Amendments to UN Regulation No 168 – Uniform provisions concerning the approval of light duty passenger and commercial vehicles with regards to real driving emissions (RDE) [2026/1900]
Date: 2026-06-15
Institutions: United Nations Economic Commission for Europe
Subjects: approval, child, motor vehicle, safety device, safety standard, technical specification, technical standard




L_202601900EN.000101.fmx.xml












Official Journal of the European Union


EN
L series













2026/1900


15.6.2026





Only the original UN/ECE texts have legal effect under international public law. The status and date of entry into force of this Regulation should be checked in the latest version of the UN/ECE status document TRANS/WP.29/343, available at: https://unece.org/status-1958-agreement-and-annexed-regulations


Amendments to UN Regulation No 168 – Uniform provisions concerning the approval of light duty passenger and commercial vehicles with regards to real driving emissions (RDE) [2026/1900]

Amendments to Regulation 168 published in Official Journal 2024/211 of 12 January 2024
      

Incorporating:

Supplement 1 to the original version of the Regulation - Date of entry into force: 26 September 2025
         
01 series of amendments - Date of entry into force: September 2026 (TBC)
This document is meant purely as documentation tool. The authentic and legally binding texts are:
ECE/TRANS/WP.29/2025/29
ECE/TRANS/WP.29/2026/27

Paragraph 1., amend to read:






"1.


Scope and application
This Regulation aims at providing a worldwide harmonized method to determine the levels of Real Driving Emissions (RDE) of gaseous compounds and particles from light-duty vehicles.
This Regulation provides requirements for three levels of approval. The first level requires testing and evaluation based on a 4-phase WLTC (low, medium, high and extra-high) – this is called Level 1A. The second level requires testing and evaluation based on a 3-phase WLTC cycle (low, medium and high) – this is called Level 1B. The third level requires testing and evaluation based on both a 4-phase WLTC and a 3-phase WLTC cycle – this is called Level 2.
Level 2 shall be considered to be the “highest level of stringency” in the context of paragraph 2 of Article 1 of the 1958 Agreement.
Where the requirements in this Regulation apply to either Level 1A, Level 1B or Level 2 only, the Regulatory text refers to the relevant level to denote the start of the level specific requirements.
Pure Electric Vehicles and Fuel Cell Vehicles are out of the scope of this Regulation.










1.1.


Scope for Level 1A;
This Regulation applies to the type approval of vehicles of categories M1 and N1 with regard to their Real Driving Emissions.
At the request of the manufacturer, for vehicles of category N2 between 3.5 and 5 tonnes maximum mass originating from a type of vehicle of category N1, the approval authority may grant an emission type-approval if the vehicle meets the requirements for a type of vehicle of category N1.










1.2.


Scope for Level 1B;
This Regulation applies to the type approval of vehicles of categories M2 and N1 with a technical permissible maximum laden mass not exceeding 3 500 kg and to all vehicles of category M1 with regard to their Real Driving Emissions.










1.3.


Scope for Level 2;
This Regulation applies to the type approval of vehicles of categories M1 and N1 with regard to their Real Driving Emissions."





Paragraph 3.1., amend to read:







"3.1.


Administrative"






Insert new paragraphs 3.1.1. to 3.1.3., to read:







"3.1.1.



"Vehicle type with regard to Real Driving Emissions" means a group of vehicles which do not differ with respect to the criteria constituting a "PEMS test family" as defined in paragraph 6.3.1. or, if applicable, paragraph 6.3.2.










3.1.2.



"Declared Maximum RDE" means the emission values, which shall necessarily be lower than the applicable emission limits, declared optionally by the manufacturer and used for checking compliance against lower emission limits.










3.1.3.



"Third party" means a party with legitimate interest and the resources to testing facilities with accreditation in accordance with EN ISO/IEC 17020 and EN ISO/IEC 17025."






Paragraph 3.3.5., amend to read:







"3.3.5.


Reserved"






Insert a new paragraph 4.5., to read:







"4.5.


