Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter and particle number emissions from Heavy-Duty Vehicles. The UN GTR defines the test cycle (Worldwide Harmonized Heavy Duty Brake Cycle), minimum system requirements, test conditions, equipment preparation, brake dynamometer capabilities, brake enclosure design, sampling tunnel design, and sampling plane design. It applies to vehicles of categories M₂, M₃, N₂, N₃, and O₃, O₄ concerning braking, covering both friction braking systems (disc and drum brakes). The regulation includes requirements for brake bedding procedures, emissions measurements, calibration, and ongoing quality controls. A version with tracked changes is available.

Proposal to establish a new supplement to UN Regulation No. 179, improving and correcting brake emissions measurement procedures for light-duty vehicles of categories M₁ and N₁. The regulation applies full-friction braking testing on brake dynamometers using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. Testing includes three sections: cooling air adjustment, brake bedding with five cycle repetitions, and emissions measurement with three cycle repetitions. Compliance is demonstrated by measuring PM10 and SPN10 emissions from brake corner emission family parents, with whole-vehicle emissions calculated using friction braking share coefficients specific to vehicle electrification types. PM10 limits are 3 mg/km for M₁/N₁ vehicles and 5 mg/km for N₁ Class III/N₂ vehicles. Conformity of production requires annual testing of brake corner emission families with statistical evaluation per decision charts through 31 December 2029 (Phase I, PM10 only), with Phase II from 1 January 2030 evaluating both PM10 and SPN10. A version of this document with tracked changes is available.

Proposal to modify UN GTR No. 24 with respect to laboratory measurement procedures for brake emissions of light-duty vehicles. This amendment improves and corrects the testing procedure, including detailed requirements for test system setup, cooling air conditioning, brake dynamometer specifications, WLTP-Brake cycle execution, emissions measurements for particulate matter (PM2.5, PM10) and particle number (TPN10, SPN10), calibration protocols, and reporting of results. The regulation defines brake corner emissions families, friction braking share coefficients for different vehicle electrification types (ICE, HEV categories, PEV), and test procedures using fully-enclosed brake dynamometers with isokinetic sampling systems. A version with tracked changes is available.

Proposal to include testing of vehicles with limited speed. The document sets out the laboratory measurement procedure for brake emissions from light-duty vehicles of categories M₁ and N₁, including vehicles with maximum speed below the Base cycle maximum speed. Testing involves three sections: cooling air adjustment, brake bedding with five repetitions of the WLTP-Brake cycle, and brake emissions measurement with one WLTP-Brake cycle. Brake corner emission families are tested on a component test bench under full-friction braking conditions, measuring PM₁₀ and SPN₁₀ emissions. Compliance is demonstrated using brake corner emissions family parents. Conformity of production requires monthly sampling and testing of brake components, with results evaluated using statistical decision charts through 31 December 2029 for PM₁₀ and thereafter for both PM₁₀ and SPN₁₀.

Proposal to establish a new UN Regulation transposing UN GTR No. 24 into uniform provisions concerning approval of non-original and identical replacement brake parts (brake pads, drum brake linings, brake discs, and brake drums) with regards to particle emissions. The regulation applies to vehicles of category M₁, N₁, and N₂ between 3.5 and 5 tonnes maximum mass. Replacement brake parts must comply with particle emission limits, with emission factors calculated using test wheel load and friction braking share coefficient for the brake emissions family parent. Approval marks must be affixed to approved parts, and conformity of production shall be verified through sampling and testing procedures.

Proposal to amend and enhance the procedure for laboratory measurement of brake emissions for light-duty vehicles. The document provides comprehensive technical specifications covering scope and application for vehicles of categories M₁ and N₁, detailed abbreviations and symbols for measurement parameters, definitions of vehicle types and brake systems, application and approval procedures, conformity of production requirements with statistical evaluation procedures, and penalty provisions for non-conformity. Testing procedures include three sections: cooling air adjustment, brake bedding, and brake emissions measurement, all executed using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. CoP verification shall be performed once every 12 months with samples from each brake corner emission family, evaluated according to decision charts specified in the regulation.

Proposal to amend UN Regulation No. 179 to include testing of vehicles with limited speed. The document specifies amendments to the laboratory measurement of brake emissions for light-duty vehicles, including provisions for vehicles with a maximum speed lower than the maximum speed of the Base cycle. These vehicles may be part of the same brake corner emissions family as vehicles suitable for the Base cycle, with their emission factor calculated based on the parent family’s reference PM and PN emissions according to equations 7.1, 7.2 and 7.3. At the manufacturer’s request and with approval authority agreement, such limited-speed vehicles may be assigned to a specific family using the adjusted cycle described in Appendix 3 of Annex 4, with the same changes to be applied to UN GTR No. 24.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter (PM) and particle number (PN) emissions from heavy-duty vehicles, including trucks and buses, using a Worldwide Harmonized Heavy Duty Vehicles Brake Cycle (WHBC) and brake dynamometer testing. The GTR specifies test system requirements, including brake enclosure design, sampling tunnel specifications, climatic conditioning with cooling air temperature maintained at 23°C±2°C and relative humidity at 50%±5%, cooling airflow at 2500 Nm/h±5%, test preparation procedures, brake bedding with six repetitions of the WHBC followed by emissions measurement during one WHBC cycle, requirements for PM10, PM2.5, TPN10, and SPN10 measurement systems, brake temperature measurement using embedded thermocouples, calibration and validation procedures, and reporting of emission factors. The regulation applies to vehicles of categories M₂, M₃, N₂, N₃ [and O₃, O₄] with friction braking systems.

Final status report on development of a new UN GTR for laboratory measurement of brake particle matter (PM) and particle number (PN) emissions from heavy-duty vehicles. The GTR introduces brake emissions groups based on fundamental design and performance characteristics, defines brake group nominal test parameters by disc or drum diameter, establishes friction braking share coefficients with c-factor = 1 for full-friction braking, specifies required test input parameters including brake system type and filtering systems, prescribes the Worldwide Harmonized Heavy-Duty Brake Cycle (WHBC) comprising 246 brake events over 5:39 hours across urban, rural, and motorway segments, defines PM and PN measurement methodologies using gravimetrical and particle number counter methods, specifies hardware requirements including brake dynamometer, enclosure dimensions of 1950 mm length × 1000 mm height × 700 mm depth with divider plate, sampling tunnel with 300 mm fixed inner diameter, and brake temperature measurement by embedded thermocouples, and includes results of preliminary interlaboratory study.

Proposal to amend UN GTR No. 24 by modifying test procedures, definitions, and requirements for brake particle emissions measurement. The amendment introduces improvements including revised definitions (vehicle electrification type, material formulation, pad size), updated measurement tolerances and signal filtering requirements, provisions for brake filtering systems, enhanced specifications for drum and electromechanical brake systems, relaxed cooling airflow adjustment requirements, and a new test cycle for speed-limited vehicles. Documentation of calibration requirements and ongoing quality controls are clarified throughout.

The document authorizes development of a new UN GTR on brake PM and PN emissions from all types of light-duty vehicle brake systems, including validation of the developed novel WLTP-Brake test cycle, investigation and selection of instrumentation and sampling methodology for brake wear particles, definition of minimum requirements for sampling, validation through interlaboratory study, inclusion of regenerative braking, and preparation of the PMP Brake protocol. It also reports on Amendment 2 to UN GTR No. 24 covering laboratory measurement of brake emissions for light-duty vehicles, detailing hardware requirements, test cycle specifications, cooling air conditioning, bedding procedures, and emissions measurement methodologies for particulate matter and particle number.

Proposal to amend Annex 2 – Appendix 1 to add para. 1.4.1. specifying user-selectable mode(s) resulting in the lowest recuperation and relevant pre-test procedures for vehicles with a vehicle specific c-factor according to Annex 5, and to delete items not brake emission related including brake circuit configuration, secondary braking system declaration, brake valve specifications, master cylinder type and size, and booster type and size.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter and particle number emissions from Heavy-Duty Vehicles. The UN GTR defines the test cycle (Worldwide Harmonized Heavy Duty Brake Cycle), minimum system requirements, test conditions, equipment preparation, brake dynamometer capabilities, brake enclosure design, sampling tunnel design, and sampling plane design. It applies to vehicles of categories M₂, M₃, N₂, N₃, and O₃, O₄ concerning braking, covering both friction braking systems (disc and drum brakes). The regulation includes requirements for brake bedding procedures, emissions measurements, calibration, and ongoing quality controls. A version with tracked changes is available.

Proposal to establish a new supplement to UN Regulation No. 179, improving and correcting brake emissions measurement procedures for light-duty vehicles of categories M₁ and N₁. The regulation applies full-friction braking testing on brake dynamometers using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. Testing includes three sections: cooling air adjustment, brake bedding with five cycle repetitions, and emissions measurement with three cycle repetitions. Compliance is demonstrated by measuring PM10 and SPN10 emissions from brake corner emission family parents, with whole-vehicle emissions calculated using friction braking share coefficients specific to vehicle electrification types. PM10 limits are 3 mg/km for M₁/N₁ vehicles and 5 mg/km for N₁ Class III/N₂ vehicles. Conformity of production requires annual testing of brake corner emission families with statistical evaluation per decision charts through 31 December 2029 (Phase I, PM10 only), with Phase II from 1 January 2030 evaluating both PM10 and SPN10. A version of this document with tracked changes is available.

Proposal to modify UN GTR No. 24 with respect to laboratory measurement procedures for brake emissions of light-duty vehicles. This amendment improves and corrects the testing procedure, including detailed requirements for test system setup, cooling air conditioning, brake dynamometer specifications, WLTP-Brake cycle execution, emissions measurements for particulate matter (PM2.5, PM10) and particle number (TPN10, SPN10), calibration protocols, and reporting of results. The regulation defines brake corner emissions families, friction braking share coefficients for different vehicle electrification types (ICE, HEV categories, PEV), and test procedures using fully-enclosed brake dynamometers with isokinetic sampling systems. A version with tracked changes is available.

Proposal to include testing of vehicles with limited speed. The document sets out the laboratory measurement procedure for brake emissions from light-duty vehicles of categories M₁ and N₁, including vehicles with maximum speed below the Base cycle maximum speed. Testing involves three sections: cooling air adjustment, brake bedding with five repetitions of the WLTP-Brake cycle, and brake emissions measurement with one WLTP-Brake cycle. Brake corner emission families are tested on a component test bench under full-friction braking conditions, measuring PM₁₀ and SPN₁₀ emissions. Compliance is demonstrated using brake corner emissions family parents. Conformity of production requires monthly sampling and testing of brake components, with results evaluated using statistical decision charts through 31 December 2029 for PM₁₀ and thereafter for both PM₁₀ and SPN₁₀.

Proposal to establish a new UN Regulation transposing UN GTR No. 24 into uniform provisions concerning approval of non-original and identical replacement brake parts (brake pads, drum brake linings, brake discs, and brake drums) with regards to particle emissions. The regulation applies to vehicles of category M₁, N₁, and N₂ between 3.5 and 5 tonnes maximum mass. Replacement brake parts must comply with particle emission limits, with emission factors calculated using test wheel load and friction braking share coefficient for the brake emissions family parent. Approval marks must be affixed to approved parts, and conformity of production shall be verified through sampling and testing procedures.

Proposal to amend and enhance the procedure for laboratory measurement of brake emissions for light-duty vehicles. The document provides comprehensive technical specifications covering scope and application for vehicles of categories M₁ and N₁, detailed abbreviations and symbols for measurement parameters, definitions of vehicle types and brake systems, application and approval procedures, conformity of production requirements with statistical evaluation procedures, and penalty provisions for non-conformity. Testing procedures include three sections: cooling air adjustment, brake bedding, and brake emissions measurement, all executed using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. CoP verification shall be performed once every 12 months with samples from each brake corner emission family, evaluated according to decision charts specified in the regulation.

