[Code of Federal Regulations]
[Title 40, Volume 17]
[Revised as of July 1, 2004]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR86.090-24]
[Page 119-126]
TITLE 40--PROTECTION OF ENVIRONMENT
CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
PART 86_CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND
ENGINES--Table of Contents
Subpart A_General Provisions for Emission Regulations for 1977 and Later
Sec. 86.090-24 Test vehicles and engines.
(a)(1) The vehicles or engines covered by an application for
certification will be divided into groupings of engines which are
expected to have similar emission characteristics throughout their
useful life. Each group of engines with similar emission characteristics
shall be defined as a separate engine family.
(2) To be classed in the same engine family, engines must be
identical in all the following respects:
[[Page 120]]
(i) The cylinder bore center-to-center dimensions.
(ii)-(iii) [Reserved]
(iv) The cylinder block configuration (air cooled or water cooled;
L-6, 90[deg] V-8, etc.).
(v) The location of the intake and exhaust valves (or ports).
(vi) The method of air aspiration.
(vii) The combustion cycle.
(viii) Catalytic converter characteristics.
(ix) Thermal reactor characteristics.
(x) Type of air inlet cooler (e.g., intercoolers and after-coolers)
for diesel heavy-duty engines.
(3)(i) Engines identical in all the respects listed in paragraph
(a)(2) of this section may be further divided into different engine
families if the Administrator determines that they may be expected to
have different emission characteristics. This determination will be
based upon a consideration of the following features of each engine:
(A) The bore and stroke.
(B) The surface-to-volume ratio of the nominally dimensioned
cylinder at the top dead center positions.
(C) The intake manifold induction port size and configuration.
(D) The exhaust manifold port size and configuration.
(E) The intake and exhaust valve sizes.
(F) The fuel system.
(G) The camshaft timing and ignition or injection timing
characteristics.
(ii) Light-duty trucks and heavy-duty engines produced in different
model years and distinguishable in the respects listed in paragraph
(a)(2) of this section shall be treated as belonging to a single engine
family if the Administrator requires it, after determining that the
engines may be expected to have similar emission deterioration
characteristics.
(4) Where engines are of a type which cannot be divided into engine
families based upon the criteria listed in paragraphs (a)(2) and (a)(3)
of this section, the Administrator will establish families for those
engines based upon those features most related to their emission
characteristics. Engines that are eligible to be included in the same
engine family based on the criteria in paragraphs (a)(2) and (a)(3)(i)
of this section may be further divided into different engine families if
the manufacturer determines that they may be expected to have different
emission characteristics. This determination will be based upon a
consideration of the following features of each engine:
(i) The dimension from the center line of the crankshaft to the
center line of the camshaft.
(ii) The dimension from the center line of the crankshaft to the top
of the cylinder block head face.
(iii) The size of the intake and exhaust valves (or ports).
(5) Gasoline-fueled and methanol-fueled light-duty vehicles and
light-duty trucks covered by an application for certification will be
divided into groupings which are expected to have similar evaporative
emission characteristics throughout their useful life. Each group of
vehicles with similar evaporative emission characteristics shall be
defined as a separate evaporative emission family.
(6) For gasoline-fueled or methanol-fueled light-duty vehicles and
light-duty trucks to be classed in the same evaporative emission family,
vehicles must be similar with respect to:
(i) Type of vapor storage device (e.g., canister, air cleaner,
crankcase).
(ii) Basic canister design.
(iii) Fuel system.
(7) Where vehicles are of a type which cannot be divided into
evaporative emission families based on the criteria listed above, the
Administrator will establish families for those vehicles based upon the
features most related to their evaporative emission characteristics.
(8)(i) If the manufacturer elects to participate in the Alternative
Durability Program, the engine families covered by an application for
certification shall be grouped based upon similar engine design and
emission control system characteristics. Each of these groups shall
constitute a separate engine family group.
(ii) To be classed in the same engine family group, engine families
must contain engines identical in all of the following respects:
(A) The combustion cycle.
