Global Technical Regulation No. 23
|Name:||Global Technical Regulation No. 23|
|Description:||Measurement Procedure for Two- and Three-wheeled Vehicles Equipped with a Combustion Engine with Regard to Durability of Pollution-control Devices.|
|Official Title:||United Nations Global Technical Regulation on the Measurement Procedure for Two- and Three-wheeled Vehicles Equipped with a Combustion Engine with Regard to Durability of Pollution-control Devices.|
|Country:||ECE - United Nations|
|Date of Issue:||2022-09-05|
|Number of Pages:||46|
|Vehicle Types:||Component, Motorcycle|
|Subject Categories:||Emissions and Fuel Consumption|
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September 5, 2022
Created on November 18, 2004, Pursuant to Article 6 of the
AGREEMENT CONCERNING THE ESTABLISHING OF GLOBAL TECHNICAL
REGULATIONS FOR WHEELED VEHICLES, EQUIPMENT AND PARTS WHICH
CAN BE FITTED AND/OR BE USED ON WHEELED VEHICLES
(ECE/TRANS/132 and Corr.1)
DONE AT GENEVA ON JUNE 25, 1998
UNITED NATIONS GLOBAL TECHNICAL REGULATION NO. 23
UNITED NATIONS GLOBAL TECHNICAL REGULATION ON
THE MEASUREMENT PROCEDURE FOR TWO- AND THREE-WHEELED VEHICLES
EQUIPPED WITH A COMBUSTION ENGINE WITH REGARD TO
DURABILITY OF POLLUTION-CONTROL DEVICES
(ESTABLISHED IN THE GLOBAL REGISTRY ON JUNE 22, 2022)
I. STATEMENT OF TECHNICAL RATIONALE AND JUSTIFICATION
1. The industry producing two- and three-wheeled vehicles in the scope of this United Nations
Global Technical Regulation (UN GTR) is a global one, with companies selling their
products in many different countries. The Contracting Parties to the 1998 Agreement have
determined that work should be undertaken to address the environmental performance
requirements from two- and three-wheeled vehicles of Category 3 as a way to help improve
air quality internationally.
2. The aim of this UN GTR is to provide measures to strengthen the world-harmonization of
light motor vehicle approval and certification legislation, in order to improve the cost
effectiveness of environmental performance testing, remove trade barriers, reduce the
overall complexity of global legislation, remove potential areas of conflict or opposing
requirements and improve the air quality.
3. In the framework of the 1998 Agreement and under continued work by the Informal Working
Group (IWG) on Environmental and Propulsion Performance Requirements of L-category
vehicles (EPPR), the objective of this Document is to propose a new UN GTR on the
measurement procedure for two- and three-wheeled vehicles equipped with a combustion
engine with regard to durability of pollution-control devices.
4. The IWG on EPPR also considered alignment with the work done by the IWG on Worldwide
harmonized Light Vehicles Test Procedure (WLTP) if deemed advantageous, to ensure
harmonization and to avoid any duplication of effort.
5. This UN GTR is based on the work of the IWG on EPPR, which held its first meeting during
the sixty-fifth GRPE in January 2013 and on the initial proposal by the European Union (EU,
represented by the European Commission (EC)).
B. PROCEDURAL BACKGROUND
6. The EU put forward and announced their intention of setting up a working group during the
sixty-third and sixty-fourth meetings of GRPE in January and June 2012 and in the
157th session of WP.29 in June 2012.
7. The authorisation to develop the above UN GTR was requested at the 62nd session of
GRPE in January 2021 with document number GRPE-82-26-Rev.1, which was submitted for
adoption to the 184th session of WP.29 in June 2021 as document number
8. At the 85th GRPE session in January 2022, a formal proposal for this new UN GTR was
tabled for adoption (ECE/TRANS/WP29/GRPE/2022/7). Subsequently the proposal was
prepared for submission to the June 2022 session of WP.29 for adoption by the Executive
Committee for the 1998 Agreement (AC.3).
9. Ongoing developments of test types and procedures and global discussion on
harmonization have resulted in the technical requirements contained within this UN GTR.
The final text of the UN GTR is presented in Section II of this Document.
Road vehicle Act, Article 41 "Systems and Devices of Motor Vehicles";
Safety Regulations for Road Vehicles, Article 31 "Emission Control
Enforcement procedure for motor vehicle type certification, additional
Rule 7 on "Durability driving enforcement procedure".
United States of America:
US Code of Federal Regulations (CFR) Title 40, Part 86 Subpart E&F;
California Air Resources Board regulations on durability as contained in
California Code of Regulations Title 13 Section 1958(c).
ISO 11486 (Motorcycles - Chassis dynamometer setting method);
ISO 4164 (Mopeds - Engine test code - Net power);
ISO 4106 (Motorcycles - Engine test code - Net power).
