Control of Air Pollution From New and In-Use Motor Vehicles and
New and In-Use Motor Vehicle Engines; Technical Amendments to the Test
Procedures for Methanol-Fueled Motor Vehicles and Motor Vehicle Engines
and Petroleum-Fueled Motor Vehicles; Final Rule
[Federal Register: June 30, 1995 (Volume 60, Number 126)]
[Rules and Regulations]
[Page 34325-34377]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
ENVIRONMENTAL PROTECTION AGENCY
40 CFR Parts 9, 85, 86, 88 and 600
[AMS-FRL-5203-6]
Control of Air Pollution From New and In-Use Motor Vehicles and
New and In-Use Motor Vehicle Engines; Technical Amendments to the Test
Procedures for Methanol-Fueled Motor Vehicles and Motor Vehicle Engines
and Petroleum-Fueled Motor Vehicles; Final Rule
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
SUMMARY: This rule changes the test procedures previously promulgated
for methanol-fueled vehicles (April 11, 1989). These revisions make
minor corrections to the procedures, provide additional options, and
clarify the Agency's regulatory intent. The changes are expected to
allow manufacturers more flexibility in complying with the applicable
regulations, without sacrificing accuracy of test results. This action
is a part of an ongoing cooperative interaction between Agency staff
and the affected automobile and engine manufacturers to develop the
most efficient test procedures possible for alternative fuels such as
methanol. Among the most significant changes are revisions to the
testing requirements for flexible fuel vehicles (FFVs), the allowance
of electronic mass flow controllers for methanol and formaldehyde
sample systems, the allowance of lower temperatures for some heated
components, establishment of wider tolerances for SHED and CVS
(Constant Volume Sampler) verifications, and specification of the fuel
to be used with all flame ionization detectors. It should be noted that
the revision related to flame ionization detectors affects all lightduty
vehicles, including gasoline-fueled vehicles.
In compliance with the Paperwork Reduction Act, this rule also
displays the Office of Management and Budget (OMB) control numbers
issued under the Paperwork Reduction Act (PRA) for the final rules
titled ``Emission Standards for Clean-fuel Vehicles and Engines,
Requirements for Clean-Fuel Vehicle Conversions, and California Pilot
Test Program'' and the ``Standards for Emissions from Natural GasFueled,
and Liquified Petroleum Gas-Fueled Motor Vehicles and Motor
Vehicle Engines, and Certification Procedures for Aftermarket
Conversions''. Also included in this Final Rule are minor changes that
were proposed in the ``Gaseous-Fueled Vehicles'' and ``Clean Fuel
Fleets'' Notices of Proposed Rulemaking, but were not finalized in the
respective Final Rules.
EFFECTIVE DATE: This final rule is effective July 31, 1995, except the
amendments to part 9 are effective June 30, 1995.
Sections 85.503, 85.505, 86.094-23, 86.094-24, 86.095-35 86.098-28,
86.113-94, 86.142-90, 86.150-98, 86.513-94, 86.542-90, 86.1242-90,
86.1344-94 published at 59 FR 48472 and Sec. 600.113-93 published at 59
FR 39638 and 48472, containing information collection requirements
which have now been approved by OMB, are effective June 30, 1995.
Sections 88.104 (b) and (d), 88.201-94 through 88.206-94, and
88.306-94(b) (1),(2), and (4) published at 59 FR 50042, containing
information collection requirements which have been now approved by
OMB, are effective June 30, 1995.
ADDRESSES: Material relevant to this rulemaking is contained in the
Docket A-92-02. The docket is located at the Air Docket Section (LE-
131), U.S. Environmental Protection Agency, Room M-1500, 401 M Street
SW., Washington, DC 20460, and may be inspected between 8 a.m. and 3
p.m. Monday through Friday. Information may also be obtained from the
U.S. Environmental Protection Agency, Office of Mobile Sources,
Regulation Development and Support Division, Engine and Vehicle
Regulation Branch, 2565 Plymouth Road, Ann Arbor, MI 48105.
FOR FURTHER INFORMATION CONTACT: Charles Moulis, Regulation Development
and Support Division, U.S. Environmental Protection Agency, 2565
Plymouth Road, Ann Arbor, MI 48105. Telephone: (313) 741-7826
SUPPLEMENTARY INFORMATION:
Introduction
On April 11, 1989, EPA published final regulations which extended
the Federal Motor Vehicle Control Program to methanol-fueled vehicles
(54 FR 14427). Where possible, the regulations simply applied the
existing petroleum-fueled vehicle test procedures to methanol-fueled
vehicles. In some cases where that was not possible, it was necessary
to incorporate procedures that were more complicated than the
procedures used to test petroleum-fueled vehicles. Since that time,
several methanol-fueled vehicles have been certified. Overall, the
methanol-fueled vehicle test procedures have proven to be accurate and
reliable, though some minor issues have been raised.
On March 1, 1993, EPA published a Notice of Proposed Rulemaking
(NPRM) proposing several revisions to the test procedures that were
established for methanol-fueled vehicles in 1989 (58 FR 11816). This
rulemaking was initiated to address the minor issues which arose while
implementing the previously promulgated certification procedures for
methanol-fueled vehicles. Some of the issues require only a
clarification of the Agency's regulatory intent, while others require
changes to the test procedures specified in the CFR. The revisions
being promulgated today are essentially the same revisions that were
proposed, though some of proposed revisions are not being finalized.
Also, some of the revisions were modified slightly in response to
public comments on the proposal.
The test procedure changes being finalized today include both
changes to the existing procedures and allowances for different
procedures to be used in place of some of those procedures previously
required. The substantive changes are described below. However, the
reader is advised to read the actual regulatory language, which is also
printed here, for the complete changes.
Also included in this action are minor changes that were proposed
in the ``Gaseous-Fueled Vehicles'' (57 FR 52912, November 5, 1992) and
``Clean Fuel Fleets'' (58 FR 32474, June 10, 1993) Notices of Proposed
Rulemaking, but were omitted from the regulations of the respective
Final Rules. For details, see ``Issues'' 12 and 16
The following discussion is organized by issue. For each issue,
there are separate sections describing what was proposed, the public
comments and EPA's response to them, and a summary of the changes that
are actually being finalized by today's action.
