official program
rules, regulations, and procedures; a public awareness plan;
and a mechanics training program if additional emission
reduction credits are being claimed for mechanics training.

Questions on Inspection/Maintenance, memo from M. Walsh to
Air and Hazardous Materials Division Directors, Region I-xX,
19 January 1981.

This memo answers common questions regarding the application
of the elements of the 1978 I/M policy. It covers emission
reductions required for I/M (RACT), inspection procedures,
equipment and quality assurance, assurance of compliance by
vehicle ownérs, data collection and reporting, and emission
credits for mechanic training.

-45-


cost-effectiveness are not possible. A reasonable upper
limit for repair cost of 1980 and later vehicles is estimated
at $105 per failed vehicle.

Derivation of I/M Benefits for Pre-1981 Light Duty Vehicles
for Low Altitude, Non-California Areas, J. Rutherford,

EPA-AA-IMS-82-3, PB 83 145 102, June 1982.

This report presents the derivation of the I/M emission
reduction benefits for pre-1981 model year vehicles (non-
California, low altitude) which were prepared for use in
EPA's emission factors model, MOBILE2 (corrected version).
Included is a discussion of the I/M credits for pre-1981
vehicles included in MOBILE2, a comparison of the credits
used in MOBILE2 versus MOBILE1, a step-by-step analysis of
the simulation model with formulate and parameters, and a
listing of the Fortran IV source code for the program which
produced the credits.

Inspection and Maintenance for 1981 and Later Model Year
Passenger Cars, D. Hughes, SAE 810830, June 1981.

New technology vehicles are vulnerable to malmaintenance or
parts failure and tampering, resulting in emissions grossly
exceeding the design standards. Even though only a small
percentage of vehicles experience failures, these few
vehicles contribute the majority of the entire new technology
fleet's CO emissions and a large share of the new technology
fleet's HC emissions.

The fuel economy penalty for new technology vehicles
operating in a full-rich mode (i.e., too much fuel being
supplied to the engine in relation to the amount of air being
supplied resulting from any of a variety of malfunctions) is
quite large: approximately 15%. Therefore, individual
failed vehicles will enjoy substantial fuel savings ($135 per
year) subsequent to proper repair.

Evaluation of the Applicability of Inspection/Maintenance
Tests on a Chevrolet Camaro Z-28, B. Smuda, EPA-AA-IMS/80-10,

PB 81 188 757, April 1981.

This report presents test results which were gathered to
determine the suitability of existing I/M short tests on a
Chevrolet car with a computer based emission control system.
This car had a microprocessor based engine control system
with a dual bed catalyst. After suitable baselines were
established, various components were made inoperative in the
emission control system. Complete FTP, HFET, and I/M tests
were run for each vehicle condition. Also an on-board system


most common repair reported was to the air fuel mixture and
the idle speed. Dwell and timing adjustments were the next
most prominent repair type.

Disablement Testing of 1981-1982 Model Year Vehicles With

Closed-Loop Emission Control Systems, R. Michael,
EPA-AA-TSS-82-5, PB 83 144 568, September 1982.

This report presents the results of emission control system
disablement testing of recent model year vehicles. Starting
in 1981, Federal vehicles were designed to meet more
stringent emission standards such that most employed computer
controls utilizing exhaust emission feedback. This study was
designed to test four vehicles equipped with throttle body
fuel injection. The results showed that several types of
disablements, such as sensor disconnections or EGR vacuum
line disconnections, which might result from tampering, cause
very high FTP emissions. HC emissions often were 10 times
certification standards and CO emissions were 20 or more
times greater. Short tests were able to identify about 95%
of the excess FTP emissions.

In-Use Emissions of 1980 and 1981-Passenger Cars: Results of
EPA Testing, P. Lorang, J. White III, D. Brzezinski,

SAE 820975, August 1982.

This paper presents results from EPA testing of 1,328
randomly selected passenger cars from the 1980-1982 model
years in-use in Los Angeles and other low altitude areas.
The primary purpose was to examine emission characteristics
of various control technologies, provide information for
improvement of I/M programs, and identify potential failure
areas in advanced emission control systems. Each vehicle was
tested in "as received" condition using the 1975 Federal Test
Procedure, the Highway Fuel Economy Test and several short
cycle tests developed for use in I/M programs. In addition,
underhood inspections of emission related components were
conducted and certain vehicles were selected for maintenance
(generally a major tune-up). These "restored" vehicles were
then retested using the same sequence.

The results show that new technology vehicles are capable of
maintaining very low emission levels but they may also have
extremely high levels due to defects, deterioration and
tampering. The results also show that the I/M short tests
are effective for 1980 and later vehicles and that it is
important to use I/M cutpoints of 220 ppm HC and 1.2% CO to
achieve maximum benefit from I/M. Further, the results
indicate that failure rates and error of commission rates
will be lower among 1980 and later vehicles than pre-1980
vehicles. Firm conclusions regarding repair costs and I/M


I/M_ Network Type: Effects on Emission Reductions, Cost and
Convenience, E. Tierney, EPA-AA-TSS-I/M-89-2, January 1991.