[[Page 121]]
(B) The cylinder block configuration (air-cooled or water-cooled; L-
6, V-8, rotary, etc.).
(C) Displacement (engines of different displacement within 50 cubic
inches or 15 percent of the largest displacement and contained within a
multidisplacement engine family will be included in the same engine
family group).
(D) Catalytic converter usage and basic type (noncatalyst, oxidation
catalyst only, three-way catalyst equipped).
(9) Engine families identical in all respects listed in paragraph
(a)(8) of this section may be further divided into different engine
family groups if the Administrator determines that they are expected to
have significantly different exhaust emission control system
deterioration characteristics.
(10) A manufacturer may request the Administrator to include in an
engine family group, engine families in addition to those grouped under
the provisions of paragraph (a)(8) of this section. This request must be
accompanied by information the manufacturer believes supports the
inclusion of these additional engine families.
(11) A manufacturer may combine into a single engine family group
those light-duty vehicle and light-duty truck engine families which
otherwise meet the requirements of paragraphs (a)(8) through (a)(10) of
this section.
(12) The vehicles covered by an application for certification
equipped with gasoline-fueled or methanol-fueled heavy-duty engines will
be divided into groupings of vehicles on the basis of physical features
which are expected to affect evaporative emissions. Each group of
vehicles with similar features shall be defined as a separate
evaporative emission family.
(13) For vehicles equipped with gasoline-fueled or methanol-fueled
heavy-duty engines to be classed in the same evaporative emission
family, vehicles must be identical with respect to:
(i) Method of fuel/air metering (i.e., carburetion versus fuel
injection).
(ii) Carburetor bowl fuel volume, within a 10 cc range.
(14) For vehicles equipped with gasoline-fueled or methanol-fueled
heavy-duty engines to be classed in the same evaporative emission
control system, vehicles must be identical with respect to:
(i) Method of vapor storage.
(ii) Method of carburetor sealing.
(iii) Method of air cleaner sealing.
(iv) Vapor storage working capacity, within a 20 g range.
(v) Number of storage devices.
(vi) Method of purging stored vapors.
(vii) Method of venting the carburetor during both engine off and
engine operation.
(viii) Liquid fuel hose material.
(ix) Vapor storage material.
(15) Where vehicles equipped with gasoline-fueled or methanol-fueled
heavy-duty engines are types which cannot be divided into evaporative
emission family-control system combinations based on the criteria listed
above, the Administrator will establish evaporative emission family-
control system combinations for those vehicles based on features most
related to their evaporative emission characteristics.
(16) No 1990 or later model year heavy-duty engine which is to be
used to generate emission credits for 1991 and later banking, trading
and averaging programs may also utilize nonconformance penalties (NCPs).
Use of an NCP thus becomes an engine family criterion.
(i) Use of either a NOX or a particulate matter NCP by an
engine family precludes that family from generating both NOX
and particulate matter emission credits.
(ii) If a manufacturer desires to use both banked credits and NCPs
on an engine family, two separate engine families must be established.
One engine family must consist of engines certified for only credit use
following the procedure specified in this subpart. The other engine
family must be certified for only NCP use following the procedure as
specified in 40 CFR part 86, subpart L.
(17) Any 1990 or later model year urban bus engines which are to be
used to generate PM credits for the 1991 and later model year urban bus
PM standard shall be placed in separate engine families for
certification purposes and the families shall be clearly designated as
such in the application. Urban bus engines of different basic design
will
[[Page 122]]
not be in the same family. If a manufacturer certifies two or more
different urban bus engines these shall be in different engine families.
(b) Emission data--(1) Emission-data vehicles. Paragraph (b)(1) of
this section applies to light-duty vehicle and light-duty truck
emission-data vehicles.
(i) Vehicles will be chosen to be operated and tested for emission
data based upon engine family groupings. Within each engine family, one
test vehicle will be selected based on the following criteria: The
Administrator shall select the vehicle with the heaviest equivalent test
weight (including options) within the family. Then within that vehicle
the Administrator shall select, in the order listed, the highest road-
load power, largest displacement, the transmission with the highest
numerical final gear ratio (including overdrive), the highest numerical
axle ratio offered in that engine family and the maximum fuel flow
calibration.
