Repeatability: Not required, but
                                recommended for initial installation.
                               Noise: Not required, but recommended for
                                initial installation.
Sec.   1065.307: Linearity     Speed: Upon initial installation, within
 verification.                  370 days before testing and after major
                                maintenance.
                               Torque: Upon initial installation, within
                                370 days before testing and after major
                                maintenance.
                               Electrical power: Upon initial
                                installation, within 370 days before
                                testing and after major maintenance.
                               Fuel flow rate: Upon initial
                                installation, within 370 days before
                                testing, and after major maintenance.
                               Intake-air, dilution air, diluted
                                exhaust, and batch sampler flow rates:
                                Upon initial installation, within 370
                                days before testing and after major
                                maintenance, unless flow is verified by
                                propane check or by carbon or oxygen
                                balance.
                               Raw exhaust flow rate: Upon initial
                                installation, within 185 days before
                                testing and after major maintenance,
                                unless flow is verified by propane check
                                or by carbon or oxygen balance.
                               Gas dividers: Upon initial installation,
                                within 370 days before testing, and
                                after major maintenance.
                               Gas analyzers (unless otherwise noted):
                                Upon initial installation, within 35
                                days before testing and after major
                                maintenance.
                               FTIR and photoacoustic analyzers: Upon
                                initial installation, within 370 days
                                before testing and after major
                                maintenance.
                               GC-ECD: Upon initial installation and
                                after major maintenance.
                               PM balance: Upon initial installation,
                                within 370 days before testing and after
                                major maintenance.
                               Pressure, temperature, and dewpoint: Upon
                                initial installation, within 370 days
                                before testing and after major
                                maintenance.
Sec.   1065.308: Continuous    Upon initial installation or after system
 gas analyzer system response   modification that would affect response.
 and updating-recording
 verification--for gas
 analyzers not continuously
 compensated for other gas
 species.
Sec.   1065.309: Continuous    Upon initial installation or after system
 gas analyzer system-response   modification that would affect response.
 and updating-recording
 verification--for gas
 analyzers continuously
 compensated for other gas
 species.
Sec.   1065.310: Torque......  Upon initial installation and after major
                                maintenance.
Sec.   1065.315: Pressure,     Upon initial installation and after major
 temperature, dewpoint.         maintenance.
Sec.   1065.320: Fuel flow...  Upon initial installation and after major
                                maintenance.
Sec.   1065.325: Intake flow.  Upon initial installation and after major
                                maintenance.
Sec.   1065.330: Exhaust flow  Upon initial installation and after major
                                maintenance.
Sec.   1065.340: Diluted       Upon initial installation and after major
 exhaust flow (CVS).            maintenance.
Sec.   1065.341: CVS and       Upon initial installation, within 35 days
 batch sampler verification     before testing, and after major
 \b\.                           maintenance.
Sec.   1065.342 Sample dryer   For thermal chillers: upon installation
 verification.                  and after major maintenance.
                               For osmotic membranes; upon installation,
                                within 35 days of testing, and after
                                major maintenance.
Sec.   1065.345: Vacuum leak.  For laboratory testing: upon initial
                                installation of the sampling system,
                                within 8 hours before the start of the
                                first test interval of each duty-cycle
                                sequence, and after maintenance such as
                                pre-filter changes.
                               For field testing: after each
                                installation of the sampling system on
                                the vehicle, prior to the start of the
                                field test, and after maintenance such
                                as pre-filter changes.
Sec.   1065.350: CO2 NDIR H2O  Upon initial installation and after major
 interference.                  maintenance.
Sec.   1065.355: CO NDIR CO2   Upon initial installation and after major
 and H2O interference.          maintenance.
Sec.   1065.360: FID           Calibrate all FID analyzers: upon initial
 calibrationn.                  installation and after major
                                maintenance.
THC FID optimization, and THC  Optimize and determine CH4 response for
 FID verification.              THC FID analyzers: upon initial
                                installation and after major
                                maintenance.
                               Verify CH4 response for THC FID
                                analyzers: upon initial installation,
                                within 185 days before testing, and
                                after major maintenance.
Sec.   1065.362: Raw exhaust   For all FID analyzers: upon initial
 FID O2 interference.           installation, and after major
                                maintenance.
                               For THC FID analyzers: upon initial
                                installation, after major maintenance,
                                and after FID optimization according to
                                Sec.   1065.360.
Sec.   1065.365: Nonmethane    Upon initial installation, within 185
 cutter penetration.            days before testing, and after major
                                maintenance.
Sec.   1065.370: CLD CO2 and   Upon initial installation and after major
 H2O quench.                    maintenance.
Sec.   1065.372: NDUV HC and   Upon initial installation and after major
 H2O interference.              maintenance.
Sec.   1065.375: N2O analyzer  Upon initial installation and after major
 interference.                  maintenance.
Sec.   1065.376: Chiller NO2   Upon initial installation and after major
 penetration.                   maintenance.
Sec.   1065.378: NO2-to-NO     Upon initial installation, within 35 days
 converter conversion.          before testing, and after major
                                maintenance.

Sec.   1065.390: PM balance    Independent verification: upon initial
 and weighing.                  installation, within 370 days before
                                testing, and after major maintenance.
                               Zero, span, and reference sample
                                verifications: within 12 hours of
                                weighing, and after major maintenance.
Sec.   1065.395: Inertial PM   Independent verification: upon initial
 balance and weighing.          installation, within 370 days before
                                testing, and after major maintenance.
                               Other verifications: upon initial
                                installation and after major
                                maintenance.
------------------------------------------------------------------------
\a\ Perform calibrations and verifications more frequently, according to
  measurement system manufacturer instructions and good engineering
  judgment.
\b\ The CVS verification described in Sec.   1065.341 is not required
  for systems that agree within 2% based on a chemical
  balance of carbon or oxygen of the intake air, fuel, and diluted
  exhaust.

0
59. Section 1065.307 is amended by revising paragraph (a) and Table 1
at the end of the section to read as follows:

Sec.  1065.307  Linearity verification.

    (a) Scope and frequency. Perform a linearity verification on each
measurement system listed in Table 1 of this section at least as
frequently as indicated in Table 1 of Sec.  1065.303, consistent with
measurement system manufacturer recommendations and good engineering
judgment. Note that this linearity verification may replace
requirements we previously referred to as ``calibrations''. The intent
of a linearity verification is to determine that a measurement system
responds proportionally over the measurement range of interest. A
linearity verification generally consists of introducing a series of at
least 10 reference values to a measurement system. The measurement
system quantifies each reference value. The measured values are then
collectively compared to the reference values by using a least squares
linear regression and the linearity criteria specified in Table 1 of
this section.
* * * * *

              Table 1 of Sec.   1065.307--Measurement Systems That Require Linearity Verifications
----------------------------------------------------------------------------------------------------------------
                                                                       Linearity criteria
                                               -----------------------------------------------------------------
       Measurement system           Quantity        [verbarlm]
                                                   xmin(a1-1)+a0         a1              SEE             r\2\
                                                    [verbarlm]
----------------------------------------------------------------------------------------------------------------
Speed...........................      [fnof]n   <= 0.05% [middot]     0.98-1.02  <= 2% [middot]         >= 0.990
                                                 [fnof]nmax                       [fnof]nmax
Torque..........................            T   <= 1% [middot]        0.98-1.02  <= 2% [middot]         >= 0.990
                                                 Tmax.                            Tmax.
Electrical power................            P   <= 1% [middot]        0.98-1.02  <= 2% [middot]         >= 0.990
                                                 Pmax.                            Pmax.
Fuel flow rate..................           mb   <= 1% [middot]        0.98-1.02  <= 2% [middot]         >= 0.990
                                                 mbmax.                           mbmax
Intake-air flow rate............           nb   <= 1% [middot]        0.98-1.02  <= 2% [middot]         >= 0.990
                                                 nbmax.                           nbmax.
Dilution air flow rate..........           nb   <= 1% [middot]        0.98-1.02  <= 2% [middot]         >= 0.990
                                                 nbmax.                           nbmax.
Diluted exhaust flow rate.......           nb   <= 1% [middot]        0.98-1.02  <= 2% [middot]         >= 0.990
                                                 nbmax.                           nbmax.
Raw exhaust flow rate...........           nb   <= 1% [middot]        0.98-1.02  <= 2% [middot]         >= 0.990
                                                 nbmax.                           nbmax.
Batch sampler flow rates........           nb   <= 1% [middot]        0.98-1.02  <= 2% [middot]         >= 0.990
                                                 nbmax.                           nbmax.
Gas dividers....................      x/xspan   <= 0.5% [middot]      0.98-1.02  <= 2% [middot]         >= 0.990
                                                 xmax/xspan                       xmax/xspan
Gas analyzers for laboratory                x   <= 0.5% [middot]      0.99-1.01  <= 1% [middot]         >= 0.998
 testing.                                        xbmax.                           xbmax.
Gas analyzers for field testing.            x   <= 1% [middot]        0.99-1.01  <= 1% [middot]         >= 0.998
                                                 xbmax.                           xbmax.
PM balance......................            m   <= 1% [middot]        0.99-1.01  <= 1% [middot]         >= 0.998
                                                 mmax.                            mbmax.
Pressures.......................            p   <= 1% [middot]        0.99-1.01  <= 1% [middot]         >= 0.998
                                                 pbmax.                           pbmax.
Dewpoint for intake air, PM-             Tdew   <= 0.5% [middot]      0.99-1.01  <= 0.5% [middot]       >= 0.998
 stabilization and balance                       Tdewmax                          Tdewmax
 environments.
Other dewpoint measurements.....         Tdew   <= 1% [middot]        0.99-1.01  <= 1% [middot]         >= 0.998
                                                 Tdewmax                          Tdewmax
Analog-to-digital conversion of             T   <= 1% [middot]        0.99-1.01  <= 1% [middot]         >= 0.998
 temperature signals.                            Tbmax                            Tmax
----------------------------------------------------------------------------------------------------------------

0
60. Section 1065.340 is amended by revising paragraphs (a) through (g),
adding paragraph (h), and adding and reserving paragraph (i) before
Figure 1 to read as follows:

Sec.  1065.340  Diluted exhaust flow (CVS) calibration.

    (a) Overview. This section describes how to calibrate flow meters
for diluted exhaust constant-volume sampling (CVS) systems.
    (b) Scope and frequency. Perform this calibration while the flow
meter is installed in its permanent position, except as allowed in
paragraph (c) of this section. Perform this calibration after you
change any part of the flow configuration upstream or downstream of the
flow meter that may affect the flow-meter calibration. Perform this
calibration upon initial CVS installation and whenever corrective
action does not resolve a failure to meet the diluted exhaust flow
verification (i.e., propane check) in Sec.  1065.341.
    (c) Ex-situ CFV and SSV calibration. You may remove a CFV or SSV
from its permanent position for calibration as long as it meets the
following requirements when installed in the CVS:
    (1) Upon installation of the CFV or SSV into the CVS, use good
engineering judgment to verify that you have not introduced any leaks
between the CVS inlet and the venturi.
    (2) After ex-situ venturi calibration, you must verify all venturi
flow combinations for CFVs or at minimum of 10 flow points for an SSV
using the propane check as described in Sec.  1065.341. Your propane
check result for each venturi flow point may not exceed the tolerance
in Sec.  1065.341(f)(5).
    (3) To verify your ex-situ calibration for a CVS with more than a
single CFV, perform the following check to verify that there are no
flow meter entrance effects that can prevent you from passing this
verification.