Two basic types of I/M systems exist: 1) inspection and
retest at high volume, test-only lanes (a centralized
network), and 2) inspection and retest at privately-owned,
licensed facilities (a decentralized network). This report
examines how I/M network choice affects program costs,
convenience, and overall emission reductions. The report is
based on operating results from I/M programs across the
country. Significant factors include the design of test
procedures, occurrence of improper testing, resources
necessary for and effectiveness of quality assurance and
quality control, and the incorporation of more sophisticated
I/M technology, especially in light of the recent Clean Air
Act Amendments. The report concludes that centralized I/M
networks will usually offer greater emission reduction
benefits at a lower cost than decentralized networks.

A_Discussion of Possible Causes of Low Failure Rate in
Decentralized I/M Programs Eugene J. Tierney,
EPA-AA-TSS-I/M-87-1, January 1987.

This technical report reviews six possible explanations for
low reported failure rates in manual, decentralized I/M
programs. The report analyzes and discusses random roadside
idle survey data, reported I/M program data and data
collected during audits of I/M programs. The data indicate
that five of the explanations: quality control,
fleetmaintenance, differences in fleet mix or emission
standards, anticipatory maintenance, and  pre-inspection
repair, do not sufficiently explain low reported failure
rates. The report concludes that the major. problem
contributing to low reported failure rates in decentralized,
manual I/M programs is improper inspections by test station
personnel.

Guidance on Quality Control for Inspection/Maintenance
Programs, EPA-460/3-82-006, PB 82 254 335, Radian
Corporation, June 1982.

A crucial aspect of an effective I/M program is the quality
control procedures and processes incorporated into it.
Accurate inspections are key to identifying gross emitters
without error. Therefore, quality control of the emission
analyzers, inspection procedures and audit procedures play a
major role in the overall success of the program. This
report discusses the planning and development of quality
control procedures for each of these three elements. The
report details quality control for emission analyzers

-41-


memo describes this program and how it can be made available
to interested states.

MOBILE2 I/M Credits for California, memo from C. Gray to
L. Giersch, Region IX, 20 March 1981.

Due to the difference in new vehicle emission standards
between California and the non-California fleet and the
resultant differances in emission control technologies, the
question arises. as to whether I/M credits developed for the
federal fleet, as used in MOBILE2, are directly applicable in
California. This memo reviews an analysis of this question
and presents I/M emission benefits for use in the 1982 SIP.

User's Guide to MOBILE2 (Mobile Source Emissions Model),
PB 81 205 619, February 1981.

A_Comparison of MOBILE1 and MOBILE2, T. Cackette, P. Lorang,
J. Wallace, EPA-AA-IMS-81-6, December 1980.

MOBILE2 is a computer program that calculates emission
factors for hydrocarbons (HC), carbon monoxide (C0), and
oxides of nitrogen (NOx) from highway motor vehicles. It
estimates emission factors for any calendar year between 1970
and 2020. Compared to MOBILE1, MOBILE2 incorporates several
new options, calculating methodologies, emission factor
estimates, emission control regulations, and internal program
designs. The program uses the calculation procedures and
emission factors presented in Compilation of Air Pollutant
Emission Factors: Highway Mobile Sources, March 1981 (EPA
460-3-81-005).

-29-


Inspection/Maintenance Policy, memo from D. Hawkins to
Regional Administrators I-X, 21 February 1979.

This memo discusses criteria for granting extensions beyond
the July 1, 1979 deadline for obtaining state enabling
legislation for I/M programs and sets a uniform implemen-
tation date of December 31, 1981 for decentralized programs
and December 31, 1982 for centralized programs.

Inspection/Maintenance Policy, memo from D. Hawkins to
Regional Administrators I-X, 17 July 1978.

This memo indicates the elements EPA considers to be part of
a minimally acceptable I/M program. It includes information
on what should be included as part of an I/M SIP submittal,
the I/M implementation schedule and deadlines, authority to
implement I/M, geographic coverage, emission reductions
needed for I/M, and minimal program requirements. for
centralized and decentralized programs. :

-46-


possible for MOBILE3 to use a separate stringency for each
model year of each vehicle class. The only barrier has been
the need to modify the input stream and appropriate
subroutines to accept and utilize user supplied information.
Such modifications have been done and the results are
described in this report.

Modifications to MOBILE2 Which Were Used by EPA to Respond to
Congressional Inquiries on the Clean Air Act, EPA-AA-IMS-82-2
PB 83 137 414, May 1982.