For Level 1A only:
For vehicle types with an existing valid type-approval issued in accordance with the Original Version of this Regulation and for which a manufacturer requests a type-approval with regards to Real Driving Emissions in accordance with Series of Amendments 01, new type-approval testing shall not be required if:






(a)


the manufacturer declares to the granting type-approval authority that compliance with the requirements of Series of Amendments 01 is ensured; and










(b)


the technical service responsible for the testing agrees that the previous type-approved test results can be used for the preparation of a new emission test report to demonstrate compliance to the requirements of Series of Amendments 01."










Paragraph 5.2.1., amend to read:







"5.2.1.


The type approval number shall consist of four sections. Each section shall be separated by the '*' character.







Section 1


:


The capital letter 'E' followed by the distinguishing number of the Contracting Party which has granted the type approval.




Section 2


:


The number of this UN Regulation, followed by the letter 'R', successively followed by:






(a)


Two digits (with leading zeros as applicable) indicating the series of amendments incorporating the technical provisions of the UN Regulation applied to the approval (00 for the UN Regulation in its original form);










(b)


A slash (/) and two digits (with leading zeros as applicable) indicating the number of supplements to the series of amendments applied to the approval (00 for the series of amendments in its original form);










(c)


A slash (/) and two character(s) indicating the implementing stage/level (e.g. 1A, 1B or 2).








Section 3


:


A four-digit sequential number (with leading zeros as applicable). The sequence shall start from 0001.




Section 4


:


A two-digit sequential number (with leading zeros if applicable) to denote the extension. The sequence shall start from 00.




All digits shall be Arabic digits."






Paragraph 5.2.2., amend to read:







"5.2.2.


Example of an Approval Number to this Regulation:
E11*168R01/02/1A*0123*01
The first extension of the Approval numbered 0123, issued by the United Kingdom to Supplement 2 to Series of Amendments 01, which is a Level 1A Approval."






Insert a new paragraph 5.4.3., to read:







"5.4.3.


The approval mark shall contain an additional code after the type approval number, the purpose of which is to distinguish the level (Level 1A, 1B or 2) for which the approval has been granted. This code should be chosen according to the Table A3/1 of Annex 3 to this Regulation."






Paragraph 6.1., amend to read:







"6.1.


Compliance requirements
For vehicle types approved according to Level 1A of this Regulation, the final emissions at any possible RDE test performed in accordance with the requirements of this Regulation, shall be calculated for evaluation with a 4-phase WLTC.
For vehicle types approved according to Level 1B of this Regulation, the final emissions at any possible RDE test performed for vehicles with a diesel engine in accordance with the requirements of this Regulation, shall be calculated for evaluation with a 3-phase WLTC.
For vehicle types approved according to Level 2 of this Regulation, the final emissions at any possible RDE test performed in accordance with the requirements of this Regulation, shall be calculated for evaluation with a 4-phase WLTC and for vehicles with a diesel engine additionally with a 3-phase WLTC.






Requirements for evaluation with 4 Phase WLTC


Requirements for evaluation with 3 Phase WLTC




The final emissions for the 4-phase analysis shall not be higher than any of the limits for the relevant criteria emissions (i.e. NOX and PN) found in Table 1A of paragraph 6.3.10. of the 04 series of Amendments to UN Regulation No. 154 on WLTP.


The final emissions for the 3-phase analysis shall not be higher than the NOX limits found in Table 1B of paragraph 6.3.10. of the 04 series of Amendments to UN Regulation No. 154 on WLTP.




The requirements of emission limits shall be fulfilled for the urban operation and the complete PEMS trip.
The manufacturer may declare for Level 1A and Level 2 in the case of 4-phase WLTC evaluation compliance with lower emission limits by declaring lower values called ‘Declared Maximum RDE’, either for NOx or PN or both, in the Manufacturer’s RDE certificate of compliance found in Annex 12 of this Regulation. These Declared Maximum RDE values shall be used for checking the compliance of cars when applicable.
The RDE tests required by this Regulation provide a presumption of conformity. The presumed conformity may be reassessed by additional RDE tests.
The manufacturer shall ensure that all vehicles within the PEMS test family are compliant with UN Regulation No. 154 on WLTP, including conformity of production requirements.
The RDE performance shall be demonstrated by performing the necessary tests in the PEMS test family on the road, operated over their normal driving patterns, conditions and payloads. The necessary tests shall be representative for vehicles operated on their real driving routes, with their normal load."