    (i) Use a constant flow device like a CFO kit to deliver a constant
flow of propane to the dilution tunnel.
    (ii) Measure hydrocarbon concentrations at a minimum of 10 separate
flow rates for an SSV flow meter, or at all possible flow combinations
for a CFV flow meter, while keeping the flow of propane constant. We
recommend selecting CVS flow rates in a random order.
    (iii) Measure the concentration of hydrocarbon background in the
dilution air at the beginning and end of this test. Subtract the
average background concentration from each measurement at each flow
point before performing the regression analysis in paragraph (c)(3)(iv)
of this section.
    (iv) Perform a power regression using all the paired values of flow
rate and corrected concentration to obtain a relationship in the form
of y = a [middot] x \b\. Use concentration as the independent variable
and flow rate as the dependent variable. For each data point, calculate
the difference between the measured flow rate and the value represented
by the curve fit. The difference at each point must be less than 1% of the appropriate regression value. The value of b must be
between -1.005 and -0.995. If your results do not meet these limits,
take corrective action consistent with Sec.  1065.341(a).
    (d) Reference flow meter. Calibrate a CVS flow meter using a
reference flow meter such as a subsonic venturi flow meter, a long-
radius ASME/NIST flow nozzle, a smooth approach orifice, a laminar flow
element, a set of critical flow venturis, or an ultrasonic flow meter.
Use a reference flow meter that reports quantities that are NIST-
traceable within 1% uncertainty. Use this reference flow
meter's response to flow as the reference value for CVS flow-meter
calibration.
    (e) Configuration. Do not use an upstream screen or other
restriction that could affect the flow ahead of the reference flow
meter, unless the flow meter has been calibrated with such a
restriction.
    (f) PDP calibration. Calibrate a positive-displacement pump (PDP)
to determine a flow-versus-PDP speed equation that accounts for flow
leakage across sealing surfaces in the PDP as a function of PDP inlet
pressure. Determine unique equation coefficients for each speed at
which you operate the PDP. Calibrate a PDP flow meter as follows:
    (1) Connect the system as shown in Figure 1 of this section.
    (2) Leaks between the calibration flow meter and the PDP must be
less than 0.3% of the total flow at the lowest calibrated flow point;
for example, at the highest restriction and lowest PDP-speed point.
    (3) While the PDP operates, maintain a constant temperature at the
PDP inlet within 2% of the mean absolute inlet temperature,
Tin.
    (4) Set the PDP speed to the first speed point at which you intend
to calibrate.
    (5) Set the variable restrictor to its wide-open position.
    (6) Operate the PDP for at least 3 min to stabilize the system.
Continue operating the PDP and record the mean values of at least 30
seconds of sampled data of each of the following quantities:
    (i) The mean flow rate of the reference flow meter,
nref. This may include several measurements of different
quantities, such as reference meter pressures and temperatures, for
calculating nref.
    (ii) The mean temperature at the PDP inlet, Tin.
    (iii) The mean static absolute pressure at the PDP inlet,
pin.
    (iv) The mean static absolute pressure at the PDP outlet,
pout.
    HERE
    (v) The mean PDP speed, fnPDP.
    HERE
    (7) Incrementally close the restrictor valve to decrease the
absolute pressure at the inlet to the PDP, pin.
    (8) Repeat the steps in paragraphs (e)(6) and (7) of this section
to record data at a minimum of six restrictor positions ranging from
the wide open restrictor position to the minimum expected pressure at
the PDP inlet.
    (9) Calibrate the PDP by using the collected data and the equations
in Sec.  1065.640.
    (10) Repeat the steps in paragraphs (e)(6) through (9) of this
section for each speed at which you operate the PDP.
    (11) Use the equations in Sec.  1065.642 to determine the PDP flow
equation for emission testing.
    (12) Verify the calibration by performing a CVS verification (i.e.,
propane check) as described in Sec.  1065.341.
    (13) Do not use the PDP below the lowest inlet pressure tested
during calibration.
    (g) CFV calibration. Calibrate a critical-flow venturi (CFV) to
verify its discharge coefficient, Cd, at the lowest expected
static differential pressure between the CFV inlet and outlet.
Calibrate a CFV flow meter as follows:
    (1) Connect the system as shown in Figure 1 of this section.
    (2) Verify that any leaks between the calibration flow meter and
the CFV are less than 0.3% of the total flow at the highest
restriction.
    (3) Start the blower downstream of the CFV.
    (4) While the CFV operates, maintain a constant temperature at the
CFV inlet within 2% of the mean absolute inlet temperature,
Tin.
    (5) Set the variable restrictor to its wide-open position. Instead
of a variable restrictor, you may alternately vary the pressure
downstream of the CFV by varying blower speed or by introducing a
controlled leak. Note that some blowers have limitations on nonloaded
conditions.
    (6) Operate the CFV for at least 3 min to stabilize the system.
Continue operating the CFV and record the mean values of at least 30
seconds of sampled data of each of the following quantities:
    (i) The mean flow rate of the reference flow meter,
nref. This may include several measurements of different
quantities, such as reference meter pressures and temperatures, for
calculating nref.
    (ii) The mean dewpoint of the calibration air, Tdew. See
Sec.  1065.640 for permissible assumptions during emission
measurements.
    (iii) The mean temperature at the venturi inlet, Tin.
    (iv) The mean static absolute pressure at the venturi inlet,
pin.
    (v) The mean static differential pressure between the CFV inlet and
the CFV outlet, [Delta]pCFV.
    (7) Incrementally close the restrictor valve or decrease the
downstream pressure to decrease the differential pressure across the
CFV, [Delta]pCFV.
    (8) Repeat the steps in paragraphs (f)(6) and (7) of this section
to record mean data at a minimum of ten restrictor positions, such that
you test the fullest practical range of [Delta]pCFV expected
during testing. We do not require that you remove calibration
components or CVS components to calibrate at the lowest possible
restrictions.
    (9) Determine Cd and the lowest allowable pressure
ratio, r, according to Sec.  1065.640.
    (10) Use Cd to determine CFV flow during an emission
test. Do not use the CFV below the lowest allowed r, as determined in
Sec.  1065.640.
    (11) Verify the calibration by performing a CVS verification (i.e.,
propane check) as described in Sec.  1065.341.
    (12) If your CVS is configured to operate more than one CFV at a
time in parallel, calibrate your CVS by one of the following:
    (i) Calibrate every combination of CFVs according to this section
and Sec.  1065.640. Refer to Sec.  1065.642 for

instructions on calculating flow rates for this option.
    (ii) Calibrate each CFV according to this section and Sec.
1065.640. Refer to Sec.  1065.642 for instructions on calculating flow
rates for this option.
    (h) SSV calibration. Calibrate a subsonic venturi (SSV) to
determine its calibration coefficient, Cd, for the expected
range of inlet pressures. Calibrate an SSV flow meter as follows:
    (1) Connect the system as shown in Figure 1 of this section.
    (2) Verify that any leaks between the calibration flow meter and
the SSV are less than 0.3% of the total flow at the highest
restriction.
    (3) Start the blower downstream of the SSV.
    (4) While the SSV operates, maintain a constant temperature at the
SSV inlet within 2% of the mean absolute inlet temperature,
Tin.
    (5) Set the variable restrictor or variable-speed blower to a flow
rate greater than the greatest flow rate expected during testing. You
may not extrapolate flow rates beyond calibrated values, so we
recommend that you make sure the Reynolds number, Re#, at the SSV
throat at the greatest calibrated flow rate is greater than the maximum
Re# expected during testing.
    (6) Operate the SSV for at least 3 min to stabilize the system.
Continue operating the SSV and record the mean of at least 30 seconds
of sampled data of each of the following quantities:
    (i) The mean flow rate of the reference flow meter nref.
This may include several measurements of different quantities, such as
reference meter pressures and temperatures, for calculating
nref.
    (ii) Optionally, the mean dewpoint of the calibration air,
Tdew. See Sec.  1065.640 for permissible assumptions.
    (iii) The mean temperature at the venturi inlet, Tin.
    (iv) The mean static absolute pressure at the venturi inlet,
pin.
    (v) Static differential pressure between the static pressure at the
venturi inlet and the static pressure at the venturi throat,
[Delta]pssv.
    (7) Incrementally close the restrictor valve or decrease the blower
speed to decrease the flow rate.
    (8) Repeat the steps in paragraphs (g)(6) and (7) of this section
to record data at a minimum of ten flow rates.
    (9) Determine a functional form of Cd versus Re# by
using the collected data and the equations in Sec.  1065.640.
    (10) Verify the calibration by performing a CVS verification (i.e.,
propane check) as described in Sec.  1065.341 using the new
Cd versus Re# equation.
    (11) Use the SSV only between the minimum and maximum calibrated
flow rates.
    (12) Use the equations in Sec.  1065.642 to determine SSV flow
during a test.
    (i) Ultrasonic flow meter calibration. [Reserved]
* * * * *

0
61. Section 1065.341 is amended by revising paragraphs (a)(5), (a)(6),
and (f)(5) and adding paragraph (a)(7) to read as follows:

Sec.  1065.341  CVS and batch sampler verification (propane check).

    (a) * * *
    (5) Change in CVS calibration. Perform a calibration of the CVS
flow meter as described in Sec.  1065.340.
    (6) Flow meter entrance effects. Inspect the CVS tunnel to
determine whether the entrance effects from the piping configuration
upstream of the flow meter adversely affect the flow measurement.
    (7) Other problems with the CVS or sampling verification hardware
or software. Inspect the CVS system, CVS verification hardware, and
software for discrepancies.
* * * * *
    (f) * * *
    (5) Subtract the reference C3H8 mass from the
calculated mass. If this difference is within 2% of the
reference mass, the CVS passes this verification. If not, take
corrective action as described in paragraph (a) of this section.
* * * * *

0
62. Section 1065.350 is amended by revising paragraph (d)(7) to read as
follows:

Sec.  1065.350  H2O interference verification for CO2 NDIR analyzers.

* * * * *
    (d) * * *
    (7) While the analyzer measures the sample's concentration, record
30 seconds of sampled data. Calculate the arithmetic mean of this data.
The analyzer meets the interference verification if this value is
within (0.0  0.4) mmol/mol.
* * * * *

0
63. Section 1065.360 is amended by revising paragraph (e) introductory
text to read as follows:

Sec.  1065.360  FID optimization and verification.

* * * * *
    (e) THC FID methane (CH4) response verification. This procedure is
only for FID analyzers that measure THC. If the value of
RFCH4[THC-FID] from paragraph (d) of this section is within
5% of its most recent previously determined value, the THC
FID passes the methane response verification. For example, if the most
recent previous value for RFCH4[THC-FID] was 1.05 and it
changed by 0.05 to become 1.10 or it changed by -0.05 to
become 1.00, either case would be acceptable because 4.8%
is less than 5%. Verify RFCH4[THC-FID] as
follows:
* * * * *

0
64. Section 1065.370 is amended by revising paragraph (g)(1) to read as
follows:

Sec.  1065.370  CLD CO2 and H2O quench verification.

* * * * *
    (g) * * *
    (1) You may omit this verification if you can show by engineering
analysis that for your NOX sampling system and your emission
calculation procedures, the combined CO2 and H2O
interference for your NOX CLD analyzer always affects your
brake-specific NOX emission results within no more than
1% of the applicable NOX standard. If you
certify to a combined emission standard (such as a NOX +
NMHC standard), scale your NOX results to the combined
standard based on the measured results (after incorporating
deterioration factors, if applicable). For example, if your final
NOX + NMHC value is half of the emission standard, double
the NOX result to estimate the level of NOX
emissions corresponding to the applicable standard.
* * * * *

0
65. Section 1065.372 is amended by revising paragraph (e)(1) to read as
follows:

Sec.  1065.372  NDUV analyzer HC and H2O interference verification.

* * * * *
    (e) * * *
    (1) You may omit this verification if you can show by engineering
analysis that for your NOX sampling system and your emission
calculation procedures, the combined HC and H2O interference
for your NOX NDUV analyzer always affects your brake-
specific NOX emission results by less than 0.5% of the
applicable NOX standard.
* * * * *

0
66. Section 1065.378 is amended by revising paragraph (d)(3)(iv) to
read as follows:

Sec.  1065.378  NO2-to-NO converter conversion verification.

* * * * *
    (d) * * *
    (3) * * *
    (iv) Switch the ozonator on and adjust the ozone generation rate so
the NO

measured by the analyzer is 20 percent of xNOref or a value
which would simulate the maximum concentration of NO2
expected during testing, while maintaining at least 10 percent
unreacted NO. This ensures that the ozonator is generating
NO2 at the maximum concentration expected during testing.
Record the concentration of NO by calculating the mean of 30 seconds of
sampled data from the analyzer and record this value as
xNOmeas.
* * * * *

Subpart F--[Amended]

0
67. Section 1065.510 is amended as follows:
0
a. By revising paragraphs (a) introductory text, (b)(5)(i), and (b)(6).
0
b. By adding paragraph (b)(7).
0
c. By revising paragraphs (c)(2), (d)(5), (f)(3), (f)(5), and (g).
0
d. By adding paragraphs (c)(4) and (h) to read as follows:

Sec.  1065.510  Engine mapping.

    (a) Applicability, scope, and frequency. An engine map is a data
set that consists of a series of paired data points that represent the
maximum brake torque versus engine speed, measured at the engine's
primary output shaft. Map your engine if the standard-setting part
requires engine mapping to generate a duty cycle for your engine
configuration. Map your engine while it is connected to a dynamometer
or other device that can absorb work output from the engine's primary
output shaft according to Sec.  1065.110. To establish speed and torque
values for mapping, we generally recommend that you stabilize an engine
for at least 15 seconds at each setpoint and record the mean feedback
speed and torque of the last (4 to 6) seconds. Configure any auxiliary
work inputs and outputs such as hybrid, turbo-compounding, or
thermoelectric systems to represent their in-use configurations, and
use the same configuration for emission testing. See Figure 1 of Sec.
1065.210. This may involve configuring initial states of charge and
rates and times of auxiliary-work inputs and outputs. We recommend that
you contact the Designated Compliance Officer before testing to
determine how you should configure any auxiliary-work inputs and
outputs. Use the most recent engine map to transform a normalized duty
cycle from the standard-setting part to a reference duty cycle specific
to your engine. Normalized duty cycles are specified in the standard-
setting part. You may update an engine map at any time by repeating the
engine-mapping procedure. You must map or re-map an engine before a
test if any of the following apply:
* * * * *
    (b) * * *
    (5) * * *
    (i) For any engine subject only to steady-state duty cycles, you
may perform an engine map by using discrete speeds. Select at least 20
evenly spaced setpoints from 95% of warm idle speed to the highest
speed above maximum power at which 50% of maximum power occurs. We
refer to this 50% speed as the check point speed as described in
paragraph (b)(5)(iii) of this section. At each setpoint, stabilize
speed and allow torque to stabilize. Record the mean speed and torque
at each setpoint. Use linear interpolation to determine intermediate
speeds and torques. Use this series of speeds and torques to generate
the power map as described in paragraph (e) of this section.
* * * * *
    (6) Use one of the following methods to determine warm high-idle
speed for engines with a high-speed governor if they are subject to
transient testing with a duty cycle that includes reference speed
values above 100%:
    (i) You may use a manufacturer-declared warm high-idle speed if the
engine is electronically governed. For engines with a high-speed
governor that shuts off torque output at a manufacturer-specified speed
and reactivates at a lower manufacturer-specified speed (such as
engines that use ignition cut-off for governing), declare the middle of
the specified speed range as the warm high-idle speed.
    (ii) Measure the warm high-idle speed using the following
procedure:
    (A) Set operator demand to maximum and use the dynamometer to
target zero torque on the engine's primary output shaft. If the mean
feedback torque is within 1% of Tmax mapped, you
may use the observed mean feedback speed at that point as the measured
warm high-idle speed.
    (B) If the engine is unstable as a result of in-use production
components (such as engines that use ignition cut-off for governing, as
opposed to unstable dynamometer operation), you must use the mean
feedback speed from paragraph (b)(6)(ii)(A) of this section as the
measured warm high-idle speed. The engine is considered unstable if any
of the 1 Hz speed feedback values are not within 2% of the
calculated mean feedback speed. We recommend that you determine the
mean as the value representing the midpoint between the observed
maximum and minimum recorded feedback speed.
    (C) If your dynamometer is not capable of achieving a mean feedback
torque within 1% of Tmax mapped, operate the
engine at a second point with operator demand set to maximum with the
dynamometer set to target a torque equal to the recorded mean feedback
torque on the previous point plus 20% of Tmax mapped. Use
this data point and the data point from paragraph (b)(6)(ii)(A) of this
section to extrapolate the engine speed where torque is equal to zero.
    (D) You may use a manufacturer-declared Tmax instead of
the measured Tmax mapped. If you do this, or if you are able
to determine mean feedback speed as described in paragraphs
(b)(6)(ii)(A) and (B) of this section, you may measure the warm high-
idle speed before running the speed sweep specified in paragraph (b)(5)
of this section.
    (7) For engines with a low-speed governor, if a nonzero idle torque
is representative of in-use operation, operate the engine at warm idle
with the manufacturer-declared idle torque. Set the operator demand to
minimum, use the dynamometer to target the declared idle torque, and
allow the engine to govern the speed. Measure this speed and use it as
the warm idle speed for cycle generation in Sec.  1065.512. We
recommend recording at least 30 values of speed and using the mean of
those values. If you identify multiple warm idle torques under
paragraph (f)(4)(i) of this section, measure the warm idle speed at
each torque. You may map the idle governor at multiple load levels and
use this map to determine the measured warm idle speed at the declared
idle torque(s).
    (c) * * *
    (2) Map the amount of negative torque required to motor the engine
by repeating paragraph (b) of this section with minimum operator
demand. You may start the negative torque map at either the minimum or
maximum speed from paragraph (b) of this section.
* * * * *
    (4) For engines with an electric hybrid system, you may create a
negative torque map that would include the full negative torque of the
electric hybrid system, so operator demand will be at a minimum when
the reference duty cycle specifies negative torque values.
    (d) * * *
    (5) Perform one of the following:
    (i) For constant-speed engines subject only to steady-state
testing, you may perform an engine map by using a series of discrete
torques. Select at least five evenly spaced torque setpoints from no-