This report provides the modifications (generally known as
MOBILE2.5) used by EPA to respond to Congressional inquiries
regarding the impacts of changes in motor vehicle emissions.
The modifications represent EPA's revised estimates of
emissions from certain vehicle classes under current
statutory standards, as well as expected differences in
administratively determined standards from those assumed in
the original version of MOBILE2.

MOBILE2 Errata, memo from C. Gray to Air and Hazardous
Materials Division Directors, Region I-X, 22 April 1982.:

Use_of MOBILE2 for the 1982 SIP Submittal, memo from C. Gray
to Air and Hazardous Materials Division Directors, Region
I-X, 11 December 1981. .

MOBILE2_ I/M Credits for High Altitude Areas, memo from
C. Gray to Air and Hazardous Materials Division Directors,

Region 8-10, 4 August 1981.

Due to the differences in vehicle operation at high-altitude
versus low-altitude, the standard I/M credits contained in
MOBILE2 (developed for low-altitude areas) are not the most
appropriate for use in evaluating the effects of I/M in high
altitude areas. An alternate set of I/M credits has been
developed for use in MOBILE2 for high altitude areas. This
memo explains the basis for these changes and provides
composite I/M benefits for high altitude areas.

MOBILE2 I/M Credits for Scheduled Failure Rates, memo from
T. Cackette to Air Branch Chiefs, Regions I-X, 3 June 1981.

This memo contains information regarding special purpose
MOBILE2 I/M credits. ‘In I/M programs with permanently fixed
cutpoints, _ MOBILE2 accurately provides the associated
emission credits. In programs in which the cutpoints may be
changed, a new computer program is available which estimates
I/M benefits for any given schedule of failure rates. This

-28-


recruited from Vancouver and tested. Matching vehicles were
then recruited from Portland and tested. The intention of
Test Group No. 10 was to evaluate the effect of specific
maintenance tasks on emissions from vehicles which have high
emission levels as. determined by a state I/M program.
Thirty-five vehicles from the Vancouver, Washington, area
which failed the Oregon State Inspection Test as part of the
testing required for Test Group No. 9 were selected for this

group.


vehicles: 1.0% CO and 200 ppm HC (hexane) for the two speed
idle test, 1.2% CO and 220 ppm HC for the idle and
loaded-mode procedures. The regulations provide
manufacturers the option of requesting alternate standards
and procedures if the general provisions are not appropriate
because of special designs, unique technology and other
similar factors.

Analysis of Propane Gain Used_as_a Screen _on the Portland
Element III Sample, D. Brzezinski, EPA-AA-IMS-PS-80-3,

PB 80 175 581, March 1980.

Propane gain values have been collected from 292 Portland
Element III (1975-77 model year) vehicles along with
as-received FTP and idle test emission measurements. This
data is used here to compare the expected failure rate,
errors of commission, and the amount of FTP excess emissions
identified if one of two sets of idle values or one of four
propane gain values had been used as a cutpoint to screen the
vehicles in the sample with high emissions.

Analysis of In-House I/M Testing of a Three-Way Chevrolet
Citation and a Three-Way Dodge Aspen, EPA-AA-IMS-ST-80-1,
PB 80 139 934, January 1980.

This report is an analysis of the effectiveness of I/M type
“short tests" in identifying grossly emitting vehicles. This
report examines the question for two vehicles equipped with
the technology to be introduced nationwide in 1981. This
technology incorporates a high degree of engine control
through the use of sensors, actuators, and an on-board
computer, and allows the simultaneous conversion of HC, CO,
and NOx in a three-way catalyst. In a- testing program
performed in-house, a 1980 Chevrolet Citation and a 1979
Dodge Aspen were selectively disabled to simulate possible
in-use vehicle conditions. A wide range of testing was
performed at each condition including FTP testing and I/M

short tests. In this report, the FTP results are compared to
the results of two I/M tests to examine their effectiveness
in identifying vehicles with gross FTP emissions. Each
vehicle is first discussed separately and then an overall
comparison is given. Full data sets for the two vehicles may
be obtained from the reports referenced at the end of the

report.

-19-


GENERAL

Inspection/Maintenance Program Implementation Summary,
updated quarterly.

This document summarizes essential characteristics of every
required I/M program in the country. These characteristics
have been derived from statutes and/or rules and regulations
promulgated by the state or locality. The list includes the
names of states, cities and counties implementing I/M and
lists the SIP-approved implementation dates. It indicates
whether the program is centralized or decentralized and what
type of enforcement mechanism is planned or being used. Test
fees are listed along with the cutpoints for light duty
vehicles.

Inspection/Maintenance Fact Sheet, FS-67, August 1981.

The question and answer format of this fact sheet provides a
brief background on the I/M program. Key issues are covered,
including what I/M is, how it works, public acceptance, costs
and cost effectiveness, emission reductions, air quality
impacts, fuel economy benefits, and warranties.