ISO 7116 (Mopeds - Measurement method for maximum speed)
ISO 7117 (Motorcycles - Measurement method for maximum speed)
11. Most of these regulations had been in existence for many years and the methods of
measurement varied significantly. The technical experts were familiar with these
requirements and discussed them in their working sessions. The IWG on EPPR
therefore considered that to be able to determine a two- and three-wheeled vehicle's
real impact on the environment, in terms of its exhaust pollutant emissions and
energy efficiency, the test procedure and consequently the UN GTR No. 2 needs to
represent modern, real-world vehicle operation.
15. The IWG on EPPR has discussed at length which vehicle types should be in the
scope of the UN GTR. One of the objectives of the group was to discuss the
substantive requirements of two-wheeled vehicles first followed by a discussion if
these requirements should as well be applied to three-wheeled vehicles. In particular
it was debated whether or not the classification criteria laid down in Paragraph 2 of
Special Resolution No. 1 (S.R.1) on Category 3 vehicles should be referenced in
detail or using a more generic wording, e.g. two- and three-wheeled vehicles allowing
for more flexibility to allow alignment with domestic classification of three-wheeled
16. The IWG on EPPR discussed possible solutions how three-wheeled vehicles could be
included in the scope of the UN GTR given the fact that S.R.1 contains recommended
classification criteria for category 3 vehicles that might require an update for technical
progress. Finally it was agreed to put "Category 3" vehicles in Paragraph 2 of
the UN GTR, to reference S.R.1 in a footnote and to state the following with respect
to the classification of a three-wheeled vehicle:
"With regard to a three-wheeled vehicle of Category 3-4 or 3-5, Contracting Parties
agree that at a minimum the following criteria should be taken into account for vehicle
In their straight-ahead condition, motor vehicles having two wheels which are
placed on the same straight line and equipped with one sidecar; or
Motor vehicles having a saddle-type seat, a handle-bar type steering system
and three wheels, on which the side of the driver's seat is of open structure."
17. Contracting Parties may expand the scope to other types of three-wheeled vehicles in
order to align with their domestic classifications of three-wheeled vehicles as deemed
18. The definitions used in the UN GTR are aligned as much as possible with definitions
in international legislation and from the work of the Vehicle Propulsion System
Definitions (VPSD) group operating under GRPE with the goal to harmonize high
level powertrain definitions as well as from other regional legislation as listed in
23. Contracting Parties may continue using reference fuels currently in use in their
countries for the principal performance requirements in Paragraph 7 of Amendment 5
to UN GTR No. 2 on condition that their equivalence with the reference fuel in
Appendix 2 to Annex 4. of Amendment 5 to UN GTR No. 2 in terms of emissions is
24. The alternative performance requirements in Paragraph 7 of Amendment 5 to
UN GTR No. 2 are applicable with the corresponding reference fuels.
8. REGULATORY IMPACT AND ECONOMIC EFFECTIVENESS
25. ANTICIPATED BENEFITS.
Increasingly two- and three-wheeled vehicles are being prepared for the world
market. To the extent that manufacturers are preparing substantially different models
in order to meet different emission regulations and methods of measuring CO
emission and fuel or energy consumption, testing costs and other production values
are increased. It would be more economically efficient to have manufacturers using a
similar test procedure worldwide wherever possible to prove satisfactory
environmental performance before placing a product on the market. It is anticipated
that the test procedures in this UN GTR will provide a common test programme for
manufacturers to use in countries worldwide and thus reduce the amount of
resources utilised to test vehicles. These savings will accrue not only to the
manufacturers, but more importantly, to the consumers and the authorities as well.
However, developing a test programme just to address the economic question does
not completely address the mandate given when work on this UN GTR was first
started. The test programme also improves the state of testing vehicles, reflects
better how vehicles are used today and covers recent and near-future powertrain
technologies, fuels and emission abatement technologies.
9. POTENTIAL COST EFFECTIVENESS
26. At the time of writing this UN GTR, the data is not available to undertake a full impact
assessment of the test types contained. This is in part because not all limit values
have been set out and it is undecided to what level the proposed upgrade of test
procedures will be accepted by Contracting Parties. Specific cost effectiveness values
can be quite different, depending on the national or regional environmental needs and
market situation. While there are no calculated values here, the belief of the technical
group is that there are clear and significant benefits comparing to justifiable,
anticipated cost increases associated with this UN GTR. Finally allowing not only all
two- but also three- wheeled vehicles to be tested according to a dynamic, real-world
emission laboratory test-cycle will much better reflect the actual environmental
performance of light motor vehicles including pollutant emissions and energy
efficiency measurement results, allowing the gap between claimed and actual,
real-world environmental performance experienced by citizens to be narrowed.