load to 80% of the manufacturer-declared test torque or to a torque
derived from your published maximum power level if the declared test
torque is unavailable. Starting at the 80% torque point, select
setpoints in 2.5% intervals, stopping at the endpoint torque. The
endpoint torque is defined as the first discrete mapped torque value
greater than the torque at maximum observed power where the engine
outputs 90% of the maximum observed power; or the torque when engine
stall has been determined using good engineering judgment (i.e. sudden
deceleration of engine speed while adding torque). You may continue
mapping at higher torque setpoints. At each setpoint, allow torque and
speed to stabilize. Record the mean feedback speed and torque at each
setpoint. From this series of mean feedback speed and torque values,
use linear interpolation to determine intermediate values. Use this
series of mean feedback speeds and torques to generate the power map as
described in paragraph (e) of this section.
    (ii) For any constant-speed engine, you may perform an engine map
with a continuous torque sweep by continuing to record the mean
feedback speed and torque at 1 Hz or more frequently. Use the
dynamometer to increase torque. Increase the reference torque at a
constant rate from no-load to the endpoint torque as defined in
paragraph (d)(5)(i) of this section. You may continue mapping at higher
torque setpoints. Unless the standard-setting part specifies otherwise,
target a torque sweep rate equal to the manufacturer-declared test
torque (or a torque derived from your published power level if the
declared test torque is not known) divided by 180 s. Stop recording
after you complete the sweep. Verify that the average torque sweep rate
over the entire map is within 7% of the target torque sweep
rate. Use linear interpolation to determine intermediate values from
this series of mean feedback speed and torque values. Use this series
of mean feedback speeds and torques to generate the power map as
described in paragraph (e) of this section.
    (iii) For electric power generation applications in which normal
engine operation is limited to a specific speed range, map the engine
with two points as described in this paragraph (d)(5)(iii). After
stabilizing at the no-load governed speed in paragraph (d)(4) of this
section, record the mean feedback speed and torque. Continue to operate
the engine with the governor or simulated governor controlling engine
speed using operator demand, and control the dynamometer to target a
speed of 97.5% of the recorded mean no-load governed speed. If the in-
use performance class of the electric power generation application is
known, you may use those values in place of 97.5% (e.g., for ISO 8528-5
G3 Performance Class, the steady-state frequency band is less than or
equal to 0.5%, so use 99.75% instead of 97.5%). Allow speed and torque
to stabilize. Record the mean feedback speed and torque. Record the
target speed. The absolute value of the speed error (the mean feedback
speed minus the target speed) must be no greater than 20% of the
difference between the recorded mean no-load governed speed and the
target speed. From this series of two mean feedback speed and torque
values, use linear interpolation to determine intermediate values. Use
this series of two mean feedback speeds and torques to generate a power
map as described in paragraph (e) of this section. Note that the
measured maximum test torque determined in Sec.  1065.610(b)(1), will
be the mean feedback torque recorded on the second point.
* * * * *
    (f) * * *
    (3) Optional declared speeds. You may use declared speeds instead
of measured speeds as follows:
    (i) You may use a declared value for maximum test speed for
variable-speed engines if it is within (97.5 to 102.5) % of the
corresponding measured value. You may use a higher declared speed if
the length of the ``vector'' at the declared speed is within 2% of the
length of the ``vector'' at the measured value. The term vector refers
to the square root of the sum of normalized engine speed squared and
the normalized full-load power (at that speed) squared, consistent with
the calculations in Sec.  1065.610.
    (ii) You may use a declared value for intermediate, ``A'', ``B'',
or ``C'' speeds for steady-state tests if the declared value is within
(97.5 to 102.5)% of the corresponding measured value.
    (iii) For electronically governed engines, you may use a declared
warm high-idle speed for calculating the alternate maximum test speed
as specified in Sec.  1065.610.
* * * * *
    (5) Optional declared torques. (i) For variable-speed engines you
may declare a maximum torque over the engine operating range. You may
use the declared value for measuring warm high-idle speed as specified
in this section.
    (ii) For constant-speed engines you may declare a maximum test
torque. You may use the declared value for cycle generation if it is
within (95 to 100) % of the measured value.
    (g) Mapping variable-speed engines with an electric hybrid system.
Map variable-speed engines that include electric hybrid systems as
described in this paragraph (g). You may ask to apply these provisions
to other types of hybrid engines, consistent with good engineering
judgment. However, do not use this procedure for engines used in hybrid
vehicles where the hybrid system is certified as part of the vehicle
rather than the engine. Follow the steps for mapping a variable-speed
engine as given in paragraph (b)(5) of this section except as noted in
this paragraph (g). You must generate one engine map with the hybrid
system inactive as described in paragraph (g)(1) of this section, and a
separate map with the hybrid system active as described in paragraph
(g)(2) of this section. See the standard-setting part to determine how
to use these maps. The map with the system inactive is typically used
to generate steady-state duty cycles, but may also be used to generate
transient cycles, such as those that do not involve engine motoring.
This hybrid-inactive map is also used for generating the hybrid-active
map. The hybrid-active map is typically used to generate transient duty
cycles that involve engine motoring.
    (1) Prepare the engine for mapping by either deactivating the
hybrid system or by operating the engine as specified in paragraph
(b)(4) of this section and remaining at this condition until the
rechargeable energy storage system (RESS) is depleted. Once the hybrid
has been disabled or the RESS is depleted, perform an engine map as
specified in paragraph (b)(5) of this section. If the RESS was depleted
instead of deactivated, ensure that instantaneous power from the RESS
remains less than 2% of the instantaneous measured power from the
engine (or engine-hybrid system) at all engine speeds.
    (2) The purpose of the mapping procedure in this paragraph (g) is
to determine the maximum torque available at each speed, such as what
might occur during transient operation with a fully charged RESS. Use
one of the following methods to generate a hybrid-active map:
    (i) Perform an engine map by using a series of continuous sweeps to
cover the engine's full range of operating speeds. Prepare the engine
for hybrid-active mapping by ensuring that the RESS state of charge is
representative of normal operation. Perform the sweep as specified in
paragraph (b)(5)(ii) of this section, but stop the sweep to charge the
RESS when the power measured from the RESS drops below the expected

maximum power from the RESS by more than 2% of total system power
(including engine and RESS power). Unless good engineering judgment
indicates otherwise, assume that the expected maximum power from the
RESS is equal to the measured RESS power at the start of the sweep
segment. For example, if the 3-second rolling average of total engine-
RESS power is 200 kW and the power from the RESS at the beginning of
the sweep segment is 50 kW, once the power from the RESS reaches 46 kW,
stop the sweep to charge the RESS. Note that this assumption is not
valid where the hybrid motor is torque-limited. Calculate total system
power as a 3-second rolling average of instantaneous total system
power. After each charging event, stabilize the engine for 15 seconds
at the speed at which you ended the previous segment with operator
demand set to maximum before continuing the sweep from that speed.
Repeat the cycle of charging, mapping, and recharging until you have
completed the engine map. You may shut down the system or include other
operation between segments to be consistent with the intent of this
paragraph (g)(2)(i). For example, for systems in which continuous
charging and discharging can overheat batteries to an extent that
affects performance, you may operate the engine at zero power from the
RESS for enough time after the system is recharged to allow the
batteries to cool. Use good engineering judgment to smooth the torque
curve to eliminate discontinuities between map intervals.
    (ii) Perform an engine map by using discrete speeds. Select map
setpoints at intervals defined by the ranges of engine speed being
mapped. From 95% of warm idle speed to 90% of the expected maximum test
speed, select setpoints that result in a minimum of 13 equally spaced
speed setpoints. From 90% to 110% of expected maximum test speed,
select setpoints in equally spaced intervals that are nominally 2% of
expected maximum test speed. Above 110% of expected maximum test speed,
select setpoints based on the same speed intervals used for mapping
from 95% warm idle speed to 90% maximum test speed. You may stop
mapping at the highest speed above maximum power at which 50% of
maximum power occurs. We refer to the speed at 50% power as the check
point speed as described in paragraph (b)(5)(iii) of this section.
Stabilize engine speed at each setpoint, targeting a torque value at
70% of peak torque at that speed without hybrid-assist. Make sure the
engine is fully warmed up and the RESS state of charge is within the
normal operating range. Snap the operator demand to maximum, operate
the engine there for at least 10 seconds, and record the 3-second
rolling average feedback speed and torque at 1 Hz or higher. Record the
peak 3-second average torque and 3-second average speed at that point.
Use linear interpolation to determine intermediate speeds and torques.
Follow Sec.  1065.610(a) to calculate the maximum test speed. Verify
that the measured maximum test speed falls in the range from 92 to 108%
of the estimated maximum test speed. If the measured maximum test speed
does not fall in this range, rerun the map using the measured value of
maximum test speed.
    (h) Other mapping procedures. You may use other mapping procedures
if you believe the procedures specified in this section are unsafe or
unrepresentative for your engine. Any alternate techniques you use must
satisfy the intent of the specified mapping procedures, which is to
determine the maximum available torque at all engine speeds that occur
during a duty cycle. Identify any deviations from this section's
mapping procedures when you submit data to us.

0
68. Section 1065.514 is amended by revising paragraph (f)(3) to read as
follows:

Sec.  1065.514  Cycle-validation criteria for operation over specified
duty cycles.

* * * * *
    (f) * * *
    (3) For discrete-mode steady-state testing, apply cycle-validation
criteria by treating the sampling periods from the series of test modes
as a continuous sampling period, analogous to ramped-modal testing and
apply statistical criteria as described in paragraph (f)(1) or (f)(2)
of this section. Note that if the gaseous and particulate test
intervals are different periods of time, separate validations are
required for the gaseous and particulate test intervals. Table 2
follows:

               Table 2 of Sec.   1065.514--Default Statistical Criteria for Validating Duty Cycles
----------------------------------------------------------------------------------------------------------------
              Parameter                         Speed                    Torque                   Power
----------------------------------------------------------------------------------------------------------------
Slope, a1............................  0.950 <= a1 <= 1.030...  0.830 <= a1 <= 1.030...  0.830 <= a1 <= 1.030.
Absolute value of intercept,           <= 10% of warm idle....  <= 2% of maximum mapped  <= 2% of maximum mapped
 [verbar]a0[verbar].                                             torque.                  power.
Standard error of estimate, SEE......  <= 5% of maximum test    <= 10% of maximum        <= 10% of maximum
                                        speed.                   mapped torque.           mapped power.
Coefficient of determination, r2.....  >= 0.970...............  >= 0.850...............  >= 0.910.
----------------------------------------------------------------------------------------------------------------

0
69. Section 1065.520 is amended by revising paragraph (g) introductory
text, (g)(5)(i), (g)(7), and (g)(8) and adding paragraph (g)(9) to read
as follows:

Sec.  1065.520  Pre-test verification procedures and pre-test data
collection.