Health Effects of Carbon Monoxide and Ozone, EPA-AA-IMS-81-8,
PB 82 114 265, July 1981. :

This report summarizes the information known about the health
effects of carbon monoxide (CO) and ozone (0;), and how
that information is used by EPA to set National Ambient Air
Quality Standards. In addition, this report discusses the
sources most likely to contribute to high levels of CO and
0, and how EPA control programs. will reduce emissions from
these sources in the future. The information in this report
is presented in a question and answer format.

Compilation of Inspection/Maintenance Facts and Figures,
J. Armstrong and E. Tierney, EPA-AA-IMS-81-15, PB 82 112 400,

June 1981.

This report compiles and summarizes the latest technical
information available from laboratory studies, surveys and
field investigations of operating I/M programs for the use of
policy makers and planners. Issues addressed include: air
quality, the role of I/M, emission reductions, fuel economy,
economic costs, cost effectiveness, public attitudes, and new
technology vehicles. The facts and figures in this report
have been gathered from various technical reports referenced
at the end of the document.

-36-


A Survey of Operating Inspection/Maintenance Programs,
R. Klausmeier and D. Kirk, Radian Corporation, 18 April 1980,

PB 81 174 112.

This report provides information on currently operating I/M
programs as an aid to state/local agencies which are
presently planning the implementation of I/M. The report is
divided into two sections. The first section is a narrative
description of the programs. The second section contains
tables that summarize the different technical and administra-
tive aspects of the programs. The topics discussed in the
report include a general descriptions of each operating
program, cutpoints, data collection and analysis, quality
assurance, training, public information, and air quality
improvements.

Requlated and Unregulated Exhaust Emissions from Malfunction-
ing Three-Way Catalyst Gasoline Automobiles, C. Urban,

Southwest Research Institute, PB 80 190 804, January 1980.

This report describes the laboratory effort to characterize
regulated and unregulated exhaust emissions from three-way
catalyst-equipped gasoline automobiles operating under
malfunction conditions. Three automobiles were evaluated
over three driving schedules in the unmodified configuration
and in four engine and/or emission control system malfunction
configurations. Exhaust emission constituents measured, in
addition to the current regulated emissions, include:
particulate sulfates, aldehydes, sulfides, amines, metals,
and several additional elements and compounds. Additional
evaluations, in each of the configurations, involved the
measurement of regulated emissions over four short-cycle
procedures.

Reducing Air Pollution from Motor Vehicles — Developments in
the In-Use Strategy, T.Cackette, APCA paper 79-7.1, June 1979.

This paper discusses the current Federal Motor Vehicle
Emission: Control Program (FMVECP) which includes car
certification, selective enforcement audit (assembly line
testing) and recall, which are federal responsibilities, and
inspection and maintenance (I/M), which is a state or local
responsibility. The first three elements of the FMVECP
assume that. vehicles will maintain their new car emission
levels. Studies have shown this not to be the case due to
maladjustments and lack of maintenance. The paper concludes
that I/M is needed to identify those cars with excess
emissions, and to ensure necessary repairs are performed.

-37-


Evaluation of Applicability of a Lead-Sensitive Test Paver as
a_Diaqnostic Tool for Detecting Habitual Misfueling of

Catalyst-Equipped Motor Vehicles, B. Smuda, EPA-AA-IMS-80-6,
PB 81 179 012, July 1980. .

Use of leaded fuel in catalytic converter equipped vehicles
(misfueling) adversely affects the ability of the catalyst to
reduce undesirable emission levels. A quick reliable method
of detecting habitual misfueling would be a valuable
diagnostic tool for detecting lead poisoned catalysts.
PLUMBTESMO is a lead sensitive test paper that according to
its manufacturer's product literature can be used to detect
metallic lead. When applied to the inside surface of a
tailpipe containing lead deposits, the originally white test
paper develops red spots and streaks within a few minutes.
This test can be applied to cold or hot tailpipes. The
reaction appears to take place in less time when the tailpipe
is hot. The I/M staff has conducted an evaluation of
PLUMBTESMO on a sample of vehicles in the Ann Arbor area.
This report describes that evaluation and its results.

-25-


I/M EFFECTIVENESS
(see also Air Quality)

Exhaust and Evaporative Emissions of High Mileage Taxicabs

and Passenger Cars, Technical Support Staff,
EPA-AA-TSS~PA-85-8, Feb. 1985.

The report gives the results of exhaust and evaporative
emissions tests. Southwest Research Institute performed on 27
vehicles. Test cars were selected randomly from a
registration list of all 1981 passenger cars in Bexar County,
Texas (which includes the greater San Antonio area and some
surrounding surburban and rural areas). Seven of the 27 cars
underwent restorative maintenance after baseline testing
(replaced canister or gas cap) and evaporative emissions were
measured again after maintenance. The results of the tests
are summarized in the report.

Exhaust and Evaporative Emissions of High Mileage Passenger
Cars. C.A. Harvey, and B. Michael. EPA-AA-TSS-PA-85-1,
Feb 1985.

