when it comes to evaporative emissions certification. With this notice
we are proposing a revised approach to the CARB/EPA reciprocity with
regard to evaporative and refueling emissions. A uniform national
certification test fuel is important to the design of fuel/evaporative
systems which will operate effectively across the U.S. Consistent with
our desire to have a national program with vehicles designed for E15 as
discussed in Section IV.D, and

consistent with our treatment of exhaust emission standards, we are
proposing a 9 RVP test fuel with 15 percent ethanol for all evaporative
(hot soak plus diurnal, canister bleed, and leak emission standards)
and refueling emissions testing. Thus, after the evaporative emissions
fuel phase-in discussed above (ending after the 2019 MY), EPA will no
longer accept test data on CARB test fuel and diurnal test
temperatures. However, CARB has agreed to accept emission test data on
EPA test fuel and temperature conditions for certification such that a
uniform national program could still exist. This approach applies to
all evaporative and refueling emission standards.
    Generally, any vehicle family counted in the Tier 3 evaporative
emission standards phase-in must be certified on Tier 3 certification
test fuel using EPA test procedures. However, EPA recognizes that the
California and federal evaporative emission standard programs would be
starting from different bases and that the transition provisions are
different in some ways. For example, the proposed EPA program starts in
the 2017 MY but after that has the same basic program construct as CARB
in 2018. However, prior to the 2017 MY, CARB has a ZEV program
provision which will continue to bring zero evap technology into the
fleet before 2017. To capitalize on this technology and to facilitate
transition, we are proposing that any CARB evaporative emission test
data from MYs 2015 and 2016 certifications could be used in federal
certification for those evaporative/refueling families through the 2019
MY. Assuming these vehicle families meet Tier 3 evaporative emission
standards and they are sold nationwide they could be included in the
percentage phase-in calculations as Tier 3 vehicles. A good example of
these would be vehicles meeting CARB Option 1 standards discussed
above. If the vehicles do not meet the Tier 3 evaporative emission
requirements manufacturers could potentially sell them nationwide, but
they would not be included as compliant vehicles in the percentage
phase-in calculation. EPA proposes a similar provision for a
manufacturer which elects to use the CARB test procedures and test
fuels to meet the refueling emission standard. That is, if a
manufacturer uses evaporative emission test data from 2015 or 2016
model year CARB certifications to meet the Federal requirements in
2017-2019 model years, it may also use CARB refueling emission test
data from model year 2015 and 2016 certifications for federal
certification for the refueling requirements for those evaporative/
refueling families through the 2019 MY. Any in-use testing on vehicle
families certified on this data would be conducted using the CARB
temperature conditions and test fuel and the CARB ethanol SHED
adjustment value of 1.08 for 10 percent ethanol. However, by the 2020
MY all vehicles would have to be certified using EPA certification test
fuel and test procedures. In the interim, the equivalency and
acceptance by EPA of certification on California test fuels is
dependent on our proposed 9 psi RVP level for the certification test
fuel. Were we to require the more stringent level of 10 psi RVP more
typical of E10 as discussed in section IV.D.1, testing using California
test fuels and conditions would no longer be equivalent.
e. Evaporative and Refueling Emission Standards for Various Fuels
    The evaporative and refueling emission standards today apply in
different ways to different fuels. In the case of gasoline, all the
standards apply and testing is required for certifying all vehicles.
Evaporative emission standards do not apply for diesel-fueled vehicles;
the refueling standards apply to diesel-fueled vehicles, but
manufacturers can get EPA approval to omit testing for certification.
For other fuels, there is a mix of standards applying or not applying,
and if standards apply, testing is either required or not required. The
statutory provisions in this regard are straightforward: Clean Air Act
section 202(k) specifies that gasoline-fueled vehicles must be
certified to evaporative emission standards, and section 202(a)(6)
specifies that all motor vehicles be certified to refueling emission
standards. This raises two questions. First, we request comment on
using this rulemaking as the proper context for applying the refueling
standards to vehicles powered by every kind of fuel. Where standards do
not apply today (natural gas, fuel cells, electric, etc.), we would
expect to waive test requirements for certification, so this would not
be any substantial burden. Dedicated ethanol-fueled vehicles would face
a new requirement, but we are not aware that there are any such
vehicles today.
    Second, we have the discretion to apply evaporative emission
standards to vehicles powered by fuels other than gasoline. The
standards expressly do not apply for diesel fuel. By omission, the
standards do not apply for dedicated ethanol-fueled vehicles, fuel-cell
vehicles, and electric vehicles. The standards apply for natural gas
and liquefied petroleum gas even though these are sealed systems with
no emission control systems for controlling evaporative emissions. We
request comment on adjusting the regulations such that evaporative
emission standards apply only to volatile liquid fuels, which is the
approach we have taken for nonroad applications (see, for example, 40
CFR 1060.801). Under this approach, diesel fuel would continue to be
excluded from standards because it is nonvolatile. This approach would
also exclude natural gas and liquefied petroleum gas because they are
not liquid fuels at atmospheric pressure.
5. Improvements to In-Use Performance of Fuel Vapor Control Systems
a. Background on Data Related to In-Use Performance
    As part of the Compliance Assistance Program (CAP 2000) in-use
verification program (IUVP) \295\ the manufacturers began testing the
evaporative emissions performance of small samples of in-use vehicles
owned and used by the public. These regulations can be found at 40 CFR
86 1845-01, and 1845-04. In 2000, EPA extended this requirement to
cover chassis-certified HDVs, which for these purposes are basically
all HDGVs up to 14,000 lbs GVWR.\296\ The in-use testing for
evaporative emissions started in 2004 for 2001 MY LDVs, LDTs, and MDPVs
and in 2008 for 2007 MY chassis certified HDGVs. Current IUVP data for
evaporative emissions covers about 1800 vehicle tests. This data shows
that when evaluated in the laboratory using certification test
procedures, the vast majority (over 95 percent) of the vehicles pass
the evaporative emission standards to which they were certified. While
this information is indicative of good in-use performance, it has
limitations. First, the test results are for small sample sizes. For
the approximately 150 million LDVs, LDTs, MDPVs, and chassis-certified
HDGVs produced between 2001 (the start of the IUVP program) and 2010
(latest available data), only about 0.001 percent of vehicles were
tested. Second, the IUVP regulations place limits on the age/mileage
for vehicle testing. Each model year is tested in two ``batches,''
nominally at the one and four year age points. One year old vehicles
must have at least 10,000 miles and four year old vehicles must have at
least 50,000 miles with at least one within the higher mileage group
having

an odometer reading of at least 75 percent of useful life (90,000 miles
for most Tier 2 vehicles). The useful life period for LDVs and LDT1s/
LDT2s is 10 years/120,000 miles, for LDT3s/LDT4s/MDPVs and complete
HDGVs it is 11 years/120,000 miles. Thus, few firm conclusions can be
drawn about full useful life emissions performance.
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    \295\ 64 FR 23906 (May 4, 1999).
    \296\ 65 FR 59922-59924 (October 6, 2000).
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    Recent evaporative emission testing conducted by EPA and others
evaluated in-use LDVs and LDTs certified to meet the enhanced
evaporative emission standards implemented for 1996 and later model
years \297\ as well as Tier 2 standards implemented for 2004 and later
model year vehicles. Three Coordinating Research Council (CRC) programs
(E-77-2/2b/2c), tested evaporative emission levels of vehicles with
varying amounts of ethanol and levels of RVP in the gasoline test
fuel.\298\ These programs were unique in that a subset of the vehicle
SHED tests were of vehicles with implanted leaks at the nominal minimal
level of detection for OBD systems (0.020 inch) in three different
locations in the fuel/evaporative control system. These tests showed
hydrocarbon emission rates 2-10 times greater than for the same
vehicles tested in the SHED without the leaks and showed an order of
magnitude of difference depending on where the leak was introduced.
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    \297\ 58 FR 16002 (March 24, 1993).
    \298\ CRC E-77 reports: Haskew, H., Liberty, T. (2008). Vehicle
Evaporative Emission Mechanisms: A Pilot Study, CRC Project E-77;
Haskew, H., Liberty, T. (2010). Enhanced Evaporative Emission
Vehicles (CRC E-77-2); Haskew, H., Liberty, T. (2010). Evaporative
Emissions from In-Use Vehicles: Test Fleet Expansion (CRC E-77-2b);
Haskew, H., Liberty, T. (2010). Study to Determine Evaporative
Emission Breakdown, Including Permeation Effects and Diurnal
Emissions Using E20 Fuels on Aging Enhanced Evaporative Emissions
Certified Vehicles, CRC E-77-2c.
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    Furthermore, the CRC E-77-2 evaporative emissions test programs
which looked at permeation in aged vehicles meeting EPA's enhanced
evaporative emission control standards, introduced a new Static Test
Procedure which pressurized the vapor space and activated the fuel pump
during different portions of the SHED test, while the vent from the
vehicle canister was routed to a trap canister outside of the SHED. By
pressurizing the vapor space it was possible to determine if there was
a vapor leak in the system by looking for a slope change in the vapor
concentration in the SHED over time relative to permeation alone.
Similarly, by activating the fuel pump it was possible to determine if
there was a liquid leak in the system by looking for a slope change in
the vapor concentration in the SHED over time relative to permeation
alone. Out of the 15 randomly recruited vehicles in the program, seven
of them displayed vapor and/or liquid leaks on one or more fuel
ethanol/RVP combination (4 of these 7 were Tier 2 vehicles). A closer
look at the data indicates that over the course of the study, which
covered a two to four year period depending on the vehicle, the
magnitude of the leaks increased with time.
    These studies taken together were of concern to EPA with regard to
the in-use performance of evaporative emission control systems because
they indicated that leaks could be a large portion of the evaporative
emissions inventory if they occurred in even a relatively small
fraction of the in-use fleet. The key missing piece of information was
how often the leaks of 0.020 inches or larger occur in the fleet.
    To help us better understand this concern, EPA partnered with the
Colorado Department of Public Health and Environment (CDPHE) and with
CRC as an advisor for a pilot field study in Denver in the summer of
2008 to assess the frequency of high evaporative emissions vehicles in
the fleet. The project identified high evaporative emission emitters
through an innovative screening tool known as a remote sensing device
(RSD). The vehicles were identified at the entrance to the Inspection
and Maintenance (I/M) station as high evaporative emission emitters.
The operators of these vehicles were asked to participate in further
evaluation using a Portable Sealed Housing for Evaporative
Determination (PSHED) in addition to a modified California method test
procedure to locate the source of the high emissions indicated by the
PSHED level.\299\ The CDPHE continued to collect the same type of data
in different locations in the Denver area for the next two summers.
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    \299\ DeFries, T., Lindner, J., Kishan, S., Palacios, C. (2011).
Investigation of Techniques for High Evaporative Emissions Vehicle
Detection: Denver Summer 2008 Pilot Study at Lipan Street Station.
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    Of the 5,830 vehicles which came through the Ken Caryl I/M station
in 2009, 601 were identified as potentially high evaporative emitters
using the RSD tool.\300\ Of these, 84 vehicle owners agreed to be
included in the PSHED evaluation that summer. Furthermore, 110
additional vehicles were recruited which were potentially low to
marginally high evaporative emitters.\301\ The study was structured to
recruit higher evaporative emitting vehicles more heavily than lower
emitting vehicles. Afterwards the percentages were adjusted to
represent the actual mix in the fleet of light duty vehicles. Thus, it
was determined that 10 percent of the fleet had evaporative emissions
which exceeded a cut point reflecting an in-use evaporative emission
rate of about 1 gram of total HC over 15 minutes (see Table 5-9 in the
2012 DeFries report referenced above). This value is approximately the
emission rate that would be expected from a leak of 0.020 inches which
is the detection standard for OBD II systems.\302\
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    \300\ DeFries, T; Palacios, C., Kishan, S. (2012), Estimated
Summer Hot Soak Distributions for the Denver's Ken Caryl I/M Station
Fleet.
    \301\ A selection bin structure was used based on indicated
evaporative emissions levels recruitment heavier at the higher
emission end. Thus, there was a gradation even in the lower level
bins where many of the vehicles would be considered marginal and not
passing the evaporative emission standard even if they were not
considered higher than the 1 g/15 minutes which our study found to
be the lower range detectable by the RSD from the 2010 Ken Caryl
report cited above.
    \302\ Compare the first 15 minutes of hot soak data from the
field studies with implanted leaks in E-77-2 studies.
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    An examination of the test data reveals two additional significant
points. First, the data indicates a trend for greater frequency of
leaks in older vehicles. This is not unexpected given the manner in
which factors such as vibration, fuel quality, weather elements,
corrosion, maintenance, and other operating conditions affect the
durability of system components, fittings, and connections over time.
Second, there were relatively few newer model year vehicles in the
population surveyed. This is expected and almost unavoidable since the
Colorado I/M program generally exempts vehicles which are four years
old or newer. While it is reasonable to expect there to be a lower
prevalence of leaks in newer vehicles, the lack of data for newer
vehicles does not necessarily indicate that no problems exist in newer
model year vehicles or that problems will not occur in the future with
Tier 3 vehicles.
    Since many of the vehicles in the sample group met OBD requirements
for evaporative system leak monitoring, it was deemed useful to examine
whether the OBD system identified the leak. As mentioned above,
approximately 10 percent of the vehicles in the ``adjusted fleet'' had
vapor leaks which were of the magnitude expected from a 0.020 inch or
larger leak. Over the three years of study, there were a total of 180
SHED tests (either PSHED or laboratory SHED) on vehicles with OBD data
collected in the I/M program. Of these 180 vehicles, 171 had the
evaporative OBD monitors ready. Of these, 171 vehicles, 20 were found
to have emission rates of 1 g/15 min in the PSHED (the emission rate
linked to a 0.020'' leak). Of these 20 vehicles only 3 came into the I/
M test