* * * * *
    (g) Verify the amount of nonmethane hydrocarbon contamination in
the exhaust and background HC sampling systems within 8 hours before
the start of the first test interval of each duty-cycle sequence for
laboratory tests. You may verify the contamination of a background HC
sampling system by reading the last bag fill and purge using zero gas.
For any NMHC measurement system that involves separately measuring
methane and subtracting it from a THC measurement or for any
CH4 measurement system that uses an NMC, verify the amount
of THC contamination using only the THC analyzer response. There is no
need to operate any separate methane analyzer for this verification;
however, you may measure and correct for THC contamination in the
CH4 sample train for the cases where NMHC is determined by
subtracting CH4 from THC or, where CH4 is
determined, using an NMC as configured in Sec.  1065.365(d), (e), and
(f); and using the calculations in Sec.  1065.660(b)(2). Perform this
verification as follows:
* * * * *
    (5) * * *
    (i) For continuous sampling, record the mean THC concentration as
overflow zero gas flows.
* * * * *
    (7) You may correct the measured initial THC concentration for
drift as follows:
    (i) For batch and continuous HC analyzers, after determining the
initial THC concentration, flow zero gas to the analyzer zero or sample
port. When the

analyzer reading is stable, record the mean analyzer value.
    (ii) Flow span gas to the analyzer span or sample port. When the
analyzer reading is stable, record the mean analyzer value.
    (iii) Use mean analyzer values from paragraphs (g)(2), (g)(3),
(g)(7)(i), and (g)(7)(ii) of this section to correct the initial THC
concentration recorded in paragraph (g)(6) of this section for drift,
as described in Sec.  1065.550.
    (8) If any of the xTHC[THC-FID]init values exceed the
greatest of the following values, determine the source of the
contamination and take corrective action, such as purging the system
during an additional preconditioning cycle or replacing contaminated
portions:
    (i) 2% of the flow-weighted mean wet, net concentration expected at
the HC (THC or NMHC) standard.
    (ii) 2% of the flow-weighted mean wet, net concentration of HC (THC
or NMHC) measured during testing.
    (iii) 2 [mu]mol/mol.
    (9) If corrective action does not resolve the deficiency, you may
request to use the contaminated system as an alternate procedure under
Sec.  1065.10.
* * * * *

0
70. Section 1065.525 is amended by removing paragraph (c)(4) and
revising paragraph (a) to read as follows.

Sec.  1065.525  Engine starting, restarting, and shutdown.

    (a) For test intervals that require emission sampling during engine
starting, start the engine using one of the following methods:
    (1) Start the engine as recommended in the owners manual using a
production starter motor or air-start system and either an adequately
charged battery, a suitable power supply, or a suitable compressed air
source.
    (2) Use the dynamometer to start the engine. To do this, motor the
engine within  25% of its typical in-use cranking speed.
Stop cranking within 1 second of starting the engine.
    (3) In the case of hybrid engines, activate the system such that
the engine will start when its control algorithms determine that the
engine should provide power instead of or in addition to power from the
RESS. Unless we specify otherwise, engine starting throughout this part
generally refers to this step of activating the system on hybrid
engines, whether or not that causes the engine to start running.
* * * * *

0
71. Section 1065.530 is amended by revising paragraph (b)(13) to read
as follows:

Sec.  1065.530  Emission test sequence.

* * * * *
    (b) * * *
    (13) Drain any accumulated condensate from the intake air system
before starting a duty cycle, as described in Sec.  1065.125(e)(1). If
engine and aftertreatment preconditioning cycles are run before the
duty cycle, treat the preconditioning cycles and any associated soak
period as part of the duty cycle for the purpose of opening drains and
draining condensate. Note that you must close any intake air condensate
drains that are not representative of those normally open during in-use
operation.
* * * * *

0
72. Section 1065.546 is amended by revising paragraph (a) to read as
follows:

Sec.  1065.546  Validation of minimum dilution ratio for PM batch
sampling, and drift correction.

* * * * *
    (a) Determine minimum dilution ratio based on molar flow data. This
involves determination of at least two of the following three
quantities: Raw exhaust flow (or previously diluted flow), dilution air
flow, and dilute exhaust flow. You may determine the raw exhaust flow
rate based on the measured intake air or fuel flow rate and the raw
exhaust chemical balance terms as given in Sec.  1065.655(e). You may
determine the raw exhaust flow rate based on the measured intake air
and dilute exhaust molar flow rates and the dilute exhaust chemical
balance terms as given in Sec.  1065.655(f). You may alternatively
estimate the molar raw exhaust flow rate based on intake air, fuel rate
measurements, and fuel properties, consistent with good engineering
judgment.
* * * * *

0
73. Section 1065.550 is amended by revising the section heading and
paragraph (b) to read as follows:

Sec.  1065.550  Gas analyzer range validation and drift validation.

* * * * *
    (b) Drift validation and drift correction. Gas analyzer drift
validation is required for all gaseous exhaust constituents for which
an emission standard applies. It is also required for CO2
even if there is no CO2 emission standard. It is not
required for other gaseous exhaust constituents for which only a
reporting requirement applies (such as CH4 and
N2O).
    (1) Validate drift using one of the following methods:
    (i) For regulated exhaust constituents determined from the mass of
a single component, perform drift validation based on the regulated
constituent. For example, when NOX mass is determined with a
dry sample measured with a CLD and the removed water is corrected based
on measured CO2, CO, THC, and NOX concentrations,
you must validate the calculated NOX value.
    (ii) For regulated exhaust constituents determined from the masses
of multiple subcomponents, perform the drift validation based on either
the regulated constituent or all the mass subcomponents. For example,
when NOX is measured with separate NO and NO2
analyzers, you must validate either the NOX value or both
the NO and NO2 values.
    (iii) For regulated exhaust constituents determined from the
concentrations of multiple gaseous emission subcomponents prior to
performing mass calculations, perform drift validation on the regulated
constituent. You may not validate the concentration subcomponents
(e.g., THC and CH4 for NMHC) separately. For example, for
NMHC measurements, perform drift validation on NMHC; do not validate
THC and CH4 separately.
    (2) Drift validation requires two sets of emission calculations.
For each set of calculations, include all the constituents in the drift
validation. Calculate one set using the data before drift correction
and calculate the other set after correcting all the data for drift
according to Sec.  1065.672. Note that for purposes of drift
validation, you must leave unaltered any negative emission results over
a given test interval (i.e., do not set them to zero). These unaltered
results are used when validating either test interval results or
composite brake-specific emissions over the entire duty cycle for
drift. For each constituent to be validated, both sets of calculations
must include the following:
    (i) Calculated mass (or mass rate) emission values over each test
interval.
    (ii) If you are validating each test interval based on brake-
specific values, calculate brake-specific emission values over each
test interval.
    (iii) If you are validating over the entire duty cycle, calculate
composite brake-specific emission values.
    (3) The duty cycle is validated for drift if you satisfy the
following criteria:
    (i) For each regulated gaseous exhaust constituent, you must
satisfy one of the following:
    (A) For each test interval of the duty cycle, the difference
between the uncorrected and the corrected brake-specific emission
values of the regulated constituent must be within  4% of
the uncorrected value or the applicable emissions standard, whichever
is

greater. Alternatively, the difference between the uncorrected and the
corrected emission mass (or mass rate) values of the regulated
constituent must be within  4% of the uncorrected value or
the composite work (or power) multiplied by the applicable emissions
standard, whichever is greater. For purposes of validating each test
interval, you may use either the reference or actual composite work (or
power).
    (B) For each test interval of the duty cycle and for each
subcomponent of the regulated constituent, the difference between the
uncorrected and the corrected brake-specific emission values must be
within  4% of the uncorrected value. Alternatively, the
difference between the uncorrected and the corrected emissions mass (or
mass rate) values must be within  4% of the uncorrected
value.
    (C) For the entire duty cycle, the difference between the
uncorrected and the corrected composite brake-specific emission values
of the regulated constituent must be within  4% of the
uncorrected value or applicable emission standard, whichever is
greater.
    (D) For the entire duty cycle and for each subcomponent of the
regulated constituent, the difference between the uncorrected and the
corrected composite brake-specific emission values must be within
 4% of the uncorrected value.
    (ii) Where no emission standard applies for CO2, you
must satisfy one of the following:
    (A) For each test interval of the duty cycle, the difference
between the uncorrected and the corrected brake-specific CO2
values must be within  4% of the uncorrected value; or the
difference between the uncorrected and the corrected CO2
mass (or mass rate) values must be within  4% of the
uncorrected value.
    (B) For the entire duty cycle, the difference between the
uncorrected and the corrected composite brake-specific CO2
values must be within  4% of the uncorrected value.
    (4) If the test is not validated for drift as described in
paragraph (b)(1) of this section, you may consider the test results for
the duty cycle to be valid only if, using good engineering judgment,
the observed drift does not affect your ability to demonstrate
compliance with the applicable emission standards. For example, if the
drift-corrected value is less than the standard by at least two times
the absolute difference between the uncorrected and corrected values,
you may consider the data to be valid for demonstrating compliance with
the applicable standard.

Subpart G--[Amended]

0
74. Section 1065.602 is amended by revising paragraph (f)(3)
introductory text, (h), and (l)(1) to read as follows:

Sec.  1065.602  Statistics.

* * * * *
    (f) * * *
    (3) Use Table 1 of this section to compare t to the
tcrit values tabulated versus the number of degrees of
freedom. If t is less than tcrit, then t passes the t-test.
The Microsoft Excel software has a TINV function that returns
equivalent results and may be used in place of Table 1, which follows:
* * * * *
    (h) Slope. Calculate a least-squares regression slope,
a1y, as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.021

Example:

N = 6000
y1 = 2045.8
y = 1050.1
yref 1 = 2045.0
yref = 1055.3
[GRAPHIC] [TIFF OMITTED] TR15SE11.022

a1y = 1.0110
* * * * *
    (l) * * *
    (1) To estimate the flow-weighted mean raw exhaust NOX
concentration from a turbocharged heavy-duty compression-ignition
engine at a NOX standard of 2.5 g/(kW[middot]hr), you may do
the following:
    (i) Based on your engine design, approximate a map of maximum
torque versus speed and use it with the applicable normalized duty
cycle in the standard-setting part to generate a reference duty cycle
as described in Sec.  1065.610. Calculate the total reference work,
Wref, as described in Sec.  1065.650. Divide the reference
work by the duty cycle's time interval, [Delta]tdutycycle,
to determine mean reference power, Pref.
    (ii) Based on your engine design, estimate maximum power,
Pmax, the design speed at maximum power, fnmax,
the design maximum intake manifold boost pressure, pinmax,
and temperature, Tinmax. Also, estimate a mean fraction of
power that is lost due to friction and pumping, Pfrict. Use
this information along with the engine displacement volume,
Vdisp, an approximate volumetric efficiency,
[eta]V, and the number of engine strokes per power stroke
(2-stroke or 4-stroke), Nstroke, to estimate the maximum raw
exhaust molar flow rate, nehmax.
    (iii) Use your estimated values as described in the following
example calculation:

[GRAPHIC] [TIFF OMITTED] TR15SE11.023

Example:

eNOx = 2.5 g/(kW[middot]hr)
Wref = 11.883 kW[middot]hr
MNOx = 46.0055 g/mol = 46.0055[middot]10-\6\
g/[mu]mol
[Delta]tdutycycle = 20 min = 1200 s
Pref = 35.65 kW
Pfrict = 15%
Pmax = 125 kW
pmax = 300 kPa = 300,000 Pa
Vdisp = 3.0 l = 0.0030 m\3\/r
fnmax = 2,800 r/min = 46.67 r/s
Nstroke = 4
[eta]V = 0.9
R = 8.314472 J/(mol[middot]K)
Tmax = 348.15 K
[GRAPHIC] [TIFF OMITTED] TR15SE11.024

nexhmax = 6.53 mol/s
[GRAPHIC] [TIFF OMITTED] TR15SE11.025

xexp = 189.4 [micro]mol/mol
* * * * *

0
75. Section 1065.610 is amended by revising paragraphs (a), (b)(1), and
(c) to read as follows:

Sec.  1065.610  Duty cycle generation.

* * * * *
    (a) Maximum test speed, fntest. This section generally
applies to duty cycles for variable-speed engines. For constant-speed
engines subject to duty cycles that specify normalized speed commands,
use the no-load governed speed as the measured fntest. This
is the highest engine speed where an engine outputs zero torque. For
variable-speed engines, determine the measured fntest from
the power-versus-speed map, generated according to Sec.  1065.510, as
follows:
    (1) Based on the map, determine maximum power, Pmax, and
the speed at which maximum power occurred, fnPmax. If
maximum power occurs at multiple speeds, take fnPmax as the
lowest of these speeds. Divide every recorded power by Pmax
and divide every recorded speed by fnPmax. The result is a
normalized power-versus-speed map. Your measured fntest is
the speed at which the sum of the squares of normalized speed and power
is maximum. Note that if multiple maximum values are found,
fntest should be taken as the lowest speed of all points
with the same maximum sum of squares. Determine fntest as
follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.026

Where:

    fntest = maximum test speed.
    i = an indexing variable that represents one recorded value of
an engine map.
    fnnormi = an engine speed normalized by dividing it
by fnPmax.
    Pnormi = an engine power normalized by dividing it by
Pmax.

    Example:

(fnnorm1 = 1.002, Pnorm1 = 0.978, fn1
= 2359.71)
(fnnorm2 = 1.004, Pnorm2 = 0.977, fn2
= 2364.42)
(fnnorm3 = 1.006, Pnorm3 = 0.974, fn3
= 2369.13)
(fnnorm1\2\ + Pnorm1\2\) = (1.002\2\ + 0.978\2\)
= 1.960
(fnnorm2\2\ + Pnorm2\2\) = (1.004\2\ + 0.977\2\)
= 1.963
(fnnorm3\2\ + Pnorm3\2\) = (1.006\2\ + 0.974\2\)
= 1.961
maximum = 1.963 at-i = 2
    fntest = 2,364.42 r/min

    (2) For engines with a high-speed governor that will be subject to
a reference duty cycle that specifies normalized speeds greater than
100%, calculate an alternate maximum test speed, fntest,alt,
as specified in this paragraph (a)(2). If fntest,alt is less
than the measured maximum test speed, fntest, determined in
paragraph (a)(1) of this section, replace fntest with
fntest,alt. In this case, fntest,alt becomes the
``maximum test speed'' for that engine. Note that Sec.  1065.510 allows
you to apply an optional declared maximum test speed to the final
measured maximum test speed determined as an outcome of the comparison
between fntest, and fntest,alt in this paragraph
(a)(2). Determine fntest,alt as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.027

Where:

fntest,alt = alternate maximum test speed
fnhi,idle = warm high-idle speed
fnidle = warm idle speed
% speedmax = maximum normalized speed from duty cycle

    Example:
fnhi,idle = 2,200 r/min
fnidle = 800 r/min
% speedmax = 105% (Nonroad CI Transient Cycle)
fntest,alt = (2,200-800)/105% + 800
fntest,alt = 2,133 r/min

    (3) For variable-speed engines, transform normalized speeds to
reference speeds according to paragraph (c) of this section by using
the measured maximum test speed determined according to paragraphs
(a)(1) and (2) of this section--or use your declared maximum test
speed, as allowed in Sec.  1065.510.
    (4) For constant-speed engines, transform normalized speeds to
reference speeds according to paragraph (c) of this section by using
the measured no-load governed speed--or use your declared maximum test
speed, as allowed in Sec.  1065.510.
    (b) * * *
    (1) Based on the map, determine maximum power, Pmax, and
the speed at which maximum power occurs, fnPmax. If maximum
power occurs at multiple speeds, take fnPmax as the lowest
of these speeds. Divide every recorded power by Pmax and
divide every recorded speed by fnPmax. The result is a
normalized power-versus-speed map. Your measured Ttest is
the torque at which the sum of the squares of normalized speed and
power is maximum. Note that that if multiple maximum values are found,
Ttest should be taken as the highest torque of all points
with the same maximum sum of squares. Determine Ttest as
follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.028

Where:

    Ttest = maximum test torque.