1.5. General Requirements Test Type V
1.5.1. Manufacturers shall ensure that certification requirements for verifying durability
requirements are met. At the choice of the manufacturer one of the following durability
test procedures shall be used to provide evidence to the responsible authority that the
environmental performance of a certified vehicle is durable:
22.214.171.124. Actual durability testing with full mileage accumulation:
The test vehicles shall physically accumulate the full mileage set out in Paragraph 2.4. and
shall be tested in accordance with the procedure laid down in Paragraph 2.3.1. The
emission test results up to and including the full mileage set out in Paragraph 2.4. shall be
lower than the emission limits set out in Paragraph 7 of Amendment 5 to UN GTR No. 2;
126.96.36.199. Actual durability testing with partial mileage accumulation:
The test vehicles shall physically accumulate a minimum of 50% of the full mileage set
out in Paragraph 2.4. and shall be tested in accordance with the procedure laid down in
Paragraph 2.3.2. The test results shall be extrapolated up to the full mileage set out in
Paragraph 2.4. Both the test results and the extrapolated results shall be lower than the
performance limits set out in Paragraph 7 of Amendment 5 to UN GTR No. 2;
188.8.131.52. Mathematical durability procedure:
For each emission constituent, the product of the multiplication of the deterioration
factor set out in Paragraph 2.5. and the environmental test result of a vehicle which has
accumulated more than 2,500km for a vehicle with a maximum design vehicle speed of
<130km/h and 3,500km for a vehicle with a maximum design vehicle speed of
≥130km/h after it was first started at the end of the production line shall be lower than
the environmental limits set out in Paragraph 7 of Amendment 5 to UN GTR No. 2.
1.5.2. The test vehicle(s) to demonstrate durability of the pollution-control devices shall
comply with the requirements laid down in Annex 5. The test vehicles' powertrain and
pollution-control device type fitted on the test vehicles shall be documented and listed
by the manufacturer. The list shall include at a minimum such items as the
specifications of the propulsion type and its powertrain, where applicable, the exhaust
oxygen sensor(s), catalytic converter(s) type, particulate filter(s) or other
pollution-control devices, intake and exhaust systems and any peripheral device(s) that
may have an impact on the environmental performance of the certified vehicle. This
documentation shall be added to the test report.
1.5.3. The manufacturer shall provide evidence of the possible impacts on Test Type V
results of any modification to the emission abatement system configuration, the
pollution-control device type specifications or other peripheral device(s) interacting with
the pollution-control devices, in production of the vehicle after environmental
performance certification. The manufacturer shall provide the responsible authority with
this documentation and evidence upon request in order to prove that the durability
performance of the vehicle with regard to environmental performance will not be
negatively affected by any change in vehicle production, retrospective changes in the
vehicle configuration, changes in the specifications of any pollution-control device type,
or changes in peripheral devices fitted on the certified vehicle.
2.2. Specific Requirements Test Type V
2.2.1. In the Type V test procedure, mileage shall be accumulated by driving the test vehicles
either on a test track, on the road or on a chassis dynamometer. The test track or test
road shall be selected at the discretion of the manufacturer.
184.108.40.206. Chassis Dynamometer Used for Mileage Accumulation
220.127.116.11.1. Chassis dynamometers used to accumulate Test Type V durability mileage shall
enable the durability mileage accumulation driving schedule laid down in Annexes 1
or 2, as applicable, to be carried out.
18.104.22.168.2. In particular, the dynamometer shall be equipped with systems simulating the same
inertia and resistance to progress as those used in the Type I emission laboratory test
laid down in Annex 1 of Amendment 5 to UN GTR No. 2. Emission analysis equipment
is not required for mileage accumulation. The same inertia and flywheel settings and
calibration procedures shall be used for the chassis dynamometer referred to in
Annex 1 of Amendment 5 to UN GTR No. 2, used to accumulate mileage with the test
22.214.171.124.3. The test vehicle may be moved to a different bench in order to conduct Type I emission
verification tests. The mileage accumulated in the Type I emission verification tests
may be added to the total accumulated mileage.
2.2.2. The Type I emission verification tests before, during and after durability mileage
accumulation shall be conducted according to the test procedures for emissions after
cold start set out in Annex 1. of Amendment 5 to UN GTR No. 2. All Type I emission
verification test results shall be listed and made available to the responsible authority
upon request. The results of Type I emission verification tests at the start and the finish
of durability mileage accumulation shall be included in the test report. At least the first
and last Type I emission verification tests shall be conducted or witnessed by the
technical service and reported to the responsible authority. The test report shall confirm
and state whether the technical service conducted or witnessed the Type I emission
2.3. Test Type V, Pollution-control Device Durability Test Procedure Specifications
The specifications of the three alternative durability test procedures are as follows:
2.3.1. Actual Durability Testing with Full Mileage Accumulation
The durability test procedure with full mileage accumulation to age the test vehicles
shall refer to Paragraph 126.96.36.199. Full mileage accumulation shall mean full completion
of the assigned test mileage laid down in Paragraph 2.4. by repeating the driving
manoeuvres laid down in Annex 1. or, if applicable in Annex 2.