Proposal to amend UN Regulation No. 179 to include testing of vehicles with limited speed. The document specifies amendments to the laboratory measurement of brake emissions for light-duty vehicles, including provisions for vehicles with a maximum speed lower than the maximum speed of the Base cycle. These vehicles may be part of the same brake corner emissions family as vehicles suitable for the Base cycle, with their emission factor calculated based on the parent family’s reference PM and PN emissions according to equations 7.1, 7.2 and 7.3. At the manufacturer’s request and with approval authority agreement, such limited-speed vehicles may be assigned to a specific family using the adjusted cycle described in Appendix 3 of Annex 4, with the same changes to be applied to UN GTR No. 24.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter (PM) and particle number (PN) emissions from heavy-duty vehicles, including trucks and buses, using a Worldwide Harmonized Heavy Duty Vehicles Brake Cycle (WHBC) and brake dynamometer testing. The GTR specifies test system requirements, including brake enclosure design, sampling tunnel specifications, climatic conditioning with cooling air temperature maintained at 23°C±2°C and relative humidity at 50%±5%, cooling airflow at 2500 Nm/h±5%, test preparation procedures, brake bedding with six repetitions of the WHBC followed by emissions measurement during one WHBC cycle, requirements for PM10, PM2.5, TPN10, and SPN10 measurement systems, brake temperature measurement using embedded thermocouples, calibration and validation procedures, and reporting of emission factors. The regulation applies to vehicles of categories M₂, M₃, N₂, N₃ [and O₃, O₄] with friction braking systems.

Final status report on development of a new UN GTR for laboratory measurement of brake particle matter (PM) and particle number (PN) emissions from heavy-duty vehicles. The GTR introduces brake emissions groups based on fundamental design and performance characteristics, defines brake group nominal test parameters by disc or drum diameter, establishes friction braking share coefficients with c-factor = 1 for full-friction braking, specifies required test input parameters including brake system type and filtering systems, prescribes the Worldwide Harmonized Heavy-Duty Brake Cycle (WHBC) comprising 246 brake events over 5:39 hours across urban, rural, and motorway segments, defines PM and PN measurement methodologies using gravimetrical and particle number counter methods, specifies hardware requirements including brake dynamometer, enclosure dimensions of 1950 mm length × 1000 mm height × 700 mm depth with divider plate, sampling tunnel with 300 mm fixed inner diameter, and brake temperature measurement by embedded thermocouples, and includes results of preliminary interlaboratory study.

Proposal to amend UN GTR No. 24 by modifying test procedures, definitions, and requirements for brake particle emissions measurement. The amendment introduces improvements including revised definitions (vehicle electrification type, material formulation, pad size), updated measurement tolerances and signal filtering requirements, provisions for brake filtering systems, enhanced specifications for drum and electromechanical brake systems, relaxed cooling airflow adjustment requirements, and a new test cycle for speed-limited vehicles. Documentation of calibration requirements and ongoing quality controls are clarified throughout.

The document authorizes development of a new UN GTR on brake PM and PN emissions from all types of light-duty vehicle brake systems, including validation of the developed novel WLTP-Brake test cycle, investigation and selection of instrumentation and sampling methodology for brake wear particles, definition of minimum requirements for sampling, validation through interlaboratory study, inclusion of regenerative braking, and preparation of the PMP Brake protocol. It also reports on Amendment 2 to UN GTR No. 24 covering laboratory measurement of brake emissions for light-duty vehicles, detailing hardware requirements, test cycle specifications, cooling air conditioning, bedding procedures, and emissions measurement methodologies for particulate matter and particle number.

Proposal to amend Annex 2 – Appendix 1 to add para. 1.4.1. specifying user-selectable mode(s) resulting in the lowest recuperation and relevant pre-test procedures for vehicles with a vehicle specific c-factor according to Annex 5, and to delete items not brake emission related including brake circuit configuration, secondary braking system declaration, brake valve specifications, master cylinder type and size, and booster type and size.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter and particle number emissions from Heavy-Duty Vehicles. The UN GTR defines the test cycle (Worldwide Harmonized Heavy Duty Brake Cycle), minimum system requirements, test conditions, equipment preparation, brake dynamometer capabilities, brake enclosure design, sampling tunnel design, and sampling plane design. It applies to vehicles of categories M₂, M₃, N₂, N₃, and O₃, O₄ concerning braking, covering both friction braking systems (disc and drum brakes). The regulation includes requirements for brake bedding procedures, emissions measurements, calibration, and ongoing quality controls. A version with tracked changes is available.

Proposal to establish a new supplement to UN Regulation No. 179, improving and correcting brake emissions measurement procedures for light-duty vehicles of categories M₁ and N₁. The regulation applies full-friction braking testing on brake dynamometers using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. Testing includes three sections: cooling air adjustment, brake bedding with five cycle repetitions, and emissions measurement with three cycle repetitions. Compliance is demonstrated by measuring PM10 and SPN10 emissions from brake corner emission family parents, with whole-vehicle emissions calculated using friction braking share coefficients specific to vehicle electrification types. PM10 limits are 3 mg/km for M₁/N₁ vehicles and 5 mg/km for N₁ Class III/N₂ vehicles. Conformity of production requires annual testing of brake corner emission families with statistical evaluation per decision charts through 31 December 2029 (Phase I, PM10 only), with Phase II from 1 January 2030 evaluating both PM10 and SPN10. A version of this document with tracked changes is available.

Proposal to modify UN GTR No. 24 with respect to laboratory measurement procedures for brake emissions of light-duty vehicles. This amendment improves and corrects the testing procedure, including detailed requirements for test system setup, cooling air conditioning, brake dynamometer specifications, WLTP-Brake cycle execution, emissions measurements for particulate matter (PM2.5, PM10) and particle number (TPN10, SPN10), calibration protocols, and reporting of results. The regulation defines brake corner emissions families, friction braking share coefficients for different vehicle electrification types (ICE, HEV categories, PEV), and test procedures using fully-enclosed brake dynamometers with isokinetic sampling systems. A version with tracked changes is available.

Proposal to include testing of vehicles with limited speed. The document sets out the laboratory measurement procedure for brake emissions from light-duty vehicles of categories M₁ and N₁, including vehicles with maximum speed below the Base cycle maximum speed. Testing involves three sections: cooling air adjustment, brake bedding with five repetitions of the WLTP-Brake cycle, and brake emissions measurement with one WLTP-Brake cycle. Brake corner emission families are tested on a component test bench under full-friction braking conditions, measuring PM₁₀ and SPN₁₀ emissions. Compliance is demonstrated using brake corner emissions family parents. Conformity of production requires monthly sampling and testing of brake components, with results evaluated using statistical decision charts through 31 December 2029 for PM₁₀ and thereafter for both PM₁₀ and SPN₁₀.

Proposal to establish a new UN Regulation transposing UN GTR No. 24 into uniform provisions concerning approval of non-original and identical replacement brake parts (brake pads, drum brake linings, brake discs, and brake drums) with regards to particle emissions. The regulation applies to vehicles of category M₁, N₁, and N₂ between 3.5 and 5 tonnes maximum mass. Replacement brake parts must comply with particle emission limits, with emission factors calculated using test wheel load and friction braking share coefficient for the brake emissions family parent. Approval marks must be affixed to approved parts, and conformity of production shall be verified through sampling and testing procedures.

Proposal to amend and enhance the procedure for laboratory measurement of brake emissions for light-duty vehicles. The document provides comprehensive technical specifications covering scope and application for vehicles of categories M₁ and N₁, detailed abbreviations and symbols for measurement parameters, definitions of vehicle types and brake systems, application and approval procedures, conformity of production requirements with statistical evaluation procedures, and penalty provisions for non-conformity. Testing procedures include three sections: cooling air adjustment, brake bedding, and brake emissions measurement, all executed using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. CoP verification shall be performed once every 12 months with samples from each brake corner emission family, evaluated according to decision charts specified in the regulation.

Proposal to amend UN Regulation No. 179 to include testing of vehicles with limited speed. The document specifies amendments to the laboratory measurement of brake emissions for light-duty vehicles, including provisions for vehicles with a maximum speed lower than the maximum speed of the Base cycle. These vehicles may be part of the same brake corner emissions family as vehicles suitable for the Base cycle, with their emission factor calculated based on the parent family’s reference PM and PN emissions according to equations 7.1, 7.2 and 7.3. At the manufacturer’s request and with approval authority agreement, such limited-speed vehicles may be assigned to a specific family using the adjusted cycle described in Appendix 3 of Annex 4, with the same changes to be applied to UN GTR No. 24.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter (PM) and particle number (PN) emissions from heavy-duty vehicles, including trucks and buses, using a Worldwide Harmonized Heavy Duty Vehicles Brake Cycle (WHBC) and brake dynamometer testing. The GTR specifies test system requirements, including brake enclosure design, sampling tunnel specifications, climatic conditioning with cooling air temperature maintained at 23°C±2°C and relative humidity at 50%±5%, cooling airflow at 2500 Nm/h±5%, test preparation procedures, brake bedding with six repetitions of the WHBC followed by emissions measurement during one WHBC cycle, requirements for PM10, PM2.5, TPN10, and SPN10 measurement systems, brake temperature measurement using embedded thermocouples, calibration and validation procedures, and reporting of emission factors. The regulation applies to vehicles of categories M₂, M₃, N₂, N₃ [and O₃, O₄] with friction braking systems.

Final status report on development of a new UN GTR for laboratory measurement of brake particle matter (PM) and particle number (PN) emissions from heavy-duty vehicles. The GTR introduces brake emissions groups based on fundamental design and performance characteristics, defines brake group nominal test parameters by disc or drum diameter, establishes friction braking share coefficients with c-factor = 1 for full-friction braking, specifies required test input parameters including brake system type and filtering systems, prescribes the Worldwide Harmonized Heavy-Duty Brake Cycle (WHBC) comprising 246 brake events over 5:39 hours across urban, rural, and motorway segments, defines PM and PN measurement methodologies using gravimetrical and particle number counter methods, specifies hardware requirements including brake dynamometer, enclosure dimensions of 1950 mm length × 1000 mm height × 700 mm depth with divider plate, sampling tunnel with 300 mm fixed inner diameter, and brake temperature measurement by embedded thermocouples, and includes results of preliminary interlaboratory study.

Proposal to amend UN GTR No. 24 by modifying test procedures, definitions, and requirements for brake particle emissions measurement. The amendment introduces improvements including revised definitions (vehicle electrification type, material formulation, pad size), updated measurement tolerances and signal filtering requirements, provisions for brake filtering systems, enhanced specifications for drum and electromechanical brake systems, relaxed cooling airflow adjustment requirements, and a new test cycle for speed-limited vehicles. Documentation of calibration requirements and ongoing quality controls are clarified throughout.

The document authorizes development of a new UN GTR on brake PM and PN emissions from all types of light-duty vehicle brake systems, including validation of the developed novel WLTP-Brake test cycle, investigation and selection of instrumentation and sampling methodology for brake wear particles, definition of minimum requirements for sampling, validation through interlaboratory study, inclusion of regenerative braking, and preparation of the PMP Brake protocol. It also reports on Amendment 2 to UN GTR No. 24 covering laboratory measurement of brake emissions for light-duty vehicles, detailing hardware requirements, test cycle specifications, cooling air conditioning, bedding procedures, and emissions measurement methodologies for particulate matter and particle number.