    Example:

(fnnorm1 = 1.002, Pnorm1 = 0.978, T1 =
722.62 N[middot]m)
(fnnorm2 = 1.004, Pnorm2 = 0.977, T2 =
720.44 N[middot]m)
(fnnorm3 = 1.006, Pnorm3 = 0.974, T3 =
716.80 N[middot]m)
(fnnorm1\2\ + Pnorm1\2\) = (1.002\2\ + 0.978\2\)
= 1.960
(fnnorm1\2\ + Pnorm1\2\) = (1.004\2\ + 0.977\2\)
= 1.963
(fnnorm1\2\ + Pnorm1\2\) = (1.006\2\ + 0.974\2\)
= 1.961
maximum = 1.963 at--i = 2
Ttest-- = 720.44 N[middot]m
* * * * *
    (c) Generating reference speed values from normalized duty cycle
speeds. Transform normalized speed values to reference values as
follows:
    (1) % speed. If your normalized duty cycle specifies % speed
values, use your warm idle speed and your maximum test speed to
transform the duty cycle, as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.029

    Example:

% speed = 85%
fntest = 2,364 r/min
fnidle = 650 r/min
fnref = 85% [middot] (2,364 - 650) + 650
fnref = 2,107 r/min

    (2) A, B, and C speeds. If your normalized duty cycle specifies
speeds as A, B, or C values, use your power-versus-speed curve to
determine the lowest speed below maximum power at which 50% of maximum
power occurs. Denote this value as nlo. Take nlo
to be warm idle speed if all power points at speeds below the maximum
power speed are higher than 50% of maximum power. Also determine the
highest speed above maximum power at which 70% of maximum power occurs.
Denote this value as nhi. If all power points at speeds
above the maximum power speed are higher than 70% of maximum power,
take nhi to be the declared maximum safe engine speed or the
declared maximum representative engine speed, whichever is lower. Use
nhi and nlo to calculate reference values for A,
B, or C speeds as follows:

[GRAPHIC] [TIFF OMITTED] TR15SE11.030

    Example:

nlo = 1005 r/min
nhi = 2385 r/min
fnrefA = 0.25 [middot] (2385 - 1005) + 1005
fnrefB = 0.50 [middot] (2385 - 1005) + 1005
fnrefC = 0.75 [middot] (2385 - 1005) + 1005
fnrefA = 1350 r/min
fnrefB = 1695 r/min
fnrefC = 2040 r/min

    (3) Intermediate speed. If your normalized duty cycle specifies a
speed as ``intermediate speed,'' use your torque-versus-speed curve to
determine the speed at which maximum torque occurs. This is peak torque
speed. If maximum torque occurs in a flat region of the torque-versus-
speed curve, your peak torque speed is the midpoint between the lowest
and highest speeds at which the trace reaches the flat region. For
purposes of this paragraph (c)(3), a flat region is one in which
measured torque values are within 2% of the maximum recorded value.
Identify your reference intermediate speed as one of the following
values:
* * * * *

0
76. Section 1065.640 is amended by revising paragraphs (b)(1), (b)(2),
(b)(5), (e)(3), (e)(4), and (e)(7) to read as follows:

Sec.  1065.640  Flow meter calibration calculations.

* * * * *
    (b) * * *
    (1) PDP volume pumped per revolution, Vrev (m\3\/r):
    [GRAPHIC] [TIFF OMITTED] TR15SE11.031

    Example:

n&ref = 25.096 mol/s
R = 8.314472 J/(mol [middot] K)
Tin = 299.5 K
Pin = 98290 Pa
fnPDP = 1205.1 r/min = 20.085 r/s
[GRAPHIC] [TIFF OMITTED] TR15SE11.032

Vrev = 0.03166 m\3\/r
    (2) PDP slip correction factor, Ks (s/r):
    [GRAPHIC] [TIFF OMITTED] TR15SE11.033

    Example:

fnPDP = 1205.1 r/min = 20.085 r/s
Pout = 100.103 kPa
Pin = 98.290 kPa
[GRAPHIC] [TIFF OMITTED] TR15SE11.034

Ks = 0.006700 s/r
* * * * *
    (5) The following example illustrates these calculations:

       Table 1 of Sec.   1065.640--Example of PDP Calibration Data
------------------------------------------------------------------------
                                                    a1 (m\3\/  a0 (m\3\/
                  f8nPDP (r/min)                       min)        r)
------------------------------------------------------------------------
755.0.............................................      50.43      0.056
987.6.............................................      49.86     -0.013
1254.5............................................      48.54      0.028
1401.3............................................      47.30     -0.061
------------------------------------------------------------------------

* * * * *
    (e) * * *
    (3) If the standard deviation of all the Cd values is
less than or equal to 0.3% of the mean Cd, use the mean
Cd in Eq 1065.642-6, and use the CFV only up to the highest
r measured during calibration using the following equation:

[GRAPHIC] [TIFF OMITTED] TR15SE11.035

Where:

    [Delta]p--CFV = Differential static pressure; venturi
inlet minus venturi outlet.

    (4) If the standard deviation of all the Cd values
exceeds 0.3% of the mean Cd, omit the Cd values
corresponding to the data point collected at the highest r measured
during calibration.
* * * * *
    (7) If the standard deviation of the remaining Cd values
is less than or equal to 0.3% of the mean of the remaining
Cd, use that mean Cd in Eq 1065.642-6, and use
the CFV values only up to the highest r associated with the remaining
Cd.
* * * * *

0
77. Section 1065.642 is amended by revising paragraph (a) to read as
follows:

Sec.  1065.642  SSV, CFV, and PDP molar flow rate calculations.

* * * * *
    (a) PDP molar flow rate. Based upon the speed at which you operate
the PDP for a test interval, select the corresponding slope,
a1, and intercept, a0, as calculated in Sec.
1065.640, to calculate molar flow rate, n as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.036

Where:

[GRAPHIC] [TIFF OMITTED] TR15SE11.037

    Example:

a1 = 50.43 (m\3\/min) = 0.8405 (m\3\/s)
fnPDP = 755.0 r/min = 12.58 r/s
pout = 99950 Pa
pin = 98575 Pa
a0 = 0.056 (m\3\/r)
R = 8.314472 J/(mol[middot]K)
Tin = 323.5 K
Cp = 1000 (J/m\3\)/kPa
Ct = 60 s/min
[GRAPHIC] [TIFF OMITTED] TR15SE11.038

Vrev = 0.06383 m\3\/r
[GRAPHIC] [TIFF OMITTED] TR15SE11.039

n = 29.428 mol/s
* * * * *

0
78. Section 1065.645 is amended by revising the introductory text and
paragraph (a) to read as follows:

Sec.  1065.645  Amount of water in an ideal gas.

    This section describes how to determine the amount of water in an
ideal gas, which you need for various performance verifications and
emission calculations. Use the equation for the vapor pressure of water
in paragraph (a) of this section or another appropriate equation and,
depending on whether you measure dewpoint or relative humidity, perform
one of the calculations in paragraph (b) or (c) of this section. The
equations for the vapor pressure of water as presented in this section
are derived from equations in ``Saturation Pressure of Water on the New
Kelvin Temperature Scale'' (Goff, J.A., Transactions American Society
of Heating and Air-Conditioning Engineers, Vol. 63, No. 1607, pages
347-354). Note that the equations were originally published to derive
vapor pressure in units of atmospheres and have been modified to derive
results in units of kPa by converting the last term in each equation.
    (a) Vapor pressure of water. Calculate the vapor pressure of water
for a given saturation temperature condition, Tsat, as
follows, or use good engineering judgment to use a different
relationship of the vapor pressure of water to a given saturation
temperature condition:
(1) For humidity measurements made at ambient temperatures from (0 to
100) [deg]C, or for humidity measurements made over super-cooled water
at ambient temperatures from (-50 to 0) [deg]C, use the following
equation:

[GRAPHIC] [TIFF OMITTED] TR15SE11.040

Where:

pH20 = vapor pressure of water at saturation temperature
condition, kPa.
Tsat = saturation temperature of water at measured
conditions, K.
    Example:

Tsat = 9.5 [deg]C
Tsat = 9.5 + 273.15 = 282.65 K
[GRAPHIC] [TIFF OMITTED] TR15SE11.041

log10(pH20) = 0.074297
pH20 = 10\0.074297\ = 1.186581 kPa

    (2) For humidity measurements over ice at ambient temperatures from
(-100 to 0) [deg]C, use the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.042

    Example:

Tice = -15.4 [deg]C
Tice = -15.4 + 273.15 = 257.75 K
[GRAPHIC] [TIFF OMITTED] TR15SE11.043

log10(pH20) = -0.798207
pH20 = 10 -0.79821 = 0.159145 kPa
* * * * *

0
79. Section 1065.650 is amended as follows:
0
a. By revising paragraphs (c) introductory text, (c)(1), and (c)(4).
0
b. By adding paragraph (c)(5).
0
c. By revising paragraphs (d)(7), (e)(4), and (f)(4).

Sec.  1065.650  Emission calculations.

* * * * *
    (c) Total mass of emissions over a test interval. To calculate the
total mass of an emission, multiply a concentration by its respective
flow. For all systems, make preliminary calculations as described in
paragraph (c)(1) of this section to correct concentrations. Next, use
the method in paragraphs (c)(2) through (4) of this section that is
appropriate for your system. Finally, if necessary, calculate the mass
of NMHC as described in paragraph (c)(5) of this section for all
systems. Calculate the total mass of emissions as follows:
    (1) Concentration corrections. Perform the following sequence of
preliminary calculations on recorded concentrations:
    (i) Correct all gaseous emission analyzer concentration readings,
including continuous readings, sample bag readings, and dilution air
background readings, for drift as described in Sec.  1065.672. Note
that you must omit this step where brake-specific emissions are
calculated without the drift correction for performing the drift
validation according to Sec.  1065.550(b). When applying the initial
THC and CH4 contamination readings according to Sec.
1065.520(g), use the same values for both sets of calculations. You may
also use as-measured values in the initial set of calculations and
corrected values in the drift-corrected set of calculations as
described in Sec.  1065.520(g)(7).

    (ii) Correct all THC and CH4 concentrations, including
continuous readings, sample bags readings, and dilution air background
readings, for initial contamination, as described in Sec.  1065.660(a).
    (iii) Correct all concentrations measured on a ``dry'' basis to a
``wet'' basis, including dilution air background concentrations, as
described in Sec.  1065.659.
    (iv) Calculate all NMHC and CH4 concentrations,
including dilution air background concentrations, as described in Sec.
1065.660.
    (v) For emission testing with an oxygenated fuel, calculate any HC
concentrations, including dilution air background concentrations, as
described in Sec.  1065.665. See subpart I of this part for testing
with oxygenated fuels.
    (vi) Correct all the NOX concentrations, including
dilution air background concentrations, for intake-air humidity as
described in Sec.  1065.670.
* * * * *
    (4) Additional provisions for diluted exhaust sampling; continuous
or batch. The following additional provisions apply for sampling
emissions from diluted exhaust:
    (i) For sampling with a constant dilution ratio, DR, of diluted
exhaust versus exhaust flow (e.g., secondary dilution for PM sampling),
calculate m using the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.044

    Example:

mPMdil = 6.853 g
DR = 6:1
mPM = 6.853 [middot] 6
mPM = 41.118 g
    (ii) For continuous or batch sampling, you may measure background
emissions in the dilution air. You may then subtract the measured
background emissions, as described in Sec.  1065.667.
    (5) Mass of NMHC. Compare the corrected mass of NMHC to corrected
mass of THC. If the corrected mass of NMHC is greater than 0.98 times
the corrected mass of THC, take the corrected mass of NMHC to be 0.98
times the corrected mass of THC. If you omit the NMHC calculations as
described in Sec.  1065.660(b)(1), take the corrected mass of NMHC to
be 0.98 times the corrected mass of THC.
    (d) * * *
    (7) Integrate the resulting values for power over the test
interval. Calculate total work as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.045

Where:

W = total work from the primary output shaft.
Pi = instantaneous power from the primary output shaft
over an interval i.
[GRAPHIC] [TIFF OMITTED] TR15SE11.046

    Example:

N = 9000
[fnof]n1 = 1800.2 r/min
[fnof]n2 = 1805.8 r/min
T1 = 177.23 N[middot]m
T2 = 175.00 N[middot]m
Crev = 2[middot][pi] rad/r
Ct1 = 60 s/min
Cp = 1000 (N[middot]m[middot]rad/s)/kW
[fnof]record = 5 Hz
Ct2 = 3600 s/hr
[GRAPHIC] [TIFF OMITTED] TR15SE11.047

P1 = 33.41 kW
P2 = 33.09 kW
Using Eq. 1065.650-5,
[Delta]t = 1/5 = 0.2 s
[GRAPHIC] [TIFF OMITTED] TR15SE11.048

    W = 16.875 kW [middot] hr
* * * * *
    (e) * * *
    (4) The following example shows how to calculate mass of emissions
using mean mass rate and mean power:
MCO = 28.0101 g/mol
xCO = 12.00 mmol/mol = 0.01200 mol/mol
n = 1.530 mol/s
fn = 3584.5 r/min = 375.37 rad/s
T = 121.50 N [middot] m
m = 28.0101 [middot] 0.01200 [middot] 1.530
m = 0.514 g/s = 1850.4 g/hr
P = 121.5[middot]375.37
P = 45607 W
P = 45.607 kW
eCO = 1850.4/45.61
eCO = 40.57 g/(kW[middot]hr)

    (f) * * *
    (4) Example. The following example shows how to calculate mass of
emissions using proportional values:

N = 3000
[fnof]record = 5 Hz
efuel = 285 g/(kW[middot]hr)
wfuel = 0.869 g/g
Mc = 12.0107 g/mol
n1 = 3.922 mol/s = 14119.2 mol/hr
xCcombdry1 = 91.634 mmol/mol = 0.091634 mol/mol
xH2Oexh1 = 27.21 mmol/mol = 0.02721 mol/mol
Using Eq. 1065.650-5,
[Delta]t = 0.2 s
[GRAPHIC] [TIFF OMITTED] TR15SE11.049

W = 5.09 (kW[middot]hr)
* * * * *

0
80. Section 1065.655 is amended by revising paragraphs (b), (c)(5),
(d), and (e)(3) and adding paragraph (f) to read as follows:

Sec.  1065.655  Chemical balances of fuel, intake air, and exhaust.