188.8.131.52. The manufacturer shall provide evidence that the emission limits in the applicable
Type I emission laboratory test cycle, as set out in Paragraph 7 of Amendment 5 to
UN GTR No. 2, of the aged test vehicles are not exceeded when starting mileage
accumulation, during the accumulation phase and after full mileage accumulation has
Test Type V – Durability Test Procedure with Partial Mileage Accumulation
Accelerated Durability Test Procedure, Partial Mileage Accumulation
184.108.40.206. Stop Criteria for the Durability Test Procedure with Partial Mileage Accumulation.
Partial mileage accumulation may stop if the following criteria are met:
220.127.116.11.1. if a minimum of 50% of the applicable test mileage laid down in Paragraph 2.4. has
been accumulated; and
18.104.22.168.2. if all the Type I emission verification test results are below the emission limits laid down
in Paragraph 7 of Amendment 5 to UN GTR No. 2 at all times during the partial mileage
accumulation phase; or
22.214.171.124.3. if the manufacturer cannot prove that the stop criteria in Paragraph 126.96.36.199.1.
and 188.8.131.52.2. are met, the mileage accumulation shall continue to the point where
those criteria are met or to the full durability mileage laid down in Paragraph 2.4.
184.108.40.206. Data Processing and Reporting for the Durability Test Procedure with Partial Mileage
220.127.116.11.1. The manufacturer shall use the arithmetic mean of the Type I emission test results at
each test interval, with a minimum of one emission tests per test interval. All Type I
emissions test results shall be plotted per THC, CO, NO , and if applicable NMHC
and PM, emission constituent, against accumulation mileage rounded to the nearest
kilometre. If more than one test per test interval is performed, then an arithmetic mean
shall be used.
18.104.22.168.2. The best fit linear line (trend line: y = ax+b) shall be fitted and drawn through all these
data points based on the method of least squares. This best-fit straight trend line shall
be extrapolated over the full durability mileage laid down in Paragraph 2.4. At the
request of the manufacturer, the trend line may start as of 20% of the durability mileage
laid down in Paragraph 2.4., in order to take into account possible run-in effects of the
2.3.3. Mathematical Durability Procedure
The mathematical durability procedure shall refer to Paragraph 22.214.171.124.
126.96.36.199. The emission results of the vehicle that has accumulated more than the mileage
prescribed in Paragraph 188.8.131.52. after it was first started at the end of the production
line, the applied deterioration factors set out in Paragraph 2.5., and the product of the
multiplication of both and the emission limit set out in Paragraph 7 of Amendment 5 to
UN GTR No. 2 shall be added to the test report.
2.3.4. Durability Mileage Accumulation Driving Schedules.
One of the following two durability mileage accumulation driving schedules shall be
conducted to age the test vehicle until the assigned test mileage laid down in
Paragraph 2.4. is fully completed according to the full mileage accumulation test
procedure set out in Paragraph 2.3.1. or partially completed according to the partial
mileage accumulation test procedure in Paragraph 2.3.2.:
184.108.40.206. The Standard Road Cycle (SRC-LeCV) for Two- and Three-wheeled Vehicles
The Standard Road Cycle (SRC-LeCV) custom tailored for two- and three-wheeled
vehicles is the principle durability Type V test cycle composed of a set of four mileage
accumulation durability cycles. One of these durability mileage accumulation cycles
shall be used to accumulate mileage by the test vehicle(s) according to the technical
details laid down in Annex 1.
220.127.116.11. The USA EPA Approved Mileage Accumulation Cycle (AMA)
At the choice of the manufacturer, the AMA durability mileage accumulation cycle may
be conducted as alternative Type V mileage accumulation cycle. The AMA durability
mileage accumulation cycle shall be conducted according to the technical details laid
down in Annex 2.
18.104.22.168. Bench Ageing Durability Test.
22.214.171.124.1. At the option of the Contracting Party, as an alternative to Paragraph 2.3.1. or 2.3.2.,
the manufacturer may request to use the bench ageing procedure laid down in
Annex 3. The bench ageing durability test, as laid down in Annex 3, shall determine the
emissions of an aged vehicle by means of ageing the vehicle catalyst with the Standard
Bench Cycle (SBC) to produce the same amount of deterioration experienced by the
catalyst due to thermal deactivation over the assigned test mileage test laid down in
126.96.36.199.2. The emission results of the vehicle that has accumulated more than 100km after it was
first started at the end of the production line and the deterioration factors as determined
using the procedure as set out in Annex 3 shall not exceed the emission limits in the
applicable Type I emission laboratory test cycle, as set out in Paragraph 7 of
Amendment 5 to UN GTR No. 2. The emission results of the vehicle that has
accumulated more than 100km after it was first started at the end of the production line,
the deterioration factors as determined using the procedure as set out in Annex 3, the
total emissions (calculated with the multiplication or additive equations), and the
emission limit set out in Paragraph 7 of Amendment 5 to UN GTR No.2 shall be added
to the test report.