Proposal to amend Annex 2 – Appendix 1 to add para. 1.4.1. specifying user-selectable mode(s) resulting in the lowest recuperation and relevant pre-test procedures for vehicles with a vehicle specific c-factor according to Annex 5, and to delete items not brake emission related including brake circuit configuration, secondary braking system declaration, brake valve specifications, master cylinder type and size, and booster type and size.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter and particle number emissions from Heavy-Duty Vehicles. The UN GTR defines the test cycle (Worldwide Harmonized Heavy Duty Brake Cycle), minimum system requirements, test conditions, equipment preparation, brake dynamometer capabilities, brake enclosure design, sampling tunnel design, and sampling plane design. It applies to vehicles of categories M₂, M₃, N₂, N₃, and O₃, O₄ concerning braking, covering both friction braking systems (disc and drum brakes). The regulation includes requirements for brake bedding procedures, emissions measurements, calibration, and ongoing quality controls. A version with tracked changes is available.

Proposal to establish a new supplement to UN Regulation No. 179, improving and correcting brake emissions measurement procedures for light-duty vehicles of categories M₁ and N₁. The regulation applies full-friction braking testing on brake dynamometers using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. Testing includes three sections: cooling air adjustment, brake bedding with five cycle repetitions, and emissions measurement with three cycle repetitions. Compliance is demonstrated by measuring PM10 and SPN10 emissions from brake corner emission family parents, with whole-vehicle emissions calculated using friction braking share coefficients specific to vehicle electrification types. PM10 limits are 3 mg/km for M₁/N₁ vehicles and 5 mg/km for N₁ Class III/N₂ vehicles. Conformity of production requires annual testing of brake corner emission families with statistical evaluation per decision charts through 31 December 2029 (Phase I, PM10 only), with Phase II from 1 January 2030 evaluating both PM10 and SPN10. A version of this document with tracked changes is available.

Proposal to modify UN GTR No. 24 with respect to laboratory measurement procedures for brake emissions of light-duty vehicles. This amendment improves and corrects the testing procedure, including detailed requirements for test system setup, cooling air conditioning, brake dynamometer specifications, WLTP-Brake cycle execution, emissions measurements for particulate matter (PM2.5, PM10) and particle number (TPN10, SPN10), calibration protocols, and reporting of results. The regulation defines brake corner emissions families, friction braking share coefficients for different vehicle electrification types (ICE, HEV categories, PEV), and test procedures using fully-enclosed brake dynamometers with isokinetic sampling systems. A version with tracked changes is available.

Proposal to include testing of vehicles with limited speed. The document sets out the laboratory measurement procedure for brake emissions from light-duty vehicles of categories M₁ and N₁, including vehicles with maximum speed below the Base cycle maximum speed. Testing involves three sections: cooling air adjustment, brake bedding with five repetitions of the WLTP-Brake cycle, and brake emissions measurement with one WLTP-Brake cycle. Brake corner emission families are tested on a component test bench under full-friction braking conditions, measuring PM₁₀ and SPN₁₀ emissions. Compliance is demonstrated using brake corner emissions family parents. Conformity of production requires monthly sampling and testing of brake components, with results evaluated using statistical decision charts through 31 December 2029 for PM₁₀ and thereafter for both PM₁₀ and SPN₁₀.

Proposal to establish a new UN Regulation transposing UN GTR No. 24 into uniform provisions concerning approval of non-original and identical replacement brake parts (brake pads, drum brake linings, brake discs, and brake drums) with regards to particle emissions. The regulation applies to vehicles of category M₁, N₁, and N₂ between 3.5 and 5 tonnes maximum mass. Replacement brake parts must comply with particle emission limits, with emission factors calculated using test wheel load and friction braking share coefficient for the brake emissions family parent. Approval marks must be affixed to approved parts, and conformity of production shall be verified through sampling and testing procedures.

Proposal to amend and enhance the procedure for laboratory measurement of brake emissions for light-duty vehicles. The document provides comprehensive technical specifications covering scope and application for vehicles of categories M₁ and N₁, detailed abbreviations and symbols for measurement parameters, definitions of vehicle types and brake systems, application and approval procedures, conformity of production requirements with statistical evaluation procedures, and penalty provisions for non-conformity. Testing procedures include three sections: cooling air adjustment, brake bedding, and brake emissions measurement, all executed using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. CoP verification shall be performed once every 12 months with samples from each brake corner emission family, evaluated according to decision charts specified in the regulation.

Proposal to amend UN Regulation No. 179 to include testing of vehicles with limited speed. The document specifies amendments to the laboratory measurement of brake emissions for light-duty vehicles, including provisions for vehicles with a maximum speed lower than the maximum speed of the Base cycle. These vehicles may be part of the same brake corner emissions family as vehicles suitable for the Base cycle, with their emission factor calculated based on the parent family’s reference PM and PN emissions according to equations 7.1, 7.2 and 7.3. At the manufacturer’s request and with approval authority agreement, such limited-speed vehicles may be assigned to a specific family using the adjusted cycle described in Appendix 3 of Annex 4, with the same changes to be applied to UN GTR No. 24.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter (PM) and particle number (PN) emissions from heavy-duty vehicles, including trucks and buses, using a Worldwide Harmonized Heavy Duty Vehicles Brake Cycle (WHBC) and brake dynamometer testing. The GTR specifies test system requirements, including brake enclosure design, sampling tunnel specifications, climatic conditioning with cooling air temperature maintained at 23°C±2°C and relative humidity at 50%±5%, cooling airflow at 2500 Nm/h±5%, test preparation procedures, brake bedding with six repetitions of the WHBC followed by emissions measurement during one WHBC cycle, requirements for PM10, PM2.5, TPN10, and SPN10 measurement systems, brake temperature measurement using embedded thermocouples, calibration and validation procedures, and reporting of emission factors. The regulation applies to vehicles of categories M₂, M₃, N₂, N₃ [and O₃, O₄] with friction braking systems.

Final status report on development of a new UN GTR for laboratory measurement of brake particle matter (PM) and particle number (PN) emissions from heavy-duty vehicles. The GTR introduces brake emissions groups based on fundamental design and performance characteristics, defines brake group nominal test parameters by disc or drum diameter, establishes friction braking share coefficients with c-factor = 1 for full-friction braking, specifies required test input parameters including brake system type and filtering systems, prescribes the Worldwide Harmonized Heavy-Duty Brake Cycle (WHBC) comprising 246 brake events over 5:39 hours across urban, rural, and motorway segments, defines PM and PN measurement methodologies using gravimetrical and particle number counter methods, specifies hardware requirements including brake dynamometer, enclosure dimensions of 1950 mm length × 1000 mm height × 700 mm depth with divider plate, sampling tunnel with 300 mm fixed inner diameter, and brake temperature measurement by embedded thermocouples, and includes results of preliminary interlaboratory study.

Proposal to amend UN GTR No. 24 by modifying test procedures, definitions, and requirements for brake particle emissions measurement. The amendment introduces improvements including revised definitions (vehicle electrification type, material formulation, pad size), updated measurement tolerances and signal filtering requirements, provisions for brake filtering systems, enhanced specifications for drum and electromechanical brake systems, relaxed cooling airflow adjustment requirements, and a new test cycle for speed-limited vehicles. Documentation of calibration requirements and ongoing quality controls are clarified throughout.

The document authorizes development of a new UN GTR on brake PM and PN emissions from all types of light-duty vehicle brake systems, including validation of the developed novel WLTP-Brake test cycle, investigation and selection of instrumentation and sampling methodology for brake wear particles, definition of minimum requirements for sampling, validation through interlaboratory study, inclusion of regenerative braking, and preparation of the PMP Brake protocol. It also reports on Amendment 2 to UN GTR No. 24 covering laboratory measurement of brake emissions for light-duty vehicles, detailing hardware requirements, test cycle specifications, cooling air conditioning, bedding procedures, and emissions measurement methodologies for particulate matter and particle number.

Proposal to amend Annex 2 – Appendix 1 to add para. 1.4.1. specifying user-selectable mode(s) resulting in the lowest recuperation and relevant pre-test procedures for vehicles with a vehicle specific c-factor according to Annex 5, and to delete items not brake emission related including brake circuit configuration, secondary braking system declaration, brake valve specifications, master cylinder type and size, and booster type and size.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter and particle number emissions from Heavy-Duty Vehicles. The UN GTR defines the test cycle (Worldwide Harmonized Heavy Duty Brake Cycle), minimum system requirements, test conditions, equipment preparation, brake dynamometer capabilities, brake enclosure design, sampling tunnel design, and sampling plane design. It applies to vehicles of categories M₂, M₃, N₂, N₃, and O₃, O₄ concerning braking, covering both friction braking systems (disc and drum brakes). The regulation includes requirements for brake bedding procedures, emissions measurements, calibration, and ongoing quality controls. A version with tracked changes is available.

Proposal to establish a new supplement to UN Regulation No. 179, improving and correcting brake emissions measurement procedures for light-duty vehicles of categories M₁ and N₁. The regulation applies full-friction braking testing on brake dynamometers using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. Testing includes three sections: cooling air adjustment, brake bedding with five cycle repetitions, and emissions measurement with three cycle repetitions. Compliance is demonstrated by measuring PM10 and SPN10 emissions from brake corner emission family parents, with whole-vehicle emissions calculated using friction braking share coefficients specific to vehicle electrification types. PM10 limits are 3 mg/km for M₁/N₁ vehicles and 5 mg/km for N₁ Class III/N₂ vehicles. Conformity of production requires annual testing of brake corner emission families with statistical evaluation per decision charts through 31 December 2029 (Phase I, PM10 only), with Phase II from 1 January 2030 evaluating both PM10 and SPN10. A version of this document with tracked changes is available.

Proposal to modify UN GTR No. 24 with respect to laboratory measurement procedures for brake emissions of light-duty vehicles. This amendment improves and corrects the testing procedure, including detailed requirements for test system setup, cooling air conditioning, brake dynamometer specifications, WLTP-Brake cycle execution, emissions measurements for particulate matter (PM2.5, PM10) and particle number (TPN10, SPN10), calibration protocols, and reporting of results. The regulation defines brake corner emissions families, friction braking share coefficients for different vehicle electrification types (ICE, HEV categories, PEV), and test procedures using fully-enclosed brake dynamometers with isokinetic sampling systems. A version with tracked changes is available.

Proposal to include testing of vehicles with limited speed. The document sets out the laboratory measurement procedure for brake emissions from light-duty vehicles of categories M₁ and N₁, including vehicles with maximum speed below the Base cycle maximum speed. Testing involves three sections: cooling air adjustment, brake bedding with five repetitions of the WLTP-Brake cycle, and brake emissions measurement with one WLTP-Brake cycle. Brake corner emission families are tested on a component test bench under full-friction braking conditions, measuring PM₁₀ and SPN₁₀ emissions. Compliance is demonstrated using brake corner emissions family parents. Conformity of production requires monthly sampling and testing of brake components, with results evaluated using statistical decision charts through 31 December 2029 for PM₁₀ and thereafter for both PM₁₀ and SPN₁₀.

Proposal to establish a new UN Regulation transposing UN GTR No. 24 into uniform provisions concerning approval of non-original and identical replacement brake parts (brake pads, drum brake linings, brake discs, and brake drums) with regards to particle emissions. The regulation applies to vehicles of category M₁, N₁, and N₂ between 3.5 and 5 tonnes maximum mass. Replacement brake parts must comply with particle emission limits, with emission factors calculated using test wheel load and friction braking share coefficient for the brake emissions family parent. Approval marks must be affixed to approved parts, and conformity of production shall be verified through sampling and testing procedures.

Proposal to amend and enhance the procedure for laboratory measurement of brake emissions for light-duty vehicles. The document provides comprehensive technical specifications covering scope and application for vehicles of categories M₁ and N₁, detailed abbreviations and symbols for measurement parameters, definitions of vehicle types and brake systems, application and approval procedures, conformity of production requirements with statistical evaluation procedures, and penalty provisions for non-conformity. Testing procedures include three sections: cooling air adjustment, brake bedding, and brake emissions measurement, all executed using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. CoP verification shall be performed once every 12 months with samples from each brake corner emission family, evaluated according to decision charts specified in the regulation.