* * * * *
    (b) Procedures that require chemical balances. We require chemical
balances when you determine the following:
    (1) A value proportional to total work, W when you choose to
determine brake-specific emissions as described in Sec.  1065.650(f).
    (2) The amount of water in a raw or diluted exhaust flow,
xH2Oexh, when you do not measure the amount of water to
correct for the amount of water removed by a sampling system. Correct
for removed water according to Sec.  1065.659.
    (3) The calculated dilution air flow when you do not measure
dilution air flow to correct for background emissions as described in
Sec.  1065.667(c) and (d).
    (c) * * *
    (5) The following example is a solution for xdil/exh,x,
xH2Oexh, and xCcombdry using the equations in
paragraph (c)(4) of this section:

[GRAPHIC] [TIFF OMITTED] TR15SE11.050

[GRAPHIC] [TIFF OMITTED] TR15SE11.051

[GRAPHIC] [TIFF OMITTED] TR15SE11.052

[alpha] = 1.8
[beta] = 0.05
[gamma] = 0.0003
[delta] = 0.0001
    (d) Carbon mass fraction. Determine carbon mass fraction of fuel,
wc, using one of the following methods:
    (1) You may calculate wc as described in this paragraph
(d)(1) based on measured fuel properties. To do so, you must determine
values for [alpha] and [beta] in all cases, but you may set [gamma] and
[delta] to zero if the default value listed in Table 1 of this section
is zero. Calculate wc using the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.053

Where:

wc = carbon mass fraction of fuel.
MC = molar mass of carbon.
[alpha] = atomic hydrogen-to-carbon ratio of the mixture of fuel(s)
being combusted, weighted by molar consumption.
MH = molar mass of hydrogen.

[beta] = atomic oxygen-to-carbon ratio of the mixture of fuel(s)
being combusted, weighted by molar consumption.
MO = molar mass of oxygen.
[gamma] = atomic sulfur-to-carbon ratio of the mixture of fuel(s)
being combusted, weighted by molar consumption.
MS = molar mass of sulfur.
[delta] = atomic nitrogen-to-carbon ratio of the mixture of fuel(s)
being combusted, weighted by molar consumption.
MN = molar mass of nitrogen.

    Example:

[alpha] = 1.8
[beta] = 0.05
[gamma] = 0.0003
[delta] = 0.0001
MC = 12.0107
MH = 1.01
MO = 15.9994
MS = 32.065
MN = 14.0067
[GRAPHIC] [TIFF OMITTED] TR15SE11.054

wc = 0.8205

    (2) You may use the default values in the following table to
determine wc for a given fuel:

   Table 1 of Sec.   1065.655--Default Values of [alpha], [beta], [gamma], [delta], and wc, for Various Fuels
----------------------------------------------------------------------------------------------------------------
                                                                                Carbon mass
                      Fuel                        Atomic hydrogen, oxygen, sulfur, and nitrogen-to-   fraction,
                                                   carbon ratios  CH[alpha]O[beta]S[gamma]N[delta]      wc g/g
----------------------------------------------------------------------------------------------------------------
Gasoline.......................................  CH1.85O0S0N0                                              0.866
E10 Gasoline...................................  CH1.92O0.03S0N0                                           0.833
E15 Gasoline...................................  CH1.95O0.05S0N0                                           0.817
E85 Gasoline...................................  CH2.73O0.38S0N0                                           0.576
1 Diesel..............................  CH1.93O0S0N0                                              0.861
2 Diesel..............................  CH1.80O0S0N0                                              0.869
Liquefied Petroleum Gas........................  CH2.64O0S0N0                                              0.819
Natural gas....................................  CH3.78 O0.016S0N0                                         0.747
E100 Ethanol...................................  CH3O0.5S0N0                                               0.521
M100 Methanol..................................  CH4O1S0N0                                                 0.375
----------------------------------------------------------------------------------------------------------------
Residual fuel blends...........................   Must be determined by measured fuel properties as described in
                                                                 paragraph (d)(1) of this section.
----------------------------------------------------------------------------------------------------------------

    (e) * * *
    (3) Fuel mass flow rate calculation. Based on mfuel,
calculate nexh as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.055

Where:

nexh = raw exhaust molar flow rate from which you
measured emissions.
mfuel = fuel flow rate including humidity in intake air.

    Example:

mfuel = 7.559 g/s
wc = 0.869 g/g
MC = 12.0107 g/mol
xCcombdry = 99.87 mmol/mol = 0.09987 mol/mol
xH20exhdry = 107.64 mmol/mol = 0.10764 mol/mol
[GRAPHIC] [TIFF OMITTED] TR15SE11.056

nexh = 6.066 mol/s

    (f) Calculated raw exhaust molar flow rate from measured intake air
molar flow rate, dilute exhaust molar flow rate, and dilute chemical
balance. You may calculate the raw exhaust molar flow rate,
nexh, based on the measured intake air molar flow rate,
nint, the measured dilute exhaust molar flow rate,
ndexh, and the values calculated using the chemical balance
in paragraph (c) of this section. Note that the chemical balance must
be based on dilute exhaust gas concentrations. For continuous-flow
calculations, solve for the chemical balance in paragraph (c) of this
section at the same frequency that you update and record
nint and ndexh. This calculated nexh
may be used for the PM dilution ratio verification in Sec.  1065.546;
the calculation of dilution air molar flow rate in the background
correction in Sec.  1065.667; and the calculation of mass of emissions
in Sec.  1065.650(c) for species that are measured in the raw exhaust.
    (1) Crankcase flow rate. If engines are not subject to crankcase
controls under the standard-setting part, calculate raw exhaust flow as
described in paragraph (e)(1) of this section.
    (2) Dilute exhaust and intake air molar flow rate calculation.
Calculate nexh as follows:

[GRAPHIC] [TIFF OMITTED] TR15SE11.057

    Example:

nint = 7.930mol/s
xraw/exhdry = 0.1544 mol/mol
xint/exhdry = 0.1451 mol/mol
xH2Oexh = 32.46 mmol/mol - 0.03246 mol/mol
ndexh = 49.02 mol/s
nexh = (0.1544-0.145( [middot] (1-0.03246) [middot] 49.02 +
7.930 = 0.4411 + 7.930 = 8.371 mol/s

0
81. Section 1065.659 is amended by revising paragraphs (a), (b), and
(c) to read as follows:

Sec.  1065.659  Removed water correction.

    (a) If you remove water upstream of a concentration measurement, x,
or upstream of a flow measurement, n, correct for the removed water.
Perform this correction based on the amount of water at the
concentration measurement, xH2O[emission]meas, and at the
flow meter, xH2Oexh, whose flow is used to determine the
mass emission rate or total mass over a test interval. For continuous
analyzers downstream of a sample dryer for transient and ramped-modal
cycles, you must apply this correction on a continuous basis over the
test interval, even if you use one of the options in Sec.
1065.145(e)(2) that results in a constant value for
xH2O[emission]meas because xH2Oexh varies over
the test interval. For batch analyzers, determine the flow-weighted
average based on the continuous xH2Oexh values determined as
described in paragraph (c) of this section. For batch analyzers, you
may determine the flow-weighted average xH2Oexh based on a
single value of xH2Oexh determined as described in
paragraphs (c)(2) and (3) of this section, using flow-weighted average
or batch concentration inputs.
    (b) Determine the amount of water remaining downstream of a sample
dryer and at the concentration measurement using one of the methods
described in Sec.  1065.145(e)(2). If you use a sample dryer upstream
of an analyzer and if the calculated amount of water remaining
downstream of the sample dryer and at the concentration measurement,
xH2O[emission]meas, is higher than the amount of water at
the flow meter, xH2Oexh, set xH2O[emission]meas
equal to xH2Oexh. If you use a sample dryer upstream of
storage media, you must be able to demonstrate that the sample dryer is
removing water continuously (i.e., xH2Oexh is higher than
xH2O[emission]meas throughout the test interval).
    (c) For a concentration measurement where you did not remove water,
you may set xH2O[emission]meas equal to xH2Oexh.
You may determine the amount of water at the flow meter,
xH2Oexh, using any of the following methods:
    (1) Measure the dewpoint and absolute pressure and calculate the
amount of water as described in Sec.  1065.645.
    (2) If the measurement comes from raw exhaust, you may determine
the amount of water based on intake-air humidity, plus a chemical
balance of fuel, intake air, and exhaust as described in Sec.
1065.655.
    (3) If the measurement comes from diluted exhaust, you may
determine the amount of water based on intake-air humidity, dilution
air humidity, and a chemical balance of fuel, intake air, and exhaust
as described in Sec.  1065.655.
* * * * *

0
82. Section 1065.660 is revised to read as follows:

Sec.  1065.660  THC, NMHC, and CH4 determination.

    (a) THC determination and initial THC/CH4 contamination
corrections. (1) If we require you to determine THC emissions,
calculate xTHC[THC-FID]cor using the initial THC
contamination concentration xTHC[THC-FID]init from Sec.
1065.520 as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.058

    Example:

xTHCuncor = 150.3 [mu]mol/mol
xTHCinit = 1.1 [mu]mol/mol
xTHCcor = 150.3--1.1
xTHCcor = 149.2 [mu]mol/mol

    (2) For the NMHC determination described in paragraph (b) of this
section, correct xTHC[THC-FID] for initial THC contamination
using Equation 1065.660-1. You may correct xTHC[NMC-FID] for
initial contamination of the CH4 sample train using Equation
1065.660-1, substituting in CH4 concentrations for THC.
    (3) For the CH4 determination described in paragraph (c)
of this section, you may correct xTHC[NMC-FID] for initial
THC contamination of the CH4 sample train using Equation
1065.660-1, substituting in CH4 concentrations for THC.
    (b) NMHC determination. Use one of the following to determine NMHC
concentration, xNMHC:
    (1) If you do not measure CH4, you may omit the
calculation of NMHC concentrations and calculate the mass of NMHC as
described in Sec.  1065.650(c)(5).
    (2) For nonmethane cutters, calculate xNMHC using the
nonmethane cutter's penetration fraction (PF) of CH4 and the
response factor penetration fraction (RFPF) of
C2H6 from Sec.  1065.365, the response factor
(RF) of the THC FID to CH4 from Sec.  1065.360, the initial
THC contamination and dry-to-wet corrected THC concentration
xTHC[THC-FID]cor as determined in paragraph (a) of this
section, and the dry-to-wet corrected CH4 concentration
xTHC[NMC-FID]cor optionally corrected for initial THC
contamination as determined in paragraph (a) of this section.
    (i) Use the following equation for penetration fractions determined
using an NMC configuration as outlined in Sec.  1065.365(d):

[GRAPHIC] [TIFF OMITTED] TR15SE11.059

Where:

xNMHC = concentration of NMHC.
xTHC[THC-FID]cor = concentration of THC, initial THC
contamination and dry-to-wet corrected, as measured by the THC FID
during sampling while bypassing the NMC.
xTHC[NMC-FID]cor = concentration of THC, initial THC
contamination (optional) and dry-to-wet corrected, as measured by
the NMC FID during sampling through the NMC.
RFCH4[THC-FID] = response factor of THC FID to
CH4, according to Sec.  1065.360(d).
RFPFC2H6[NMC-FID] = nonmethane cutter combined ethane
response factor and penetration fraction, according to Sec.
1065.365(d).

    Example:

xTHC[THC-FID]cor = 150.3 [micro]mol/mol
xTHC[NMC-FID]cor = 20.5 [micro]mol/mol
RFPFC2H6[NMC-FID] = 0.019
RFCH4[THC-FID] = 1.05
[GRAPHIC] [TIFF OMITTED] TR15SE11.060

xNMHC = 131.4 [mu]mol/mol

    (ii) For penetration fractions determined using an NMC
configuration as outlined in section Sec.  1065.365(e), use the
following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.061

Where:

xNMHC = concentration of NMHC.
xTHC[THC-FID]cor = concentration of THC, initial THC
contamination and dry-to-wet corrected, as measured by the THC FID
during sampling while bypassing the NMC.
PFCH4[NMC-FID] = nonmethane cutter CH4
penetration fraction, according to Sec.  1065.365(e).
xTHC[NMC-FID]cor = concentration of THC, initial THC
contamination (optional) and dry-to-wet corrected, as measured by
the THC FID during sampling through the NMC.
PFC2H6[NMC-FID] = nonmethane cutter ethane penetration
fraction, according to Sec.  1065.365(e).

