United States Air and Radiation EPA420-R-00-007
Environmental Protection April 2000
Agency
vxEPA IM240 & Evap
Technical
> Printed on Recycled Paper
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EPA420-R-00-007
April 2000
&
Transportation and Regional Programs Division
Office of Transportation and Air Quality
U.S. Environmental Protection Agency
NOTICE
This technical report does not necessarily represent final EPA decisions or positions.
It is intended to present technical, analysis of issues using data, which are currently available.
The purpose in the release of such reports is to facilitate the exchange of
technical information and to inform the public of technical developments which
may form the basis for a final EPA decision, position, or regulatory action.
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Introduction
§85.2205 Test Standards 1
(a) IM240 Emission Standards 1
(b) Transient Test Score Calculations 5
(c) Evaporative System Pressure Test Standards 10
(d) Gas Cap Test Standards 10
§85.2221 IM240 Test Procedures 12
(a) General Requirements 12
(b) Pre-inspection and Preparation 12
(c) Equipment Positioning and Settings 13
(d) Vehicle Conditioning 14
(e) Vehicle Emission Test Sequence 15
(f) Emission Measurements 18
§85.2222 Evaporative System Pressure and Gas Cap Test Procedures 19
(a) General Requirements 19
(b) Pre-inspection and Preparation 19
(c) Fuel Inlet Pressure Test 19
(d) Gas Cap Test 20
§85.2226 IM240 Equipment Specifications 21
(a) Dynamometer Specifications 21
(b) Constant Volume Sampler 25
(c) Analytical Instruments 27
§85.2227 Evaporative System Equipment Specifications 29
(a) General Requirements 29
(b) Evaporative System Pressure Test Equipment 29
(c) Gas Cap Test Equipment 29
§85.2234 IM240 Test Quality Control Requirements 31
(a) General Requirements 31
(b) Dynamometer 31
(c) Constant Volume Sampler 33
(d) Analysis System 34
(e) Gases 36
(f) Overall System Performance 37
(g) Control Charts 37
§85.2235 Evaporative Test Quality Control Requirements 39
(a) General Requirements 39
(b) Evaporative Pressure Checks 39
(c) Evaporative Gas Cap Checks 39
§85.2239 Test Report 40
(a) General Test Report Information 40
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(b) Tests and Results 40
(c) Recommended IM240 Second-By-Second Emissions Report 41
§85.2241 Terms 43
Appendix A
Guidance on the Use of Fast-Pass IM240 Standards 44
Appendix B
Alternative Fast-Pass IM240 Standards 50
Appendix C
Fast Pass IM240 Standards Developed for Wisconsin 66
Appendix D
Fast Pass IM240 Standards: Modal Regression Technique 73
Appendix E
Calculation of Raw Emission Scores from Dilute Measurements 82
Appendix F
Modal Analysis of Second-by-Second Data Preconditioning Guidelines 87
Appendix G
Full and Fast-Pass IM240 Positive Kinetic Energy Speed Variation Limits 91
Appendix H
Derivation of TRLHP Coefficients 100
Appendix I
Derivation of TRLHP Coefficients 103
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Introduction
This document is the successor to the August 1998 version of the EPA "IM240 & Evap Technical Guidance" and
incorporates changes made since its publication. The following changes have been incorporated in this release of
the EPA I/M technical guidance:
1) All references to the EPA evaporative emission purge test have been removed. Standards, procedures,
specifications, and quality control practices are described in the August 1998 technical guidance.
2) A spreadsheet and example for usage of the Modal Fast Pass concept have been posted with the IM240 & Evap
Technical Guidance on the EPA I/M web site..
3) Kl and K2 coefficients have been changed in 85.2205(b)(3)(iv)(E) to make them technically correct.
4) The exponent in the humidity correction factor in 85.2205(b)(3)(xi)(F) has been corrected for a typographical
error.
5) References to procedures for treatment of OBD II evaporative emission controlled vehicles have been revised to
state that guidance for these vehicles will be published in a separate document, not a revision of the IM240 & Evap
Technical Guidance.
6) The standard for the fuel inlet pressure test, 85.2205(d)(2)(i) has corrected a typographical error. The value "8"
has been changed to "6."
7) 85.2222(a)(2) has added a sentence stating fuel volatility is also a factor contributing to test variability when
conducting the fuel inlet pressure test.
8) 85.2226(a)(3)(iii) has been revised to specify response time measurements at 2000, base inertia, and 5500
pounds of inertia.
9) 85.2227(b)(l)(i) has been added to specifically permit the use of flow based leak detection methods, but no
standards have been proposed at present.
10) The text in 85.2227(c)(l)(iv) has been revised to clarify the term "automated." The new wording states
automatic operation means automated measurement of the pass/fail condition and a requirement for a real time data
link.
11) Paragraphs (ii) and (iii) of 85.2234 have been modified to provide more flexible load settings at 50 and 20 mph
to achieve longer and more measurable coast down times. The 22 to 18 mph coastdown limit has been changed to
± 6 seconds.
12) The 0.4% of point tolerance in 85.2234(d)(3) has been revised to ± 2% of point of a specific analyzer range,
and the first sentence is modified to state its intent is to apply to the initial setting of a span point.
13) Paragraph 4 of 85.2234(g)(4) has been revised to state that driving trace quality is an example of how control
charts for individual inspectors may used.
14) An equation has been added to 85.2239(b)(6) to define how "gpme" is calculated.
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15) Appendix I, Derivation of CTRL Coefficients has been revised to clarify its content, and make it more
compatible with terms and equations provided by Sierra Research in the supporting documentation when the EPA
I/M Look-up Table is revised.
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§85.2205 Test Standards
(a) IM240 Emission Standards
(1) Two Ways to Pass Standards. If the corrected, composite emission rates calculated in
§85.2205(b) exceed the standards for any exhaust component, additional analysis of test results
shall look at the second phase of the driving cycle separately. Phase 2 shall include second 94
through second 239. Second-by-second emission rates in grams, and composite emission rates
in grams per mile for Phase 2 and for the entire test shall be recorded for each gas. If the
composite emission level is equal to or below the composite standard, or if the Phase 2 grams
per mile emission level is equal to or below the applicable Phase 2 standard, then the vehicle
shall pass the test for that exhaust component.
(2) Start-up Standards. Start-up standards should be used during the first two years of program
operation. Tier 1 standards are recommended for 1996 and newer vehicles and may be used for
1994 and newer vehicles certified to Tier 1 standards as well. The following exhaust emissions
standards, in grams per mile, are recommended:
(i)
Light Duty Vehicles.
Model Years
Hydrocarbons
Carbon Monoxide
1996+
1991-1995
1983-1990
1981-1982
1980
1977-1979
1975-1976
1973-1974
1968-1972
Composite Phase 2
0.80 0.50
1.20 0.75
2.00 1.25
2.00 1.25
2.00 1.25
7.50 5.00
7.50 5.00
10.0 6.00
10.0 6.00
Composite Phase 2
15.0 12.0
20.0 16.0
30.0 24.0
60.0 48.0
60.0 48.0
90.0 72.0
90.0 72.0
150 120
150 120
(n) High- Altitude Light Duty Vehicles.
Model Years
1983-1984
1982
(iii) Light
Model Years
1996+
(<3750 LVW)
(>3750 LVW)
1991-1995
1988-1990
1984-1987
1979-1983
Hydrocarbons
Composite Phase 2
2.00 1.25
2.00 1.25
Duty Trucks (0 - 6000 pounds
Hydrocarbons
Composite Phase 2
0.80 0.50
1.00 0.63
2.40 1.50
3.20 2.00
3.20 2.00
7.50 5.00
Carbon Monoxide
Composite Phase 2
60.0 48.0
75.0 60.0
GVWPO.
Carbon Monoxide
Composite Phase 2
15.0 12.0
20.0 16.0
60.0 48.0
80.0 64.0
80.0 64.0
100 80.0
Oxides of Nitrogen
Composite Phase 2
2.0
2.5
3.0
3.0
6.0
6.0
9.0
9.0
10.0
2.0
2.5
3.0
3.0
6.0
6.0
9.0
9.0
10.0
Oxides of Nitrogen
Composite Phase 2
3.0
3.0
3.0
3.0
Oxides of Nitrogen
Composite Phase 2
2.0
2.5
3.0
3.5
7.0
7.0
2.0
2.5
3.0
3.5
7.0
7.0
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1975-1978
1973-1974
1968-1972
8.00 5.00
10.0 6.00
10.0 6.00
Civ) High-Altitude Light Duty Trucks
Model Years
1991+
1988-1990
1984-1987
1982-1983
Hydrocarbons
Composite Phase 2
3.00 2.00
4.00 2.50
4.00 2.50
8.00 5.00
120 96.0
150 120
150 120
(0 - 6000 Bounds GVWR1
Carbon Monoxide
Composite Phase 2
70.0 56.0
90.0 72.0
90.0 72.0
130 104
9.0 9.0
9.0 9.0
10.0 10.0
Oxides of Nitrogen
Composite Phase 2
3.0 3.0
3.5 3.5
7.0 7.0
7.0 7.0
(v) Light Duty Trucks (600 1 - 8500 pounds GVWPO.
Model Years
1996+
(<5750 ALVW)
(>5750 ALVW)
1991-1995
1988-1990
1984-1987
1979-1983
1975-1978
1973-1974
1968-1972
Hydrocarbons
Composite Phase 2
1.00 0.63
2.40 1.50
2.40 1.50
3.20 2.00
3.20 2.00
7.50 5.00
8.00 5.00
10.0 6.00
10.0 6.00
(vi) High-Altitude Light Duty Trucks
Model Years
1991+
1988-1990
1984-1987
1982-1983
Hydrocarbons
Composite Phase 2
3.00 2.00
4.00 2.50
4.00 2.50
8.00 5.00
(vii) Heaw-Dutv Trucks (greater than
Model Years
1998+
1991-1997
1987-1990
Hydrocarbons
Composite Phase 2
2.00 1.30
3.00 1.90
3.00 1.90
Carbon Monoxide
Composite Phase 2
20.0 16.0
60.0 48.0
60.0 48.0
80.0 64.0
80.0 64.0
100 80.0
120 96.0
150 120
150 120
(6001 - 8500 pounds GVWRY
Carbon Monoxide
Composite Phase 2
70.0 56.0
90.0 72.0
90.0 72.0
130 104
8500 Bounds GVWPO.1
Carbon Monoxide
Composite Phase 2
30.0 24.0
60.0 48.0
60.0 48.0
Oxides of Nitrogen
CompositePhase 2
2.5 2.5
4.0 4.0
4.5 4.5
5.0 5.0
7.0 7.0
7.0 7.0
9.0 9.0
9.0 9.0
10.0 10.0
Oxides of Nitrogen
Composite Phase 2
4.5 4.5
5.0 5.0
7.0 7.0
7.0 7.0
Oxides of Nitrogen
Composite Phase 2
4.0 4.0
6.0 6.0
8.0 8.0
The heavy-duty truck standards provided here were calculated using new vehicle certification standards and
have not been subjected to field testing. This document provides no other guidance on heavy duty truck testing.
Thus, anyone interested in performing IM240 tests on heavy-duty trucks should proceed with appropriate caution.
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1985-1986
1979-1984
1974-1978
1970-1973
pre-1970
5.00
6.00
10.0
10.0
20.0
3.10
3.80
6.30
6.30
12.50
75.0
100.0
150.0
175.0
200.0
60.0
80.0
120.0
140.0
160.0
8.0
8.0
10.0
10.0
15.0
8.0
8.0
10.0
10.0
15.0
(3) Final Standards. The following exhaust emissions standards, in grams per mile, are
recommended for vehicles tested in the calendar years 1997 and later. Tier 1 standards are
recommended for all 1996 and newer vehicles but may be used for 1994 and newer vehicles.
(i)
Light Duty Vehicles.
Model Years
Hydrocarbons
Carbon Monoxide
1996+
1983-1995
1981-1982
1980
1977-1979
1975-1976
1973-1974
1968-1972
Composite Phase 2
0.60 0.40
0.80 0.50
0.80 0.50
0.80 0.50
3.00 2.00
3.00 2.00
7.00 4.50
7.00 4.50
Composite Phase 2
10.0 8.0
15.0 12.0
30.0 24.0
30.0 24.0
65.0 52.0
65.0 52.0
120 96.0
120 96.0
(ii) High- Altitude Light Duty Vehicles.
Model Years
1983-1984
1982
Hydrocarbons
Composite Phase 2
1.20 0.75
1.20 0.75
(iii) Light Duty Trucks (0 - 6000 pounds
Model Years
1996+
(<3750 LVW)
(>3750 LVW)
1988-1995
1984-1987
1979-1983
1975-1978
1973-1974
1968-1972
Hydrocarbons
Composite Phase 2
0.60 0.40
0.80 0.50
1.60 1.00
1.60 1.00
3.40 2.00
4.00 2.50
7.00 4.50
7.00 4.50
(iv) High- Altitude Light Duty Trucks (0
Model Years
1988+
1984-1987
Hydrocarbons
Composite Phase 2
2.00 1.25
2.00 1.25
Carbon Monoxide
Composite Phase 2
30.0 24.0
45.0 36.0
GVWPO.
Carbon Monoxide
Composite Phase 2
10.0 8.0
13.0 10.0
40.0 32.0
40.0 32.0
70.0 56.0
80.0 64.0
120 96.0
120 96.0
- 6000 pounds GVWPO.
Carbon Monoxide
Composite Phase 2
60.0 48.0
60.0 48.0
Oxides of Nitrogen
Composite Phase 2
1.5
2.0
2.0
4.0
4.0
6.0
6.0
7.0
1.5
2.0
2.0
4.0
4.0
6.0
6.0
7.0
Oxides of Nitrogen
Composite Phase 2
2.0
2.0
2.0
2.0
Oxides of Nitrogen
Composite Phase 2
1.5
1.8
2.5
4.5
4.5
6.0
6.0
7.0
1.5
1.8
2.5
4.5
4.5
6.0
6.0
7.0
Oxides of Nitrogen
Composite Phase 2
2.5
4.5
2.5
4.5
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1982-1983
4.00
2.50
90.0
72.0
4.5
4.5
(V)
Light Duty Trucks (6001 - 8500 pounds GVWPQ.
Model Years
Hydrocarbons
Carbon Monoxide
Oxides of Nitrogen
1996+
(<5750 ALVW)
(>5750 ALVW)
1988-1995
1984-1987
1979-1983
1975-1978
1973-1974
1968-1972
Composite
0.80
0.80
1.60
1.60
3.40
4.00
7.00
7.00
Phase 2
0.50
0.50
1.00
1.00
2.00
2.50
4.50
4.50
Composite
13.0
15.0
40.0
40.0
70.0
80.0
120
120
Phase 2
10.0
12.0
32.0
32.0
56.0
64.0
96.0
96.0
Composite
1.8
2.0
3.5
4.5
4.5
6.0
6.0
7.0
Phase 2
1.8
2.0
3.5
4.5
4.5
6.0
6.0
7.0
(vi)
High-Altitude Light Duty Trucks (6001 - 8500 pounds GVWRX
Model Years
1988+
1984-1987
1982-1983
Hydrocarbons
Composite Phase 2
Carbon Monoxide
Composite Phase 2
Oxides of Nitrogen
Composite Phase 2
2.00
2.00
4.00
1.25
1.25
2.50
60.0
60.0
90.0
48.0
48.0
72.0
3.5
4.5
4.5
3.5
4.5
4.5
(vii) Heaw-Dutv Trucks (greater than 8500 pounds GVWPQ.
Model Years
Hydrocarbons
Composite Phase 2
Carbon Monoxide
Composite Phase 2
Oxides of Nitrogen
Composite Phase 2
1998+
1991-1997
1987-1990
1985-1986
1979-1984
1974-1978
1970-1973
pre-1970
2.00
2.00
2.00
3.00
5.00
10.0
10.0
20.0
1.30
1.30
1.30
1.90
3.10
6.30
6.30
12.50
30.0
40.0
40.0
50.0
75.0
150.0
175.0
200.0
24.0
32.0
32.0
40.0
60.0
120.0
140.0
160.0
4.0
5.0
6.0
6.0
6.0
10.0
10.0
15.0
4.0
5.0
6.0
6.0
6.0
10.0
10.0
15.0
(4) Fast-Pass. Vehicles may be fast-passed using the following algorithm.
(i) Fast-Pass Algorithm. Beginning at second 30 of the driving cycle, cumulative second-
by-second emission levels for each second, calculated from the start of the cycle in
grams, shall be compared to the cumulative fast-pass emission standards for the second
under consideration. For exhaust components subject to Phase 2 standards, cumulative
second-by-second emission levels calculated in grams from second 109 forward shall
be compared to cumulative second-by-second fast-pass Phase 2 emission standards for
the second under consideration.
(ii) Fast-Pass Standards. A vehicle shall pass the IM240 for a given exhaust component if
either of the following conditions occur:
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(A) cumulative emissions of each exhaust are below the full cycle fast-pass
standard for the second under consideration; or,
(B) at second 109 and later, (if the exhaust component is subject to Phase 2
standards) cumulative Phase 2 emissions of each exhaust component
are below the Phase 2 fast-pass standards for the second under
consideration;
(iii) Fast-Pass End of Test. Testing may be terminated when fast-pass criteria are met for
all subject exhaust components.
(iv) Applicability of Fast-Pass Standards. If a fast-pass determination cannot be made for
all subject exhaust components before the driving cycle ends, the pass/fail
determination for each component shall be based on composite or Phase 2 emissions
over the full driving cycle as described in §85.2205(a)(l).
(v) Fast-Pass Algorithms. Vehicles may be fast-passed using other approaches if they are
approved by the Administrator. States are encouraged to develop and use equations to
define fast-pass standards for each composite emission standard rather than using
tabular standards for each second of the test.
EPA-developed, tabular, fast-passed standards are included in Appendix A.
Fast-pass standards developed by Radian for Colorado are included in Appendix B.
Appendix C contains fast-pass standards generated by EPA for Wisconsin at the state's
request. This was done to allow the state to move toward implementing final IM240
standards.
Appendix D contains fast-pass guidelines and 0.8 g/mi HC composite standards along
with 0.5 g/mi HC Phase 2 cut points developed by Sierra Research under contract 68-
C4-0056 Work Assignment 2-04. A complete listing of the modal regression
coefficients would be too large to print in an appendix; however, the description in
Appendix D is intended to provide background information and the rational behind this
methodology. A complete series of coefficients are available on EPA's web site.
(b) Transient Test Score Calculations
(1) Composite Scores. The composite scores for the test shall be determined by dividing the sum of
the mass of each exhaust component obtained in each second of the test by the number of miles
driven in the test. The first data point is the sample taken from t=0 to t=l. The composite test
value shall be calculated by the equation in §85.2205(b)(l)(i):
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(i) Composite gpm = s °
/ <«—,
distance(miles)
s=0
Where: s = duration of test in seconds for fast pass
239 seconds for complete IM240
(2) Second-bv-Second Mass Calculations. The mass of each exhaust component shall be calculated
to five significant digits for each second of the test using the following equations:
HC
(i) Hydrocarbon mass:
1,000,000
^""^ conc
(ii) Carbon Monoxide mass: CO™.,™ = Vm™ * Densitypo *
mass mix ^CO j 0QO,000
NOCO
(iii) Oxides of Nitrogen mass: NOxmass ~ vmix * DensityNO2 * KH *
1,000,000
C02
^ ^ CO
(iv) Carbon Dioxide mass: CO2mass = vmix * DensitycO2 * ~
(3) Meaning of Terms.
© Vmix = The CVS flow rate in cubic feet per second corrected to standard
temperature and pressure.
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(ii) HCjnasg = Hydrocarbon emissions in grams per second.
(iii) Densityjjc = Density of hydrocarbons is 16.33 grams per cubic foot assuming an
average carbon to hydrogen ratio of 1:1.85 at 68°F and 760 mm Hg
pressure.
(iv) HCconc = Average hydrocarbon concentration per second of the dilute exhaust
sample corrected for background, in ppm carbon equivalent, i.e.,
equivalent propane * 3.
(A) HCconc = HCe-HCd(l ) Where:
DF
(B) HCe = Hydrocarbon concentration of the dilute exhaust sample, in
ppm carbon equivalent.
(C) HCfj = Background hydrocarbon concentration of the dilution air, in
ppm carbon equivalent.
,D, DF -
C02e+(HCe +C0e)*10
~4
This is calculated on a second-by-second basis, where CC>2 is measured in
% and HC and CO are measured in ppm. Note this DF does not account
for pollutants in the background air and becomes less accurate as the air-
fuel ratio of the vehicle deviates from stoichiometric.
100-Ki(CO2d)-K2(COd)-K3(HCd)
(E) alt ~ Kl(CO2e-CO2d) + K2(COe-COd) + K3(HCe-HCd)
This method of calculating DF is also done on a second-by-second basis and
accounts for pollutants in the background air as well as being more accurate
than the method in (D) above when the vehicle deviates from stoichiometric
operation. All concentrations are expressed in volume percent and the values of
the constants for gasoline fuel are: Kl = 7.4806, K2 = 5.5936, and K3 =
57.0945. Appendix E contains additional information on this subject.
If raw emission scores are being determined from dilute measurements, EPA
recommends the use of this method for calculating DF.
(v) COjnasg = Carbon monoxide emissions in grams per second.
(vi) Density CQ = Density of carbon monoxide is 32.97 grams per cubic foot at 68°F and
760 mm Hg pressure.
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(vii) COconc = Average carbon monoxide concentration per second of the dilute
exhaust sample, corrected for background, water vapor, and CC>2
extraction, in ppm.
(A) C0conc = C0e-C0d(l-—)
(B) COe = Carbon monoxide concentration of the dilute exhaust, in ppm.
(C) COd = Background carbon monoxide concentration of the dilution air, in
ppm.
(viii) NOxmass = Oxides of nitrogen emissions in grams per second.
(ix) DensityNQ2 = Density of oxides of nitrogen is 54.16 grams per cubic foot assuming
they are in the form of nitrogen dioxide at 68°F and 760 mm Hg
pressure.
(x) NOxconc = Average concentration of oxides of nitrogen per second of the dilute
exhaust sample, corrected for background in ppm.
(A) N0xconc = N0xe-N0xd(l-—)
(B) NOxe = Oxides of nitrogen concentration of the dilute exhaust sample,
in ppm.
(C) NOxd = Background oxides of nitrogen concentration of the dilution air,
in ppm.
(xi) KJJ = humidity correction factor
(A) Standard Method
1.0
1.0 - 0.0047 * (H-75.0)
(B) H = Absolute humidity in grains of water per pound of dry air.
43.478 * Ra * Pd
iT
(C) Ra = Relative humidity of the ambient air, percent.
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(D) P(j = Saturated vapor pressure, mm Hg at the ambient dry bulb
temperature.
(E) Pjj = Barometric pressure, mm Hg.
(F) Revised method2
v _ [0.004977(H-75)-. 004447(1-75)]
KH - e
(G) H = Absolute humidity in grains of water per pound of dry air.
(H) T = Temperature in °F.
NOTE: If the calculated KH using either method of calculation is greater than 2.19, the
value of KH shall be set at 2. 19.
(xiii) CO2mass = Carbon dioxide emissions in grams per second.
(xiv) Density CQ2 = Density of carbon dioxide is 5 1 . 8 1 grams per cubic foot at 68°F and
760 mm Hg.
(xv) CO2Conc = Average carbon dioxide concentration per second of the dilute exhaust
sample, corrected for background, in percent.
(A) C02conc = C02e - C02d (1 - — )
JJr
(B) CO2d = Background carbon dioxide concentration of the dilution air, in
percent.
(4) Negative Values. Negative gram per second readings shall be integrated as zero and recorded
as such. Negative values measured for ambient background concentrations (HC^, CO^, CC^,
and NOxcj) used in 85.2205(b)(3) shall be calculated as zero and recorded as such.
(5) Determination of Raw Exhaust Concentrations from IM240 Results. Although the IM240 is a
mass-based test, it is possible to estimate tailpipe concentrations from the dilute measurements
for those vehicles only required to undergo an idle test. One method for performing this
This revised method for calculating KH as a function of both T and H is based on work performed by Sierra
Research under contract 68-C4-0056, Work Assignment 2-04. If the calculated value of KH exceeds 2.19, the
value of KH shall be set to 2.19. This analysis used the same MY69, 5-vehicle sample employed for the original
KH factor study that resulted in the current CFR standard KH calculation method (listed in (xi)(A) above).
However, in many cases IM testing occurs outside the temperature limits set by the CFR for the standard method;
therefore, at this time EPA recommends using the revised method when testing above 86 °F.
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calculation can be found in SAE manuscript 980678. Additional clarification on this can be
found in Appendix E.
(c) Evaporative System Pressure Test Standards
The methods described below are applicable to pre OBD II evaporative emission controlled
vehicles. OBD II vehicles equipped with evaporative control monitors and certified to the
enhanced evaporative emission standards are being phased-in with the 1996 through 1998
model years. Those vehicles must be tested using either OBD II scan tools, by measuring
pressure loss through an evaporative emission "service port," or by following vehicle
manufacturer specific instruction to avoid damaging rigid vapor lines which are prevalent on
many vehicles equipped with enhanced evaporative emission control systems. Procedures for
using OBD II scan tools will be published in a separate document.
All I/M programs conducting a pressure test must perform a leak check on the gas cap and
provide a unique test result.
(1) Visual Check. The vehicle shall fail the evaporative system visual check if any part of the
system is missing, damaged, improperly connected, or disconnected as described in
§85.2222(b).
(2) Fuel Inlet Pressure Test.
(i) Pressure Test Method. A vehicle shall fail the pressure test if the fuel vapor control
system isolated between the fuel inlet and a clamp on the line between the fuel tank
and the canister, (located as close to the canister as possible) loses more than 6 inches
of water pressure over a period of 120 seconds starting from a stabilized pressure of
14±1 inch of water.
(ii) Fast-Pass. Fast-pass determinations for the pressure test may be made anytime during
the pressure decay between 20 and 120 seconds if the measured pressure exceeds:
0.33*P: + 1.33
Where: Pm = Measured pressure in inches of water
Pj = Initial pressure in inches of water
t = Time in seconds
(d) Gas Cap Test Standards
The methods described below are applicable to pre OBD II evaporative emission controlled
vehicles. OBD II vehicles equipped with evaporative control monitors and certified to the
enhanced evaporative emission standards are being phased-in with the 1996 through 1998
model years. Procedures for OBD vehicles will be published in a separate document.
10
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Pressure decay methods using a 1 liter head space are currently permitted under the June 1996
version of the IM240 technical guidance. As this method has been widely used in IM240
testing it will continue to be allowed. The pressure decay loss of 6 inches of WC from a
starting pressure of 28 in. WC referenced to 70F and 1 atm and assuming a 1 liter head space,
equates to a flow rate of about 80 cc/min.
(1) Visual Check. The vehicle shall fail the gas cap visual check if the cap is missing, obviously
defective, or the wrong style cap for the vehicle. An example of a wrong style includes a cam
lock cap installed on fill pipe which requires a threaded cap. States conducting cap testing
should work with OEM suppliers to develop a user friendly method of identifying wrong style
gas caps.
(2) Pressure Decay Test Standard. For pressure decay methods using a 1 liter head space and the
June 1996 IM240 technical guidance, the fuel cap shall fail the pressure test if it loses more
than 6 inches of water column (WC) pressure over a period of 10 seconds from a starting
pressure of 28±1 inch WC.
(3) 60 cc/min Flow Standard. The gas cap leak rate may be determined by pressure loss
measurement, direct flow measurement, or flow comparison methods and shall be compared to
a pass/fail flow rate standard of 60 cubic centimeters per minute of air at 30 inches of water
column. The flow rate methods shall be referenced to standard conditions of 70 °F and 1 atm.
If the leak rate exceeds 60 cc/min at a pressure of 30 inches of water column, the cap shall fail
the test.
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§85.2221 IM240 Test Procedures
(a) General Requirements
(1) Test Parameters. The following information shall be determined for the vehicle being tested
and used to automatically select the dynamometer inertia, power absorption settings, and
evaporative emission test parameters.
(i) Model Year
(ii) Manufacturer
(iii) Model name
(iv) Body style
(v) Number of cylinders
(vi) Engine displacement
Alternative computerized methods of selecting dynamometer test conditions, such as VTN de-
coding, may be used.
(2) Ambient Conditions. The ambient temperature, absolute humidity, and barometric pressure
shall be recorded continuously during the transient test, or as a single set of readings if taken
less than 4 minutes prior to the transient driving cycle.
(3) Restart. If shut off, the vehicle shall be restarted as soon as possible before the test and shall be
running at least 30 seconds prior to the transient driving cycle.
(b) Pre-inspection and Preparation
(1) Accessories. All accessories (air conditioning, heat, defogger, radio, automatic traction control
if switchable, etc.) shall be turned off by the inspector, if necessary.
(2) Traction Control and Four-Wheel Drive (4WDX Vehicles with traction control systems that
cannot be turned off shall not be tested on two wheel drive dynamometers. Vehicles with 4WD
that cannot be turned off shall only be tested on 4WD dynamometers. If the 4WD function can
be disabled, then 4WD vehicles may be tested on two wheel drive dynamometers.
(3) Leaks. The vehicle shall be inspected for exhaust leaks. Audio assessment while blocking
exhaust flow, or measurement of carbon dioxide or other gases, shall be acceptable. Vehicles
with leaking exhaust systems shall be rejected from testing.
(4) Operating Temperature. The vehicle temperature gauge, if equipped and operating, shall be
checked to assess temperature. If the temperature gauge indicates that the engine is well below
(less than 180°F) normal operating temperature, the vehicle shall not be fast-failed and shall get
a second-chance emission test if it fails the initial test for any criteria exhaust component.
Vehicles in overheated condition shall be rejected from testing.
(5) Tire Condition. Vehicles shall be rejected from testing if tire cords, bubbles, cuts, or other
damage are visible. Vehicles shall be rejected that have space-saver spare tires, or unreasonably
sized tires on the drive axle. Vehicle tires shall be visually checked for adequate pressure level.
Drive wheel tires that appear low shall be inflated to approximately 30 psi, or to tire side wall
12
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pressure, or manufacturer's recommendation. The tires of vehicles being tested for the purposes
of program evaluation under §51.353(c) shall have their tires inflated to tire side wall pressure.
(6) Ambient Background. Background concentrations of hydrocarbons, carbon monoxide, oxides
of nitrogen, and carbon dioxide (HC, CO, NOX, and CC>2, respectively) shall be sampled as
specified in §85.2226(b)(2)(iv) to determine background concentration of dilution air. The
sample shall be taken for a minimum of 15 seconds within 120 seconds of the start of the
transient driving cycle, using the same analyzers used to measure tailpipe emissions except as
provided in §85.2226(c)(4)(iv). Average readings over the 15 seconds for each gas shall be
recorded in the test record. Testing shall be prevented until the average ambient background
levels are less than 20 ppmC HC, 30 ppm CO, and 2 ppm NOX, or outside ambient air levels
(not influenced by station exhaust), whichever are greater.
Other methods that do not employ a fixed analysis time of 15 seconds may be used, if approved
by the Administrator.
(7) Sample System Purge. While a lane is in operation, the CVS shall continuously purge the CVS
hose between tests. The blower may be turned off if the CVS is not in operation, but the system
shall be purged for 2 minutes prior to the start of a test if the blower has been turned off. The
off time shall be computer monitored and recorded to a history file for quality assurance.
(c) Equipment Positioning and Settings
(1) Roll Rotation. The vehicle shall be maneuvered onto the dynamometer with the drive wheels
positioned on the dynamometer rolls. Prior to test initiation, the rolls shall be rotated until the
vehicle laterally stabilizes on the dynamometer. Drive wheel tires shall be dried if necessary to
prevent slippage during the initial acceleration.
(2) Cooling System. The use of a cooling system is optional when testing at temperatures below
50 °F. Furthermore, the hood may be opened at the state's discretion. If a cooling system is in
use, testing shall not begin until the cooling system is positioned and activated. The cooling
system shall be positioned to direct air to the vehicle cooling system, but shall not be directed at
the catalytic converter.
(3) Vehicle Restraint. Testing shall not begin until the vehicle is restrained. Any restraint system
shall meet the requirements of §85.2226(a)(5)(vii). The parking brake shall be set for front
wheel drive vehicles prior to the start of the test. The parking brake need not be set for vehicles
that release the parking brake automatically when the transmission is put in gear.
(4) Dynamometer Settings. Dynamometer power absorption and inertia weight settings shall be
automatically chosen from an EPA-supplied electronic look-up table which will be referenced
based upon the vehicle identification information obtained in 85.2221(a)(l). Vehicles not listed
shall be tested using default power absorption and inertia settings in the latest version of the
EPA I/M Look-up Table, as posted on EPA's web site: www.epa.gov/orcdizux/im.htm
(5) Exhaust Collection System. The exhaust collection system shall be positioned to insure
complete capture of the entire exhaust stream from the tailpipe during the transient driving
cycle. The system shall meet the requirements of §85.2226(b)(2).
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(d) Vehicle Conditioning
(1) Queuing Time. When the vehicle queue exceeds 20 minutes, a vehicle shall get a second-
chance emission test if it fails the initial test and all criteria exhaust components are at or below
1.5 times the standard. At the state's discretion, second-chance testing may be granted if
criteria exhaust components exceed any preset level above the standard.
(2) Program Evaluation. Vehicles being tested for the purpose of program evaluation under
§51.353(c) shall receive two full transient emission tests (i.e., a full 240 seconds each). Results
from both tests and the test order shall be separately recorded in the test record. Emission
scores and results provided to the motorist may be from either test.
(3) Discretionary Preconditioning.
(i) Any vehicle may be preconditioned by maneuvering the vehicle on to the dynamometer
and driving the 94 to 239 second segment of the transient cycle in 85.2221(e)(l). This
method has been demonstrated to adequately precondition the vast majority of vehicles
(SAE 962091).
Other preconditioning cycles may be developed and used if approved by the
Administrator.
(ii) Alternatively, modal analysis of the failing second-by-second test data may be
performed to identify vehicles that would benefit from additional pre-conditioning.
Appendix F provides retest criteria developed by Sierra Research under EPA contract
68-C4-0056 Work Assignment 2-04.
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(e) Vehicle Emission Test Sequence
(1) Transient Driving Cycle. The vehicle shall be driven over the following cycle:
Time
second
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
Speed
mph
0
0
0
0
0
3
5.9
8.6
11.5
14.3
16.9
17.3
18.1
20.7
21.7
22.4
22.5
22.1
21.5
20.9
20.4
19.8
17
14.9
14.9
15.2
15.5
16
17.1
19.1
21.1
22.7
22.9
22.7
22.6
21.3
19
17.1
15.8
15.8
17.7
19.8
21.6
Time
second
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
Speed
mph
25.7
26.1
26.7
27.5
28.6
29.3
29.8
30.1
30.4
30.7
30.7
30.5
30.4
30.3
30.4
30.8
30.4
29.9
29.5
29.8
30.3
30.7
30.9
31
30.9
30.4
29.8
29.9
30.2
30.7
31.2
31.8
32.2
32.4
32.2
31.7
28.6
25.1
21.6
18.1
14.6
11.1
7.6
Time
second
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
Speed
mph
0
0
3.3
6.6
9.9
13.2
16.5
19.8
22.2
24.3
25.8
26.4
25.7
25.1
24.7
25.2
25.4
27.2
26.5
24
22.7
19.4
17.7
17.2
18.1
18.6
20
20.7
21.7
22.4
22.5
22.1
21.5
20.9
20.4
19.8
17
17.1
15.8
15.8
17.7
19.8
21.6
Time
second
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
Speed
mph
24.6
24.6
25.1
25.6
25.7
25.4
24.9
25
25.4
26
26
25.7
26.1
26.7
27.3
30.5
33.5
36.2
37.3
39.3
40.5
42.1
43.5
45.1
46
46.8
47.5
47.5
47.3
47.2
47.2
47.4
47.9
48.5
49.1
49.5
50
50.6
51
51.5
52.2
53.2
54.1
Time
second
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
Speed
mph
54.6
54.8
55.1
55.5
55.7
56.1
56.3
56.6
56.7
56.7
56.3
56
55
53.4
51.6
51.8
52.1
52.5
53
53.5
54
54.9
55.4
55.6
56
56
55.8
55.2
54.5
53.6
52.5
51.5
50.5
48
44.5
41
37.5
34
30.5
27
23.5
20
16.5
15
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43 23.2
44 24.2
45 24.6
46 24.9
47 25
91 4.1
92 0.6
93 0
94 0
95 0
139 22.2
140 24.5
141 24.7
142 24.8
143 24.7
187 54.6
188 54.9
189 55
190 54.9
191 54.6
235 13
236 9.5
237 6
238 2.5
239 0
) Driving Trace. The inspector shall follow an electronic, visual depiction of the time
(3)
relationship of the transient driving cycle, or trace. The visual depiction of the trace shall be of
sufficient magnification and adequate detail to allow accurate tracking by the driver and shall
permit the driver to anticipate upcoming speed changes. The trace shall also clearly indicate
gear shifts as specified in §85.2221(e)(3).