Proposal to amend UN Regulation No. 179 to include testing of vehicles with limited speed. The document specifies amendments to the laboratory measurement of brake emissions for light-duty vehicles, including provisions for vehicles with a maximum speed lower than the maximum speed of the Base cycle. These vehicles may be part of the same brake corner emissions family as vehicles suitable for the Base cycle, with their emission factor calculated based on the parent family’s reference PM and PN emissions according to equations 7.1, 7.2 and 7.3. At the manufacturer’s request and with approval authority agreement, such limited-speed vehicles may be assigned to a specific family using the adjusted cycle described in Appendix 3 of Annex 4, with the same changes to be applied to UN GTR No. 24.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter (PM) and particle number (PN) emissions from heavy-duty vehicles, including trucks and buses, using a Worldwide Harmonized Heavy Duty Vehicles Brake Cycle (WHBC) and brake dynamometer testing. The GTR specifies test system requirements, including brake enclosure design, sampling tunnel specifications, climatic conditioning with cooling air temperature maintained at 23°C±2°C and relative humidity at 50%±5%, cooling airflow at 2500 Nm/h±5%, test preparation procedures, brake bedding with six repetitions of the WHBC followed by emissions measurement during one WHBC cycle, requirements for PM10, PM2.5, TPN10, and SPN10 measurement systems, brake temperature measurement using embedded thermocouples, calibration and validation procedures, and reporting of emission factors. The regulation applies to vehicles of categories M₂, M₃, N₂, N₃ [and O₃, O₄] with friction braking systems.

Final status report on development of a new UN GTR for laboratory measurement of brake particle matter (PM) and particle number (PN) emissions from heavy-duty vehicles. The GTR introduces brake emissions groups based on fundamental design and performance characteristics, defines brake group nominal test parameters by disc or drum diameter, establishes friction braking share coefficients with c-factor = 1 for full-friction braking, specifies required test input parameters including brake system type and filtering systems, prescribes the Worldwide Harmonized Heavy-Duty Brake Cycle (WHBC) comprising 246 brake events over 5:39 hours across urban, rural, and motorway segments, defines PM and PN measurement methodologies using gravimetrical and particle number counter methods, specifies hardware requirements including brake dynamometer, enclosure dimensions of 1950 mm length × 1000 mm height × 700 mm depth with divider plate, sampling tunnel with 300 mm fixed inner diameter, and brake temperature measurement by embedded thermocouples, and includes results of preliminary interlaboratory study.

Proposal to amend UN GTR No. 24 by modifying test procedures, definitions, and requirements for brake particle emissions measurement. The amendment introduces improvements including revised definitions (vehicle electrification type, material formulation, pad size), updated measurement tolerances and signal filtering requirements, provisions for brake filtering systems, enhanced specifications for drum and electromechanical brake systems, relaxed cooling airflow adjustment requirements, and a new test cycle for speed-limited vehicles. Documentation of calibration requirements and ongoing quality controls are clarified throughout.

The document authorizes development of a new UN GTR on brake PM and PN emissions from all types of light-duty vehicle brake systems, including validation of the developed novel WLTP-Brake test cycle, investigation and selection of instrumentation and sampling methodology for brake wear particles, definition of minimum requirements for sampling, validation through interlaboratory study, inclusion of regenerative braking, and preparation of the PMP Brake protocol. It also reports on Amendment 2 to UN GTR No. 24 covering laboratory measurement of brake emissions for light-duty vehicles, detailing hardware requirements, test cycle specifications, cooling air conditioning, bedding procedures, and emissions measurement methodologies for particulate matter and particle number.

Proposal to amend Annex 2 – Appendix 1 to add para. 1.4.1. specifying user-selectable mode(s) resulting in the lowest recuperation and relevant pre-test procedures for vehicles with a vehicle specific c-factor according to Annex 5, and to delete items not brake emission related including brake circuit configuration, secondary braking system declaration, brake valve specifications, master cylinder type and size, and booster type and size.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter and particle number emissions from Heavy-Duty Vehicles. The UN GTR defines the test cycle (Worldwide Harmonized Heavy Duty Brake Cycle), minimum system requirements, test conditions, equipment preparation, brake dynamometer capabilities, brake enclosure design, sampling tunnel design, and sampling plane design. It applies to vehicles of categories M₂, M₃, N₂, N₃, and O₃, O₄ concerning braking, covering both friction braking systems (disc and drum brakes). The regulation includes requirements for brake bedding procedures, emissions measurements, calibration, and ongoing quality controls. A version with tracked changes is available.

Proposal to establish a new supplement to UN Regulation No. 179, improving and correcting brake emissions measurement procedures for light-duty vehicles of categories M₁ and N₁. The regulation applies full-friction braking testing on brake dynamometers using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. Testing includes three sections: cooling air adjustment, brake bedding with five cycle repetitions, and emissions measurement with three cycle repetitions. Compliance is demonstrated by measuring PM10 and SPN10 emissions from brake corner emission family parents, with whole-vehicle emissions calculated using friction braking share coefficients specific to vehicle electrification types. PM10 limits are 3 mg/km for M₁/N₁ vehicles and 5 mg/km for N₁ Class III/N₂ vehicles. Conformity of production requires annual testing of brake corner emission families with statistical evaluation per decision charts through 31 December 2029 (Phase I, PM10 only), with Phase II from 1 January 2030 evaluating both PM10 and SPN10. A version of this document with tracked changes is available.

Proposal to modify UN GTR No. 24 with respect to laboratory measurement procedures for brake emissions of light-duty vehicles. This amendment improves and corrects the testing procedure, including detailed requirements for test system setup, cooling air conditioning, brake dynamometer specifications, WLTP-Brake cycle execution, emissions measurements for particulate matter (PM2.5, PM10) and particle number (TPN10, SPN10), calibration protocols, and reporting of results. The regulation defines brake corner emissions families, friction braking share coefficients for different vehicle electrification types (ICE, HEV categories, PEV), and test procedures using fully-enclosed brake dynamometers with isokinetic sampling systems. A version with tracked changes is available.

Proposal to include testing of vehicles with limited speed. The document sets out the laboratory measurement procedure for brake emissions from light-duty vehicles of categories M₁ and N₁, including vehicles with maximum speed below the Base cycle maximum speed. Testing involves three sections: cooling air adjustment, brake bedding with five repetitions of the WLTP-Brake cycle, and brake emissions measurement with one WLTP-Brake cycle. Brake corner emission families are tested on a component test bench under full-friction braking conditions, measuring PM₁₀ and SPN₁₀ emissions. Compliance is demonstrated using brake corner emissions family parents. Conformity of production requires monthly sampling and testing of brake components, with results evaluated using statistical decision charts through 31 December 2029 for PM₁₀ and thereafter for both PM₁₀ and SPN₁₀.

Proposal to establish a new UN Regulation transposing UN GTR No. 24 into uniform provisions concerning approval of non-original and identical replacement brake parts (brake pads, drum brake linings, brake discs, and brake drums) with regards to particle emissions. The regulation applies to vehicles of category M₁, N₁, and N₂ between 3.5 and 5 tonnes maximum mass. Replacement brake parts must comply with particle emission limits, with emission factors calculated using test wheel load and friction braking share coefficient for the brake emissions family parent. Approval marks must be affixed to approved parts, and conformity of production shall be verified through sampling and testing procedures.

Proposal to amend and enhance the procedure for laboratory measurement of brake emissions for light-duty vehicles. The document provides comprehensive technical specifications covering scope and application for vehicles of categories M₁ and N₁, detailed abbreviations and symbols for measurement parameters, definitions of vehicle types and brake systems, application and approval procedures, conformity of production requirements with statistical evaluation procedures, and penalty provisions for non-conformity. Testing procedures include three sections: cooling air adjustment, brake bedding, and brake emissions measurement, all executed using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. CoP verification shall be performed once every 12 months with samples from each brake corner emission family, evaluated according to decision charts specified in the regulation.

Proposal to amend UN Regulation No. 179 to include testing of vehicles with limited speed. The document specifies amendments to the laboratory measurement of brake emissions for light-duty vehicles, including provisions for vehicles with a maximum speed lower than the maximum speed of the Base cycle. These vehicles may be part of the same brake corner emissions family as vehicles suitable for the Base cycle, with their emission factor calculated based on the parent family’s reference PM and PN emissions according to equations 7.1, 7.2 and 7.3. At the manufacturer’s request and with approval authority agreement, such limited-speed vehicles may be assigned to a specific family using the adjusted cycle described in Appendix 3 of Annex 4, with the same changes to be applied to UN GTR No. 24.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter (PM) and particle number (PN) emissions from heavy-duty vehicles, including trucks and buses, using a Worldwide Harmonized Heavy Duty Vehicles Brake Cycle (WHBC) and brake dynamometer testing. The GTR specifies test system requirements, including brake enclosure design, sampling tunnel specifications, climatic conditioning with cooling air temperature maintained at 23°C±2°C and relative humidity at 50%±5%, cooling airflow at 2500 Nm/h±5%, test preparation procedures, brake bedding with six repetitions of the WHBC followed by emissions measurement during one WHBC cycle, requirements for PM10, PM2.5, TPN10, and SPN10 measurement systems, brake temperature measurement using embedded thermocouples, calibration and validation procedures, and reporting of emission factors. The regulation applies to vehicles of categories M₂, M₃, N₂, N₃ [and O₃, O₄] with friction braking systems.

Final status report on development of a new UN GTR for laboratory measurement of brake particle matter (PM) and particle number (PN) emissions from heavy-duty vehicles. The GTR introduces brake emissions groups based on fundamental design and performance characteristics, defines brake group nominal test parameters by disc or drum diameter, establishes friction braking share coefficients with c-factor = 1 for full-friction braking, specifies required test input parameters including brake system type and filtering systems, prescribes the Worldwide Harmonized Heavy-Duty Brake Cycle (WHBC) comprising 246 brake events over 5:39 hours across urban, rural, and motorway segments, defines PM and PN measurement methodologies using gravimetrical and particle number counter methods, specifies hardware requirements including brake dynamometer, enclosure dimensions of 1950 mm length × 1000 mm height × 700 mm depth with divider plate, sampling tunnel with 300 mm fixed inner diameter, and brake temperature measurement by embedded thermocouples, and includes results of preliminary interlaboratory study.

Proposal to amend UN GTR No. 24 by modifying test procedures, definitions, and requirements for brake particle emissions measurement. The amendment introduces improvements including revised definitions (vehicle electrification type, material formulation, pad size), updated measurement tolerances and signal filtering requirements, provisions for brake filtering systems, enhanced specifications for drum and electromechanical brake systems, relaxed cooling airflow adjustment requirements, and a new test cycle for speed-limited vehicles. Documentation of calibration requirements and ongoing quality controls are clarified throughout.

The document authorizes development of a new UN GTR on brake PM and PN emissions from all types of light-duty vehicle brake systems, including validation of the developed novel WLTP-Brake test cycle, investigation and selection of instrumentation and sampling methodology for brake wear particles, definition of minimum requirements for sampling, validation through interlaboratory study, inclusion of regenerative braking, and preparation of the PMP Brake protocol. It also reports on Amendment 2 to UN GTR No. 24 covering laboratory measurement of brake emissions for light-duty vehicles, detailing hardware requirements, test cycle specifications, cooling air conditioning, bedding procedures, and emissions measurement methodologies for particulate matter and particle number.