Issues: Proposal, Public Comments, and Final Action
Test Fuels
Proposal
Manufacturers of methanol-fueled flexible fuel vehicles (FFVs) have
been required to comply with the methanol-fueled vehicle standards when
using any fuel mixture within the vehicle's design range. (FFVs are
vehicles that are designed to operate using a methanol fuel, gasoline
and all mixtures of the two). In order to ensure that such vehicles
meet the standards over the full range of fuel mixtures, the previous
regulations (e.g., 40 CFR 86.113) required that manufacturers submit
test data for worst case fuel mixtures. However, it became apparent
that implementation of such an approach is
[[Page 34327]]
problematic, because the worst case fuel mixture may vary for the
various pollutants. Therefore, rather than attempting to identify a
single worst case fuel, the Agency proposed that manufacturers
demonstrate compliance by submitting test data for three fuel mixtures
during certification. The three proposed mixtures were: the methanol
fuel expected to be found in use, gasoline, and the highest volatility
mixture. The use of straight methanol fuel (e.g., M85 <SUP>1) and
straight gasoline would demonstrate compliance at the two extremes of
operation. The high volatility mixture would ensure proper evaporative
emissions controls. This mixture was proposed to be approximately M10.
The Agency indicated that it would retain the right to perform its
confirmatory testing using any mixtures within the design range and to
continue to require compliance with the standards over the full range
as well.
\1\ Methanol fuels are commonly identified by their methanol
content using the abbreviation MXX, where XX is the volumetric
percent of the fuel which is methanol. M85, which is currently the
most common methanol fuel for light-duty vehicles, contains 85
percent methanol and 15 percent gasoline.
For mileage accumulation of FFVs, the previous regulations also
required the use of the worst case fuel mixtures. For reasons similar
to those discussed above, the Agency proposed to allow manufacturers to
alternate between the methanol fuel (e.g., M85) and gasoline, at
mileage intervals not to exceed 5000 miles. The Agency also proposed
requiring that the total volume of the methanol fuel used for mileage
accumulation be at least 25 percent, but not more than 75 percent of
the total fuel volume used.
The original regulations specified that methanol test fuels be
representative of in-use fuels, did not include detailed specifications
of test fuel composition, as has been done for gasoline. This issue was
discussed in the NPRM, but no revisions to this requirement were
proposed.
Public Comments
The American Automobile Manufacturers Association (AAMA)
recommended that EPA not require manufacturers to use all three fuels
(gasoline, M10, and M85) to demonstrate compliance for each engine
family, when the manufacturers certify many methanol-fueled engine
families. They argued that the testing burden associated with using
three fuels for a large number of engine families would be too great.
Instead, AAMA recommended that EPA allow the manufacturers to certify
most methanol-fueled engine families using only M85, as long as they
tested one or two engine families using all three fuels. While the
Agency recognizes that the testing burden using three fuels can be
significantly more than using one fuel (as is the case with gasoline),
the Agency does not believe the AAMA recommendation is sufficient to
demonstrate compliance over the entire range of fuel mixtures for all
engine families. Compliance using M85 does not ensure compliance using
either gasoline, or M10; and compliance of one FFV engine family using
gasoline and M10 does not ensure compliance for all other FFV engine
families.
AAMA also disagreed with EPA's proposal to not adopt a permanent
and well defined methanol certification fuel specification. They stated
that ``it would become difficult, if not impossible, to demonstrate
compliance with all fuels if the fuel properties are allowed to drift
at random.'' The Agency, however, feels strongly that certification
fuel must be representative of in-use fuels. EPA recognizes that test
reproducibility is very important, and thus does not wish to have test
fuel properties varying randomly. The Agency will issue guidance as to
the fuel property specifications which define the representative
methanol fuel(s). The specifications will only change to the extent
that the fuel market as a whole changes, and EPA does not expect that
changes in the specifications will be significant from one year to the
next.
A related point that is worth clarifying pertains to the
possibility of EPA regulating in-use methanol fuels. While the Agency
recognizes that fuel properties such as chloride content (which effects
the corrosivity of the fuel), sulfur content (which can effect catalyst
efficiency), or vapor pressure (which can effect cold-starting) could
impact emissions, it has stated previously that it currently has no
plans to regulate commercial methanol fuels. This position has been
misinterpreted to mean that EPA has already decided that it will not
regulate commercial methanol fuels at any time in the future. However,
it is actually probable that EPA would regulate commercial methanol
fuels if it became apparent that in-use methanol fuel quality was
adversely affecting the environment. The Agency has no current plans to
regulate commercial methanol fuels because it is optimistic that
methanol fuel suppliers will voluntarily adopt industry-wide standards
that will make EPA regulation unnecessary.
Final Action
The Agency will still require that FFVs comply with the standards
when operating on any fuel mixture within the design range, but the
means by which this compliance is demonstrated is being changed. Rather
than attempting to identify a single worst case fuel, manufacturers
will now be required to demonstrate compliance by submitting test data
for three fuel mixtures during certification. These three mixtures are:
the methanol fuel expected to be found in use, gasoline, and the
highest volatility mixture. The highest volatility mixture will be M10
(more specifically, it will contain between nine and thirteen percent
methanol).
While the Agency will accept testing on the above fuels as an
adequate demonstration for certification, it should be emphasized that
the Agency will retain the right to perform its confirmatory testing
using any mixtures within the design range and will require compliance
with the standards over the full range as well.
For mileage accumulation of FFVs, EPA will require manufacturers to
alternate between the methanol fuel (e.g., M85) and gasoline, at
mileage intervals not to exceed 5000 miles. There is an additional
requirement that the total volume of the methanol fuel (e.g., M85) used
for mileage accumulation be at least 25 percent, but not more than 75
percent of the total fuel volume used. The Agency believes that these
requirements will be sufficient to demonstrate the durability of FFVs
in use, where the vehicles may be operated on only methanol, only
gasoline, or alternately on both fuels. EPA is not dictating which test
fuel mixtures should be used for the emissions tests performed to
determine deteriorations factors, but the Agency is currently
recommending that deterioration factors be determined for both the
alcohol fuel and the gasoline fuel.