Paragraph 6.4.1.2., amend to read:







"6.4.1.2.


The authority shall select additional vehicles according to the requirements of paragraph 6.4.3. for PEMS testing carried out by a Technical Service to demonstrate compliance of the selected vehicles with the requirements of this Regulation. The technical criteria for selection of an additional vehicle according to paragraph 6.4.3. shall be recorded with the test results."






Paragraph 6.4.1.3., amend to read:







"6.4.1.3.


With agreement of the authority, a PEMS test can also be driven by a different operator witnessed by a Technical Service, provided that at least the tests of the vehicles required by paragraphs 6.4.3.2. and 6.4.3.6. and in total at least 50 per cent of the PEMS tests required by paragraph 6.4.3.7. for validating the PEMS test family are driven by a Technical Service. In such case the Technical Service remains responsible for the proper execution of all PEMS tests pursuant to the requirements of this Regulation."






Paragraph 8.3.1., amend to read:







"8.3.1.


Vehicle condition
The vehicle, including the emission related components, shall be in good mechanical condition and shall have been run in and driven at least 3 000 km before the test. The mileage and the age of the vehicle used for RDE testing shall be recorded.
All vehicles, and in particular OVC-HEVs may be tested in any selectable mode, including battery charge mode. On the basis of technical evidence provided by the manufacturer and with the agreement of the responsible authority, the dedicated driver-selectable modes for very special limited purposes shall not be considered (e.g. maintenance mode, race driving, crawler mode). All remaining modes used for forward and for rearwards driving where road and traffic conditions demand this may be considered and the criteria emissions limits shall be fulfilled in all these modes.
Modifications that affect the vehicle aerodynamics are not permitted, with the exception of the PEMS installation. The tyre types and pressure shall be according to the vehicle's manufacturer recommendations. The tyre pressure shall be checked prior to the pre-conditioning and adjusted to the recommended values if needed. Driving the vehicle with snow chains is not permitted.
Vehicles should not be tested with an empty starter battery. In case the vehicle has problems starting, the battery shall be replaced following the recommendations of the vehicle's manufacturer.
The vehicle's test mass comprises of the driver, a witness of the test (if applicable), the test equipment, including the mounting and the power supply devices and any artificial payload. It shall be between the actual mass of the vehicle and the maximum permissible test mass of the vehicle at the beginning of the test and shall not increase during the test.
The test vehicles shall not be driven with the intention to generate a passed or failed test due to extreme driving that do not represent normal conditions of use. If necessary, verification of normal driving may be based on expert judgement made by or on behalf of the granting type approval authority through cross-correlation on several signals, which may include exhaust flow rate, exhaust temperature, CO2, O2 etc. in combination with vehicle speed, acceleration and GNSS data and potentially further vehicle data parameters like engine speed, gear, accelerator pedal position etc."






Paragraph 9.2., amend to read:







"9.2.


Required distance shares of trip speed bins
The following is the distribution of the speed bins in an RDE trip that are required for respecting the needs of evaluation for both the 4-phase WLTC and where applicable the 3-phase WLTC:






Requirements for evaluation with 4-Phase WLTC


Requirements for evaluation with 3-Phase WLTC




The trip shall consist of approximately 34 per cent urban, 33 per cent rural and 33 per cent motorway speed bins. ‘Approximately’ shall mean the interval of ±10 per cent points around the stated percentages. The urban speed bin shall however never be less than 29 per cent of the total trip distance.


The trip shall consist of approximately 55 per cent urban and 45 per cent expressway speed bins. ‘Approximately’ shall mean the interval of ±10 per cent points around the stated percentages. The urban speed bin however can be lower than 45 per cent but never be less than 40 per cent of the total trip distance.




The shares of urban, rural and motorway speed bins shall be expressed as a percentage of the total trip distance for analysis with 4-Phase WLTC.
Where applicable, the shares of urban and expressway speed bins shall be expressed as a percentage of the trip distance with speed not exceeding 100 km/h for analysis with 3-Phase WLTC.
The minimum distance of each, urban, rural and motorway or expressway speed bins shall be 16 km."