(ii) The Administrator shall select one additional test vehicle from
within each engine family. The vehicle selected shall be the vehicle
expected to exhibit the highest emissions of those vehicles remaining in
the engine family. If all vehicles within the engine family are similar
the Administrator may waive the requirements of this paragraph.
(iii) Within an engine family and exhaust emission control system,
the manufacturer may alter any emission-data vehicle (or other vehicles
such as including current or previous model year emission-data vehicles,
fuel economy data vehicles, and development vehicles provided they meet
emission-data vehicles, protocol) to represent more than one selection
under paragraphs (b)(1) (i), (ii), (iv), or (vii) of this section.
(iv) If the vehicles selected in accordance with paragraphs (b)(1)
(i) and (ii) of this section do not represent each engine-system
combination, then one vehicle of each engine-system combination not
represented will be selected by the Administrator. The vehicle selected
shall be the vehicle expected to exhibit the highest emissions of those
vehicles remaining in the engine family.
(v) For high-altitude exhaust emission compliance for each engine
family, the manufacturer shall follow one of the following procedures:
(A) The manufacturer will select for testing under high-altitude
conditions the vehicle expected to exhibit the highest emissions from
the nonexempt vehicles selected in accordance with Sec. 86.090-24(b)(1)
(ii), (iii), and (iv) of this section or,
(B) In lieu of testing vehicles according to paragraph (b)(1)(v)(A)
of this section, a manufacturer may provide a statement in its
application for certification that, based on the manufacturer's
engineering evaluation of such high-altitude emission testing as the
manufacturer deems appropriate,
(1) That all light-duty vehicles not exempt under Sec. 86.090-8(h)
comply with the emission standards at high-altitude, and
(2) That light-duty trucks sold for principal use at designated
high-altitude locations comply with the high-altitude emission
requirements, and that all light-duty trucks sold at low-altitude, which
are not exempt under Sec. 86.090-9(g)(2), are capable of being modified
to meet high-altitude standards.
(vi) If 90 percent or more of the engine family sales will be in
California, a manufacturer may substitute emission-data vehicles
selected by the California Air Resources Board criteria for the
selections specified in paragraphs (b)(1) (i), (ii), and (iv) of this
section.
(vii)(A) Vehicles of each evaporative emission family will be
divided into evaporative emission control systems.
(B) The Administrator will select the vehicle expected to exhibit
the highest evaporative emissions, from within each evaporative family
to be certified, from among the vehicles represented by the exhaust
emission-data selections for the engine family, unless evaporative
testing has already been completed on the vehicle expected to exhibit
the highest evaporative emissions for the evaporative family as part of
another engine family's testing.
(C) If the vehicles selected in accordance with paragraph
(b)(1)(vii)(B) of this section do not represent each evaporative
emission control system then the Administrator will select the
[[Page 123]]
highest expected evaporative emission vehicle from within the
unrepresented evaporative system.
(viii) For high-altitude evaporative emission compliance for each
evaporative emission family, the manufacturer shall follow one of the
following procedures:
(A) The manufacturer will select for testing under high-altitude
conditions the one nonexempt vehicle previously selected under
paragraphs (b)(1)(vii) (B) or (C) of this section which is expected to
have the highest level of evaporative emissions when operated at high
altitude or
(B) In lieu of testing vehicles according to paragraph
(b)(1)(viii)(A) of this section, a manufacturer may provide a statement
in its application for certification that based on the manufacturer's
engineering evaluation of such high-altitude emission testing as the
manufacturer deems appropriate,
(1) That all light-duty vehicles not exempt under Sec. 86.090-8(h)
comply with the emission standards at high altitude and
(2) That light-duty trucks sold for principal use at designated
high-altitude locations comply with the high-altitude emission
requirements, and that all light-duty trucks sold at low altitude, which
are not exempt under Sec. 86.090-9(g)(2), are capable of being modified
to meet high-altitude standards.