Implicit in the rationale for the approach discussed above is the
assumption that there would be a reasonable possibility that a
significant number of in-use FFVs would be operated using both M85 and
gasoline. This assumption, however, would not necessarily be valid for
FFV models which had a very significant drop in performance when fueled
with gasoline. If the drop in performance were so drastic that the
vehicle became only marginally functional, then it would be very
unlikely that the vehicle operator would fuel the vehicle with gasoline
unless it were an emergency situation,
[[Page 34328]]
where the fuel tank was empty and no methanol fuel was available. Such
a vehicle is said to have only ``limp home'' capability when operated
with gasoline. The Agency recognizes that it would be reasonable for
these vehicles to be considered dedicated methanol-fueled vehicles for
the purposes of certification, and thus to be certified using only
methanol fuel (M85) for emissions testing and mileage accumulation. The
regulations have been modified to make this clear. Manufacturers should
obtain written approval to classify such vehicles as dedicated vehicles
from the Administrator prior to the start of testing. In determining
how to classify such vehicles, the Administrator would consider the
significance of the drop in performance using gasoline, the expected
availability of methanol fuel, and the expected vehicle use (i.e,
personal, taxi fleets, delivery vehicles, etc.). For example, a
methanol-fueled vehicle which lost 80 percent of its normal power when
using gasoline could be considered a dedicated vehicle; although, if
the vehicle was designed to be significantly overpowered, and still had
adequate acceleration with only 20 percent of its normal power, it
would not be considered a dedicated vehicle.
The regulations still do not specify methanol test fuels more
precisely than to require that the methanol test fuels be
representative of in-use fuels. The broad nature of this requirement is
the result of EPA's previous experience with gasoline. Because in-use
gasolines changed so significantly from the fuel used in certification,
especially in the area of vapor pressure, it became necessary for the
Agency to promulgate extensive regulations for in-use gasoline. The
Agency hopes that regulation of in-use methanol fuel quality will not
be necessary, and that industry-wide methanol fuel standards will be
adopted on a voluntary basis. Such standards would be accepted by EPA
as appropriate certification fuel standards, assuming that in-use fuels
consistently complied with the standards, since it would ensure that
the certification fuel is representative of in-use fuels. EPA
recognizes that, since the current market for methanol fuels is not
well defined, it is not possible at this time to determine one methanol
fuel that is truly representative of in-use fuels in all respects. For
previous certification of methanol-fueled vehicles, the Agency decided
that mixtures of chemical grade methanol and certification gasoline
were sufficiently representative to ensure that certification emissions
results would accurately reflect the behavior of in-use methanol-fueled
vehicles using market fuels. This approach is consistent with the
California Air Resources Board certification fuel specifications,
except that California's specification <SUP>2 does not require that the
methanol be chemical grade, and that it requires the use of
California's certification gasoline. Therefore, until such time that
the methanol fuel market is large enough to allow a better
determination of a representative fuel or until industry-wide standards
are adopted by fuel suppliers, the Agency will use, and require
manufacturers to use either a combination of chemical grade methanol
and certification gasoline in proportions that reflect the composition
of the intended in-use fuel, or California's certification methanol
fuel. For current M85-fueled vehicles this will be 84-88 percent (by
volume) methanol and the remainder gasoline. For M100-fueled vehicles,
the fuel will be neat chemical grade methanol, although it may contain
small amounts of fuel additives, provided that the manufacturer can
demonstrate that those same additives will be included in the in-use
fuel.
\2\ California Code of Regulations, Title 13, Section 2292.
2. Methanol and Formaldehyde Sampling and Analysis
Proposal
The original regulations for methanol-fueled vehicles specified
separate sampling systems for methanol and formaldehyde. In the NPRM
for this action, the Agency proposed revisions in several areas related
to these requirements, although the most basic aspects of the
requirements remain unchanged. Under the proposed regulations, the
samples would still be collected by bubbling the sample gas through two
impingers, or, in the case of formaldehyde, through a cartridge
impregnated with dinitrophenylhydrazine (DNPH); and the impinger fluid
or cartridge would still be analyzed for methanol or formaldehyde using
chromatographic methods.
The most significant of the proposed changes affected the required
sampling flow rates. The previous regulations included minimum
requirements for flow rates through impingers and cartridges. They were
included to ensure that sufficient amounts of methanol and formaldehyde
are collected to allow for accurate detection by the chromatographic
instruments. Because there can be significant variations from system to
system, however, a single minimum flow rate is not appropriate for all
systems. To correct this, the Agency proposed to eliminate these
minimum flow rates, and to instead establish minimum concentrations for
the primary impingers and cartridges. More specifically, EPA proposed
that systems (and procedures) be required to be designed such that
testing of a vehicle or engine that emitted the maximum allowable level
of methanol, or emitted formaldehyde at a level that was ten percent of
the maximum emission level of methanol would result in analyte
concentrations that were 25 times higher than the levels of detection
for the instruments used. Systems that did not meet this requirement
due to high limits of detection were to be allowed, provided that the
resultant methanol concentration was greater than 25 mg/l, and the
resultant formaldehyde concentration is greater than 2.5 mg/l. For any
vehicles or engines that have an applicable formaldehyde standard, the
analyte concentrations used for design would be those that would result
from the maximum emission level allowed by that standard. The Agency
also proposed to add an additional design requirement that the amount
of methanol collected in the secondary impinger not be more than ten
percent of the total amount collected.
Another set of proposed revisions dealt with the method of flow
measurement. In several parts of the previous regulations, dry gas
meters were specifically required for sampling and calibration systems.
This was because dry gas meters were considered to be the most
appropriate type of flow meter for these applications at the time the
test procedures for methanol-fueled vehicles were originally developed.
It has became apparent, however, that these specifications were no
longer necessary. Therefore, the Agency proposed to allow other types
of flow meters to be used, provided that they meet an accuracy
specification of <plus-minus>2 percent.
Public Comments
The comments received regarding methanol and formaldehyde sampling
and analysis were generally supportive of the Agency's proposals. Some
of the comments, however, requested clarification of regulatory
language. In response, EPA has modified the regulatory language
regarding the design requirements for sample flow rates, the use of
secondary impingers and cartridges, and the accuracy specifications for
sample flow meters.