Paragraph 9.3., amend to read:







"9.3.


RDE test to be performed
The RDE performance shall be demonstrated by testing vehicles on the road, operated over their normal driving patterns, conditions and payloads. RDE tests shall be conducted on paved roads (e.g. off-road operation is not permitted). Either a single RDE trip or two dedicated RDE trips shall be driven in order to prove compliance with the associated emission requirements, i.e.:






(a)


For Level 1A Approvals against a 4-Phase WLTC










(b)


For Level 1B Approvals against a 3-Phase WLTC










(c)


For Level 2 Approvals against both 3-Phase WLTC and 4-Phase WLTC"










Paragraph 10.7., amend to read:







"10.7.


Where applicable, separate data-sets shall be created for 3-phase and 4-phase evaluation. For Level 2 Approvals the data collected during the entire trip shall be the basis of the 4-phase RDE emission results, while the data with the exclusion of any data point with speed above 100 km/h shall be the basis of the 3-phase RDE trip validity and emission results calculations according to paragraphs 8 and 9 and Annexes 8, 9 and 11. For data analysis continuity Annex 10 will begin with the entire data set for both analyses."






Paragraph 10.7.1., amend to read:







"10.7.1.


For vehicles with a diesel engine, in the case that a single RDE trip for a Level 2 Approval is not capable of complying with all validity requirements described in paragraphs 9.1.1., 9.2. and 9.3., paragraphs 4.5.1. and 4.5.2. of Annex 8 and paragraph 4. of Annex 9 simultaneously, then a second RDE trip shall be done. The second trip shall be designed to meet either the 3-phase or 4-phase WLTC trip requirements not yet satisfied, as well as all other relevant trip validity requirements, but it is not necessary to satisfy again the 4-phase or 3-phase WLTC trip requirements previously met by the first trip."






Paragraph 10.7.2., amend to read:







"10.7.2.


For vehicles with a diesel engine, in case the emission calculated for the 3-phase RDE trip exceed the emission limits for the total trip due to the exclusion of all data points with speed above 100 km/h even though the trip is compliant, then a second trip with the speed limited to less than or equal to 100 km/h shall be made and evaluated for compliance with the 3-phase requirements"’






Paragraph 10.8., amend to read:







"10.8.


Data Reporting: For Level 1A and Level 2 in the case of 4-phase WLTC evaluation only, all data of a single RDE test shall be recorded according to the data exchange and data reporting files found in the same weblink as this Regulation3.
A test report shall be prepared by the Technical Service in accordance with the Data Reporting File and shall be made available to the Contracting Party."






Insert new paragraphs 10.9. to 10.9.2.2., to read:







"10.9.


Reporting and dissemination of RDE type-approval test information for Level 1A and Level 2 in the case of 4-phase WLTC evaluation only.










10.9.1.


A technical report prepared by the manufacturer shall be made available to the approval authority. The technical report is composed of 4 items:






(i)


the Data Exchange file










(ii)


the Reporting file










(iii)


the Vehicle and engine description as described in Annex 2 of this Regulation;










(iv)


visual supporting material (photographs and/or videos) of the PEMS installation in the tested vehicle of adequate quality and quantity to identify the vehicle and to assess if the installation of the PEMS main unit, the EFM, the GNSS antenna, and the weather station follow the instrument manufacturers recommendations and the general good practices of PEMS testing.














10.9.2.


The manufacturer shall ensure that the information listed in paragraph 10.9.2.1. is made available on a publicly accessible website without costs and without the need for the user to reveal his identity or sign up. The manufacturer shall keep the granting Type Approval Authority and upon request Contracting Parties informed on the location of the website.










10.9.2.1.


The website shall allow a wildcard search of the underlying database based on one or more of the following (as applicable):
Make, Type, Variant, Version, Commercial name, or Type Approval Number.
The information described below shall be made available for each vehicle in a search:






—


The PEMS family ID to which that vehicle belongs, in accordance with the Transparency List 2 of Appendix 5 of Annex 4 to UN Regulation No. 83;










—


If applicable, the Declared Maximum RDE Values in accordance with this UN Regulation.