Prepared in cooperation with Southwest Research Inst., San
Antonio, TX

This report gives the results of exhaust and evaporative
emission tests Southwest Research Institute performed on 27
motor vehicles. Test cars were selected randomly from a
registration list of all 1981 passenger cars in Bexar County,
Texas (which includes the greater San Antonio area and some
surrounding suburban and rural areas). Seven of the 27 cars
underwent restorative maintenance after baseline testing
(replaced canister or gas cap) and evaporative emissions were
measured again after maintenance.

Emission Effects of Inspection and Maintenance at Cold
Temperatures, T. Darlington, EPA-AA-IMS-81-24, PB 83 136 556,

revised October 1982.

This report discusses the potential effectiveness of
Inspection and Maintenance (I/M) programs at reducing .cO
emissions from vehicles operated at cold temperatures. EPA
has extensively studied the effectiveness of I/M for reducing
emissions at 75°F, and has shown that I/M is capable of
reducing CO emissions on failed vehicles by about 50% at
75°F. At warm temperatures maladjustment of idle mixture is
the most common cause of high CO emissions. At colder
temperatures the operation of choke systems causes high CO
emissions. However, vehicles which have maladjusted idle
mixture may emit more CO in cold temperatures than vehicles


Centralized I/M Program Cost Calculation Worksheet, IMS-005-
CW-1, August 1979.

These worksheets are designed to enable I/M _ program
administrators to project total costs of I/M programs at
early stages of planning. The factors involved in initial
and annually recurring costs are systematically organized to
compute an annual inspection fee which will cover all program
costs for the total length of the program.

-44-


including daily and weekly quality control checks,
preventative maintenance, documentation and audits. The
report discusses pre-inspection, during-inspection, and
post-inspection quality control procedures. Finally, quality
control for inspection station auditing is discussed
including checking the performance of equipment, checking
procedures, taking corrective action, and documentation.

The Colorado Experience with Inspection/Maintenance Data
Handling: Machine Readable Forms, National Center for

Vehicle Emissions Control and Safety, Colorado State
University, PB 83 116 814, May 1982.

This document describes the I/M data handling system for the
Automobile Inspection and. Readjustment (AIR) Program operated
by the. State of Colorado. Machine readable forms (also
called optically read or scanned forms) play a key role in
that program's inspection data system. The intended purpose
of this report is to provide detailed descriptive information
for the consideration of other I/M programs. The report
includes information on planning and implementation of the
data handling system and the analysis of data.

Guidance on Data Handling and Analyses. in an
Inspection/Maintenance Program, EPA-460/3-82-007, PB 82 252
974, Radian Corporation, December 1981.

This report provides guidance on the establishment of a data
handling and analysis system for I/M programs. The report
discusses the various uses of data including: evaluating
inspection facility performance, the vehicle waiver system,
and sticker enforcement effectiveness; revising cutpoints;
determining sticker accountability and fee accountability;
quantifying idle emission reductions; and preparing reports.
Details are presented on statistical analysis and sampling
techniques, manual and computer assisted analysis, and ways
of presenting data. The report also contains a discussion of
data collection and handling techniques, including provisions
for assuring quality control in the data base. Finally, the
report discusses the cost of data processing, including
manual, computer assisted and on-line data base management
approaches.

-42-


A question remains, however, about how [/M will work as an
emission control strategy for the generation of electron-
ically controlled, 3-way catalysts vehicles that will be
introduced nationwide in 1981. Data on California models and
several 1981 control systems show that failures of these new
systems, or failure to replace the vehicle's oxygen sensor,
can result in extremely high emission levels. The potential
for the high emission levels to occur in-use are discussed,
and preliminary data on the various: short tests’ ability to
detect high emitting vehicles is presented.

Questions and Answers Concerning the Technical Details of

Inspection and Maintenance, IMS 002/QA-1, PB 301 215,
April 1979.

This report discusses the costs and benefits, implementation
issues, and policy matters related to the I/M program. It
addresses, in a question and answer format, air quality
benefits and emission reductions (FTP, failure rates,
Appendix N, ambient effects, and other factors). It looks at
fuel economy, maintenance costs, and vehicle/engine life. A
discussion of loaded and idle tests, and heavy duty I/M are
included. Repair costs and the factors that affect it are
reviewed, as well as the cost effectiveness of the program.
Various other issues are discussed including mechanic
training, catalytic converters, fuel switching, new
technology vehicles, and warranty regulations. Finally, a
brief overview of I/M program implementation is provided.

~12-


Effects of Inspection and Maintenance Programs on Fuel Economy
IMS-001-FE-1, PB 297 583, March 1979.