Proposal to amend Annex 2 – Appendix 1 to add para. 1.4.1. specifying user-selectable mode(s) resulting in the lowest recuperation and relevant pre-test procedures for vehicles with a vehicle specific c-factor according to Annex 5, and to delete items not brake emission related including brake circuit configuration, secondary braking system declaration, brake valve specifications, master cylinder type and size, and booster type and size.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter and particle number emissions from Heavy-Duty Vehicles. The UN GTR defines the test cycle (Worldwide Harmonized Heavy Duty Brake Cycle), minimum system requirements, test conditions, equipment preparation, brake dynamometer capabilities, brake enclosure design, sampling tunnel design, and sampling plane design. It applies to vehicles of categories M₂, M₃, N₂, N₃, and O₃, O₄ concerning braking, covering both friction braking systems (disc and drum brakes). The regulation includes requirements for brake bedding procedures, emissions measurements, calibration, and ongoing quality controls. A version with tracked changes is available.

Proposal to establish a new supplement to UN Regulation No. 179, improving and correcting brake emissions measurement procedures for light-duty vehicles of categories M₁ and N₁. The regulation applies full-friction braking testing on brake dynamometers using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. Testing includes three sections: cooling air adjustment, brake bedding with five cycle repetitions, and emissions measurement with three cycle repetitions. Compliance is demonstrated by measuring PM10 and SPN10 emissions from brake corner emission family parents, with whole-vehicle emissions calculated using friction braking share coefficients specific to vehicle electrification types. PM10 limits are 3 mg/km for M₁/N₁ vehicles and 5 mg/km for N₁ Class III/N₂ vehicles. Conformity of production requires annual testing of brake corner emission families with statistical evaluation per decision charts through 31 December 2029 (Phase I, PM10 only), with Phase II from 1 January 2030 evaluating both PM10 and SPN10. A version of this document with tracked changes is available.

Proposal to modify UN GTR No. 24 with respect to laboratory measurement procedures for brake emissions of light-duty vehicles. This amendment improves and corrects the testing procedure, including detailed requirements for test system setup, cooling air conditioning, brake dynamometer specifications, WLTP-Brake cycle execution, emissions measurements for particulate matter (PM2.5, PM10) and particle number (TPN10, SPN10), calibration protocols, and reporting of results. The regulation defines brake corner emissions families, friction braking share coefficients for different vehicle electrification types (ICE, HEV categories, PEV), and test procedures using fully-enclosed brake dynamometers with isokinetic sampling systems. A version with tracked changes is available.

Proposal to include testing of vehicles with limited speed. The document sets out the laboratory measurement procedure for brake emissions from light-duty vehicles of categories M₁ and N₁, including vehicles with maximum speed below the Base cycle maximum speed. Testing involves three sections: cooling air adjustment, brake bedding with five repetitions of the WLTP-Brake cycle, and brake emissions measurement with one WLTP-Brake cycle. Brake corner emission families are tested on a component test bench under full-friction braking conditions, measuring PM₁₀ and SPN₁₀ emissions. Compliance is demonstrated using brake corner emissions family parents. Conformity of production requires monthly sampling and testing of brake components, with results evaluated using statistical decision charts through 31 December 2029 for PM₁₀ and thereafter for both PM₁₀ and SPN₁₀.

Proposal to establish a new UN Regulation transposing UN GTR No. 24 into uniform provisions concerning approval of non-original and identical replacement brake parts (brake pads, drum brake linings, brake discs, and brake drums) with regards to particle emissions. The regulation applies to vehicles of category M₁, N₁, and N₂ between 3.5 and 5 tonnes maximum mass. Replacement brake parts must comply with particle emission limits, with emission factors calculated using test wheel load and friction braking share coefficient for the brake emissions family parent. Approval marks must be affixed to approved parts, and conformity of production shall be verified through sampling and testing procedures.

Proposal to amend and enhance the procedure for laboratory measurement of brake emissions for light-duty vehicles. The document provides comprehensive technical specifications covering scope and application for vehicles of categories M₁ and N₁, detailed abbreviations and symbols for measurement parameters, definitions of vehicle types and brake systems, application and approval procedures, conformity of production requirements with statistical evaluation procedures, and penalty provisions for non-conformity. Testing procedures include three sections: cooling air adjustment, brake bedding, and brake emissions measurement, all executed using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. CoP verification shall be performed once every 12 months with samples from each brake corner emission family, evaluated according to decision charts specified in the regulation.

Proposal to amend UN Regulation No. 179 to include testing of vehicles with limited speed. The document specifies amendments to the laboratory measurement of brake emissions for light-duty vehicles, including provisions for vehicles with a maximum speed lower than the maximum speed of the Base cycle. These vehicles may be part of the same brake corner emissions family as vehicles suitable for the Base cycle, with their emission factor calculated based on the parent family’s reference PM and PN emissions according to equations 7.1, 7.2 and 7.3. At the manufacturer’s request and with approval authority agreement, such limited-speed vehicles may be assigned to a specific family using the adjusted cycle described in Appendix 3 of Annex 4, with the same changes to be applied to UN GTR No. 24.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter (PM) and particle number (PN) emissions from heavy-duty vehicles, including trucks and buses, using a Worldwide Harmonized Heavy Duty Vehicles Brake Cycle (WHBC) and brake dynamometer testing. The GTR specifies test system requirements, including brake enclosure design, sampling tunnel specifications, climatic conditioning with cooling air temperature maintained at 23°C±2°C and relative humidity at 50%±5%, cooling airflow at 2500 Nm/h±5%, test preparation procedures, brake bedding with six repetitions of the WHBC followed by emissions measurement during one WHBC cycle, requirements for PM10, PM2.5, TPN10, and SPN10 measurement systems, brake temperature measurement using embedded thermocouples, calibration and validation procedures, and reporting of emission factors. The regulation applies to vehicles of categories M₂, M₃, N₂, N₃ [and O₃, O₄] with friction braking systems.

Final status report on development of a new UN GTR for laboratory measurement of brake particle matter (PM) and particle number (PN) emissions from heavy-duty vehicles. The GTR introduces brake emissions groups based on fundamental design and performance characteristics, defines brake group nominal test parameters by disc or drum diameter, establishes friction braking share coefficients with c-factor = 1 for full-friction braking, specifies required test input parameters including brake system type and filtering systems, prescribes the Worldwide Harmonized Heavy-Duty Brake Cycle (WHBC) comprising 246 brake events over 5:39 hours across urban, rural, and motorway segments, defines PM and PN measurement methodologies using gravimetrical and particle number counter methods, specifies hardware requirements including brake dynamometer, enclosure dimensions of 1950 mm length × 1000 mm height × 700 mm depth with divider plate, sampling tunnel with 300 mm fixed inner diameter, and brake temperature measurement by embedded thermocouples, and includes results of preliminary interlaboratory study.

Proposal to amend UN GTR No. 24 by modifying test procedures, definitions, and requirements for brake particle emissions measurement. The amendment introduces improvements including revised definitions (vehicle electrification type, material formulation, pad size), updated measurement tolerances and signal filtering requirements, provisions for brake filtering systems, enhanced specifications for drum and electromechanical brake systems, relaxed cooling airflow adjustment requirements, and a new test cycle for speed-limited vehicles. Documentation of calibration requirements and ongoing quality controls are clarified throughout.

The document authorizes development of a new UN GTR on brake PM and PN emissions from all types of light-duty vehicle brake systems, including validation of the developed novel WLTP-Brake test cycle, investigation and selection of instrumentation and sampling methodology for brake wear particles, definition of minimum requirements for sampling, validation through interlaboratory study, inclusion of regenerative braking, and preparation of the PMP Brake protocol. It also reports on Amendment 2 to UN GTR No. 24 covering laboratory measurement of brake emissions for light-duty vehicles, detailing hardware requirements, test cycle specifications, cooling air conditioning, bedding procedures, and emissions measurement methodologies for particulate matter and particle number.

Proposal to amend Annex 2 – Appendix 1 to add para. 1.4.1. specifying user-selectable mode(s) resulting in the lowest recuperation and relevant pre-test procedures for vehicles with a vehicle specific c-factor according to Annex 5, and to delete items not brake emission related including brake circuit configuration, secondary braking system declaration, brake valve specifications, master cylinder type and size, and booster type and size.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter and particle number emissions from Heavy-Duty Vehicles. The UN GTR defines the test cycle (Worldwide Harmonized Heavy Duty Brake Cycle), minimum system requirements, test conditions, equipment preparation, brake dynamometer capabilities, brake enclosure design, sampling tunnel design, and sampling plane design. It applies to vehicles of categories M₂, M₃, N₂, N₃, and O₃, O₄ concerning braking, covering both friction braking systems (disc and drum brakes). The regulation includes requirements for brake bedding procedures, emissions measurements, calibration, and ongoing quality controls. A version with tracked changes is available.

Proposal to establish a new supplement to UN Regulation No. 179, improving and correcting brake emissions measurement procedures for light-duty vehicles of categories M₁ and N₁. The regulation applies full-friction braking testing on brake dynamometers using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. Testing includes three sections: cooling air adjustment, brake bedding with five cycle repetitions, and emissions measurement with three cycle repetitions. Compliance is demonstrated by measuring PM10 and SPN10 emissions from brake corner emission family parents, with whole-vehicle emissions calculated using friction braking share coefficients specific to vehicle electrification types. PM10 limits are 3 mg/km for M₁/N₁ vehicles and 5 mg/km for N₁ Class III/N₂ vehicles. Conformity of production requires annual testing of brake corner emission families with statistical evaluation per decision charts through 31 December 2029 (Phase I, PM10 only), with Phase II from 1 January 2030 evaluating both PM10 and SPN10. A version of this document with tracked changes is available.

Proposal to modify UN GTR No. 24 with respect to laboratory measurement procedures for brake emissions of light-duty vehicles. This amendment improves and corrects the testing procedure, including detailed requirements for test system setup, cooling air conditioning, brake dynamometer specifications, WLTP-Brake cycle execution, emissions measurements for particulate matter (PM2.5, PM10) and particle number (TPN10, SPN10), calibration protocols, and reporting of results. The regulation defines brake corner emissions families, friction braking share coefficients for different vehicle electrification types (ICE, HEV categories, PEV), and test procedures using fully-enclosed brake dynamometers with isokinetic sampling systems. A version with tracked changes is available.

Proposal to include testing of vehicles with limited speed. The document sets out the laboratory measurement procedure for brake emissions from light-duty vehicles of categories M₁ and N₁, including vehicles with maximum speed below the Base cycle maximum speed. Testing involves three sections: cooling air adjustment, brake bedding with five repetitions of the WLTP-Brake cycle, and brake emissions measurement with one WLTP-Brake cycle. Brake corner emission families are tested on a component test bench under full-friction braking conditions, measuring PM₁₀ and SPN₁₀ emissions. Compliance is demonstrated using brake corner emissions family parents. Conformity of production requires monthly sampling and testing of brake components, with results evaluated using statistical decision charts through 31 December 2029 for PM₁₀ and thereafter for both PM₁₀ and SPN₁₀.

Proposal to establish a new UN Regulation transposing UN GTR No. 24 into uniform provisions concerning approval of non-original and identical replacement brake parts (brake pads, drum brake linings, brake discs, and brake drums) with regards to particle emissions. The regulation applies to vehicles of category M₁, N₁, and N₂ between 3.5 and 5 tonnes maximum mass. Replacement brake parts must comply with particle emission limits, with emission factors calculated using test wheel load and friction braking share coefficient for the brake emissions family parent. Approval marks must be affixed to approved parts, and conformity of production shall be verified through sampling and testing procedures.