with an OBD diagnostic trouble code (DTC) set indicating an evaporative
system problem.303 304 A closer look, including field
inspection comments, of the 20 vehicles shows that half were not
expected to diagnose the problem because it was outside of the OBD
system design capabilities. Of the vehicles which potentially should
have set an evaporative DTC, at least 50 percent and perhaps as much as
70 percent of codes were not set on high evap emissions vehicles. The
lack of codes being set for these vehicles may reflect OBD performance
issues or allowances (known as enable criteria) in the OBD regulations
regarding when the OBD evaporative emission leak monitoring system is
not required to operate or situations when the monitor is otherwise not
ready for what may be allowable reasons such as an allowable
deficiency.
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    \303\ In the E-77-2 programs the 0.02 inch leaks implanted near
the top of the tank and at the canister connection had hot soak
measurements which averaged approximately 1 g/15 minutes PSHED
measurement. This also happens to be the lower end of the detectable
range of evaporative emissions by the RSD. Since the OBD monitor is
expected to detect a .020'' leak wherever it is located, the DTC
should be set.
    \304\ Palacios, C., Weatherby, M., DeFries, T., Lindner, J.,
Kishan, S. (2012). Evaluation of the Effectiveness of On-Board
Diagnostic (OBD) Systems in Identifying Fuel Vapor Losses from
Light-Duty Vehicles.
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    To better understand this issue EPA has examined evaporative
emission system DTC and monitor ready information from I/M programs
from Texas and California.\305\ Since the data was gathered by the
states under different protocols and time periods, the content of the
data sets are not identical. To provide some degree of uniformity in
our analysis, we examined the data for five MY (2000-2004) but within
each state we only looked at calendar years of data beginning after the
initial state I/M exemption period (2-4 calendar years depending on the
state) had passed. Thus the analysis focused on I/M OBD information for
calendar years 2004-2010. Examined together, the data generally
indicates the following:
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    \305\ Fulper, C. (2013, February). Preliminary Analysis of OBD
Evaporative System Information from I/M Stations--California and
Texas, Memorandum to the docket.
---------------------------------------------------------------------------

     Depending on age, 0.3-2.5 percent of vehicles with
evaporative monitors ready came into the I/M stations with evaporative
related MIL or DTCs set.
     The percent of vehicles with evaporative emission related
MILs set increased by a factor of 2-4 over about 5 years.
     Evaporative emission monitors were not ready for 3-16
percent of vehicles when arriving at the I/M station.
     The percent of vehicles with monitors ready at the I/M
station generally decreased by 3 to 7 percentage points over about 5-6
years; decrease was less for model year vehicles less than five years
old.
     While it varies by age, 60-80 percent of evaporative
system DTCs are leak related.
    There is no question of the value of OBD leak monitoring for
evaporative systems, especially when owners complete needed repairs.
Undoubtedly these percentages and thus in-use leak values would be
higher without OBD evaporative system leak monitoring. However, this
data suggests that EPA OBD regulations in place for 2000-2004 MY
vehicles would not alone be sufficient to address concerns regarding
the emission effects of vapor leaks from the fuel and evaporative
control systems.\306\
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    \306\ For further information see CARB reports ``Technical
Status and Proposed Revisions to Malfunction and Diagnostic System
Requirements for 1994 and Subsequent Model-Year Passenger Cars,
Light-Duty Trucks, and Medium-Duty Vehicles and Engines (OBD II)''
October, 1994 and ``Technical Status and Revisions to Malfunction
and Diagnostic System Requirements for 2004 and Subsequent Model
Year Passenger Cars, Light-Duty Trucks, and Medium-Duty Vehicles and
Engines (OBD II) March 2002.
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    In summary, information gathered from evaporative emissions testing
conducted in the IUVP program indicates that relatively low mileage/
newer vehicles perform well when evaluated under laboratory conditions.
However, data gathered from in-use testing conducted by EPA, Colorado,
and others indicates that as vehicles age some vehicles have a
propensity to develop leaks in the fuel/evaporative system and that
these leaks increase in size as the vehicles age. Beyond this, a review
of OBD evaporative system leak monitor data from the I/M programs of
two states revealed four important trends: (1) even when the OBD system
identifies leaks owners do not always respond by getting the needed
repair completed, (2) the fraction of vehicles with leaks identified by
OBD increases as vehicles age, (3) vehicles sometimes are operating in
conditions in which the OBD leak monitor is not ready to identify a
potential problem, and (4) evaporative system leaks are the dominant
DTC for vehicles with monitors ready and evaporative system DTC set.
    The propensity for leaks in the vehicle fleet has the potential to
reduce the benefits of the Tier 3 evaporative emission standards
substantially. If on any given day, as few as five percent of Tier 3
vehicles had a leak(s) of 0.020 inches or greater this would cause in-
use emissions equivalent to all of the projected emission reductions
from the proposed Tier 3 evaporative emission standards on that
day.\307\ Thus, EPA is proposing three measures to address this issue:
(1) An emission standard focused on reducing fuel/evaporative system
vapor leaks over the vehicle useful life, (2) an upgrade to OBD
emissions monitoring requirements to improve their role in identifying
problems and improving in-use emissions performance, and (3) additions
to the IUVP program focused on testing a broader sample of fuel/
evaporative system leaks in IUVP than is done for evaporative emission
standards alone.
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    \307\ This is based on five percent of vehicles and 4-5 trips
(hot soaks) per day at 1 g/hot soak. Five percent is a reasonable
value for this illustration since as mentioned above 0.3-2.5 percent
of vehicles come in to I/M stations with evaporative system MILs or
DTCs and 60-80 percent of these were leak-related DTCs. Thus, it is
reasonable to project that the fleet average is higher since vehicle
repair just before I/M is common, evaporative emission monitors were
not ready on 3-16 percent of vehicles, and 18 states do not have any
form of I/M at all and repair rates in response to a MIL may be
lower.
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b. Proposed Leak Emission Standard
    The evaporative emission standards in this proposal will help to
promote widespread use of improved technology and materials which will
reduce evaporative emissions in-use. The proposed new requirement for a
leak emission standard and procedure will help to ensure the durability
of Tier 3 evaporative emission control systems nationwide.
    Based on the information described above concerning evaporative
emissions in-use, we believe a leak emission standard is necessary to
meet our goal that vehicles meeting Tier 3 evaporative emission
requirements not have fuel/evaporative system vapor leaks. Toward that
end, we are proposing a leak emission standard that would have to be
met both at new vehicle certification and in use. The leak emission
standard would apply beginning in the 2018 MY to any vehicle certified
to the Tier 3 evaporative emission standards or a CARB carryover
vehicle counted toward the sales percentage phase-in requirements,
including LDVs, LDTs, MDPVs, and complete HDGVs up to 14,000 lbs GVWR.
The emission standard would be applicable for the same useful life
period as for the evaporative emission standards that apply to the
vehicle. The standard would apply to vehicles using volatile fuel
(e.g., gasoline, FFV, and methanol

fuel vehicles, but not diesel or CNG vehicles).
    To be compatible with CARB OBD requirements being met by most
manufacturers and the OBD requirements included in this notice, we are
proposing that the leak emission standard be expressed in the form of a
cumulative equivalent orifice diameter. We are proposing a value of
0.02 inches.\308\ The standard basically requires that the cumulative
equivalent diameter of any orifices or ``leaks'' in the system not
exceed 0.02 inches. This is consistent with California OBD requirements
(and those being proposed in this rule as well) that the OBD system be
capable of identifying leaks in the fuel/evaporative system of a
cumulative equivalent diameter of 0.020 inches EPA believes an emission
standard at this level is feasible since earlier testing programs
identified vehicles with essentially no leaks and it is essentially
equivalent to that required for CARB OBD evaporative system leak
monitoring. As discussed in the technological feasibility section
above, the actions manufacturers will have to take to meet the proposed
Tier 3 evaporative emission standards are expected to do more to
address potential leak points and thus in a broader sense to improve
in-use durability for evaporative control systems compared to vehicles
meeting earlier or current evaporative emission standards.
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    \308\ Current OBD regulations specify that if the fuel tank
volume exceeds 25 gallons then the manufacturer may seek a larger
leak detection orifice value. If a manufacturer seeks and is granted
a larger value for OBD leak detection purposes, then that same
numerical value becomes the leak emission standard value. We would
not expect this value to exceed 0.040 inches.
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    The proposed leak emission standard would provide added assurance
that as the manufacturers design for ``zero evap'' standards they also
design the systems to avoid leaks over the full useful life. We are
proposing a leak emission standard of 0.02 inches which with rounding
is a bit less stringent than the 0.020 inch OBD fuel/evaporative system
leak monitoring requirement. EPA believes this level of precision is
sufficient to accomplish the air quality objective and yet provides
some compliance margin between the emission standard and the monitor
requirement which is reflected through multipliers for the exhaust
emission standards monitored through OBD. EPA asks for comment and
rationale on setting the standard at 0.02 inches equivalent diameter or
the more stringent 0.020 inch equivalent diameter specified for OBD
evaporative system leak monitoring. If finalized as proposed, the
emission standard would be specified to one significant digit (e.g.,
0.02 inches) but would have to be measured and reported to at least two
significant digits.
    The proposed leak emission standard would apply at the time of
certification as well as during confirmatory and in-use verification
program testing. We do not expect that new vehicles being certified
would have a leak problem, and since a vehicle with a leak would likely
fail the evaporative emissions SHED test, there is little value in
mandating a leak test at certification. Thus, EPA proposes to allow
manufacturers to attest to compliance with the leak emission standard
at certification.
    To implement the proposed leak emission standard within the current
regulatory structure a few minor changes are needed. First, current EPA
regulations such as those at Sec.  86.098-24, specify criteria for
evaporative/refueling emission families. EPA believes this basic
structure is appropriate for the leak emission standard, with the
additional criteria that vehicles in the same evaporative/refueling
family must use the same basic approach to OBD leak detection.
Significantly different volume fuel tanks would likely also be a family
determinant, but we believe this is already covered by the evaporative/
refueling family criteria. Second, since the leak emission standard is
a pass/fail requirement and not an emission rate, there is no
requirement for the application of a deterioration factor. Third, EPA
proposes to require that the manufacturers recommend one or more leak
entry test points for each family. This point should be outside of the
gas cap/fillpipe area, since our experience indicates that testing
could always be done through that point of entry to the fuel/
evaporative system.
    EPA asks for comment on the timing, form and level of the proposed
emission standard. EPA believes that linking the timing of the proposed
leak emission standard to the implementation of proposed Tier 3
evaporative emission standards in 2018 provides adequate lead time and
is consistent with the technical rationale supporting the feasibility
of the Tier 3 evaporative emission standard.
c. Proposed Leak Emission Standard Test Procedure
    In order to implement a new leak emission standard, a leak test
procedure is required. The fundamental concepts underlying fuel/
evaporative system leak test are not new to the manufacturers. There is
already a simple leak check in 40 CFR 86.608-98(a)(xii)(A) and in the
past at least three states included a fuel/evaporative system pressure
leak test in I/M programs. More importantly, all LDVs, LDTs, MDPVs and
HDGVs manufactured today have the onboard capability to run a pressure
or vacuum leak based check on the vehicle's evaporative emission system
as part of OBD evaporative system leak monitoring. These systems employ
either positive or negative pressure leak detection pumps or operate
based on natural vacuum for negative pressure leak detection. EPA is
proposing a test based on a similar concept of placing the system under
a slight positive pressure (but from an external source), measuring the
flow needed to maintain that pressure in the fuel/evaporative control
system, and converting that flow rate to an equivalent orifice
diameter. With regards to the test procedure we will first discuss
where the leak test could occur in the FTP test sequence. We will then
discuss how the test is proposed to be conducted.
    First with regard to when the test would be conducted within the
current FTP sequence we are proposing that it be inserted immediately
following the first two preconditioning steps within the FTP sequence
(see Figure B96-10 in 40 CFR 86.130-96). Thus, the vehicle
preconditioning steps for the leak test would be: (1) fill the vehicle
fuel tank to 40 percent of capacity using the appropriate certification
test fuel and then (2) let the vehicle soak for a minimum of a six hour
period at a temperature in the range of 68-86[emsp14][deg]F. EPA
proposes that the test be conducted with 9 RVP E15 test fuel for both
certification and IUVP. This is the same preconditioning that is called
for today in 40 CFR part 86 subpart B for exhaust, evaporative, and
refueling emissions testing. After preconditioning is complete, the
leak test would be conducted and the test sequence could then proceed
as prescribed in subpart B or testing terminated if the purpose was
only to conduct leak testing. EPA believes this modest level of
preconditioning is sufficient to create standard conditions which
enable repeatable and reliable measurement results. Preconditioning
could not include any prescreening for leaks nor would any tightening
of fittings or connections be permitted.
    After preconditioning is complete, manufacturers would then run the
leak test. Each complete test would involve running the test procedure
at one entry point in the system. Presumably this would be either near
the back of the fuel system (perhaps near the gas cap) or near the
front of the fuel system on the