[[Page 34329]]
Final Action
Sampling systems (and procedures) will be required to be designed
such that testing of a vehicle or engine that emitted the maximum
allowable level of methanol (e.g., 0.95 g/mi methanol, or 14 g/FTP, for
a 0.41 g/mi THCE <SUP>3 standard), or emitted formaldehyde at a level
that was twenty percent of the maximum emission level of the lowest
applicable THCE or NMHCE (e.g., 0.082 g/mi formaldehyde, or 1.2 g/FTP,
for a 0.41 THCE standard) during the first phase of the test would
result in analyte concentrations that were at least 25 times higher
than the levels of detection for the instruments used. As proposed,
systems that do not meet this requirement due to high limits of
detection will be allowed, provided that the resultant methanol
concentration is greater than 25 mg/l, and the resultant formaldehyde
concentration is greater than 2.5 mg/l. For any vehicles or engines
that have an applicable formaldehyde standard, the analyte
concentrations used for design would be those that would result from
the maximum emission level allowed by that standard. The Agency is also
requiring that the amount of methanol collected in the secondary
impinger not be more than ten percent of the total amount collected.
\3\ THCE and NMHCE are replacing OMHCE and OMNMHCE; see
discussion in ``15. Other Issues.''
Also, the Agency will allow other types of flow meters to be used,
provided that they meet the accuracy specifications of Secs. 86.120-90
or 86.1320-90. The specifications of these sections require accuracy of
<plus-minus>1 percent of the maximum operating range and <plus-minus>2
percent of the reading.
3. Proportional Sampling
Proposal
Prior to this action, there were only two methods allowed by the
regulations for obtaining proportional samples when testing light-duty
vehicles: the Positive Displacement Pump-Constant Volume Sampler (PDPCVS)
method and the Critical Flow Venturi-Constant Volume Sampler (CFVCVS)
method. However, EPA proposed a third option for methanol-fueled
vehicles. This method is based on the current CFV-CVS system, but
allows proportional sampling of methanol and formaldehyde to be
maintained by electronically monitoring the CVS flow rate and
electronically controlling the sample flows. Similar approaches have
been used for some years in heavy-duty diesel testing and in light-duty
research testing. When using this approach, the ratio of sample flow to
CVS flow was to be required to remain within <plus-minus>5 percent of
the set-point ratio.
Public Comments
AAMA supported the Agency's proposals, and added that flow
controllers should vary the sample flow rate inversely with the square
root of the bulk stream temperature. EPA agrees, and has added such
language to the regulations.
Final Action
EPA is finalizing this revision as proposed. The Agency is not
requiring that these electronically-controlled sampling systems also
include separate flow meters to measure total sample volumes, but will
allow them. It should be emphasized that even though this option is
only being specified for methanol and formaldehyde sampling systems,
the Agency would consider allowing similar approaches for other samples
as equivalent procedures. (For example, paragraph (a)(5) of
Sec. 86.109-94 specifically allows the use of sampling procedures other
than those specified in that section, provided that they can be shown
to ``yield equivalent or superior results''.)
4. Prevention of Condensation
Proposal
Exhaust from methanol-fueled vehicles generally has much higher
water vapor content than conventional vehicles, which can lead to water
condensation under certain testing conditions, when the gas comes into
contact with surfaces at temperatures below its dew point. Such
condensation can create very significant problems with respect to
testing accuracy, since both methanol and formaldehyde are soluble in
water. However, if the gas comes into contact with very hot surfaces,
the methanol can undergo decomposition reactions. For these reasons, in
the previous rulemaking, EPA required that sample lines and transfer
systems be heated to 235<plus-minus>15 deg.F (as measured at the
surface in contact with the raw and diluted exhaust gases). Some
manufacturers, however, have indicated a concern that this temperature
requirement may be too high for their systems. The Agency proposed to
change its regulatory focus from specifying the temperature
requirement, toward allowing manufacturers to determine the most
appropriate temperatures for their own individual systems. The
requirements to heat many of the components remained, but EPA proposed
changing the lower limit to the maximum dew point of the exhaust
mixture. Comments were requested on whether it will be necessary to
measure dew point continuously for each test.
It had also been suggested that heavy-duty engine manufacturers
should be allowed to use ducts up to 32 feet in length to transfer the
exhaust from the engine to the dilution tunnel. Testing by Southwest
Research Institute (SwRI) showed no significant difference between the
emission results from test systems using ducts 13 and 32 feet in
length.<SUP>4 Therefore, the Agency proposed to allow transfer ducts up
to 32 feet in length (as is currently allowed for petroleum-fueled
engines). However, since the SwRI testing did not provide data for
systems in which the duct temperature exceeded 315 deg.C, this
allowance required that the maximum duct temperature not exceed 315
deg.C.
\4\ ``Effect of Exhaust Pipe Length on Emissions From a HeavyDuty
Methanol Engine,'' SwRI-4962, May 1992, Docket Item A-92-02-IID
-7.
EPA also proposed allowing heating and dehumidifying the dilution
air, with some restrictions. The proposed restrictions limited the
maximum temperature and affect how the dilution air flow rate is
calculated.
Public Comments
The comments received regarding the prevention of condensation were
generally supportive of the Agency's proposals. AAMA stated that, based
on their testing experience, measurement of the dew point is not
necessary, provided that dilution systems are designed properly. EPA
agrees that continuous measurement of the dew point is not necessary,
and thus will also allow the absence of condensation to be demonstrated
through engineering analyses.
Detroit Diesel Corporation (DDC) supported EPA's proposal to allow
longer unheated exhaust transfer ducts for heavy-duty engines, but
requested that the Agency raise the maximum temperature from 315 deg.C
(as proposed) to 350 deg.C. Further, they indicated that they believed
that a limit on the average temperature of the duct would be more
appropriate than a limit on the maximum temperature.
EPA recognizes that the 315 deg.C limit was based on testing of
only one engine, and that other larger engines could easily result in
higher temperatures of the duct. However, the Agency does not consider
it to be unreasonable to expect manufacturers to make the slight
modifications to the duct that would be necessary to prevent the
maximum duct temperature from exceeding 315 deg.C. Simple
modifications such as the
[[Page 34330]]
addition of fins, or the use of cooling fans, should be able to
increase the heat transfer away from the duct sufficiently to allow the
systems to comply with this requirement even when testing larger
engines. The Agency also does not agree that a limit on the average
temperature would be more appropriate. While it is true that
controlling the average temperature would account for the length of
time that the exhaust is exposed to the higher temperatures, it would
allow the exhaust to be exposed to very high temperatures. Therefore,
EPA has decided that a limit on the maximum temperature is appropriate
at this time, especially given the increased complexity of determining
the average temperature of the duct instead of only the maximum
temperature.