Proposal to amend and enhance the procedure for laboratory measurement of brake emissions for light-duty vehicles. The document provides comprehensive technical specifications covering scope and application for vehicles of categories M₁ and N₁, detailed abbreviations and symbols for measurement parameters, definitions of vehicle types and brake systems, application and approval procedures, conformity of production requirements with statistical evaluation procedures, and penalty provisions for non-conformity. Testing procedures include three sections: cooling air adjustment, brake bedding, and brake emissions measurement, all executed using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. CoP verification shall be performed once every 12 months with samples from each brake corner emission family, evaluated according to decision charts specified in the regulation.

Proposal to amend UN Regulation No. 179 to include testing of vehicles with limited speed. The document specifies amendments to the laboratory measurement of brake emissions for light-duty vehicles, including provisions for vehicles with a maximum speed lower than the maximum speed of the Base cycle. These vehicles may be part of the same brake corner emissions family as vehicles suitable for the Base cycle, with their emission factor calculated based on the parent family’s reference PM and PN emissions according to equations 7.1, 7.2 and 7.3. At the manufacturer’s request and with approval authority agreement, such limited-speed vehicles may be assigned to a specific family using the adjusted cycle described in Appendix 3 of Annex 4, with the same changes to be applied to UN GTR No. 24.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter (PM) and particle number (PN) emissions from heavy-duty vehicles, including trucks and buses, using a Worldwide Harmonized Heavy Duty Vehicles Brake Cycle (WHBC) and brake dynamometer testing. The GTR specifies test system requirements, including brake enclosure design, sampling tunnel specifications, climatic conditioning with cooling air temperature maintained at 23°C±2°C and relative humidity at 50%±5%, cooling airflow at 2500 Nm/h±5%, test preparation procedures, brake bedding with six repetitions of the WHBC followed by emissions measurement during one WHBC cycle, requirements for PM10, PM2.5, TPN10, and SPN10 measurement systems, brake temperature measurement using embedded thermocouples, calibration and validation procedures, and reporting of emission factors. The regulation applies to vehicles of categories M₂, M₃, N₂, N₃ [and O₃, O₄] with friction braking systems.

Final status report on development of a new UN GTR for laboratory measurement of brake particle matter (PM) and particle number (PN) emissions from heavy-duty vehicles. The GTR introduces brake emissions groups based on fundamental design and performance characteristics, defines brake group nominal test parameters by disc or drum diameter, establishes friction braking share coefficients with c-factor = 1 for full-friction braking, specifies required test input parameters including brake system type and filtering systems, prescribes the Worldwide Harmonized Heavy-Duty Brake Cycle (WHBC) comprising 246 brake events over 5:39 hours across urban, rural, and motorway segments, defines PM and PN measurement methodologies using gravimetrical and particle number counter methods, specifies hardware requirements including brake dynamometer, enclosure dimensions of 1950 mm length × 1000 mm height × 700 mm depth with divider plate, sampling tunnel with 300 mm fixed inner diameter, and brake temperature measurement by embedded thermocouples, and includes results of preliminary interlaboratory study.

Proposal to amend UN GTR No. 24 by modifying test procedures, definitions, and requirements for brake particle emissions measurement. The amendment introduces improvements including revised definitions (vehicle electrification type, material formulation, pad size), updated measurement tolerances and signal filtering requirements, provisions for brake filtering systems, enhanced specifications for drum and electromechanical brake systems, relaxed cooling airflow adjustment requirements, and a new test cycle for speed-limited vehicles. Documentation of calibration requirements and ongoing quality controls are clarified throughout.

The document authorizes development of a new UN GTR on brake PM and PN emissions from all types of light-duty vehicle brake systems, including validation of the developed novel WLTP-Brake test cycle, investigation and selection of instrumentation and sampling methodology for brake wear particles, definition of minimum requirements for sampling, validation through interlaboratory study, inclusion of regenerative braking, and preparation of the PMP Brake protocol. It also reports on Amendment 2 to UN GTR No. 24 covering laboratory measurement of brake emissions for light-duty vehicles, detailing hardware requirements, test cycle specifications, cooling air conditioning, bedding procedures, and emissions measurement methodologies for particulate matter and particle number.

Proposal to amend Annex 2 – Appendix 1 to add para. 1.4.1. specifying user-selectable mode(s) resulting in the lowest recuperation and relevant pre-test procedures for vehicles with a vehicle specific c-factor according to Annex 5, and to delete items not brake emission related including brake circuit configuration, secondary braking system declaration, brake valve specifications, master cylinder type and size, and booster type and size.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter and particle number emissions from Heavy-Duty Vehicles. The UN GTR defines the test cycle (Worldwide Harmonized Heavy Duty Brake Cycle), minimum system requirements, test conditions, equipment preparation, brake dynamometer capabilities, brake enclosure design, sampling tunnel design, and sampling plane design. It applies to vehicles of categories M₂, M₃, N₂, N₃, and O₃, O₄ concerning braking, covering both friction braking systems (disc and drum brakes). The regulation includes requirements for brake bedding procedures, emissions measurements, calibration, and ongoing quality controls. A version with tracked changes is available.

Proposal to establish a new supplement to UN Regulation No. 179, improving and correcting brake emissions measurement procedures for light-duty vehicles of categories M₁ and N₁. The regulation applies full-friction braking testing on brake dynamometers using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. Testing includes three sections: cooling air adjustment, brake bedding with five cycle repetitions, and emissions measurement with three cycle repetitions. Compliance is demonstrated by measuring PM10 and SPN10 emissions from brake corner emission family parents, with whole-vehicle emissions calculated using friction braking share coefficients specific to vehicle electrification types. PM10 limits are 3 mg/km for M₁/N₁ vehicles and 5 mg/km for N₁ Class III/N₂ vehicles. Conformity of production requires annual testing of brake corner emission families with statistical evaluation per decision charts through 31 December 2029 (Phase I, PM10 only), with Phase II from 1 January 2030 evaluating both PM10 and SPN10. A version of this document with tracked changes is available.

Proposal to modify UN GTR No. 24 with respect to laboratory measurement procedures for brake emissions of light-duty vehicles. This amendment improves and corrects the testing procedure, including detailed requirements for test system setup, cooling air conditioning, brake dynamometer specifications, WLTP-Brake cycle execution, emissions measurements for particulate matter (PM2.5, PM10) and particle number (TPN10, SPN10), calibration protocols, and reporting of results. The regulation defines brake corner emissions families, friction braking share coefficients for different vehicle electrification types (ICE, HEV categories, PEV), and test procedures using fully-enclosed brake dynamometers with isokinetic sampling systems. A version with tracked changes is available.

Proposal to include testing of vehicles with limited speed. The document sets out the laboratory measurement procedure for brake emissions from light-duty vehicles of categories M₁ and N₁, including vehicles with maximum speed below the Base cycle maximum speed. Testing involves three sections: cooling air adjustment, brake bedding with five repetitions of the WLTP-Brake cycle, and brake emissions measurement with one WLTP-Brake cycle. Brake corner emission families are tested on a component test bench under full-friction braking conditions, measuring PM₁₀ and SPN₁₀ emissions. Compliance is demonstrated using brake corner emissions family parents. Conformity of production requires monthly sampling and testing of brake components, with results evaluated using statistical decision charts through 31 December 2029 for PM₁₀ and thereafter for both PM₁₀ and SPN₁₀.

Proposal to establish a new UN Regulation transposing UN GTR No. 24 into uniform provisions concerning approval of non-original and identical replacement brake parts (brake pads, drum brake linings, brake discs, and brake drums) with regards to particle emissions. The regulation applies to vehicles of category M₁, N₁, and N₂ between 3.5 and 5 tonnes maximum mass. Replacement brake parts must comply with particle emission limits, with emission factors calculated using test wheel load and friction braking share coefficient for the brake emissions family parent. Approval marks must be affixed to approved parts, and conformity of production shall be verified through sampling and testing procedures.

Proposal to amend and enhance the procedure for laboratory measurement of brake emissions for light-duty vehicles. The document provides comprehensive technical specifications covering scope and application for vehicles of categories M₁ and N₁, detailed abbreviations and symbols for measurement parameters, definitions of vehicle types and brake systems, application and approval procedures, conformity of production requirements with statistical evaluation procedures, and penalty provisions for non-conformity. Testing procedures include three sections: cooling air adjustment, brake bedding, and brake emissions measurement, all executed using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. CoP verification shall be performed once every 12 months with samples from each brake corner emission family, evaluated according to decision charts specified in the regulation.

Proposal to amend UN Regulation No. 179 to include testing of vehicles with limited speed. The document specifies amendments to the laboratory measurement of brake emissions for light-duty vehicles, including provisions for vehicles with a maximum speed lower than the maximum speed of the Base cycle. These vehicles may be part of the same brake corner emissions family as vehicles suitable for the Base cycle, with their emission factor calculated based on the parent family’s reference PM and PN emissions according to equations 7.1, 7.2 and 7.3. At the manufacturer’s request and with approval authority agreement, such limited-speed vehicles may be assigned to a specific family using the adjusted cycle described in Appendix 3 of Annex 4, with the same changes to be applied to UN GTR No. 24.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter (PM) and particle number (PN) emissions from heavy-duty vehicles, including trucks and buses, using a Worldwide Harmonized Heavy Duty Vehicles Brake Cycle (WHBC) and brake dynamometer testing. The GTR specifies test system requirements, including brake enclosure design, sampling tunnel specifications, climatic conditioning with cooling air temperature maintained at 23°C±2°C and relative humidity at 50%±5%, cooling airflow at 2500 Nm/h±5%, test preparation procedures, brake bedding with six repetitions of the WHBC followed by emissions measurement during one WHBC cycle, requirements for PM10, PM2.5, TPN10, and SPN10 measurement systems, brake temperature measurement using embedded thermocouples, calibration and validation procedures, and reporting of emission factors. The regulation applies to vehicles of categories M₂, M₃, N₂, N₃ [and O₃, O₄] with friction braking systems.

Final status report on development of a new UN GTR for laboratory measurement of brake particle matter (PM) and particle number (PN) emissions from heavy-duty vehicles. The GTR introduces brake emissions groups based on fundamental design and performance characteristics, defines brake group nominal test parameters by disc or drum diameter, establishes friction braking share coefficients with c-factor = 1 for full-friction braking, specifies required test input parameters including brake system type and filtering systems, prescribes the Worldwide Harmonized Heavy-Duty Brake Cycle (WHBC) comprising 246 brake events over 5:39 hours across urban, rural, and motorway segments, defines PM and PN measurement methodologies using gravimetrical and particle number counter methods, specifies hardware requirements including brake dynamometer, enclosure dimensions of 1950 mm length × 1000 mm height × 700 mm depth with divider plate, sampling tunnel with 300 mm fixed inner diameter, and brake temperature measurement by embedded thermocouples, and includes results of preliminary interlaboratory study.

Proposal to amend UN GTR No. 24 by modifying test procedures, definitions, and requirements for brake particle emissions measurement. The amendment introduces improvements including revised definitions (vehicle electrification type, material formulation, pad size), updated measurement tolerances and signal filtering requirements, provisions for brake filtering systems, enhanced specifications for drum and electromechanical brake systems, relaxed cooling airflow adjustment requirements, and a new test cycle for speed-limited vehicles. Documentation of calibration requirements and ongoing quality controls are clarified throughout.

The document authorizes development of a new UN GTR on brake PM and PN emissions from all types of light-duty vehicle brake systems, including validation of the developed novel WLTP-Brake test cycle, investigation and selection of instrumentation and sampling methodology for brake wear particles, definition of minimum requirements for sampling, validation through interlaboratory study, inclusion of regenerative braking, and preparation of the PMP Brake protocol. It also reports on Amendment 2 to UN GTR No. 24 covering laboratory measurement of brake emissions for light-duty vehicles, detailing hardware requirements, test cycle specifications, cooling air conditioning, bedding procedures, and emissions measurement methodologies for particulate matter and particle number.