Shift Schedule. For vehicles with manual transmissions, inspectors shall shift gears according
to the following shift schedule:
Shift Sequence
(gear)
1-2
2-3
De-clutch
1-2
2-3
3-2
2-3
3-4
4-5
5-6
De-clutch
Speed
(miles per hour)
15
25
15
15
25
17
25
40
45
50
15
Nominal Cycle Time
(seconds)
9.3
47.0
87.9
101.6
105.5
119.0
145.8
163.6
167.0
180.0
234.5
Gear shifts shall occur at the points in the driving cycle where the specified speeds are obtained.
For vehicles with fewer than six forward gears the same schedule shall be followed while
disregarding shifts above the highest gear.
(4) Speed Excursion Limits. Speed excursion limits shall apply as follows:
(i) Upper Limit. The upper limit is 2 mph higher than the highest point on the trace within
1 second of the given time.
(ii) Lower Limit. The lower limit is 2 mph lower than the lowest point on the trace within
1 second of the given time.
(iii) Speed Variations. Speed variations greater than the tolerances (such as may occur
during gear changes) are acceptable provided they occur for no more than 2 seconds on
any occasion.
(iv) Underpowered Vehicles. Speeds lower than those prescribed during accelerations are
acceptable provided the vehicle is operated at maximum available power during such
accelerations until the vehicle speed is within the excursion limits. If the vehicle is
underpowered and unable to adequately follow the trace, it may at the State's
discretion be rejected from testing or given an idle test.
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(v) Exceedances. Exceedances of the limits in §85.2221(5)(ii) through §85.2221(5)(iii)
shall automatically result in a void test. The station manager can override the
automatic void of a test if the manager determines that the conditions specified in
§85.2221(e)(4)(iv) occurred.
(5) Speed Variation Limits.
(i) Limits. Based on work performed under contract 68-C4-0056, Work Assignment 2-04
the following Positive Kinetic Energy limits were developed by Sierra Research.
These results are based on an analysis of 16,581 DVI240 tests conducted in AZ.
(ii) PKE =
where: PPt = V2t-V2(t-i) mi2/hr2 for Vt> V(t-i)
PPt = 0 forVt = V(t-i)
x = distance (mi)
(iii) PKE Limits. Full Test PKE Limits:
Upper Limit 3456 mi/hr2
Lower Limit 3082 mi/hr2
NOTE: The test cycle shall be invalid for a pass/fail determination if the PKE value is
below the lower limit for a passing vehicle or above the upper limit for a failing
vehicle. PKE values alone should not be used to make an early pass/fail
determination.
Test cycles with PKE values outside the lower and upper limits shall be valid for
preconditioning provided that all other requirements are met.
(iv) Second-bv-Second Limits. Second-by-Second PKE upper and lower limits are listed in
Appendix G.
(6) Distance Criteria. The actual distance traveled for the transient driving shall be measured. If
the absolute difference between the measured distance and the theoretical distance for the actual
test exceeds 0.05 miles, the test shall be void.
(7) Vehicle Stalls. Vehicle stalls during the test shall void the test and result in a new test. More
than 3 stalls shall result in rejecting the vehicle from testing.
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(8) Inertia Weight Selection. The inertia weight selected for the vehicle shall be verified as
specified in §85.2226(a)(l)(i). For systems employing electrical inertia simulation, an
algorithm identifying the actual inertia force applied during the transient driving cycle shall be
used to determine proper inertia simulation.
(9) CVS Operation. The CVS operation shall be verified for each test for a CFV-type CVS by
measuring either the absolute pressure difference across the venturi or measuring the blower
vacuum behind the venturi for minimum levels needed to maintain choke flow for the venturi
design. The operation of an SSV-type CVS shall be verified throughout the test by monitoring
the difference in pressure between upstream and throat pressure. The minimum values shall be
determined from system calibrations. Monitored pressure differences below the minimum
values shall void the test.
(f) Emission Measurements
(1) Exhaust Measurement. The emission analysis system shall sample and record dilute exhaust
HC, CO, CO2, and NOX during the transient driving cycle as described in §85.2226(c).
18
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§85.2222 Evaporative System Pressure and Gas Cap Test Procedures
(a) General Requirements
(1) Pressure Test. The on-vehicle pressure tests described in §85.2222(c) shall be performed after
any tailpipe emission test. Vehicles receiving a pressure test specified in §85.2222(c) should
also be given a gas cap leak test specified in §§85.2222(d).
(2) Controlling Test Variability. The pressure test shall be conducted in a manner that minimizes
changes in temperature, since pressure measurements are affected by changes in the vapor space
temperature. Volume compensation for the pressure test is not required, but the vapor space
volume will affect the pressure decay measurement. Excessive fuel vapor pressure, although
not controllable at the time of test, may affect the accuracy and repeatability of the result.
(3) Gas Cap Test Requirement. A gas cap test described in §85.2222(d) may be performed before
or after the tailpipe emission test.
(4) Alternative Techniques. Alternative gas cap or pressure test procedures may be used if they are
shown to be equivalent or better than those described below.
(b) Pre-inspection and Preparation
(1) Visual Inspection - Canister. The evaporative canister(s) shall be visually checked to the degree
practical. A missing or obviously damaged canister(s) shall fail the visual evaporative system
check.
(2) Visual Inspection - System. The evaporative system hoses shall be visually inspected for the
appearance of proper routing, connection, and condition, to the degree practical. If any
evaporative system hose is misrouted, disconnected, or damaged, the vehicle shall fail the visual
evaporative system check.
(3) Visual Inspection - Gas Cap. If the gas cap is missing, obviously defective, or the wrong style
cap for the vehicle, the vehicle shall fail the visual inspection.
(c) Fuel Inlet Pressure Test
(1) Equipment Set-up. The vapor vent line(s) from the gas tank to the canister(s) shall be clamped
off as close to the canister(s) as practical without damaging evaporative system hardware. Dual
fuel tanks shall be checked individually if the complete vapor control system can not be
accessed by pressurizing from the fill pipe interface of only one fuel tank. The proper adapter,
as specified in §85.2227(c)(2)(i) shall be selected.
(2) Starting Pressure. The gas tank shall be pressurized to 14±1 inch of WC, or a vehicle specific
pressure as identified in the I/M Look-up Table.
(3) Stability. Pressure stability shall be monitored for a period of 10 seconds prior to the start of
the pressure decay measurement. One definition of stability is a loss of no more than 5 inches
WC over a 10 second period when the initial pressure is 14±1 inch WC. If the loss of pressure
in 10 seconds exceeds this value, two more attempts shall be made to reach stability. Failure to
achieve stability likely indicates the presence of a large leak and therefore failure of the pressure
test. Alternate definitions of stability may be proposed by the State and approved by the
Administrator. Stability criteria for flow comparator or direct flow measurement methods do
not apply.
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(4) Volume Compensation. Pressure decay measurements are affected by the vapor volume in the
fuel tank. Volume-compensated pressure decay measurements are presently not required. By
design, flow comparator or flow measurement methods do not require volume corrections.
(5) Pressure Monitoring. Close the pressure source and measure the loss in pressure over a 120
second interval. Fast-pass determinations may be made using the equations in
§85.2205(d)(2)(ii).
(6) Clamp Removal. Remove the clamp on the vapor line and carefully relieve pressure and
remove the adapter used to supply pressure to the vapor space.
(d) Gas Cap Test
(1) Cap Installation. The fuel cap, or caps, shall be removed from the fuel inlet(s) and installed on
a portable or bench test rig -using the adapter appropriate for the gas cap as specified in
§85.2227(d)(l)(ii).
(2) Leak Measurement. The gas cap leak rate shall be measured and compared against a 60 cc/min
at 30 in. WC flow standard. Pressure decay measurement using instruments with a 1 liter head
space shall be made from an initial pressure of 28 in. WC and be compared against a loss of 6
in. WC in 10 seconds.
(3) Cap Replacement. The fuel cap(s) shall be replaced on the fuel inlet and tightened
appropriately.
20
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§85.2226 IM240 Equipment Specifications
(a) Dynamometer Specifications
(1) General Requirements.
(i) Capacity. The dynamometer structure (e.g., bearings, rollers, pit plates, etc.) shall
accommodate all light-duty vehicles and light-duty trucks up to 8500 pounds GVWR.
(ii) Test Parameters. Road load horsepower and inertia simulation shall be automatically
selected from the EPA I/M Look-up Table, or equivalent data base, based on the
vehicle parameters in the test record.
(iii) Alternative Designs. Alternative dynamometer specifications, designs, and error
checking methods may be used if the alternative provides proper dynamometer loading
over the IM240 driving cycle.
(iv) Units. Specifications in this section are generally expressed in units of horsepower.
System designs using equivalent units of force, English or SI, are permissible.
(v) Ambient Range. The dynamometer shall be designed to meet specifications at an
ambient temperature range of 35 to 110°F, and at absolute humidity values
representative of the IM240 testing location.
(2) Power Absorption.
(i) Power Absorber Design. The power absorber unit shall be an electric AC or DC
motor/absorber design. Eddy current designs may be approved if proven equivalent to
other designs in terms of inertia response time, total load, and emissions performance
over an IM240 driving cycle.
(ii) Range.
(A) Mechanical Inertia Dynamometers. Dynamometers using clutchable flywheels
shall have sufficient power absorber capacity to accommodate the TRLHP
values in the EPA I/M Look-up Table.
(B) Electric Inertia Dynamometers. Dynamometers using a combination of
mechanical base inertia and supplemental electrical inertia shall have sufficient
power absorber capacity to accommodate the sum of the TRLHP values in the
EPA I/M Look-up Table plus the power absorbed from accelerating a vehicle at
3.3 mph/sec at the equivalent test weight (ETW) specified in the I/M Look-up
Table.
(iii) Accuracy. The power absorber shall be adjustable across the required horsepower
range at 50 mph in 0.1 horsepower increments. The accuracy of the power absorber or
power exchange unit, for road load simulation only, shall be ±0.25 horsepower or ±3%
of point, whichever is greater.
(iv) Indicated Horsepower. At constant velocity, the power absorber shall load the vehicle
according the following equations:
IHP = TRLHP - PLHP - CTRL
Where: IHP is the dynamometer indicated, or set, horsepower.
21
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TRLHP is the track, or total, horsepower for a particular vehicle.
PLHP is the dynamometer parasitic loss horsepower.
CTRL is the generic tire/roll loss of a vehicle on the dynamometer.
TRLHP, PLHP, CTRL, and therefore IHP, are all expressed as three term polynomials of
the type:
HP = A*Obmph + B*Obmph2 + C*Obmph3
Where: HP represents individual expressions relating IHP, TRLHP, PLHP,
or CTRL as a function of velocity.
A, B, or C represent horsepower coefficients for the individual
expressions relating IHP, TRLHP, PLHP, or CTRL as a function of
velocity.
Obmph is the velocity in miles per hour.
Expressions for TRLHP, and CTRL are found in Appendices H and I.
(3) Inertia.
(i) Range. The dynamometer shall provide inertia simulation capability of 2000 to 5500
pounds for light duty vehicles and trucks less than or equal to 5500 pounds ETW.
Dynamometers used for testing light duty vehicles and trucks over 5500 ETW shall
have inertia simulation capability to set the inertia at the correct value as referenced in
the EPA I/M Look-up Table.
(ii) Mechanical Inertia Simulation. The dynamometer shall be equipped with clutchable
mechanical flywheels with inertia selectable to a 250 pound sensitivity. The tolerance
on the base inertia weight and the flywheels shall be within 1% of the specified test
weights. The test system shall be equipped with a method, independent from the
flywheel selection system, that identifies which flywheels are actually rotating during
the transient driving cycle.
(iii) Electric Inertia Simulation. Electric inertia simulation, or a combination of electric and
mechanical simulation may be used in lieu of mechanical flywheels, provided that the
performance of the electrically simulated inertia complies with the following
specifications.
(A) System Response. The torque response to a step change shall be at least 90% of
the command value within 200 milliseconds, and shall be within 2 percent of the
commanded torque by 300 milliseconds after the command is issued. Any
overshoot of the commanded torque value shall not exceed 25 percent of the
torque value. Response time measurements shall be performed at 2000, base
inertia, and 5500 pounds of inertia.
(B) Simulation Error. An inertia simulation error (ISE) shall be continuously
calculated any time the actual dynamometer speed is between 10 and 60 mph.
The average positive ISE over the driving cycle shall be calculated by the
equation in §85.2226(a)(3)(iii)(C), and shall not exceed 2 percent of the inertia
weight selected (IWS) for the vehicle under test.
22
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ISE =
Where: ISE = Inertia simulation error expressed in percent.
IWS = Total inertia desired, or selected, in pounds mass.
It = Total inertia being simulated by the dynamometer in
pounds mass.
32.2 '
Where: It = Total inertia being simulated by the dynamometer in pounds mass.
Im = Base mechanical inertia of the dynamometer in pounds mass.
32.2 = Gravitational constant, (ft)(lbm)/(lbf)(sec2).
V = Measured roll speed in feet/second.
Fm = Force measured by the load cell converted to force at the roll
surface in pounds.
Frj = Dynamometer road load expressed as a three term polynomial in
pounds force at the measured roll speed.
t = Time in seconds.
(4) Dynamometer Parasitic Loss
(i) Friction Curves. The dynamometer internal friction curves, typically bearing and
windage friction expressed as a function of velocity, shall be capable of being
automatically measured, stored, and accurately accounted for over the IM240 driving
cycle.
(ii) Friction Curve Definition. Parasitic loss friction shall be expressed in a tabular format
as a function of velocity, or as a polynomial of the type:
PLHP = Ap*Obmph + BpObmph2 + CpObmph3
Where: PLHP represents the dynamometer parasitic friction, expressed in
horsepower.
Ap, Bp, and Cp are coefficients relating a least squares fit of
dynamometer friction and velocity.
Obmph is dynamometer roll surface velocity in miles per hour.
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(5) Rolls.
(i) Size and Type. The dynamometer shall be equipped with twin rolls. The rolls shall be
coupled side to side. In addition, the front and rear rolls shall be coupled. The
dynamometer roll diameter shall be between 8.5 and 21.0 inches. The spacing between
the roll centers shall comply with the equation in §85.2226(a)(5)(iii). The
dynamometer rolls shall accommodate an inside track width of 30 inches and an
outside track width of at least 100 inches.
(ii) Roll Installation. Rolls shall be installed in the floor such that vehicles will be within
±5 degrees of horizontal.
(iii) Roll Spacing. The spacing between the roll centers shall comply with the following
equation to within +0.5 inches and -0.25 inches.
Roll Spacing = (24.375 +D) * Sin 31.5°
Where: Roll Spacing is the distance between the roll centerlines in inches.
D = Roll diameter in inches
(iv) Roll Surface. The surface finish and hardness shall be such that tire slippage is
minimized when testing vehicles using the inertia weight and horsepower settings
found in the EPA I/M Look-up Table while following the IM240 driving schedule, and
that tire wear and noise are minimized. Knurled roll surfaces are acceptable.
(v) Test Distance and Vehicle Speed. The total number of dynamometer roll revolutions
shall be used to calculate the distance traveled. Pulse counters may be used to
calculate the distance directly if there are at least 16 pulses per revolution. The
measurement of the actual roll distance for the composite and each phase of the
transient driving cycle shall be accurate to within ±0.01 mile. The measurement of the
roll speed shall be accurate to within ±0.1 mph over the IM240 driving schedule.
(vi) Vehicle Lift. A vehicle lift system located between the dynamometer rolls shall be
provided to facilitate drive axle positioning and vehicle egress from the dynamometer.
(vii) Vehicle Restraint System. The dynamometer shall include a system of safely
restraining the forward and side-to-side motion of front wheel drive vehicles, and the
forward motion of rear wheel drive vehicles during the IM240 driving schedule, while
allowing unobstructed ingress and egress from the dynamometer.
(6) Load Cell.
(i) Torque Measurement. The dynamometer shall have a torque measurement system
accurate to within ±2% of full scale.
(ii) Dead Weights. Dead weights used to calibrate a torque meter or load cell shall be
traceable to NIST and be accurate to within ±0.5%.
(iii) Dynamic Calibrations. Designs using an F = MA method for calibrating the load cell
are also acceptable.
(7) Driver's Aid.
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(i) Video Display. The dynamometer shall be equipped with a video display device able
to be easily positioned to accommodate all test vehicles while clearly visible to the
driver. The display shall have a method that allows the driver to accurately and
smoothly follow the desired driving cycle.
(ii) Remote Capabilities. The dynamometer shall have a means of allowing the driver to
start the test, perform an emergency stop, and perform other necessary and convenient
functions related to the test while inside the vehicle.
(8) Other.
(i) Augmented Braking. Augmented braking shall be used during vehicle decelerations
on the driving cycle. Augmented braking shall be actuated only when the negative
force applied by the vehicle at the roll surface is greater than 110 pounds. If the
augmented braking is not linked to driver braking, the driver shall be signaled to not
accelerate during this period.
(ii) Cooling Fan. The cooling fan capacity shall be 5400 ±300 SCFM, positioned within
12 inches of the intake to the vehicle's cooling system, and avoid unrepresentative
cooling of the engine and exhaust control system.
(9) All Wheel Drive Dynamometers.
(i) Design. The dynamometer shall meet the requirements for two wheel drive vehicles
and be capable of testing traction control and all wheel drive vehicles in a safe manner
without damaging the vehicle.
(ii) Wheelbase. The all wheel drive dynamometer shall be capable of testing vehicles
having a wheelbase between 84 and 125 inches, or as necessary to meet the wheelbase
values in the I/M Look-up Table. The system shall provide a locking mechanism to
secure the roll at the desired wheelbase.
(iii) Speed Synchronization. Front and rear wheels shall maintain speed synchronization
within ±0.1 mph.
(b) Constant Volume Sampler
(1) General Design Requirements.
(i) Venturi Type. A constant volume sampling (CVS) system of the critical flow venturi
(CFV) or the sub-sonic venturi (SSV) type shall be used to collect vehicle exhaust
samples. The CVS system and components shall generally conform to the
specifications in §86.109-90.
(ii) CVS Flow Size. The CVS system shall be sized in a manner that prevents
condensation in the dilute sample over the range of ambient conditions to be
encountered during testing. A 700 SCFM system is assumed to satisfy this
requirement. The range of ambient conditions may require the use of heated sample
lines. Should heated sample lines be used, the lines and components shall be heated to
a minimum of 120 °F and a maximum of 250 °F, which shall be monitored during the
driving cycle.
(iii) CVS Compressor. The CVS compressor flow capacity shall be sufficient to maintain
proper flow in the main CVS venturi with an adequate margin. For CFV CVSs the
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margin shall be sufficient to maintain choke flow. The capacity of the blower relative
to the CFV flow capacity shall not be so large as to create a limited surge margin.
(iv) Materials. All materials in contact with exhaust gas shall be unaffected by and shall
not affect the sample (i.e., the materials shall not react with the sample, and neither
shall they taint the sample as a result of out gassing). Acceptable materials include
stainless steel, Teflon®, silicon rubber, and Tedlar®.
(v) Alternative Designs. Alternative CVS specifications, materials, or designs may be
allowed upon a determination by the Administrator, that for the purpose of properly
conducting an approved short test, the evidence supporting such deviations will not
significantly affect the proper measurement of emissions.
(2) Sample System.
(i) Sample Probe. The sample probe within the CVS shall be designed such that a
continuous and adequate volume of sample is collected for analysis. The system shall
have a method for determining if the sample collection system has deteriorated or
malfunctioned such that an adequate sample is not being collected, or that the response
time has deteriorated such that the time correlation for each emission constituent is no
longer valid.
(ii) CVS Mixing Tee.
(A) Design and Effect. The mixing tee for diluting the vehicle exhaust with
ambient air shall be at the vehicle tailpipe exit as in §86.109-90(a)(2)(iv). The
dilution mixing tee shall be capable of collecting exhaust from all light-duty
vehicle and light-duty truck exhaust systems. The design used shall not cause
static pressure in the tailpipe to change such that the emission levels are
significantly affected. A change of ±1.0 inch of water or less, as measured at
the tailpipe, shall be acceptable.
(B) Locating Device. The mixing tee shall have a device for positively locating
the tee relative to the tailpipe with respect to distance from the tailpipe, and
with respect to positioning the exhaust stream from the tailpipe(s) in the
center of the mixing tee flow area. The locating device, or the size of the
entrance to the tee shall be such that if a vehicle moves laterally from one
extreme position on the dynamometer to the other extreme, that mixing tee
will collect all of the exhaust sample.
(iii) Dual Exhaust. For dual exhaust systems, the design used shall insure that each leg of
the sample collection system maintains equal flow. Equal flow will be assumed if the
design of the "Tee" intersection for the dual CVS hoses is a " Y" that minimizes the
flow loss from each leg of the "Y," if each leg of the dual exhaust collection system is
approximately equal in length (± 1 foot), and if the dilution area at the end of each leg
is approximately equal. In addition, the CVS flow capacity shall be such that the
entrance flow velocity for each leg of the dual exhaust system is sufficient to entrain
all of the vehicle's exhaust from each tailpipe.
(iv) Background Sample. The mixing tee shall be used to collect the background sample.
The position of the mixing tee for taking the background sample shall be within 12
lateral and 12 longitudinal feet of the position during the transient driving cycle, and
approximately 4 vertical feet from the floor.
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(v) Integrated Sample. A continuous dilute sample shall be provided for integration by the
analytical instruments in a manner similar to the method for collecting bag samples as
described in §86.109-90.
(c) Analytical Instruments
(1) General Requirements.
(i) Instrument Specifications. The emission analysis system shall automatically sample,
integrate, and record the specified emission values for HC, CO, CO2, and NOx.
Performance of the analytical instruments with respect to accuracy and precision, drift,
interferences, noise, etc. shall be similar to instruments used for testing under §86
Subparts B, D, and N. Analytical instruments shall perform in this manner in the full
range of operating conditions in the lane environment.
(ii) Alternative Designs. Alternative analytic equipment specifications, materials, designs,
or detection methods may be allowed upon a determination by the Administrator, that
for the purpose of properly conducting an approved short test, the evidence supporting
such deviations will not significantly affect the proper measurement of emissions.
(2) Detection Methods and Instrument Ranges
(i) Total Hydrocarbon Analysis. Total hydrocarbon analysis shall be determined by a
flame ionization detector. If a 700 SCFM CVS is used, the analyzer calibration curve
shall cover at least the range of 0 ppmC to 2,000 ppmC. Use of a different CVS flow
capacity shall require an adjustment to these ranges. Appropriate documentation
supporting any adjustment in ranges shall be available. The calibration curve must
comply with the quality control specifications in §85.2234(d) for calibration curve
generation.
(ii) Carbon Monoxide Analysis. CO analysis shall be determined using a non-dispersive
infrared analyzer. If a 700 SCFM CVS is used, CO analysis shall cover at least the
range of 0 ppm to 10,000 ppm (1%). In order to meet the calibration curve
requirements, two CO analyzers may be required - one from 0 to 1000 or 2000 ppm,
and one from 0 to 1% CO. Use of a different CVS flow capacity shall require an
adjustment to these ranges. Appropriate documentation supporting any adjustment in
ranges shall be available. The calibration curve requirements and the quality control
specifications in §85.2234(d) apply to both analyzers.
(iii) Carbon Dioxide Analysis. CO2 analysis shall be determined using an NDIR analyzer.
If a 700 SCFM CVS is used, CO2 analysis shall cover at least the range of 0 ppm to
40,000 ppm (4%). Use of a different CVS flow capacity shall require an adjustment to
these ranges. Appropriate documentation supporting any adjustment in ranges shall be
available. The calibration curve must comply with the quality control specifications in
§85.2234(d) for calibration curve generation.
(iv) Oxides of Nitrogen Analysis. NOx analysis shall be determined using
chemiluminescence. The NOx measurement shall be the sum of nitrogen oxide and
nitrogen dioxide. Alternatively, NOX measurements may be made by re-calibrating the
chemiluminescence analyzer in NO only mode, then running the analyzer in NO only
mode and multiplying the result by 1.03. This will eliminate the need for the converter
and flow balance checks in §85.2234(d)(5) and §85.2234(d)(6).
If a 700 SCFM CVS is used, the NOx analysis shall cover at least the range of 0 ppm
to 500 ppm. Use of a different CVS flow capacity shall require an adjustment to these
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ranges. Appropriate documentation supporting any adjustment in ranges shall be
available. The calibration curve must comply with the quality control specifications in
§85.2234(d) for calibration curve generation.
(3) System Response Requirements. Historically, continuously integrated emission analyzers have
been required to have a response time of 1.5 seconds or less to 90% of a step change, where a
step change was 60% of full scale or better. System response times between a step change at
the probe and reading 90% of the change shall be less than 10 seconds.
(4) Integration Requirements.
(i) Sampling Frequency. The analyzer voltage responses, CVS pressure(s), CVS
temperature(s), dynamometer speed, and dynamometer power shall be sampled at a
frequency of no less than 5 Hertz, and the voltage levels shall be averaged over 1
second intervals.
(ii) Time Alignment. The system shall properly time correlate each analyzer signal and the
CVS signals to the driving trace.
(iii) Engineering Units. The one-second average analyzer voltage levels shall be converted
to concentrations by the analyzer calibration curves. Corrected concentrations for each
gas shall be derived by subtracting the pre-test background concentrations from the
measured concentrations, according to the method in §85.2205(b). The corrected
concentrations shall be converted to grams, for each second, using the equations
specified in §85.2205(b) to combine the concentrations with the CVS flow over the
same interval. The grams of emissions per test phase shall be determined using the
equations in §85.2205(b).
(iv) Multiple Analyzers. When multiple analyzers are used for any constituent, the
integration system shall simultaneously integrate both analyzers. The integrated values
for the lowest analyzer in range shall be used for each second.
(v) Background Samples. For all constituents, the background concentration levels from
the lowest range shall be used, including the case where multiple analyzers may have
been used.
(5) Analytical System Design.
(i) Materials. All materials in contact with exhaust gas prior to and throughout the
measurement portion of the system shall be unaffected by and shall not affect the
sample (i.e., the materials shall not react with the sample, and neither shall they taint
the sample as a result of out gassing). Acceptable materials include stainless steel,
Teflon, silicon rubber, and Tedlar®-
(ii) System Filters. The sample system shall have an easily replaceable filter element to
prevent paniculate matter from reducing the reliability of the analytical system. The
filter element shall provide for reliable sealing after filter element changes. If the
sample line is heated, the filter system shall also be heated.
(iii) Availability of Intermediate Calculation Variables. Upon request prior to a test, all
intermediate calculation variables shall be available to be downloaded to electronic
files or hard copy. These variables shall include those that calculate the vehicle
emission test results, perform emission analyzer and dynamometer function checks,
and perform quality assurance and quality control measurements.
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§85.2227 Evaporative System Equipment Specifications
(a) General Requirements
(1) Equipment Design. Automated and computerized test systems shall be used for the evaporative
system tests wherever they are appropriate. Pass/fail decisions shall be made automatically.
The systems shall be tamper resistant and designed to avoid damage to the vehicle during
installation, testing, and removal.
(2) Alternative Systems. Alternative purge, pressure, or gas cap test equipment specifications or
designs may be proposed by a State if they are supported by data and approved in advance by
the Administrator.
(b) Evaporative System Pressure Test Equipment
(1) General Requirements.
(i) Alternative Designs. Flow measurement or flow comparator leak detection methods
are acceptable if supported by data and approved in advance by the Administrator.
Standards for flow based methods have not been established.
(ii) Pressurizing Gas. Nitrogen, or an equivalent non-toxic, non-greenhouse, inert gas,
shall be used for pressurizing the evaporative system. Air should only be used if the
pressurized vapor space is outside the combustible limits for the vehicle fuel type.
(iii) Automatic Operation. The process for filling the vapor space, monitoring compliance,
recording data, and making a pass/fail decision shall be automatic. After the
determination that the evaporative system has been filled to the specified pressure
level, and upon initiation of the test, the pressure level in the evaporative system shall
be recorded at a frequency of no less than 1 Hertz until the conclusion of the test.
(iv) Test Abort. The system shall be equipped with an abort system that positively shuts
off and relieves pressure. The abort system shall be capable of being activated quickly
and conveniently by the inspector should the need arise.
(v) Grounding. A fillpipe pressure test must be designed to prevent electrostatic discharge
that would pose a flammability risk during the test.
(2) Adapters and Clamps.
(i) Fuel Inlet Adapters. Adapters attached to the fuel fillpipe inlet shall be used to supply
pressurized gas into the fuel tank. Adapters shall be available for at least 95 percent of
the fuel inlets that are used on U.S. light duty vehicles and light duty trucks for the
model years covered by the program.
(ii) Hose Clamp. The hose clamp used for the fuel inlet pressure test shall be designed to
apply only enough pressure to close the flexible vent line between the fuel tank and
canister without damaging it. The nose of the clamp shall be smooth-surfaced or
otherwise designed to avoid damage to the vent line.
(3) Pressure Gauge. The device for measuring pressure shall have a minimum range of 0 to 28
inches of water and an accuracy of +0.3 inches of water, or 2% of point, whichever is greater.
(c) Gas Cap Test Equipment
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(1) General Requirements.
(i) Alternative Designs. Leak testers failing gas caps with a test standard below 60 cc/min
at 30 in. WC are permissible provided they do not falsely fail gas caps designed to
meet vehicle manufacturer OEM specifications, are repeatable and accurate in a
centralized I/M environment, and demonstrate quantifiable reductions in real world
mass emissions. OEM leak rates for individual manufacturers are proprietary.
Information submitted to EPA shows some vehicle manufacturers had maximum leak
rates up to 20 cc/min at 30 inches of WC.
(ii) Gas Cap Adapters. The gas cap tester shall accommodate at least 95 percent of the gas
caps that are used on U.S. light duty vehicles and trucks for the model years covered
by the gas cap test program.
(iii) Pressurizing Gas. Air, Nitrogen, or an equivalent non-toxic, non-greenhouse, inert gas,
shall be used for pressurizing the gas cap tester.
(iv) Automatic Operation. The process for making a pass/fail decision shall be automated.
The gas cap tester shall provide for automated pass/fail determination and automated
transfer of the pass/fail result to a host computer, i.e. a real-time data link.
(v) Over-Pressurization. The tester shall control the supply pressure of the gas used for
pressure decay, direct flow measurement, or flow comparison methods and prevent
over-pressurization.
(2) Gas Cap Tester. Gas cap testers employing internal reference orifices, or pressure measurement
devices, shall be traceable to NIST flow or pressure measurement standards.
(i) Range. The tester shall identify passing gas caps with a leak rate equal to or less than
60 cc/min of air at 30 inches of WC, and failing caps with leak rates more than 60
cc/min at 30 inches of WC at reference conditions of 70F and 1 atm.
(ii) Filter. A serviceable air filter shall be incorporated upstream of flow orifices.
(iii) Power Supply. Battery powered testers shall be equipped with an automatic shutoff
and a low-battery indicator.
(iv) Accuracy. Pressure decay, direct flow measurement, or flow comparison methods
shall be accurate to ±3 cc/min at the 60 cc/min flow standard.
(v) Reference Caps and Orifices. NIST traceable reference passing fuel caps or orifices of
nominal 52-56 cc/min, and NIST traceable reference failing fuel caps or orifices of
nominal 64-68 cc/min shall be supplied with the tester for daily verification tests.
(vi) Head Space. Pressure decay methods shall employ a head space sized to produce
correct results at the 60 cc/min at 30 in. WC standard.
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§85.2234 IM240 Test Quality Control Requirements
(a) General Requirements
(1) Manufacturers' Recommendations. Manufacturers'recommendations for equipment
installation, calibration, and maintenance, shall be followed.
(2) Statistical Process Control. SPC tracking methods shall be established for appropriate
equipment checks and custom diagnostic or verification tests.
(3) Modifications to Quality Control Requirements. Changes to the type or frequency of the quality
checks are permitted provided they are based on SPC analysis, or data from experimental
studies.
(b) Dynamometer
(1) Dynamometer Manufacturer Recommendations
(i) Minimum Requirements. The dynamometer manufacturer's requirements for periodic
diagnostic checks, calibration, scheduled maintenance, and recommended quality
control monitoring shall be followed.
(ii) Warm-up Requirements. The dynamometer manufacturer's procedure for insuring
proper warm-up over a 35 to 110°F temperature range shall be followed.
(2) Coast Down Testing
(i) Frequency. Dynamometers with electric and mechanical inertia simulation shall
receive a daily unloaded (vehicle off the dynamometer) coast down check over the
range of 60 to 10 mph. This daily check shall be run at alternating combinations of
inertia and road load settings. Dynamometers using only mechanical flywheels for
inertia simulation shall also receive additional weekly coast down checks to properly
characterize the friction at other combinations of flywheel weights. The number of
these coast downs shall be established based on the dynamometer design and quality
control monitoring.
(ii) Load Settings. Inertia and power absorber settings shall be representative of vehicle
test conditions, and shall result in nominal coast down times of 15-20 seconds when
time is measured between 55 and 45 mph, and 22-33 seconds when time is measured
between 22 and 18 mph. Inertia settings for clutchable flywheel dynamometers are
discretionary but should attempt to be above and below the base inertia of the
dynamometer and represent high and low inertia weight vehicles.
(iii) Quality Control Limits. Actual control limits for the coast down tests shall be
established by statistical process control practices. The 55 to 45 mph and 22 to 18 mph
coastdown times shall be within ±1 second, and ± 6 seconds, respectively, of the
theoretical coast down times. These ±1 and ±6 second limits are based on the 15-20
and 22-33 second coastdown times in the preceding paragraph. Theoretical coastdown
time is based on the following equation:
/0.5*ETW/ U/V2 v2^
\ /32.2) ^Vi ~ V^
550*HP
Where: t = The coastdown time in seconds
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ETW = The Equivalent Test Weight in pounds
Vj = The initial roll velocity in feet/second
Vp = The final roll velocity in feet/second
IHP = The dynamometer indicated horsepower
An alternative to the ±1 or ±6 second limits is to perform an unloaded coastdown from
60 to 10 mph and reduce the speed/time data to produce a polynomial relationship
between horsepower (or force) versus time. The measured horsepower curve shall be
within ±0.25 horsepower or ±3% of point, whichever is greatest.
Dynamometers which exceed specific SPC limits or the coast down limits presented
above, shall be removed from service until corrective action is taken to assure the
dynamometer is performing satisfactorily.
(3) Parasitic Loss Checks
(i) Frequency. Checks of the parasitic loss curve shall be conducted at a frequency
recommended by the dynamometer manufacturer, as required by inspection of quality
control data, or as necessary following service to the dynamometer.
(ii) Quality Control Limits. Parasitic loss measurements shall be measured between 10
and 60 mph. Identification of outlier data shall be established by examination of
quality control data.
Dynamometers which exceed dynamometer specific SPC limits for parasitic loss
checks shall be removed from service until corrective action is taken to ensure the
dynamometer is performing satisfactorily.
(4) Roll Speed.
(i) Frequency. Weekly checks of the roll speed measurement system shall be made, or at
intervals recommended by the dynamometer manufacturer, or as required by
inspection of quality control data, or as necessary following service to the
dynamometer.
(ii) Quality Control Limits. If roll speed checks are conducted, the measured roll speed
shall agree to within ±0.1 mph of the calibration standard. Dynamometers which
exceed the 0.1 mph limit shall be removed from service until corrective action is taken
to ensure the dynamometer is performing satisfactorily.
(5) Acceptance Criteria
(i) General. Prior to dynamometer acceptance, the dynamometer shall demonstrate
compliance with the design criteria for the load cell accuracy, power absorber curve
accuracy, roll geometry, dynamometer simulation error, electric inertia response time,
and parasitic loss measurement. These criteria are specified in §85.2226(a).
(ii) Base Inertia Verification. The base inertia of dynamometers shall be verified before
dynamometer acceptance. The base inertia weight plus individual prime weights shall
be verified for dynamometers which simulate inertia with mechanical flywheels. The
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specified base inertia shall agree with acceptance testing measurements within ±10
pounds.
(iii) Independent Speed and Distance Verification. An independent method of verifying
dynamometer roll speed and distance measurement accuracy shall be performed before
dynamometer acceptance to ensure compliance with the specifications in
§85.2226(a)(5)(v).
(c) Constant Volume Sampler
(1) Flow Calibration. The flow of the CVS shall be calibrated at six flow rates upon initial
installation, 6 months following installation, and every 12 months thereafter. SPC tracer gas
injection data may be used to verify CVS flow in lieu of the annual calibration requirement.