pressure side of the locations near where the system is sealed (perhaps
at the canister vent). If the fuel/evaporative system has an imbedded
evaporative system test port then that point could be used.
Alternatively, manufacturers could also develop a test rig such as a
``fill pipe extension'' which would screw into the fill pipe opening
using cap threads at one end and on the other end have threads to screw
the fill pipe vehicle cap in place. Within this extension there would
be an access port for the leak test equipment to be attached. Thus, the
full system could be tested without any direct intrusion or the need
for a separate gas cap assessment. The manufacturer would have to
specify the test point at the time of the pre-certification meeting. If
the manufacturer selected an entry point which required the fuel cap to
be removed, then the cap would have to undergo a separate test as is
now done in many I/M stations.\309\ In this case, tests from both
points combined must pass the proposed emission standard.
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    \309\ For related information see ``IM240 & Evap Technical
Guidance'', EPA 420-R-00-007, April, 2000.
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    The procedure would be conducted as follows:
     Calibrate the testing apparatus and otherwise verify
testing apparatus is ready and able to complete the procedure
     Seal fuel system so as to pressure test entire system
(purge valve, cap, etc.)
     Attach test apparatus to vehicle's fuel system at selected
test point
     Pressurize fuel system with nitrogen or another inert gas
to at least 2.4 kilopascals (kPa)
     Allow flow and pressure to stabilize in accordance with
specification provided in the proposed regulatory text
     Calculate effective leak orifice diameter from measured
output flow rate and temperature and pressure data or use apparatus
with built in computer providing an equivalent digital readout.
Calculate to the nearest 0.01 inch.
     Calculated effective orifice diameter must be less than or
equal to the standard
     If leak test is conducted at the fuel cap then
manufacturer must also show evidence that the vehicle's fuel cap is
performing properly.\310\
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    \310\ Such tests are done routinely in I/M stations using a
commercially available apparatus. The gas cap leak rate may be
determined by pressure loss measurement, direct flow measurement, or
flow comparison methods and shall be compared to a pass/fail flow
rate standard of 60 cubic centimeters per minute of air at 30 inches
of water column. The flow rate methods are referenced to standard
conditions of 70[emsp14][deg]F and 1 atm.
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     EPA is seeking comment on requiring two separate test
points one near the evaporative canister and the other near the fuel
cap. Furthermore, we are specifically proposing that in some cases two
separate test points in the locations mentioned above would be
required. This would especially be important if the fuel cap/fill neck
area is isolated from the rest of the fuel/evaporative system as a
result of the 40 percent fill or if dual tanks are not otherwise
connected through vapor lines. Of course, dual tank, dual canister
systems would have to be evaluated as separate systems. Tests could be
void if the test apparatus fails, becomes disconnected, fails to
maintain a stable flow rate or pressure, or the test was stopped before
completion due to safety considerations or some other relevant vehicle
issue.
    The test procedure presented above is based on current fuel system
designs. In the future, it is reasonable to expect changes in designs
of the fuel systems such that the procedure above may need adjustment.
EPA would, of course, monitor these fuel system changes and modify the
test procedure provisions as needed. Furthermore, current EPA
regulations (see Sec.  1065.10(c)) contain provisions which provide the
opportunity for manufacturers to seek approval for special or alternate
test procedures if from a practical perspective their systems cannot be
evaluated under EPA requirements or they have an approach deemed
equivalent or better. EPA would make such provisions for the leak
emission standard testing requirement. Any such special or alternative
procedures would have to be reported under Sec.  86.004-21(b)(9).\311\
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    \311\ For example, MAHLE Powertrain has piece of equipment known
as a Mahle Leak Tester which is now used in assembly plants and may
be adaptable to this requirement.
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d. Proposed Onboard Diagnostic (OBD) System Regulation Changes
    EPA has its own OBD regulations which are similar but not identical
to CARB's. EPA first adopted OBD requirements for 1994 and later model
year LDVs and LDTs. While EPA has extended its requirements from LDVs
and LDTs to larger and heavier vehicles,\312\ EPA's last broad upgrade
to its basic OBD regulation was in the 2005 timeframe. Since that time,
CARB has adopted and the manufacturers have implemented a number of
provisions to enhance the effectiveness of their OBD programs. These
provisions include new requirements for OBD evaporative system leak
detection as well as provisions to help insure that systems are built
and operate as designed over their full useful life, give reliable
results (find and signal only true deficiencies), and operate
frequently during in use operation. It is permitted in current EPA
regulations and common practice for the industry to certify their OBD
systems with CARB and for EPA to accept CARB OBD certifications as
satisfying EPA requirements. EPA is proposing to continue that practice
but to upgrade our regulations to be consistent with the latest CARB
regulations.
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    \312\ EPA's OBD regulations for LDVs, LDTs, and MDPVs, are found
at 40 CFR 86.1806-05. EPA has also adopted OBD requirements for
incompletes and heavier vehicles (greater than 14,000 lbs GVWR) (see
74 FR 8324, February 24, 2009 and 40 CFR 86.010-18).
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    EPA has reviewed the current CARB regulatory requirements related
to OBD (see California Code of Regulations (CCR) Sec.  1968.2 dated May
18, 2010) and, as discussed below we are proposing to adopt most of
these provisions with the Tier 3 program. We are proposing this for two
basic reasons. First, this is consistent with the goal of a national
program and one vehicle technology for all 50 states. Second,
implementation of these requirements is now demonstrated technology and
compliance with these requirements is common within the industry today.
Thus, the added burden is minimal. Furthermore, OBD has the advantage
of running frequently on in-use vehicles to identify potential exhaust
and evaporative system performance problems, so adopting these
provisions would create the opportunity for OBD to serve a more
prominent role in ensuring the proposed Tier 3 emission standards are
met in-use.
    There is an important link between OBD provisions related to
evaporative emission control system leak monitoring and the proposed
leak test emission standard. They each provide an important incentive
to design fuel/evaporative systems with fewer propensities to develop
leaks in use but each addresses the issue from a different perspective.
The distinction is that the proposed leak emission standards prohibits
leaks of greater than 0.02 inches cumulative equivalent diameter, while
the proposed OBD evaporative system leak monitoring provision would
require that the OBD system find leaks larger than 0.020 inches
cumulative equivalent orifice diameter and notify the owner, but with
no inherent obligation to repair the problem. Thus adopting a 0.020
inch cumulative equivalent orifice diameter would align these two
programs and, as will be discussed below, creates the potential for an
optional leak detection test procedure for in-use testing.
    To be more specific, we are proposing to update our OBD regulations
to be

consistent with current California OBD requirements add two new
requirements and retain three minor exceptions. These changes would be
fully effective in the 2017MY, but EPA asks comment on whether the
requirement should be linked to be effective with certification to any
of the Tier 3 emission standards (either exhaust or evaporative) or
phased in for the 2017 model year for LDVs and LLDTs and the 2018 MY
for the HLDTs, MDPVs, and HDGVs up to 14,000 lbs GVWR.\313\ EPA would
continue to accept certifications with CARB OBD requirements as
satisfying EPA OBD requirements. We are proposing to incorporate by
reference section 1968.2 of the California Code of Regulations as
discussed below. This would include paragraphs (c) through (j) in their
entirety. These paragraphs are entitled: (c) Definitions, (d) General
requirements, (e) Monitoring requirements for gasoline/spark ignited
engines, (f) Monitoring requirements for diesel/compression ignition
engines, (g) Standardization requirements, (h) Monitoring system
demonstration requirements for certification, (i) Certification
documentation, (j) Production vehicle evaluation testing. The substance
of many of these provisions is already contained in current EPA OBD
requirements for LDVs, LDTs, MDPVs, and complete HDGVs less than 14,000
lbs GVWR.\314\
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    \313\ We are not proposing to change the requirement for
incompletes and vehicles with a GVWR above 14,000 lbs.
    \314\ MDVs in the CARB regulations basically incorporate MDPVs
and complete HDGV less than 14,000 lbs GVWR as defined by EPA.
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    The most noteworthy changes we are proposing are summarized below.
The CCR below is the California Code of Regulations cite for each
pertinent provision.
     EPA proposes to add a 0.020 inches leak detection
monitoring threshold upstream of the purge valve for all 4 vehicle
categories LDV, LDT, MDPV, and complete HDGVs up to 14,000 lbs GVWR
except for those with fuel tanks larger than 25 gallons capacity (see
CCR 1968.2(e)). OBD leak monitoring systems would have to identify,
store, and if required signal any leak(s) equal to or greater than
0.020 inches cumulative equivalent diameter. This would thus include
diagnostic trouble codes (DTC) P0440, P0442, P0446, P0455, P0456, and
P0457.
     EPA proposes to incorporate by reference the full array of
rate based monitoring requirements (see CCR1968.2 (d)). Meeting the
rate based monitoring requirements will help to insure that, even with
enable criteria, the exhaust and evaporative system monitors run
frequently enough that on average a problem would be identified and
signaled to the owner in operation within two weeks. This will help to
improve the fraction of time monitors are ready to find a potential
problem.
     EPA proposes to incorporate by reference provisions
regarding monitoring system demonstration requirements for
certification. We are proposing to incorporate by reference CARB
provisions in this area and to accept submissions to CARB for purposes
of compliance demonstration (see CCR 1968.2(h)). Adopting current CARB
monitoring system demonstration requirements assures that monitoring
systems operate as designed when installed on certification vehicles.
    We also propose that this certification include a requirement for
manufacturers to demonstrate the ability of the OBD leak monitoring
system to detect a 0.020 inch leak. Current CARB protocols do not
require that manufacturers demonstrate that the certification vehicle
can find a vapor leak in the fuel/evaporative system. We are proposing
to add a requirement that manufacturers must demonstrate for
certification that the OBD system can find and report the implanted
leak would help to ensure the OBD system's capability to function as
designed and for the OBD-based leak based evaporative system leak to be
used as an optional test procedure for in-use testing for the proposed
leak emission standard. We are proposing that this be added for the
same vehicles now required for monitoring system demonstration
requirements for certification under CARB OBD regulations. Since the
CARB regulation requires only a relative few vehicle models each year
per manufacturer, we propose that manufacturers be given the option to
either test the remainder for an implanted leak in the fuel/evaporative
system or certify by attestation that each of their remaining families
meets the requirement based on development and other information.
     EPA proposes to incorporate by reference the CARB
production vehicle evaluation data program. This program requires
manufacturers to demonstrate that the OBD system functions as designed
and certified when installed on production vehicles. (see CCR
1968.2(j))
     For the OBD evaporative system leak monitoring
requirement, EPA proposes a scan readable function (a new PID in
Service $01 of SAE J1979) which could be used to indicate or ascertain
the distance traveled since the OBD leak monitoring diagnostic was last
completed successfully and if the system passed or failed (identified
any leak above 0.020 inches) during that monitoring event (unless it is
otherwise already required in other OBD system modes). Updating this
PID this would be based on SAE J1979 mode 6 ($06) test results:
``Request On-board Monitoring Test Results for Specific Monitored
Systems.'' With this proposed requirement, the PID distance would be
initialized to maximum range of NV RAM initialization (such as battery
disconnect or controller reprogramming) and code clear. As a result, in
the event that a vehicle had a memory clear event in the past, but has
not had sufficient operation for the evaporative system to be
evaluated, the scan readable mileage function would indicate that the
system had not completed a full leak detection of the evaporative
control system within the last 750 miles (1200km). OBD systems already
maintain information for active, pending, historic and permanent codes.
This would be a modest upgrade to this requirement which would enable
the use of the OBD-based evaporative system leak monitor with the IUVP
program as discussed below. See CCR 1968.2 (g) for information related
to code storage. EPA seeks comment on alternative equivalent approaches
(e.g., a scan readable mileage stamp or flag traceable to mileage
indicating when the full OBD leak monitoring protocol was last
completed successfully and the result (p/f)) which accomplish the same
objective and whether this capability should be optional for the 2017
MY since this requirement is designed to enable the use of OBD in leak
emission standard testing and that standard is proposed to begin in the
2018 MY.
     The minor exceptions which are contained in EPA's current
OBD regulations are proposed to be continued. Compliance with 13 CCR
1968.2(d)(1.4), pertaining to tampering protection is not required.
Also, the deficiency provisions of 13 CCR 1968.2(k) would not be
adopted. In addition, demonstration of compliance with 13 CCR
1968.2(e)(15.2.1)(C), to the extent it applies to the verification of
proper alignment between the camshaft and crankshaft, would apply only
to vehicles equipped with variable valve timing. For all model years,
the deficiency provisions of paragraph (i) of the current regulations
apply only to alternative fuel vehicle/engine manufacturers selecting
this paragraph for demonstrating compliance.
    If adopted, these proposed changes, taken together would improve
the performance, reliability, general utility, and effectiveness of OBD
systems for Tier 3 exhaust and evaporative emission controls.
Furthermore, if adopted, these