Final Action
The Agency has changed its regulatory focus from specifying the
temperature requirement, to allowing manufacturers to determine the
most appropriate temperatures for their own individual systems.
However, EPA is establishing a lower limit of 5 deg.F above the
maximum dew point of the exhaust mixture, instead of the maximum dew
point as was proposed. The previously established maximum upper
temperature of 250 deg.F remains in effect. Although these limits
provide slightly less additional flexibility than was proposed, the
Agency believes that they allow for a sufficiently wide range of
temperatures. This revision is not intended to imply that the Agency no
longer believes that the appropriate temperature range for most systems
is 220-250 deg.F, but rather it is intended only to allow the
manufacturers more flexibility. Manufacturers must demonstrate that
their systems will prevent condensation from occurring, and will be
allowed to do so using engineering analyses, such as dew point data
from testing under some worst case conditions (e.g., with a large
engine during a period of high ambient humidity).
EPA is also revising the regulations to allow heavy-duty engine
manufacturers to use longer unheated ducts to transfer the exhaust from
the engine to the dilution tunnel. The Agency will allow transfer ducts
up to 32 feet in length, but will require that the maximum duct
temperature not exceed 315 deg.C. EPA recommends that steps be taken
to minimize the temperature increase in the transfer duct to reduce the
possibility of the methanol and formaldehyde reacting on the walls of
the transfer duct.
Today's rule also specifically allows heating and dehumidifying the
dilution air, with some minor restrictions. Allowing such pretreatment
of the dilution air may help to eliminate some of the condensation
problems associated with methanol-fueled vehicles, and may allow the
use of lower system temperatures as discussed above. The restrictions
limit the maximum temperature and affect how the dilution air flow rate
is calculated.
5. CVS and SHED Calibration and Retention Tests
Proposal
The regulations promulgated in 1989 required that, in addition to
tests previously required for propane, tests also be perfomed to ensure
that there are no losses of methanol in the CVS or SHED. The
regulations specified injecting a known quantity of methanol or propane
into the CVS or SHED, collecting a sample and comparing the amount
calculated from the measured value to the amount injected. The
regulations required, for methanol, that the measured value be within
two percent of injected value. However, actual testing experience by
both EPA and industry has shown that consistently obtaining results
within two percent can be problematic given the current state of
development of methanol test procedures. Therefore, EPA proposed to
establish wider limits (<plus-minus>6 percent) for methanol recoveries
during the calendar years 1992-1995. For SHED testing, these wider
limits were to apply to both agreement between the amount injected and
the initial measured amounts (recovery tests) and between the initial
and final (after four hours) measured amounts (retention tests). EPA
requested comments regarding whether it was sufficient to widen the
tolerances through 1995, or if a longer period were required.
The Agency also proposed to require the use of a correction factor
that would be derived from the four-hour retention test. This was to be
a means of accounting for potential losses without increasing the
testing burden.
Public Comments
AAMA supported permanently widening the tolerances for CVS and SHED
recovery and retention tests for methanol to <plus-minus>6 percent.
They stated in their comments that they ``do not believe that a 2
percent limit will be achievable in the near future.'' EPA recognizes
that, at this time, complying with a 2 percent tolerance is not
possible without an unreasonable test burden. This is due in large part
to the imprecision of the GC analysis, which AAMA estimated at
<plus-minus>5 percent. This imprecision could be reduced by performing
multiple GC analyses, although this would lead to a significant
increase in costs. When the vehicles are tested for compliance with a
carbon equivalence-based standard, however, the accuracy of the
methanol measurement becomes less important. Since the test procedure
determines the emissions of non-oxygenated HC by subtracting the
methanol FID response from the total FID response, an undermeasurement
of methanol will lead to an overmeasurement of HC, and vice versa. Thus
the net impact of the accuracy of the methanol measurement on the
accuracy of the calculated THCE emission rate is reduced. However, EPA
continues to believe that the 2 percent tolerance will ultimately be
achievable, and that this level of accuracy is appropriate. Therefore,
the Agency will maintain this specification, but will allow
manufacturers to request a waiver from the required 2 percent tolerance
after 1995, as described below.
AAMA opposed the use of correction factors for SHED testing. They
argued that correction factors are not necessary, and would be
``inconsistent with previous test requirements.'' EPA recognizes AAMA's
concerns. More importantly, however, the Agency believes that the
potential for losses can be addressed under the waiver provisions being
established today (see Final Action section below). Therefore, EPA is
not finalizing the proposed correction factor requirements.
Final Action
EPA is establishing a wider tolerance of <plus-minus>6 percent for
methanol recovery and retention during the calendar years 1992-1995, as
was proposed. After 1995, the Agency will allow manufacturers to
request a waiver from the required tolerance (e.g., <plus-minus>2
percent), provided that:
(1) The Administrator determines that compliance with the specified
tolerance is not practically feasible, and
(2) The manufacturer makes information available to the
Administrator which indicates that the calibration tests and their
results are consistent with good laboratory practice, and that the
results are consistent with the results of calibration testing
conducted by the Administrator, and
(3) The manufacturer complies with higher tolerances (up to
<plus-minus>6 percent for recoveries and <plus-minus>8 for retention),
as specified by the Administrator.
In deciding whether to grant the waiver, and what the tolerances
should be under the waiver, EPA will be
[[Page 34331]]
concerned primarily with the degree to which any imprecision and
inaccuracy in the methanol sampling and measurement techniques would
affect its ability to determine compliance with emission standards.
More specifically, this means that the precision (repeatability) of
methanol measurements should be as good as is practically feasible, and
that there should be no losses in the system that would lead to a
significant undermeasurement of methanol. The determination of
practical feasibility will depend on the degree to which variability
can be reduced and the costs associated with the reduction. EPA
recognizes that the standard for precision that is ``consistent with
good laboratory practice'' will change with time, and will use its own
testing as the standard. That means that manufacturers will be required
to have precision that, in the Administrator's judgement, is
essentially as good as that of EPA.