2.4. Minimum Mileage Accumulation Requirements
2.4.1. The minimum mileage accumulation with regard to Test Type V is set out in
2.4.2. The Minimum Mileage Accumulation
The gaseous pollutant emissions for each class of vehicle set out in Paragraph 3 of
Amendment 5 to UN GTR No. 2, obtained when tested in accordance with the
applicable emission laboratory test cycle specified in Appendix 12 to Annex 4 of
Amendment 5 to UN GTR No. 2, shall not exceed the limit values specified in
Paragraph 7 of Amendment 5 to UN GTR No. 2 when verifying tailpipe emissions
during mileage accumulation according to Annex 1 or 2. and after having completed the
applicable mileage set out in Table 2.
Minimum Durability Mileage Accumulation (km)
Two-wheeled vehicles ≤50 ≤25 5,500
≤50 >25, ≤50 11,000
≤50 >50, <100
>50, <150 <100
<150 ≥100, <115
– ≥115, <130
– ≥130, <140
Three-wheeled vehicles ≤50 ≤50 11,000
2.5. Deterioration Factors for the Mathematical Durability Procedure
2.5.1. At the option of the Contracting Party, as an alternative to Paragraph 2.3.1. or 2.3.2,
the manufacturer may request to use the mathematical durability procedure laid down
in Paragraph 2.3.3. The multiplicative deterioration factors for the mathematical
durability procedure are set out in Table 4.
THE STANDARD ROAD CYCLE DURABILITY TEST FOR TWO- AND THREE-WHEELED VEHICLES
1.1. The Standard Road Cycle for two- and three-wheeled Vehicles (SRC-LeCV) is a
representative mileage accumulation driving schedule to age vehicles and in particular their
pollution-control devices in a defined, repeatable and representative way. The test vehicles
may run the SRC-LeCV on the road, on a test track or on a mileage accumulation chassis
1.2. The SRC-LeCV shall consist of five laps of a 6km course. The length of the lap may be
changed to accommodate the length of the mileage accumulation test track or test road.
The SRC-LeCV shall include four different vehicle speed profiles.
1.3. The manufacturer may request to be allowed alternatively to perform the next higher
numbered test cycle, with the agreement of the responsible authority, if it considers that this
better represents the real-world use of the vehicle.
2. SRC-LECV MILEAGE ACCUMULATION TEST REQUIREMENTS
2.1. If the SRC-LeCV is performed on a mileage accumulation chassis dynamometer:
2.1.1. the chassis dynamometer shall be equipped with systems equivalent to those used in the
Type I emission laboratory test set out in Annex 1. of Amendment 5 to UN GTR No. 2,
simulating the same inertia and resistance to progress. Emission analysis equipment shall
not be required for mileage accumulation. The same inertia and flywheel settings and
calibration procedures shall be used for the chassis dynamometer used to accumulate
mileage with the test vehicles set out in Annex 1 of Amendment 5 to UN GTR No. 2;
2.1.2. the test vehicles may be moved to a different chassis dynamometer in order to conduct
Type I emission verification tests. This dynamometer shall enable the SRC-LeCV to be
2.1.3. the chassis dynamometer shall be configured to give an indication after each quarter of the
6km course has been passed that the test driver or robot driver shall proceed with the next
set of actions;
2.1.4. a timer displaying seconds shall be made available for execution of the idling periods;
2.1.5. the mileage travelled shall be calculated from the number of rotations of the roller and the
2.4. No stopping is permitted mid-cycle. Any stops for Type I emission tests, maintenance, soak
periods, refuelling, etc. shall be performed at the end of one complete SRC-LeCV sub-cycle,
i.e. the culmination of Step 47 in Table A1/4. If the vehicle travels to the testing area under
its own power, only moderate acceleration and deceleration shall be used and the vehicle
shall not be operated at full throttle.
2.5. The four cycles shall be selected on the basis of the maximum design vehicle speed of the
vehicle and the engine capacity.
2.6. For the purpose of accumulating mileage in the SRC-LeCV, the test vehicles shall be
grouped as follows:
Two- and Three-wheeled Vehicles Groups for SRC-LeCV
SRC Cycle classification Engine displacement (cc) Max. speed (km/h)
1 ≤50 >50, <100
>50, <150 <100
2 <150 ≥100, <115
– ≥115, <130
3 – ≥130, <140
4 – ≥140
the acceleration capability of the vehicle is not sufficient to carry out the acceleration
phases within the prescribed mileage; or
the prescribed maximum vehicle speed in the individual cycles cannot be achieved
owing to a lack of propulsion power; or
the maximum design vehicle speed is restricted to a vehicle speed lower than the
prescribed SRC-LeCV vehicle speed
the vehicle shall be driven with the accelerator device fully open until the vehicle speed
prescribed for the test cycle is reached or until the limited maximum design vehicle speed is
reached. Subsequently the test cycle shall be carried out as prescribed for the vehicle
Significant or frequent deviations from the prescribed vehicle speed tolerance band and the
associated justification shall be reported to the responsible authority and be included in the
Type V test report.