This data shall be made available to EPA upon request. The flow rates shall include the
nominal rated flow-rate and a rate below the rated flow-rate for both critical flow Venturis and
subsonic Venturis, and a flow-rate above the rated flow for sub-sonic Venturis. The flow
calibration points shall cover the range of variation in flow that typically occurs when testing.
A complete calibration shall be performed following repairs to the CVS that could affect flow.
(2) System Check. CVS flow calibration at the nominal CVS design flow shall be checked once
per day using a procedure equivalent to that in §86.119(c). Deviations greater than ±4% shall
result in automatic lockout of official testing until corrected. At the State's discretion, the
frequency of this may be reduced to weekly.
(3) Cleaning Flow Passages. The sample probe shall be checked at least once per month, and
cleaned if necessary in order to maintain proper sample flow. CVS venturi passages shall be
checked once per year and cleaned if necessary.
(4) Probe Flow. The indicator identifying the presence of proper probe flow for the system design
(e.g., proportional flow for CFV systems, minimum flow for time correlation of different
analyzers) shall be checked on a daily basis. Lack of proper flow shall require corrective action.
(5) Leak Check. The vacuum portion of the sample system shall be checked for leaks on a daily
basis and each time the system is serviced.
(6) System Response Time Check. The response time of each analyzer shall be checked upon
initial installation and after each repair or modification to the flow system that would reasonably
be expected to affect the response time, and at least once per week. The check shall include the
complete sample system from the sample probe to the analyzer. Statistical process control shall
be used to monitor compliance and establish quality control limits. At a minimum, response
time measurements that deviate significantly from the average response time for all CVS
systems designed to the same specification in the program shall require corrective action before
testing may resume.
(7) Mixing Tee Acceptance Test.
(i) Static Pressure Requirement. The design of the mixing tee shall be evaluated by
running the transient driving cycle on at least two vehicles, representing the high and
low ends of engine displacement and inertia. Changes in the static tailpipe pressure
with and without CVS, measured on a second-by-second basis within 3 inches of the
end of the tailpipe, shall not exceed ±1.0 inch of water.
(ii) Single Exhaust System. The ability of the mixing tee design to capture all of the
exhaust as a vehicle moves laterally from one extreme position on the dynamometer to
the other extreme shall be evaluated with back-to-back testing of three vehicles,
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representing the high and low ends of engine displacement and inertia. The back-to-
back testing shall be done with the mixing tee at the tailpipe and with an airtight
connection to the tailpipe (i.e., the mixing tee will be effectively moved downstream,
as in typical FTP testing). The difference in carbon-balance fuel economy between the
mixing tee located at the vehicle and the positive connection shall be no greater than
5%.
(iii) Dual Exhaust System. The design of the dual exhaust system shall be evaluated with
back-to-back testing of three vehicles, representing the high and low ends of engine
displacement and inertia, with an airtight connection to the tailpipe (i.e., the mixing tee
will be effectively moved downstream, as in typical FTP testing, for these qualification
tests). The difference in carbon-balance fuel economy between the two methods shall
be no greater than 5%.
(d) Analysis System
(1) Calibration Curve Generation.
(i) Initial Installation Calibration. Upon initial installation, calibration curves shall be
generated for each analyzer. If an analyzer has more than one measurement
transducer, each transducer shall be considered as a separate analyzer in the analysis
system for the purposes of curve generation and analysis system checks.
(ii) Complete Range Calibration. The calibration curve shall consider the entire range of
the analyzer as one curve.
(iii) Calibration Point Spacing. When both a low range analyzer and a high range analyzer
are used for a single gas (e.g., CO), the high range analyzer shall use at least 5
calibration points plus zero in the lower portion of the high range scale corresponding
to approximately 100% of the full-scale value of the low range analyzer. For all
analyzers, at least 5 calibration points shall be used to define the calibration curve
above the 5 lower calibration points. The calibration zero gas shall be used to set the
analyzer to zero.
Alternatively, gas dividers may be used to generate a 10-point calibration curve
employing equally spaced points.
(iv) Calibration Curve Fits. The calibration curves generated shall be a polynomial of the
best fit and no greater than 4th order, and shall fit the data within ±2.0% at each
calibration point as specified in §86.120-90, §86.122-78, §86.123-78, and §86.124-78.
(v) Mid-scale Verification. Each curve shall be verified for each analyzer with a
confirming calibration standard between 30-60% of full scale that is not used for curve
generation. Each confirming standard shall be measured by the curve within 2.5%.
(2) Spanning Frequency. The zero and up-scale span points shall be checked at 3 hour intervals
following the daily mid-scale curve check specified in §85.2234(d)(4) and adjusted if necessary.
If the up-scale span point drifts by more than 2.0% from the previous check official testing shall
be prevented and corrective action shall be taken to bring the system into compliance. If the
zero point drifts by more than 2 ppmC HC, 1 ppm NOX, 10 ppm CO, or 40 ppm CO2, official
testing shall be prevented and corrective action shall be taken to bring the system into
compliance, or the unit may be zeroed prior to each test.
(3) Limit Check. The tolerance on the initial adjustment of a change in the up-scale span point
shall be ± 2% of point on the appropriate analyzer range. A software algorithm to perform the
zero and span adjustment and subsequent calibration curve adjustment shall be used.
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Cumulative software up-scale zero and span adjustments greater than ± 10% from the latest
calibration curve shall cause official testing to be prevented and corrective action shall be taken
to bring the system into compliance. Zero and span potentiometers on the analyzer may be used
between calibrations to minimize software corrections; however, a zero and span check shall be
performed after any adjustment of a potentiometer.
(4) Daily Calibration Checks. The curve for each analyzer shall be checked and adjusted to
correctly read zero using a working zero gas, and an up-scale span gas within the tolerance in
§85.2234(d)(3), and then by reading a mid-scale span gas within 2.5% of point, on each
operating day prior to vehicle testing. If the analyzer does not read the mid-scale span point
within 2.5% of point, the analyzer shall automatically be prevented from official testing. The
up-scale span gas concentration for each analyzer may be up to 90% of full scale, and the mid-
point concentration shall correspond to approximately 15% of full scale.
(5) Monthly NOX Converter Checks. The converter efficiency of the NC>2 to NO converter shall
be checked on~a monthly basis. The check shall be equivalent to §86.123-78 (for reference see
TSD Form 305-01) except that the concentration of the NO gas shall be in the range of 75-400
ppm. Alternative methods may be used if approved by the Administrator.
This check is not required if the measurements of NO only are being performed per
85.2226(c)(2)(iv) with the NOx analyzer run in NO only mode.
(6) Monthly NO/NOX Flow Balance. The flow balance between the NO and NOX test modes shall
be checked monthly. The check may be combined with the NOX converter check as illustrated
in EPA NVFEL test laboratory Form 305-01.
This check is not required if the measurements of NO only are being performed per
85.2226(c)(2)(iv) with the NOx analyzer run in NO only mode.
(7) Monthly Calibration Checks. The basic calibration curve shall be verified monthly by the same
procedure used to generate the curve in §85.2234(d)(l), and to the same tolerances.
(8) FID Check.
(i) FID Optimization. Upon initial operation, and after maintenance to the detector, each
FID shall be checked, and adjusted if necessary, for proper peaking and
characterization using the procedures described in S AE Paper No. 770141 or by
analyzer manufacturer recommended procedures.
(ii) Methane Response. The response of each FID to a methane concentration of
approximately 50 ppm CH4 shall be checked once per month. If the response is
outside of the range of 1.00 to 1.30, corrective action shall be taken to bring the FID
response within this range. The response shall be computed by the equation in
§85.2234(d)(8)(iii). The frequency of this check may be reduced by providing 1 year
of data for each analyzer that demonstrates less frequent checks are acceptable. If less
frequent checks are used, the response check data shall be made available to EPA upon
request.
(iii) Methane Response Definition. Ratio of Methane Response = FID response to CH4
gas in ppmC /ppm CH4 in the cylinder.
(9) Mid-Span or Cross-Checks. On a quarterly basis, and whenever gas bottles are changed, each
analyzer in a given facility shall analyze a sample of a test gas. The test gas used for these cross
checks shall be a 1% NIST traceable mid-span bottle and the same bottle shall be used for all
-------
analyzers at a given facility. The analyzer shall read this mid-span gas within 2.5% of the
labeled value or the analyzer shall be taken out of service.
Alternatively, all gas bottles entering a facility shall be verified using a master bench and NIST
traceable SRM, CRM, NTRM, or ROM gases. Quarterly checks would then be performed on
each analyzer using three points at 25%, 50%, and 75% of full scale.
(10) Interference Test. The CO analyzer shall be checked for water vapor interference prior to initial
service. The interference limits in this paragraph shall apply to analyzers used with a CVS of
700 SCFM or greater. For analyzers used with lower flow rate CVS units, the allowable
interference response shall be proportionately adjusted downward.
(i) CO Analyzer. A CO instrument will be considered to be essentially free of CO2 and
water vapor interference if its response to a mixture of 3% CO2 in N2 which has been
bubbled through water at 20°C produces an equivalent CO response, as measured on
the most sensitive CO range, which is less than 1% of full scale.
(e) Gases
(1) General Requirements. Gas blends may contain up to three of any of the following
components: HC, CO, CO2, and NO. The HC component shall be propane. The diluent for
blends containing HC shall be air. The diluent for blends containing NO shall be N2- CO and
CO2 may be used with either air or N2 as the diluent. Blends containing four interest
components may be used only if approved by the Administrator. Blends containing N©2 shall
also require approval by the Administrator prior to use, except if used to perform the NOX
converter check specified in §85.2234(d)(5). Any interference effects between components in a
gas blend shall be addressed in the quality control and quality assurance process. When a gas
audit of the analytical system is performed, the auditor shall indicate whether CO2 is present in
the audit gas mixture prior to performing the audit.
(2) Calibration Gases. Gases used to generate and check calibration curves shall be traceable to a
NIST SRM, CRM, NTRM, or ROM and have a stated uncertainty to within 1% of the standard
by gas comparison methods. Calibration zero gas shall be used when using a gas divider to
generate intermediary calibration gases.
(3) Span Gases. Gases used for up-scale span adjustment, cross-checks, and for mid-scale span
checks shall be traceable to NIST SRM, CRM, NTRM, or ROM and have a stated uncertainty
to within 2% of the standard by gas comparison methods. Span gas concentrations shall be
verified immediately after a monthly calibration curve check and before being put into service.
If the reading on the span gases exceeds 2.5% of the label value, the system or gases shall be
taken out of service until corrective action is taken. When a gas divider is used to generate span
gases, the diluent gas shall not have impurities any greater than the working zero gas.
(4) Calibration Zero Gas. The impurities in the calibration zero gas shall not exceed 0.1 ppmC, 0.5
ppm CO, 1 ppm CO2, and 0.1 ppm NO. Calibration zero grade air shall be used for the FID
zero calibration gas. Calibration zero grade nitrogen or calibration zero grade air shall be used
for CO, CO2, and NOX zero calibration gases.
(5) Working Zero Gas. The impurities in working zero grade gases shall not exceed 1 ppmC, 2
ppm CO, 400 ppm CO2, and 0.3 ppm NOX. Working zero grade air or calibration zero grade
air shall be used for the FID zero span gas. Working or calibration zero grade nitrogen or air
shall be used for CO, CO2, and NOX zero span gases.
36
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(6) FID Fuel. The fuel for the FID shall consist of a mixture of 40% (+2%) hydrogen, and the
balance helium. The FID oxidizer shall be zero grade air, which can consist of artificial air
containing 18 to 21 mole percent of oxygen.
(7) Gas Naming Protocol. Gases used for calibration or auditing shall be named according to a
written established practice that has been approved by the Administrator. An accepted gas
naming procedure for I/M test purposes is the IM240 Gas Certification Protocol dated 10/27/94,
or its latest revision. Copies of the 10/27/94 document are available upon request from EPA.
(f) Overall System Performance
(1) Emission Levels. For each test lane, the average, median, 10th percentile and 90th percentile of
the composite emissions (HC, CO, CC>2, and NOX) measured shall be monitored on a monthly
basis. Differences in the monthly average of greater than ±10% by any one lane from the
facility-average or combined facility-average, or by any one facility from the combined facility-
average shall require an investigation to determine whether the single lane or facility has a
systematic equipment or operating error or difference. Where it can be determined that the
averages from one facility (or facilities) are offset from the average of the other facilities based
on the mix of vehicles tested, the ±10% limit shall be compared to the expected offset. If
systematic equipment or operating errors or differences causing the offset are found, such errors
shall be corrected. The sample period may be adjusted to assure that a reasonably random
sample of vehicles was tested in each lane.
(2) Pass/Fail Status. The average number of passing vehicles and the average number of failing
vehicles shall be monitored monthly for each test lane. Differences in the monthly average of
greater than ±15% by any one lane from the facility-average or combined facility-average, or by
any one facility from the combined facility-average shall require an investigation to determine
whether the single lane or facility has a systematic equipment or operating error or difference.
Where it can be determined that the averages from one facility (or facilities) are offset from the
average of the other facilities based on the mix of vehicles tested, the ±15% limit shall be
compared to the expected offset. If systematic equipment or operating errors or differences
causing the offset are found, such errors shall be corrected. The sample period may be adjusted
to assure that a reasonably random sample of vehicles was tested in each lane.
(g) Control Charts
(1) General Requirements. Control charts and Statistical Process Control theory shall be used to
determine, forecast, and maintain performance of each test lane, each facility, and all facilities
in a given network. The control charts shall cover the performance of key parameters in the test
system. When key parameters approach control chart limits, close monitoring of such systems
shall be initiated and corrective actions shall be taken when needed to prevent such systems
from exceeding control chart limits. If any key parameter exceeds the control chart limits,
corrective action shall be taken to bring the system into compliance. The control chart limits
specified are those values listed for the test procedures, the equipment specifications, and the
quality control specifications that cause a test to be voided or require equipment to be removed
from service. These values are "fit for use" limits, unlike a strict interpretation of SPC control
chart theory which may use tighter limits to define the process. The test facility is encouraged
to apply SPC strict control chart theory to determine when equipment or processes could be
improved. No action shall be required until the equipment or process exceeds the "fit for use
limits" specified in this section.
(2) Control Charts for Individual Test Lanes. In general, control charts for individual test lanes
shall include parameters that will allow the cause for abnormal performance of a test lane to be
pinpointed to individual systems or components. Test lane control charts shall include at a
minimum:
37
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(i) Difference between theoretical and measured coast-down times
(ii) Difference between theoretical and measured CVS flow
(iii) Up-scale span change from last up-scale span (not required if software corrections are
tracked)
(iv) Mathematical or software correction to the calibration curve as a result of an up-scale
span change (if used)
(v) Difference between the analyzer response to the daily cross-check, and the test gas
concentration
(vi) The system response time
(vii) FID CH4 response ratio
(viii) Difference between theoretical or measured values for other parameters measured
during quality assurance procedures
(3) Control Charts for Individual Facilities. Control charts for individual facilities shall consist of
the test lane control charts for each test lane at the facility.
(4) Control Charts of Individual Inspectors. Control charts for individual inspectors shall include
parameters that will allow the cause for abnormal performance to be evaluated, such as
technician IM240 driving quality.
38
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§85.2235 Evaporative Test Quality Control Requirements
(a) General Requirements
(1) Manufacturers' Recommendations. Manufacturers'recommendations for equipment
installation, calibration, and maintenance shall be followed.
(2) Statistical Process Control. SPC tracking methods shall be established for appropriate
equipment checks and custom diagnostic or verification tests.
(3) Modifications to Quality Control Requirements. Changes to the type or frequency of the quality
checks are permitted provided they are based on SPC analysis, or data from experimental
studies.
(b) Evaporative System Pressure Checks
(1) Daily Checks. The pressure check system shall be pressurized to 28±1 inch of WC and
monitored for a loss of pressure. Pressure testing shall be stopped and corrective action shall be
taken to repair the system if a loss of pressure of more than 0.4 inches of WC is observed over a
15 second period.
(2) Bi-Weekly Check. Pressure gauges or measurement devices shall be checked on a bi-weekly
basis against a reference gauge or device equal to or better than the specified performance
requirements. Deviations exceeding the specified accuracy shall require corrective action.
(c) Evaporative System Gas Cap Checks
(1) Gas Cap Tester.
(i) Daily Checks. The tester shall be verified daily by testing and correctly identifying
passing and failing reference gas caps or flow orifices as specified in
§85.2227(d)(2)(v). Reference caps and orifices shall be stored in a dirt and dust free
manner to prevent clogging and changes in flow rates. Reference caps and orifices
shall be stored at the same temperature as the cap tester to provide accurate flow
reference.
(ii) Corrective Action. Gas cap testing shall be stopped and corrective action taken to
repair the tester if passing and failing reference gas caps or flow orifices cannot be
correctly identified.
(iii) Reference Caps or Orifices - Flow Checks. Independent flow bench verification of the
reference gas caps and flow orifices shall be conducted before initial usage, and at six
month intervals, or as recommended by the cap tester manufacturer or as suggested by
analysis of quality control data. The bench flow verification results shall be traceable
to NIST.
(iv) Comparator Orifices - Flow Checks. Internal flow standard orifices for direct flow
measurement methods, or flow comparator methods, shall be traceable to a NIST
reference.
(2) Gas Cap Adapters.
(i) Leak Checks. The gas cap adapters shall be checked for visual damage daily and leak
checked weekly, or by following the recommendations of the gas cap adapters supplier.
39
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§85.2239 Test Report
(a) General Test Report Information
(1) Vehicle Description.
(i) License plate number
(ii) Vehicle identification number
(iii) Weight class
(iv) Odometer reading
(2) Date and Time. Date and end time of the tailpipe emission measurement test.
(3) Identification Information. Name or identification number of the individual performing the test
and the location of the test station and lane.
(4) Warranty Provisions. For failed vehicles, a statement indicating the availability of warranty
coverage as provided in Section 207 of the Clean Air Act.
(5) Certification. A statement certifying that the short tests were performed in accordance with
applicable regulations.
(b) Tests and Results
(1) Test Types and Standards. The test report shall indicate the types of tests performed on the
vehicle and the test standards for each. Test standards shall be displayed to the appropriate
number of significant digits as in §85.2205(a). For the IM240 the reported standards shall be
the composite test standards.
(2) Test Scores. The test report shall show the scores for each test performed. Test scores shall be
displayed to the same number of significant digits as the standards.
(3) IM240 Scores. The reported score for the IM240 shall be in units of grams per mile and shall
be selected based upon the following:
(i) Passing Scores - Composite IM240. If the emissions of any exhaust component on the
composite IM240 are below the applicable standard in §85.2205(a), then the vehicle
shall pass for that constituent and the composite score shall be reported.
(ii) Passing Scores - Phase 2. If the emissions of any exhaust component on the composite
IM240 exceed the applicable standard in §85.2205(a) but are below the Phase 2
standard, then the vehicle shall pass for that component and the Phase 2 score shall be
reported.
(iii) Failing Scores. If the emissions of any exhaust component on the composite IM240
exceed the applicable standard in §85.2205(a)(2) through §85.2205(a)(4) and exceed
the Two Ways to Pass Standard as described in §85.2205(a)(l), then the vehicle shall
fail for that component and the composite score shall be reported.
(iv) Emission Reporting. If a passing decision is made for all three exhaust components on
the IM240 before the end of the full driving cycle according to the criteria described in
§85.2205(a)(4), the passing results and reported emissions levels shall be those
obtained at the time the test is terminated. Emission levels for the IM240 shall be
reported in grams per mile calculated using the full IM240 mileage (not actual
40
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mileage). The emission standards reported shall be the composite standards (i.e., not
the fast-pass standards).
(4) Pressure Test Scores. The score(s) for the pressure test(s) shall be reported as a change in
pressure expressed in inches of water.
(5) Test Results. The test report shall indicate the pass/fail result for each test performed and the
overall result. In the case of exhaust emission tests, the report shall indicate the pass/fail status
for each component for which standards apply.
(6) Second-bv-Second Measurements. For vehicles failing the IM240, a graph showing the second-
by-second emission levels (see following example), for each exhaust component in grams per
mile equivalent. The plots of HC, CO, NOx, and CO2 are expressed in units of "gram per mile
equivalent," or:
Y = (X)*(239 seconds)/(1.959 miles)
Where: Y = Grams per mile equivalent calculated on a second by second basis
X = Grams of HC, CO, NOx, or CO2 calculated during the one second interval
(c) Recommended IM240 Second-By-Second Emissions Report
Test Number 4719
Model Year 1988
Make XXXX
Model YYYY
Cylinders 4
Transmission Auto
Vehicle Type LDGV
Test Weight 3000
TRLHP 14.7
Traction Control No
ABS No
Gas Cap Test Yes
Press Test Yes
Emission Actual
HC (gpm) 2.45
CO(gpm) 23.1
NOx (gpm) 0.71
CO2 (gpm) 279
Cut
point
0.80
15.0
2.00
n/a
The following figures provide illustrations of the recommended second-by-second emissions output.
41
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C02
gpme
100 120 140
Seconds
160 180 200 220 240
42
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§85.2241
Terms
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
(15)
(16)
(17)
(18)
(19)
(20)
(21)
(22)
(23)
(24)
(25)
(26)
(27)
(28)
(29)
(30)
(31)
(32)
(33)
(34)
(35)
(36)
(37)
(38)
(39)
(40)
ALVW:
CFV:
CH4:
C02:
CO:
CRM:
CVS:
ETW:
FID:
gpm:
GVWR:
HC:
HDGT:
hp:
Hz:
I/M:
IW:
LDGV:
LVW:
mph:
NDIR:
NIST:
NO2:
NO:
NOX:
NVFEL:
Obmph:
PLHP:
ppm:
ppmC:
psi:
RFP:
RLHP
rpm:
SCFM:
SPC:
SRM:
SSV:
TRLHP:
VCW:
(41) WC:
Adjusted Loaded Vehicle Weight: (VCW + GVWR)/2
Critical Flow Venturi
Methane
Carbon dioxide
Carbon monoxide
Certified Reference Material
Constant Volume Sampler
Equivalent Test Weight
Flame lonization Detector
Grams per mile
Gross Vehicle Weight Rating
Hydrocarbons
Heavy-Duty Gasoline-powered Truck greater than 8500 pounds GVWR
Horsepower
Cycles per Second (Hertz)
Inspection and Maintenance
Inertia Weight
Light-Duty Gasoline-powered Vehicle
Loaded Vehicle Weight: VCW + 300 pounds
Miles per hour
Non-Dispersive Infrared
National Institute for Standards and Technology
Nitrogen Dioxide
Nitrogen Oxide
Oxides of Nitrogen
National Vehicle and Fuel Emissions Laboratory
Observed dynamometer speed in mph of the loading roller, if rolls are not coupled
Parasitic horsepower loss at the observed dynamometer speed in mph
parts per million by volume
parts per million, carbon
Pounds per square inch
Request for Proposal
Road Load Horsepower
revolutions per minute
Standard cubic feet per minute
Statistical Process Control
Standard Reference Material
Subsonic venturi
Track Road-Load Horsepower