changes create the opportunity for OBD evaporative system leak
monitoring systems to serve a more prominent role in ensuring
compliance with the leak emission standard. EPA believes that they
could be implemented for minimal cost since most manufacturers are
meeting them today and will have to for LEV III vehicles. However, EPA
requests comment on applying the proposed new OBD requirements to small
business vehicle manufacturers and independent commercial importers.
    As discussed below, the proposed OBD requirements would apply to
small entities and independent commercial importers (ICI) in the 2022
MY. Small alternative fuel converters would still be able to meet the
OBD requirements using the provisions of 40 CFR part 85 subpart F.
Finally, it should be noted that as CARB updates its OBD regulations in
the future EPA would consider these changes and propose to adopt them
or incorporate them by reference, if appropriate. In fact, CARB is
currently proposing some changes to its OBD program in response to the
LEV III program exhaust emission standards.\315\ We request comment on
incorporating these changes into this rule or other rules in the
future. We also would generally expect to continue the current practice
allowed by EPA regulations which is for EPA to accept CARB OBD
certifications as satisfying EPA requirements provided that they
include at least all of the requirements covered by the EPA
regulations.
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    \315\ CARB has recently proposed some minor OBD program
modifications in their recent LEVIII ISOR, and EPA asks for comment
on including those provisions within the proposed EPA OBD program.
See pages 61-72 of the CARB Staff Report at http://www.arb.ca.gov/regact/2012/leviiighg2012/levisor.pdf and pages A11-A125 of the
regulatory text at http://www.arb.ca.gov/regact/2012/leviiighg2012/levappa.pdf.
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e. In-Use Verification Program (IUVP) Requirements for the Leak
Emission Standard
i. Introduction
    We believe it is important to identify leaks since vehicles with
leaks would be expected to have daily emission rates above the proposed
Tier 3 evaporative emissions standards and the Colorado data suggests a
propensity for the diameter of vehicle leak orifice to get larger over
time and thus to have even higher emissions. This is also important
because evaporative leak emissions occur virtually every day whether
the vehicle is driven or not. Thus identifying potential leak problems
will be important to capturing the emission benefits of the proposed
evaporative emission requirements.
    Toward that end, EPA is proposing to include assessment of
compliance with the leak emission standard within the IUVP program. We
considered expanding the evaporative emission testing portion of the
IUVP program as a means to assess leaks, but we decided to focus on the
leak emission standard because it is less burdensome and is cost
effective for accomplishing the objective. EPA believes adding a leak
test requirement does not create an unreasonable burden. The draft test
procedure described above is simple to run, inexpensive to conduct in
terms of equipment and labor, and can be completed relatively quickly
compared to an evaporative emissions test. However, we are retaining
the evaporative emissions testing requirements currently in IUVP to
monitor broader evaporative control system effectiveness (e.g., purge,
canister control efficiency, permeation).
ii. IUVP Test Requirements
    We are proposing that the leak emission test be conducted for each
and every vehicle assessed in IUVP for exhaust emissions under 40 CFR
86.1845.04. This would begin for 2018 MY certifications for vehicle
families meeting the proposed new leak emission standard. This would
include the low and high mileage tests for any exhaust vehicle
evaluated for exhaust emissions plus a requirement that there be at
least one representative of each evaporative/refueling/leak family
evaluated at each year point. We are proposing this approach to
implementing IUVP for the leak emission standard in lieu of creating a
new set of requirements which would require yet another set of vehicles
to be procured for testing. We are not proposing to include the leak
test with any evaporative emissions test in IUVP, since a leak would be
evident in the results of the evaporative emissions test.
    The current IUVP regulations at Sec.  86.1845-04, Table S04-07,
call for test sample sizes on a sliding scale based on annual vehicle
sales by test group. This can vary from zero for very small sales test
groups to six vehicles for test groups with sales exceeding 250,000.
There are more exhaust emission test groups than there are evaporative/
refueling/leak test families and exhaust emission test groups may cover
one or more of the same evaporative/refueling/leak families, so we
would expect to receive multiple leak emission test results for most
evaporative/refueling/leak families. This will expand the amount of
IUVP data we receive in this important area and improve our ability to
assess the overall leak performance for a given evaporative/refueling/
leak family and the fleet as a whole.
    As discussed above, EPA believes that the fuel and evaporative
control system leaks are heavily influenced by age as well as design
and other factors. EPA would consider extending the age point for leak
emission testing for IUVP beyond the four year point to better assess
this effect. However, in the past, manufacturers have expressed concern
about the implications of testing older vehicles and about finding
vehicles still within their warranty and recall liability periods. EPA
asks comment on the viability of extending leak emission IUVP testing
beyond the nominal four year point (e.g., six to eight years). We
recognize that there are cost and vehicle procurement issues, but the
Colorado data strongly suggests a relationship between vehicle age and
the propensity for the development of leaks.
iii. Assessment of IUVP Leak Emission Standard Test Results
    The current regulations contain provisions addressing follow-on
testing requirements for exhaust emissions for vehicles which fail to
meet various performance thresholds within IUVP (see 40 CFR 86.1846-
01). As mentioned above, we expect that it will be common to get more
than one leak emission test result over the course of each model year's
mileage testing point for each evaporative/refueling/leak family as a
result of the requirement to assess leaks with each exhaust IUVP test.
However, the proposed leak emission standard is basically pass/fail at
0.02 inches and it is difficult to establish a threshold criteria for a
pass/fail standard such as has been done for exhaust emissions where
there is a multiplier applied to the level of the individual exhaust
emission standard.
    Given the importance of the leak emission standard in assuring in-
use evaporative emissions control, we are proposing a set of criteria
for assessing leak emission standard results from IUVP. These criteria
can be summarized as follows for each low and high mileage test point
for each model year tested:
     lf 50 percent or more of all vehicles evaluated in an
evaporative/refueling/leak emission family for any given model year
pass the leak emission standard, testing is complete. This applies to
cumulative testing for that family throughout the model year for that
mileage group. This is consistent with the exhaust emission
requirements for IUVP and EPA believes it is reasonable since vehicles
are tested in the ``as received'' condition from consumers.

     If only one representative of the evaporative/refueling/
leak family is tested in a mileage group for that model year's vehicles
and it passes the leak emission standard testing is complete. If that
vehicle does not pass the leak emission standard a manufacturer may
test an additional vehicle to achieve the 50 percent rate.
     If an evaporative/refueling/leak emission family fails to
achieve the 50 percent rate, it is presumed that the family will enter
into In-Use Confirmatory Testing Program (IUCP).
    Before IUCP begins, the manufacturer may ask for engineering
analysis discussions with EPA to evaluate and understand the technical
reasons for the testing outcomes and the implications for the broader
fleet. Technical information for these discussions could include but
would not be limited to detailed system design, calibration, and
operating information, technical explanations as to why the individual
vehicles tested failed the leak emission standard, and comparisons to
other similar families from the same manufacturer. Relevant information
from the manufacturer such as data or other information on owner
complaints, technical service bulletins, service campaigns, special
policy warranty programs, warranty repair data, state I/M data, and
data available from other manufacturer specific programs or initiatives
could help inform understanding of implications for the broader fleet.
As part of this process a manufacturer could elect to provide
evaporative emissions SHED test data on the individual vehicle(s) that
did not pass the leak emission standard during IUVP. With an adequate
technical basis, the outcome of this engineering analysis discussion
could result in an EPA decision not to require IUCP testing.
    We would propose to operate within the basic structure of the IUCP
program in the current regulations. Prior to commencing IUCP testing
the manufacturer, after consultation with EPA submits a written plan
describing the details of the vehicle procurement, maintenance, and
testing procedures. This plan could include inclusion of a hot soak
plus diurnal SHED test to supplement leak emission test results. We
propose that EPA must approve this plan before testing begins. As
prescribed now in the IUCP regulations for exhaust, if five vehicles
were tested and all passed the leak emission standard then testing
would be complete. If all five vehicles did not pass, then five more
would be tested. More vehicles could be tested at the manufacturer's
discretion but all testing would have to be completed within the time
period specified in the regulations today. EPA and the manufacturer
would then enter into discussions regarding interpretation, technical
understanding, and compliance/enforcement implications of the test
results, if any.
iv. Proposed Optional Test Procedure Approach for IUVP/IUCP
    Assuming implementation of the OBD regulation changes proposed in
Section IV.C.5.d, above, EPA is proposing an optional approach to a
portion of the leak emission test procedure discussed in Section
IV.C.5.c. This optional testing approach would be included in the
proposed IUVP/IUCP testing program for the leak emission standard, but
would not be used for certification testing for the leak emission
standard. It would be considered an approach which could be used by the
manufacturers to assess compliance with the leak emission standard. EPA
could also use this procedure for conducting assessments and asks for
comment on using this procedure for compliance purposes with a 0.02
inch cumulative equivalent diameter orifice standard.
    Under this optional approach manufacturers would be able to rely
upon the operation of their OBD evaporative system leak detection
hardware and operating protocols in lieu of running the stand alone in-
use leak test to check for the presence of a 0.02 inch leak in the
fuel/evaporative system. This approach relies on the leak emission
standard equivalent orifice diameter being established at the same
level as proposed for OBD (0.020 inches). Thus, the IUVP/IUCP protocol
would be modified and simplified to expedite completion of testing and
reduce costs.
    Quite simply, if a vehicle is brought in for IUVP or IUCP testing
and a scan tool query of the onboard computer indicates that the
vehicle had successfully completed a full OBD-based evaporative system
leak monitoring check within the last 750 miles and no evaporative
system leak problems for any diameter above 0.020 inches was indicated
(diagnostic trouble codes P0440, P0442, P0446, P0455, P0456, and
P0457), the vehicle would be been deemed to have met and passed the
leak emission standard test requirement. However, if the system had not
successfully completed a full OBD-based evaporative system leak check
within 750 miles with no problem indicated then the manufacturer would
have the option to run its OBD-based evaporative system leak check in
the laboratory after prescribed preconditioning. This OBD-based
approach is sometimes used in auto manufacturer dealerships and repair
facilities to diagnose and fix evaporative system leaks found by the
OBD system. If the vehicle completes the full OBD-based leak test in
the laboratory then the vehicle's pass/fail results for the 0.02 inch
cumulative equivalent diameter orifice would be based on the OBD test
result. This optional protocol could apply to every leak emission
standard test after certification unless not approved by EPA for IUCP
under 40 CFR 1846.01(i). Replicate tests would not be required or
allowed but void tests could be repeated.
    Furthermore, EPA proposes to allow the manufacturer to run the
stand alone EPA leak test in several situations. First, manufacturers
could conduct the stand alone test to confirm that a problem identified
by the OBD-based evaporative system monitoring leak check was a leak
and not a problem with the OBD leak monitor itself. Second, a
manufacturer could run the stand alone EPA leak test to confirm that
the leak value identified by the OBD system was truly above the level
of the proposed leak emission standard. Third, it could be used for
vehicles which had not successfully completed a full OBD-based
evaporative system leak monitoring check within the last 750 miles.
Fourth, it could be used to confirm that a DTC set within the last 750
miles actually indicated the presence of a leak(s) greater than the
proposed standard. However, if a manufacturer elected to use only OBD-
based evaporative system leak based monitoring in its IUVP testing;
these results would be the basis for decisions regarding IUCP. As is
required in the current IUVP regulations, all test data whether OBD
based or based on EPA's stand alone test procedure would have to be
reported to EPA.
    There could be some advantages to this option since it employs a
pressure/vacuum approach manufacturers understand and creates positive/
negative pressures manufacturers have accommodated within their fuel/
evaporative system. One potential downside is that under current
designs vehicle engines would have to be operating to create the
pressure or vacuum and because the engine is operating this would
require the OBD-based leak test to be stand alone after the
preconditioning sequence is complete. This would be more challenging
for natural vacuum leak detection systems unless extended driving was
involved to create the fuel system heat needed for a natural vacuum
event or this was done through a climate chamber or SHED based diurnal
heat build.