2.7.4. Cruise Instruction:
188.8.131.52. if the following action is 'cruise', the vehicle may be accelerated to attain the target vehicle
184.108.40.206. the throttle shall continue to be operated as required to attain and remain at the target
cruising vehicle speed.
2.7.5. A driving instruction shall be performed in its entirety. Additional idling time, acceleration to
above, and deceleration to below, the target vehicle speed is permitted in order to ensure
that actions are performed fully.
2.7.6. Gear changes should be carried out according to the guidance laid down in Appendix 13 to
Annex 4 of Amendment 5 to UN GTR No. 2. Alternatively, guidance provided by the
manufacturer to the consumer may be used if certified by the responsible authority.
2.7.7. Where the test vehicle cannot reach the target vehicle speeds set out in the applicable
SRC-LeCV, it shall be operated at wide open throttle and using other available options to
attain maximum design vehicle speed.
2.8. SRC-LeCV Test Steps
The SRC-LeCV test shall consist of the following steps:
2.8.1. the maximum design speed of the vehicle and either the engine capacity shall be obtained;
2.8.2. the required SRC-LeCV shall be selected from Table A1/1 and the required target vehicle
speeds and detailed driving instructions from Table A1/3 and Table A1/4.
2.8.3. the column 'decelerate by' shall indicate the delta vehicle speed to be subtracted either from
the previously attained target vehicle speed or from the maximum design vehicle speed,
whichever is lower.
2.8.5. In accordance with Paragraph 2.2.5., quarter divisions of the lap length shall be marked or
identified on the test track or road, or a system shall be used to indicate the mileage being
passed on the chassis dynamometer.
2.8.6. After each sub-lap is passed, the required list of actions of Table A1/3 and Table A1/4 shall
be performed in order and in accordance with Paragraph 2.7. regarding the general driving
instructions to or at the next target vehicle speed.
2.8.7. The maximum attained vehicle speed may deviate from the maximum design vehicle speed
depending on the type of acceleration required and track conditions. Therefore, during the
test the actual attained vehicle speeds shall be monitored to see if the target vehicle speeds
are being met as required. Special attention shall be paid to peak vehicle speeds and cruise
vehicle speeds close to the maximum design vehicle speed and the subsequent vehicle
speed differences in the decelerations.
2.8.8. Where a significant deviation is consistently found when performing multiple sub-cycles, the
target vehicle speeds shall be adjusted in the table in Paragraph 2.8.4. The adjustment
needs to be made only when starting a sub-cycle and not in real time.
2.9. SRC-LeCV Detailed Test Cycle Description
2.9.1. Graphical Overview of the SRC-LeCV
SRC-LeCV, Example Mileage Accumulation Characteristics for All Four Cycles
Table A1/3 (Continued)
Cycle: 1 2 3 4
(Cont) 2nd ½
Decelerate Moderate 15 20 25 35
Accelerate Moderate 50 75 80 105
Cruise 50 75 80 105
3 1st ½
Decelerate Moderate 25 15 15 25
Accelerate Moderate 50 90 95 120
Cruise 50 90 95 120
Decelerate Moderate 25 10 30 40
Accelerate Moderate 45 70 90 115
Cruise 45 70 90 115
2.9.3. Soak Procedures in the SRC-LeCV
The SRC-LeCV soak procedure shall consist of the following steps
220.127.116.11. a full SRC-LeCV sub-cycle (approximately 30km) shall be completed
18.104.22.168. a Test Type I emission test may be performed if deemed necessary for statistical relevance;
22.214.171.124. any required maintenance shall be undertaken and the test vehicle may be refuelled;
126.96.36.199. the test vehicle shall be set to idle with the combustion engine running for a minimum of one
hour with no user input;
188.8.131.52. the propulsion of the test vehicle shall be turned off
184.108.40.206. the test vehicle shall be cooled down and soaked under ambient conditions for a minimum
of six hours (or four hours with a fan and lubrication oil at ambient temperature);
220.127.116.11. the vehicle may be refuelled and mileage accumulation shall be resumed as required at
Lap 1, Sub-lap 1 of the SRC-LeCV sub-cycle in Table A1/3.
18.104.22.168. the SRC-LeCV soak procedure shall not replace the regular soak time for Type I emission
test laid down in Annex 1 of Amendment 5 to UN GTR No. 2. The SRC-LeCV soak
procedure may be coordinated so as to be performed after each maintenance interval or
after each emission laboratory test.
22.214.171.124. Test Type V soak procedure for actual durability testing with full mileage accumulation
126.96.36.199.1. During the full mileage accumulation phase set out in Paragraph 2.3.1. of this GTR, the test
vehicles shall undergo a minimum number of soak procedures set out in Table A1/5. These
procedures shall be evenly distributed over the accumulated mileage.