(ix) Vehicles selected under paragraph (b)(1)(v)(A) of this section
may be used to satisfy the requirements of (b)(1)(viii)(A) of this
section.
(x) Light-duty trucks only: (A) The manufacturer may reconfigure any
of the low-altitude emission-data vehicles to represent the vehicle
configuration required to be tested at high altitude.
(B) The manufacturer is not required to test the reconfigured
vehicle at low altitude.
(2) Otto-cycle heavy-duty emission-data engines. Paragraph (b)(2) of
this section applies to Otto-cycle heavy-duty engines.
(i)-(ii) [Reserved]
(iii) The Administrator shall select a maximum of two engines within
each engine family based upon features indicating that they may have the
highest emission levels of the engines in the engine family as follows:
(A) The Administrator shall select one emission-data engine first
based on the largest displacement within the engine family. Then within
the largest displacement the Administrator shall select, in the order
listed, highest fuel flow at the speed of maximum rated torque, the
engine with the most advanced spark timing, no EGR or lowest EGR flow,
and no air pump or lowest actual flow air pump.
(B) The Administrator shall select one additional engine, from
within each engine family. The engine selected shall be the engine
expected to exhibit the highest emissions of those engines remaining in
the engine family. If all engines within the engine family are similar
the Administrator may waive the requirements of this paragraph.
(iv) If the engines selected in accordance with paragraphs (b)(2)
(ii) and (iii) of this section do not represent each engine
displacement-exhaust emission control system combination, then one
engine of each engine displacement-exhaust emission control system
combination not represented shall be selected by the Administrator.
(v) Within an engine family/displacement/control system, the
manufacturer may alter any emission-data engine (or other engine
including current or previous model year emission-data vehicles and
development engines provided they meet the emission-data engines
protocol) to represent more than one selection under paragraphs
(b)(2)(iii) of this section.
(3) Diesel heavy-duty emission-data engines. Paragraph (b)(3) of
this section applies to diesel heavy-duty emission-data vehicles.
(i) Engines will be chosen to be run for emission data based upon
engine family groupings. Within each engine family, the requirements of
this paragraph must be met.
(ii) Engines of each engine family will be divided into groups based
upon their exhaust emission control systems. One engine of each engine
system combination shall be run for smoke emission data (diesel engines
only) and
[[Page 124]]
gaseous emission data. Either the complete gaseous emission test or the
complete smoke test may be conducted first. Within each combination, the
engine that features the highest fuel feed per stroke, primarily at the
speed of maximum rated torque and secondarily at rated speed, will
usually be selected. If there are military engines with higher fuel
rates than other engines in the same engine system combinations, then
one military engine shall also be selected. The engine with the highest
fuel feed per stroke will usually be selected.
(iii) The Administrator may select a maximum of one additional
engine within each engine-system combination based upon features
indicating that it may have the highest emission levels of the engines
of that combination. In selecting this engine, the Administrator will
consider such features as the injection system, fuel system, compression
ratio, rated speed, rated horsepower, peak torque speed, and peak
torque.
(iv) Within an engine family control system combination, the
manufacturer may alter any emission-data engine (or other engine
including current or previous model year emission-data vehicles and
development engines provided they meet the emission-data engines'
protocol) to represent more than one selection under paragraphs (b)(3)
(ii) and (iii) of this section.
(c) Durability data--(1) Light-duty vehicle durability-data
vehicles. Paragraph (c)(1) of this section applies to light-duty vehicle
durability-data vehicles.
(i) A durability-data vehicle will be selected by the Administrator
to represent each engine-system combination. The vehicle selected shall
be of the engine displacement with the largest projected sales volume of
vehicles with that control-system combination in that engine family and
will be designated by the Administrator as to transmission type, fuel
system, inertia weight class, and test weight.
(ii) A manufacturer may elect to operate and test additional
vehicles to represent any engine-system combination. The additional
vehicles must be of the same engine displacement, transmission type,
fuel system and inertia weight class as the vehicle selected for that
engine-system combination in accordance with the provisions of paragraph
(c)(1)(i) of this section. Notice of an intent to operate and test
additional vehicles shall be given to the Administrator no later than 30
days following notification of the test fleet selection.