    Allowing for this approach raises at least two implementation
questions. The first is related to the value of conducting the OBD-
based test for a vehicle with an active or pending leak DTC already set
in the computer and/or an MIL indicated. In this case, EPA would permit
the manufacturer to run the OBD-based leak test and/or the stand alone
EPA leak test or concede that the vehicle would not pass the leak
emission standard and count the result. Second is the question of gas
caps. This is among the most common codes found in OBD records and is
often related to operator error such as not tightening the gas cap
properly. Codes of this nature have no value in this leak emission
assessment, so a manufacturer would be permitted to correct the problem
before testing and clear this OBD code before testing or run the stand
alone EPA leak test.
6. Other Initiatives
    This proposal includes consideration of several amendments or
clarifications to existing requirements related to evaporative
emissions. As part of this process, the following provisions warrant
adjustment, clarification, or correction:
     Even though the evaporative emission standards in 40 CFR
part 86 apply to the same engines and vehicles that must meet exhaust
emission standards, we require a separate certificate for complying
with evaporative and refueling emission standards. An important related
point to note is that the evaporative and refueling emission standards
always apply to the vehicle, while the exhaust emission standards may
apply to either the engine or the vehicle. Since we plan to apply
evaporative/refueling/leak emission standards and the recently adopted
greenhouse gas standards to vehicle manufacturers, we believe it would
be advantageous to have the regulations related to their certification
requirements written together as much as possible to reduce burden and
increase efficiency. We are therefore proposing to move the emission
standards and certification requirements from 40 CFR part 86 to the new
40 CFR part 1037, which was originally used for greenhouse gas
standards for heavy-duty highway vehicles. This is not intended to
change the requirements that apply to these vehicles, except as noted
in this section. We propose to make the provisions in part 1037
effective with model year 2014.
     As described in Section VI.C.3, we are proposing to allow
for certifying vehicles above 14,000 lbs GVWR based on an engineering
analysis instead of new testing (as is currently allowed for vehicles
at or above 26,000 lbs GVWR). We are also proposing to clarify the
provisions describing how the certification process plays out for these
vehicles.
     Section 86.1810-01 contains specifications addressing
whether diesel fuel vehicles can be waived from demonstrating
compliance with the refueling emission standard through testing. In the
current regulation the potential for a waiver from testing depends on
the diesel fuel having an RVP equal to or less than 1 psi and the fuel
tank having a temperature which does not exceed 130[emsp14][deg]F. We
have examined this provision and are proposing to withdraw the fuel
temperature limit specification. Short of fuel spillage in the SHED,
EPA sees no likelihood that a diesel fueled vehicle with RVP less than
1 psi could fail the refueling emission standard even at fuel tank
temperatures above 130[emsp14][deg]F. This is due to the inherently low
vapor pressure of diesel at these temperatures and the likelihood that
vapor shrinkage conditions will occur in the fuel tank during refueling
since the dispensed fuel will be cooler than the tank fuel.
     When adopting the most recent evaporative emission change
we did not carry through the changes to the regulatory text applying
evaporative emission standards for methanol-fueled compression-ignition
engines. The proposed regulations correct this oversight.
     We are proposing provisions to address which standards
apply when an auxiliary (nonroad) engine is installed in a motor
vehicle, which is currently not directly addressed in the highway
regulation. The proposed approach would require testing complete
vehicles with any auxiliary engines (and the corresponding fuel-system
components). Incomplete vehicles would be tested without the auxiliary
engines, but any such engines and the corresponding fuel-system
components would need to meet the standards that apply under our
nonroad program as specified in 40 CFR part 1060.
     We are proposing to remove the option for secondary
vehicle manufacturers to use a larger fuel tank capacity than is
specified by the certifying manufacturer without re-certifying the
vehicle. Secondary vehicle manufacturers needing a greater fuel tank
capacity would need to either work with the certifying manufacturer to
include the larger tank, or go through the effort to re-certify the
vehicle itself. Our understanding is that this provision has not been
used and would be better handled as part of certification rather than
managing a separate process. We are proposing corresponding changes to
the emission control information label.
     Since we adopted evaporative emission standards for
gaseous-fuel vehicles, we have developed new approaches for design-
based certification (see, for example, 40 CFR 1060.240). We request
comment on changing the requirements related to certifying gaseous-fuel
vehicles to design-based certification. This would allow for a simpler
assessment for certifying these vehicles without changing the standards
that apply.
     With regard to OBD, we note also that under Sec.  86.1806-
01(b)(4) OBD systems must have the ability to detect absence of purge
air flow from a complete evaporative emission control system. This is
clearly important because the proper operation of an integrated
evaporative/refueling emission control system depends on purge.
Similarly, evaporative/refueling system operation depends on the
presence, proper adsorption/desorption performance, and sustained
working capacity of the activated carbon canister. It is thus curious
to observe that the current OBD provisions do not directly address the
activated carbon canister in any way. The absence of the canister would
likely be noted as a gross leak and/or a problem with purge.
Nonetheless, we are seeking comment on a provision which would require
the OBD system to sense for evidence of ongoing adsorption and
desorption of hydrocarbon vapors. These could both be sensed by changes
in canister carbon bed temperature or perhaps for the presence of vapor
in the fuel going to the intake manifold after a cold start or
refueling event. In some cases, EPA believes these parameters could be
monitored by hardware and sensors now on most vehicles and thus this
might be primarily an OBD software change. Similarly, we are seeking
comment on whether the operation of a vacuum pump or similar device
used to assist or supplement vehicle engine vacuum purge or any device
otherwise used to enhance or control purge flows, rates, or schedules
should be required to be monitored as part of OBD.
     With future technology, we anticipate a trend toward the
implementation of fuel tanks with higher operating pressures and in
some cases fuel tanks which are sealed to the atmosphere during normal
operation. Data available to EPA indicates that a leak in such a system
will result in substantial emissions relative to very low pressure
systems which employ running loss control strategies and an activated
carbon canister as part of the

methodology to control vapor emissions.\316\ Based on this concern, we
are seeking comment on the feasibility and cost of requiring the OBD
leak detection monitoring system to detect and signal the presence of a
smaller diameter orifice than proposed for non-pressurized systems (~
0.010 inch) upstream of the purge valve for all 4 vehicle categories
LDV, LDT, MDPV, and complete HDGVs up to 14,000 lbs GVWR. This would
apply to any vehicle with a designed in-use operating pressure in
excess of 0.36 psi (10 inches water). As a means to prevent a sealed
fuel tank from venting leaks directly to atmosphere, we ask for comment
on an added requirement that the fuel vapor vent valve be set to the
open position at key off (and vent to the canister) if the OBD system
detected a leak and triggered an MIL related to any leak greater than a
pre-established threshold. The vent open at key off concept for
pressurized fuel systems would not be intended to disenable the OBD
system from conducting its normal evaporative system check during
operation. Furthermore, as discussed above, we are proposing a 0.020''
leak detection threshold for all systems. However, we are asking for
comment on setting the threshold in the 0.010''-0.015'' range for
pressurized systems. In the context of this request for comment, we ask
for input regarding the feasibility of the smaller threshold, the
effects of the vent valve open requirement on ORVR, and the
repairability of leaks of less than 0.020''.
---------------------------------------------------------------------------

    \316\ Passavant, G. (February 2013). Presentation on Evaporative
Emission System Leaks for a Fuel Tank Under Pressure. Memorandum to
the docket.
---------------------------------------------------------------------------

D. Emissions Test Fuel

1. Proposed Changes to Gasoline Emissions Test Fuel
    In-use gasoline has changed considerably since EPA's fuel
specifications for emissions testing of light- and heavy-duty gasoline
vehicles were first set and last revised. Gasoline sulfur and benzene
have been reduced and, perhaps most importantly, gasoline containing 10
percent ethanol by volume (E10) has replaced clear gasoline (E0) across
the country. This has had second-order effects on other gasoline
properties. In-use fuel is projected to continue to change with the
implementation of the RFS2 program (e.g., the expansion of the number
of retailers that offer E15) as well as today's proposed Tier 3
gasoline sulfur program. As a result, we are proposing to update our
federal emission test fuel specifications not only to better match
today's in-use fuel but also to be forward looking with respect to
future ethanol and sulfur content.\317\ The revised test fuel
specifications would apply for exhaust emissions testing, fuel economy/
greenhouse gas testing, and emissions testing for non-exhaust emissions
(evaporative, refueling, and leak detection testing). The proposed
gasoline specifications, found at Sec.  1065.710, would apply to
emissions testing of light-duty cars and trucks as well as heavy-duty
gasoline vehicles certified on the chassis test, those subject to the
proposed Tier 3 standards.\318\
---------------------------------------------------------------------------

    \317\ EPA's motor vehicle emissions standards typically require
a level of performance over a specified test procedure, with
emissions measured while the engine or the vehicle is operated using
the specified test fuel and operated in a specified manner. The test
fuel specifications typically apply for all emissions testing used
to determine compliance with the standard, including emissions
testing to obtain a certificate of conformity, as well as compliance
testing for newly produced or in-use engines or vehicles. While this
test fuel is commonly referred to as ``certification fuel,'' the
test fuel specifications proposed today are not limited to
certification related emissions testing, but also apply to
compliance related emissions testing after the certificate of
conformity has been issued. The certification process also typically
involves a process to ensure that the emissions controls system is
durable over the regulatory useful life of the vehicle or engine.
This can involve long-term or accelerated aging of a vehicle or
engine prior to emissions testing. The fuel used for such aging is
commonly referred to as service accumulation or durability fuel, and
in many cases is specified as commercial gasoline that will be
generally available through retail outlets (Sec.  86.113-04(a)(3)),
or in some cases may be specified as gasoline which contains ethanol
in, at least, the highest concentration permissible in gasoline
under federal law and that is commercially available in any state in
the United States, such as for durability aging of evaporative
emissions system (Sec.  86.1824-08(f)). EPA is not proposing changes
to the specifications for fuel used during durability related aging
that is part of the certification process. The proposed changes only
apply to the test fuel used during emissions testing, both for
purposes of certification and for later compliance related testing.
    \318\ As discussed in Section IV.C, we are also seeking comment
on requiring the proposed Tier 3 test fuel in conducting exhaust,
evaporative, and refueling emissions testing of heavy-duty gasoline
engines certified on an engine dynamometer. These could include
engines installed in incomplete Class 2b and Class 3 vehicles and
engines used in vehicles above 14,000 lb GVWR.
---------------------------------------------------------------------------

    We are not proposing changes to the exhaust or evaporative
durability fuel requirements outlined in the provisions of Sec.
86.113-04(a)(3), except to remove the minimum sulfur content (15 ppm)
currently specified at Sec.  86.113-04(a)(3)(i). Those provisions
require that ``Unless otherwise approved by the Administrator, unleaded
gasoline representative of commercial gasoline that will be generally
available through retail outlets must be used in service
accumulation.'' We would expect that manufacturers would use service
accumulation fuels which are generally representative of the national
average in-use fuels (or worst case for durability) during the model
year which is being certified, including, for example, the ethanol
content (for exhaust emissions), sulfur level, and fuel additive
package. For exhaust emission bench aging durability programs as
allowed under the provisions of Sec.  86.1823-08(d) and (e), the bench
aging program should be designed using good engineering judgment to
account for the effects of in-use fuels on exhaust emissions, including
the effects of future in-use fuels on catalytic converters, oxygen
sensors, fuel injectors, and other emission-related components.
    For evaporative emissions, durability fuel requirements are the
same as for exhaust emissions (as outlined above), plus an additional
requirement in the provisions of Sec.  86.1824-08(f), that the service
accumulation fuel ``contains ethanol in, at least, the highest
concentration permissible in gasoline under federal law and that is
commercially available in any state in the United States. Unless
otherwise approved by the Administrator, the manufacturer must
determine the appropriate ethanol concentration by selecting the
highest legal concentration commercially available during the calendar
year before the one in which the manufacturer begins its mileage
accumulation.'' Thus, as E15 in-use fuel becomes progressively more
available, we would expect that E15 service accumulation fuel would be
used for whole vehicle evaporative durability programs. Similarly,
evaporative bench aging durability programs allowed under the
provisions of Sec.  86.1824-08(d) and (e), should be designed using
good engineering judgment to account for the durability effects of in-
use fuels on evaporative emissions, bleed emissions, and leakage
emissions.
    Where possible, we are proposing changes consistent with the CARB's
planned LEV III gasoline test fuel specifications.\319\ Below is an
overview of some of the key changes. A summary of the proposed test
fuel specifications is provided in Table IV-21. For more information on
how we arrived at the proposed test fuel property ranges and ASTM test
methods, refer to Chapter 3 of the draft RIA.
---------------------------------------------------------------------------