188.8.131.52.2. The number of soak procedures to be conducted during the full mileage accumulation phase
shall be determined according to the following table:
Number of Soak Procedure Depending on the SRC-LeCV in Table A1/1
SRC-LeCV, cycle No
1 & 2 3
Minimum number of Test Type V soak procedure
184.108.40.206. Test Type V Soak Procedure for Actual Durability Testing with Partial Mileage Accumulation
During the partial mileage accumulation phase set out in Paragraph 2.3.2. of this GTR, the
test vehicles shall undergo four soak procedures. These procedures shall be evenly
distributed over the accumulated mileage.
2.3. One AMA test sub-cycle shall be performed as follows:
2.3.1. Driving Schedule AMA Test Sub-sub-cycle
Driving Schedule AMA Test Sub-sub-cycle
2.3.10. At the manufacturer's request, and with the agreement of the responsible authority, should the
vehicle be unable to attain the specified cycle vehicle speeds for that class, the vehicle type shall
be placed in a lower class. If the vehicle is unable to achieve the cycle vehicle speeds required
for this lower class, it shall attain the highest possible vehicle speed during the test and full
throttle shall be applied if necessary to attain that vehicle speed.
2.4. Bench-ageing time. Bench ageing time shall be calculated using the Bench Ageing Time (BAT)
equation as follows:
te for a temperature bin = th*exp ((R/Tr) – (R/Tv))
Total te = Sum of te over all the temperature groups
bench ageing time = A *(Total te)
A = 1.1 This value adjusts the catalyst ageing time to account for deterioration from sources other
than thermal ageing of the catalyst.
R = Catalyst thermal reactivity = 18,500
th = The time (in hours) measured within the prescribed temperature bin of the vehicle's catalyst
temperature histogram adjusted to a full useful life basis e.g., if the histogram represented 400km,
and useful life is, in accordance with Paragraph 2.4. of this GTR, for example for Class 2 vehicle
20,000km; all histogram time entries would be multiplied by 50 (20,000/400).
Total te = The equivalent time (in hours) to age the catalyst at the temperature of Tr on the catalyst
ageing bench using the catalyst ageing cycle to produce the same amount of deterioration
experienced by the catalyst due to thermal deactivation over the use for live mileage specific for
the vehicle class in Paragraph 2.4. of this GTR, for example for Class 2 vehicle 20,000km
te for a temperature bin = The equivalent time (in hours) to age the catalyst at the temperature of
Tr on the catalyst ageing bench using the catalyst ageing cycle to produce the same amount of
deterioration experienced by the catalyst due to thermal deactivation at the temperature bin of Tv
over the use for live mileage specific for the vehicle class in Paragraph 2.4. of this GTR, for
example for Class 2 vehicle 20,000km
Tr = The effective reference temperature (in °K) of the catalyst on the catalyst bench run on the
bench ageing cycle. The effective temperature is the constant temperature that would result in the
same amount of ageing as the various temperatures experienced during the bench ageing cycle.
Tv = The mid-point temperature (in °K) of the temperature bin of the vehicle on-road catalyst
STANDARD BENCH CYCLE (SBC)
The standard ageing durability procedure consists of ageing a catalyst/oxygen sensor system on
an ageing bench which follows the Standard Bench Cycle (SBC) described in this Annex. The
SBC requires use of an ageing bench with an engine as the source of feed gas for the catalyst.
The SBC is a 60s cycle which is repeated as necessary on the ageing bench to conduct ageing for
the required period of time. The SBC is defined based on the catalyst temperature, engine air/fuel
(A/F) ratio, and the amount of secondary air injection which is added in front of the first catalyst.
2. CATALYST TEMPERATURE CONTROL
2.1. Catalyst temperature shall be measured in the catalyst bed at the location where the highest
temperature occurs in the hottest catalyst. Alternatively, the feed gas temperature may be
measured and converted to catalyst bed temperature using a linear transform calculated from
correlation data collected on the catalyst design and ageing bench to be used in the ageing
2.2. Control the catalyst temperature at stoichiometric operation (1 to 40s on the cycle) to a minimum
of 800°C (±10°C) by selecting the appropriate engine speed, load, and spark timing for the engine.
Control the maximum catalyst temperature that occurs during the cycle to 890°C (±10°C) by
selecting the appropriate A/F ratio of the engine during the 'rich' phase described in the table
2.3. If a low control temperature other than 800°C is utilized, the high control temperature shall be
90°C higher than the low control temperature.
Standard Bench Cycle (SBC)
Engine air/fuel ratio
1-40 Stoichiometric, with load, spark timing, and engine speed controlled
to achieve a minimum catalyst temperature of 800°C
41-45 "Rich" (A/F ratio selected to achieve a maximum catalyst
temperature over the entire cycle of 890°C, or 90° higher than low
46-55 "Rich" (A/F ratio selected to achieve a maximum catalyst
temperature over the entire cycle of 890°C, or 90° higher than low
56-60 Stoichiometric, same load, spark timing, and engine speed as used
in the 1-40s period of the cycle
3.3. Temperature measurement. Catalyst temperature shall be measured using a thermocouple placed
in the catalyst bed at the location where the highest temperature occurs in the hottest catalyst.