10.9.2.2.


Upon request, without costs and within 10 days, the manufacturer shall make available the technical report referred to in paragraph 10.9.1. to any Contracting Party or recognised third party. The manufacturer shall also make available the technical report referred to in paragraph 10.9.1. upon request and with a reasonable and proportionate fee to others, which does not discourage an inquirer with a justified interest from requesting the respective information or exceed the internal costs of the manufacturer for making the requested information available.
Upon request, the type-approval authority shall make available the information listed under paragraphs 10.9.1. and 10.9.2. without costs and within 10 days of receiving the request to any Contracting Party or recognised third party. The type-approval authority shall also make available to others upon request the information listed under paragraphs 10.9.1. and 10.9.2. with a reasonable and proportionate fee, which does not discourage an inquirer with a justified interest from requesting the respective information or exceed the internal costs of the authority for making the requested information available."






Paragraph 15, amend to read:







"15.


Transitional and Special provisions"





Include a new paragraph 15.2. to read:







"15.2.


Provisions for special purpose vehicles










15.2.1.


Provisions for armoured vehicles
For Level 1A only:
The responsible authority may grant type-approvals including exemption(s) to requirements of this regulation to armoured vehicles in accordance with point 2.5.2. of the Consolidated Resolution on the Construction of Vehicles (R.E.3), if the manufacturer demonstrates that the vehicle cannot meet the requirements due to its special purpose.
The type of special purpose vehicle and the exemptions granted are to be described in point 1.0. of section I of the type-approval certificate in accordance with Annex 2 to this regulation."






Annex 1, text of Part 1, amend to read:






"Part 1


In the case that all vehicles included in the approval to this Regulation are also approved to UN Regulation No. 154:






 


Approval number(s) to UN Regulation No. 154 or Interpolation family identifier(s): ….."









Annex 1, Item 0.2.2.1. of Part 1 and Part 2, amend to read:







"0.2.2.1.


Allowed Parameter Values for multistage type approval (if applicable) to use the base vehicle emission values (insert range if applicable):
Final Vehicle actual mass (in kg):
Final Vehicle technically permissible maximum laden mass (in kg):
Frontal area for final vehicle (in cm2):
Rolling resistance (kg/t):
Cross-sectional area of air entrance of the front grille (in cm2):"






Annex 2, amend to read:

"…
of a vehicle type with regard to Real Driving Emissions pursuant to UN Regulation No. 168
…"


Annex 3, amend to read:

"Arrangement of the approval mark
In the approval mark issued and affixed to a vehicle in conformity with paragraph 5. of this Regulation, the type approval number shall be accompanied by an alphanumeric character reflecting the level that the approval is limited to.
This annex outlines the appearance of this mark and gives an example how it shall be composed.
The following schematic graphic presents the general lay-out, proportions and contents of the marking. The meaning of numbers and alphabetical character are identified, and sources to determine the corresponding alternatives for each approval case are also referred.





a = 8 mm (minimum)
The following graphic is a practical example of how the marking should be composed.





The preceding approval mark affixed to a vehicle in conformity with paragraph 5. of this Regulation shows that the vehicle type concerned has been approved in the United Kingdom (E 11), pursuant to UN Regulation No. 168 under approval number 2439, as defined in Section 3 of paragraph 5.2.1. This mark indicates that the approval was given in accordance with the requirements of this Regulation with the 01 series of amendments incorporated. Furthermore, the accompanying code (1A) denotes that the vehicle is approved to Level 1A (Europe).

Table A3/1


Characters with reference to approval level







Code


Contracting Party on which the requirements are based




1A


European Union




1B


Japan




2


Harmonized"






Annex 4, Paragraph 6.1., amend to read:







"6.1.


Checking the analysers for measuring gaseous emissions
The zero and span of the analysers of gaseous components shall be checked by using calibration gases identical to the ones applied under paragraph 4.5. to evaluate the analyser's zero and response drift compared to the pre-test calibration. It is permissible to zero the analyser prior to verifying the span drift, if the zero drift was determined to be within the permissible range. The post-test drift check shall be completed as soon as possible after the test and before the PEMS, or individual analysers or sensors, are turned off or have switched into a non-operating mode. The difference between the pre-test and post-test results shall comply with the requirements specified in Table A4/2.