    \319\ The LEV III program as approved by the California Air
Resources Board, January 2012.
---------------------------------------------------------------------------

     Ethanol--adding a 15 volume percent ethanol specification
to be forward-looking with respect to the maximum gasoline ethanol
concentration Tier 3 vehicles could expect to encounter. EPA recently
issued a waiver under section 211(f)(4) of the CAA permitting E15 to be

introduced into commerce for use in MY2001 and newer light-duty motor
vehicles.\320\ While E15 is only commercially available at a limited
number of fuel retailers, EPA believes it could become a major gasoline
blend over the next 10-15 years given instability in crude oil pricing
and growing RFS2 renewable fuel requirements. The use of E15 as the
emission test fuel will help ensure that all future vehicles are
capable of meeting Tier 3 emission standards while operating on E15.
---------------------------------------------------------------------------

    \320\ On Nov. 4, 2010, EPA issued a partial waiver for MY2007
and newer light-duty motor vehicles (75 FR 68094). On January 26,
2011, EPA extended the waiver to MY 2001-2006 light-duty motor
vehicles (76 FR 4662).
---------------------------------------------------------------------------

     Octane--lowering gasoline octane to around 87 (R+M)/2 to
be representative of in-use fuel, i.e., regular-grade gasoline.
Manufacturers could continue to use high-octane gasoline for testing of
premium-required \321\ vehicles and engines as well as for testing
unrelated to exhaust emissions. Historically, the high octane rating of
test fuel has not had any real emissions implications. However, as
manufacturers begin introducing new advanced vehicle technologies
(e.g., turbocharged downsized), this may no longer be the case. For
those vehicles where operation on high-octane gasoline is required by
the manufacturer, we would allow the manufacturer to test on a fuel
with a minimum octane rating of 91 (R+M)/2 (in lieu of the proposed 87
(R+M)/2 general test fuel). According to the proposed regulations found
at Sec.  1065.710(d), vehicles or engines are considered to require
premium fuel if they are designed specifically for operation on high-
octane fuel and the manufacturer requires the use of premium gasoline
as part of their warranty as indicated in the owner's manual. Cases
where premium gasoline is not required but is recommended to improve
performance would not qualify as a vehicle or engine that requires the
use of premium fuel. For qualifying vehicles and engines, all emission
tests must use the specified high-octane fuel. For vehicles and engines
certified on high-octane gasoline, all EPA confirmatory and in-use
testing would also be conducted on high-octane gasoline. All other test
fuel specifications would be the same as those proposed in Table IV-21.
We seek comment on the need for limiting the maximum octane of gasoline
used in the certification of premium-required engines and vehicles.
---------------------------------------------------------------------------

    \321\ Premium-required defined at Sec.  1065.710(d).
---------------------------------------------------------------------------

     Distillation Temperatures--adjusting gasoline distillation
temperatures to better reflect today's in-use gasoline/E10. This
includes minor T10, T90 and FBP adjustments based on AAM in-use fuel
surveys and refinery batch test data, with additional adjustments to
reflect future E15 performance (significantly lower T50 range). We seek
comment on the appropriateness of the proposed distillation
temperatures including the proposed 170-190[emsp14][deg]F T50 range for
an E15 fuel. For more information on how we arrived at the proposed
distillation temperatures in Table IV-21, refer to Chapter 3 of the
draft RIA.
     Sulfur--lowering the sulfur content of test fuel to 8-11
ppm to be consistent with our proposed Tier 3 gasoline sulfur
standards. The proposed 10-ppm annual average sulfur standard is
expected to result in two-thirds less sulfur nationwide so it is
appropriate to lower the gasoline test fuel specification in concert.
     Benzene--setting a benzene test fuel specification of 0.6-
0.8 volume percent to represent in-use fuel under our new MSAT2
regulations.\322\ The MSAT2 standards, which took effect January 1,
2011, limit the gasoline pool to 0.62 volume percent benzene on
average. Beginning July 1, 2012, no refinery may produce gasoline above
1.3 volume percent benzene on average.
---------------------------------------------------------------------------

    \322\ 72 FR 8434 (February 26, 2007).
---------------------------------------------------------------------------

     Total Aromatics--lowering the aromatics content of test
fuel to better match today's in-use gasoline/E10 and accommodate E15.
According to AAM fuel surveys, the average aromatics content in
gasoline has dropped 16 percent over the past decade due to ethanol
blending.\323\ Additional ethanol blending to produce E15 is expected
to result in even greater aromatics reductions. Accordingly, we believe
the proposed 19.5-24.5 volume percent test fuel specification is
appropriate.
---------------------------------------------------------------------------

    \323\ For more information on current aromatics levels, refer to
Chapter 3 of the draft RIA.
---------------------------------------------------------------------------

     Distribution of Aromatics--in addition to total aromatics
and benzene, we are proposing regulations that would require a
distribution of aromatics (i.e., a certain amount of C7, C8, C9, and
C10+ hydrocarbons) to ensure that test fuel is more representative of
in-use gasoline. Heavier aromatics in gasoline are believed to
contribute to vehicle PM emissions, so it is important that vehicles
are designed to meet the proposed Tier 3 emission standards on fuel
with a distribution of aromatic compounds representative of in-use
gasoline. We also seek comment on the need for a multi-substituted
alkyl aromatics (MSAA) specification, as has been proposed by CARB. For
more information on our proposed aromatics specifications, refer to
Chapter 3 of the draft RIA.
     Olefins--adjusting the olefins specification to better
match today's in-use gasoline/E10 according to AAM fuel surveys. Not
only is the proposed 4.5-11.5 mass percent range (approximately 4-6
volume percent) more representative of in-use fuel, the narrower test
fuel range would result in more consistent vehicle test results.
     Other Specifications--adding distillation residue, total
content of oxygenates other than ethanol, copper corrosion, solvent-
washed gum, and oxidation stability specifications to better control
other performance properties of test fuel. These proposed
specifications are consistent with ASTM's D4814 gasoline specifications
and CARB's LEV III test fuel requirements.
     Updates to Gasoline Test Methods--updating some of the
gasoline test methods currently specified in Sec.  86.113 with more
appropriate, easier to use, or more precise test methods for ethanol-
blended gasoline. Key changes include replacement of ASTM D323 with
ASTM D5191 for measuring vapor pressure; replacement of ASTM D1319 with
ASTM D5769 for measuring aromatics and benzene; and replacement of ASTM
D1266 with three alternative ASTM test methods (D2622, D5453 or D7039)
for measuring sulfur. We request comment on the use of three different
test methods for the measurement of sulfur content.
     Consolidation of Test Fuels--consolidation of all gasoline
exhaust and evaporative emission test fuels into a single general test
fuel. This would be used for all on-highway vehicle testing with the
exception of cold CO vehicle testing (which would use higher volatility
test fuel) and high-altitude testing (which would be permitted to use
lower volatility fuel). As discussed above, commercial gasoline would
continue to be used for service accumulation (durability fuel). This is
consistent with CARB's LEV III approach and should help limit the total
number of test fuels that automakers need to manage.

                                                   Table IV-21--Proposed Gasoline Emissions Test Fuel
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                              Specification
                                                      -------------------------------------------------------------
            Property                      Unit                            Low-temperature                                 ASTM reference procedure
                                                        General testing       testing       High altitude testing
--------------------------------------------------------------------------------------------------------------------------------------------------------
Antiknock Index (R+M)/2.........  ...................              87.0--88.4              87.0 Minimum...........  D2699-11 and D2700-11.
--------------------------------------------------------------------------------------------------------------------------------------------------------
,nSensitivity (R-M).............  ...................                          7.5 Minimum
--------------------------------------------------------------------------------------------------------------------------------------------------------
Dry Vapor Pressure Equivalent     kPa (psi)..........         60.0-63.4         77.2-81.4  52.4-55.2..............  D5191-10b.
 (DVPE).                                                      (8.7-9.2)       (11.2-11.8)  (7.6-8.0)..............
--------------------------------------------------------------------------------------------------------------------------------------------------------
Distillation
    10% evaporated..............  [deg]C ([deg]F)....             49-60             43-54  49-60..................  D86-10a.
                                                              (120-140)         (110-130)  (120-140)..............
--------------------------------------------------------------------------------------------------------------------------------------------------------
    ,n50% evaporated............  [deg]C ([deg]F)....                        77-88 (170-190)
    90% evaporated..............  [deg]C ([deg]F)....                       154-166 (310-330)
    Evaporated final boiling      [deg]C ([deg]F)....                       193-216 (380-420)
     point.
Residue.........................  Milliliter.........                          2.0 Maximum
--------------------------------------------------------------------------------------------------------------------------------------------------------
Total Aromatic Hydrocarbons.....  vol. %.............                           19.5-24.5                           D5769-10.
--------------------------------------------------------------------------------------------------------------------------------------------------------
    ,nC6 Aromatics (benzene)....  vol. %.............                            0.6-0.8
    C7 Aromatics (toluene)......  vol. %.............                            4.4-5.5
    C8 Aromatics................  vol. %.............                            5.5-6.9
    C9 Aromatics................  vol. %.............                            5.0-6.2
    C10+ Aromatics..............  vol. %.............                            4.0-5.0
--------------------------------------------------------------------------------------------------------------------------------------------------------
Olefins.........................  mass %.............                            4.5-11.5                           D6550-10.
Ethanol.........................  vol. %.............                           14.6-15.0                           D5599-00 (Reapproved 2010).
--------------------------------------------------------------------------------------------------------------------------------------------------------
,nTotal Content of Oxygenates     vol. %.............                          0.1 Maximum
 Other than Ethanol.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Sulfur..........................  mg/kg..............                            8.0-11.0                           D2622-10, D5453-09 or D7039-07.
Lead............................  g/liter............                         0.0026 Maximum                        D3237-06.
Phosphorus......................  g/liter............                         0.0013 Maximum                        D3231-11.
Copper Corrosion................  ...................                         No. 1 Maximum                         D130-10.
Solvent-Washed Gum Content......  mg/100 ml..........                          3.0 Maximum                          D381-09.
Oxidation Stability.............  Minute.............                         1,000 Minimum                         D525-05.
--------------------------------------------------------------------------------------------------------------------------------------------------------