The primary goal of inspection and maintenance (I/M) programs
is to improve air quality by reducing emissions from motor
vehicles. Many studies have indicated that I/M programs will
achieve this goal. In addition several studies have
indicated that fuel economy improvement can be expected to
occur as a result of maintenance performed on vehicles
failing an I/M.test. Most studies which have been performed
have looked at pre-1975 model year vehicles and have had
expert mechanics performing the maintenance work. It is the
intention of this report to consider both the results from
past studies and the results from more recent studies in
order to provide EPA's best estimates of fuel economy benefit
which can be attributed to I/M maintenance.

~14-


INTRODUCTION

The purpose of this document is to provide readers with
an easy to use reference to major I/M program technical
reports and policy memoranda. Abstracts of technical reports
are provided for most of the documents listed. Descriptions
are given for technical reports that do not lend themselves
to abstracting. For policy memoranda, descriptions of the
policy issues discussed are provided.

EPA documents are made available to government agencies
and other non-profit groups free of charge, except where
noted. Others should use the National Technical Information
Service to obtain copies. Use the EPA document number when
ordering from EPA and the NTIS publication number (PB#) when
ordering from NTIS. The addresses and phone numbers for
orders are as follows:

National Technical Information Service
U.S. Department of Commerce
Springfield, Virginia 22161

(703) 557-4650

U.S. Environmental Protection Agency
Motor Vehicle Emission Laboratory
Technical Support Staff
2565 Plymouth Road
Ann Arbor, Michigan 48105
(313) 668-4367

ii


MECHANIC TRAINING

A_Study of the Effectiveness of Mechanic Training for Vehicle
Emissions Inspection and Maintenance Programs, R. Michael,
EPA-AA-IMS-81-11, PB 81 219 347, April 1981

This report presents the results of a study performed to
determine if a short practical training course for mechanics
on emissions diagnosis and repair has a supplementary
emission reduction and fuel economy benefit to an inspection
and maintenance program. The study was performed in the
early part of 1980 in Portland, Oregon. The results indicate
that training mechanics in Portland did not produce a
significantly greater emission reduction benefit than if no
training were given. However, a 0.8% improvement in fuel
economy was seen after training due to better repairs.

Training for Inspection and Maintenance Programs, A. Chijner,
EPA-AA-IMS-81-14, PB 81 214 199, April 1981.

This report provides guidance to I/M program administrators
on the development of training for inspectors, auditors,
investigators and mechanics. The report reviews the
experiences and problems encountered by currently operating
I/M programs and provides recommendations on course content
and coordination of training efforts.

-35-


Analysis of Fuel Samples from Baltimore, Detroit and

Philadelphia. Southwest Research Inst., Houston, TX. M.A.
Warner-Selph, c.T. Hare, C.A. Harvey, and J.Adler,
EPA-AA-TSS~PA-86-03, Contract EPA-68-03~-3192, July 1986.

The report describes samples of in-use gasoline analyzed from
a selection of gasoline outlets that were not major
(national) brands. A total of 123 samples were obtained from
three cities; Baltimore, Detroit, and Philadelphia. All
samples were analyzed from Reid Vapor Pressure (RVP),
distillation temperature curve, methanol, ethanol, tertiary
butyl alcohol (TBA), water content, and lead content. In
addition, the ‘Evaporative Index' (EI) was calculated for
each fuel.

Misfueling Emissions of Three-Way Catalyst Vehicles, R. Bruce
Michael, SAE 841354, October 1984.

Twenty-nine in-use automobiles with three-way catalyst
emission control systems were misfueled with leaded gasoline
in order to quantify the emissions effects. The vehicles
used between four and twelve tanks of leaded gasoline. The
leaded gasoline had an average of 1.0 grams Pb per gallon.
Four different test programs were conducted with different
misfueling intensities (rates) and mileage accumulation
schedules. The Federal Test Procedure and several short
tests were conducted at various stages. The results of the
program indicate that vehicle emissions are affected mainly
by the amount of lead passing through the engine and
secondarily by the rate of misfueling.

Anti-Tampering and Anti-Misfueling Programs to Reduce In-Use

Emissions from Motor Vehicles, EPA-AA-TSS-83-10, PB 84 185
222, Dec. 31, 1983.

This report examines the effects of tampering and misfueling
on vehicle emissions and the emission reduction benefits of
anti-tampering/anti-misfueling programs. From 1978 to 1982,
EPA collected tampering/misfueling data from in-use surveys
of over 8,000 cars and trucks. The 1982 survey of nearly
3,000 1975 and later cars is used as the data base for
calculating current and projected (1988) tampering and
misfueling rates. Four specific targets of tampering are
analyzed: catalytic converters, evaporative control systems,
air pumps and PCV. In addition, three misfueling parameters