6. Fuels for Flame Ionization Detectors
Proposal
Flame ionization detectors measure hydrocarbons and other organics
by ionizing the carbon atoms with a supplemental fuel source. At one
time, the primary fuel was a mixture of hydrogen in nitrogen (H<INF>2/
N<INF>2), but now the more commonly used fuel is a mixture of hydrogen
in helium (H<INF>2/He), which is thought to give a more accurate
response. In the previous regulations, it was somewhat unclear what
type of fuels were to be used with the heated flame ionization
detectors (heated FID or HFID) required for methanol-fueled vehicle
testing. Evaporative emissions testing and heavy-duty exhaust testing
required the use of H<INF>2/He, while the fuel for light-duty exhaust
testing was previously unspecified. Since the light-duty fuel was
unspecified, many testing facilities have used a mixture of hydrogen in
nitrogen. To eliminate this confusion, the Agency proposed to clearly
require that H<INF>2/He fuel be used for all FIDs when testing
methanol-fueled vehicles. Moreover, to provide consistent testing of
both alternatively-fueled and conventionally-fueled vehicles, the
Agency proposed to require the use of H<INF>2/He fuel for all heated
and unheated FIDs. The Agency also requested comments on whether
revisions are needed to the FID calibration procedure as outlined in
the CFR.
Public Comments
AAMA agreed with EPA's proposal to require that hydrogen/helium
mixtures be used as the fuel for all flame ionization detectors (FIDs).
AAMA also recommended that EPA add a requirement to optimize the FID to
make the response of methane (relative to propane) as close to one as
possible. The Agency agrees that optimizing the FID to reduce
variations in response factors is good engineering practice. However,
EPA has not seen evidence that FIDs are currently being improperly
calibrated, and thus does not believe that it is necessary to include
such a provision in the regulations at this time. EPA will continue to
consider this issue, and may propose further specifications for the
calibration of FIDs at a later time.
Final Action
EPA is finalizing this revision as proposed, and will require the
use of H<INF>2/He fuel for all heated and unheated FIDs.
7. Background Measurements
Proposal
The test procedures call for measurement of background
concentrations of various gases, including methanol and formaldehyde,
to be subtracted from the concentrations measured in the diluted
exhaust. Previously, only a single sample was required for
formaldehyde, while separate phase-by-phase samples were required for
methanol. However, for the purpose of consistency, EPA proposed to also
require only a single sample be collected to determine the methanol
concentration in the dilution air. It was also noted that, since
methanol levels in the dilution air will generally be very low, a
single impinger is sufficient to measure the methanol concentration in
the sample.
Public Comments
The comments received regarding the background measurements were
generally supportive of the Agency's proposals. DDC requested that EPA
clearly state in the regulations that background measurements are
optional for manufacturers. EPA agrees, and has added such language.
Final Action
EPA is finalizing this revision as proposed, and is also adding
regulatory language that states that background measurements are
optional for manufacturers.
8. Determination of Fuel Composition
Proposal
The regulations previously did not specify a procedure to determine
the carbon:hydrogen:oxygen ratio for methanol fuels and fuel mixtures,
other than to state that the ratio was to be measured. However, if the
methanol fuel and/or fuel mixtures are made from fuels for which the
ratios are known (such as chemical grade methanol and Indolene), then
the ratio for the resultant mixture can be calculated and no
measurement is necessary. EPA proposed to revise the regulations to
allow for calculation of the ratio for methanol fuels and fuel
mixtures.
Public Comments
The comments received regarding the determination of fuel
composition were supportive of the Agency's proposals.
Final Action
EPA is finalizing this revision as proposed.
9. NOXHumidity Correction Factor
Proposal
The humidity of the air in a test area is known to have an effect
on emissions of NO<INF>X, and EPA has established a correction factor
for NOXtest results. It became apparent that the correction
factor established for heavy-duty methanol-fueled engines is erroneous.
EPA proposed to correct this by applying the correction factor
currently specified for gasoline-fueled engines to Otto-cycle methanolfueled
engines, and the one currently specified for petroleum-fueled
diesel engines to methanol-fueled diesel engines, as was originally
intended.
Public Comments
EPA received no comments regarding this issue.
Final Action
EPA is finalizing this revision as proposed.
10. Heated Flame Ionization Detectors
Proposal
The regulations previously required that heated FIDs (HFIDs) be
used when testing methanol-fueled vehicles. The reason for this
requirement was that HFIDs provide a stable response for methanol more
quickly than unheated FIDs. Some manufacturers have suggested, however,
that in many cases the HFID is not necessary and that an unheated FID
is adequate. EPA proposed to allow unheated FIDs to be used in place of
heated FIDs for methanol-fueled vehicle testing.
Public Comments
The Agency received mixed comments in response to this proposed
revision. AAMA supported the use of
[[Page 34332]]
unheated FIDs for methanol-fueled vehicle testing, though they
indicated that they believe that it would be appropriate to require
that each test lab provide data to demonstrate equivalence between
their unheated FID and a heated FID, for their exhaust systems. The New
York State Department of Environmental Conservation (NYDEC) commented
that aromatic organics and large aliphatics can be lost to unheated
surfaces in sampling systems. They recommended that heated FIDs should
be used not only for testing methanol-fueled vehicles, but for testing
petroleum-fueled vehicles as well. Based on these comments, and data
from EPA testing (see Docket A-92-02), it is clear that unheated FIDs
can be used for methanol testing in some systems, but that there is the
potential for measurement problems in other systems. EPA will allow
unheated FIDs to be used in place of heated FIDs for evaporative
testing of methanol-fueled vehicles. The Agency will also allow the use
of unheated FIDs for exhaust testing, where there appears to be a
greater potential for measurement problems, but only after the
manufacturer demonstrates equivalence with the heated FID for its
system. EPA did not propose requiring heated FIDs for gasoline-fueled
vehicle testing and has not yet received sufficient information that it
is necessary.
Final Action
EPA will allow unheated FIDs to be used in place of heated FIDs for
evaporative testing of methanol-fueled vehicle testing. The Agency will
also allow the use of unheated FIDs for exhaust testing, provided that
the manufacturer can demonstrate equivalence with the heated FID for
its system.
11. Gaseous Standards for Methanol and Formaldehyde
Proposal
Gaseous standards of many gases have been specified in the
regulations and have been routinely used in calibration procedures;
however, such standards were not allowed for methanol and formaldehyde.
EPA proposed to allow the use of gaseous methanol standards for
response factor calculation, with the requirement that the
concentration of methanol in the standard gas not vary by more than two
percent over its useful lifetime (i.e., from the time it is prepared
until it is no longer used for testing).