Table A4/2


Permissible analyser drift over a PEMS test








Pollutant


Absolute Zero response drift


Absolute Span response drift (1)





CO2



≤ 2 000  ppm per test


≤ 2 % of reading or ≤ 2 000  ppm per test, whichever is larger




CO


≤ 75 ppm per test


≤ 2 % of reading or ≤ 75 ppm per test, whichever is larger




NOX



≤ 3 ppm per test


≤ 2 % of reading or ≤ 3 ppm per test, whichever is larger




CH4



≤ 10 ppm C1 per test


≤ 2 % of reading or ≤ 10 ppm C1 per test, whichever is larger




THC


≤ 10 ppm C1 per test


≤ 2 % of reading or ≤ 10 ppm C1 per test, whichever is larger





(1)  If the zero drift is within the permissible range, it is permissible to zero the analyser prior to verifying the span drift.




If the difference between the pre-test and post-test results for the zero and span drift is higher than permitted, all test results shall be invalid and the test repeated.
At the request of the manufacturer and with approval of the approval authority, the permissible drifts may be exceeded if:






(i)


the difference between the uncorrected and the corrected concentration values according to paragraph 5.0. of Annex 7 are lower than 6 per cent of the uncorrected concentration values, and










(ii)


the uncorrected and the corrected emissions values give the same conclusion as to whether or not there is an exceedance of the emissions limits."










Annex 5, paragraph 6.1., amend to read:







"6.1.


General
The PN analyser shall consist of a pre-conditioning unit and a particle detector that counts with minimum 50 per cent efficiency from approximately 10 nm. It is permissible that the particle detector also pre-conditions the aerosol. The sensitivity of the analysers to shocks, vibration, aging, variability in temperature and air pressure as well as electromagnetic interferences and other impacts related to vehicle and analyser operation shall be limited as far as possible and shall be clearly stated by the equipment manufacturer in its support material. The PN analyser shall only be used within its manufacturer’s declared parameters of operation. An example of a PN analyser setup is provided in Figure A5/1.
The PN analyser shall be connected to the sampling point via a sampling probe which extracts a sample from the centreline of the tailpipe tube. As specified in paragraph 3.5. of Annex 4, if particles are not diluted at the tailpipe, the sampling line shall be heated to a minimum temperature of 373 K (100 °C) until the point of first dilution of the PN analyser or the particle detector of the analyser. The residence time in the sampling line shall be less than 3 s.
All parts in contact with the sampled exhaust gas shall be always kept at a temperature that avoids condensation of any compound in the device. This can be achieved for example by heating at a higher temperature and diluting the sample or oxidizing the (semi)volatile species.
The PN analyser shall include a catalytically active heated section at wall temperature ≥ 573 K. The unit shall control the heated stages to constant nominal operating temperatures, within a tolerance of ± 10 K, and provide an indication of whether or not heated stages are at their correct operating temperatures. Lower temperatures are acceptable as long as the volatile particle removal efficiency fulfils the specifications of paragraph 6.4.
Pressure, temperature and other sensors shall monitor the proper operation of the instrument during operation and trigger a warning or message in case of malfunction.
The delay time of the PN analyser shall be ≤ 5 s.
The PN analyser (and/or particle detector) shall have a rise time of ≤ 3.5 s.
Particle concentration measurements shall be reported normalised to 273 K and 101.3 kPa. If necessary, the pressure and/or temperature at the inlet of the detector shall be measured and reported for the purposes of normalizing the particle concentration.
PN systems that comply with the calibration requirements of UN Regulation Nos 83 or 49 or UN Regulation No. 154 on WLTP automatically comply with the calibration requirements of this annex."






Annex 5, heading of figure A5/1, amend to read:

"Example of a PN analyser setup: Dotted lines depict optional parts. The heated section shall be catalytically active. EFM = Exhaust mass Flow Meter, d = inner diameter, PND = Particle Number Diluter."