Vehicle Curb Weight: Actual vehicle weight with standard equipment and 100%
fuel fill
Pressure in inches of water column
43
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Appendix A
Guidance on the Use of Fast-Pass IM240 Standards
44
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Guidance on the Use of Fast-Pass IM240 Standards
A fast-pass decision is made by measuring the vehicle's cumulative emissions of each pollutant in each second, and
comparing them to cumulative emission fast-pass standards for each pollutant for the second of the test under consideration.
In general, if the vehicle's cumulative emissions are below a given level for all pollutants the vehicle passes. Testing
continues until decisions are made for each pollutant. Measurements of all constituents shall continue to be taken as long as
the test continues, including those constituents for which a decision has already been made.
These fast-pass standards are derived from an Arizona IM240 data set which included 3,718 tests. Fast-pass
standards for each second represent the tenth lowest cumulative emission levels in that second obtained for vehicles failing
the IM240 using the two-ways-to-pass criteria. Hence, vehicles that fall below this level are showing lower cumulative
emissions at that point in the test than the cleanest vehicles failing the full test and therefore pass. Fast-pass determinations
begin at second 30 of the IM240 cycle.
Beginning at second 109, fast pass decisions for HC and CO are based upon analysis of cumulative emissions in
phase 2, the portion of the test beginning at second 94, as well as emission levels accumulated from the beginning of the test
(the "composite" test). Fast-pass standards are derived for phase 2 of the test as described above. Since the phase 2
standards for NOX are the same as the composite, the phase 2 NOX fast-pass standards are also the same as the composite.
Scores
HC, = cumulative composite HC at time = / seconds
CO, = cumulative composite CO at time = / seconds
NOx, = cumulative composite NOx at time = / seconds
HQ,, = cumulative Phase 2 HC at time = / seconds
= cumulative Phase 2 CO at time = / seconds
= cumulative Phase 2 NOx at time = / seconds
Cumulative composite scores represent the cumulative grams of emissions from t = 0 seconds
Cumulative Phase 2 scores represent the cumulative grams of emissions from / = 109 seconds
Fast-Pass Standards
HCp, = composite HC fast-pass standard at time = / seconds
COpf = composite CO fast-pass standard at time = / seconds
NOxp, = composite NOx fast-pass standard for failing vehicles at time = / seconds
HCpbt = Phase 2 HC fast-pass standard at time = / seconds
COpbt = Phase 2 CO fast-pass standard at time = / seconds
NOxp£, = Phase 2 NOx fast-pass standard at time = t seconds
Fast-Pass Conditions
For / > 30 seconds, the vehicle shall pass if:
HC, < HC^, and CO, < CO^,, NOx,
additionally, for / > 109 seconds, the vehicle shall pass if:
RCbt < RCpbt and CObt < COpbt and NOx6, < NOx^, or
HC, < HC^, and CObt < COpbt and NOx^, < NOx^, or
HC, < HC^, and CO, < CO^, and NOx^, < NOx^, or
RCbt < HCpbt and CO, < CO^, and NOx^,
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IM240 FAST-PASS EMISSION STANDARDS
(grams)
Sec
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
Hydrocarbons
Composite Phase Composite Phase Composite Phase
222
0.80 0.50 1.25 0.75 2.00 1.25
0.124 n/a 0.247 n/a 0.407 n/a
0.126 n/a 0.253 n/a 0.415 n/a
0.129 n/a 0.258 n/a 0.423 n/a
0.135 n/a 0.263 n/a 0.436 n/a
0.140 n/a 0.268 n/a 0.451 n/a
0.146 n/a 0.277 n/a 0.464 n/a
0.150 n/a 0.283 n/a 0.468 n/a
0.153 n/a 0.293 n/a 0.475 n/a
0.156 n/a 0.297 n/a 0.487 n/a
0.160 n/a 0.298 n/a 0.506 n/a
0.165 n/a 0.313 n/a 0.530 n/a
0.169 n/a 0.320 n/a 0.549 n/a
0.172 n/a 0.327 n/a 0.569 n/a
0.173 n/a 0.342 n/a 0.588 n/a
0.177 n/a 0.360 n/a 0.609 n/a
0.197 n/a 0.376 n/a 0.621 n/a
0.200 n/a 0.389 n/a 0.636 n/a
0.208 n/a 0.408 n/a 0.649 n/a
0.221 n/a 0.423 n/a 0.666 n/a
0.232 n/a 0.434 n/a 0.679 n/a
0.235 n/a 0.444 n/a 0.696 n/a
0.238 n/a 0.454 n/a 0.712 n/a
0.240 n/a 0.465 n/a 0.727 n/a
0.242 n/a 0.472 n/a 0.745 n/a
0.246 n/a 0.478 n/a 0.760 n/a
0.249 n/a 0.485 n/a 0.776 n/a
0.252 n/a 0.493 n/a 0.797 n/a
0.261 n/a 0.500 n/a 0.814 n/a
0.271 n/a 0.505 n/a 0.826 n/a
0.276 n/a 0.514 n/a 0.837 n/a
0.278 n/a 0.537 n/a 0.849 n/a
0.280 n/a 0.540 n/a 0.862 n/a
0.282 n/a 0.543 n/a 0.872 n/a
0.283 n/a 0.546 n/a 0.887 n/a
0.284 n/a 0.551 n/a 0.895 n/a
0.285 n/a 0.559 n/a 0.903 n/a
0.286 n/a 0.567 n/a 0.925 n/a
0.288 n/a 0.575 n/a 0.933 n/a
0.291 n/a 0.588 n/a 0.945 n/a
0.294 n/a 0.595 n/a 0.959 n/a
0.296 n/a 0.601 n/a 0.970 n/a
0.298 n/a 0.606 n/a 0.980 n/a
0.300 n/a 0.610 n/a 0.988 n/a
0.302 n/a 0.617 n/a 0.997 n/a
0.304 n/a 0.631 n/a 1.022 n/a
Carbon Monoxide
Composite Phase Composite Phase Composite Phase
222
15.0 12.0 20.0 16.0 30.0 24.0
0.693 n/a 1.502 n/a 3.804 n/a
0.773 n/a 1.546 n/a 3.985 n/a
0.837 n/a 1.568 n/a 4.215 n/a
0.851 n/a 1.582 n/a 4.440 n/a
0.853 n/a 1.593 n/a 4.579 n/a
0.857 n/a 1.602 n/a 4.688 n/a
0.900 n/a 1.621 n/a 4.749 n/a
0.960 n/a 1.631 n/a 4.783 n/a
1.034 n/a 1.702 n/a 4.813 n/a
1.070 n/a 1.784 n/a 4.876 n/a
1.076 n/a 1.879 n/a 5.104 n/a
1.083 n/a 2.162 n/a 5.217 n/a
1.102 n/a 2.307 n/a 5.383 n/a
1.111 n/a 2.343 n/a 5.571 n/a
1.114 n/a 2.376 n/a 5.888 n/a
1.157 n/a 2.406 n/a 6.199 n/a
1.344 n/a 2.433 n/a 6.245 n/a
1.482 n/a 2.458 n/a 6.318 n/a
1.530 n/a 2.483 n/a 6.418 n/a
1.542 n/a 2.774 n/a 6.540 n/a
1.553 n/a 2.844 n/a 6.690 n/a
1.571 n/a 2.900 n/a 6.875 n/a
1.595 n/a 2.936 n/a 7.029 n/a
1.633 n/a 3.133 n/a 7.129 n/a
1.685 n/a 3.304 n/a 7.359 n/a
1.689 n/a 3.407 n/a 7.722 n/a
1.693 n/a 3.456 n/a 8.017 n/a
1.700 n/a 3.480 n/a 8.249 n/a
1.723 n/a 3.518 n/a 8.425 n/a
1.852 n/a 3.560 n/a 8.563 n/a
1.872 n/a 3.593 n/a 8.686 n/a
1.872 n/a 3.628 n/a 8.804 n/a
1.872 n/a 3.641 n/a 8.916 n/a
1.900 n/a 3.655 n/a 9.025 n/a
1.917 n/a 3.680 n/a 9.138 n/a
1.944 n/a 3.700 n/a 9.250 n/a
2.000 n/a 3.728 n/a 9.354 n/a
2.060 n/a 3.857 n/a 9.457 n/a
2.064 n/a 3.894 n/a 9.575 n/a
2.076 n/a 3.943 n/a 9.728 n/a
2.104 n/a 3.983 n/a 9.938 n/a
2.117 n/a 4.009 n/a 10.140 n/a
2.125 n/a 4.023 n/a 10.222 n/a
2.130 n/a 4.023 n/a 10.261 n/a
2.138 n/a 4.053 n/a 10.278 n/a
Oxides of
Nitrogen
2.0 2.5 3.0
0.167 0.262 0.419
0.177 0.275 0.425
0.188 0.301 0.431
0.214 0.317 0.449
0.232 0.327 0.476
0.240 0.330 0.497
0.243 0.332 0.515
0.245 0.334 0.516
0.246 0.336 0.519
0.246 0.337 0.527
0.250 0.354 0.542
0.260 0.366 0.560
0.277 0.410 0.598
0.311 0.414 0.616
0.328 0.438 0.645
0.343 0.477 0.670
0.359 0.506 0.691
0.373 0.518 0.716
0.383 0.522 0.735
0.385 0.526 0.765
0.400 0.554 0.802
0.410 0.574 0.836
0.434 0.587 0.868
0.464 0.601 0.890
0.472 0.615 0.918
0.480 0.629 0.936
0.491 0.643 0.947
0.500 0.667 0.958
0.506 0.678 0.970
0.509 0.683 0.982
0.512 0.686 0.994
0.516 0.693 1.019
0.519 0.699 1.042
0.523 0.703 1.049
0.529 0.707 1.058
0.533 0.711 1.062
0.535 0.716 1.064
0.540 0.721 1.070
0.551 0.726 1.077
0.563 0.742 1.085
0.575 0.759 1.092
0.588 0.773 1.101
0.600 0.784 1.111
0.603 0.790 1.121
0.604 0.794 1.131
46
-------
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
0.307
0.308
0.308
0.308
0.314
0.320
0.324
0.327
0.329
0.333
0.336
0.339
0.343
0.347
0.350
0.356
0.358
0.360
0.363
0.367
0.370
0.372
0.376
0.388
0.396
0.405
0.410
0.411
0.412
0.413
0.421
0.428
0.430
0.455
0.459
0.462
0.464
0.466
0.468
0.471
0.488
0.513
0.538
0.561
0.577
0.580
0.586
0.594
0.603
0.610
0.615
0.624
0.628
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
0.015
0.017
0.021
0.024
0.024
0.025
0.026
0.029
0.032
0.035
0.035
0.036
0.038
0.040
0.041
0.042
0.042
0.042
0.045
0.643
0.651
0.659
0.667
0.676
0.681
0.685
0.689
0.694
0.700
0.705
0.709
0.713
0.717
0.721
0.724
0.727
0.729
0.731
0.734
0.740
0.748
0.759
0.771
0.783
0.793
0.810
0.823
0.836
0.853
0.871
0.887
0.899
0.931
0.947
0.957
0.965
0.971
0.977
0.983
1.003
1.030
1.041
1.050
1.052
1.055
1.061
1.071
1.081
1.091
1.102
1.110
1.116
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
0.040
0.047
0.052
0.056
0.061
0.064
0.072
0.081
0.082
0.083
0.092
0.094
0.097
0.100
0.103
0.106
0.108
0.110
0.112
1.037 n/a
1.051 n/a
1.064 n/a
1.075 n/a
1.087 n/a
1.097 n/a
1.105 n/a
1.114 n/a
1.136 n/a
1.160 n/a
1.182 n/a
1.201 n/a
1.217 n/a
1.233 n/a
1.248 n/a
1.262 n/a
1.271 n/a
1.279 n/a
1.287 n/a
1.295 n/a
1.302 n/a
1.309 n/a
1.316 n/a
1.325 n/a
1.339 n/a
1.356 n/a
1.365 n/a
1.378 n/a
1.397 n/a
1.420 n/a
1.445 n/a
1.470 n/a
1.491 n/a
1.506 n/a
1.517 0.151
1.528 0.159
1.542 0.172
1.559 0.186
1.578 0.199
1.594 0.207
1.605 0.216
1.615 0.229
1.625 0.235
1.642 0.240
1.670 0.245
1.694 0.261
1.705 0.267
1.717 0.277
1.732 0.287
1.747 0.298
1.763 0.308
1.779 0.316
1.795 0.322
2.152
2.170
2.188
2.200
2.212
2.212
2.221
2.222
2.227
2.236
2.243
2.262
2.271
2.284
2.299
2.308
2.326
2.330
2.331
2.344
2.347
2.355
2.395
2.451
2.508
2.590
2.660
2.749
2.913
3.162
3.170
3.197
3.288
3.419
3.587
3.595
3.640
3.740
3.868
3.877
3.934
4.015
4.061
4.063
4.079
4.140
4.185
4.199
4.205
4.212
4.232
4.298
4.344
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
0.168
0.173
0.237
0.266
0.280
0.291
0.314
0.331
0.345
0.350
0.356
0.367
0.388
0.407
0.463
0.480
0.506
0.518
0.522
4.063
4.077
4.225
4.243
4.260
4.282
4.322
4.398
4.482
4.515
4.518
4.520
4.522
4.522
4.523
4.526
4.527
4.527
4.528
4.528
4.528
4.529
4.575
4.703
4.805
4.886
4.957
5.104
5.340
5.496
5.625
5.815
6.473
7.037
7.419
7.643
7.759
7.824
7.889
7.960
8.024
8.076
8.111
8.130
8.148
8.211
8.478
8.548
8.561
8.568
8.572
8.584
8.592
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
0.246
0.257
0.286
0.379
0.425
0.457
0.477
0.494
0.504
0.512
0.519
0.529
0.529
0.530
0.531
0.532
0.533
0.548
0.610
10.290 n/a
10.715 n/a
10.790 n/a
10.844 n/a
10.921 n/a
11.010 n/a
11.090 n/a
11.136 n/a
11.136 n/a
11.165 n/a
11.191 n/a
11.205 n/a
11.211 n/a
11.211 n/a
11.211 n/a
11.211 n/a
11.220 n/a
11.294 n/a
11.332 n/a
11.355 n/a
11.383 n/a
11.410 n/a
11.433 n/a
11.516 n/a
11.820 n/a
12.104 n/a
12.344 n/a
12.781 n/a
13.472 n/a
14.405 n/a
14.808 n/a
14.965 n/a
15.121 n/a
15.372 n/a
15.530 1.113
15.687 1.213
16.018 1.344
16.527 1.399
16.810 1.520
16.961 1.640
17.120 1.684
17.135 1.693
17.249 1.786
17.451 2.007
17.509 2.084
17.605 2.179
17.734 2.264
18.049 2.328
18.447 2.375
18.592 2.437
18.657 2.543
18.796 2.593
18.952 2.641
0.613 0.799 1.141
0.624 0.809 1.159
0.646 0.821 1.164
0.651 0.833 1.186
0.659 0.839 1.221
0.673 0.844 1.260
0.696 0.857 1.268
0.706 0.870 1.272
0.715 0.883 1.277
0.724 0.894 1.288
0.737 0.902 1.310
0.747 0.907 1.319
0.748 0.910 1.320
0.748 0.912 1.337
0.748 0.913 1.348
0.748 0.914 1.361
0.748 0.915 1.366
0.748 0.916 1.369
0.748 0.917 1.373
0.748 0.918 1.375
0.748 0.919 1.377
0.748 0.920 1.379
0.748 0.921 1.381
0.748 0.922 1.383
0.751 0.924 1.385
0.764 0.929 1.399
0.789 0.941 1.405
0.822 0.970 1.466
0.867 1.027 1.485
0.905 1.093 1.546
0.925 1.155 1.623
0.955 1.234 1.699
0.985 1.275 1.760
0.993 1.305 1.788
0.995 1.320 1.798
0.996 1.332 1.842
1.010 1.346 1.864
1.028 1.358 1.888
1.034 1.378 1.905
1.044 1.406 1.920
1.059 1.426 1.926
1.075 1.438 1.939
1.080 1.448 1.958
1.080 1.460 1.972
1.081 1.462 1.981
1.091 1.467 1.987
1.096 1.476 1.991
1.111 1.494 1.996
1.122 1.505 2.012
1.135 1.517 2.040
1.138 1.546 2.060
1.139 1.569 2.069
1.139 1.586 2.092
47
-------
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
0.632
0.637
0.641
0.643
0.644
0.645
0.647
0.651
0.658
0.663
0.666
0.668
0.670
0.672
0.675
0.678
0.681
0.684
0.686
0.688
0.690
0.692
0.694
0.696
0.698
0.700
0.702
0.704
0.706
0.708
0.710
0.712
0.716
0.750
0.784
0.805
0.840
0.853
0.874
0.903
0.910
0.914
0.916
0.919
0.931
0.948
0.983
1.018
1.027
1.035
1.051
1.074
1.084
0.046
0.046
0.049
0.050
0.052
0.054
0.054
0.054
0.055
0.055
0.056
0.059
0.061
0.061
0.061
0.063
0.064
0.065
0.066
0.067
0.068
0.069
0.070
0.071
0.072
0.073
0.073
0.074
0.077
0.079
0.082
0.082
0.086
0.095
0.107
0.115
0.122
0.127
0.159
0.186
0.189
0.200
0.220
0.236
0.247
0.257
0.267
0.283
0.295
0.312
0.318
0.323
0.337
1.121 0.114 1.810 0.329 4.361 0.525 8.596 0.614 19.137 2.663 1.139 1.596 2.114
1.125 0.116 1.823 0.338 4.366 0.528 8.597 0.622 19.329 2.672 1.139 1.603 2.132
1.128 0.118 1.835 0.346 4.369 0.530 8.601 0.631 19.519 2.676 1.139 1.605 2.144
1.130 0.120 1.845 0.354 4.372 0.530 8.605 0.640 19.707 2.683 1.139 1.606 2.152
1.132 0.122 1.854 0.356 4.435 0.534 8.608 0.646 19.882 2.817 1.139 1.607 2.157
1.134 0.123 1.862 0.357 4.523 0.550 8.626 0.650 19.905 2.992 1.139 1.607 2.160
1.135 0.124 1.870 0.359 4.524 0.554 8.650 0.652 20.049 3.111 1.139 1.608 2.163
1.143 0.127 1.883 0.362 4.525 0.590 8.660 0.738 20.460 3.234 1.139 1.614 2.165
1.147 0.130 1.888 0.364 4.531 0.616 8.767 0.754 20.746 3.304 1.160 1.616 2.168
1.156 0.134 1.896 0.368 4.534 0.639 9.029 0.780 21.068 3.310 1.174 1.631 2.171
1.163 0.139 1.911 0.378 4.542 0.653 9.238 0.795 21.380 3.320 1.183 1.643 2.186
1.186 0.146 1.928 0.391 4.553 0.662 9.389 0.804 21.748 3.354 1.197 1.656 2.235
1.253 0.149 1.949 0.402 4.554 0.683 9.493 0.810 22.046 3.436 1.223 1.673 2.298
1.262 0.151 1.969 0.408 4.554 0.696 9.583 0.815 22.348 3.443 1.255 1.703 2.333
1.271 0.153 1.982 0.422 4.554 0.708 9.626 0.818 22.397 3.452 1.272 1.739 2.373
1.277 0.155 1.999 0.428 4.554 0.721 9.669 0.821 22.407 3.490 1.286 1.767 2.406
1.283 0.157 2.011 0.432 4.554 0.739 9.716 0.825 22.417 3.552 1.304 1.774 2.416
1.291 0.162 2.022 0.434 4.554 0.742 9.763 0.840 22.922 3.588 1.307 1.785 2.420
1.294 0.164 2.035 0.439 4.554 0.743 9.809 0.847 22.951 3.600 1.312 1.806 2.424
1.296 0.166 2.043 0.450 4.554 0.745 9.852 0.855 22.976 3.616 1.317 1.830 2.435
1.298 0.168 2.049 0.460 4.554 0.748 9.885 0.865 23.017 3.627 1.321 1.844 2.455
1.303 0.169 2.063 0.467 4.554 0.751 9.932 0.874 23.073 3.636 1.325 1.845 2.471
1.316 0.170 2.085 0.472 4.554 0.762 9.986 0.891 23.161 3.676 1.328 1.846 2.484
1.330 0.171 2.104 0.480 4.556 0.789 10.039 0.914 23.218 3.882 1.332 1.852 2.495
1.342 0.172 2.117 0.491 4.556 0.790 10.072 0.929 23.253 4.011 1.338 1.868 2.509
1.348 0.173 2.127 0.503 4.565 0.794 10.090 0.937 23.337 4.047 1.344 1.877 2.522
1.353 0.175 2.138 0.505 4.612 0.799 10.105 0.942 23.425 4.067 1.350 1.879 2.533
1.362 0.178 2.152 0.515 4.834 0.805 10.146 0.949 23.534 4.081 1.357 1.886 2.541
1.365 0.180 2.168 0.522 5.702 0.842 10.245 1.375 23.652 4.116 1.365 1.900 2.552
1.366 0.189 2.186 0.527 5.841 0.990 10.397 1.576 23.739 4.251 1.379 1.910 2.589
1.373 0.198 2.205 0.537 6.170 1.038 10.923 1.943 24.606 5.099 1.414 1.936 2.631
1.397 0.203 2.224 0.549 6.670 1.357 11.970 2.820 25.615 5.383 1.466 1.954 2.704
1.423 0.207 2.242 0.568 7.425 1.455 13.421 3.281 26.073 6.362 1.514 1.986 2.758
1.440 0.214 2.268 0.586 8.379 1.546 15.289 3.483 28.496 7.926 1.559 2.050 2.802
1.452 0.221 2.308 0.610 9.648 1.824 15.912 3.620 29.772 8.429 1.591 2.131 2.904
1.465 0.229 2.352 0.648 10.918 2.746 16.530 4.168 31.056 9.201 1.641 2.235 2.960
1.509 0.247 2.406 0.677 12.157 3.073 17.622 4.338 33.351 10.825 1.719 2.320 3.027
1.533 0.274 2.421 0.699 12.731 3.633 18.366 4.682 34.890 12.291 1.777 2.395 3.127
1.555 0.309 2.435 0.720 12.831 4.505 19.869 5.633 35.937 13.366 1.832 2.488 3.187
1.576 0.318 2.470 0.738 12.892 4.952 20.711 6.137 37.012 14.428 1.919 2.563 3.306
1.598 0.322 2.501 0.767 12.932 5.254 22.319 6.853 37.892 15.318 1.972 2.645 3.384
1.618 0.333 2.537 0.828 13.702 5.730 23.751 7.136 39.028 15.699 2.013 2.746 3.467
1.636 0.343 2.571 0.855 14.139 6.051 24.842 7.320 40.406 16.073 2.100 2.778 3.565
1.666 0.356 2.625 0.869 14.964 6.333 25.410 7.685 41.379 16.475 2.200 2.792 3.640
1.685 0.385 2.657 0.885 15.704 6.490 25.798 8.052 42.033 17.158 2.251 2.810 3.718
1.726 0.409 2.683 0.900 16.253 6.796 26.122 8.344 42.432 17.532 2.270 2.847 3.781
1.742 0.433 2.701 0.941 16.907 7.205 26.353 8.602 42.742 17.965 2.301 2.874 3.827
1.756 0.453 2.717 0.979 17.655 8.151 26.638 8.898 43.399 18.242 2.318 2.905 3.852
1.769 0.463 2.732 1.002 18.020 8.230 27.219 9.251 43.895 18.283 2.335 2.950 3.903
1.784 0.507 2.756 1.025 18.349 8.584 27.279 10.253 44.227 18.480 2.349 3.001 3.930
1.802 0.523 2.781 1.047 18.671 8.800 27.320 10.828 44.926 19.576 2.387 3.047 3.970
1.822 0.528 2.811 1.065 18.972 8.847 27.352 10.933 45.256 20.015 2.423 3.104 4.015
1.843 0.541 2.853 1.089 19.228 8.913 27.822 11.060 45.553 20.203 2.462 3.173 4.074
48
-------
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
1.099
1.121
1.132
1.152
1.161
1.168
1.175
1.181
1.188
1.203
1.219
1.233
1.251
1.255
1.258
1.265
1.280
1.293
1.301
1.313
1.324
1.332
1.341
1.357
1.375
1.392
1.408
1.422
1.433
1.443
1.453
1.463
1.468
1.470
1.474
1.478
1.481
1.484
1.487
1.490
1.493
1.504
1.522
1.547
1.549
1.562
1.574
1.579
1.584
1.589
1.590
1.596
1.598
0.345
0.350
0.359
0.387
0.398
0.400
0.402
0.405
0.418
0.429
0.442
0.457
0.473
0.487
0.501
0.510
0.512
0.514
0.516
0.518
0.527
0.540
0.547
0.553
0.559
0.563
0.567
0.571
0.575
0.579
0.595
0.605
0.614
0.622
0.627
0.638
0.643
0.643
0.645
0.651
0.655
0.663
0.671
0.675
0.684
0.694
0.701
0.702
0.708
0.708
0.709
0.710
0.710
1.864
1.884
1.896
1.915
1.940
1.958
1.972
1.985
1.991
1.993
1.995
2.001
2.015
2.031
2.047
2.063
2.079
2.094
2.109
2.122
2.130
2.137
2.157
2.172
2.194
2.222
2.245
2.268
2.279
2.288
2.301
2.316
2.332
2.345
2.354
2.362
2.368
2.376
2.384
2.391
2.395
2.400
2.405
2.409
2.413
2.415
2.417
2.419
2.420
2.421
2.423
2.425
2.427
0.549
0.559
0.571
0.584
0.598
0.613
0.624
0.629
0.629
0.638
0.648
0.659
0.663
0.671
0.681
0.693
0.709
0.725
0.740
0.754
0.767
0.775
0.787
0.795
0.803
0.854
0.859
0.872
0.892
0.896
0.903
0.924
0.938
0.941
0.951
0.966
0.979
0.980
0.981
1.005
1.016
1.022
1.028
1.035
1.041
1.045
1.051
1.055
1.059
1.062
1.063
1.063
1.063
2.898
2.946
2.988
3.023
3.057
3.076
3.101
3.120
3.136
3.151
3.163
3.209
3.223
3.237
3.263
3.302
3.338
3.372
3.390
3.428
3.470
3.493
3.509
3.522
3.533
3.550
3.578
3.607
3.630
3.658
3.701
3.745
3.778
3.814
3.825
3.835
3.844
3.853
3.864
3.874
3.891
3.928
3.966
4.008
4.010
4.012
4.016
4.019
4.057
4.065
4.071
4.073
4.075
1.109
1.133
1.158
1.184
1.209
1.222
1.231
1.239
1.254
1.278
1.300
1.313
1.324
1.340
1.367
1.387
1.402
1.417
1.432
1.446
1.460
1.477
1.492
1.501
1.510
1.522
1.561
1.585
1.597
1.607
1.627
1.645
1.656
1.663
1.669
1.674
1.685
1.700
1.704
1.706
1.709
1.711
1.714
1.718
1.721
1.723
1.726
1.729
1.731
1.733
1.735
1.743
1.749
20.123
20.405
20.754
21.684
21.955
22.650
22.989
23.535
23.876
24.018
24.464
24.685
24.931
25.188
25.468
25.627
25.746
25.850
25.974
26.141
26.225
26.338
26.547
26.818
27.052
27.393
27.501
27.632
27.803
27.953
28.205
28.543
28.997
29.000
29.005
29.081
29.281
29.483
29.734
29.803
29.821
29.847
29.862
29.873
30.008
30.126
30.127
30.127
30.208
30.314
30.323
30.325
30.368
9.122 28.763
9.532 29.402
10.256 29.971
10.862 30.276
10.996 30.988
11.206 31.095
11.514 31.314
11.894 31.833
12.019 32.239
12.170 32.547
12.517 32.855
12.598 33.153
12.625 33.444
12.653 33.482
12.777 33.516
12.906 33.549
12.989 33.653
13.060 33.973
13.165 34.159
13.242 34.191
13.412 34.250
13.662 34.469
13.773 34.716
13.942 34.969
14.090 35.144
14.224 35.418
14.426 35.766
14.498 35.949
14.776 36.010
14.907 36.548
14.916 37.179
15.014 37.651
15.221 38.041
15.472 38.591
15.555 38.852
15.652 38.861
15.969 38.926
16.028 39.194
16.375 39.474
16.487 39.668
16.524 39.781
16.578 39.890
16.684 39.954
16.755 39.984
16.770 39.989
16.805 39.990
16.865 39.990
16.960 39.990
16.960 39.991
16.962 40.012
16.988 40.061
17.072 40.116
17.094 40.249
11.188
11.345
11.733
12.598
12.953
13.213
14.131
14.839
15.137
15.138
15.141
15.595
15.658
15.704
15.729
16.058
16.987
17.064
17.073
17.153
17.332
17.406
17.641
17.922
18.484
18.553
18.658
18.953
19.266
19.309
19.731
19.902
20.012
20.260
20.739
21.346
21.810
22.001
22.290
22.324
22.343
22.522
22.661
22.666
22.667
22.668
22.669
22.670
22.671
22.671
22.672
22.673
22.673
45.753 20.433
46.210 21.025
47.017 21.882
48.185 22.204
48.741 22.859
49.462 23.533
50.313 24.281
51.285 25.078
52.076 25.276
52.857 25.578
52.876 25.859
53.067 25.985
53.777 26.153
54.242 26.582
54.489 27.067
54.601 27.456
54.912 27.805
55.588 28.070
56.266 28.590
56.617 28.914
56.863 29.063
57.204 29.502
57.371 29.697
57.487 29.713
57.728 29.783
58.097 29.942
58.572 30.284
59.024 30.755
59.321 31.287
59.715 31.549
60.045 31.820
60.453 32.250
60.935 32.546
61.307 32.808
61.666 33.060
62.148 33.204
62.532 33.341
62.546 33.414
62.559 33.514
62.570 33.640
62.846 33.692
63.097 33.711
63.150 33.733
63.150 33.770
63.150 33.796
63.150 33.810
63.150 33.821
63.150 33.839
63.150 33.865
63.150 33.894
63.150 33.918
63.150 33.944
63.150 33.985
2.503 3.238 4.159
2.545 3.302 4.230
2.586 3.372 4.286
2.627 3.452 4.334
2.673 3.545 4.388
2.749 3.648 4.447
2.804 3.701 4.505
2.851 3.759 4.561
2.894 3.821 4.625
2.931 3.870 4.696
2.971 3.892 4.731
3.020 3.914 4.780
3.077 3.955 4.837
3.132 3.997 4.876
3.185 4.035 4.928
3.219 4.089 4.972
3.268 4.146 5.025
3.299 4.206 5.104
3.350 4.243 5.189
3.406 4.295 5.275
3.466 4.351 5.336
3.497 4.398 5.366
3.514 4.410 5.387
3.517 4.419 5.427
3.519 4.426 5.444
3.523 4.429 5.447
3.545 4.453 5.477
3.570 4.486 5.520
3.600 4.542 5.560
3.619 4.598 5.603
3.639 4.638 5.657
3.686 4.715 5.698
3.732 4.774 5.762
3.791 4.829 5.827
3.833 4.872 5.849
3.890 4.931 5.884
3.932 4.960 5.908
3.960 4.963 5.921
3.997 4.965 5.931
4.013 4.968 5.939
4.035 4.971 5.947
4.038 4.974 5.952
4.050 4.977 5.955
4.066 4.979 5.957
4.070 4.980 5.959
4.072 4.981 5.961
4.072 4.982 5.963
4.073 4.983 5.966
4.073 4.984 5.971
4.073 4.985 5.977
4.073 4.986 5.984
4.074 4.987 5.990
4.074 4.988 5.997
49
-------
234
235
236
237
238
239
1.604 0.711 2.429 1.064 4.077 1.753
1.610 0.712 2.430 1.064 4.079 1.757
1.612 0.712 2.431 1.066 4.081 1.762
1.613 0.712 2.432 1.069 4.083 1.767
1.614 0.713 2.433 1.072 4.084 1.772
1.615 0.716 2.434 1.075 4.085 1.776
30.411 17.184 40.253 22.673 63.153 34.014
30.416 17.187 40.290 22.674 63.159 34.032
30.428 17.188 40.385 22.675 63.173 34.051
30.430 17.189 40.488 22.675 63.193 34.067
30.452 17.241 40.720 22.675 63.214 34.079
30.488 17.370 40.763 22.677 63.233 34.085
4.075 4.989 6.004
4.075 4.990 6.012
4.076 4.991 6.024
4.076 4.992 6.037
4.076 4.993 6.049
4.076 4.994 6.060
50
-------
Appendix B
Alternative Fast-Pass IM240 Standards
51
-------
Alternative Fast-Pass IM240 Standards
Corresponding to Composite Start-up Emission Standards
in §85.2205(a)(2)(i) and §85.2205(a)(2)(ii)
Light Duty Vehicles
Sec
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
Low Al
1981-1982
HC CO NOx
0.330 4.189 0.250
0.342 4.278 0.267
0.353 4.366 0.283
0.364 4.455 0.300
0.375 4.544 0.316
0.386 4.633 0.333
0.398 4.728 0.336
0.409 4.823 0.339
0.420 4.917 0.342
0.431 5.012 0.345
0.443 5.107 0.348
0.458 5.429 0.371
0.474 5.751 0.394
0.489 6.073 0.418
0.505 6.395 0.441
0.521 6.717 0.465
0.535 6.985 0.480
0.550 7.254 0.496
0.565 7.522 0.512
0.580 7.791 0.527
0.594 8.060 0.543
0.611 8.511 0.567
0.628 8.962 0.590
0.644 9.413 0.613
0.661 9.865 0.637
0.678 10.316 0.660
0.691 10.818 0.675
0.705 11.320 0.689
0.718 11.822 0.703
0.731 12.325 0.718
0.745 12.827 0.732
0.758 13.228 0.743
0.772 13.629 0.754
0.786 14.029 0.764
0.799 14.430 0.775
0.813 14.831 0.786
0.827 15.046 0.794
0.841 15.261 0.803
titude Low Altitii
1983-1990
HC CO NOx
0.330 1.941 0.251
0.342 1.983 0.268
0.353 2.025 0.285
0.365 2.067 0.302
0.376 2.108 0.320
0.388 2.150 0.337
0.399 2.230 0.339
0.410 2.310 0.342
0.420 2.390 0.344
0.431 2.471 0.347
0.442 2.551 0.349
0.458 2.738 0.373
0.473 2.926 0.397
0.489 3.114 0.422
0.505 3.302 0.446
0.520 3.489 0.470
0.536 3.589 0.486
0.552 3.688 0.501
0.568 3.787 0.517
0.584 3.887 0.533
0.600 3.986 0.549
0.617 4.029 0.571
0.633 4.072 0.594
0.649 4.115 0.616
0.665 4.157 0.638
0.681 4.200 0.661
0.696 4.263 0.676
0.710 4.326 0.691
0.725 4.388 0.707
0.740 4.451 0.722
0.754 4.514 0.737
0.767 4.589 0.748
0.780 4.664 0.758
0.794 4.740 0.769
0.807 4.815 0.780
0.820 4.891 0.790
0.833 4.945 0.799
0.846 4.999 0.808
ide Low Altiti
1991-1995
HC CO NOx
0.174 1.307 0.222
0.179 1.329 0.246
0.184 1.350 0.270
0.189 1.372 0.294
0.194 1.394 0.318
0.199 1.416 0.342
0.201 1.453 0.345
0.203 1.490 0.348
0.205 1.527 0.350
0.207 1.565 0.353
0.209 1.602 0.356
0.214 1.642 0.373
0.219 1.682 0.390
0.224 1.722 0.407
0.228 1.763 0.425
0.233 1.803 0.442
0.238 1.867 0.465
0.244 1.932 0.487
0.250 1.997 0.510
0.255 2.061 0.533
0.261 2.126 0.555
0.268 2.152 0.573
0.275 2.179 0.590
0.282 2.205 0.608
0.290 2.232 0.625
0.297 2.258 0.643
0.302 2.348 0.654
0.306 2.437 0.666
0.311 2.526 0.677
0.316 2.616 0.688
0.320 2.705 0.700
0.323 2.726 0.707
0.326 2.746 0.714
0.329 2.767 0.722
0.332 2.787 0.729
0.335 2.808 0.736
0.340 2.812 0.742
0.345 2.816 0.747
ide High Altitude
1982
HC CO NOx
0.330 7.391 0.250
0.342 7.667 0.267
0.353 7.944 0.283
0.364 8.220 0.300
0.375 8.497 0.316
0.386 8.773 0.333
0.398 9.011 0.336
0.409 9.249 0.339
0.420 9.488 0.342
0.431 9.726 0.345
0.443 9.964 0.348
0.458 10.527 0.371
0.474 11.090 0.394
0.489 11.652 0.418
0.505 12.215 0.441
0.521 12.778 0.465
0.535 13.265 0.480
0.550 13.751 0.496
0.565 14.238 0.512
0.580 14.724 0.527
0.594 15.211 0.543
0.611 15.550 0.567
0.628 15.889 0.590
0.644 16.228 0.613
0.661 16.567 0.637
0.678 16.907 0.660
0.691 17.199 0.675
0.705 17.492 0.689
0.718 17.785 0.703
0.731 18.078 0.718
0.745 18.371 0.732
0.758 18.609 0.743
0.772 18.847 0.754
0.786 19.085 0.764
0.799 19.323 0.775
0.813 19.562 0.786
0.827 19.887 0.794
0.841 20.213 0.803
52
-------
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
0.855 15.476 0.811
0.869 15.692 0.820
0.883 15.907 0.828
0.894 16.118 0.838
0.905 16.330 0.848
0.917 16.542 0.858
0.928 16.753 0.868
0.939 16.965 0.878
0.953 17.199 0.891
0.967 17.432 0.904
0.981 17.666 0.917
0.994 17.900 0.930
1.008 18.133 0.944
1.019 18.182 0.951
1.031 18.231 0.958
1.042 18.280 0.965
1.053 18.329 0.972
1.065 18.378 0.979
1.072 18.393 0.980
1.079 18.408 0.981
1.086 18.423 0.982
1.093 18.438 0.983
1.099 18.453 0.983
1.107 18.467 0.984
1.114 18.481 0.985
1.121 18.495 0.985
1.128 18.509 0.986
1.135 18.523 0.986
1.149 18.681 0.992
1.162 18.840 0.997
1.176 18.998 1.002
1.189 19.157 1.008
1.203 19.315 1.013
1.223 20.090 1.049
1.244 20.864 1.085
1.264 21.639 1.121
1.285 22.414 1.157
1.305 23.189 1.193
1.319 23.461 1.224
1.333 23.733 1.255
1.346 24.006 1.286
1.360 24.278 1.317
1.374 24.550 1.348
1.385 24.846 1.356
1.396 25.141 1.363
0.859 5.053 0.817
0.872 5.107 0.826
0.885 5.162 0.835
0.896 5.226 0.846
0.906 5.291 0.857
0.917 5.356 0.868
0.928 5.421 0.878
0.939 5.486 0.889
0.952 5.553 0.900
0.965 5.620 0.911
0.978 5.687 0.922
0.991 5.754 0.933
1.004 5.821 0.944
1.015 5.842 0.951
1.026 5.863 0.959
1.037 5.883 0.966
1.048 5.904 0.973
1.059 5.925 0.980
1.067 5.970 0.981
1.075 6.015 0.982
1.083 6.060 0.982
1.091 6.105 0.983
1.099 6.151 0.984
1.106 6.185 0.985
1.114 6.219 0.986
1.122 6.253 0.986
1.129 6.287 0.987
1.137 6.321 0.988
1.150 6.489 0.993
1.163 6.657 0.999
1.176 6.825 1.004
1.189 6.992 1.009
1.202 7.160 1.014
1.224 7.269 1.049
1.245 7.378 1.084
1.266 7.487 1.119
1.287 7.596 1.154
1.309 7.705 1.189
1.323 7.835 1.215
1.338 7.965 1.241
1.352 8.095 1.267
1.367 8.225 1.293
1.382 8.355 1.319
1.394 8.414 1.327
1.406 8.472 1.336
0.350 2.820 0.753
0.355 2.825 0.758
0.360 2.829 0.764
0.364 2.847 0.783
0.367 2.865 0.802
0.371 2.884 0.822
0.375 2.902 0.841
0.378 2.921 0.860
0.387 2.982 0.874
0.396 3.044 0.888
0.405 3.106 0.902
0.414 3.167 0.916
0.423 3.229 0.930
0.428 3.240 0.945
0.432 3.250 0.959
0.437 3.261 0.973