Alternatively, the feed gas temperature just before the catalyst inlet face may be measured and
converted to catalyst bed temperature using a linear transform calculated from correlation data
collected on the catalyst design and ageing bench to be used in the ageing process. The catalyst
temperature shall be stored digitally at the speed of 1Hz (one measurement per second).
3.4. Air/Fuel measurement. Provisions shall be made for the measurement of the air/fuel (A/F) ratio (such
as a wide-range oxygen sensor) as close as possible to the catalyst inlet and outlet flanges. The
information from these sensors shall be stored digitally at the speed of 1Hz (one measurement per
3.5. Exhaust flow balance. Provisions shall be made to assure that the proper amount of exhaust
(measured in grams/second at stoichiometry, with a tolerance of ±5g/s) flows through each
catalyst system that is being aged on the bench.
The proper flow rate is determined based upon the exhaust flow that would occur in the original
vehicle's engine at the steady state engine speed and load selected for the bench ageing in
3.6. Setup. The engine speed, load, and spark timing are selected to achieve a catalyst bed
temperature of 800°C (±10°C) at steady-state stoichiometric operation.
The air injection system is set to provide the necessary air flow to produce 3.0% oxygen (±0.1%) in
the steady-state stoichiometric exhaust stream just in front of the first catalyst. A typical reading at
the upstream A/F measurement point (required in Paragraph 3.4 of this Annex) is lambda 1.16
(which is approximately 3 % oxygen).
With the air injection on, set the 'Rich' A/F ratio to produce a catalyst bed temperature
of 890°C (±10°C). A typical A/F value for this step is lambda 0.94 (approximately 2% CO).
3.7. Ageing cycle. The standard bench ageing procedures use the Standard Bench Cycle (SBC). The
SBC is repeated until the amount of ageing calculated from the Bench Ageing Time (BAT)
equation is achieved.
3.8. Quality assurance. The temperatures and A/F ratio in Paragraph 3.3. and 3.4. shall be reviewed
periodically (at least every 50h) during ageing. Necessary adjustments shall be made to assure
that the SBC is being appropriately followed throughout the ageing process.
After the ageing has been completed, the catalyst time-at-temperature collected during the ageing
process shall be tabulated into a histogram with temperature groups of no larger than 10°C.
The BAT equation and the calculated effective reference temperature for the ageing cycle in
accordance with Paragraph 2.4. of Annex 3 will be used to determine if the appropriate amount of
thermal ageing of the catalyst has in fact occurred. Bench ageing will be extended if the thermal
effect of the calculated ageing time is not at least 95% of the target thermal ageing.
3.9. Startup and shutdown. Care should be taken to assure that the maximum catalyst temperature for
rapid deterioration (e.g., 1,050°C) does not occur during startup or shutdown. Special low
temperature startup and shutdown procedures may be used to alleviate this concern.
4.7. Compare the R-factor to the initial value that was used in accordance with Paragraph 4.3. If the
calculated R-factor differs from the initial value by more than 5%, choose a new R-factor that is
between the initial and calculated values, and then repeat steps of Paragraph 4 to derive a new
R-factor. Repeat this process until the calculated R-factor is within 5% of the initially assumed
4.8. Compare the R-factor determined separately for each exhaust constituent. Use the lowest R-factor
(worst case) for the BAT equation.
Determining the R-factor
TESTS OF A REPLACEMENT POLLUTION-CONTROL DEVICE
1. SCOPE OF THE ANNEX
This Annex applies to the pollution-control devices to be fitted as replacement parts on one or
more types of vehicle in the scope of this GTR.
2.1. Requirements Regarding Pollutant Tailpipe Emissions
2.1.1. The manufacturer of the replacement pollution-control device shall prepare a vehicle(s) of
a type certified in accordance with Amendment 5 to UN GTR No. 2 equipped with a new
original equipment pollution-control device. This (these) vehicles shall be selected by the
applicant with the agreement of the authority. It (they) shall comply with the requirements of the
Type I test set out in Annex 1 of Amendment 5 to UN GTR No. 2.
The vehicle referred to in Paragraph 3.2.1., equipped with a replacement pollution-control
device is requested, shall undergo the tests laid down in Annex 1 and 2 (depending on the
certification of the vehicle) of Amendment 5 to UN GTR No. 2 and either Annex 1, Annex 2,
Annex 3 or Annex 4 of this GTR.
220.127.116.11. Evaluation of Pollutant Tailpipe Emissions from Vehicles Equipped with Replacement
Requirements regarding tailpipe are deemed to be complied with if the test vehicle equipped
with the replacement pollutant-control device complies with the limit values in Amendment 5 to
UN GTR No. 2.