Annex 5, Table A5/3a, is replaced with the following:

"Table A5/3a


PN analyser (including the sampling line) system efficiency requirements













dp [nm]


10


15


30


50


70


100


200




E(dp) PN analyser


0.1 – 0.5


0.3 – 0.7


0.75 – 1.05


0.85 – 1.15


0.85 – 1.15


0.8 – 1.2


0.8 – 2.0"






Annex 5, paragraph 6.2., amend to read:







"6.2.


Efficiency requirements
The complete PN analyser system including the sampling line shall fulfil the efficiency requirements of Table A5/3a.
Efficiency E(dp) is defined as the ratio in the readings of the PN analyser system to a reference Condensation Particle Counter (CPC)’s (with counting efficiency above 90 per cent for 10 nm equivalent electrical mobility diameter, checked for linearity and calibrated with an electrometer) or an Electrometer’s number concentration measuring in parallel monodisperse aerosol of mobility diameter dp and normalized at the same temperature and pressure conditions.
The material should be thermally stable soot-like (e.g. spark discharged graphite or diffusion flame soot with thermal pre-treatment). If the efficiency curve is measured with a different aerosol (e.g. NaCl), the correlation to the soot-like curve must be provided as a chart which compares the efficiencies obtained using both test aerosols. The differences in the counting efficiencies shall be taken into account by adjusting the measured efficiencies based on the provided chart to give soot-like aerosol efficiencies. The correction for multiply charged particles shall be applied and documented but shall not exceed 10 per cent. These efficiencies refer to the PN analysers with the sampling line. The PN analyser can also be calibrated in parts (i.e. the pre-conditioning unit separately from the particle detector) as long as it is proven that the PN analyser and the sampling line together fulfil the requirements of Table A5/3a. The measured signal from the detector shall be > 2 times the limit of detection (here defined as the zero level plus 3 standard deviations)."






Annex 5, paragraph 6.3., amend to read:







"6.3.


Linearity requirements
The PN analyser including the sampling line shall fulfil the linearity requirements of paragraph 3.2. of Annex 5 using monodisperse or polydisperse soot-like particles. The particle size (mobility diameter or count median diameter) shall be larger than 45 nm. The reference instrument shall be an Electrometer or a Condensation Particle Counter (CPC) with counting efficiency above 90 per cent for 10 nm equivalent electrical mobility diameter, verified for linearity. Alternatively, a particle number system compliant with UN Regulation No. 154 on WLTP with a counting efficiency above 90 per cent for 10 nm equivalent electrical mobility diameter can be used as reference instrument for the linearity check of the complete system.
In addition, the differences of the PN analyser from the reference instrument at all points checked (except the zero point) shall be within 15 per cent of their mean value. At least 5 points equally distributed (plus the zero) shall be checked. The maximum checked concentration shall be > 90 per cent of the PN analyser nominal measurement range.
If the PN analyser is calibrated in parts, then the linearity can be checked only for the PN detector, but the efficiencies of the rest parts and the sampling line shall be considered in the slope calculation."






Annex 5, paragraph 6.4., amend to read:







"6.4.


Volatile removal efficiency
The system shall achieve > 99.9 per cent removal of ≥ 30 nm tetracontane (CH3(CH2)38CH3) particles with an inlet concentration of ≥ 10 000 particles per cubic-centimetre at the minimum dilution.
The system shall also achieve a > 99.9 per cent removal efficiency of tetracontane with count median diameter > 50 nm and mass > 1 mg/m3.
The volatile removal efficiency with tetracontane shall be proven only once for the instrument family. The instrument manufacturer though shall provide the maintenance or replacement interval that ensures that the removal efficiency does not drop below the technical requirements. If such information is not provided, the volatile removal efficiency shall be checked yearly for each instrument."






Annex 8, paragraph 1., amend to read:







"1.


Introduction
The Moving Averaging Window method shall be used to assess the overall trip dynamics. The test is divided in sub-sections (windows) and the subsequent analysis aims at determining whether the trip is valid for RDE purposes. The ‘normality’ of the windows shall be assessed by comparing their CO2 distance-specific emissions with a reference curve obtained from the vehicle CO2 emissions measured in accordance with the WLTP test.
For compliance with this Regulation, the method shall be applied using the 4-phase and where applicable the 3-phase WLTC requirements."