    EPA seeks comment on the appropriateness of the proposed forward-
looking E15 test fuel for light- and heavy-duty gasoline vehicles.
While we believe we have discretion under the statute to transition
from E0 to E15 test fuel, we acknowledge that vehicle manufacturers
will need to calibrate their vehicles to meet the proposed Tier 3
standards on fuel containing 15 percent ethanol by volume. Our analysis
of the proposed Tier 3 standards (emission control technology,
feasibility, cost, etc.) assumes the use of the proposed E15 test fuel.
We anticipate that vehicle electronic control systems will be fully
capable of adjusting to maintain emission performance when operating on
E10 (or any remaining E0), but if E15 were not to enter the gasoline
pool in significant quantities, it may be more appropriate to require
that vehicles be calibrated for and tested on E10.
    We are seeking comment on various alternative approaches, e.g.,
starting with E10 as the test fuel and transitioning to E15 as the
market further transitions to E15 in use. This could include a market
review in 2014 or 2015 followed by regulatory action to implement the
change from E10 to E15 test fuel, if warranted. Or, it could include
the establishment of a ``trigger point'' (e.g., 30 percent of gasoline
is E15) in the Tier 3 final rule to prompt an automatic move to E15
after a certain period of time, e.g., two or three years. Or, we could
simply set a future date (e.g., 2020) with sufficient time for
transitioning to E15 test fuel. These transition approaches would give
vehicle manufacturers additional lead time to prepare for higher
ethanol concentrations in test fuel. We seek comment on the various
transition approaches, their timing, and the appropriate specifications
for an E10 test fuel to be used in the interim.
    While the volatility (i.e., RVP) of CARB's E10 test fuel is 7.0 psi
to be representative of in-use gasoline in California during summer
months, conventional E10 in the rest of the country is currently around
10 psi. Thus, should we finalize E10 instead of E15, in the absence of
any standard to reduce the in-use RVP of E10 to 9.0 psi or lower, we
would also have to consider raising the RVP of certification test fuel
to 10 psi to reflect the RVP level of the current in-use fuel. Were we
to raise the volatility to 10 psi RVP, EPA believes that the proposed
evaporative emission standards would be feasible, but this would
increase the stringency of the proposed evaporative emission standards
(see Section IV.C). Changing certification test fuel to 10 psi RVP
would increase vapor generation rates during the refueling test by
about 10 percent and during the hot soak, diurnal, canister bleed, and
running loss tests by as much as 25 percent in total. To the extent
that the refueling test dictates the size of the canister, the
increased vapor generation would necessitate increases in the volume of

activated carbon used in the vehicle's onboard canister by about 10
percent. Perhaps more importantly, manufacturer's vehicle purge
strategies and technologies would likely have to be modified to
removing the larger vapor loads from the canister during vehicle
operation. Some vehicles have adequate engine vacuum available to
provide the increased purge, while others may require new or innovative
approaches to increase purge volume or canister purge efficiency as
discussed in the evaporative emissions technology discussion. While we
have not performed a detailed analysis, EPA estimates that on average
the evaporative standard compliance costs could be about $10-15 per
vehicle higher at 10 psi RVP compared to 9 psi RVP for canister and
purge upgrades. With respect to lead time, EPA's current proposal calls
for either 40 percent of light-duty vehicles to meet the Tier 3
evaporative emission standards in 2017 MY (percentage option) or for a
manufacturer to sell only zero evap PZEVs nationwide (PZEV only
option). This basic approach for 2017 could still be feasible depending
on the resolution of the test procedure issues and proposed
flexibilities in phase-in schemes.
    Raising the certification test fuel to 10 psi RVP would also impact
the equivalency of CARB and EPA refueling and hot soak plus diurnal
evaporative emission test procedures. These potential impacts would
have to be addressed to maintain CARB/EPA evaporative emissions test
reciprocity. Furthermore, there may be test procedure options for
minimizing the burden of changing certification test fuel RVP while
maintaining the needed in-use control.
    EPA does not believe that a 10 psi certification test fuel would
impact the feasibility or cost of the proposed leak emission standard
or the proposed change in the OBD evaporative system leak detection
requirements, since these are based on orifice diameter. Nor, do we
believe that it would have any negative impact on permeation emissions
or exhaust emissions.
    As mentioned above, EPA issued a waiver allowing E15 to be
introduced into commerce for use in MY 2001 and newer light-duty motor
vehicles. On July 25, 2011, EPA finalized regulations to mitigate the
potential for misfueling of vehicles, engines, and equipment not
covered by the E15 waiver, i.e., MY 2000 and older light-duty motor
vehicles, all heavy-duty gasoline vehicles and engines, motorcycles,
and all gasoline-powered nonroad products (which includes boats).\324\
Two of the required mitigation measures are a label for fuel pumps that
dispense E15 to alert consumers to the appropriate and lawful use of
the fuel and a prohibition on the use of E15 by consumers in vehicles
not covered by the waiver, excluding flexible fuel vehicles (FFVs). If,
as discussed in this proposed rule, any class of new heavy-duty
gasoline vehicles or engines begin testing on E15 for certification,
EPA would not need to issue a waiver under section 211(f)(4) to allow
introduction of E15 into commerce for use in these vehicles certified
on E15 test fuel. However, EPA acknowledges that changes to the
gasoline pump label and prohibitions finalized in the E15 Misfueling
Mitigation Measures Rule would have to be made before E15 could
lawfully be sold for use in these heavy-duty vehicles. This would be
addressed in a future action.
---------------------------------------------------------------------------

    \324\ 76 FR 44406 (July 25, 2011).
---------------------------------------------------------------------------

    As discussed above in Sections IV.A.7.c (tailpipe emission testing)
and IV.C.4.b (evaporative emission testing), we are proposing to
require certification of all Tier 3 light-duty and chassis-certified
heavy-duty gasoline vehicles on E15 test fuel. As described in those
sections, we are proposing that EPA still accept testing for
certification on CARB's E10 test fuel during the phase-in periods for
the respective proposed Tier 3 vehicle tailpipe and evaporative
emissions standards and, if certified on CARB's E10 test fuel, that EPA
would not perform or require in-use exhaust or evaporative testing on
E15 test fuel.
    As mentioned earlier, we plan to continue to allow manufacturers to
test vehicles on premium-grade gasoline should the vehicles require it.
Since we cannot predict all future changes in gasoline vehicle
technologies and in-use fuels, we are proposing to allow vehicle
manufacturers to specify an alternative test fuel under certain
situations. Under this proposal, if manufacturers were to design
vehicles that required operation on a higher octane, higher ethanol
content gasoline (e.g., dedicated E30 vehicles or FFVs optimized to run
on E30 or higher ethanol blends), under 40 CFR 1065.701(c), they could
petition the Administrator for approval of a higher octane, higher
ethanol content test fuel if they could demonstrate that such a fuel
would be used by the operator and would be readily available
nationwide, vehicles would not operate appropriately on other available
fuels, and such a fuel would result in equivalent emissions
performance. For vehicles certified on high-octane, high-ethanol
gasoline, all EPA confirmatory and in-use testing would also be
conducted on high-octane, high-ethanol gasoline. This could help
manufacturers who wish to raise compression ratios to improve vehicle
efficiency as a step toward complying with the 2017 and later light-
duty greenhouse gas and CAFE standards. This in turn could help provide
a market incentive to increase ethanol use beyond E10 and enhance the
environmental performance of ethanol as a transportation fuel by using
it to enable more fuel efficient engines. We seek comment on the
appropriateness of the alternative test fuel provisions at Sec.
1065.701(c) and the need to specify more precisely the makeup of such a
fuel (ethanol content, as well as other fuel parameters) in the
regulations at this time. We are also seeking comment on whether there
are other aspects of today's proposed standards that might need to be
modified to provide an incentive for, or remove obstacles to, the
development of highly efficient vehicles optimized for use on higher
level ethanol blends.
2. Proposed Flexible Fuel Vehicle Test Fuel
    While the Agency has for some time had testing requirements for
flexible fuel vehicles (FFVs) on E85 fuel blends, EPA currently has no
regulatory specifications for the test fuel itself. Historically, our
laboratory practice has been to blend indolene (E0) with neat ethanol
and normal butane to produce an FFV test fuel with 83 volume percent
ethanol and an RVP from 6.0 to 6.5 psi. However, the lack of E85 test
fuel specifications has caused confusion and inconsistency among FFV
manufacturers in carrying out their certification requirements.
    Similar to the previous discussion regarding gasoline test fuels,
we believe it is important that the fuel used to test FFVs reflect the
composition of actual in-use E85. This may become increasingly
important if E85 usage in FFVs increases to help satisfy the growing
RFS2 renewable fuel requirements.
    The term ``E85'' has historically been used to describe an ethanol
blend with a maximum ethanol content of 83 volume percent and specified
minimum ethanol content for use in FFVs. In the recently updated ASTM
International specification, the minimum ethanol concentration was
reduced from 68 to 51 volume percent.\325\ As part of the updated
specification, ASTM retired the name E85 because it has caused

confusion regarding the necessary variability in the ethanol content of
the blend depending upon seasonal climactic conditions. The official
name in the new ASTM specification is ``ethanol fuel blends for
flexible-fuel automotive spark-ignition engines.'' For the sake of
brevity, we shall refer to this fuel as E51-83.
---------------------------------------------------------------------------

    \325\ ASTM International D5798-11, ``Standard Specification for
Ethanol Fuel Blends for Flexible-Fuel Automotive Spark-Ignition
Engines''.
---------------------------------------------------------------------------

    Consistent with our current policy regarding the formulation of FFV
test fuel, we believe that the ethanol content should be at or near the
maximum ethanol level on which the vehicles were designed to operate to
ensure that the testing reflects the full range of in-use formulations
and emissions performance. To provide adequate flexibility for test
fuel manufacturers, we are proposing that the ethanol content must be
from 80 to 83 volume percent. Rather than specify ranges for the other
fuel parameters as we have done for gasoline test fuel in Table IV-21,
we are proposing that the FFV test fuel would be defined based on the
results from blending the proposed E15 standard gasoline test fuel with
ethanol. We propose that denatured fuel ethanol (DFE) that meets the
proposed specifications would be used to increase the ethanol content
to 80 to 83 volume percent.\326\
---------------------------------------------------------------------------

    \326\ The proposed requirements for DFE are contained in Section
V.C of today's preamble.
---------------------------------------------------------------------------

    It is important to ensure that the volatility of FFV test fuel
meets minimum volatility specifications to provide adequate
startability and for safety reasons. The ASTM minimum RVP specification
that conforms to the specified temperature at which FFV emission
testing takes place (68 to 86[emsp14][deg]F) is 5.5 psi. EPA conducted
discussions with vehicle and test fuel manufacturers to arrive at the
current guidance that the RVP of the finished test fuel should be
between 6.0 and 6.5 psi. We propose to formalize the current guidance
in the regulatory requirements for FFV test fuel. We propose that
commercial grade normal butane could be added to trim the RVP of the
finished test fuel to meet the proposed specifications.\327\ A 6.0 to
6.5 range in RVP has historically provided test fuel manufacturers
adequate flexibility in formulating test fuels. Limiting the amount of
butane that is added to formulate FFV test fuels is important because
if excessive volumes of butane were used it could inappropriately
reduce the stringency of emissions testing.
---------------------------------------------------------------------------

    \327\ The specifications for commercial grade butane are
contained in 40 CFR 80.82.
---------------------------------------------------------------------------

    As an alternative to the use of DFE to manufacture FFV test fuel,
we propose that neat (undenatured) fuel grade ethanol could be used. We
also propose that as an alternative to using a finished E15 standard
gasoline test fuel in the manufacture of FFV test fuel that the
gasoline blendstock used to produce a compliant E15 test fuel could be
used to manufacture the FFV test fuel. This would allow ethanol to be
blended only once to produce FFV test fuel. The test fuel manufacturer
would be required to test a sample of the subject gasoline blendstock
after the addition of ethanol to produce a finished standard E15
gasoline test fuel and demonstrate that the blend meets all of the
proposed requirements for standard gasoline test fuel described in
Section IV.D.1.
    We propose that the above FFV emissions test fuel specifications
would become applicable on the same schedule as the proposed E15
standard gasoline test fuel specifications become applicable for light-
and heavy-duty gasoline vehicles (described below in Section IV.D.3).
We believe that the proposed requirements would ensure that FFV test
fuel reflects the composition of in-use ethanol fuel blends for
flexible-fuel automotive spark-ignition engines while minimizing the
burden on the industry with respect to test fuel formulation and the
number of test fuel blend components that must be stored.
    Under the Tier 2 program, FFVs utilize a test fuel containing 10
percent ethanol with an RVP of approximately 10 psi for evaporative
emission testing. The proposed E15 certification fuel for non-FFVs is a
9 psi E15 fuel. We seek comment on whether the new E15 evaporative
emissions test fuel for FFVs should continue to have an RVP of 10 psi
to maintain the level of performance established under the Tier 2
program.
3. Proposed Implementation Schedule
    As described earlier in Section IV.C, we are proposing Tier 3
exhaust and evaporative emission standards with today's notice. The
proposed changes in the specifications for test fuel would apply to
vehicles certified to these new standards. We are proposing to
transition to the new test fuel during the first few years that the
Tier 3 standards are phasing in. As described in Sections IV.A and
IV.B, testing with the new fuel would start with light-duty vehicles
certified to Tier 3 bin standards at or below Bin 70, and heavy-duty
vehicles certified to Tier 3 bin standards at or below Bin 250 (for
Class 2b) and Bin 300 (for Class 3). Starting with model years 2020 for
light-duty and 2022 for heavy-duty, we would require that all
manufacturers use the new test fuel for all exhaust emission testing
(with the exception of Small Volume Manufacturers and small businesses,
which could delay using the new test fuel until model year 2022).
Manufacturers would also need to comply with cold temperature CO and
NMHC standards using the new test fuel for any models that use E15 test
fuel for meeting the light-duty Tier 3 exhaust emission standards.
These same tests would also provide the basis for meeting GHG
requirements under 40 CFR part 86 and fuel economy requirements under
40 CFR part 600, as described in the following section.
    We are proposing to require evaporative emission testing with the
new test fuel for any models that are certified to the Tier 3
evaporative emission standards. To the extent that these models are
different than those used for exhaust emission testing with the new
test fuel, manufacturers would need to do additional testing to
demonstrate compliance with all applicable standards. They may
alternatively use the new test fuel earlier than the regulations
specify to avoid additional testing. We further propose to require that
manufacturers submit certification data based on the new test fuel to
demonstrate compliance with refueling emission standards for any
vehicles that are certified to the Tier 3 evaporative emission
standards.
4. Potential Implications on CAFE Standards, GHG Standards, and Fuel
Economy Labels
    EPA and the National Highway Traffic Safety Administration (NHTSA)
recently finalized a joint greenhouse gas (GHG) emissions and corporate
average fuel economy (CAFE) standards for MY 2017-2025 light-duty
vehicles, light-duty trucks, and medium-duty passenger vehicles.\328\
These GHG and CAFE standards build upon the National Program that was
first announced by the President in May 2009 and which allows
manufacturers to build a single fleet of light vehicles that can
satisfy all federal and state requirements for GHG emissions and fuel
economy. The first round of standards by EPA and NHTSA under the
National Program cover MY 2012-2016.\329\
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    \328\ 77 FR 62623 (October 15, 2012).
    \329\ 75 FR 25324 (May 7, 2010).
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    The recently finalized MY 2017-2025 GHG and CAFE standards affect
essentially the same vehicle classes over the same timeframe as this
proposal for non-GHG emissions standards and gasoline fuel quality.
Accordingly, EPA believes it is important for the two rulemakings to be
coordinated so that manufacturers can develop future