Public Comments
AAMA supported EPA's proposal to allow the use of gaseous methanol
standards for the determination of the FID response to methanol.
However, they suggested that EPA widen the tolerance for stability to
<plus-minus>4 percent (instead of <plus-minus>2 percent) to account for
variability in the measurement of methanol. They also suggested that
EPA allow bottles that exceed this tolerance to be renamed with the new
concentration. The Agency recognizes that the variability associated
with measuring methanol makes it possible that the measured
concentration of methanol could be outside the <plus-minus>2 percent
tolerance, even though the true concentration had not changed by more
than 2 percent. Therefore, EPA has added regulatory language that
clarifies that the <plus-minus>2 percent tolerance is for a reasonable
estimate of the true concentration, taking into account measurement
variability, not necessarily a single measurement. The Agency envisions
that manufacturers will use an average of multiple measurements to
determine the concentration, and will make enough measurements so that
the precision of the estimate is <plus-minus>2 percent. Also, EPA
agrees that standards that change by more than 2 percent can be renamed
with the new concentration, provided that the change is not greater
than 10 percent.
Final Action
EPA will allow the use of gaseous methanol standards for response
factor calculation, with the requirement that the concentration of
methanol in the standard gas shall not vary by more than two percent,
without being relabeled with the new concentration.
12. Idle CO Testing
Proposal
In the 1989 FRM, EPA established idle CO emission standards for all
methanol-fueled light-duty trucks and heavy-duty engines, including
heavy-duty diesel engines. In the NPRM for this current rulemaking, EPA
proposed to modify the testing provisions to allow for continuous
analysis instead of bag sampling and analysis. This was done to be
consistent with Sec. 86.1310, which allows continuous CO analysis for
transient testing of diesel cycle engines.
Public Comments
EPA received no comments regarding this issue.
Final Action
EPA is finalizing this revision as proposed.
In a related matter, EPA is correcting Secs. 86.094-9 and 86.097-9
to clarify that the idle CO standards of those sections are applicable
to gasoline-fueled, methanol-fueled, LPG-fueled and CNG-fueled lightduty
trucks. The applicability of these standards to LPG-fueled and
CNG-fueled light-duty trucks was specified in the Preamble of the FRM
which established standards and test procedures for gaseous-fueled
vehicles ( FR ), but the regulatory text of these sections was not
revised to reflect this requirement.
13. Direct Measurement of Non-Oxygenated Hydrocarbons
Proposal
Evaporative non-oxygenated hydrocarbon emissions from methanolfueled
vehicles have been measured by separately measuring total
organic emissions and methanol emissions: the non-oxygenated
hydrocarbon emissions are the difference between these two
measurements. It had been suggested, however, that non-oxygenated
hydrocarbons can be measured directly by installing water-filled
impingers upstream of an FID calibrated on propane. The impingers would
be expected to remove the methanol from the gas as it is bubbled
through the water, but not the non-oxygenated hydrocarbons. The Agency
proposed to revise the regulations to allow this option.
Public Comments
The comments received indicate that the technique which was
proposed to measure non-oxygenated HC directly for methanol-fueled
vehicles is not sufficiently accurate at this time.
Final Action
EPA is not finalizing this option in this action.
14. FID Measurement of Methanol Emissions From M100 Vehicles
Proposal
Methanol emissions from M100 vehicles have been measured with an
impinger system. The combined emissions of methanol and non-oxygenated
HC have been measured by a FID and the non-oxygenated HC emissions have
been determined by subtracting the methanol (after correcting for FID
response) from the total. However, when the non-oxygenated HC emissions
are small, there is a significant potential for errors. Because the
amount of non-oxygenated HC emissions from M100 vehicles and engines is
generally small, EPA proposed to allow measurement of the
[[Page 34333]]
total emissions with an FID calibrated on methanol, as has already been
allowed through model year 1994.
Public Comments
AAMA supported this option to some extent, but felt that EPA should
not use this option for its testing. At this time, EPA believes that
the available information is not sufficient to support continuation of
this option beyond the 1994 model year.
Final Action
EPA is not finalizing this option in this action.
15. Collection of Methanol Samples
As noted above, methanol samples have been collected using
impingers. EPA also proposed, however, allowing two alternative
methods. The first was the allowance to measure methanol concentrations
from SHED testing by direct GC analysis of the bag samples. The second
alternative was the allowance of the use of cartridges, which are
designed to collect methanol, for both exhaust and evaporative testing.
Public Comments
The comments received regarding the measurement of methanol by GCbag
analysis or from methanol cartridges do not support either of the
proposed approaches at this time.
Final Action
EPA is not finalizing either approach in this action.
16. Other Issues
AAMA indicated that the tolerance of <plus-minus>0.5 percent for
the liquid methanol injection device used during CVS and SHED
calibration may not be achievable at this time. EPA agrees, especially
since manufacturers will still be required to comply with the recovery
and retention tolerances specified by the Administrator. Thus, the
Agency is allowing less precise methods to be used. This change will
not effect the accuracy or precision of certification emissions tests.
AAMA requested that the Agency require the determination of the FID
response to methanol only twice annually, instead of monthly. However,
EPA believes that the response factor should be calculated each time
the FID is recalibrated, on a monthly basis.
EPA is replacing the terms ``Organic Material Hydrocarbon
Equivalent'' (OMHCE) and ``Organic Material Non-Methane Hydrocarbon
Equivalent'' (OMNMHCE) with ``Total Hydrocarbon Equivalent'' (THCE) and
``Non-Methane Hydrocarbon Equivalent'' (NMHCE). These new terms are
simpler and are more obviously related to the comparable terms being
used for petroleum-fueled vehicles (THC and NMHC). This change does not
have any substantive effect on the certification process.
Finally, included among the regulatory revisions in this FRM are
minor changes that allow the test procedures specified for measuring
formaldehyde from methanol-fueled heavy-duty engines to be used to
measure formaldehyde from other types of engines. These changes were
originally proposed in the ``Clean Fueled Fleets'' NPRM (58 FR 32474,
June 10, 1993), but were not finalized. The purpose of the changes is
to provide a means of measuring formaldehyde from non-methanol fueled
heavy-duty ULEV engines that have to comply with a separate
formaldehyde standard. In general, the changes are nothing more than
removing references such as ``for methanol-fueled engines'' that are
associated with the formaldehyde measurement procedures, and replacing
those references with ``as applicable.''