    Example:

xTHC[THC-FID]cor = 150.3 [mu]mol/mol
PFCH4[NMC-FID] = 0.990
xTHC[NMC-FID]cor = 20.5 [mu]mol/mol
PFC2H6[NMC-FID] = 0.020
[GRAPHIC] [TIFF OMITTED] TR15SE11.062

xNMHC = 132.3 [mu]mol/mol

    (iii) For penetration fractions determined using an NMC
configuration as outlined in section Sec.  1065.365(f), use the
following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.063

Where:

xNMHC = concentration of NMHC.
xTHC[THC-FID]cor = concentration of THC, initial THC
contamination and dry-to-wet corrected, as measured by the THC FID
during sampling while bypassing the NMC.
PFCH4[NMC-FID] = nonmethane cutter CH4
penetration fraction, according to Sec.  1065.365(f).
xTHC[NMC-FID]cor = concentration of THC, initial THC
contamination (optional) and dry-to-wet corrected, as measured by
the THC FID during sampling through the NMC.
RFPFC2H6[NMC-FID] = nonmethane cutter CH4
combined ethane response factor and penetration fraction, according
to Sec.  1065.365(f).
RFCH4[THC-FID] = response factor of THC FID to
CH4, according to Sec.  1065.360(d).

    Example:

xTHC[THC-FID]cor = 150.3 [micro]mol/mol
PFCH4[NMC-FID] = 0.990
xTHC[NMC-FID]cor = 20.5 [micro]mol/mol
RFPFC2H6[NMC-FID] = 0.019
RFCH4[THC-FID] = 0.980
[GRAPHIC] [TIFF OMITTED] TR15SE11.067

xNMHC = 132.5 [mu]mol/mol

    (3) For a GC-FID, calculate xNMHC using the THC
analyzer's response factor (RF) for CH4, from Sec.
1065.360, and the initial THC contamination and dry-to-wet corrected
THC concentration xTHC[THC-FID]cor as determined in
paragraph (a) of this section as follows:

[GRAPHIC] [TIFF OMITTED] TR15SE11.068

Where:

xNMHC = concentration of NMHC.
xTHC[THC-FID]cor = concentration of THC, initial THC
contamination and dry-to-wet corrected, as measured by the THC FID.
xCH4= concentration of CH4, dry-to-wet
corrected, as measured by the GC-FID.
RFCH4[THC-FID] = response factor of THC-FID to
CH4.

    Example:

xTHC[THC-FID[cor = 145.6 [mu]mol/mol
RFCH4[THC-FID] = 0.970
xCH4 = 18.9 [mu]mol/mol
xNMHC = 145.6-0.970 [middot] 18.9
xNMHC = 127.3 [mu]mol/mol

    (c) CH4 determination. Use one of the following methods
to determine CH4 concentration, xCH4:
    (1) For nonmethane cutters, calculate xCH4 using the
nonmethane cutter's penetration fraction (PF) of CH4 and the
response factor penetration fraction (RFPF) of
C2H6 from Sec.  1065.365, the response factor
(RF) of the THC FID to CH4 from Sec.  1065.360, the initial
THC contamination and dry-to-wet corrected THC concentration
xTHC[THC-FID]cor as determined in paragraph (a) of this
section, and the dry-to-wet corrected CH4 concentration
xTHC[NMC-FID]cor optionally corrected for initial THC
contamination as determined in paragraph (a) of this section.
    (i) Use the following equation for penetration fractions determined
using an NMC configuration as outlined in Sec.  1065.365(d):
[GRAPHIC] [TIFF OMITTED] TR15SE11.069

Where:

xCH4 = concentration of CH4.
xTHC[NMC-FID]cor = concentration of THC, initial THC
contamination (optional) and dry-to-wet corrected, as measured by
the NMC FID during sampling through the NMC.
xTHC[THC-FID]cor = concentration of THC, initial THC
contamination and dry-to-wet corrected, as measured by the THC FID
during sampling while bypassing the NMC.
RFPFC2H6[NMC-FID] = the combined ethane response factor
and penetration fraction of the nonmethane cutter, according to
Sec.  1065.365(d).
RFCH4[THC-FID] = response factor of THC FID to
CH4, according to Sec.  1065.360(d).

    Example:

xTHC[NMC-FID]cor = 10.4 [mu]mol/mol
xTHC[THC-FID]cor = 150.3 [mu]mol/mol
RFPFC2H6[NMC-FID] = 0.019
RFCH4[THC-FID] = 1.05
[GRAPHIC] [TIFF OMITTED] TR15SE11.070

xCH4 = 7.69 [mu]mol/mol

    (ii) For penetration fractions determined using an NMC
configuration as outlined in Sec.  1065.365(e), use the following
equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.071

Where:

xCH4 = concentration of CH4.
xTHC[NMC-FID]cor = concentration of THC, initial THC
contamination (optional) and dry-to-wet corrected, as measured by
the NMC FID during sampling through the NMC.
xTHC[THC-FID]cor = concentration of THC, initial THC
contamination and dry-to-wet corrected, as measured by the THC FID
during sampling while bypassing the NMC.
PFC2H6[NMC-FID] = nonmethane cutter ethane penetration
fraction, according to Sec.  1065.365(e).
RFCH4[THC-FID] = response factor of THC FID to
CH4, according to Sec.  1065.360(d).
PFCH4[NMC-FID] = nonmethane cutter CH4
penetration fraction, according to Sec.  1065.365(e).

    Example:

xTHC[NMC-FID]cor = 10.4 [mu]mol/mol
xTHC[THC-FID]cor = 150.3 [mu]mol/mol
PFC2H6[NMC-FID] = 0.020
RFCH4[THC-FID] = 1.05
PFCH4[NMC-FID] = 0.990
[GRAPHIC] [TIFF OMITTED] TR15SE11.072

xCH4 = 7.25 [mu]mol/mol

    (iii) For penetration fractions determined using an NMC
configuration as outlined in Sec.  1065.365(f), use the following
equation:

[GRAPHIC] [TIFF OMITTED] TR15SE11.073

Where:

xCH4 = concentration of CH4.
xTHC[NMC-FID]cor = concentration of THC, initial THC
contamination (optional) and dry-to-wet corrected, as measured by
the NMC FID during sampling through the NMC.
xTHC[THC-FID]cor = concentration of THC, initial THC
contamination and dry-to-wet corrected, as measured by the THC FID
during sampling while bypassing the NMC.
RFPFC2H6[NMC-FID] = the combined ethane response factor
and penetration fraction of the nonmethane cutter, according to
Sec.  1065.365(f).
PFCH4[NMC-FID] = nonmethane cutter CH4
penetration fraction, according to Sec.  1065.365(f).
RFCH4[THC-FID] = response factor of THC FID to
CH4, according to Sec.  1065.360(d).

    Example:

xTHC[NMC-FID]cor = 10.4 [mu]mol/mol
xTHC[THC-FID]cor = 150.3 [mu]mol/mol
RFPFC2H6[NMC-FID] = 0.019
PFCH4[NMC-FID] = 0.990
RFCH4[THC-FID] = 1.05
[GRAPHIC] [TIFF OMITTED] TR15SE11.074

xCH4 = 7.78 [mu]mol/mol

    (2) For a GC-FID, xCH4 is the actual dry-to-wet
corrected CH4 concentration as measured by the analyzer.

0
83. Section 1065.667 is revised to read as follows:

Sec.  1065.667  Dilution air background emission correction.

    (a) To determine the mass of background emissions to subtract from
a diluted exhaust sample, first determine the total flow of dilution
air, ndil, over the test interval. This may be a measured
quantity or a calculated quantity. Multiply the total flow of dilution
air by the mean mole fraction (i.e., concentration) of a background
emission. This may be a time-weighted mean or a flow-weighted mean
(e.g., a proportionally sampled background). Finally, multiply by the
molar mass, M, of the associated gaseous emission constituent. The
product of ndil and the mean molar concentration of a
background emission and its molar mass, M, is the total background
emission mass, m. In the case of PM, where the mean PM concentration is
already in units of mass per mole of sample, MPM, multiply
it by the total amount of dilution air flow, and the result is the
total background mass of PM, mPM. Subtract total background
mass from total mass to correct for background emissions.
    (b) You may determine the total flow of dilution air by a direct
flow measurement.
    (c) You may determine the total flow of dilution air by subtracting
the calculated raw exhaust molar flow as described in Sec.  1065.655(f)
from the measured dilute exhaust flow. This may be done by totaling
continuous calculations or by using batch results.
    (d) You may determine the total flow of dilution air from the
measured dilute exhaust flow and a chemical balance of the fuel, intake
air, and dilute exhaust as described in Sec.  1065.655. For this
option, the molar flow of dilution air is calculated by multiplying the
dilute exhaust flow by the mole fraction of dilution gas to dilute
exhaust, xdil[sol]exh, from the dilute chemical balance.
This may be done by totaling continuous calculations or by using batch
results. For example, to use batch results, the total flow of dilution
air is calculated by multiplying the total flow of diluted exhaust,
ndexh, by the flow-weighted mean mole fraction of dilution
air in diluted exhaust, xdil[sol]exh. Calculate
xdil[sol]exh using flow-weighted mean concentrations of
emissions in the chemical balance, as described in Sec.  1065.655. The
chemical balance in Sec.  1065.655 assumes that your engine operates
stoichiometrically, even if it is a lean-burn engine, such as a
compression-ignition engine. Note that for lean-burn engines this
assumption could result in an error in emission calculations. This
error could occur because the chemical balance in Sec.  1065.655 treats
excess air passing through a lean-burn engine as if it was dilution
air. If an emission concentration expected at the standard is about 100
times its dilution air background concentration, this error is
negligible. However, if an emission concentration expected at the
standard is similar to its background concentration, this error could
be significant. If this error might affect your ability to show that
your engines comply with applicable standards, we recommend that you
either determine the total flow of dilution air using one of the more
accurate methods in paragraph (b) or (c) of this section, or remove
background emissions from dilution air by HEPA filtration, chemical
adsorption, or catalytic scrubbing. You might also consider using a
partial-flow dilution technique such as a bag mini-diluter, which uses
purified air as the dilution air.
    (e) The following is an example of using the flow-weighted mean
fraction of dilution air in diluted exhaust, xdil[sol]exh,
and the total mass of background emissions calculated using the total
flow of diluted exhaust, ndexh, as described in Sec.
1065.650(c):
[GRAPHIC] [TIFF OMITTED] TR15SE11.075

    Example:

MNOx = 46.0055 g/mol
xbkgnd = 0.05 [micro]mol/mol = 0.05[sdot]10-6
mol/mol
ndexh = 23280.5 mol
xdil[sol]exh = 0.843 mol/mol
mbkgndNOxdexh =
46.0055[sdot]0.05[sdot]10-\6\[sdot]23280.5
mbkgndNOxdexh = 0.0536 g
mbkgndNOx = 0.843 [sdot] 0.0536
mbkgndNOx = 0.0452 g

    (f) The following is an example of using the fraction of dilution
air in diluted exhaust, xdil/exh, and the mass rate of
background emissions calculated using the flow rate of diluted exhaust,
ndexh, as described in Sec.  1065.650(c):
[GRAPHIC] [TIFF OMITTED] TR15SE11.076

    Example:

MNOx = 46.0055 g/mol
xbkgnd = 0.05 [micro]mol/mol = 0.05[sdot]10-\6\
mol/mol

ndexh = 23280.5 mol/s
xdil/exh = 0.843 mol/mol
mbkgndNOxdexh =
46.0055[sdot]0.05[sdot]10-\6\[sdot]23280.5
mbkgndNOxdexh = 0.0536 g/hr
mbkgndNOx = 0.843 [sdot] 0.0536
mbkgndNOx = 0.0452 g/hr

0
84. Section 1065.670 is amended by revising the introductory text to
read as follows:

Sec.  1065.670  NOX intake-air humidity and temperature
corrections.

    See the standard-setting part to determine if you may correct
NOX emissions for the effects of intake-air humidity or
temperature. Use the NOX intake-air humidity and temperature
corrections specified in the standard-setting part instead of the
NOX intake-air humidity correction specified in this part
1065. If the standard-setting part does not prohibit correcting
NOX emissions for intake-air humidity according to this part
1065, correct NOX concentrations for intake-air humidity as
described in this section. See Sec.  1065.650(c)(1) for the proper
sequence for applying the NOX intake-air humidity and
temperature corrections. You may use a time-weighted mean combustion
air humidity to calculate this correction if your combustion air
humidity remains within a tolerance of 0.0025 mol/mol of
the mean value over the test interval. For intake-air humidity
correction, use one of the following approaches:
* * * * *

0
85. Section 1065.675 is amended by revising paragraph (d) to read as
follows:

Sec.  1065.675  CLD quench verification calculations.

* * * * *
    (d) Calculate quench as follows:
    [GRAPHIC] [TIFF OMITTED] TR15SE11.077

Where:

quench = amount of CLD quench.
xNOdry = concentration of NO upstream of a bubbler,
according to Sec.  1065.370(e)(4).
xNOwet = measured concentration of NO downstream of a
bubbler, according to Sec.  1065.370(e)(9).
xH2Oexp = maximum expected mole fraction of water during
emission testing, according to paragraph (b) of this section.
xH2Omeas = measured mole fraction of water during the
quench verification, according to Sec.  1065.370(e)(7).
xNOmeas = measured concentration of NO when NO span gas
is blended with CO2 span gas, according to Sec.
1065.370(d)(10).
xNOact = actual concentration of NO when NO span gas is
blended with CO2 span gas, according to Sec.
1065.370(d)(11) and calculated according to Equation 1065.675-2.
xCO2exp = maximum expected concentration of
CO2 during emission testing, according to paragraph (c)
of this section.
xCO2act = actual concentration of CO2 when NO
span gas is blended with CO2 span gas, according to Sec.
1065.370(d)(9).
[GRAPHIC] [TIFF OMITTED] TR15SE11.078

Where:

xNOspan = the NO span gas concentration input to the gas
divider, according to Sec.  1065.370(d)(5).
xCO2span = the CO2 span gas concentration
input to the gas divider, according to Sec.  1065.370(d)(4).