-23-


TABLE OF CONTENTS

SUBJECT AREA

INTRODUCTION

I/M EFFECTIVENESS

NEW TECHNOLOGY VEHICLES

FUEL ECONOMY

AIR QUALITY

SHORT EMISSION TESTS AND STANDARDS
I/M TEST VARIABILITY

TAMPERING AND MISFUELING
EMISSION FACTORS: MOBILE MODEL
PUBLIC AWARENESS

INSTRUMENT SPECIFICATIONS

I/M CALIBRATION GASES

MECHANIC TRAINING

GENERAL

OTHER FUELS

PROGRAM ADMINISTRATION

EPA POLICY: INSPECTION AND MAINTENANCE

OTHER REPORTS NOT ABSTRACTED

PAGE

ii

13
15
17
21
22
26
30
32
34
35
36
38
40
45
47


OTHER REPORTS NOT ABSTRACTED

Overview of I/M Activities and Issues J. Cabaniss,
EPA-AA-IMG-84-1, February 1984.

Investigations Into The Emissions Effects of Vehicle
Misfueling, J. Armstrong, EPA-AA-IMG-84-3, presented

April 2, 1984.

Size Specific Total Particulate Emission Factors for Mobile
Sources, Robert I. Bruetsch, EPA-AA-TSS-84-4, June 1984.

Emissions of In-Use Vehicles Update on the U.S. Experience,

P. Lorang, EPA-AA-TSS-85-5, September 1984.

-47-


U.S. EPA Public Awareness Guidance for Inspection and
Maintenance Programs, EPA-AA-IMS-81-3, PB 81 213 415,

January 1981.

EPA developed this guidance to assist state and local
agencies in educating the public about I/M. The guidance
recommends a step-by-step planning process to inform the
public about I/M and related issues. Such planning items as
identification of audiences, messages, media techniques and
schedules are addressed. Reference and sample materials that
can be used as models for the production of new materials are
included.

-31-


PROGRAM ADMINISTRATION

EPA Audits of State and Local Inspection/Maintenance

Programs: Federal Fiscal Year 1986, J.M.Cabaniss and J.A.
Houk, EPA-AA-TSS-IM-87-3, March 1987.

The paper reviews the results of EPA's Inspection/Maintenance
Program audits during Federal fiscal year 1986 (FY86). EPA
performed eleven initial program audits and eight follow-up
audits during FY86. The paper highlights design elements
that have proven successful in these programs, and discusses
the applicability of those design elements to other I/M
programs. Also included is the progress that has been made
in resolving operating problems identified in FY86 and
earlier years.

EPA Audits of State and Local Inspsction/Maintenance Programs
P.A. Lorang, J.A. Armstrong and J.M. Cabaniss
EPA-AA-TSS-IM-85-09, June 1985.

Many State and local agencies have implemented vehicle
emissions I/M programs in the last few years. EPA began to
audit these programs in federal FY1984. The audit process
for I/M was developed in conjunction with STAPPA/ALAPCO; the
I/M audit became part of the National Air Audit System in
FY1985. Results of the I/M audits indicate that (1)
enforcement is a problem in some programs with sticker based
enforcement; (2) low reported failure rates are a problem in
many decentralized programs, especially those that use manual
analyzers, and in some centralized, government run programs;
(3) high waiver rates are a problem in some programs, both
centralized and decentralized; (4) analyzer quality assurance
ranges from excellent in centralized, contractor programs to
marginal in decentralized programs with manual analyzers and
in some centralized government run programs; (5) data
analyses are not being effectively used in most programs to
monitor and improve program performance and the performance
of individual inspection stations; (6) the quality of I/M
repairs is a problem, to some extent, in every program
audited. EPA believes that the resolution of these problems
generally rests with each State/local I/M program developing
an overall I/M quality assurance program to ensure that
problems are identified and resolved in a timely manner.

-40-


EMISSION FACTORS: MOBILE MODELS
(see also Air Quality)

MOBILE4 Exhaust Emission Factors and Inspection/Maintenance
Benefits for Passenger Cars, E.L. Glover, and DJ.
Brzezinski, EPA-AA-TSS-IM-89-3, Aug 1989.

The MOBILE4 Tech 1V Credit Model is used to estimate the
emission factor equations, the effects of inspection and
Maintenance (I/M) programs, and the bag fraction equations
for 1981 and later passenger cars. The model's results are
then stored in the EPA MOBILE4 emission factor model
database. The report describes the development, use and
results of the Tech 1V_ model. It also documents the
normalized bag fractions, high altitude emission factors,
biennial I/M credits, and idle emission I/M credits used in
MOBILE4.

MOBILE4 Oxygenated Fuels Version User's Guide, E.L. Glover,
EPA-AA-TSS-IM-89-1, Aug 1989.

The document briefly describes changes made to the standard
MOBILE4 emission factors program to create a special version
which facilities modeling the effect of the use of oxygenated
fuel on carbon monoxide (CO) emissions from mobile sources.
The document also explains the changes made to the MOBILE4
input and output formats to allow user input of oxygenated
fuel use. Finally, examples of input and output files for
the model are provided.