(2) Light-duty trucks. Paragraph (c)(2) of this section applies to
vehicles, engines, subsystems, or components used to establish exhaust
emission deterioration factors for light-duty trucks.
(i) The manufacturer shall select the vehicles, engines, subsystems,
or components to be used to determine exhaust emission deterioration
factors for each engine-family control system combination. Whether
vehicles, engines, subsystems, or components are used, they shall be
selected so that their emissions deterioration characteristics may be
expected to represent those of in-use vehicles, based on good
engineering judgment.
(ii) [Reserved]
(3) Heavy-duty engines. Paragraph (c)(3) of this section applies to
engines, subsystems, or components used to establish exhaust emission
deterioration factors for heavy-duty engines.
(i) The manufacturer shall select the engines, subsystems, or
components to be used to determine exhaust emission deterioration
factors for each engine-family control system combination. Whether
engines, subsystems, or components are used, they shall be selected so
that their emissions deterioration characteristics may be expected to
represent those of in-use engines, based on good engineering judgment.
(ii) [Reserved]
(d) For purposes of testing under Sec. 86.084-26 (a)(9) or (b)(11),
the Administrator may require additional emission-data vehicles (or
emission-data engines) and durability-data vehicles (light-duty vehicles
only) identical in all material respects to vehicles (or engines)
selected in accordance with paragraphs (b) and (c) of this section,
provided that the number of vehicles (or engines) selected shall not
increase the size of either the emission-data fleet or the durability-
data fleet by more than 20 percent or one vehicle (or engine), whichever
is greater.
[[Page 125]]
(e)(1) Any manufacturer whose projected sales for the model year in
which certification is sought is less than:
(i) 2,000 Otto-cycle light-duty vehicles, or
(ii) 2,000 diesel light-duty vehicles, or
(iii) 2,000 Otto-cycle light-duty trucks, or
(iv) 2,000 diesel light-duty trucks, or
(v) 2,000 Otto-cycle heavy-duty engines, or
(vi) 2,000 diesel heavy-duty engines, may request a reduction in the
number of test vehicles (or engines) determined in accordance with the
foregoing provisions of this section. The Administrator may agree to
such lesser number as he determines would meet the objectives of this
procedure.
(2) Any manufacturer may request to certify engine families with
combined total sales of fewer than 10,000 light-duty vehicles, light-
duty trucks, and heavy-duty engines utilizing assigned deterioration
factors prescribed by the Administrator. The assigned deterioration
factors shall be applied only to entire engine families.
(f) In lieu of testing an emission-data or durability-data vehicle
(or engine) selected under paragraph (b) or (c) of this section, and
submitting data therefore, a manufacturer may, with the prior written
approval of the Administrator, submit exhaust emission data and/or fuel
evaporative emission data, as applicable on a similar vehicle (or
engine) for which certification has previously been obtained or for
which all applicable data required under Sec. 86.090-23 has previously
been submitted.
(g)(1) This paragraph applies to light-duty vehicles and light-duty
trucks, but does not apply to the production vehicles selected under
paragraph (h) of this section.
(2)(i) Where it is expected that more than 33 percent of a carline,
within an engine-system combination will be equipped with an item
(whether that item is standard equipment or an option), the full
estimated weight of that item shall be included in the curb weight
computation for each vehicle available with that option in that carline,
within that engine-system combination.
(ii) Where it is expected that 33 percent or less of the carline,
within an engine-system, will be equipped with an item of (whether that
item is standard equipment or an option), no weight for that item will
be added in computing curb weight for any vehicle in that carline,
within that engine-system combination, unless that item is standard
equipment on the vehicle.
(iii) In the case of mutually exclusive options, only the weight of
the heavier option will be added in computing curb weight.
(iv) Optional equipment weighing less than 3 pounds per item need
not be considered.