Annex 8, paragraph 4.4.1.2., amend to read:







"4.4.1.2.


Medium speed windows
Medium speed windows are characterized by average vehicle ground speeds

greater than or equal to 45 km/h and lower than 80 km/h.
For those vehicles that are equipped with a device limiting vehicle speed to 90 km/h, medium-speed windows are characterized by average vehicle speeds

lower than 70 km/h."






Annex 8, paragraph 4.4.1.3., amend to read:







"4.4.1.3.


High speed windows
High speed windows are characterized by average vehicle ground speeds

greater than or equal to 80 km/h and lower than 145 km/h
For those vehicles that are equipped with a device limiting vehicle speed to 90 km/h, high-speed windows are characterized by average vehicle speeds

greater than or equal to 70 km/h and lower than 90 km/h."






Annex 8, title of Figure A8/5, amend to read:

"Vehicle CO2 characteristic curve: low, medium and high speed definitions (Illustrated for ICE and NOVC-HEV) except those vehicles that are equipped with a device limiting vehicle speed to 90 km/h"


Annex 8, title of Figure A8/6, amend to read:

"Vehicle CO2 characteristic curve: low, medium and high speed definitions (Illustrated for OVC-HEV) except those vehicles that are equipped with a device limiting vehicle speed to 90 km/h"


Annex 9, paragraph 3.1.3.1., amend to read:







"3.1.3.1.


Binning of the results (for analysis with 4-phase WLTP)
After the calculation of ai and (v × a)
i
, the values vi, di, ai and (v × a)
i
 shall be ranked in ascending order of the vehicle speed.
All datasets with (vi
≤ 60 km/h) belong to the ‘urban’ speed bin, all datasets with (60 km/h < vi
 ≤ 90 km/h) belong to the ‘rural’ speed bin and all datasets with (vi
 > 90 km/h) belong to the ‘motorway’ speed bin.
For those vehicles that are equipped with a device limiting vehicle speed to 90 km/h, all datasets with

≤ 60 km/h belong to the “urban” speed bin, all datasets with 60 km/h <

≤ 80 km/h belong to the “rural” speed bin and all datasets with

> 80 km/h belong to the “motorway” speed bin.
The number of datasets with acceleration valuesai > 0.1 m/s2 shall be greater than or equal to 100 in each speed bin.
…"






Annex 10, paragraph 4.3.3., amend to read:







"4.3.3.


Calculation of the final result
The positive cumulative elevation gain of a total trip shall be calculated by integrating all positive interpolated and smoothed road grades, i.e., roadgrade,2(d). The result should be normalized by the total test distance d
tot and expressed in meters of cumulative elevation gain per one hundred kilometres of distance.
The waypoint vehicle speed vw shall then be calculated over each discrete way point of 1m:





Where applicable for 3-phase WLTP evaluation all datasets with vw ≤ 100 km/h are used for the calculation of the cumulative positive altitude gain of the complete trip.
All of the positive …"






Annex 11, paragraph 1., amend to read:







"1.


Introduction
This annex describes the procedure to calculate the final criteria emissions for the complete and urban part of an RDE trip for the 4-phase and where applicable the 3-phase WLTP."






Annex 11, paragraph 3., amend to read:







"3.


Calculation of the Intermediate RDE emissions results
…



and



The RDE result evaluation factors

(k=t=total, k=u=urban) shall be obtained using the functions laid down in paragraph 3.1. for vehicles with ICE and NOVC-HEV, and in paragraph 3.2. for OVC-HEV. A graphical illustration of the method is provided in Figure A11/1 below, while the mathematical formulas are found in Table A11/1:
…"






Annex 12, insert a second bullet point to read:
"…

Annex:







—


List of vehicle types to which this certificate applies










—


List of the Declared Maximum RDE values for each vehicle type expressed as mg/km or particle numbers/km as appropriate."






ELI: http://data.europa.eu/eli/reg/2026/1900/oj
ISSN 1977-0677 (electronic edition)