Guidance on Estimating Motor Vehicle Emission Reductions from
the Use of Alternative Fuels and Fuel Blends. Emission

Control Technology Div., EPA-AA-TSS-PA-87-4, Jan 1988.

The document provides methods and assumptions for estimating
the impact of use of alternative fuels and fuel blends on
motor vehicle emissions including HC, CO, and NOx. The
information is presented in a format which assumes it will be
used by State and local air quality planning agencies in
preparing current and future emissions inventories and
emission reduction strategies during 1988, 1989, and 1990.
Such planning efforts will be necessary in areas which
receive calls from EPA for revisions to their ozone or CO
State implementation Plans (SIP) following their failure to
attain (or in a few cases following their failure to attain
(or in a few cases following their failure to provide for
attainment in a prospective sense) the National Ambient Air

-26-


diagnostic check was performed for each configuration after
the initial baselines. This report presents the measured
data taken during the tests. :

Evaluation of the Applicability of Inspection/Maintenance

Tests on a 1981 Cadillac Seville With Throttle Body Fuel
Injection, B. Smuda, EPA-AA-IMS-81-12, PB 81 203 341,

April 1981.

This report presents test results which were gathered to
determine the suitability of existing I/M short tests on a
Cadillac car with a computer based emission control system.
This car had a microprocessor-based engine control system
with throttle body fuel injection (TBI), modulated displace-
ment and a dual bed catalyst. After suitable baselines were
established, various components were made inoperative in the
emission control system. Complete FTP, HFET, and I/M tests
were run for each vehicle condition. Also, an on-board
system diagnostic check was performed for each configur-
ation. This report presents the measured data taken during
the tests.

Derivation of I/M Benefits for Post-1980 Light Duty Vehicles

for Low Altitude, Non-California Areas, D. Hughes, EPA-AA-
IMS-81-2, PB 81 194 102, January 1981.

This report discusses the derivation of I/M benefits for the
post-1980 Federal fleet as contained in EPA's emission factor
model MOBILE2. As is widely recognized, the post-1980 model
year fleet will be predominantly composed of vehicles which
employ what has become known as three-way catalyst technol-
ogy. This technology incorporates a sophisticated
microprocessor—based engine control system which holds the
air/fuel ratio very close to stoichiometry, thereby allowing
the three-way catalyst to simultaneously convert hydrocarbons
(HC), carbon monoxide (CO), and oxides of nitrogen (NOx) to
harmless by-products. Such a significant shift in technology
will have an impact on the expected in-use emissions
performance of these vehicles both with and without an
inspection and maintenance (I/M) program.

Evaluation of the Applicability of Inspection/Maintenance

Tests on a Toyota Celica Supra, B. Smuda, EPA-AA-IMS-80-9,
PB 81 194 094, December 1980.

This report presents test results which were gathered to
determine the suitability of existing I/M short tests on a
Toyota car with a computer based emission control system.
This car had a microprocessor based fuel injection system and
a small light-off catalyst followed by a three-way catalyst.

-10-


FUEL - ECONOMY

Costs, Benefits, and Methods of Including Tire Inflation in

State Vehicle Inspection Programs, Booz, Allen & Hamilton,
EPA-460-3-81-022, PB 82 131 137, September 1981.

This report presents information to help states include a
tire inflation, check in their existing and planned motor
vehicle safety or emissions inspection programs. It has been
estimated that as much as 515 million gallons of gasoline are
wasted in the U.S. each year due to improper tire inflation.
Tire inflation, if added to an inspection program would help
motorists increase vehicle fuel economy, reduce tire wear,
and improve safety. States adding tire inflation to
inspection programs would thereby increase the
cost-effectiveness of their programs. This report explores
the options available in implementing a tire inflation
check. It estimates fuel economy benefits and dollar savings
from various scenarios. Dollar savings from reduced tire
wear and fuel savings are estimated for vehicle owners. It
estimates the cost of adding the tire inflation check to an
inspection program. A step-by-step methodology is provided
to aid program planners in determining the potential cost
impact of the program and the fuel economy and treadware
benefits of the program.

Update on the Fuel Economy Benefits of Inspection and

Maintenance Programs, R. Michael, EPA-AA-IMS-81-10,
PB 81 203 333, April 1981.

The average annual fuel savings per inspected vehicle in the
basic I/M program is 0.3% or an annual savings of $3. With
optional elements added to the basic program (a more
effective test - either a Two Speed Idle Test or the Loaded
Test - for 1981 and later vehicles, a mechanics training
program, and a tire pressure check), annual fuel savings
would increase to as much as $23 per inspected vehicle per
year, a 2.5% fuel savings. The savings from the optional
program can completely offset the costs of I/M. The
nationwide annual fuel savings from I/M would be 83.6 million
gallons in the basic program and 701.4 million gallons in
the optimum program.

-13-