    Example:

xNOdry = 1800.0 [micro]mol/mol
xNOwet = 1739.6 [micro]mol/mol
xH2Oexp = 0.030 mol/mol
xH2Omeas = 0.030 mol/mol
xNOmeas = 1515.2 [micro]mol/mol
xNOspan = 3001.6 [micro]mol/mol
xCO2exp = 3.2%
xCO2span = 6.1%
xCO2act = 2.98%
[GRAPHIC] [TIFF OMITTED] TR15SE11.079

quench = (-0.0036655-0. 014020171)[sdot]100% = -1.7685671%

Subpart H--[Amended]

0
86. Section 1065.750 is amended by revising paragraphs (a)(3)
introductory text and (a)(4) to read as follows:

Sec.  1065.750  Analytical gases.

* * * * *
    (a) * * *
    (3) Use the following gas mixtures, with gases traceable within
1% of the NIST-accepted value or other gas standards we
approve:
* * * * *
    (4) You may use gases for species other than those listed in
paragraph (a)(3) of this section (such as methanol in air, which you
may use to determine response factors), as long as they are traceable
to within 3% of the NIST-accepted value or other similar
standards we approve, and meet the stability requirements of paragraph
(b) of this section.
* * * * *

0
87. Section 1065.790 is amended by revising paragraph (a) to read as
follows:

Sec.  1065.790  Mass standards.

    (a) PM balance calibration weights. Use PM balance calibration
weights that are certified as NIST-traceable within 0.1% uncertainty.
Calibration weights may be certified by any calibration lab that
maintains NIST-traceability. Make sure your highest calibration weight
has no greater than ten times the mass of an unused PM-sample medium.
* * * * *

Subpart J--[Amended]

0
88. Section 1065.915 is amended by revising Table 1 in paragraph (a) to
read as follows:

Sec.  1065.915  PEMS instruments.

    (a) * * *

                                 Table 1 of Sec.   1065.915--Recommended Minimum PEMS Measurement Instrument Performance
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                      Rise time, t10	90,
           Measurement             Measured quantity    and fall time,     Recording update      Accuracy \1\      Repeatability \1\       Noise \1\
                                        symbol              t90	10             frequency
--------------------------------------------------------------------------------------------------------------------------------------------------------
Engine speed transducer.........  fn................  1 s...............  1 Hz means........  5% of pt. or 1% of  2% of pt. or 1% of  0.5% of max.
                                                                                max.                max.
Engine torque estimator, BSFC     T or BSFC.........  1 s...............  1 Hz means........  8% of pt. or 5% of  2% of pt. or 1% of  1% of max.
 (This is a signal from an                                                                     max.                max.
 engine's ECM)
General pressure transducer (not  p.................  5 s...............  1 Hz..............  5% of pt. or 5% of  2% of pt. or 0.5%   1% of max.
 a part of another instrument)                                                                 max.                of max.
Atmospheric pressure meter        patmos............  50 s..............  0.1 Hz............  250 Pa............  200 Pa............  100 Pa.
General temperature sensor (not   T.................  5 s...............  1 Hz..............  1% of pt. K or 5 K  0.5% of pt. K or 2  0.5% of max 0.5 K.
 a part of another instrument)                                                                                K.
General dewpoint sensor.........  Tdew..............  50 s..............  0.1 Hz............  3 K...............  1 K...............  1 K.
Exhaust flow meter..............  n.................  1 s...............  1 Hz means........  5% of pt. or 3% of  2% of pt..........  2% of max.
                                                                                max.
Dilution air, inlet air,          n.................  1 s...............  1 Hz means........  2.5% of pt. or      1.25% of pt. or     1% of max.
 exhaust, and sample flow meters                                                               1.5% of max.        0.75% of max.
Continuous gas analyzer.........  x.................  5 s...............  1 Hz..............  4% of pt. or 4% of  2% of pt. or 2% of  1% of max.
                                                                                meas.               meas.
Gravimetric PM balance..........  mPM...............  N/A...............  N/A...............  See Sec.            0.5 [mu]g.........  N/A.
                                                                                1065.790.
Inertial PM balance.............  mPM...............  N/A...............  N/A...............  4% of pt. or 4% of  2% of pt. or 2% of  1% of max.
                                                                                meas.               meas.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Accuracy, repeatability, and noise are all determined with the same collected data, as described in Sec.   1065.305, and based on absolute values.
  ``pt.'' refers to the overall flow-weighted mean value expected at the standard; ``max.'' refers to the peak value expected at the standard over any
  test interval, not the maximum of the instrument's range; ``meas'' refers to the actual flow-weighted mean measured over any test interval.

* * * * *

0
89. Section 1065.925 is amended by revising paragraphs (h)(1), (h)(2),
and (h)(3) to read as follows:

Sec.  1065.925  PEMS preparation for field testing.

* * * * *
    (h) * * *
    (1) Select the HC analyzer range for measuring the maximum
concentration expected at the HC standard.
    (2) Zero the HC analyzers using a zero gas or ambient air
introduced at the analyzer port. When zeroing a FID, use the FID's
burner air that would be used for in-use measurements (generally either
ambient air or a portable source of burner air).
    (3) Span the HC analyzer using span gas introduced at the analyzer
port.
* * * * *

Subpart K--[Amended]

0
90. Section 1065.1001 is amended by revising the introductory text and
the definitions for ``Idle speed'', ``Percent (%)'', and ``Round'' and
adding definitions for ``Electric power generation application'',
``High-idle speed'', and ``High-speed governor'' in alphabetical order
to read as follows:

Sec.  1065.1001  Definitions.

* * * * *
    Electric power generation application means an application whose
purpose is to generate a precise frequency of electricity, which is
characterized by an engine that controls engine speed very precisely.
This would generally not apply to welders or portable home generators.
* * * * *
    High-idle speed means the engine speed at which an engine governor
function controls engine speed with operator demand at maximum and with
zero load applied. ``Warm high-idle speed'' is the high-idle speed of a
warmed-up engine.
    High-speed governor means any device, system, or element of design
that modulates the engine output torque for the purpose of limiting the
maximum engine speed.
* * * * *
    Idle speed means the engine speed at which an engine governor
function controls engine speed with operator demand at minimum and with
minimum load applied (greater than or equal to zero). For engines
without a governor function that controls idle speed, idle speed means
the manufacturer-declared value for lowest engine speed possible with
minimum load. This definition does not apply for operation designated
as ``high-idle speed.'' ``Warm idle speed'' is the idle speed of a
warmed-up engine.
* * * * *
    Percent (%) means a representation of exactly 0.01. Numbers
expressed as percentages in this part (such as a tolerance of 2%) have infinite precision, so 2% and 2.000000000% have the same
meaning. This means that where we specify some percentage of a total
value, the calculated value has the same number of significant digits
as the total value. For example, 2% of a span value where the span
value is 101.3302 is 2.026604.
* * * * *
    Round means to apply the rounding convention specified in Sec.
1065.20(e), unless otherwise specified.
* * * * *

0
91. Section 1065.1005 is amended by revising the introductory text and
paragraphs (a), (e), (f)(2), and (g) to read as follows:

Sec.  1065.1005  Symbols, abbreviations, acronyms, and units of
measure.

    The procedures in this part generally follow the International
System of Units (SI), as detailed in NIST Special Publication 811,
which we incorporate by reference in Sec.  1065.1010. See Sec.  1065.20
for specific provisions related to these conventions. This section
summarizes the way we use symbols, units of measure, and other
abbreviations.
    (a) Symbols for quantities. This part uses the following symbols
and units of measure for various quantities:

--------------------------------------------------------------------------------------------------------------------------------------------------------
      Symbol              Quantity                Unit                        Unit symbol                        Units in terms of SI base units
--------------------------------------------------------------------------------------------------------------------------------------------------------
[alpha]...........  atomic hydrogen to    mole per mole.......  mol/mol                                 1
                     carbon ratio.
A.................  area................  square meter........  m \2\                                   m \2\
A0................  intercept of least    ....................  ......................................  ................................................
                     squares regression.
A1................  slope of least        ....................  ......................................  ................................................
                     squares regression.
[beta]............  ratio of diameters..  meter per meter.....  m/m                                     1
[beta]............  atomic oxygen to      mole per mole.......  mol/mol                                 1
                     carbon ratio.
C#................  number of carbon      ....................  ......................................  ................................................
                     atoms in a molecule.
d.................  Diameter............  meter...............  m                                       m
DR................  dilution ratio......  mole per mol........  mol/mol                                 1
[egr].............  error between a       ....................  ......................................  ................................................
                     quantity and its
                     reference.
e.................  brake-specific        gram per kilowatt     g/(kW[middot]hr)                        g[middot]3.6-1[middot]10\6\[middot]m-
                     emission or fuel      hour.                                                         2[middot]kg[middot]s\2\
                     consumption.
F.................  F-test statistic....  ....................  ......................................  ................................................
f.................  frequency...........  hertz...............  Hz                                      s-1
fn................  angular speed         revolutions per       r/min                                   2[middot][pi][middot]60-1[middot] m[middot]m-
                     (shaft).              minute.                                                       1x[middot]s-1
[gamma]...........  ratio of specific     (joule per kilogram   (J/(kg[middot]K))/(J/(kg[middot]K))     1
                     heats.                kelvin) per (joule
                                           per kilogram
                                           kelvin).
K.................  correction factor...  ....................  ......................................  1
l.................  length..............  meter...............  m                                       m
[mu]..............  viscosity, dynamic..  pascal second.......  Pa[middot]s                             m-1[middot]kg[middot]s
M.................  molar mass\1\.......  gram per mole.......  g/mol                                   10-3[middot]kg[middot]mol-1
m.................  mass................  kilogram............  kg                                      kg
m.................  mass rate...........  kilogram per second.  kg/s                                    kg[middot]s-1
[nu]..............  viscosity, kinematic  meter squared per     m-2/s                                   m-2[middot]s-1
                                           second.
N.................  total number in       ....................  ......................................  ................................................
                     series.
n.................  amount of substance.  mole................  mol                                     mol
[eta].............  amount of substance   mole per second.....  mol/s                                   mol[middot]s-1
                     rate.
P.................  power...............  kilowatt............  kW                                      10\3\[middot]m\2\[middot]kg[middot]s-3
PF................  penetration fraction  ....................  ......................................  ................................................
p.................  pressure............  pascal..............  Pa                                      m-1[middot]kg[middot]s-2
[rho].............  mass density........  kilogram per cubic    kg/m\3\                                 kg[middot]m-3
                                           meter.
r.................  ratio of pressures..  pascal per pascal...  Pa/Pa                                   1
R2................  coefficient of        ....................  ......................................  ................................................
                     determination.
Ra................  average surface       micrometer..........  [mu]m                                   10--6 m
                     roughness.
Re#...............  Reynolds number.....  ....................  ......................................  ................................................
RF................  response factor.....  ....................  ......................................  ................................................
RH................  relative humidity...  ....................  ......................................  ................................................
[sigma]...........  non-biased standard   ....................  ......................................  ................................................
                     deviation.
S.................  Sutherland constant.  kelvin..............  K                                       K
SEE...............  standard estimate of  ....................  ......................................  ................................................
                     error.
T.................  absolute temperature  kelvin..............  K                                       K
T.................  Celsius temperature.  degree Celsius......  [deg]C                                  K-273.15
T.................  torque (moment of     newton meter........  N[middot]m                              m-2[middot]kg[middot]s-2
                     force).
t.................  time................  second..............  s                                       s
[Delta]t..........  time interval,        second..............  s                                       s
                     period, 1/frequency.

V.................  volume..............  cubic meter.........  m\3\                                    m\3\
V.................  volume rate.........  cubic meter per       m\3\/s                                  m\3\[middot]s-1
                                           second.
W.................  work................  kilowatt hour.......  kW[middot]hr                            3.6[middot]10-6[middot]m\2\[middot]kg[middot]s-2
wc................  carbon mass fraction  gram per gram.......  g/g                                     1
x.................  amount of substance   mole per mole.......  mol/mol                                 1
                     mole fraction \2\.
x8................  flow-weighted mean    mole per mole.......  mol/mol                                 1
                     concentration.
y.................  generic variable....  ....................  ......................................  ................................................
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ See paragraph (f)(2) of this section for the values to use for molar masses. Note that in the cases of NOX and HC, the regulations specify effective
  molar masses based on assumed speciation rather than actual speciation.
\2\ Note that mole fractions for THC, THCE, NMHC, NMHCE, and NOTHC are expressed on a C1 equivalent basis.

* * * * *
    (e) Subscripts. This part uses the following subscripts to define a
quantity:

------------------------------------------------------------------------
                 Subscript                            Quantity
------------------------------------------------------------------------
abs.......................................  absolute quantity.
act.......................................  actual condition.
air.......................................  air, dry.
atmos.....................................  atmospheric.
cal.......................................  calibration quantity.
CFV.......................................  critical flow venturi.
cor.......................................  corrected quantity.
dil.......................................  dilution air.
dexh......................................  diluted exhaust.
exh.......................................  raw exhaust.
exp.......................................  expected quantity.
hi,idle...................................  condition at high-idle.
i.........................................  an individual of a series.
idle......................................  condition at idle.
in........................................  quantity in.
init......................................  initial quantity, typically
                                             before an emission test.
j.........................................  an individual of a series.
max.......................................  the maximum (i.e., peak)
                                             value expected at the
                                             standard over a test
                                             interval; not the maximum
                                             of an instrument range.
meas......................................  measured quantity.
out.......................................  quantity out.
part......................................  partial quantity.
PDP.......................................  positive-displacement pump.