0.441 3.271 0.987
0.445 3.281 1.002
0.448 3.290 1.003
0.452 3.298 1.004
0.455 3.306 1.005
0.458 3.315 1.006
0.462 3.323 1.007
0.463 3.360 1.008
0.464 3.397 1.008
0.465 3.434 1.009
0.466 3.470 1.009
0.468 3.507 1.010
0.472 3.536 1.011
0.477 3.565 1.012
0.481 3.594 1.013
0.486 3.623 1.014
0.490 3.651 1.015
0.499 3.685 1.042
0.509 3.719 1.069
0.518 3.753 1.097
0.527 3.787 1.124
0.537 3.821 1.151
0.541 3.842 1.194
0.545 3.863 1.237
0.548 3.884 1.280
0.552 3.904 1.323
0.556 3.925 1.366
0.562 3.931 1.368
0.568 3.937 1.371
0.855 20.539 0.811
0.869 20.865 0.820
0.883 21.191 0.828
0.894 21.396 0.838
0.905 21.602 0.848
0.917 21.808 0.858
0.928 22.013 0.868
0.939 22.219 0.878
0.953 22.685 0.891
0.967 23.151 0.904
0.981 23.617 0.917
0.994 24.083 0.930
1.008 24.549 0.944
1.019 24.570 0.951
1.031 24.591 0.958
1.042 24.612 0.965
1.053 24.633 0.972
1.065 24.654 0.979
1.072 24.666 0.980
1.079 24.678 0.981
1.086 24.690 0.982
1.093 24.703 0.983
1.099 24.715 0.983
1.107 24.737 0.984
1.114 24.758 0.985
1.121 24.780 0.985
1.128 24.801 0.986
1.135 24.823 0.986
1.149 25.193 0.992
1.162 25.563 0.997
1.176 25.933 1.002
1.189 26.303 1.008
1.203 26.672 1.013
1.223 27.821 1.049
1.244 28.969 1.085
1.264 30.117 1.121
1.285 31.265 1.157
1.305 32.414 1.193
1.319 33.103 1.224
1.333 33.792 1.255
1.346 34.481 1.286
1.360 35.170 1.317
1.374 35.859 1.348
1.385 36.177 1.356
1.396 36.495 1.363
-------
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
1.407 25.437 1.371
1.417 25.732 1.378
1.428 26.028 1.386
1.437 26.045 1.388
1.446 26.062 1.389
1.455 26.079 1.391
1.464 26.096 1.393
1.472 26.114 1.394
1.488 26.293 1.408
1.503 26.472 1.422
1.518 26.651 1.435
1.534 26.830 1.449
1.549 27.010 1.463
1.559 27.151 1.471
1.569 27.292 1.479
1.579 27.433 1.487
1.590 27.575 1.495
1.600 27.716 1.502
1.612 27.878 1.506
1.624 28.040 1.509
1.635 28.202 1.512
1.647 28.365 1.515
1.659 28.527 1.519
1.676 28.833 1.542
1.693 29.140 1.566
1.709 29.446 1.589
1.726 29.753 1.613
1.743 30.060 1.636
1.756 30.160 1.651
1.770 30.260 1.666
1.783 30.361 1.681
1.797 30.461 1.696
1.810 30.562 1.711
1.822 30.592 1.720
1.834 30.622 1.730
1.846 30.653 1.740
1.858 30.683 1.750
1.869 30.713 1.760
1.880 30.741 1.767
1.890 30.768 1.775
1.900 30.796 1.783
1.910 30.823 1.791
1.920 30.850 1.798
1.949 32.415 1.828
1.977 33.980 1.858
1.418 8.531 1.345
1.430 8.590 1.354
1.442 8.649 1.363
1.451 8.735 1.364
1.460 8.821 1.365
1.469 8.907 1.366
1.479 8.992 1.368
1.488 9.078 1.369
1.501 9.152 1.385
1.514 9.227 1.401
1.527 9.301 1.417
1.540 9.375 1.434
1.553 9.449 1.450
1.563 9.519 1.458
1.572 9.590 1.467
1.582 9.661 1.475
1.592 9.731 1.484
1.601 9.802 1.492
1.615 9.849 1.496
1.628 9.895 1.500
1.642 9.942 1.504
1.655 9.989 1.508
1.669 10.035 1.512
1.685 10.104 1.534
1.700 10.173 1.557
1.716 10.241 1.580
1.732 10.310 1.603
1.747 10.378 1.626
1.762 10.506 1.640
1.777 10.633 1.655
1.791 10.761 1.669
1.806 10.888 1.684
1.821 11.016 1.699
1.830 11.101 1.709
1.840 11.187 1.720
1.850 11.273 1.730
1.860 11.359 1.741
1.869 11.445 1.752
1.879 11.504 1.759
1.890 11.564 1.767
1.900 11.624 1.775
1.910 11.683 1.783
1.920 11.743 1.790
1.945 12.434 1.821
1.971 13.125 1.852
0.574 3.943 1.374
0.580 3.949 1.377
0.586 3.956 1.380
0.590 3.975 1.380
0.593 3.995 1.381
0.597 4.015 1.382
0.600 4.035 1.383
0.604 4.055 1.383
0.610 4.152 1.400
0.615 4.250 1.417
0.621 4.348 1.433
0.627 4.445 1.450
0.632 4.543 1.466
0.636 4.567 1.470
0.639 4.592 1.473
0.642 4.617 1.476
0.645 4.641 1.479
0.648 4.666 1.482
0.653 4.685 1.483
0.657 4.704 1.485
0.661 4.724 1.486
0.666 4.743 1.488
0.670 4.762 1.489
0.678 4.785 1.507
0.685 4.807 1.524
0.693 4.830 1.541
0.700 4.853 1.559
0.708 4.875 1.576
0.716 4.886 1.592
0.723 4.897 1.608
0.731 4.908 1.624
0.738 4.918 1.640
0.746 4.929 1.656
0.751 4.954 1.663
0.755 4.979 1.671
0.760 5.004 1.679
0.765 5.029 1.687
0.770 5.054 1.694
0.775 5.060 1.711
0.780 5.065 1.727
0.785 5.070 1.743
0.791 5.075 1.760
0.796 5.080 1.776
0.819 5.150 1.813
0.842 5.220 1.850
1.407 36.813 1.371
1.417 37.132 1.378
1.428 37.450 1.386
1.437 37.554 1.388
1.446 37.658 1.389
1.455 37.761 1.391
1.464 37.865 1.393
1.472 37.969 1.394
1.488 38.310 1.408
1.503 38.650 1.422
1.518 38.990 1.435
1.534 39.330 1.449
1.549 39.671 1.463
1.559 39.865 1.471
1.569 40.059 1.479
1.579 40.254 1.487
1.590 40.448 1.495
1.600 40.642 1.502
1.612 40.790 1.506
1.624 40.937 1.509
1.635 41.084 1.512
1.647 41.231 1.515
1.659 41.379 1.519
1.676 42.023 1.542
1.693 42.668 1.566
1.709 43.312 1.589
1.726 43.957 1.613
1.743 44.602 1.636
1.756 45.010 1.651
1.770 45.419 1.666
1.783 45.828 1.681
1.797 46.237 1.696
1.810 46.646 1.711
1.822 46.945 1.720
1.834 47.244 1.730
1.846 47.544 1.740
1.858 47.843 1.750
1.869 48.143 1.760
1.880 48.423 1.767
1.890 48.704 1.775
1.900 48.984 1.783
1.910 49.265 1.791
1.920 49.545 1.798
1.949 50.517 1.828
1.977 51.489 1.858
54
-------
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
2.006 35.545 1.888
2.034 37.110 1.918
2.063 38.674 1.948
2.105 41.040 2.043
2.147 43.405 2.138
2.190 45.770 2.234
2.232 48.136 2.329
2.275 50.501 2.424
2.304 52.979 2.509
2.333 55.458 2.593
2.362 57.937 2.678
2.391 60.415 2.762
2.420 62.894 2.847
2.451 63.874 2.890
2.481 64.855 2.933
2.512 65.835 2.976
2.542 66.815 3.019
2.573 67.796 3.062
2.598 68.919 3.122
2.623 70.042 3.181
2.648 71.165 3.240
2.674 72.287 3.300
2.699 73.410 3.359
2.726 74.714 3.432
2.753 76.017 3.504
2.780 77.320 3.576
2.807 78.623 3.648
2.834 79.927 3.720
2.861 81.488 3.804
2.888 83.049 3.889
2.915 84.611 3.973
2.942 86.172 4.057
2.969 87.733 4.141
2.994 88.668 4.196
3.019 89.603 4.250
3.044 90.538 4.304
3.070 91.473 4.358
3.095 92.407 4.412
3.120 93.768 4.485
3.145 95.129 4.558
3.169 96.490 4.630
3.194 97.851 4.703
3.219 99.212 4.775
3.242 99.878 4.821
3.266 100.544 4.867
1.996 13.816 1.883
2.022 14.507 1.913
2.047 15.198 1.944
2.092 16.627 2.038
2.137 18.056 2.133
2.182 19.485 2.227
2.227 20.914 2.321
2.272 22.343 2.415
2.300 23.672 2.502
2.328 25.002 2.589
2.356 26.331 2.676
2.385 27.660 2.763
2.413 28.989 2.849
2.442 29.484 2.892
2.472 29.978 2.934
2.502 30.473 2.976
2.532 30.967 3.019
2.562 31.462 3.061
2.588 32.216 3.119
2.615 32.970 3.178
2.641 33.725 3.236
2.668 34.479 3.295
2.694 35.233 3.353
2.718 35.950 3.424
2.743 36.666 3.495
2.767 37.382 3.567
2.791 38.099 3.638
2.816 38.815 3.709
2.843 39.562 3.795
2.869 40.309 3.880
2.896 41.056 3.965
2.923 41.803 4.051
2.950 42.550 4.136
2.975 43.279 4.190
3.001 44.008 4.243
3.027 44.737 4.297
3.052 45.466 4.351
3.078 46.195 4.404
3.105 46.747 4.477
3.132 47.299 4.549
3.159 47.852 4.622
3.186 48.404 4.694
3.213 48.957 4.767
3.234 49.204 4.812
3.255 49.451 4.858
0.865 5.290 1.887
0.888 5.360 1.924
0.911 5.430 1.961
0.951 7.045 2.030
0.992 8.661 2.099
1.032 10.276 2.168
1.073 11.891 2.237
1.113 13.506 2.306
1.163 14.131 2.357
1.213 14.755 2.409
1.263 15.380 2.460
1.313 16.004 2.512
1.363 16.628 2.564
1.386 16.692 2.603
1.410 16.756 2.643
1.433 16.820 2.683
1.457 16.883 2.723
1.480 16.947 2.762
1.494 17.044 2.809
1.508 17.141 2.856
1.522 17.238 2.903
1.536 17.335 2.949
1.550 17.431 2.996
1.565 17.453 3.040
1.580 17.475 3.084
1.595 17.497 3.129
1.610 17.519 3.173
1.624 17.540 3.217
1.639 17.816 3.277
1.654 18.091 3.337
1.668 18.366 3.397
1.683 18.641 3.457
1.697 18.916 3.518
1.711 19.891 3.565
1.724 20.866 3.612
1.737 21.840 3.658
1.750 22.815 3.705
1.763 23.790 3.752
1.778 24.992 3.794
1.793 26.194 3.836
1.808 27.396 3.877
1.823 28.597 3.919
1.838 29.799 3.960
1.858 29.975 4.004
1.877 30.152 4.047
2.006 52.461 1.888
2.034 53.433 1.918
2.063 54.406 1.948
2.105 56.279 2.043
2.147 58.152 2.138
2.190 60.026 2.234
2.232 61.899 2.329
2.275 63.773 2.424
2.304 65.726 2.509
2.333 67.678 2.593
2.362 69.631 2.678
2.391 71.584 2.762
2.420 73.536 2.847
2.451 75.553 2.890
2.481 77.570 2.933
2.512 79.587 2.976
2.542 81.604 3.019
2.573 83.621 3.062
2.598 85.074 3.122
2.623 86.528 3.181
2.648 87.981 3.240
2.674 89.434 3.300
2.699 90.888 3.359
2.726 92.421 3.432
2.753 93.953 3.504
2.780 95.486 3.576
2.807 97.019 3.648
2.834 98.552 3.720
2.861 100.583 3.804
2.888 102.615 3.889
2.915 104.646 3.973
2.942 106.677 4.057
2.969 108.709 4.141
2.994 110.057 4.196
3.019 111.405 4.250
3.044 112.753 4.304
3.070 114.101 4.358
3.095 115.449 4.412
3.120 116.561 4.485
3.145 117.674 4.558
3.169 118.786 4.630
3.194 119.899 4.703
3.219 121.011 4.775
3.242 121.695 4.821
3.266 122.378 4.867
55
-------
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
3.289 101.210 4.914
3.312 101.876 4.960
3.335 102.542 5.006
3.362 103.507 5.037
3.388 104.472 5.069
3.415 105.437 5.101
3.441 106.402 5.132
3.468 107.366 5.164
3.488 108.519 5.234
3.509 109.671 5.304
3.530 110.823 5.374
3.550 111.976 5.444
3.571 113.128 5.514
3.591 113.763 5.564
3.612 114.398 5.613
3.632 115.033 5.663
3.652 115.668 5.713
3.672 116.304 5.763
3.693 116.644 5.775
3.714 116.984 5.787
3.736 117.324 5.799
3.757 117.663 5.811
3.778 118.003 5.823
3.795 118.158 5.828
3.811 118.312 5.833
3.828 118.466 5.838
3.845 118.621 5.842
3.862 118.775 5.847
3.873 118.885 5.852
3.884 118.995 5.856
3.896 119.105 5.860
3.907 119.215 5.865
3.918 119.325 5.869
3.924 119.407 5.874
3.930 119.488 5.878
3.935 119.570 5.883
3.941 119.651 5.887
3.947 119.733 5.892
3.277 49.698 4.904
3.298 49.945 4.950
3.320 50.192 4.996
3.346 50.698 5.029
3.373 51.205 5.063
3.399 51.711 5.097
3.426 52.218 5.130
3.452 52.724 5.164
3.472 53.327 5.233
3.492 53.931 5.303
3.513 54.534 5.372
3.533 55.137 5.442
3.553 55.740 5.511
3.571 56.057 5.559
3.589 56.373 5.606
3.608 56.689 5.654
3.626 57.005 5.701
3.644 57.321 5.749
3.669 57.474 5.761
3.693 57.626 5.773
3.717 57.779 5.785
3.741 57.931 5.797
3.766 58.084 5.809
3.782 58.158 5.814
3.798 58.232 5.820
3.815 58.307 5.825
3.831 58.381 5.830
3.848 58.455 5.835
3.858 58.534 5.840
3.868 58.612 5.845
3.879 58.690 5.850
3.889 58.769 5.855
3.900 58.847 5.860
3.907 58.990 5.865
3.913 59.132 5.869
3.920 59.275 5.874
3.927 59.418 5.878
3.934 59.560 5.883
1.897 30.328 4.090
1.916 30.504 4.133
1.936 30.680 4.176
1.948 30.747 4.193
1.961 30.813 4.209
1.973 30.879 4.225
1.986 30.946 4.241
1.998 31.012 4.257
2.006 32.744 4.311
2.015 34.476 4.365
2.023 36.207 4.419
2.031 37.939 4.473
2.039 39.671 4.527
2.044 39.822 4.565
2.048 39.973 4.602
2.053 40.125 4.640
2.058 40.276 4.677
2.062 40.427 4.715
2.076 40.526 4.724
2.089 40.626 4.732
2.103 40.725 4.741
2.117 40.825 4.750
2.130 40.924 4.759
2.160 40.962 4.764
2.190 41.000 4.770
2.219 41.038 4.775
2.249 41.076 4.781
2.278 41.114 4.786
2.285 41.142 4.790
2.292 41.171 4.794
2.299 41.199 4.797
2.306 41.228 4.801
2.313 41.256 4.805
2.315 41.285 4.808
2.318 41.313 4.812
2.320 41.341 4.815
2.322 41.369 4.818
2.325 41.397 4.822
3.289 123.062 4.914
3.312 123.745 4.960
3.335 124.429 5.006
3.362 125.599 5.037
3.388 126.769 5.069
3.415 127.939 5.101
3.441 129.109 5.132
3.468 130.279 5.164
3.488 132.009 5.234
3.509 133.740 5.304
3.530 135.470 5.374
3.550 137.201 5.444
3.571 138.931 5.514
3.591 140.070 5.564
3.612 141.208 5.613
3.632 142.347 5.663
3.652 143.485 5.713
3.672 144.624 5.763
3.693 144.903 5.775
3.714 145.182 5.787
3.736 145.462 5.799
3.757 145.741 5.811
3.778 146.020 5.823
3.795 146.177 5.828
3.811 146.334 5.833
3.828 146.491 5.838
3.845 146.648 5.842
3.862 146.805 5.847
3.873 147.057 5.852
3.884 147.308 5.856
3.896 147.560 5.860
3.907 147.812 5.865
3.918 148.064 5.869
3.924 148.450 5.874
3.930 148.837 5.878
3.935 149.223 5.883
3.941 149.609 5.887
3.947 149.996 5.892
56
-------
Alternative Fast-Pass IM240 Standards
Corresponding to Composite Start-up Emission Standards in §85.2205(a)(2)(iv)
Light Duty Truck 1&2
Sec
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
1982-1983
HC CO NOx
1.064 14.776 0.562
1.091 15.338 0.610
1.118 15.900 0.657
1.145 16.462 0.705
1.172 17.023 0.752
1.199 17.585 0.800
1.237 17.834 0.804
1.275 18.084 0.808
1.313 18.333 0.813
1.351 18.582 0.817
1.389 18.832 0.822
1.459 19.867 0.869
1.529 20.902 0.915
1.599 21.937 0.962
1.669 22.972 1.009
1.738 24.008 1.056
1.784 24.572 1.098
1.830 25.136 1.140
1.876 25.701 1.182
1.922 26.265 1.224
1.968 26.830 1.266
2.020 27.642 1.305
2.072 28.454 1.343
2.124 29.266 1.381
2.176 30.079 1.420
2.228 30.891 1.458
2.265 31.485 1.490
2.302 32.078 1.522
2.340 32.672 1.555
2.377 33.266 1.587
2.415 33.860 1.619
2.451 34.449 1.637
2.487 35.037 1.656
2.523 35.626 1.674
2.559 36.215 1.693
2.595 36.804 1.711
2.639 37.463 1.737
2.683 38.122 1.763
2.728 38.782 1.789
1984-1987
HC CO NOx
0.585 10.661 0.513
0.609 11.033 0.551
0.633 11.405 0.590
0.657 11.777 0.629
0.681 12.149 0.667
0.705 12.521 0.706
0.730 12.895 0.711
0.754 13.269 0.716
0.779 13.643 0.721
0.803 14.018 0.727
0.828 14.392 0.732
0.854 15.098 0.796
0.880 15.805 0.861
0.907 16.511 0.925
0.933 17.217 0.989
0.959 17.924 1.053
0.989 18.458 1.096
1.019 18.992 1.138
1.050 19.526 1.180
1.080 20.060 1.223
1.110 20.594 1.265
1.146 21.719 1.294
1.182 22.845 1.324
1.218 23.970 1.353
1.254 25.095 1.382
1.290 26.221 1.411
1.310 26.449 1.449
1.330 26.677 1.486
1.350 26.905 1.523
1.370 27.133 1.560
1.390 27.361 1.597
1.405 27.372 1.611
1.420 27.383 1.625
1.434 27.393 1.639
1.449 27.404 1.653
1.464 27.415 1.667
1.497 28.054 1.699
1.530 28.694 1.732
1.563 29.333 1.765
1988-1990
HC CO NOx
0.585 10.661 0.298
0.609 11.033 0.319
0.633 11.405 0.340
0.657 11.777 0.361
0.681 12.149 0.382
0.705 12.521 0.403
0.730 12.895 0.407
0.754 13.269 0.410
0.779 13.643 0.414
0.803 14.018 0.418
0.828 14.392 0.422
0.854 15.098 0.451
0.880 15.805 0.479
0.907 16.511 0.508
0.933 17.217 0.536
0.959 17.924 0.565
0.989 18.458 0.587
1.019 18.992 0.609
1.050 19.526 0.631
1.080 20.060 0.652
1.110 20.594 0.674
1.146 21.719 0.701
1.182 22.845 0.728
1.218 23.970 0.755
1.254 25.095 0.782
1.290 26.221 0.809
1.310 26.449 0.826
1.330 26.677 0.842
1.350 26.905 0.859
1.370 27.133 0.876
1.390 27.361 0.892
1.405 27.372 0.903
1.420 27.383 0.915
1.434 27.393 0.926
1.449 27.404 0.938
1.464 27.415 0.949
1.497 28.054 0.960
1.530 28.694 0.972
1.563 29.333 0.983
1991
HC CO NOx
0.477 5.069 0.254
0.494 5.129 0.270
0.512 5.189 0.285
0.529 5.249 0.300
0.547 5.309 0.316
0.564 5.369 0.331
0.582 5.562 0.334
0.601 5.755 0.336
0.619 5.948 0.339
0.637 6.142 0.341
0.656 6.335 0.344
0.681 6.890 0.368
0.707 7.445 0.392
0.732 7.999 0.416
0.758 8.554 0.440
0.783 9.109 0.464
0.799 9.593 0.480
0.816 10.076 0.496
0.832 10.560 0.512
0.848 11.044 0.528
0.864 11.527 0.543
0.891 12.038 0.563
0.917 12.549 0.582
0.943 13.059 0.601
0.969 13.570 0.621
0.995 14.081 0.640
1.015 14.438 0.653
1.035 14.796 0.666
1.055 15.154 0.679
1.075 15.512 0.692
1.095 15.870 0.705
1.109 16.268 0.714
1.124 16.667 0.723
1.138 17.066 0.732
1.153 17.465 0.741
1.167 17.863 0.750
1.182 18.249 0.759
1.196 18.635 0.768
1.211 19.020 0.777
57
-------
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
2.772 39.441 1.815
2.817 40.100 1.841
2.859 40.631 1.862
2.901 41.161 1.884
2.943 41.692 1.906
2.985 42.222 1.928
3.027 42.753 1.950
3.061 43.694 1.978
3.096 44.636 2.007
3.130 45.577 2.035
3.165 46.519 2.063
3.200 47.461 2.092
3.237 47.831 2.111
3.275 48.201 2.130
3.313 48.571 2.149
3.351 48.941 2.168
3.389 49.311 2.187
3.432 49.503 2.189
3.475 49.694 2.192
3.518 49.886 2.194
3.562 50.077 2.197
3.605 50.269 2.199
3.645 50.447 2.200
3.686 50.626 2.201
3.727 50.805 2.202
3.767 50.984 2.203
3.808 51.162 2.204
3.853 51.779 2.212
3.898 52.395 2.219
3.943 53.012 2.227
3.988 53.628 2.234
4.033 54.245 2.242
4.081 55.131 2.322
4.128 56.016 2.403
4.175 56.902 2.484
4.223 57.788 2.565
4.270 58.674 2.646
4.300 59.222 2.721
4.331 59.771 2.797
4.361 60.319 2.872
4.391 60.868 2.948
4.421 61.416 3.023
4.449 61.935 3.038
4.476 62.455 3.053
4.503 62.974 3.067
1.596 29.972 1.797
1.629 30.612 1.830
1.650 31.097 1.854
1.672 31.583 1.878
1.694 32.068 1.902
1.715 32.554 1.925
1.737 33.039 1.949
1.760 33.193 1.977
1.782 33.347 2.005
1.805 33.501 2.033
1.828 33.655 2.061
1.851 33.809 2.089
1.872 34.035 2.111
1.894 34.261 2.132
1.915 34.488 2.154
1.937 34.714 2.175
1.958 34.941 2.197
1.973 35.115 2.200
1.988 35.289 2.203
2.002 35.463 2.206
2.017 35.637 2.209
2.032 35.811 2.212
2.044 35.968 2.213
2.056 36.125 2.214
2.068 36.282 2.215
2.081 36.440 2.216
2.093 36.597 2.217
2.111 36.968 2.227
2.129 37.339 2.236
2.147 37.710 2.245
2.165 38.081 2.254
2.183 38.453 2.263
2.221 40.429 2.342
2.258 42.405 2.420
2.295 44.382 2.498
2.333 46.358 2.576
2.370 48.335 2.654
2.404 49.060 2.740
2.437 49.785 2.826
2.471 50.511 2.912
2.504 51.236 2.998
2.538 51.962 3.084
2.560 52.113 3.101
2.582 52.265 3.118
2.604 52.417 3.136
1.596 29.972 0.994
1.629 30.612 1.005
1.650 31.097 1.016
1.672 31.583 1.028
1.694 32.068 1.039
1.715 32.554 1.051
1.737 33.039 1.062
1.760 33.193 1.074
1.782 33.347 1.085
1.805 33.501 1.096
1.828 33.655 1.108
1.851 33.809 1.119
1.872 34.035 1.131
1.894 34.261 1.144
1.915 34.488 1.156
1.937 34.714 1.169
1.958 34.941 1.181
1.973 35.115 1.182
1.988 35.289 1.182
2.002 35.463 1.183
2.017 35.637 1.184
2.032 35.811 1.185
2.044 35.968 1.186
2.056 36.125 1.187
2.068 36.282 1.188
2.081 36.440 1.189
2.093 36.597 1.190
2.111 36.968 1.195
2.129 37.339 1.201
2.147 37.710 1.207
2.165 38.081 1.213
2.183 38.453 1.218
2.221 40.429 1.259
2.258 42.405 1.299
2.295 44.382 1.340
2.333 46.358 1.380
2.370 48.335 1.421
2.404 49.060 1.458
2.437 49.785 1.495
2.471 50.511 1.531
2.504 51.236 1.568
2.538 51.962 1.605
2.560 52.113 1.615
2.582 52.265 1.624
2.604 52.417 1.634
1.225 19.406 0.786
1.239 19.792 0.795
1.255 19.906 0.805
1.271 20.020 0.815
1.287 20.134 0.825
1.303 20.248 0.835
1.318 20.362 0.845
1.331 20.782 0.859
1.344 21.202 0.874
1.357 21.623 0.888
1.370 22.043 0.902
1.382 22.463 0.916
1.407 22.571 0.925
1.431 22.678 0.934
1.455 22.786 0.942
1.480 22.894 0.951
1.504 23.001 0.960
1.531 23.112 0.961
1.558 23.223 0.963
1.586 23.334 0.964
1.613 23.445 0.966
1.640 23.556 0.967
1.654 23.558 0.968
1.668 23.560 0.968
1.682 23.562 0.968
1.696 23.564 0.969
1.710 23.567 0.969
1.727 23.924 0.978
1.744 24.282 0.987
1.762 24.639 0.996
1.779 24.997 1.004
1.796 25.355 1.013
1.819 25.871 1.045
1.842 26.387 1.076
1.865 26.903 1.107
1.887 27.419 1.139
1.910 27.935 1.170
1.936 28.221 1.201
1.962 28.506 1.232
1.988 28.792 1.263
2.014 29.077 1.294
2.040 29.363 1.325
2.057 29.405 1.332
2.074 29.447 1.338
2.090 29.489 1.344
58
-------
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
4.531 63.493 3.082
4.558 64.013 3.097
4.600 64.559 3.099
4.642 65.105 3.102
4.684 65.651 3.105
4.726 66.197 3.108
4.768 66.743 3.111
4.804 67.600 3.134
4.840 68.458 3.156
4.876 69.315 3.179
4.911 70.173 3.202
4.947 71.030 3.224
4.983 71.729 3.241
5.019 72.427 3.257
5.055 73.126 3.274
5.091 73.825 3.290
5.126 74.523 3.307
5.178 75.331 3.311
5.230 76.139 3.316
5.282 76.947 3.321
5.334 77.755 3.326
5.386 78.563 3.331
5.468 79.372 3.365
5.549 80.181 3.398
5.630 80.990 3.431
5.712 81.798 3.464
5.793 82.607 3.498
5.825 83.486 3.536
5.856 84.365 3.575
5.888 85.245 3.613
5.920 86.124 3.652
5.951 87.003 3.690
5.975 87.915 3.718
5.998 88.827 3.745
6.022 89.739 3.772
6.046 90.652 3.800
6.069 91.564 3.827
6.099 92.475 3.852
6.129 93.387 3.877
6.159 94.298 3.901
6.189 95.209 3.926
6.219 96.121 3.951
6.313 97.599 4.030
6.407 99.077 4.110
6.501 100.555 4.190
2.625 52.569 3.153
2.647 52.721 3.170
2.673 52.723 3.173
2.698 52.724 3.175
2.723 52.726 3.178
2.749 52.728 3.181
2.774 52.729 3.184
2.799 53.168 3.206
2.824 53.606 3.229
2.850 54.044 3.251
2.875 54.483 3.274
2.900 54.921 3.296
2.920 55.078 3.310
2.941 55.236 3.323
2.961 55.393 3.337
2.981 55.551 3.350
3.001 55.708 3.364
3.027 55.921 3.370
3.052 56.134 3.376
3.078 56.346 3.382
3.103 56.559 3.388
3.129 56.771 3.394
3.167 57.854 3.432
3.206 58.937 3.469
3.244 60.020 3.507
3.283 61.102 3.544
3.322 62.185 3.582
3.342 62.366 3.639
3.363 62.548 3.697
3.383 62.729 3.754
3.404 62.910 3.811
3.425 63.091 3.869
3.453 63.539 3.892
3.482 63.987 3.916
3.510 64.435 3.939
3.539 64.883 3.963
3.568 65.331 3.986
3.595 65.704 4.000
3.623 66.077 4.014
3.650 66.450 4.029
3.677 66.823 4.043
3.705 67.197 4.057
3.767 69.206 4.117
3.829 71.215 4.176
3.891 73.225 4.236
2.625 52.569 1.644
2.647 52.721 1.653
2.673 52.723 1.656
2.698 52.724 1.658
2.723 52.726 1.661
2.749 52.728 1.663
2.774 52.729 1.666
2.799 53.168 1.684
2.824 53.606 1.703
2.850 54.044 1.722
2.875 54.483 1.741
2.900 54.921 1.759
2.920 55.078 1.770
2.941 55.236 1.780
2.961 55.393 1.790
2.981 55.551 1.800
3.001 55.708 1.811
3.027 55.921 1.813
3.052 56.134 1.816
3.078 56.346 1.819
3.103 56.559 1.822
3.129 56.771 1.825
3.167 57.854 1.851
3.206 58.937 1.877
3.244 60.020 1.903
3.283 61.102 1.929
3.322 62.185 1.955
3.342 62.366 1.977
3.363 62.548 1.999
3.383 62.729 2.021
3.404 62.910 2.043
3.425 63.091 2.065
3.453 63.539 2.074
3.482 63.987 2.082
3.510 64.435 2.090
3.539 64.883 2.098
3.568 65.331 2.106
3.595 65.704 2.117
3.623 66.077 2.129
3.650 66.450 2.141
3.677 66.823 2.152
3.705 67.197 2.164
3.767 69.206 2.205
3.829 71.215 2.247
3.891 73.225 2.289
2.107 29.531 1.350
2.124 29.573 1.357
2.152 29.865 1.359
2.179 30.157 1.361
2.207 30.449 1.363
2.234 30.741 1.365
2.262 31.033 1.368
2.276 31.230 1.383
2.290 31.428 1.399
2.304 31.625 1.415
2.318 31.823 1.431
2.332 32.020 1.446
2.355 32.099 1.453
2.377 32.178 1.460
2.399 32.256 1.468
2.422 32.335 1.475
2.444 32.413 1.482
2.464 32.638 1.484
2.485 32.862 1.487
2.505 33.086 1.490
2.525 33.310 1.492
2.545 33.534 1.495
2.573 34.147 1.520
2.600 34.760 1.546
2.628 35.373 1.571
2.655 35.985 1.596
2.682 36.598 1.622
2.702 36.880 1.639
2.722 37.162 1.656
2.742 37.444 1.673
2.762 37.727 1.691
2.782 38.009 1.708
2.797 38.632 1.717
2.811 39.255 1.726
2.825 39.878 1.735
2.839 40.501 1.743
2.853 41.124 1.752
2.868 41.450 1.765
2.883 41.776 1.778
2.898 42.102 1.791
2.913 42.428 1.803
2.927 42.754 1.816
2.969 44.233 1.849
3.011 45.712 1.882
3.053 47.191 1.915
59
-------
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
6.595 102.033 4.269
6.689 103.511 4.349
7.010 107.552 4.542
7.331 111.593 4.736
7.652 115.634 4.930
7.972 119.676 5.123
8.293 123.717 5.317
8.576 125.252 5.496
8.859 126.786 5.676
9.142 128.321 5.855
9.425 129.855 6.034
9.708 131.390 6.213
9.788 132.095 6.318
9.868 132.801 6.422
9.948 133.506 6.527
10.028 134.211 6.632
10.107 134.917 6.736
10.174 137.703 6.876
10.242 140.490 7.016
10.309 143.276 7.155
10.376 146.063 7.295
10.443 148.849 7.435
10.506 152.900 7.603
10.570 156.950 7.772
10.634 161.001 7.941
10.698 165.051 8.110
10.761 169.102 8.279
10.836 171.850 8.477
10.911 174.598 8.675
10.986 177.345 8.873
11.061 180.093 9.071
11.136 182.841 9.269
11.307 184.591 9.422
11.477 186.341 9.576
11.648 188.091 9.730
11.819 189.841 9.884
11.990 191.591 10.038
12.067 194.037 10.193
12.144 196.482 10.348
12.221 198.927 10.503
12.298 201.373 10.658
12.376 203.818 10.813
12.463 204.868 10.912
12.551 205.918 11.012
12.639 206.967 11.111
3.953 75.234 4.295
4.015 77.243 4.355
4.078 79.985 4.551
4.142 82.727 4.747
4.205 85.469 4.943
4.268 88.211 5.139
4.332 90.953 5.335
4.380 93.266 5.516
4.428 95.579 5.696
4.477 97.892 5.876
4.525 100.205 6.056
4.573 102.517 6.237
4.618 103.813 6.345
4.664 105.109 6.452
4.709 106.404 6.560
4.754 107.700 6.668
4.799 108.995 6.776
4.858 110.733 6.910
4.917 112.471 7.045
4.977 114.209 7.179
5.036 115.946 7.313
5.095 117.684 7.447
5.158 119.775 7.621
5.221 121.866 7.795
5.284 123.956 7.969
5.347 126.047 8.143
5.411 128.138 8.318
5.428 129.673 8.499
5.446 131.209 8.681
5.463 132.745 8.862
5.481 134.281 9.043
5.499 135.816 9.225
5.561 137.198 9.386
5.623 138.580 9.547
5.686 139.961 9.708
5.748 141.343 9.869
5.810 142.724 10.030
5.828 144.052 10.188
5.845 145.381 10.346
5.863 146.709 10.504
5.880 148.037 10.662
5.898 149.365 10.820
5.942 150.214 10.948
5.986 151.063 11.075
6.029 151.912 11.203
3.953 75.234 2.330
4.015 77.243 2.372
4.078 79.985 2.472
4.142 82.727 2.571
4.205 85.469 2.671
4.268 88.211 2.770
4.332 90.953 2.870
4.380 93.266 2.961
4.428 95.579 3.053
4.477 97.892 3.144
4.525 100.205 3.235
4.573 102.517 3.327
4.618 103.813 3.373
4.664 105.109 3.420
4.709 106.404 3.467
4.754 107.700 3.513
4.799 108.995 3.560
4.858 110.733 3.626
4.917 112.471 3.692
4.977 114.209 3.758
5.036 115.946 3.824
5.095 117.684 3.889
5.158 119.775 3.979
5.221 121.866 4.069
5.284 123.956 4.159
5.347 126.047 4.248
5.411 128.138 4.338
5.428 129.673 4.443
5.446 131.209 4.547
5.463 132.745 4.652
5.481 134.281 4.756
5.499 135.816 4.861
5.561 137.198 4.932
5.623 138.580 5.003
5.686 139.961 5.074
5.748 141.343 5.146
5.810 142.724 5.217
5.828 144.052 5.301
5.845 145.381 5.385
5.863 146.709 5.469
5.880 148.037 5.553
5.898 149.365 5.637
5.942 150.214 5.692
5.986 151.063 5.746
6.029 151.912 5.801
3.095 48.670 1.948
3.136 50.149 1.981
3.182 51.569 2.071
3.227 52.988 2.162
3.272 54.408 2.252
3.318 55.828 2.343
3.363 57.247 2.434
3.410 58.958 2.509
3.458 60.670 2.584
3.505 62.381 2.659
3.552 64.092 2.735
3.600 65.804 2.810
3.644 66.939 2.863
3.688 68.075 2.916
3.732 69.210 2.969
3.776 70.345 3.022
3.821 71.481 3.075
3.856 73.077 3.130
3.891 74.674 3.185
3.927 76.271 3.240
3.962 77.867 3.295
3.997 79.464 3.350
4.024 81.282 3.430
4.050 83.100 3.509
4.077 84.919 3.589
4.104 86.737 3.668
4.131 88.555 3.748
4.154 90.333 3.841
4.178 92.110 3.934
4.202 93.888 4.026
4.225 95.665 4.119
4.249 97.442 4.212
4.285 98.856 4.274
4.321 100.271 4.336
4.357 101.685 4.398
4.393 103.099 4.459
4.430 104.513 4.521
4.460 106.134 4.589
4.490 107.755 4.658
4.520 109.376 4.726
4.550 110.997 4.795
4.580 112.617 4.863
4.623 113.207 4.906
4.666 113.796 4.949
4.709 114.385 4.993
60
-------
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
12.726 208.017 11.211
12.814 209.067 11.310
12.891 211.915 11.381
12.969 214.764 11.452
13.046 217.612 11.523
13.124 220.460 11.594
13.201 223.309 11.665
13.243 226.365 11.862
13.285 229.421 12.060
13.327 232.478 12.257
13.370 235.534 12.455
13.412 238.591 12.653
13.470 240.891 12.778
13.528 243.191 12.904
13.586 245.492 13.030
13.645 247.792 13.156
13.703 250.092 13.282
13.896 250.710 13.307
14.088 251.329 13.332
14.281 251.947 13.358
14.474 252.565 13.383
14.667 253.184 13.409
14.845 253.888 13.422
15.023 254.593 13.436
15.201 255.297 13.450
15.379 256.002 13.464
15.557 256.706 13.478
15.658 257.286 13.488
15.759 257.866 13.499
15.861 258.445 13.510
15.962 259.025 13.521
16.063 259.605 13.531
16.104 259.940 13.543
16.144 260.276 13.554
16.185 260.612 13.566
16.225 260.947 13.577
16.265 261.283 13.589
6.073 152.760 11.330
6.117 153.609 11.458
6.174 154.888 11.530
6.231 156.166 11.601
6.288 157.445 11.673
6.345 158.724 11.745
6.401 160.002 11.817
6.451 161.606 11.984
6.500 163.210 12.152
6.550 164.814 12.319
6.599 166.418 12.486
6.649 168.022 12.653
6.693 168.948 12.780
6.737 169.874 12.906
6.782 170.800 13.032
6.826 171.726 13.159
6.870 172.653 13.285
6.946 173.200 13.314
7.022 173.748 13.343
7.098 174.295 13.371
7.173 174.843 13.400
7.249 175.391 13.429
7.334 175.611 13.440
7.419 175.831 13.452
7.504 176.051 13.464
7.589 176.271 13.475
7.674 176.491 13.487
7.710 176.612 13.498
7.746 176.732 13.508
7.782 176.853 13.519
7.818 176.974 13.530
7.853 177.095 13.540
7.867 177.463 13.551
7.881 177.830 13.561
7.894 178.198 13.572
7.908 178.566 13.582
7.922 178.933 13.592
6.073 152.760 5.856
6.117 153.609 5.911
6.174 154.888 5.951
6.231 156.166 5.990
6.288 157.445 6.030
6.345 158.724 6.070
6.401 160.002 6.110
6.451 161.606 6.194
6.500 163.210 6.278
6.550 164.814 6.362
6.599 166.418 6.446
6.649 168.022 6.530
6.693 168.948 6.585