Proposal to amend Annex 2 – Appendix 1 to add para. 1.4.1. specifying user-selectable mode(s) resulting in the lowest recuperation and relevant pre-test procedures for vehicles with a vehicle specific c-factor according to Annex 5, and to delete items not brake emission related including brake circuit configuration, secondary braking system declaration, brake valve specifications, master cylinder type and size, and booster type and size.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter and particle number emissions from Heavy-Duty Vehicles. The UN GTR defines the test cycle (Worldwide Harmonized Heavy Duty Brake Cycle), minimum system requirements, test conditions, equipment preparation, brake dynamometer capabilities, brake enclosure design, sampling tunnel design, and sampling plane design. It applies to vehicles of categories M₂, M₃, N₂, N₃, and O₃, O₄ concerning braking, covering both friction braking systems (disc and drum brakes). The regulation includes requirements for brake bedding procedures, emissions measurements, calibration, and ongoing quality controls. A version with tracked changes is available.

Proposal to establish a new supplement to UN Regulation No. 179, improving and correcting brake emissions measurement procedures for light-duty vehicles of categories M₁ and N₁. The regulation applies full-friction braking testing on brake dynamometers using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. Testing includes three sections: cooling air adjustment, brake bedding with five cycle repetitions, and emissions measurement with three cycle repetitions. Compliance is demonstrated by measuring PM10 and SPN10 emissions from brake corner emission family parents, with whole-vehicle emissions calculated using friction braking share coefficients specific to vehicle electrification types. PM10 limits are 3 mg/km for M₁/N₁ vehicles and 5 mg/km for N₁ Class III/N₂ vehicles. Conformity of production requires annual testing of brake corner emission families with statistical evaluation per decision charts through 31 December 2029 (Phase I, PM10 only), with Phase II from 1 January 2030 evaluating both PM10 and SPN10. A version of this document with tracked changes is available.

Proposal to modify UN GTR No. 24 with respect to laboratory measurement procedures for brake emissions of light-duty vehicles. This amendment improves and corrects the testing procedure, including detailed requirements for test system setup, cooling air conditioning, brake dynamometer specifications, WLTP-Brake cycle execution, emissions measurements for particulate matter (PM2.5, PM10) and particle number (TPN10, SPN10), calibration protocols, and reporting of results. The regulation defines brake corner emissions families, friction braking share coefficients for different vehicle electrification types (ICE, HEV categories, PEV), and test procedures using fully-enclosed brake dynamometers with isokinetic sampling systems. A version with tracked changes is available.

Proposal to include testing of vehicles with limited speed. The document sets out the laboratory measurement procedure for brake emissions from light-duty vehicles of categories M₁ and N₁, including vehicles with maximum speed below the Base cycle maximum speed. Testing involves three sections: cooling air adjustment, brake bedding with five repetitions of the WLTP-Brake cycle, and brake emissions measurement with one WLTP-Brake cycle. Brake corner emission families are tested on a component test bench under full-friction braking conditions, measuring PM₁₀ and SPN₁₀ emissions. Compliance is demonstrated using brake corner emissions family parents. Conformity of production requires monthly sampling and testing of brake components, with results evaluated using statistical decision charts through 31 December 2029 for PM₁₀ and thereafter for both PM₁₀ and SPN₁₀.

Proposal to establish a new UN Regulation transposing UN GTR No. 24 into uniform provisions concerning approval of non-original and identical replacement brake parts (brake pads, drum brake linings, brake discs, and brake drums) with regards to particle emissions. The regulation applies to vehicles of category M₁, N₁, and N₂ between 3.5 and 5 tonnes maximum mass. Replacement brake parts must comply with particle emission limits, with emission factors calculated using test wheel load and friction braking share coefficient for the brake emissions family parent. Approval marks must be affixed to approved parts, and conformity of production shall be verified through sampling and testing procedures.

Proposal to amend and enhance the procedure for laboratory measurement of brake emissions for light-duty vehicles. The document provides comprehensive technical specifications covering scope and application for vehicles of categories M₁ and N₁, detailed abbreviations and symbols for measurement parameters, definitions of vehicle types and brake systems, application and approval procedures, conformity of production requirements with statistical evaluation procedures, and penalty provisions for non-conformity. Testing procedures include three sections: cooling air adjustment, brake bedding, and brake emissions measurement, all executed using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. CoP verification shall be performed once every 12 months with samples from each brake corner emission family, evaluated according to decision charts specified in the regulation.

Proposal to amend UN Regulation No. 179 to include testing of vehicles with limited speed. The document specifies amendments to the laboratory measurement of brake emissions for light-duty vehicles, including provisions for vehicles with a maximum speed lower than the maximum speed of the Base cycle. These vehicles may be part of the same brake corner emissions family as vehicles suitable for the Base cycle, with their emission factor calculated based on the parent family’s reference PM and PN emissions according to equations 7.1, 7.2 and 7.3. At the manufacturer’s request and with approval authority agreement, such limited-speed vehicles may be assigned to a specific family using the adjusted cycle described in Appendix 3 of Annex 4, with the same changes to be applied to UN GTR No. 24.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter (PM) and particle number (PN) emissions from heavy-duty vehicles, including trucks and buses, using a Worldwide Harmonized Heavy Duty Vehicles Brake Cycle (WHBC) and brake dynamometer testing. The GTR specifies test system requirements, including brake enclosure design, sampling tunnel specifications, climatic conditioning with cooling air temperature maintained at 23°C±2°C and relative humidity at 50%±5%, cooling airflow at 2500 Nm/h±5%, test preparation procedures, brake bedding with six repetitions of the WHBC followed by emissions measurement during one WHBC cycle, requirements for PM10, PM2.5, TPN10, and SPN10 measurement systems, brake temperature measurement using embedded thermocouples, calibration and validation procedures, and reporting of emission factors. The regulation applies to vehicles of categories M₂, M₃, N₂, N₃ [and O₃, O₄] with friction braking systems.

Final status report on development of a new UN GTR for laboratory measurement of brake particle matter (PM) and particle number (PN) emissions from heavy-duty vehicles. The GTR introduces brake emissions groups based on fundamental design and performance characteristics, defines brake group nominal test parameters by disc or drum diameter, establishes friction braking share coefficients with c-factor = 1 for full-friction braking, specifies required test input parameters including brake system type and filtering systems, prescribes the Worldwide Harmonized Heavy-Duty Brake Cycle (WHBC) comprising 246 brake events over 5:39 hours across urban, rural, and motorway segments, defines PM and PN measurement methodologies using gravimetrical and particle number counter methods, specifies hardware requirements including brake dynamometer, enclosure dimensions of 1950 mm length × 1000 mm height × 700 mm depth with divider plate, sampling tunnel with 300 mm fixed inner diameter, and brake temperature measurement by embedded thermocouples, and includes results of preliminary interlaboratory study.

Proposal to amend UN GTR No. 24 by modifying test procedures, definitions, and requirements for brake particle emissions measurement. The amendment introduces improvements including revised definitions (vehicle electrification type, material formulation, pad size), updated measurement tolerances and signal filtering requirements, provisions for brake filtering systems, enhanced specifications for drum and electromechanical brake systems, relaxed cooling airflow adjustment requirements, and a new test cycle for speed-limited vehicles. Documentation of calibration requirements and ongoing quality controls are clarified throughout.

The document authorizes development of a new UN GTR on brake PM and PN emissions from all types of light-duty vehicle brake systems, including validation of the developed novel WLTP-Brake test cycle, investigation and selection of instrumentation and sampling methodology for brake wear particles, definition of minimum requirements for sampling, validation through interlaboratory study, inclusion of regenerative braking, and preparation of the PMP Brake protocol. It also reports on Amendment 2 to UN GTR No. 24 covering laboratory measurement of brake emissions for light-duty vehicles, detailing hardware requirements, test cycle specifications, cooling air conditioning, bedding procedures, and emissions measurement methodologies for particulate matter and particle number.

Proposal to amend Annex 2 – Appendix 1 to add para. 1.4.1. specifying user-selectable mode(s) resulting in the lowest recuperation and relevant pre-test procedures for vehicles with a vehicle specific c-factor according to Annex 5, and to delete items not brake emission related including brake circuit configuration, secondary braking system declaration, brake valve specifications, master cylinder type and size, and booster type and size.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter and particle number emissions from Heavy-Duty Vehicles. The UN GTR defines the test cycle (Worldwide Harmonized Heavy Duty Brake Cycle), minimum system requirements, test conditions, equipment preparation, brake dynamometer capabilities, brake enclosure design, sampling tunnel design, and sampling plane design. It applies to vehicles of categories M₂, M₃, N₂, N₃, and O₃, O₄ concerning braking, covering both friction braking systems (disc and drum brakes). The regulation includes requirements for brake bedding procedures, emissions measurements, calibration, and ongoing quality controls. A version with tracked changes is available.

Proposal to establish a new supplement to UN Regulation No. 179, improving and correcting brake emissions measurement procedures for light-duty vehicles of categories M₁ and N₁. The regulation applies full-friction braking testing on brake dynamometers using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. Testing includes three sections: cooling air adjustment, brake bedding with five cycle repetitions, and emissions measurement with three cycle repetitions. Compliance is demonstrated by measuring PM10 and SPN10 emissions from brake corner emission family parents, with whole-vehicle emissions calculated using friction braking share coefficients specific to vehicle electrification types. PM10 limits are 3 mg/km for M₁/N₁ vehicles and 5 mg/km for N₁ Class III/N₂ vehicles. Conformity of production requires annual testing of brake corner emission families with statistical evaluation per decision charts through 31 December 2029 (Phase I, PM10 only), with Phase II from 1 January 2030 evaluating both PM10 and SPN10. A version of this document with tracked changes is available.

Proposal to modify UN GTR No. 24 with respect to laboratory measurement procedures for brake emissions of light-duty vehicles. This amendment improves and corrects the testing procedure, including detailed requirements for test system setup, cooling air conditioning, brake dynamometer specifications, WLTP-Brake cycle execution, emissions measurements for particulate matter (PM2.5, PM10) and particle number (TPN10, SPN10), calibration protocols, and reporting of results. The regulation defines brake corner emissions families, friction braking share coefficients for different vehicle electrification types (ICE, HEV categories, PEV), and test procedures using fully-enclosed brake dynamometers with isokinetic sampling systems. A version with tracked changes is available.

Proposal to include testing of vehicles with limited speed. The document sets out the laboratory measurement procedure for brake emissions from light-duty vehicles of categories M₁ and N₁, including vehicles with maximum speed below the Base cycle maximum speed. Testing involves three sections: cooling air adjustment, brake bedding with five repetitions of the WLTP-Brake cycle, and brake emissions measurement with one WLTP-Brake cycle. Brake corner emission families are tested on a component test bench under full-friction braking conditions, measuring PM₁₀ and SPN₁₀ emissions. Compliance is demonstrated using brake corner emissions family parents. Conformity of production requires monthly sampling and testing of brake components, with results evaluated using statistical decision charts through 31 December 2029 for PM₁₀ and thereafter for both PM₁₀ and SPN₁₀.

Proposal to establish a new UN Regulation transposing UN GTR No. 24 into uniform provisions concerning approval of non-original and identical replacement brake parts (brake pads, drum brake linings, brake discs, and brake drums) with regards to particle emissions. The regulation applies to vehicles of category M₁, N₁, and N₂ between 3.5 and 5 tonnes maximum mass. Replacement brake parts must comply with particle emission limits, with emission factors calculated using test wheel load and friction braking share coefficient for the brake emissions family parent. Approval marks must be affixed to approved parts, and conformity of production shall be verified through sampling and testing procedures.