product development plans with a full understanding of the major
regulatory requirements they would be facing over the MY 2017-2025 time
frame.
    The Agency would like to highlight two important issues of overlap
between these two rulemakings: Test fuel and useful life. As explained
above, today's action proposes to update EPA's test fuel to better
match in-use fuels, with the change in test fuel phased-in from MY
2017-2020 for light-duty exhaust emission compliance. The proposal
involves several changes to the emissions test fuel specifications,
including, notably, a 15 percent by volume ethanol content. The current
emissions test fuel contains zero ethanol. Regarding useful life, we
are proposing a longer useful life for some vehicles, as described in
Section IV.A.7.b, from the current 120,000 miles to 150,000 miles.
a. Test Fuel
    The proposed change in test fuel, if finalized, could have
implications for both the CAFE and GHG emissions compliance programs,
as well as the fuel economy labeling program. EPA is committed to the
principle of ensuring that the proposed change in test fuel would not
affect the stringency of either the CAFE or GHG emissions standards,
and that the labeling calculations would be updated to reflect the
change in test fuel.
    While NHTSA establishes the fuel economy standards for the CAFE
program, EPA is responsible for vehicle testing and calculation of fuel
economy values used by manufacturer for compliance with the CAFE
standards. Under the Energy Policy and Conservation Act (EPCA),
limitations are placed on the test procedures used to measure fuel
economy for passenger cars. For passenger automobiles, EPA has to use
the same procedures used for model year 1975 automobiles, or procedures
that give comparable results.\330\ When EPA has made changes to the FTP
or HFET, we have evaluated whether it is appropriate to provide for an
adjustment to the measured fuel economy results, to comply with the
EPCA requirement for passenger cars that the test procedures produce
results comparable to the 1975 test procedures. These adjustments are
typically referred to as a CAFE or fuel economy test procedure
adjustment or adjustment factor.
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    \330\ 49 U.S.C. 32904(c).
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    Because ethanol has a lower energy content than gasoline, i.e.,
fewer British thermal units (Btus) or joules per gallon,\331\ and fuel
economy is defined in terms of miles per gallon of fuel, it is almost
certain that the same vehicle tested on a test fuel with 15 percent
ethanol content will yield a lower fuel economy value relative to the
value if it were tested on the current test fuel with zero ethanol
content. For CAFE purposes, the existing fuel economy equation for
gasoline that has been in use for many years already contains an
adjustment for the energy content of the test fuel to calculate fuel
economy equivalent to what would have been determined using the 1975
baseline test fuel.\332\ Therefore, it is not clear that any further
action is necessary to account for the proposed change in certification
test fuel. Within this equation, however, is a so-called ``R-factor''
to account for the fact that the change in fuel economy is not directly
proportional to the change in energy content of the test fuel. Although
an R-factor of 0.6 has been used since 1988, manufacturers have
suggested that a higher value may be more appropriate. We discuss this
issue in a memo to the docket.\333\ This is a technical issue with the
fuel economy equation that has been raised in the context of the
proposed certification test fuel change, but technically it is distinct
from the proposed change in test fuel. EPA will continue to investigate
this issue and if necessary address it as part of a future action.
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    \331\ EPA estimates that, on average, E85 fuel contains 25-30
percent less energy per gallon than gasoline with zero ethanol.
    \332\ 40 CFR 600.113-12(h)(1).
    \333\ Butler, A. (February 2013) Analysis of the Effects of
Changing Fuel Properties on the EPA Fuel Economy Equation and R-
Factor. Memorandum to the docket.
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    EPA is also committed to retaining equivalent stringency for GHG
emissions compliance associated with the proposed test fuel change. The
proposed changes in test fuel properties in this rule do not have any
appreciable impact on carbon dioxide grams per mile levels. This is
supported by data from the EPAct study, which show that the change in
the test fuel have both positive and negative impacts that offset each
other and that there is no net impact on carbon dioxide grams per mile
levels. This is discussed in a memo to the docket.\334\ We seek comment
on the impact of this proposal on CO2 emissions. Should
action to adjust the compliance calculation for the light-duty GHG
standards become warranted, we would include such changes as a part of
a future action.
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    \334\ Butler, A. (February 2013) Analysis of the Effects of
Changing Fuel Properties on the EPA Fuel Economy Equation and R-
Factor. Memorandum to the docket.
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    EPA expects that there may be a potential impact on manufacturer's
fuel economy and greenhouse gas testing burden during the Tier 3 phase-
in years. Currently, for example, manufacturers carry over a
considerable amount of previous model year data in support of their
Fuel Economy Labeling and CAFE/Greenhouse Gas programs. We are
proposing that Tier 3 compliant vehicles would be required to test on
E15 test fuel, and thus, manufacturers would normally not be allowed to
carry over previous model year data from vehicles tested on E0 test
fuel. EPA anticipates that such carryover requests could be handled
during the Tier 3 phase-in years with modifications to EPA's current
policy for the use of analytically derived data (see EPA's fuel
economy, CO2, and carbon-related exhaust emissions testing
regulations at 40 CFR 600.006-08(e) and EPA guidance letter CD-12-03
(February 27, 2012) and CCD-04-06, (March 11, 2004 \335\)). EPA
requests comments on whether there is a need for further reductions in
fuel economy/greenhouse gas testing burden beyond that allowed by the
above EPA guidance letters. Any comments supporting the need to reduce
fuel economy/greenhouse gas testing burden (beyond that allowed by
EPA's policy for the use of analytically derived data) should describe
one or more specific methods of reducing such testing burden.
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    \335\ EPA Guidance Letters CD-12-03 (Analytically Derived
CO2 and Carbon-Related Exhaust Emissions (CREE) for
Light-Duty Vehicles) and CCD-04-06 (Updated Analytically Derived
Fuel Economy (ADFE) Policy for 2005 MY and Later), March 11, 2004,
is available through the EPA Transportation and Air Quality Document
Index System at: http://iaspub.epa.gov/otaqpub/.
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    Finally, EPA will need to update the fuel economy labeling
calculations in 40 CFR Part 600 to reflect the proposed E15 test fuel.
The current methodology, which took effect with the 2008 model year,
contains equations that, when applied to test results using current
fuel (zero alcohol), adjust for an average national impact of ethanol
in fuel on fuel economy. These equations would need to be revised such
that the adjustment remains consistent with the actual national use of
ethanol in fuel.
b. Useful Life for GHG Standards
    As stated above, EPA is committed to retaining equivalent
stringency for GHG emissions compliance beginning in MY 2017. In
contrast to the proposed Tier 3 test fuel, for which we are uncertain
as to the effects on GHG emissions, we believe that certifying a
vehicle to a longer useful life for any emission constituent would have
only a

beneficial effect on emissions. To address potential concerns about
changes in the stringency of the GHG standards resulting from a longer
useful life, we are not proposing to require a longer useful life for
GHG emission standards. As this approach may result in additional
testing burden, we are proposing that manufacturers could optionally
certify GHG emissions to a 150,000 mile, 15 year useful life.
5. Consideration of Nonroad, Motorcycle, and Heavy-Duty Engine
Emissions Test Fuel
    As described earlier in Section IV.D.1., we are proposing new
specifications for the gasoline emissions test fuel used for testing
highway vehicles subject to the proposed Tier 3 standards. In
developing today's proposal, EPA also considered proposing the change
in test fuel specifications for other categories of engines, vehicles,
equipment, and fuel system components that use gasoline. This would
include a wide range of applications, including small nonroad engines
used in lawn and garden applications, recreational vehicles such as
ATVs and snowmobiles, recreational marine applications, on-highway
motorcycles, and larger heavy-duty gasoline engines. While engines in
some of these categories employ advanced technologies similar to light-
duty vehicles and trucks, the vast majority of these engines employ
much simpler designs, with many of the engines being carbureted with no
electronic controls. Because of lower level of technology, emissions
from these engines are potentially much more sensitive to changes in
fuel quality.
    EPA is not proposing to apply the new emissions test fuel
specifications to these other categories of engines, vehicles,
equipment, and fuel system components. In discussing the potential
change in test fuel specifications with the large number of businesses
potentially impacted by such a change, many companies supported such a
change. However, a number of manufacturers raised concerns about the
level of ethanol in the new fuel, the cost of recertifying emission
families on the new fuel, the impact on nationwide product offerings,
and the cost impact of complying with the existing standards on the new
test fuel. EPA believes it is important that the emissions test fuel
for these other categories reflect real-world fuel qualities but has
elected to defer moving forward now pending additional analysis of the
impacts of changing the test fuel specifications for the wide range of
engines, vehicles, equipment and fuel system components that could be
impacted. These impacts include the impact on the emissions standards,
as well as the other issues raised by the manufacturers. EPA plans to
explore such a change in a separate future action. EPA requests comment
on the implications of changing the test fuel for these other
categories and whether a different test fuel would be more appropriate
for these other categories.
6. Consideration of CNG and LPG Emissions Test Fuel
    There are currently no sulfur specifications for the test fuel used
for certifying natural gas vehicles. There is also no sulfur
specification in Sec.  86.113 for the test fuel used for certifying
liquefied petroleum gas (LPG) vehicles. The corresponding LPG test fuel
for heavy-duty highway engines and for nonroad engines in Sec.
1065.720 includes an 80 ppm maximum sulfur specification.
    We request comment on the appropriateness of changing Sec.  86.113
to reference 40 CFR part 1065 for both natural gas and LPG test fuels.
We further request comment on amending these specifications to better
reflect in-use fuel characteristics, and in particular on the
appropriateness of aligning the sulfur specifications with those that
apply for gasoline test fuel. Changing the sulfur specifications would
depend on establishing that the new specification is consistent with
the range of properties expected from in-use fuels.

E. Small-Business Provisions

    As in previous vehicle rulemakings, our justification for including
provisions specific to small businesses is that these entities
generally have a greater degree of difficulty in complying with the
standards compared to other entities.
    In developing the proposed Tier 3 vehicle program, we evaluated the
environmental need as well as the technical and financial ability of
manufacturers and others to meet the standards as expeditiously as
possible. We believe it is feasible and necessary for the vast majority
of the program to be implemented in the established time frame to
achieve the air quality benefits as soon as possible. Based on
information available from small manufacturers and others, we believe
that entities classified as small generally face unique circumstances
with regard to compliance with environmental programs, compared to
larger entities. Thus, as discussed below, we are proposing several
flexibility provisions for small businesses in the vehicle industry to
reduce the burden that this program could have on them. These proposed
provisions are based on the recommendations of the Small Business
Advocacy Review (SBAR) Panel described in Section XIII.C of today's
proposal and include a few additional provisions.
    Small entities generally lack the resources that are available to
larger companies to carry out necessary research and development and to
raise capital for investing in a new regulatory program. Small entities
are also likely to have more difficulty in competing for any needed
engineering and construction resources and lower production volume over
which to spread their compliance costs. Small entities also tend to
have limited product lines, which limits their ability to take
advantage of the phase-in and ABT flexibility provisions in the
proposal. As such, we are proposing regulatory flexibility provisions
that would provide additional lead time and reduced testing burden for