6.737 169.874 6.640
6.782 170.800 6.695
6.826 171.726 6.750
6.870 172.653 6.804
6.946 173.200 6.818
7.022 173.748 6.831
7.098 174.295 6.844
7.173 174.843 6.857
7.249 175.391 6.870
7.334 175.611 6.877
7.419 175.831 6.884
7.504 176.051 6.891
7.589 176.271 6.897
7.674 176.491 6.904
7.710 176.612 6.910
7.746 176.732 6.916
7.782 176.853 6.922
7.818 176.974 6.928
7.853 177.095 6.934
7.867 177.463 6.940
7.881 177.830 6.946
7.894 178.198 6.951
7.908 178.566 6.957
7.922 178.933 6.962
4.752 114.974 5.036
4.795 115.563 5.079
4.848 116.847 5.119
4.901 118.131 5.160
4.955 119.415 5.201
5.008 120.699 5.241
5.061 121.983 5.282
5.090 123.498 5.355
5.119 125.012 5.429
5.147 126.526 5.502
5.176 128.040 5.576
5.204 129.554 5.649
5.240 130.345 5.695
5.275 131.136 5.741
5.310 131.928 5.787
5.345 132.719 5.833
5.380 133.510 5.879
5.436 133.899 5.888
5.492 134.287 5.896
5.548 134.676 5.905
5.604 135.064 5.913
5.660 135.453 5.922
5.699 135.633 5.927
5.738 135.814 5.931
5.776 135.995 5.936
5.815 136.176 5.941
5.854 136.356 5.946
5.875 136.581 5.951
5.897 136.806 5.956
5.918 137.031 5.962
5.940 137.256 5.967
5.961 137.482 5.972
5.977 137.680 5.978
5.994 137.879 5.983
6.010 138.078 5.989
6.026 138.277 5.994
6.042 138.476 6.000
61
-------
Alternative Fast-Pass IM240 Standards
Corresponding to Composite Start-up Emission Standards in §85.2205(a)(2)(vi)
Light Duty Truck 3&4
Sec
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
1982-1983
HC CO NOx
1.064 14.776 0.513
1.091 15.338 0.551
1.118 15.900 0.590
1.145 16.462 0.629
1.172 17.023 0.667
1.199 17.585 0.706
1.237 17.834 0.711
1.275 18.084 0.716
1.313 18.333 0.721
1.351 18.582 0.727
1.389 18.832 0.732
1.459 19.867 0.796
1.529 20.902 0.861
1.599 21.937 0.925
1.669 22.972 0.989
1.738 24.008 1.053
1.784 24.572 1.096
1.830 25.136 1.138
1.876 25.701 1.180
1.922 26.265 1.223
1.968 26.830 1.265
2.020 27.642 1.294
2.072 28.454 1.324
2.124 29.266 1.353
2.176 30.079 1.382
2.228 30.891 1.411
2.265 31.485 1.449
2.302 32.078 1.486
2.340 32.672 1.523
2.377 33.266 1.560
2.415 33.860 1.597
2.451 34.487 1.611
2.487 35.113 1.625
2.523 35.740 1.639
2.559 36.367 1.653
2.595 36.994 1.667
2.639 37.728 1.699
2.683 38.462 1.732
2.728 39.197 1.765
1984-1987
HC CO NOx
0.585 10.661 0.513
0.609 11.033 0.551
0.633 11.405 0.590
0.657 11.777 0.629
0.681 12.149 0.667
0.705 12.521 0.706
0.730 12.895 0.711
0.754 13.269 0.716
0.779 13.643 0.721
0.803 14.018 0.727
0.828 14.392 0.732
0.854 15.098 0.796
0.880 15.805 0.861
0.907 16.511 0.925
0.933 17.217 0.989
0.959 17.924 1.053
0.989 18.458 1.096
1.019 18.992 1.138
1.050 19.526 1.180
1.080 20.060 1.223
1.110 20.594 1.265
1.146 21.719 1.294
1.182 22.845 1.324
1.218 23.970 1.353
1.254 25.095 1.382
1.290 26.221 1.411
1.310 26.449 1.449
1.330 26.677 1.486
1.350 26.905 1.523
1.370 27.133 1.560
1.390 27.361 1.597
1.405 27.372 1.611
1.420 27.383 1.625
1.434 27.393 1.639
1.449 27.404 1.653
1.464 27.415 1.667
1.497 28.054 1.699
1.530 28.694 1.732
1.563 29.333 1.765
1988-1990
HC CO NOx
0.585 10.661 0.436
0.609 11.033 0.463
0.633 11.405 0.490
0.657 11.777 0.517
0.681 12.149 0.544
0.705 12.521 0.572
0.730 12.895 0.576
0.754 13.269 0.580
0.779 13.643 0.584
0.803 14.018 0.588
0.828 14.392 0.592
0.854 15.098 0.636
0.880 15.805 0.681
0.907 16.511 0.726
0.933 17.217 0.771
0.959 17.924 0.815
0.989 18.458 0.840
1.019 18.992 0.866
1.050 19.526 0.891
1.080 20.060 0.916
1.110 20.594 0.941
1.146 21.719 0.978
1.182 22.845 1.016
1.218 23.970 1.053
1.254 25.095 1.090
1.290 26.221 1.128
1.310 26.449 1.160
1.330 26.677 1.192
1.350 26.905 1.224
1.370 27.133 1.256
1.390 27.361 1.288
1.405 27.372 1.301
1.420 27.383 1.313
1.434 27.393 1.326
1.449 27.404 1.338
1.464 27.415 1.351
1.497 28.054 1.366
1.530 28.694 1.382
1.563 29.333 1.397
1991
HC CO NOx
0.477 5.069 0.395
0.494 5.129 0.420
0.512 5.189 0.445
0.529 5.249 0.470
0.547 5.309 0.495
0.564 5.369 0.520
0.582 5.562 0.524
0.601 5.755 0.527
0.619 5.948 0.531
0.637 6.142 0.535
0.656 6.335 0.539
0.681 6.890 0.578
0.707 7.445 0.617
0.732 7.999 0.657
0.758 8.554 0.696
0.783 9.109 0.735
0.799 9.593 0.760
0.816 10.076 0.785
0.832 10.560 0.810
0.848 11.044 0.835
0.864 11.527 0.860
0.891 12.038 0.893
0.917 12.549 0.926
0.943 13.059 0.959
0.969 13.570 0.992
0.995 14.081 1.026
1.015 14.438 1.051
1.035 14.796 1.077
1.055 15.154 1.103
1.075 15.512 1.129
1.095 15.870 1.155
1.109 16.268 1.166
1.124 16.667 1.177
1.138 17.066 1.188
1.153 17.465 1.200
1.167 17.863 1.211
1.182 18.249 1.230
1.196 18.635 1.250
1.211 19.020 1.269
62
-------
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
2.772 39.931 1.797
2.817 40.666 1.830
2.859 41.083 1.854
2.901 41.500 1.878
2.943 41.918 1.902
2.985 42.335 1.925
3.027 42.753 1.949
3.061 43.705 1.977
3.096 44.657 2.005
3.130 45.609 2.033
3.165 46.562 2.061
3.200 47.514 2.089
3.237 47.873 2.111
3.275 48.233 2.132
3.313 48.592 2.154
3.351 48.952 2.175
3.389 49.311 2.197
3.432 49.503 2.200
3.475 49.694 2.203
3.518 49.886 2.206
3.562 50.077 2.209
3.605 50.269 2.212
3.645 50.447 2.213
3.686 50.626 2.214
3.727 50.805 2.215
3.767 50.984 2.216
3.808 51.162 2.217
3.853 51.779 2.227
3.898 52.395 2.236
3.943 53.012 2.245
3.988 53.628 2.254
4.033 54.245 2.263
4.081 55.131 2.342
4.128 56.016 2.420
4.175 56.902 2.498
4.223 57.788 2.576
4.270 58.674 2.654
4.300 59.222 2.740
4.331 59.771 2.826
4.361 60.319 2.912
4.391 60.868 2.998
4.421 61.416 3.084
4.449 61.935 3.101
4.476 62.455 3.118
4.503 62.974 3.136
1.596 29.972 1.797
1.629 30.612 1.830
1.650 31.097 1.854
1.672 31.583 1.878
1.694 32.068 1.902
1.715 32.554 1.925
1.737 33.039 1.949
1.760 33.193 1.977
1.782 33.347 2.005
1.805 33.501 2.033
1.828 33.655 2.061
1.851 33.809 2.089
1.872 34.035 2.111
1.894 34.261 2.132
1.915 34.488 2.154
1.937 34.714 2.175
1.958 34.941 2.197
1.973 35.115 2.200
1.988 35.289 2.203
2.002 35.463 2.206
2.017 35.637 2.209
2.032 35.811 2.212
2.044 35.968 2.213
2.056 36.125 2.214
2.068 36.282 2.215
2.081 36.440 2.216
2.093 36.597 2.217
2.111 36.968 2.227
2.129 37.339 2.236
2.147 37.710 2.245
2.165 38.081 2.254
2.183 38.453 2.263
2.221 40.429 2.342
2.258 42.405 2.420
2.295 44.382 2.498
2.333 46.358 2.576
2.370 48.335 2.654
2.404 49.060 2.740
2.437 49.785 2.826
2.471 50.511 2.912
2.504 51.236 2.998
2.538 51.962 3.084
2.560 52.113 3.101
2.582 52.265 3.118
2.604 52.417 3.136
1.596 29.972 1.412
1.629 30.612 1.427
1.650 31.097 1.443
1.672 31.583 1.459
1.694 32.068 1.475
1.715 32.554 1.491
1.737 33.039 1.507
1.760 33.193 1.528
1.782 33.347 1.550
1.805 33.501 1.571
1.828 33.655 1.593
1.851 33.809 1.615
1.872 34.035 1.623
1.894 34.261 1.632
1.915 34.488 1.640
1.937 34.714 1.648
1.958 34.941 1.657
1.973 35.115 1.659
1.988 35.289 1.661
2.002 35.463 1.663
2.017 35.637 1.665
2.032 35.811 1.667
2.044 35.968 1.668
2.056 36.125 1.669
2.068 36.282 1.671
2.081 36.440 1.672
2.093 36.597 1.674
2.111 36.968 1.680
2.129 37.339 1.686
2.147 37.710 1.692
2.165 38.081 1.698
2.183 38.453 1.704
2.221 40.429 1.779
2.258 42.405 1.854
2.295 44.382 1.928
2.333 46.358 2.003
2.370 48.335 2.078
2.404 49.060 2.132
2.437 49.785 2.187
2.471 50.511 2.241
2.504 51.236 2.296
2.538 51.962 2.350
2.560 52.113 2.365
2.582 52.265 2.381
2.604 52.417 2.396
1.225 19.406 1.289
1.239 19.792 1.308
1.255 19.906 1.321
1.271 20.020 1.334
1.287 20.134 1.347
1.303 20.248 1.361
1.318 20.362 1.374
1.331 20.782 1.391
1.344 21.202 1.409
1.357 21.623 1.426
1.370 22.043 1.444
1.382 22.463 1.461
1.407 22.571 1.475
1.431 22.678 1.489
1.455 22.786 1.503
1.480 22.894 1.517
1.504 23.001 1.531
1.531 23.112 1.531
1.558 23.223 1.532
1.586 23.334 1.533
1.613 23.445 1.533
1.640 23.556 1.534
1.654 23.558 1.534
1.668 23.560 1.534
1.682 23.562 1.535
1.696 23.564 1.535
1.710 23.567 1.535
1.727 23.924 1.547
1.744 24.282 1.558
1.762 24.639 1.570
1.779 24.997 1.581
1.796 25.355 1.593
1.819 25.871 1.636
1.842 26.387 1.678
1.865 26.903 1.721
1.887 27.419 1.764
1.910 27.935 1.807
1.936 28.221 1.864
1.962 28.506 1.921
1.988 28.792 1.978
2.014 29.077 2.035
2.040 29.363 2.092
2.057 29.405 2.107
2.074 29.447 2.121
2.090 29.489 2.135
63
-------
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
4.531 63.493 3.153
4.558 64.013 3.170
4.600 64.559 3.173
4.642 65.105 3.175
4.684 65.651 3.178
4.726 66.197 3.181
4.768 66.743 3.184
4.804 67.600 3.206
4.840 68.458 3.229
4.876 69.315 3.251
4.911 70.173 3.274
4.947 71.030 3.296
4.983 71.729 3.310
5.019 72.427 3.323
5.055 73.126 3.337
5.091 73.825 3.350
5.126 74.523 3.364
5.178 75.331 3.370
5.230 76.139 3.376
5.282 76.947 3.382
5.334 77.755 3.388
5.386 78.563 3.394
5.468 79.372 3.432
5.549 80.181 3.469
5.630 80.990 3.507
5.712 81.798 3.544
5.793 82.607 3.582
5.825 83.486 3.639
5.856 84.365 3.697
5.888 85.245 3.754
5.920 86.124 3.811
5.951 87.003 3.869
5.975 87.915 3.892
5.998 88.827 3.916
6.022 89.739 3.939
6.046 90.652 3.963
6.069 91.564 3.986
6.099 92.475 4.000
6.129 93.387 4.014
6.159 94.298 4.029
6.189 95.209 4.043
6.219 96.121 4.057
6.313 97.599 4.117
6.407 99.077 4.176
6.501 100.555 4.236
2.625 52.569 3.153
2.647 52.721 3.170
2.673 52.723 3.173
2.698 52.724 3.175
2.723 52.726 3.178
2.749 52.728 3.181
2.774 52.729 3.184
2.799 53.168 3.206
2.824 53.606 3.229
2.850 54.044 3.251
2.875 54.483 3.274
2.900 54.921 3.296
2.920 55.078 3.310
2.941 55.236 3.323
2.961 55.393 3.337
2.981 55.551 3.350
3.001 55.708 3.364
3.027 55.921 3.370
3.052 56.134 3.376
3.078 56.346 3.382
3.103 56.559 3.388
3.129 56.771 3.394
3.167 57.854 3.432
3.206 58.937 3.469
3.244 60.020 3.507
3.283 61.102 3.544
3.322 62.185 3.582
3.342 62.366 3.639
3.363 62.548 3.697
3.383 62.729 3.754
3.404 62.910 3.811
3.425 63.091 3.869
3.453 63.539 3.892
3.482 63.987 3.916
3.510 64.435 3.939
3.539 64.883 3.963
3.568 65.331 3.986
3.595 65.704 4.000
3.623 66.077 4.014
3.650 66.450 4.029
3.677 66.823 4.043
3.705 67.197 4.057
3.767 69.206 4.117
3.829 71.215 4.176
3.891 73.225 4.236
2.625 52.569 2.411
2.647 52.721 2.426
2.673 52.723 2.430
2.698 52.724 2.433
2.723 52.726 2.437
2.749 52.728 2.441
2.774 52.729 2.445
2.799 53.168 2.467
2.824 53.606 2.489
2.850 54.044 2.512
2.875 54.483 2.534
2.900 54.921 2.557
2.920 55.078 2.569
2.941 55.236 2.580
2.961 55.393 2.592
2.981 55.551 2.604
3.001 55.708 2.616
3.027 55.921 2.619
3.052 56.134 2.623
3.078 56.346 2.627
3.103 56.559 2.630
3.129 56.771 2.634
3.167 57.854 2.672
3.206 58.937 2.711
3.244 60.020 2.749
3.283 61.102 2.787
3.322 62.185 2.826
3.342 62.366 2.851
3.363 62.548 2.875
3.383 62.729 2.900
3.404 62.910 2.925
3.425 63.091 2.949
3.453 63.539 2.959
3.482 63.987 2.968
3.510 64.435 2.978
3.539 64.883 2.987
3.568 65.331 2.997
3.595 65.704 3.007
3.623 66.077 3.017
3.650 66.450 3.028
3.677 66.823 3.038
3.705 67.197 3.049
3.767 69.206 3.113
3.829 71.215 3.178
3.891 73.225 3.242
2.107 29.531 2.149
2.124 29.573 2.163
2.152 29.865 2.166
2.179 30.157 2.169
2.207 30.449 2.173
2.234 30.741 2.176
2.262 31.033 2.179
2.276 31.230 2.200
2.290 31.428 2.222
2.304 31.625 2.243
2.318 31.823 2.265
2.332 32.020 2.286
2.355 32.099 2.297
2.377 32.178 2.307
2.399 32.256 2.318
2.422 32.335 2.329
2.444 32.413 2.339
2.464 32.638 2.343
2.485 32.862 2.347
2.505 33.086 2.350
2.525 33.310 2.354
2.545 33.534 2.358
2.573 34.147 2.395
2.600 34.760 2.431
2.628 35.373 2.468
2.655 35.985 2.505
2.682 36.598 2.542
2.702 36.880 2.574
2.722 37.162 2.606
2.742 37.444 2.638
2.762 37.727 2.671
2.782 38.009 2.703
2.797 38.632 2.715
2.811 39.255 2.726
2.825 39.878 2.738
2.839 40.501 2.750
2.853 41.124 2.762
2.868 41.450 2.774
2.883 41.776 2.786
2.898 42.102 2.799
2.913 42.428 2.811
2.927 42.754 2.823
2.969 44.233 2.870
3.011 45.712 2.917
3.053 47.191 2.964
64
-------
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
6.595 102.033 4.295
6.689 103.511 4.355
7.010 107.552 4.551
7.331 111.593 4.747
7.652 115.634 4.943
7.972 119.676 5.139
8.293 123.717 5.335
8.671 125.252 5.516
9.050 126.786 5.696
9.428 128.321 5.876
9.806 129.855 6.056
10.184 131.390 6.237
10.426 132.095 6.345
10.667132.801 6.452
10.909 133.506 6.560
11.150134.211 6.668
11.392 134.917 6.776
11.439 137.703 6.910
11.486 140.490 7.045
11.533 143.276 7.179
11.581 146.063 7.313
11.628 148.849 7.447
11.671 154.282 7.621
11.715159.715 7.795
11.759 165.147 7.969
11.803 170.580 8.143
11.846 176.013 8.318
11.887179.970 8.499
11.928 183.927 8.681
11.969 187.884 8.862
12.010191.841 9.043
12.051 195.798 9.225
12.090 197.691 9.386
12.128 199.584 9.547
12.166201.476 9.708
12.205203.369 9.869
12.243 205.262 10.030
12.281 208.341 10.188
12.319 211.419 10.346
12.357 214.498 10.504
12.395 217.577 10.662
12.433 220.656 10.820
12.509 221.810 10.948
12.585 222.965 11.075
12.661 224.119 11.203
3.953 75.234 4.295
4.015 77.243 4.355
4.078 79.985 4.551
4.142 82.727 4.747
4.205 85.469 4.943
4.268 88.211 5.139
4.332 90.953 5.335
4.380 93.266 5.516
4.428 95.579 5.696
4.477 97.892 5.876
4.525 100.205 6.056
4.573 102.517 6.237
4.618 103.813 6.345
4.664 105.109 6.452
4.709 106.404 6.560
4.754 107.700 6.668
4.799 108.995 6.776
4.858 110.733 6.910
4.917 112.471 7.045
4.977 114.209 7.179
5.036 115.946 7.313
5.095 117.684 7.447
5.158 119.775 7.621
5.221 121.866 7.795
5.284 123.956 7.969
5.347126.047 8.143
5.411 128.138 8.318
5.428 129.673 8.499
5.446 131.209 8.681
5.463 132.745 8.862
5.481 134.281 9.043
5.499 135.816 9.225
5.561 137.198 9.386
5.623 138.580 9.547
5.686 139.961 9.708
5.748 141.343 9.869
5.810 142.724 10.030
5.828 144.052 10.188
5.845 145.381 10.346
5.863 146.709 10.504
5.880 148.037 10.662
5.898 149.365 10.820
5.942 150.214 10.948
5.986 151.063 11.075
6.029 151.912 11.203
3.953 75.234 3.307
4.015 77.243 3.371
4.078 79.985 3.503
4.142 82.727 3.635
4.205 85.469 3.767
4.268 88.211 3.899
4.332 90.953 4.030
4.380 93.266 4.145
4.428 95.579 4.260
4.477 97.892 4.375
4.525 100.205 4.490
4.573 102.517 4.605
4.618 103.813 4.673
4.664 105.109 4.741
4.709 106.404 4.808
4.754 107.700 4.876
4.799 108.995 4.944
4.858 110.733 5.057
4.917 112.471 5.171
4.977 114.209 5.284
5.036 115.946 5.398
5.095 117.684 5.511
5.158 119.775 5.641
5.221 121.866 5.770
5.284 123.956 5.900
5.347 126.047 6.029
5.411 128.138 6.159
5.428 129.673 6.285
5.446 131.209 6.411
5.463 132.745 6.537
5.481 134.281 6.663
5.499 135.816 6.789
5.561 137.198 6.875
5.623 138.580 6.961
5.686 139.961 7.047
5.748 141.343 7.133
5.810 142.724 7.219
5.828 144.052 7.346
5.845 145.381 7.473
5.863 146.709 7.600
5.880 148.037 7.727
5.898 149.365 7.853
5.942 150.214 7.929
5.986 151.063 8.005
6.029 151.912 8.080
3.095 48.670 3.011
3.136 50.149 3.057
3.182 51.569 3.181
3.227 52.988 3.306
3.272 54.408 3.430
3.318 55.828 3.554
3.363 57.247 3.678
3.410 58.958 3.796
3.458 60.670 3.914
3.505 62.381 4.033
3.552 64.092 4.151
3.600 65.804 4.269
3.644 66.939 4.322
3.688 68.075 4.374
3.732 69.210 4.426
3.776 70.345 4.479
3.821 71.481 4.531
3.856 73.077 4.626
3.891 74.674 4.722
3.927 76.271 4.817
3.962 77.867 4.912
3.997 79.464 5.008
4.024 81.282 5.111
4.050 83.100 5.214
4.077 84.919 5.318
4.104 86.737 5.421
4.131 88.555 5.524
4.154 90.333 5.656
4.178 92.110 5.787
4.202 93.888 5.919
4.225 95.665 6.050
4.249 97.442 6.182
4.285 98.856 6.266
4.321 100.271 6.350
4.357 101.685 6.435
4.393 103.099 6.519
4.430 104.513 6.603
4.460 106.134 6.706
4.490 107.755 6.810
4.520 109.376 6.913
4.550 110.997 7.017
4.580 112.617 7.120
4.623 113.207 7.195
4.666 113.796 7.270
4.709 114.385 7.345
65
-------
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
12.738 225.274 11.330
12.814 226.429 11.458
12.891 228.364 11.530
12.969 230.299 11.601
13.046 232.235 11.673
13.124 234.170 11.745
13.201 236.105 11.817
13.233 239.385 11.984
13.264 242.664 12.152
13.296 245.943 12.319
13.328 249.223 12.486
13.359 252.502 12.653
13.423 253.243 12.780
13.487 253.983 12.906
13.551 254.724 13.032
13.615 255.464 13.159
13.679 256.204 13.285
13.852 256.417 13.314
14.025 256.629 13.343
14.198 256.841 13.371
14.371 257.053 13.400
14.544 257.265 13.429
14.737 257.645 13.440
14.929 258.025 13.452
15.122 258.405 13.464
15.315 258.785 13.475
15.507 259.165 13.487
15.616 259.629 13.498
15.725 260.092 13.508
15.834 260.556 13.519
15.944 261.020 13.530
16.053 261.484 13.540
16.085 261.890 13.551
16.117 262.296 13.561
16.149 262.701 13.572
16.181 263.107 13.582
16.214 263.513 13.592
6.073 152.760 11.330
6.117 153.609 11.458
6.174 154.888 11.530
6.231 156.166 11.601
6.288 157.445 11.673
6.345 158.724 11.745
6.401 160.002 11.817
6.451 161.606 11.984
6.500 163.210 12.152
6.550 164.814 12.319
6.599 166.418 12.486
6.649 168.022 12.653
6.693 168.948 12.780
6.737169.874 12.906
6.782 170.800 13.032
6.826 171.726 13.159
6.870 172.653 13.285
6.946 173.200 13.314
7.022 173.748 13.343
7.098 174.295 13.371
7.173 174.843 13.400
7.249 175.391 13.429
7.334 175.611 13.440
7.419 175.831 13.452
7.504 176.051 13.464
7.589 176.271 13.475
7.674 176.491 13.487
7.710 176.612 13.498
7.746 176.732 13.508
7.782 176.853 13.519
7.818 176.974 13.530
7.853 177.095 13.540
7.867 177.463 13.551
7.881 177.830 13.561
7.894 178.198 13.572
7.908 178.566 13.582
7.922 178.933 13.592
6.073 152.760 8.156
6.117 153.609 8.232
6.174 154.888 8.295
6.231 156.166 8.357
6.288 157.445 8.420
6.345 158.724 8.483
6.401 160.002 8.545
6.451 161.606 8.670
6.500 163.210 8.794
6.550 164.814 8.919
6.599 166.418 9.043
6.649 168.022 9.168
6.693 168.948 9.251
6.737 169.874 9.334
6.782 170.800 9.417
6.826 171.726 9.500
6.870 172.653 9.584
6.946 173.200 9.598
7.022 173.748 9.612
7.098 174.295 9.627
7.173 174.843 9.641
7.249 175.391 9.655
7.334 175.611 9.664
7.419 175.831 9.674
7.504 176.051 9.683
7.589 176.271 9.692
7.674 176.491 9.701
7.710 176.612 9.710
7.746 176.732 9.719
7.782 176.853 9.728
7.818 176.974 9.737
7.853 177.095 9.746
7.867 177.463 9.754
7.881 177.830 9.761
7.894 178.198 9.769
7.908 178.566 9.777
7.922 178.933 9.785
4.752 114.974 7.419
4.795 115.563 7.494
4.848 116.847 7.544
4.901 118.131 7.594
4.955 119.415 7.644
5.008 120.699 7.694
5.061 121.983 7.744
5.090 123.498 7.846
5.119 125.012 7.948
5.147 126.526 8.051
5.176 128.040 8.153
5.204 129.554 8.255
5.240 130.345 8.328
5.275 131.136 8.400
5.310 131.928 8.472
5.345 132.719 8.545
5.380 133.510 8.617
5.436 133.899 8.630
5.492 134.287 8.642
5.548 134.676 8.655
5.604 135.064 8.667
5.660 135.453 8.680
5.699 135.633 8.688
5.738 135.814 8.696
5.776 135.995 8.704
5.815 136.176 8.712
5.854 136.356 8.720
5.875 136.581 8.727
5.897 136.806 8.733
5.918 137.031 8.740
5.940 137.256 8.746
5.961 137.482 8.753
5.977 137.680 8.760
5.994 137.879 8.767
6.010 138.078 8.774
6.026 138.277 8.781
6.042 138.476 8.788
66
-------
Appendix C
Fast Pass IM240 Standards Developed for Wisconsin
67
-------
Fast Pass IM240 Standards Developed for Wisconsin
Wisconsin requested EPA provide fast-pass outpoints for final and intermediate standards. A method is outlined below.
This was applied only to the Appendix. A fast-pass outpoints but could be used on others also.
1) A scale factor for each pollutant at each second is defined. This was done to calculate the cutpoint at second i
for each pollutant at each standard.
For example: HC Scale Factor for the 0.8 cutpoint
FPHC Scale Factor = [HC(0.8)Fast Pass Cutpoint at t= i ] / [HC(0.8) Fast Pass Cutpoint
att=239]
2) The ratio of the Fast Pass cutpoint at t=239 to the distance traveled (1.973 mi) was found. This was done so the
new fast-pass cut points could be scaled to the new full 240 second standard
ForHC(0.8g/mi):
FPHC 239= 1.615 g
Distance = 1.973 mi
FPHC 239 g/mi = 0.81855
% above 0.8 g/mi standard = (0.818-0.8)70.8*100 = 2.2%
For new HC standard (0.6 g/mi):
(FPHC 239 g/mi - 0.6)/0.6 * 100 = 2.2%
(This provides the same 2.2% overshoot as the phase-in fast-pass standards.)
FPHC 239 g/mi = 0.6132g/mi
FPHC 239 g= 1.2098
3) The new fast pass standards will then be calculated as:
HC(0.6)FP = FP(0.6)239 * HCSF(0.8)i
t HC(0.8) g FPHC SF HC(0.6) g
30 0.124 0.0768 0.0929
68
-------
31 0.126 0.0780 0.0944
238 1.614 0.9994 1.2091
239 1.615 1.0000 1.2098
4) For Phase 2 cut points, where needed:
Take the old standard, for example, FPHC Phase 2 = 0.5 g/mi
The distance traveled from second 108 to second 239 is 1.359 mi
The old FPHC 239 cutpoint is 0.716 g
In terms of g/mi this is 0.716/1.359 = 0.527 g/mi
The delta between this value and the actual standard is: (0.527-0.5) = 0.027 g/mi
The new FPHC 239 g/mi cutpoint is: 0.4 + 0.027 = 0.427 g/mi. In terms of g, this is FPHC 239
g/mi* 1.359 mi = 0.580 g
The Scale Factor is calculated as before for each second of the test, and the Phase 2 cutpoint at
each second is calculated by multiplying this Scale Factor times the new FP cutpoint in g at 239.
In this case, that new FP cutpoint would be 0.580 * Scale Factor for each second.
69
-------
Sec
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
Hydrocarbon(g)
Composite Phase 2 Composite Phase 2 Composite Phase 2
(0.6) (0.4) (0.8) (0.5) (1.1) (0.7)
0.093 n/a 0.124 n/a 0.226 n/a
0.095 n/a 0.126 n/a 0.232 n/a
0.097 n/a 0.129 n/a 0.237 n/a
0.101 n/a 0.135 n/a 0.241 n/a
0.105 n/a 0.140 n/a 0.246 n/a
0.110 n/a 0.146 n/a 0.254 n/a
0.113 n/a 0.150 n/a 0.259 n/a
0.115 n/a 0.153 n/a 0.269 n/a
0.117 n/a 0.156 n/a 0.272 n/a
0.120 n/a 0.160 n/a 0.273 n/a
0.124 n/a 0.165 n/a 0.287 n/a
0.127 n/a 0.169 n/a 0.293 n/a
0.129 n/a 0.172 n/a 0.300 n/a
0.130 n/a 0.173 n/a 0.314 n/a
0.133 n/a 0.177 n/a 0.330 n/a
0.148 n/a 0.197 n/a 0.345 n/a
0.150 n/a 0.200 n/a 0.357 n/a
0.156 n/a 0.208 n/a 0.374 n/a
0.166 n/a 0.221 n/a 0.388 n/a
0.174 n/a 0.232 n/a 0.398 n/a
0.176 n/a 0.235 n/a 0.407 n/a
0.179 n/a 0.238 n/a 0.416 n/a
0.180 n/a 0.240 n/a 0.426 n/a
0.182 n/a 0.242 n/a 0.433 n/a
0.185 n/a 0.246 n/a 0.438 n/a
0.187 n/a 0.249 n/a 0.445 n/a
0.189 n/a 0.252 n/a 0.452 n/a
0.196 n/a 0.261 n/a 0.458 n/a
0.203 n/a 0.271 n/a 0.463 n/a
0.207 n/a 0.276 n/a 0.471 n/a
0.209 n/a 0.278 n/a 0.492 n/a
0.210 n/a 0.280 n/a 0.495 n/a
0.212 n/a 0.282 n/a 0.498 n/a
0.212 n/a 0.283 n/a 0.501 n/a
0.213 n/a 0.284 n/a 0.505 n/a
0.214 n/a 0.285 n/a 0.512 n/a
0.215 n/a 0.286 n/a 0.520 n/a
0.216 n/a 0.288 n/a 0.527 n/a
0.218 n/a 0.291 n/a 0.539 n/a
0.221 n/a 0.294 n/a 0.545 n/a
0.222 n/a 0.296 n/a 0.551 n/a
0.224 n/a 0.298 n/a 0.556 n/a
0.225 n/a 0.300 n/a 0.559 n/a
0.227 n/a 0.302 n/a 0.566 n/a
0.228 n/a 0.304 n/a 0.578 n/a
0.230 n/a 0.307 n/a 0.589 n/a
0.231 n/a 0.308 n/a 0.597 n/a
0.231 n/a 0.308 n/a 0.604 n/a
Carbon Monoxide (g)
Composite Phase 2 Composite Phase 2 Composite Phase 2
(10.0) (0.8) (15.0) (12.0) (20.0) (16.0)
0.462 n/a 0.693 n/a 1.502 n/a
0.515 n/a 0.773 n/a 1.546 n/a
0.558 n/a 0.837 n/a 1.568 n/a
0.567 n/a 0.851 n/a 1.582 n/a
0.569 n/a 0.853 n/a 1.593 n/a
0.571 n/a 0.857 n/a 1.602 n/a
0.600 n/a 0.900 n/a 1.621 n/a
0.640 n/a 0.960 n/a 1.631 n/a
0.689 n/a 1.034 n/a 1.702 n/a
0.713 n/a 1.070 n/a 1.784 n/a
0.717 n/a 1.076 n/a 1.879 n/a
0.722 n/a 1.083 n/a 2.162 n/a
0.735 n/a 1.102 n/a 2.307 n/a
0.741 n/a 1.111 n/a 2.343 n/a
0.743 n/a 1.114 n/a 2.376 n/a
0.771 n/a 1.157 n/a 2.406 n/a
0.896 n/a 1.344 n/a 2.433 n/a
0.988 n/a 1.482 n/a 2.458 n/a
1.020 n/a 1.530 n/a 2.483 n/a
1.028 n/a 1.542 n/a 2.774 n/a
1.035 n/a 1.553 n/a 2.844 n/a
1.047 n/a 1.571 n/a 2.900 n/a
1.063 n/a 1.595 n/a 2.936 n/a
1.089 n/a 1.633 n/a 3.133 n/a
1.123 n/a 1.685 n/a 3.304 n/a
1.126 n/a 1.689 n/a 3.407 n/a
1.129 n/a 1.693 n/a 3.456 n/a
1.133 n/a 1.700 n/a 3.480 n/a
1.149 n/a 1.723 n/a 3.518 n/a
1.235 n/a 1.852 n/a 3.560 n/a
1.248 n/a 1.872 n/a 3.593 n/a
1.248 n/a 1.872 n/a 3.628 n/a
1.248 n/a 1.872 n/a 3.641 n/a
1.267 n/a 1.900 n/a 3.655 n/a
1.278 n/a 1.917 n/a 3.680 n/a
1.296 n/a 1.944 n/a 3.700 n/a
1.333 n/a 2.000 n/a 3.728 n/a
1.373 n/a 2.060 n/a 3.857 n/a
1.376 n/a 2.064 n/a 3.894 n/a
1.384 n/a 2.076 n/a 3.943 n/a
1.403 n/a 2.104 n/a 3.983 n/a
1.411 n/a 2.117 n/a 4.009 n/a
1.417 n/a 2.125 n/a 4.023 n/a
1.420 n/a 2.130 n/a 4.023 n/a
1.425 n/a 2.138 n/a 4.053 n/a
1.435 n/a 2.152 n/a 4.063 n/a
1.447 n/a 2.170 n/a 4.077 n/a
1.459 n/a 2.188 n/a 4.225 n/a
Oxides of Nitrogen (g)
Composit Composite Composite
e
(1.5) (2.0) (2.5)
0.125 0.167 0.262
0.133 0.177 0.275
0.141 0.188 0.301
0.161 0.214 0.317
0.174 0.232 0.327
0.180 0.240 0.330
0.182 0.243 0.332
0.184 0.245 0.334
0.185 0.246 0.336
0.185 0.246 0.337
0.188 0.250 0.354
0.195 0.260 0.366
0.208 0.277 0.410
0.233 0.311 0.414
0.246 0.328 0.438
0.257 0.343 0.477
0.269 0.359 0.506
0.280 0.373 0.518
0.287 0.383 0.522
0.289 0.385 0.526
0.300 0.400 0.554
0.308 0.410 0.574
0.326 0.434 0.587
0.348 0.464 0.601
0.354 0.472 0.615
0.360 0.480 0.629
0.368 0.491 0.643
0.375 0.500 0.667
0.380 0.506 0.678
0.382 0.509 0.683
0.384 0.512 0.686
0.387 0.516 0.693
0.389 0.519 0.699
0.392 0.523 0.703
0.397 0.529 0.707
0.400 0.533 0.711
0.401 0.535 0.716
0.405 0.540 0.721
0.413 0.551 0.726
0.422 0.563 0.742
0.431 0.575 0.759
0.441 0.588 0.773
0.450 0.600 0.784
0.452 0.603 0.790
0.453 0.604 0.794
0.460 0.613 0.799
0.468 0.624 0.809
0.485 0.646 0.821
70
-------
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
0.231 n/a
0.236 n/a
0.240 n/a
0.243 n/a
0.245 n/a
0.247 n/a
0.250 n/a
0.252 n/a
0.254 n/a
0.257 n/a
0.260 n/a
0.263 n/a
0.267 n/a
0.269 n/a
0.270 n/a
0.272 n/a
0.275 n/a
0.278 n/a
0.279 n/a
0.282 n/a
0.291 n/a
0.297 n/a
0.304 n/a
0.308 n/a
0.308 n/a
0.309 n/a
0.310 n/a
0.316 n/a
0.321 n/a
0.323 n/a
0.341 n/a
0.344 0.012
0.347 0.014
0.348 0.017
0.350 0.019
0.351 0.019
0.353 0.020
0.366 0.021
0.385 0.023
0.404 0.026
0.421 0.028
0.433 0.028
0.435 0.029
0.440 0.031
0.446 0.032
0.452 0.033
0.458 0.034
0.461 0.034
0.468 0.034
0.471 0.036
0.474 0.037
0.478 0.037
0.481 0.040
0.308
0.314
0.320
0.324
0.327
0.329
0.333
0.336
0.339
0.343
0.347
0.350
0.356
0.358
0.360
0.363
0.367
0.370
0.372
0.376
0.388
0.396
0.405
0.410
0.411
0.412
0.413
0.421
0.428
0.430
0.455
0.459
0.462
0.464
0.466
0.468
0.471
0.488
0.513
0.538
0.561
0.577
0.580
0.586
0.594
0.603
0.610
0.615
0.624
0.628
0.632
0.637
0.641
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
0.015
0.017
0.021
0.024
0.024
0.025
0.026
0.029
0.032
0.035
0.035
0.036
0.038
0.040
0.041
0.042
0.042
0.042
0.045
0.046
0.046
0.049
0.611 n/a
0.620 n/a
0.624 n/a
0.628 n/a
0.632 n/a
0.636 n/a
0.642 n/a
0.646 n/a
0.650 n/a
0.654 n/a
0.657 n/a
0.661 n/a
0.664 n/a
0.666 n/a
0.668 n/a
0.670 n/a
0.673 n/a
0.678 n/a
0.686 n/a
0.696 n/a
0.707 n/a
0.718 n/a
0.727 n/a
0.743 n/a
0.754 n/a
0.766 n/a
0.782 n/a
0.798 n/a
0.813 n/a
0.824 n/a
0.853 n/a
0.868 0.037
0.877 0.044
0.885 0.049
0.890 0.052
0.896 0.057
0.901 0.060
0.919 0.067
0.944 0.076
0.954 0.077
0.963 0.078
0.964 0.086
0.967 0.088
0.973 0.091
0.982 0.094
0.991 0.096
1.000 0.099
1.010 0.101
1.018 0.103
1.023 0.105
1.028 0.107
1.031 0.109
1.034 0.111
1.467
1.475
1.475
1.481
1.481
1.485
1.491
1.495
1.508
1.514
1.523
1.533
1.539
1.551
1.553
1.554
1.563
1.565
1.570
1.597
1.634
1.672
1.727
1.773
1.833
1.942
2.108
2.113
2.131
2.192
2.279
2.391
2.397
2.427
2.493
2.579
2.585
2.623
2.677
2.707
2.709
2.719
2.760
2.790
2.799
2.803
2.808
2.821
2.865
2.896
2.907
2.911
2.913
n/a 2.200
n/a 2.212
n/a 2.212
n/a 2.221
n/a 2.222
n/a 2.227
n/a 2.236
n/a 2.243
n/a 2.262
n/a 2.271
n/a 2.284
n/a 2.299
n/a 2.308
n/a 2.326
n/a 2.330
n/a 2.331
n/a 2.344
n/a 2.347
n/a 2.355
n/a 2.395
n/a 2.451
n/a 2.508
n/a 2.590
n/a 2.660
n/a 2.749
n/a 2.913
n/a 3.162
n/a 3.170
n/a 3.197
n/a 3.288
n/a 3.419
0.115 3.587
0.119 3.595
0.163 3.640
0.183 3.740
0.192 3.868
0.200 3.877
0.216 3.934
0.227 4.015
0.237 4.061
0.240 4.063
0.245 4.079
0.252 4.140
0.267 4.185
0.280 4.199
0.318 4.205
0.330 4.212
0.348 4.232
0.356 4.298
0.359 4.344
0.361 4.361
0.363 4.366
0.364 4.369
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