OMB Approval of Information Collection Requirements for CFV Emission
Standards and Gaseous Fuels Rulemakings
EPA is also amending the table of currently approved information
collection request (ICR) control numbers issued by OMB for various
regulations. Today's amendment updates the table to accurately display
those information requirements promulgated under Emission Standards for
Clean-fuel Vehicles and Engines, Requirements for Clean-Fuel Vehicle
Conversions, and California Pilot Test Program which appeared in the
Federal Register on September 30, 1994 (59 FR 50042) and under
Standards for Emissions From Natural Gas-Fueled, and Liquefied
Petroleum Gas-Fueled Motor Vehicles and Motor Vehicle Engines, and
Certification Procedures for Aftermarket Conversions which appeared in
the Federal Register on September 21, 1994 (59 FR 48472). The affected
regulations are codified at 40 CFR Parts 9, 85, 86, 88, and 600. EPA
will continue to present OMB control numbers in a consolidated table
format to be codified in 40 CFR part 9 of the Agency's regulations, and
in each CFR volume containing EPA regulations. The table lists the
section numbers with reporting and recordkeeping requirements, and the
current OMB control numbers. This display of the OMB control numbers
and its subsequent codification in the Code of Federal Regulations
satisfies the requirements of the Paperwork Reduction Act (44 U.S.C.
3501 et seq.) and OMB's implementing regulations at 5 CFR part 1320.
Environmental and Economic Impacts
This regulation is intended only to reduce the administrative and
testing burden of certifying methanol-fueled vehicles. It does not
affect the stringency of emission standards. Thus, it should have no
impact on the environment.
This regulation does provide manufacturers some additional
flexibility, and will result in minor economic benefits. These economic
benefits, however, are expected to be small.
Statutory Authority
The statutory authority for this action is provided by sections
202(a) (1)-(2), 206, 301(a) of the Clean Air Act (42 U.S.C. 7521(a),
7525, and 7601(a)).
Administrative Designation and Regulatory Analysis
Under Executive Order 12866, EPA must judge whether a regulation is
``significant'' and, therefore, subject to OMB review and the
requirements of the Executive Order. This regulation is not a
``significant regulatory action'' because the amendments make only
minor and technical changes.
This Amendment to the final rule is not subject to the Office of
Management and Budget's review under the Executive Order and no
Regulatory Impact Analysis was prepared.
Reporting and Recordkeeping Requirements
The information collection requirements in this rule have been
approved by the Office of Management and Budget (OMB) under the
Paperwork Reduction Act, 44 U.S.C. 3501 et seq and have been assigned
control number 2060-0104. An Information Collection Request document
has been prepared by EPA (ICR No. 783.21) and a copy may be obtained
from Sandy Farmer, Information Policy Branch; EPA; 401 M St., SW.
(2136); Washington, DC 20460 or by calling (202) 260-2740.
Public reporting burden for this collection of information is
estimated to have a negligible effect on the existing clearance which
averages 15,900 hours per response, including time for reviewing
instructions, searching existing data sources, gathering and
maintaining the data needed, and completing the collection of the
information.
Send comments regarding the burden estimate or any other aspect of
this collection of information, including
[[Page 34334]]
suggestions for reducing this burden to Chief, Information Policy
Branch; EPA; 401 M St., SW. (2136); Washington, DC 20460; and to the
Office of Information and Regulatory Affairs, Office of Management and
Budget, Washington, DC 20503, marked ``Attention: Desk Officer for
EPA.''
All the information collection requirements for both the CFV
Emission Standards and Gaseous Fuels Emission Standards rulemakings
have been approved by the Office of Management and Budget under the
Paperwork Reduction Act, 44 U.S.C. 3501 et seq. and have been assigned
either control number 2060-0104 or 2060-0314.
Regulatory Flexibility Act
Under the Regulatory Flexibility Act. 5 U.S.C. 601 et seq., the
Administrator of EPA is required to determine whether a regulation will
have a significant economic impact on a substantial number of small
entities and, if so, to perform a regulatory flexibility analysis. The
technical amendments contained in this rulemaking will not increase the
burden or cost of compliance for any segment of the automotive
industry. Therefore, pursuant to 5 U.S.C. 605(b), I hereby certify that
this rule will not have a significant economic impact on a substantial
number of small entities.
List of Subjects
40 CFR Part 9
Reporting and recordkeeping requirements.
40 CFR Part 86
Environmental protection, Administrative practice and procedure,
Air pollution control, Gasoline, Labeling, Motor vehicles, Motor
vehicle pollution, Reporting and recordkeeping requirements.
Dated: April 28, 1995.
Carol M. Browner,
Administrator.
For the reasons set forth in the preamble, parts 9 and 86 of title
40 of the Code of Federal Regulations are amended as follows:
PART 9--[AMENDED]
The authority citation for part 9 continues to read as follows:
Authority: 7 U.S.C. 135 et seq., 136-136y; 15 U.S.C. 2001, 2003,
2005, 2006, 2601-2671; 21 U.S.C. 331j, 346a, 348; 31 U.S.C. 9701; 33
U.S.C. 1251 et seq., 1311, 1313d, 1314, 1321, 1326, 1330, 1344, 1345
(d) and (e), 1361; E.O. 11735, 38 FR 21243, 3 CFR, 1971-1975 Comp.
p. 973; 42 U.S.C. 241, 242b, 243, 246, 300f, 300g, 300g-1, 300g-2,
300g-3, 300g-4, 300g-5, 300g-6, 300j-1, 300j-2, 300j-3, 300j-4,
300j-9, 1857 et seq., 6901-6992k, 7401-7671q, 7542, 9601-9657,
11023, 11048.
1a. Section 9.1 is amended in the table by adding in numerical
order new entries under the center headings ``Control of Air Pollution
>From Motor Vehicles and Motor Vehicle Engines,'' ``Control of Air
Pollution from New and In-Use Motor Vehicles and New and In-Use Motor
Vehicle Engines: Certification and Test Procedures,'' ``Clean-Fuel
Vehicles'' and ``Fuel Economy of Motor Vehicles,'' to read as follows:
Sec. 9.1 OMB approvals under the Paperwork Reduction Act.
* * * *
OMB control
40 CFR citation No.
Clean-Fuel Vehicles
Fuel Economy of Motor Vehicles