(3)(i) Where it is expected that more than 33 percent of a carline,
within an engine-system combination will be equipped with an item of
(whether that item is standard equipment or an option) that can
reasonably be expected to influence emissions, then such items shall
actually be installed (unless excluded under paragraph (g)(3)(ii) of
this section) on all emission data and durability data vehicles of that
carline, within that engine-system combination, on which the items are
intended to be offered in production. Items that can reasonably be
expected to influence emissions are: air conditioning, power steering,
power brakes and other items determined by the Administrator.
(ii) If the manufacturer determines by test data or engineering
evaluation that the actual installation of the optional equipment
required by paragraph (g)(3)(i) of this section does not affect the
emissions or fuel economy values, the optional equipment need not be
installed on the test vehicle.
(iii) The weight of the options shall be included in the design curb
weight and also be represented in the weight of the test vehicles.
(iv) The engineering evaluation, including any test data, used to
support the deletion of optional equipment from test vehicles, shall be
maintained by the manufacturer and shall be made available to the
Administrator upon request.
(4) Where it is expected that 33 percent or less of a carline,
within an engine system combination will be equipped with an item of
(whether that
[[Page 126]]
item is standard equipment or an option) that can reasonably be expected
to influence emissions, that item shall not be installed on any emission
data or durability data vehicles of that carline, within that engine-
system combination, unless that item is standard equipment on the
vehicle.
(h) Alternative Durability Program durability-data vehicles. This
section applies to light-duty vehicle and light-duty truck durability-
data vehicles selected under the Alternative Durability Program
described in Sec. 86.085-13.
(1) In order to update the durability data to be used to determine a
deterioration factor for each engine family group, the Administrator
will select durability-data vehicles from the manufacturer's production
line. Production vehicles will be selected from each model year's
production for those vehicles certified using the Alternative Durability
Program procedures.
(i) The Administrator shall select the production durability-data
vehicle designs from the designs that the manufacturer offers for sale.
For each model year and for each engine family group, the Administrator
may select production durability-data vehicle designs of equal number to
the number of engine families within the engine family group, up to a
maximum of three vehicles.
(ii) The production durability-data vehicles representing the
designs selected in paragraph (h)(1)(i) of this section will be randomly
selected from the manufacturer's production. The Administrator will make
these random selections unless the manufacturer (with prior approval of
the Administrator) elects to make the random selections.
(iii) The manufacturer may select additional production durability-
data vehicle designs from within the engine family group. The production
durability-data vehicles representing these designs shall be randomly
selected from the manufacturer s production in accordance with paragraph
(h)(l)(ii) of this section.
(iv) For each production durability-data vehicle selected under
paragraph (h)(1) of this section, the manufacturer shall provide to the
Administrator (before the vehicle is tested or begins service
accumulation) the vehicle identification number. Before the vehicle
begins service accumulation the manufacturer shall also provide the
Administrator with a description of the durability-data vehicle as
specified by the Administrator.
(v) In lieu of testing a production durability-data vehicle selected
under paragraph (h)(1) of this section, and submitting data therefrom, a
manufacturer may, with the prior written approval of the Administrator,
submit exhaust emission data from a production vehicle of the same
configuration for which all applicable data has previously been
submitted.
(2) If, within an existing engine family group, a manufacturer
requests to certify vehicles of a new design, engine family, emission
control system, or with any other durability-related design difference,
the Administrator will determine if the existing engine family group
deterioration factor is appropriate for the new design. If the
Administrator cannot make this determination or deems the deterioration
factor not appropriate, the Administrator shall select preproduction
durability-data vehicles under the provisions of paragraph (c) of this
section. If vehicles are then certified using the new design, the
Administrator may select production vehicles with the new design under
the provisions of paragraph (h)(1) of this section.
(3) If a manufacturer reguests to certify vehicles of a new design
that the Administrator determines are a new engine family group, the
Administrator shall select preproduction durability data vehicles under
the provisions of paragraph (c) of this section. If vehicles are then
certified using the new design, the Administrator may select production
vehicles of that design under the provisions of paragraph (h)(1) of this
section.
[54 FR 14474, Apr. 11, 1989, as amended at 55 FR 30618, July 26, 1990]