0.168
0.173
0.237
0.266
0.280
0.291
0.314
0.331
0.345
0.350
0.356
0.367
0.388
0.407
0.463
0.480
0.506
0.518
0.522
0.525
0.528
0.530
4.243 n/a
4.260 n/a
4.282 n/a
4.322 n/a
4.398 n/a
4.482 n/a
4.515 n/a
4.518 n/a
4.520 n/a
4.522 n/a
4.522 n/a
4.523 n/a
4.526 n/a
4.527 n/a
4.527 n/a
4.528 n/a
4.528 n/a
4.528 n/a
4.529 n/a
4.575 n/a
4.703 n/a
4.805 n/a
4.886 n/a
4.957 n/a
5.104 n/a
5.340 n/a
5.496 n/a
5.625 n/a
5.815 n/a
6.473 n/a
7.037 n/a
7.419 0.246
7.643 0.257
7.759 0.286
7.824 0.379
7.889 0.425
7.960 0.457
8.024 0.477
8.076 0.494
8.111 0.504
8.130 0.512
8.148 0.519
8.211 0.529
8.478 0.529
8.548 0.530
8.561 0.531
8.568 0.532
8.572 0.533
8.584 0.548
8.592 0.610
8.596 0.614
8.597 0.622
8.601 0.631
0.488
0.494
0.505
0.522
0.530
0.536
0.543
0.553
0.560
0.561
0.561
0.561
0.561
0.561
0.561
0.561
0.561
0.561
0.561
0.561
0.561
0.563
0.573
0.592
0.617
0.650
0.679
0.694
0.716
0.739
0.745
0.746
0.747
0.758
0.771
0.776
0.783
0.794
0.806
0.810
0.810
0.811
0.818
0.822
0.833
0.842
0.851
0.854
0.854
0.854
0.854
0.854
0.854
0.651
0.659
0.673
0.696
0.706
0.715
0.724
0.737
0.747
0.748
0.748
0.748
0.748
0.748
0.748
0.748
0.748
0.748
0.748
0.748
0.748
0.751
0.764
0.789
0.822
0.867
0.905
0.925
0.955
0.985
0.993
0.995
0.996
1.010
1.028
1.034
1.044
1.059
1.075
1.080
1.080
1.081
1.091
1.096
1.111
1.122
1.135
1.138
1.139
1.139
1.139
1.139
1.139
0.833
0.839
0.844
0.857
0.870
0.883
0.894
0.902
0.907
0.910
0.912
0.913
0.914
0.915
0.916
0.917
0.918
0.919
0.920
0.921
0.922
0.924
0.929
0.941
0.970
1.027
1.093
1.155
1.234
1.275
1.305
1.320
1.332
1.346
1.358
1.378
1.406
1.426
1.438
1.448
1.460
1.462
1.467
1.476
1.494
1.505
1.517
1.546
1.569
1.586
1.596
1.603
1.605
71
-------
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
0.482
0.483
0.484
0.485
0.488
0.494
0.497
0.500
0.501
0.503
0.504
0.506
0.509
0.511
0.513
0.515
0.516
0.518
0.519
0.521
0.522
0.524
0.525
0.527
0.528
0.530
0.531
0.533
0.534
0.537
0.563
0.588
0.604
0.630
0.640
0.656
0.677
0.683
0.686
0.687
0.689
0.698
0.711
0.737
0.764
0.770
0.776
0.788
0.806
0.813
0.824
0.841
0.849
0.041
0.042
0.044
0.044
0.044
0.045
0.045
0.045
0.048
0.049
0.049
0.049
0.051
0.052
0.053
0.053
0.054
0.055
0.056
0.057
0.058
0.058
0.059
0.059
0.060
0.062
0.064
0.066
0.066
0.070
0.077
0.087
0.093
0.099
0.103
0.129
0.151
0.153
0.162
0.178
0.191
0.200
0.208
0.216
0.229
0.239
0.253
0.258
0.262
0.273
0.280
0.284
0.291
0.643
0.644
0.645
0.647
0.651
0.658
0.663
0.666
0.668
0.670
0.672
0.675
0.678
0.681
0.684
0.686
0.688
0.690
0.692
0.694
0.696
0.698
0.700
0.702
0.704
0.706
0.708
0.710
0.712
0.716
0.750
0.784
0.805
0.840
0.853
0.874
0.903
0.910
0.914
0.916
0.919
0.931
0.948
0.983
1.018
1.027
1.035
1.051
1.074
1.084
1.099
1.121
1.132
0.050
0.052
0.054
0.054
0.054
0.055
0.055
0.056
0.059
0.061
0.061
0.061
0.063
0.064
0.065
0.066
0.067
0.068
0.069
0.070
0.071
0.072
0.073
0.073
0.074
0.077
0.079
0.082
0.082
0.086
0.095
0.107
0.115
0.122
0.127
0.159
0.186
0.189
0.200
0.220
0.236
0.247
0.257
0.267
0.283
0.295
0.312
0.318
0.323
0.337
0.345
0.350
0.359
1.036
1.038
1.040
1.040
1.048
1.051
1.060
1.066
1.087
1.149
1.157
1.165
1.171
1.176
1.183
1.186
1.188
1.190
1.194
1.206
1.219
1.230
1.236
1.240
1.249
1.251
1.252
1.259
1.281
1.304
1.320
1.331
1.343
1.383
1.405
1.425
1.445
1.465
1.483
1.500
1.527
1.545
1.582
1.597
1.610
1.622
1.635
1.652
1.670
1.689
1.709
1.727
1.738
0.112
0.114
0.115
0.116
0.119
0.122
0.126
0.130
0.137
0.140
0.141
0.143
0.145
0.147
0.152
0.154
0.156
0.157
0.158
0.159
0.160
0.161
0.162
0.164
0.167
0.169
0.177
0.185
0.190
0.194
0.200
0.207
0.215
0.231
0.257
0.289
0.298
0.302
0.312
0.321
0.333
0.361
0.383
0.406
0.424
0.434
0.475
0.490
0.495
0.507
0.514
0.524
0.535
2.915
2.957
3.015
3.016
3.017
3.021
3.023
3.028
3.035
3.036
3.036
3.036
3.036
3.036
3.036
3.036
3.036
3.036
3.036
3.036
3.037
3.037
3.043
3.075
3.223
3.801
3.894
4.113
4.447
4.950
5.586
6.432
7.279
8.105
8.487
8.554
8.595
8.621
9.135
9.426
9.976
10.469
10.835
11.271
11.770
12.013
12.233
12.447
12.648
12.819
13.415
13.603
13.836
0.364 4.372 0.530 8.605 0.640
0.367 4.435 0.534 8.608 0.646
0.378 4.523 0.550 8.626 0.650
0.381 4.524 0.554 8.650 0.652
0.405 4.525 0.590 8.660 0.738
0.423 4.531 0.616 8.767 0.754
0.439 4.534 0.639 9.029 0.780
0.449 4.542 0.653 9.238 0.795
0.455 4.553 0.662 9.389 0.804
0.469 4.554 0.683 9.493 0.810
0.478 4.554 0.696 9.583 0.815
0.486 4.554 0.708 9.626 0.818
0.495 4.554 0.721 9.669 0.821
0.508 4.554 0.739 9.716 0.825
0.510 4.554 0.742 9.763 0.840
0.510 4.554 0.743 9.809 0.847
0.512 4.554 0.745 9.852 0.855
0.514 4.554 0.748 9.885 0.865
0.516 4.554 0.751 9.932 0.874
0.524 4.554 0.762 9.986 0.891
0.542 4.556 0.789 10.039 0.914
0.543 4.556 0.790 10.072 0.929
0.546 4.565 0.794 10.090 0.937
0.549 4.612 0.799 10.105 0.942
0.553 4.834 0.805 10.146 0.949
0.578 5.702 0.842 10.245 1.375
0.680 5.841 0.990 10.397 1.576
0.713 6.170 1.038 10.923 1.943
0.932 6.670 1.357 11.970 2.820
1.000 7.425 1.455 13.421 3.281
1.062 8.379 1.546 15.289 3.483
1.253 9.648 1.824 15.912 3.620
1.887 10.918 2.746 16.530 4.168
2.111 12.157 3.073 17.622 4.338
2.496 12.731 3.633 18.366 4.682
3.095 12.831 4.505 19.869 5.633
3.402 12.892 4.952 20.711 6.137
3.610 12.932 5.254 22.319 6.853
3.937 13.702 5.730 23.751 7.136
4.157 14.139 6.051 24.842 7.320
4.351 14.964 6.333 25.410 7.685
4.459 15.704 6.490 25.798 8.052
4.669 16.253 6.796 26.122 8.344
4.950 16.907 7.205 26.353 8.602
5.600 17.655 8.151 26.638 8.898
5.654 18.020 8.230 27.219 9.251
5.898 18.349 8.584 27.279 10.253
6.046 18.671 8.800 27.320 10.828
6.078 18.972 8.847 27.352 10.933
6.124 19.228 8.913 27.822 11.060
6.267 20.123 9.122 28.763 11.188
6.549 20.405 9.532 29.402 11.345
7.046 20.754 10.256 29.971 11.733
0.854
0.854
0.854
0.854
0.854
0.870
0.881
0.887
0.898
0.917
0.941
0.954
0.965
0.978
0.980
0.984
0.988
0.991
0.994
0.996
0.999
1.004
1.008
1.013
1.018
1.024
1.034
1.061
1.100
1.136
1.169
1.193
1.231
1.289
1.333
1.374
1.439
1.479
1.510
1.575
1.650
1.688
1.703
1.726
1.739
1.751
1.762
1.790
1.817
1.847
1.877
1.909
1.940
1.139
1.139
1.139
1.139
1.139
1.160
1.174
1.183
1.197
1.223
1.255
1.272
1.286
1.304
1.307
1.312
1.317
1.321
1.325
1.328
1.332
1.338
1.344
1.350
1.357
1.365
1.379
1.414
1.466
1.514
1.559
1.591
1.641
1.719
1.777
1.832
1.919
1.972
2.013
2.100
2.200
2.251
2.270
2.301
2.318
2.335
2.349
2.387
2.423
2.462
2.503
2.545
2.586
1.606
1.607
1.607
1.608
1.614
1.616
1.631
1.643
1.656
1.673
1.703
1.739
1.767
1.774
1.785
1.806
1.830
1.844
1.845
1.846
1.852
1.868
1.877
1.879
1.886
1.900
1.910
1.936
1.954
1.986
2.050
2.131
2.235
2.320
2.395
2.488
2.563
2.645
2.746
2.778
2.792
2.810
2.847
2.874
2.905
2.950
3.001
3.047
3.104
3.173
3.238
3.302
3.372
72
-------
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
0.864
0.871
0.876
0.881
0.886
0.891
0.902
0.914
0.925
0.938
0.941
0.944
0.949
0.960
0.970
0.976
0.985
0.993
0.999
1.006
1.018
1.031
1.044
1.056
1.067
1.075
1.082
1.090
1.097
1.101
1.103
1.106
1.109
1.111
1.113
1.115
1.118
1.120
1.128
1.142
1.160
1.162
1.172
1.181
1.184
1.188
1.192
1.193
1.197
1.199
1.203
1.208
1.209
0.314
0.322
0.324
0.326
0.328
0.339
0.348
0.358
0.370
0.383
0.395
0.406
0.413
0.415
0.416
0.418
0.420
0.427
0.438
0.443
0.448
0.453
0.456
0.459
0.463
0.466
0.469
0.482
0.490
0.497
0.504
0.508
0.517
0.521
0.521
0.523
0.527
0.531
0.537
0.544
0.547
0.554
0.562
0.568
0.569
0.574
0.574
0.574
0.575
0.575
0.576
0.577
0.577
1.152
1.161
1.168
1.175
1.181
1.188
1.203
1.219
1.233
1.251
1.255
1.258
1.265
1.280
1.293
1.301
1.313
1.324
1.332
1.341
1.357
1.375
1.392
1.408
1.422
1.433
1.443
1.453
1.463
1.468
1.470
1.474
1.478
1.481
1.484
1.487
1.490
1.493
1.504
1.522
1.547
1.549
1.562
1.574
1.579
1.584
1.589
1.590
1.596
1.598
1.604
1.610
1.612
0.387
0.398
0.400
0.402
0.405
0.418
0.429
0.442
0.457
0.473
0.487
0.501
0.510
0.512
0.514
0.516
0.518
0.527
0.540
0.547
0.553
0.559
0.563
0.567
0.571
0.575
0.579
0.595
0.605
0.614
0.622
0.627
0.638
0.643
0.643
0.645
0.651
0.655
0.663
0.671
0.675
0.684
0.694
0.701
0.702
0.708
0.708
0.709
0.710
0.710
0.711
0.712
0.712
1.755
1.778
1.795
1.808
1.820
1.825
1.827
1.829
1.834
1.847
1.862
1.876
1.891
1.906
1.920
1.933
1.945
1.953
1.959
1.977
1.991
2.011
2.037
2.058
2.079
2.089
2.097
2.109
2.123
2.138
2.150
2.158
2.165
2.171
2.178
2.185
2.192
2.195
2.200
2.205
2.208
2.212
2.214
2.216
2.217
2.218
2.219
2.221
2.223
2.225
2.227
2.228
2.228
0.547
0.560
0.574
0.585
0.589
0.589
0.598
0.607
0.617
0.621
0.629
0.638
0.649
0.664
0.679
0.693
0.706
0.719
0.726
0.737
0.745
0.752
0.800
0.805
0.817
0.836
0.839
0.846
0.866
0.879
0.882
0.891
0.905
0.917
0.918
0.919
0.941
0.952
0.957
0.963
0.970
0.975
0.979
0.985
0.988
0.992
0.995
0.996
0.996
0.996
0.997
0.997
0.999
14.456
14.637
15.100
15.326
15.690
15.917
16.012
16.309
16.457
16.621
16.792
16.979
17.085
17.164
17.233
17.316
17.427
17.483
17.559
17.698
17.879
18.035
18.262
18.334
18.421
18.535
18.635
18.803
19.029
19.331
19.333
19.337
19.387
19.521
19.655
19.823
19.869
19.881
19.898
19.908
19.915
20.005
20.084
20.085
20.085
20.139
20.209
20.215
20.217
20.245
20.274
20.277
20.285
7.463 21.684 10.862 30.276 12.598
7.555 21.955 10.996 30.988 12.953
7.699 22.650 11.206 31.095 13.213
7.911 22.989 11.514 31.314 14.131
8.172 23.535 11.894 31.833 14.839
8.258 23.876 12.019 32.239 15.137
8.361 24.018 12.170 32.547 15.138
8.600 24.464 12.517 32.855 15.141
8.655 24.685 12.598 33.153 15.595
8.674 24.931 12.625 33.444 15.658
8.693 25.188 12.653 33.482 15.704
8.778 25.468 12.777 33.516 15.729
8.867 25.627 12.906 33.549 16.058
8.924 25.746 12.989 33.653 16.987
8.973 25.850 13.060 33.973 17.064
9.045 25.974 13.165 34.159 17.073
9.098 26.141 13.242 34.191 17.153
9.215 26.225 13.412 34.250 17.332
9.386 26.338 13.662 34.469 17.406
9.463 26.547 13.773 34.716 17.641
9.579 26.818 13.942 34.969 17.922
9.680 27.052 14.090 35.144 18.484
9.773 27.393 14.224 35.418 18.553
9.911 27.501 14.426 35.766 18.658
9.961 27.632 14.498 35.949 18.953
10.152 27.803 14.776 36.010 19.266
10.242 27.953 14.907 36.548 19.309
10.248 28.205 14.916 37.179 19.731
10.315 28.543 15.014 37.651 19.902
10.458 28.997 15.221 38.041 20.012
10.630 29.000 15.472 38.591 20.260
10.687 29.005 15.555 38.852 20.739
10.754 29.081 15.652 38.861 21.346
10.971 29.281 15.969 38.926 21.810
11.012 29.483 16.028 39.194 22.001
11.250 29.734 16.375 39.474 22.290
11.327 29.803 16.487 39.668 22.324
11.353 29.821 16.524 39.781 22.343
11.390 29.847 16.578 39.890 22.522
11.463 29.862 16.684 39.954 22.661
11.511 29.873 16.755 39.984 22.666
11.522 30.008 16.770 39.989 22.667
11.546 30.126 16.805 39.990 22.668
11.587 30.127 16.865 39.990 22.669
11.652 30.127 16.960 39.990 22.670
11.652 30.208 16.960 39.991 22.671
11.654 30.314 16.962 40.012 22.671
11.672 30.323 16.988 40.061 22.672
11.729 30.325 17.072 40.116 22.673
11.744 30.368 17.094 40.249 22.673
11.806 30.411 17.184 40.253 22.673
11.808 30.416 17.187 40.290 22.674
11.809 30.428 17.188 40.385 22.675
1.970
2.005
2.062
2.103
2.138
2.171
2.198
2.228
2.265
2.308
2.349
2.389
2.414
2.451
2.474
2.513
2.555
2.600
2.623
2.636
2.638
2.639
2.642
2.659
2.678
2.700
2.714
2.729
2.765
2.799
2.843
2.875
2.918
2.949
2.970
2.998
3.010
3.026
3.029
3.038
3.050
3.053
3.054
3.054
3.055
3.055
3.055
3.055
3.056
3.056
3.056
3.056
3.057
2.627
2.673
2.749
2.804
2.851
2.894
2.931
2.971
3.020
3.077
3.132
3.185
3.219
3.268
3.299
3.350
3.406
3.466
3.497
3.514
3.517
3.519
3.523
3.545
3.570
3.600
3.619
3.639
3.686
3.732
3.791
3.833
3.890
3.932
3.960
3.997
4.013
4.035
4.038
4.050
4.066
4.070
4.072
4.072
4.073
4.073
4.073
4.073
4.074
4.074
4.075
4.075
4.076
3.452
3.545
3.648
3.701
3.759
3.821
3.870
3.892
3.914
3.955
3.997
4.035
4.089
4.146
4.206
4.243
4.295
4.351
4.398
4.410
4.419
4.426
4.429
4.453
4.486
4.542
4.598
4.638
4.715
4.774
4.829
4.872
4.931
4.960
4.963
4.965
4.968
4.971
4.974
4.977
4.979
4.980
4.981
4.982
4.983
4.984
4.985
4.986
4.987
4.988
4.989
4.990
4.991
73
-------
237
238
239
1.210 0.577 1.613 0.712 2.229 1.001
1.211 0.578 1.614 0.713 2.230 1.004
1.211 0.580 1.615 0.716 2.231 1.007
20.287 11.810 30.430 17.189 40.488 22.675
20.301 11.845 30.452 17.241 40.720 22.675
20.325 11.934 30.488 17.370 40.763 22.677
3.057 4.076 4.992
3.057 4.076 4.993
3.057 4.076 4.994
74
-------
Appendix D
Fast Pass IM240 Standards: Modal Regression Technique
Developed by Sierra Research
Contract 68-C4-0056 Work Assignment 2-04
75
-------
Fast Pass IM240 Standards: Modal Regression Technique
Sierra Research
Contract 68-C4-0056 Work Assignment 2-04
Development of Fast-Pass Standards
This method differs from those presented in Appendices A, B, and C in that second-by-second standards are not used,
rather the second-by-second emissions are used to project a final IM240 score which is then compared to the appropriate IM240
standard as listed on pages 1-4 of this document. A sample of the regression coefficients used to project the full IM240 scores
are presented in this appendix. The complete set of coefficients, including an example calculation, can be downloaded from the
EPA web site.
Full-duration, second-by-second IM240 data collected in the Arizona I/M program were used for this analysis. Nearly
110,000 individual tests were in the database used in the analysis, which is comprised of all full-duration IM240 tests conducted
in Arizona from April 1995 through April 1997. Regression coefficients were generated separately for light-duty gasoline
vehicles (i.e., passenger cars) and light-duty trucks for the following model year groups listed below.
• 1981 to 1984,
• 1985 to 1989, and
• 1990 and later.
Regression coefficients were developed for HC, CO, and NOx and for both the composite IM240 and for Phase 2 of
the IM240 after dividing the IM240 drive trace into 24 separate modes. The Phase 2 regressions used mode 11 as the first mode
and continued through mode 23. The composite IM240 regressions used modes 1 through 23. (Although the trace was divided
into 24 modes, if a fast-pass decision is not made by mode 23, then the vehicle would run the full DVI240. At that point, a
pass/fail decision should be made on the actual IM240 score, not the predicted score.) Finally, it is recommended that the first
mode at which a pass/fail decision should be made is mode 4 (which ends at second 32 of the IM240) for a composite IM240
prediction, or mode 13 (which ends at second 113 of the IM240) for a Phase 2 prediction.
The regression coefficients for a 0.8 g/mi HC composite IM240 cutpoint are given in this appendix, along with the
coefficients for a 0.5 g/mi HC Phase 2 IM240 cutpoint. The full series of regression coefficients developed in this effort were
provided to EPA electronically, and are available on the OMS web page.
Using the 2% Random Sample from the Arizona program (which consists of 26,000 records), pass/fail rates were
calculated with the modal regression procedures outlined above as well as the current fast-pass cutpoint tables. This analysis
was performed using the final IM240 HC, CO, and NOx standards, and the results are presented in Table Dl.
As observed in Table D1, the revised fast-pass methodology results in a lower fraction of false passes than the current
method, particularly for older cars. However, this improvement in failing vehicle identification is offset by a longer average test
time for passing vehicles in the older model year groups. For newer vehicles (i.e., 1990 and later), the revised methodology
results in significant improvements in average test time, without a significant increase in the fraction of false passes.
76
-------
Table Dl
Comparison of Current and Revised Fast-Pass Methodologies Under the Final IM240 Standards
(26,000 Vehicle Sample)
Vehicle
Class
LDV
LOT
Model
Year
Group
81-84
85-89
1990+
81-84
85-89
1990+
"True"
Failure
Ratea
79%
45%
8%
62%
42%
9%
Current Fast-Pass
Failure
Rate
76%
41%
7%
51%
35%
7%
Pass Time
(seconds)
125
130
88
71
70
60
Revised Fast-Pass
Failure
Rate
78%
43%
7%
60%
40%
7%
Pass Time
(seconds)
157
121
57
113
93
57
a The "true" failure rate is based on full-duration IM240 test scores.
77
-------
Composite IM240 HC Regression Coefficients Developed from Modal IM240 Data Analysis
1981-1984 Model Year Light-Duty Gasoline Vehicles
0.8 g/mi Cutpoint
Mode
Ml
M2
M3
M4
M5
M6
M7
M8
M9
M10
Mil
M12
Ml 3
M14
Ml 5
Ml 6
Ml 7
Ml 8
Ml 9
M20
M21
M22
M23
RMS
Error
0.301
0.253
0.247
0.232
0.228
0.214
0.202
0.194
0.189
0.185
0.182
0.160
0.151
0.149
0.146
0.144
0.140
0.138
0.134
0.102
0.068
0.041
0.030
Const
0.566
0.378
0.371
0.337
0.325
0.286
0.274
0.260
0.247
0.242
0.236
0.179
0.160
0.156
0.152
0.150
0.142
0.140
0.128
0.058
0.032
0.013
0.007
Regression Coefficients
Cl
5.043
0.187
-0.383
-0.363
-0.454
0.371
0.697
0.489
0.452
0.163
-0.613
0.127
0.257
0.285
0.397
0.428
0.463
0.505
0.506
0.441
0.507
0.518
0.517
C2
2.802
2.022
0.828
1.046
0.566
0.468
0.715
0.747
0.947
1.036
0.496
0.519
0.535
0.612
0.652
0.579
0.566
0.528
0.520
0.551
0.516
0.526
C3
2.586
0.771
-0.497
0.327
0.136
-0.044
0.049
-0.410
-0.076
0.458
0.463
0.377
0.326
0.276
0.511
0.462
0.820
0.567
0.501
0.564
0.512
C4
3.854
2.884
-0.040
-0.077
-0.411
-0.370
-0.223
-0.458
-0.049
-0.050
0.080
-0.091
-0.140
-0.148
-0.015
-0.205
0.283
0.508
0.503
0.515
C5
3.156
1.592
1.315
1.211
1.228
0.801
0.652
0.861
0.494
0.324
0.754
0.404
0.619
0.443
0.294
0.334
0.307
0.329
0.448
C6
4.850
2.032
2.268
2.028
1.855
1.882
0.657
0.783
0.741
0.525
0.656
0.189
0.386
0.539
0.275
0.466
0.622
0.487
C7
2.632
0.853
0.757
0.909
0.997
0.532
0.574
0.578
0.543
0.668
0.756
0.676
0.735
0.678
0.393
0.398
0.455
C8
2.410
0.664
0.463
0.312
0.742
0.498
0.480
0.420
0.406
0.455
0.317
0.259
0.396
0.487
0.508
0.519
C9
2.993
2.017
1.900
0.756
0.793
0.878
0.631
0.658
0.462
0.386
0.147
0.600
0.542
0.395
0.429
CIO
2.189
1.397
1.363
1.013
0.729
0.591
0.454
0.632
0.622
1.098
1.082
1.195
1.055
0.938
Cll
4.130
1.119
1.266
1.310
0.768
-0.393
-0.086
-0.033
-0.693
0.232
0.446
0.557
0.682
C12
2.786
2.081
2.069
1.894
1.833
1.551
1.600
1.478
0.525
0.329
0.394
0.389
C13
2.388
1.748
1.505
1.390
1.247
1.086
0.929
0.815
0.563
0.483
0.577
C14
1.228
0.562
0.498
0.516
0.435
0.550
0.244
0.546
0.526
0.509
CIS
2.644
1.810
0.846
0.399
0.693
0.831
0.500
0.715
0.500
C16
1.915
1.432
1.133
0.252
1.083
0.690
0.469
0.654
C17
2.815
1.908
1.463
0.721
0.700
0.615
0.403
CIS
1.738
1.566
1.244
0.763
0.618
0.575
C19
1.476
0.809
0.805
0.444
0.458
C20
0.931
0.426
0.540
0.517
C21
1.089
0.430
0.386
C22
1.148
0.681
C23
0.819
NOTE: Results for only 23 modes are shown here because if the 24th mode is completed the actual IM240 score would then be used rather than the predicted score.
78
-------
Phase 2 IM240 HC Regression Coefficients Developed from Modal IM240 Data Analysis
1981-1984 Model Year Light-Duty Gasoline Vehicles
0.5 g/mi Cutpoint
Mode
Number
Pll
P12
P13
P14
P15
P16
P17
P18
P19
P20
P21
P22
P23
RMS
Error
0.179
0.145
0.136
0.134
0.131
0.129
0.125
0.122
0.118
0.086
0.061
0.039
0.029
Reg.
Const.
0.346
0.219
0.198
0.192
0.188
0.184
0.171
0.168
0.154
0.076
0.041
0.016
0.007
Regression Coefficients
Cll
8.141
2.349
1.727
1.330
0.571
-0.983
-0.505
-0.516
-0.904
0.344
0.994
1.142
1.198
C12
3.104
2.209
2.210
.862
.887
.456
.481
.381
0.701
0.508
0.562
0.561
C13
2.823
2.034
1.732
1.610
1.415
1.215
1.041
0.965
0.691
0.700
0.777
C14
1.470
0.807
0.588
0.728
0.533
0.803
0.539
0.796
0.745
0.755
C15
2.665
1.883
0.712
0.276
0.703
1.035
0.735
1.010
0.770
C16
2.208
1.820
1.426
0.602
1.357
1.173
0.779
1.005
C17
3.193
2.227
1.573
0.881
0.792
0.752
0.484
CIS
1.985
1.758
1.678
1.146
0.874
0.833
C19
1.711
0.988
0.925
0.560
0.607
C20
1.091
0.640
0.732
0.715
C21
1.372
0.647
0.560
C22
1.544
0.975
C23
1.098
NOTE: Results for only modes are presented only for modes 11 through 23. Mode 11 is the first mode of Phase 2 and if the 24th mode is completed the actual IM240 full or
composite score would be used rather than the predicted score.
79
-------
Composite IM240 HC Regression Coefficients Developed from Modal IM240 Data Analysis
1985-1989 Model Year Light-Duty Gasoline Vehicles
0.8 g/mi Cutpoint
Mode
Ml
M2
M3
M4
M5
M6
M7
M8
M9
M10
Mil
M12
M13
M14
M15
M16
M17
M18
M19
M20
M21
M22
M23
RMS
Error
0.301
0.248
0.242
0.224
0.219
0.207
0.194
0.184
0.174
0.171
0.167
0.144
0.137
0.135
0.131
0.129
0.125
0.122
0.116
0.085
0.055
0.035
0.024
Const
0.430
0.259
0.255
0.223
0.212
0.189
0.181
0.169
0.157
0.154
0.150
0.106
0.095
0.091
0.089
0.087
0.081
0.080
0.070
0.029
0.018
0.009
0.004
Regression Coefficients
Cl
5.602
0.159
-0.183
0.012
-0.084
0.424
0.649
0.369
0.342
0.180
-0.536
0.170
0.153
0.169
0.272
0.278
0.348
0.348
0.355
0.432
0.542
0.575
0.574
C2
3.044
2.108
1.015
1.168
0.758
0.668
0.880
0.927
1.101
1.168
0.593
0.601
0.583
0.609
0.683
0.641
0.651
0.591
0.465
0.524
0.503
0.499
C3
2.824
0.555
-0.763
-0.026
-0.372
-0.438
-0.266
-0.631
-0.318
0.221
0.146
0.126
0.139
0.092
0.274
0.147
0.583
0.545
0.385
0.544
0.516
C4
3.864
2.919
0.591
0.443
0.037
-0.055
0.068
-0.082
0.266
0.360
0.499
0.358
0.322
0.241
0.387
0.180
0.443
0.537
0.511
0.525
C5
3.395
1.742
1.314
1.302
1.335
0.949
0.705
0.883
0.542
0.226
0.572
0.166
0.418
0.291
0.199
0.311
0.398
0.339
0.455
C6
4.092
1.053
1.440
1.391
1.233
1.264
0.515
0.548
0.547
0.388
0.487
0.209
0.439
0.559
0.226
0.546
0.596
0.493
C7
3.066
0.797
0.656
0.822
0.846
0.448
0.519
0.530
0.544
0.671
0.775
0.622
0.697
0.677
0.373
0.434
0.482
C8
2.830
0.035
-0.082
-0.127
0.428
0.277
0.265
0.195
0.212
0.207
0.115
0.082
0.359
0.556
0.512
0.528
C9
4.534
3.332
3.103
1.462
1.402
1.482
1.174
1.115
0.887
0.812
0.426
0.604
0.462
0.371
0.353
CIO
2.217
1.373
1.314
1.109
0.760
0.605
0.457
0.657
0.631
1.018
1.148
1.214
1.085
0.981
Cll
4.334
1.001
1.248
1.225
0.985
-0.039
0.145
0.217
-0.368
0.387
0.466
0.490
0.668
C12
2.829
2.159
2.183
1.914
1.831
1.602
1.651
1.511
0.555
0.368
0.400
0.420
C13
2.122
1.358
1.217
1.143
0.944
0.809
0.738
0.731
0.484
0.498
0.558
C14
1.490
0.696
0.626
0.500
0.246
0.346
0.187
0.520
0.500
0.534
CIS
2.684
1.714
0.969
0.548
0.826
1.034
0.679
0.819
0.542
C16
2.124
1.584
1.358
0.523
0.908
0.708
0.484
0.577
C17
2.648
1.605
1.293
0.755
0.564
0.555
0.422
CIS
1.837
1.374
1.211
0.703
0.610
0.576
C19
1.818
0.916
0.808
0.493
0.522
C20
0.953
0.426
0.533
0.504
C21
1.126
0.467
0.427
C22
1.096
0.599
C23
0.842
NOTE: Results for only 23 modes are shown here because if the 24th mode is completed the actual IM240 score would then be used rather than the predicted score.
80
-------
Phase 2 IM240 HC Regression Coefficients Developed from Modal IM240 Data Analysis
1985-1989 Model Year Light-Duty Gasoline Vehicles
0.5 g/mi Cutpoint
Mode
Number
Pll
P12
P13
P14
P15
P16
P17
P18
P19
P20
P21
P22
P23
RMS
Error
0.177
0.140
0.132
0.129
0.125
0.123
0.118
0.115
0.109
0.077
0.057
0.037
0.027
Reg.
Const.
0.259
0.150
0.131
0.125
0.121
0.119
0.109
0.107
0.094
0.041
0.025
0.013
0.006
Regression Coefficients
Cll
9.328
2.179
1.779
1.374
0.861
-0.368
0.059
-0.009
-0.526
0.637
0.945
0.917
1.052
C12
3.452
2.527
2.545
2.070
2.053
1.736
1.760
1.622
0.716
0.562
0.590
0.609
C13
2.741
1.628
1.387
1.269
1.014
0.833
0.698
0.900
0.700
0.738
0.774
C14
1.888
1.001
0.818
0.823
0.559
0.823
0.635
0.868
0.748
0.810
C15
2.991
2.160
1.032
0.556
0.762
1.081
0.834
1.105
0.757
C16
2.195
1.762
1.401
0.636
1.205
1.063
0.785
0.906
C17
3.119
2.128
1.569
1.005
0.867
0.740
0.536
CIS
2.030
1.573
1.455
0.971
0.839
0.802
C19
2.175
1.267
1.063
0.583
0.675
C20
1.123
0.658
0.740
0.711
C21
1.363
0.631
0.575
C22
1.554
0.903
C23
1.137
NOTE: Results for only modes are presented only for modes 11 through 23. Mode 11 is the first mode of Phase 2 and if the 24th mode is completed the actual IM240 full or
composite score would be used rather than the predicted score.
81
-------
Composite IM240 HC Regression Coefficients Developed from Modal IM240 Data Analysis
1990+ Model Year Light-Duty Gasoline Vehicles
0.8 g/mi Cutpoint
Mode
Ml
M2
M3
M4
M5
M6
M7
M8
M9
M10
Mil
M12
M13
M14
M15
M16
M17
M18
M19
M20
M21
M22
M23
RMS
Error
0.368
0.271
0.253
0.230
0.221
0.207
0.192
0.175
0.162
0.155
0.149
0.123
0.115
0.113
0.107
0.102
0.098
0.095
0.090
0.068
0.041
0.027
0.019
Const.
0.162
0.028
0.036
0.031
0.026
0.021
0.025
0.030
0.032
0.034
0.037
0.028
0.025
0.025
0.027
0.027
0.026
0.026
0.023
0.009
0.007
0.003
0.002
Regression Coefficients
Cl
10.855
0.252
0.096
0.720
0.391
0.862
1.279
1.076
1.111
0.742
-0.292
0.433
0.578
0.618
0.747
0.719
0.794
0.769
0.816
0.575
0.544
0.559
0.553
C2
4.621
2.693
0.868
1.110
0.623
0.372
0.515
0.490
0.835
0.916
0.321
0.296
0.262
0.284
0.462
0.426
0.455
0.385
0.360
0.483
0.500
0.496
C3
4.788
1.740
0.060
1.005
0.699
0.477
0.510
-0.133
0.270
0.650
0.562
0.555
0.574
0.356
0.518
0.367
0.654
0.539
0.489
0.535
0.515
C4
4.997
3.325
0.397
0.393
0.150
0.142
0.470
0.141
0.528
0.394
0.503
0.244
0.136
0.062
0.197
0.080
0.382
0.528
0.538
0.537
C5
5.174
2.743
2.028
1.178
1.351
0.754
0.342
0.818
0.374
-0.034
0.529
0.065
0.242
0.174
0.083
0.257
0.539
0.444
0.525
C6
5.132
1.127
1.750
1.370
0.829
0.923
-0.003
0.234
0.227
0.033
0.303
0.168
0.420
0.642
0.458
0.520
0.602
0.518
C7
3.732
0.608
0.587
0.980
1.049
0.245
0.492
0.569
0.676
0.778
0.786
0.710
0.717
0.639
0.388
0.406
0.438
C8
3.725
0.494
0.287
0.326
1.037
0.715
0.714
0.571
0.668
0.737
0.561
0.557
0.556
0.588
0.514
0.535
C9
5.180
3.033
2.661
0.672
0.629
0.776
0.487
0.345
0.079
0.016
-0.358
0.034
0.284
0.284
0.349
CIO
3.511
2.172
2.127
1.553
1.121
1.011
0.659
0.882
0.870
1.269
1.205
1.157
0.992
0.870
Cll
5.629
1.234
1.271
1.069
0.912
-0.008
0.127
0.128
-0.488
0.514
0.523
0.497
0.650
C12
3.583
2.743
2.758
2.369
2.189
1.928
2.015
1.916
0.804
0.367
0.407
0.429
C13
2.839
1.607
1.258
1.033
0.726
0.442
0.340
0.472
0.461
0.518
0.549
C14
2.069
0.591
0.401
0.488
0.256
0.282
0.255
0.575
0.526
0.567
CIS
3.362
2.153
1.245
0.759
0.819
0.693
0.548
0.656
0.521
C16
2.766
1.994
1.521
0.888
1.266
0.853
0.637
0.624
C17
2.960
1.733
1.357
0.881
0.677
0.661
0.554
CIS
2.083
1.477
1.203
0.674
0.573
0.536
C19
1.846
0.837
0.583
0.470
0.443
C20
1.073
0.370
0.497
0.510
C21
1.309
0.525
0.387
C22
1.112
0.654
C23
0.853
NOTE: Results for only 23 modes are shown here because if the 24th mode is completed the actual IM240 score would then be used rather than the predicted score.
82
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Phase 2 IM240 HC Regression Coefficients Developed from Modal IM240 Data Analysis
1990+ Model Year Light-Duty Gasoline Vehicles
0.5 g/mi Cutpoint
Mode
Number
Pll
P12
P13
P14
P15
P16
P17
P18
P19
P20
P21
P22
P23
RMS
Error
0.153
0.114
0.102
0.099
0.095
0.091
0.088
0.085
0.081
0.057
0.040
0.028
0.020
Reg.
Const.
0.098
0.048
0.041
0.039
0.040
0.040
0.038
0.038
0.035
0.016
0.010
0.005
0.003
Regression Coefficients
Cll
13.195
3.112
1.873
1.406
1.107
-0.030
0.165
0.093
-0.272
0.581
0.817
0.823
0.909
C12
4.074
2.680
2.668
2.141
2.065
1.791
1.843
1.779
0.846
0.585
0.606
0.612
C13
3.765
2.167
1.738
1.365
1.043
0.719
0.514
0.727
0.723
0.751
0.790
C14
2.454
1.122
0.858
0.931
0.663
0.829
0.616
0.936
0.837
0.837
C15
3.342
2.119
1.028
0.610
0.678
0.627
0.588
0.740
0.609
C16
3.157
2.401
1.854
1.356
1.840
1.434
1.015
0.957
C17
3.357
2.189
1.669
1.313
1.014
0.843
0.714
CIS
2.206
1.515
1.345
0.886
0.855
0.775
C19
1.952
0.856
0.731
0.581
0.632
C20
1.195
0.623
0.717
0.719
C21
1.512
0.749
0.591
C22
1.426
0.868
C23
1.158
NOTE: Results for only modes are presented only for modes 11 through 23. Mode 11 is the first mode of Phase 2 and if the 24th mode is completed the actual IM240 full or
composite score would be used rather than the predicted score.
83
-------
Appendix E
Calculation of Raw Emission Scores from Dilute Measurements
84
-------
Calculation of Raw Emission Scores from Dilute Measurements
The constant volume sampling technique, which has been part of the FTP for the exhaust emissions testing of
passenger cars and light-duty trucks since the 1972 model year, involves the collection of a sample of exhaust gas after
it has been diluted to a known, constant volume. Using this procedure, a device called a "constant volume sampler"
dilutes the vehicle exhaust and then samples a constant volume fraction of the dilute mixture. In a typical test facility,
the dilution is achieved by drawing "background" air from the room where the vehicle is being driven on a chassis
dynamometer. A slipstream from the diluted exhaust is pumped into a series of sample bags during the test. Three
sample bags are used for dilute exhaust samples: the first represents the "cold start" phase of the test, the second
represents "stabilized" operation, and the third represents the "hot start" phase of the test. Samples of background air are
simultaneously collected in three additional bags. At the end of the test, measurement of the concentration of pollutants
in the sample bags and calculation of the total flow of the dilute mixture during each phase allows the mass of emissions
emitted during each phase of the test to be calculated. Division of the calculated mass by the associated driving distance
provides the mass emissions rate (normally expressed in grams per mile).
A variation of the FTP test procedure is used in CVS-based I/M testing. Instead of filling sample bags with
dilute mixture during separate phases of the test, the concentrations of pollutants in the dilute exhaust stream are
continuously monitored. Mass emissions per mile of travel are calculated from integration of the continuous
measurements divided by the distance driven during the test. (This technique facilitates the use of "fast pass" and "fast
fail" algorithms for shortening the test in cases where a vehicle is extremely clean or extremely dirty during the early
portion of the test.)
In CVS-based testing, the volume of background (dilution) air in the sample substantially exceeds the volume
of exhaust gas, usually by a factor often or more. As a result, the extent to which the dilution air is contaminated with
pollutants can significantly affect the calculated mass emissions. To eliminate this interference, the extent to which the
vehicle exhaust has been diluted must be known. The FTP specifies that the ratio of total volume to exhaust volume
("dilution factor") be calculated using the following equation:
13.4
m DFEPA =
C02e+COe+HCe
where: CC^g, COe, and HCe are the concentrations measured in the dilute sample expressed as percent volume.
In the above equation, the DF calculated in accordance with the FTP is specified as "DFgp^" to distinguish it
from an improved formulation of the DF discussed below. As noted above, DFgp^ is used in the FTP to correct the
emissions concentration in the sample bag for pollutants in the dilution (background) air. Although not required by the
FTP, the average DF can also be used to calculate the average concentration of the undiluted tailpipe emissions emitted
while the sample bag was being filled. If there were no pollutants in the dilution air, the tailpipe concentrations could be
calculated simply by multiplying the dilute measurement by the DF:
85
-------
[2] Ctp = Cconc * DF
where: Ctp is the actual raw tailpipe concentration, and Cconc is the concentration of a pollutant in the dilute sample
defined as:
where Ce is the pollutant dilute concentration and Cd is the pollutant background concentration.
Substituting [3] into [2] yields:
[4] Ctp =
Ce-Cd 1 —
DF
DF
As noted above, the CVS technique used to measure emissions in I/M programs involves calculating mass
emissions by integrating the continuously monitored dilute sample. An average dilution factor can still be calculated
from the integrated average of the dilute emissions. The DF can also be calculated continuously and used to calculate
the undiluted tailpipe concentration at any point in time. This capability makes it possible to use the CVS emissions
measurement system to determine whether a vehicle meets emissions standards that are based on tailpipe concentrations.
If, for example, a CO concentration of 0.1% is measured in the dilute exhaust stream, and if the calculated DF is 10,
then the tailpipe emission concentration would be calculated to be 1.0% CO (assuming background concentrations were
zero).
Although there are several advantages associated with the use of the reverse dilution calculation method, some
error is introduced in the calculation of the tailpipe concentration due to the discrepancies that can exist between actual
test conditions and the assumptions on which the standard DF calculation is based. As described in detail in a
previously referenced technical paper (SAE paper 980678), the DF equation contained in the FTP is based on three
assumptions:
1. Exhaust emissions of vehicles are the product of a chemically balanced (i.e., stoichiometric) ratio of air and
fuel;
2.The concentrations of pollutants in the background air have an insignificant effect on the calculation of the
DF; and
3. No water vapor has been removed from the sample.
Each of these assumptions is problematic when the reverse dilution technique is used to calculate the
concentration of pollutants in a vehicle tailpipe that would otherwise be measured directly in an I/M program. First,
although most vehicles run very close to a stoichiometric air-fuel ratio, this is not always the case. Second, in the
86
-------
environment of an I/M test lane, pollution in the background air can be significant. Third, analyzers routinely used for
raw exhaust measurement remove a substantial amount of water from the sample.3
A more complicated expression of the DF is required to address the limitations of the DF equation contained in
the FTP. The recommended equation is as follows:4
100-Ki(CQ2d)-K2(cOd)-K3(HCd)
Dr =
where: KI, K^, and Kg are constants that depend on the fuel type (see below);
C()2d is the concentration of CC>2 in the background air;
CO^ is the concentration of CO in the background air;
HC^ is the concentration of HC in the background air;
CO2e is the concentration of CC>2 in the dilute sample;
po
e is the concentration of CO in the dilute sample; and
HCe is the concentration of HC in the dilute sample.
All of the concentrations in the above equation are expressed in volume percent. The HC values are expressed
in hexane equivalent. The values of Kj, K^, and Kg depend on the type of fuel and whether the calculated pollutant
concentrations are on a wet or dry basis. When attempting to match measurements that would be made by typical
systems for raw exhaust measurement, the values for dry exhaust should be used. For gasoline fuel with pollutant
concentrations measured on a wet basis, such as in IM240 set-ups, the value of Kj is 6.5431, the value for ^ is 4.6561,
and the value of Kg is 57.0945.
Dilution Correction of Tailpipe Measurements
As noted earlier, one of the problems associated with I/M standards based on maximum allowable tailpipe
concentrations is that certain causes of dilution (e.g., air injection,5 exhaust leaks, or inadequate sample probe insertion
So-called "BAR90" analyzers actually use a condensate removal system to dispose of the water that condenses
when raw exhaust is drawn through the sample probe; however, the efficiency of water removal depends on the
temperature of the exhaust sample because no temperature control is provided by the analyzer.
The DF equation in the previously referenced SAE paper is based on the simplifying assumption that there is no
residual oxygen in the exhaust of stoichiometric or richer air-fuel mixtures. This assumption holds unless there is
substantial misfire. In the case of misfire, the exhaust may contain oxygen that dilutes the concentration of other
constituents. Equation 4 is a refinement of the equation contained in the SAE paper that accounts for misfire.
Air injection can reduce mass emissions by facilitating more complete combustion in either the exhaust manifold or
the catalytic converter. However, the dilution associated with air injection causes the measured concentration to be
87
-------
depth) may cause measured concentrations to be substantially lower than for another vehicle with identical mass
emissions. Because of this problem, EPA guidance for concentration measurement during simple I/M tests specifies
that the sum of CO plus CC^ emissions should be at least 6% in order for the test to be considered valid. Although the
basis for the recommendation is not documented, it appears to represent the maximum level of exhaust dilution that
might be expected with a relatively high output air injection system installed on a relatively small engine. As a result, it
allows the exhaust concentration to be reduced by more than 50% due to various sources of dilution.6 It is therefore a
relatively ineffective means of preventing exhaust dilution from affecting the results of an I/M test.
Recently, the California Bureau of Automotive Repair (BAR) devised an improved procedure for eliminating
the effects of exhaust dilution. BAR's procedure uses equations developed from basic combustion chemistry to
determine the extent to which an exhaust sample must have been diluted before a concentration measurement was made.
The measured concentrations are adjusted to what they would be under stoichiometric conditions with no dilution air
from any source (including leaner than stoichiometric operation). BAR's exhaust dilution correction essentially
involves the application of a dilution factor to the concentrations measured at the tailpipe. As described in Sierra's SAE
paper, BAR's method is more sophisticated than the DF calculation incorporated into the FTP because it accounts for
variations in air-fuel ratio. However, the BAR procedure ignores the effects of background air, which is not a factor
during tailpipe measurements. As the SAE paper illustrates, Sierra's recommended DF equation incorporates the same
basic dilution correction used by BAR in combination with a correction for pollutants in the background air. When
correcting tailpipe concentrations for dilution, where no background air is involved, Sierra's DF calculation and BAR's
dilution adjustment produce the same result.
Recognizing the advantages of BAR's new dilution correction procedure, EPA has incorporated it in Guidance
to states on Acceleration Simulation Mode (ASM) testing. Although BAR's procedure is equally applicable to other
tests that rely on concentration measurement, it has not yet been incorporated into revised guidance for idle, 2500 rpm,
and other steady-state tests. However, when CVS testing is used in combination with Sierra's recommended reverse
dilution calculation procedure, the effect is similar to using BAR's dilution correction.
reduced by more than the true reduction in mass emissions.
With measurement systems that remove water, and for an engine running a stoichiometric, a 6% sum of CO and
CO2 represents each part exhaust being diluted with 1.5 parts air.
-------
Appendix F
Modal Analysis of Second-by-Second Data Preconditioning Guidelines
Developed by Sierra Research
Contract 68-C4-0056 Work Assignment 2-04
89
-------
Modal Analysis of Second-by-Second Data Preconditioning Guidelines
Developed by Sierra Research
Contract 68-C4-0056 Work Assignment 2-04
Using the replicate IM240 data collected by Gordon-Darby, it was possible, through trial and error, to identify criteria
to determine whether a vehicle failing an initial IM240 is inadequately preconditioned and should be tested again. This
analysis was performed for each pollutant individually, and then for all pollutants combined. The analysis included 283
LDVs and 83 LDTs. The evaluation followed a step-wise progression in which the aim was to maximize the identification
of vehicles that could benefit from a second test, while minimizing testing of vehicles likely to fail a second test.
Recommendations for passenger cars are summarized below. A similar set of conditions was also developed for light-duty
trucks, which are subject to different IM240 standards than passenger cars.
IM240 Retest Criteria for Passenger Cars
HC Failures - If PPmHC209-214 is less than 1,500, a retest is recommended if any of the following occur:
l.Phase2HC<0. 8 g/mi; or
2. massHCi75_i99 < 0.2 g; or
3. (ppmHC75-80/PpmHC2i4) > 4.0
For vehicles failing only HC, the following additional constraints are required for a vehicle to be retested:
1. Mass HCi75_i99<0.3g and (ppmHC75-80/PpmHC209-214)>i-5;or
2. Mass HCi75_i99 < 0.3g and Phase 2 HC < 1.0 g/mi
CO Failures - For CO failures, the above criteria for HC are recommended. In addition, the following constraints are
recommended:
1. do not retest if Phase 2 CO > 20 g/mi and (Phase 1 CO/Phase 2 CO) <2; and
2. if the vehicle fails both HC and CO, retest if Mass HCiys-igg <0.3 g and mass
C0i75_i99<5.0g.
If the vehicle is a CO-only failure, then a vehicle would benefit from a retest if:
1. Mass COi75_i99 < 6.0 g; or
2. (ppmCO75-80/PpmCO209-214) > 4.0; or
3. Mass COi75.i99 < 10 g and (Phase I CO > 0.75 x Phase 2 CO).
NOx Failures - For vehicles failing HC or CO and NOx, a retest is recommended if the following condition occurs:
1. Mass NOxi75_i99 = l.Og
90
-------
For NOx Only failures, retest is recommended if the following criteria are met:
1. Mass NOxi75i99<9; or
2. Mass NOxi75-i99l-5;or
3. IM240 NOx<2.2 and (ppmNOx40-45/ppmNOx209-215)> 1.0
Multiple Pollutants - For multiple pollutant failures, a retest is eliminated under the following conditions:
1. the vehicle fails for all pollutants; or
2. the vehicle fails HC and CO and (Phase 2 CO > 20 g/mi and mass COns-199 >6.0 g); or
3. the vehicle fails HC and NOx and (ppmHC209-214 >1,200) or (ppmNOx209-214 > 1,200
IM240 Retest Criteria for Light-Duty Trucks
Because they are subject to different numerical IM240 emission standards, a different set of retest criteria were
developed for light-duty trucks. These criteria are similar to those established for passenger cars, with adjustments to
account for standards differences.
HC Failures -For 1981 to 1983 model year vehicles, if ppmHC209-214 < 2,000 and any of the following conditions
exist, then a retest is recommended:
1. Phase 2 HC< 3.0 g/mi; or
2. Mass HCi75_i99 < 0.8 g; or
3. (ppmHC75-80/PpmHC209-214)>4.0
In addition, if the full IM240 is less than 3.5 g/mi HC (regardless of the value of ppmHC209-214X then a retest is
recommended.
For 1984 and later model year vehicles, if ppmHC209-2144.0
In addition, if 0.42.0 (regardless of the value of
ppmHC209-214) then a retest is recommended.
A retest is not recommended if Phase 2 HC > 3.2 g/mi.
CO Failures - For CO failures, the above criteria outlined for HC were also used. In addition, the following
conditions were also imposed to cut down on the number of vehicles incorrectly identified as needing a retest:
91
-------
1. If 1981 to 1983 model year and Mass COi75-i99>36g then do not retest.
2. If 1984 or later model year and Mass COi75_i99>18g then do not retest.
3. If Phase 2 CO>40 and Phase 2 CO > Phase I CO then do not retest.
NOx Failures - If the vehicle failed NOx and either HC or CO, the above criteria were used to determine the need
foraretest. ForLDTl&2s, if the vehicle failed only NOx. then a retest is recommended if Mass NOxi75_i 99 < 1.4
g. For 1988 and later LDT3&4s, a retest is recommended only if Mass NOxiys.igg < 2.5 g.
92
-------
Appendix G
Full and Fast-Pass IM240 Positive Kinetic Energy Speed Variation Limits
Developed by Sierra Research
Contract 68-C4-0056
93
-------
Full and Fast-Pass IM240 Positive Kinetic Energy Speed Variation Limits
Developed by Sierra Research
Contract 68-C4-0056
Evaluation of Alternative Statistical Measures
Based upon similar work conducted by the New York Automotive Emissions Laboratory (AEL,)7 two easily
determined, alternative statistical metrics were evaluated for their ability to identify and quantify IM240 speed variations that
significantly affect emissions:
(1). DPWRSUM - the sum of absolute changes in specific power; and
(2). Positive Kinetic Energy (PKE) - the sum of positive differences in kinetic energy per unit distance.
Each of these metrics are explained in more detail below.
DPWRSUM - Specific power is defined as power per unit mass, which can be restated as follows:
1 \M 2
.„. n power work Akinetic energy yXmassXAV
Specific Power = = = =
mass massxAtime massxAtime massxAtime
Over a transient driving cycle of second-by-second speeds, EPA defines the specific power P at any time t (and dropping the
factor of !/2) as:
Pt =Vt2 -Vt-12
The absolute difference in specific power at time t can then be written as:
DPt = Pt-Pt-i| =
Vt2 -2 Vt2! +Vt22
The DPWRSUM statistic then is defined over a cycle of N seconds as:
W. J. Webster and C. Shih, "A Statistically Derived Metric to Monitor Time-Speed Variability in Practical Emissions
Testing," New York State Department of Environmental Conservation, presented at the 6th CRC On-Road Vehicle
Emissions Workshop, March 18-20, 1996.
94
-------
DPWRSUM =
t=0 t=0
PKE - Positive Kinetic Energy has been defined mathematically as:
vt2-2Vt2.1+Vt2.2
PKE =
X
Jdx
0
over a traveled driving cycle of distance x where PP is the positive specific power and is given by the following expression
when Vt > Vt_j, and is zero when Vt < Vt_j.
PPt = Vt2 -Vt2.j
Each of these metrics can be easily computed from the second-by-second speed measurements collected in IM240
testing. In comparing their relative ability to identify speed variations that produce high emissions, it is helpful to consider
which speed variations contribute to the value of each metric (similar to the earlier examination of the SE statistic) over an
IM240 test.
Note that although both DPWRSUM and PKE are affected by differences in specific power or squared speeds over
"adjacent" seconds of an IM240 trace, the value of DPWRSUM is increased during decelerations as well as accelerations.
PKE on the other hand, is only increased during acceleration periods.
95
-------
IM240 REFERENCE
DATA
TIME
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
SPEED
0.0
0.0
0.0
0.0
0.0
3.0
5.9
8.6
11.5
14.3
16.9
17.3
18.1
20.7
21.7
22.4
22.5
22.1
21.5
20.9
20.4
19.8
17.0
14.9
14.9
15.2
15.5
16.0
17.1
19.1
21.1
22.7
22.9
22.7
22.6
21.3
19.0
17.1
CUM
PKE
(miles/hr2
)
0.0
0.0
0.0
0.0
0.0
10,800.0
14,080.4
15,214.6
16,417.2
17,001.5
17,079.7
13,902.5
12,336.8
13,263.7
12,284.1
11,261.4
9,964.5
8,890.2
8,046.4
7,366.6
6,805.5
6,336.9
5,983.3
5,704.2
5,450.1
5,306.1
5,171.6
5,103.3
5,213.3
5,599.3
5,990.0
6,242.3
6,014.8
5,745.3
5,500.0
5,287.2
5,110.8
4,961.9
PKE VARIATION CUTPOINTS (miles/hr2)
"BASE
TV
DELTA
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
342.3
356.7
343.7
328.3
314.3
302.2
292.1
283.6
MULT.
FACTO
R
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
4.000
3.986
3.971
3.957
3.943
3.929
3.914
3.900
VARYING
DELTA
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1,369.3
1,421.8
1,365.1
1,299.3
1,239.3
1,187.0
1,143.3
1,105.9
CUMULATIVE
PKE
LOW
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
4,621
4,820
4,650
4,446
4,261
4,100
3,968
3,856
HIGH
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
7,359
7,664
7,380
7,045
6,739
6,474
6,254
6,068
96
-------
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
15.8
15.8
17.7
19.8
21.6
23.2
24.2
24.6
24.9
25.0
25.7
26.1
26.7
27.5
28.6
29.3
29.8
30.1
30.4
30.7
30.7
30.5
30.4
30.3
30.4
30.8
30.4
29.9
29.5
29.8
30.3
30.7
30.9
31.0
30.9
30.4
29.8
29.9
30.2
30.7
31.2
31.8
32.2
4,831.8
4,708.3
4,937.5
5,220.8
5,450.3
5,638.2
5,685.3
5,592.5
5,481.7
5,332.7
5,321.5
5,245.9
5,216.3
5,230.2
5,307.9
5,298.0
5,246.1
5,155.0
5,068.3
4,985.6
4,848.3
4,719.2
4,597.2
4,481.7
4,389.2
4,352.1
4,250.1
4,154.4
4,064.1
4,022.9
4,013.3
3,988.8
3,935.5
3,869.4
3,791.8
3,718.5
3,649.2
3,595.5
3,569.2
3,569.2
3,569.3
3,582.2
3,569.2
276.1
269.1
282.2
298.4
311.5
322.2
324.9
319.6
313.3
304.8
304.1
299.8
298.1
298.9
303.3
302.8
299.8
294.6
289.6
284.9
277.1
269.7
262.7
256.1
250.8
248.7
242.9
237.4
232.3
229.9
229.3
228.0
224.9
221.1
216.7
212.5
208.5
205.5
204.0
204.0
204.0
204.7
204.0
3.886
3.871
3.857
3.843
3.829
3.814
3.800
3.786
3.771
3.757
3.743
3.729
3.714
3.700
3.686
3.671
3.657
3.643
3.629
3.614
3.600
3.586
3.571
3.557
3.543
3.529
3.514
3.500
3.486
3.471
3.457
3.443
3.429
3.414
3.400
3.386
3.371
3.357
3.343
3.329
3.314
3.300
3.286
1,072.9
1,041.7
1,088.4
1,146.5
1,192.5
1,229.0
1,234.6
1,209.9
1,181.5
1,145.0
1,138.2
1,117.8
1,107.2
1,105.9
1,118.0
1,111.6
1,096.4
1,073.2
1,051.0
1,029.8
997.5
967.0
938.3
911.1
888.7
877.6
853.6
831.0
809.6
798.1
792.9
784.8
771.1
755.0
736.8
719.5
703.1
689.8
681.9
678.9
676.0
675.6
670.2
3,759
3,667
3,849
4,074
4,258
4,409
4,451
4,383
4,300
4,188
4,183
4,128
4,109
4,124
4,190
4,186
4,150
4,082
4,017
3,956
3,851
3,752
3,659
3,571
3,501
3,474
3,397
3,323
3,255
3,225
3,220
3,204
3,164
3,114
3,055
2,999
2,946
2,906
2,887
2,890
2,893
2,907
2,899
5,905
5,750
6,026
6,367
6,643
6,867
6,920
6,802
6,663
6,478
6,460
6,364
6,323
6,336
6,426
6,410
6,343
6,228
6,119
6,015
5,846
5,686
5,535
5,393
5,278
5,230
5,104
4,985
4,874
4,821
4,806
4,774
4,707
4,624
4,529
4,438
4,352
4,285
4,251
4,248
4,245
4,258
4,239
97
-------
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
32.4
32.2
31.7
28.6
25.1
21.6
18.1
14.6
11.1
7.6
4.1
0.6
0.0
0.0
0.0
0.0
0.0
3.3
6.6
9.9
13.2
16.5
19.8
22.2
24.3
25.8
26.4
25.7
25.1
24.7
25.2
25.4
27.2
26.5
24.0
22.7
19.4
17.7
17.2
18.1
18.6
20.0
20.7
3,531.2
3,469.8
3,411.4
3,360.3
3,316.8
3,280.2
3,250.2
3,226.3
3,208.4
3,196.3
3,189.8
3,188.9
3,188.9
3,188.9
3,188.9
3,188.9
3,188.9
3,203.1
3,250.7
3,331.3
3,443.8
3,587.2
3,760.1
3,892.7
4,013.3
4,090.8
4,093.0
4,045.3
3,999.9
3,956.1
3,951.8
3,924.1
4,024.3
3,979.2
3,939.2
3,902.0
3,870.9
3,842.9
3,816.0
3,834.3
3,832.2
3,879.0
3,887.7
201.8
198.3
195.0
192.0
189.5
187.5
185.7
184.4
183.4
182.7
182.3
182.2
182.2
182.2
182.2
182.2
182.2
183.0
185.8
190.4
196.8
205.0
214.9
222.5
229.4
233.8
233.9
231.2
228.6
226.1
225.8
224.3
230.0
227.4
225.1
223.0
221.2
219.6
218.1
219.1
219.0
221.7
222.2
3.271
3.257
3.243
3.229
3.214
3.200
3.186
3.171
3.157
3.143
3.129
3.114
3.100
3.086
3.071
3.057
3.043
3.029
3.014
3.000
2.986
2.971
2.957
2.943
2.929
2.914
2.900
2.886
2.871
2.857
2.843
2.829
2.814
2.800
2.786
2.771
2.757
2.743
2.729
2.714
2.700
2.686
2.671
660.2
645.9
632.2
620.0
609.3
599.9
591.7
584.7
578.9
574.1
570.3
567.5
564.9
562.3
559.7
557.1
554.5
554.4
560.0
571.1
587.6
609.1
635.4
654.7
671.7
681.3
678.3
667.1
656.4
646.0
642.0
634.3
647.2
636.7
627.1
618.0
609.9
602.4
595.0
594.8
591.3
595.4
593.5
2,871
2,824
2,779
2,740
2,708
2,680
2,658
2,642
2,630
2,622
2,619
2,621
2,624
2,627
2,629
2,632
2,634
2,649
2,691
2,760
2,856
2,978
3,125
3,238
3,342
3,409
3,415
3,378
3,344
3,310
3,310
3,290
3,377
3,342
3,312
3,284
3,261
3,241
3,221
3,240
3,241
3,284
3,294
4,191
4,116
4,044
3,980
3,926
3,880
3,842
3,811
3,787
3,770
3,760
3,756
3,754
3,751
3,749
3,746
3,743
3,757
3,811
3,902
4,031
4,196
4,396
4,547
4,685
4,772
4,771
4,712
4,656
4,602
4,594
4,558
4,672
4,616
4,566
4,520
4,481
4,445
4,411
4,429
4,423
4,474
4,481
98
-------
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
21.7
22.4
22.5
22.1
21.5
20.9
20.4
19.8
17.0
17.1
15.8
15.8
17.7
19.8
21.6
22.2
24.5
24.7
24.8
24.7
24.6
24.6
25.1
25.6
25.7
25.4
24.9
25.0
25.4
26.0
26.0
25.7
26.1
26.7
27.3
30.5
33.5
36.2
37.3
39.3
40.5
42.1
43.5
3,914.4
3,923.5
3,895.8
3,863.1
3,831.7
3,801.8
3,772.9
3,745.4
3,722.1
3,703.4
3,682.2
3,661.2
3,720.0
3,794.6
3,860.2
3,863.3
3,964.6
3,943.1
3,915.9
3,883.2
3,851.1
3,819.6
3,817.5
3,815.4
3,789.6
3,758.6
3,728.8
3,704.9
3,698.2
3,702.8
3,673.1
3,644.1
3,637.9
3,643.0
3,648.1
3,812.6
3,978.0
4,133.0
4,172.3
4,282.5
4,330.6
4,412.1
4,477.8
223.7
224.2
222.6
220.8
219.0
217.3
215.6
214.0
212.7
211.6
210.4
209.2
212.6
216.9
220.6
220.8
226.6
225.3
223.8
221.9
220.1
218.3
218.2
218.0
216.6
214.8
213.1
211.7
211.3
211.6
209.9
208.3
207.9
208.2
208.5
217.9
227.3
236.2
238.4
244.7
247.5
252.1
255.9
2.657
2.643
2.629
2.614
2.600
2.586
2.571
2.557
2.543
2.529
2.514
2.500
2.486
2.471
2.457
2.443
2.429
2.414
2.400
2.386
2.371
2.357
2.343
2.329
2.314
2.300
2.286
2.271
2.257
2.243
2.229
2.214
2.200
2.186
2.171
2.157
2.143
2.129
2.114
2.100
2.086
2.071
2.057
594.4
592.6
585.2
577.1
569.3
561.8
554.4
547.3
540.9
535.1
529.1
523.1
528.4
535.9
542.1
539.3
550.2
544.0
537.1
529.4
521.9
514.5
511.1
507.7
501.2
494.0
487.1
480.9
477.0
474.6
467.8
461.1
457.4
455.0
452.7
470.0
487.1
502.8
504.1
513.9
516.2
522.3
526.4
3,320
3,331
3,311
3,286
3,262
3,240
3,219
3,198
3,181
3,168
3,153
3,138
3,192
3,259
3,318
3,324
3,414
3,399
3,379
3,354
3,329
3,305
3,306
3,308
3,288
3,265
3,242
3,224
3,221
3,228
3,205
3,183
3,181
3,188
3,195
3,343
3,491
3,630
3,668
3,769
3,814
3,890
3,951
4,509
4,516
4,481
4,440
4,401
4,364
4,327
4,293
4,263
4,239
4,211
4,184
4,248
4,330
4,402
4,403
4,515
4,487
4,453
4,413
4,373
4,334
4,329
4,323
4,291
4,253
4,216
4,186
4,175
4,177
4,141
4,105
4,095
4,098
4,101
4,283
4,465
4,636
4,676
4,796
4,847
4,934
5,004
99
-------
167
168
169
170
171
172
173
174
175
176
111
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
45.1
46.0
46.8
47.5
47.5
47.3
47.2
47.2
47.4
47.9
48.5
49.1
49.5
50.0
50.6
51.0
51.5
52.2
53.2
54.1
54.6
54.9
55.0
54.9
54.6
54.6
54.8
55.1
55.5
55.7
56.1
56.3
56.6
56.7
56.7
56.3
56.0
55.0
53.4
51.6
51.8
52.1
52.5
4,561.4
4,584.2
4,598.2
4,603.2
4,546.8
4,492.0
4,438.6
4,386.5
4,352.1
4,343.2
4,342.6
4,342.0
4,324.9
4,316.3
4,316.0
4,299.3
4,291.0
4,299.3
4,332.3
4,356.8
4,347.7
4,322.3
4,280.9
4,232.4
4,185.2
4,139.1
4,109.5
4,088.2
4,075.0
4,046.6
4,034.0
4,006.4
3,986.7
3,952.4
3,911.4
3,871.4
3,832.5
3,795.0
3,759.3
3,725.4
3,704.9
3,691.1
3,683.7
260.7
262.0
262.8
263.1
259.8
256.7
253.7
250.7
248.7
248.2
248.2
248.1
247.2
246.7
246.7
245.7
245.2
245.7
247.6
249.0
248.5
247.0
244.6
241.9
239.2
236.5
234.9
233.6
232.9
231.3
230.5
229.0
227.8
225.9
223.5
221.2
219.0
216.9
214.8
212.9
211.7
210.9
210.5
2.043
2.029
2.014
2.000
1.986
1.971
1.957
1.943
1.929
1.914
1.900
1.886
1.871
1.857
1.843
1.829
1.814
1.800
1.786
1.771
1.757
1.743
1.729
1.714
1.700
1.686
1.671
1.657
1.643
1.629
1.614
1.600
1.586
1.571
1.557
1.543
1.529
1.514
1.500
1.486
1.471
1.457
1.443
532.5
531.4
529.3
526.1
516.0
506.1
496.4
487.0
479.7
475.1
471.5
467.9
462.5
458.1
454.5
449.3
444.9
442.3
442.1
441.0
436.6
430.5
422.9
414.6
406.6
398.7
392.5
387.2
382.6
376.6
372.1
366.3
361.3
354.9
348.1
341.3
334.8
328.4
322.3
316.3
311.5
307.4
303.7
4,029
4,053
4,069
4,077
4,031
3,986
3,942
3,899
3,872
3,868
3,871
3,874
3,862
3,858
3,861
3,850
3,846
3,857
3,890
3,916
3,911
3,892
3,858
3,818
3,779
3,740
3,717
3,701
3,692
3,670
3,662
3,640
3,625
3,597
3,563
3,530
3,498
3,467
3,437
3,409
3,393
3,384
3,380
5,094
5,116
5,127
5,129
5,063
4,998
4,935
4,874
4,832
4,818
4,814
4,810
4,787
4,774
4,771
4,749
4,736
4,742
4,774
4,798
4,784
4,753
4,704
4,647
4,592
4,538
4,502
4,475
4,458
4,423
4,406
4,373
4,348
4,307
4,259
4,213
4,167
4,123
4,082
4,042
4,016
3,998
3,987
100
-------
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
53.0
53.5
54.0
54.9
55.4
55.6
56.0
56.0
55.8
55.2
54.5
53.6
52.5
51.5
50.5
48.0
44.5
41.0
37.5
34.0
30.5
27.0
23.5
20.0
16.5
13.0
9.5
6.0
2.5
0.0
Cycle Sums
3,682.8
3,682.0
3,681.1
3,705.8
3,704.7
3,684.4
3,677.1
3,644.6
3,612.7
3,581.7
3,551.6
3,522.5
3,494.5
3,467.4
3,441.2
3,416.8
3,394.4
3,374.0
3,355.6
3,339.0
3,324.3
3,311.4
3,300.3
3,290.9
3,283.1
3,277.1
3,272.7
3,269.9
3,268.7
3,268.7
3,268.7
210.5
210.4
210.4
211.8
211.7
210.6
210.1
208.3
206.5
204.7
203.0
201.3
199.7
198.2
196.7
195.3
194.0
192.8
191.8
190.8
190.0
189.2
188.6
188.1
187.6
187.3
187.0
186.9
186.8
186.8
1.429
1.414
1.400
1.386
1.371
1.357
1.343
1.329
1.314
1.300
1.286
1.271
1.257
1.243
1.229
1.214
1.200
1.186
1.171
1.157
1.143
1.129
1.114
1.100
1.086
1.071
1.057
1.043
1.029
1.014
300.7
297.6
294.5
293.5
290.4
285.8
282.2
276.7
271.3
266.1
261.0
255.9
251.1
246.3
241.6
237.1
232.8
228.6
224.6
220.8
217.1
213.6
210.2
206.9
203.7
200.7
197.7
194.9
192.1
189.5
3,382
3,384
3,387
3,412
3,414
3,399
3,395
3,368
3,341
3,316
3,291
3,267
3,243
3,221
3,200
3,180
3,162
3,145
3,131
3,118
3,107
3,098
3,090
3,084
3,079
3,076
3,075
3,075
3,077
3,079
3,079
3,984
3,980
3,976
3,999
3,995
3,970
3,959
3,921
3,884
3,848
3,813
3,778
3,746
3,714
3,683
3,654
3,627
3,603
3,580
3,560
3,541
3,525
3,510
3,498
3,487
3,478
3,470
3,465
3,461
3,458
3,458
101
-------
Appendix H
Derivation of TRLHP Coefficients
102
-------
Derivation of TRLHP Coefficients
(a) Road Load Equation
(1) Vehicle Loading. Road load is defined by the following equation relating track road load
horsepower and vehicle velocity.
TRLHPjg, Obmph = (Av * Obmph) + (By * Obmph2) + (CV* Cfcmi?)
Where: TRLHP = Track Road Load Horsepower.
Av, By, Cy = Coefficients relating TRLHP and velocity.
Obmph = Observed velocity in mph.
(2) Coefficients. Ay, By, and Cy are horsepower coefficients from EPA vehicle certification data
or EPA default values. Coefficients shall be calculated to a minimum of five significant digits
by the following equations. Power fractions determined from track coast-down data shall be
calculated to a minimum of two significant digits. In the absence of new car certification
coefficients, the default power fractions shall be used.
A PF
<£> Av=^^*(TRLHP@50mph) hp/mph
B PF
BV =^r*(TRLHP@50mph) hp/mph2
C PF
O C¥ = *(TRLHP50mph) hp/mph3
Where: Av, Bv, Cv = Coefficients relating TRLHP and velocity.
AyPF, ByPF, and CyPF are power fractions, and indicate the fraction of the
total power at 50 mph contributed by each of the Av*50, Bv*2500, and
5,000 terms.
TRLHP @50mph = Track Road Load Horsepower at 50mph.
(D) AyPF + ByPF + CyPF = 1
Derivation of AyPF, ByPF, and CyPF from known track coastdown curves shall be computed as
follows:
A*50
~
_
(Av*50)+(Bv*2500)+(Cv*125,000)
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B *2500
B PF =
(A ¥*50)+(B¥*2500)+(C¥* 125,000)
CPF __ C¥*125,000 _
(G) v (Av*50)+(B¥*2500)+(C¥*125,000)
Default values:
AVPF = 0.35
BVPF = 0.10
CyPF = 0.55
(3) TRLHP(gi5Qmp^ In absence of new vehicle certification data, the 50 mph TRLHP shall be
selected from the EPA I/M Look-up Table. It is based on the following equation:
/0.5*ETW/
I /3 2 2
TRLHP =
Where: ET = Elapsed time for the vehicle on the road to coast down from 55 to 45
mph
ETW = Equivalent Test Weight in pounds
Vj = Initial velocity in feet/second
¥2 = Final velocity in feet/second
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Appendix I
Derivation of CTRL Coefficients
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Derivation of Dynamometer Tire/Roll Interface Losses
(a) Generic Tire Roll Loss
(1) Tire/Roll Interface Losses. Tire/roll losses include vehicle drive train losses and may be
determined on a vehicle and dynamometer roll size specific basis, or using the default values
presented below.
Tire losses may be characterized on a vehicle and roll size specific basis by the following
equation:
GTRL@ Qbmph = (At * Obmph) + (Bt * Obmph2) + ©t * Obmph3)
Where: CTRL = Generic tire/roll interface losses, in horsepower.
At, Bt, Ct are coefficients derived by fitting a third order curve of tire losses,
in horsepower, and velocity.
Obmph is the observed velocity in mph.
hp/mph
hp/mph2
-0.09
50mph.8) hp/mph3
Where: At8, Bt8, Ct8 are coefficients relating tire losses, in horsepower, and velocity
on an 8.65 inch twin roll dynamometer.
0.76, 0.33, -0.09 are default 50 mph power fraction values derived from
experimental data.
GTRL@50mph_8 = -0.378193 + 0.0033207*DAXWT
DAXWT = (VAXF + VAXE)/2
VAXF = Drive axle weight for a vehicle with a full fuel tank from EPA
Certification database.
VAXE = Drive axle weight for a vehicle with an empty fuel tank from EPA
Certification database.
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0 65
— *(GTRL@50mph.20) hp/mph
50mph.20) hp/mph2
50mph.20) hp/mph3
Where: At20, Bt,20, Ct20 are coefficients relating tire losses, in horsepower, and
velocity on a 20 inch twin roll dynamometer.
0.65, 0.48, -0. 13 are default 50 mph power fraction values derived from
experimental data.
h_2Q = 0.241645 + 0.0020844*DAXWT
DAXWT = (VAXF + VAXE)/2
VAXF = Drive axle weight for a vehicle with a full fuel tank from EPA
Certification database.
VAXE = Drive axle weight for a vehicle with an empty fuel tank from EPA
Certification database.
(2) Look-up Table. The vehicle specific values for GTRL(g50mph.8 and GTRL(g50mph.20 using
default values for 50 mph power fractions are published in the latest version of the EPA I/M
Look-up Table.
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