Proposal to amend and enhance the procedure for laboratory measurement of brake emissions for light-duty vehicles. The document provides comprehensive technical specifications covering scope and application for vehicles of categories M₁ and N₁, detailed abbreviations and symbols for measurement parameters, definitions of vehicle types and brake systems, application and approval procedures, conformity of production requirements with statistical evaluation procedures, and penalty provisions for non-conformity. Testing procedures include three sections: cooling air adjustment, brake bedding, and brake emissions measurement, all executed using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. CoP verification shall be performed once every 12 months with samples from each brake corner emission family, evaluated according to decision charts specified in the regulation.

Proposal to amend UN Regulation No. 179 to include testing of vehicles with limited speed. The document specifies amendments to the laboratory measurement of brake emissions for light-duty vehicles, including provisions for vehicles with a maximum speed lower than the maximum speed of the Base cycle. These vehicles may be part of the same brake corner emissions family as vehicles suitable for the Base cycle, with their emission factor calculated based on the parent family’s reference PM and PN emissions according to equations 7.1, 7.2 and 7.3. At the manufacturer’s request and with approval authority agreement, such limited-speed vehicles may be assigned to a specific family using the adjusted cycle described in Appendix 3 of Annex 4, with the same changes to be applied to UN GTR No. 24.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter (PM) and particle number (PN) emissions from heavy-duty vehicles, including trucks and buses, using a Worldwide Harmonized Heavy Duty Vehicles Brake Cycle (WHBC) and brake dynamometer testing. The GTR specifies test system requirements, including brake enclosure design, sampling tunnel specifications, climatic conditioning with cooling air temperature maintained at 23°C±2°C and relative humidity at 50%±5%, cooling airflow at 2500 Nm/h±5%, test preparation procedures, brake bedding with six repetitions of the WHBC followed by emissions measurement during one WHBC cycle, requirements for PM10, PM2.5, TPN10, and SPN10 measurement systems, brake temperature measurement using embedded thermocouples, calibration and validation procedures, and reporting of emission factors. The regulation applies to vehicles of categories M₂, M₃, N₂, N₃ [and O₃, O₄] with friction braking systems.

Final status report on development of a new UN GTR for laboratory measurement of brake particle matter (PM) and particle number (PN) emissions from heavy-duty vehicles. The GTR introduces brake emissions groups based on fundamental design and performance characteristics, defines brake group nominal test parameters by disc or drum diameter, establishes friction braking share coefficients with c-factor = 1 for full-friction braking, specifies required test input parameters including brake system type and filtering systems, prescribes the Worldwide Harmonized Heavy-Duty Brake Cycle (WHBC) comprising 246 brake events over 5:39 hours across urban, rural, and motorway segments, defines PM and PN measurement methodologies using gravimetrical and particle number counter methods, specifies hardware requirements including brake dynamometer, enclosure dimensions of 1950 mm length × 1000 mm height × 700 mm depth with divider plate, sampling tunnel with 300 mm fixed inner diameter, and brake temperature measurement by embedded thermocouples, and includes results of preliminary interlaboratory study.

Proposal to amend UN GTR No. 24 by modifying test procedures, definitions, and requirements for brake particle emissions measurement. The amendment introduces improvements including revised definitions (vehicle electrification type, material formulation, pad size), updated measurement tolerances and signal filtering requirements, provisions for brake filtering systems, enhanced specifications for drum and electromechanical brake systems, relaxed cooling airflow adjustment requirements, and a new test cycle for speed-limited vehicles. Documentation of calibration requirements and ongoing quality controls are clarified throughout.

The document authorizes development of a new UN GTR on brake PM and PN emissions from all types of light-duty vehicle brake systems, including validation of the developed novel WLTP-Brake test cycle, investigation and selection of instrumentation and sampling methodology for brake wear particles, definition of minimum requirements for sampling, validation through interlaboratory study, inclusion of regenerative braking, and preparation of the PMP Brake protocol. It also reports on Amendment 2 to UN GTR No. 24 covering laboratory measurement of brake emissions for light-duty vehicles, detailing hardware requirements, test cycle specifications, cooling air conditioning, bedding procedures, and emissions measurement methodologies for particulate matter and particle number.

Proposal to amend Annex 2 – Appendix 1 to add para. 1.4.1. specifying user-selectable mode(s) resulting in the lowest recuperation and relevant pre-test procedures for vehicles with a vehicle specific c-factor according to Annex 5, and to delete items not brake emission related including brake circuit configuration, secondary braking system declaration, brake valve specifications, master cylinder type and size, and booster type and size.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter and particle number emissions from Heavy-Duty Vehicles. The UN GTR defines the test cycle (Worldwide Harmonized Heavy Duty Brake Cycle), minimum system requirements, test conditions, equipment preparation, brake dynamometer capabilities, brake enclosure design, sampling tunnel design, and sampling plane design. It applies to vehicles of categories M₂, M₃, N₂, N₃, and O₃, O₄ concerning braking, covering both friction braking systems (disc and drum brakes). The regulation includes requirements for brake bedding procedures, emissions measurements, calibration, and ongoing quality controls. A version with tracked changes is available.

Proposal to establish a new supplement to UN Regulation No. 179, improving and correcting brake emissions measurement procedures for light-duty vehicles of categories M₁ and N₁. The regulation applies full-friction braking testing on brake dynamometers using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. Testing includes three sections: cooling air adjustment, brake bedding with five cycle repetitions, and emissions measurement with three cycle repetitions. Compliance is demonstrated by measuring PM10 and SPN10 emissions from brake corner emission family parents, with whole-vehicle emissions calculated using friction braking share coefficients specific to vehicle electrification types. PM10 limits are 3 mg/km for M₁/N₁ vehicles and 5 mg/km for N₁ Class III/N₂ vehicles. Conformity of production requires annual testing of brake corner emission families with statistical evaluation per decision charts through 31 December 2029 (Phase I, PM10 only), with Phase II from 1 January 2030 evaluating both PM10 and SPN10. A version of this document with tracked changes is available.

Proposal to modify UN GTR No. 24 with respect to laboratory measurement procedures for brake emissions of light-duty vehicles. This amendment improves and corrects the testing procedure, including detailed requirements for test system setup, cooling air conditioning, brake dynamometer specifications, WLTP-Brake cycle execution, emissions measurements for particulate matter (PM2.5, PM10) and particle number (TPN10, SPN10), calibration protocols, and reporting of results. The regulation defines brake corner emissions families, friction braking share coefficients for different vehicle electrification types (ICE, HEV categories, PEV), and test procedures using fully-enclosed brake dynamometers with isokinetic sampling systems. A version with tracked changes is available.

Proposal to include testing of vehicles with limited speed. The document sets out the laboratory measurement procedure for brake emissions from light-duty vehicles of categories M₁ and N₁, including vehicles with maximum speed below the Base cycle maximum speed. Testing involves three sections: cooling air adjustment, brake bedding with five repetitions of the WLTP-Brake cycle, and brake emissions measurement with one WLTP-Brake cycle. Brake corner emission families are tested on a component test bench under full-friction braking conditions, measuring PM₁₀ and SPN₁₀ emissions. Compliance is demonstrated using brake corner emissions family parents. Conformity of production requires monthly sampling and testing of brake components, with results evaluated using statistical decision charts through 31 December 2029 for PM₁₀ and thereafter for both PM₁₀ and SPN₁₀.

Proposal to establish a new UN Regulation transposing UN GTR No. 24 into uniform provisions concerning approval of non-original and identical replacement brake parts (brake pads, drum brake linings, brake discs, and brake drums) with regards to particle emissions. The regulation applies to vehicles of category M₁, N₁, and N₂ between 3.5 and 5 tonnes maximum mass. Replacement brake parts must comply with particle emission limits, with emission factors calculated using test wheel load and friction braking share coefficient for the brake emissions family parent. Approval marks must be affixed to approved parts, and conformity of production shall be verified through sampling and testing procedures.

Proposal to amend and enhance the procedure for laboratory measurement of brake emissions for light-duty vehicles. The document provides comprehensive technical specifications covering scope and application for vehicles of categories M₁ and N₁, detailed abbreviations and symbols for measurement parameters, definitions of vehicle types and brake systems, application and approval procedures, conformity of production requirements with statistical evaluation procedures, and penalty provisions for non-conformity. Testing procedures include three sections: cooling air adjustment, brake bedding, and brake emissions measurement, all executed using the WLTP-Brake cycle comprising ten trips and 303 brake deceleration events. CoP verification shall be performed once every 12 months with samples from each brake corner emission family, evaluated according to decision charts specified in the regulation.

Proposal to amend UN Regulation No. 179 to include testing of vehicles with limited speed. The document specifies amendments to the laboratory measurement of brake emissions for light-duty vehicles, including provisions for vehicles with a maximum speed lower than the maximum speed of the Base cycle. These vehicles may be part of the same brake corner emissions family as vehicles suitable for the Base cycle, with their emission factor calculated based on the parent family’s reference PM and PN emissions according to equations 7.1, 7.2 and 7.3. At the manufacturer’s request and with approval authority agreement, such limited-speed vehicles may be assigned to a specific family using the adjusted cycle described in Appendix 3 of Annex 4, with the same changes to be applied to UN GTR No. 24.

Proposal to establish a globally harmonised laboratory methodology for measuring brake particulate matter (PM) and particle number (PN) emissions from heavy-duty vehicles, including trucks and buses, using a Worldwide Harmonized Heavy Duty Vehicles Brake Cycle (WHBC) and brake dynamometer testing. The GTR specifies test system requirements, including brake enclosure design, sampling tunnel specifications, climatic conditioning with cooling air temperature maintained at 23°C±2°C and relative humidity at 50%±5%, cooling airflow at 2500 Nm/h±5%, test preparation procedures, brake bedding with six repetitions of the WHBC followed by emissions measurement during one WHBC cycle, requirements for PM10, PM2.5, TPN10, and SPN10 measurement systems, brake temperature measurement using embedded thermocouples, calibration and validation procedures, and reporting of emission factors. The regulation applies to vehicles of categories M₂, M₃, N₂, N₃ [and O₃, O₄] with friction braking systems.

Final status report on development of a new UN GTR for laboratory measurement of brake particle matter (PM) and particle number (PN) emissions from heavy-duty vehicles. The GTR introduces brake emissions groups based on fundamental design and performance characteristics, defines brake group nominal test parameters by disc or drum diameter, establishes friction braking share coefficients with c-factor = 1 for full-friction braking, specifies required test input parameters including brake system type and filtering systems, prescribes the Worldwide Harmonized Heavy-Duty Brake Cycle (WHBC) comprising 246 brake events over 5:39 hours across urban, rural, and motorway segments, defines PM and PN measurement methodologies using gravimetrical and particle number counter methods, specifies hardware requirements including brake dynamometer, enclosure dimensions of 1950 mm length × 1000 mm height × 700 mm depth with divider plate, sampling tunnel with 300 mm fixed inner diameter, and brake temperature measurement by embedded thermocouples, and includes results of preliminary interlaboratory study.

Proposal to amend UN GTR No. 24 by modifying test procedures, definitions, and requirements for brake particle emissions measurement. The amendment introduces improvements including revised definitions (vehicle electrification type, material formulation, pad size), updated measurement tolerances and signal filtering requirements, provisions for brake filtering systems, enhanced specifications for drum and electromechanical brake systems, relaxed cooling airflow adjustment requirements, and a new test cycle for speed-limited vehicles. Documentation of calibration requirements and ongoing quality controls are clarified throughout.

The document authorizes development of a new UN GTR on brake PM and PN emissions from all types of light-duty vehicle brake systems, including validation of the developed novel WLTP-Brake test cycle, investigation and selection of instrumentation and sampling methodology for brake wear particles, definition of minimum requirements for sampling, validation through interlaboratory study, inclusion of regenerative braking, and preparation of the PMP Brake protocol. It also reports on Amendment 2 to UN GTR No. 24 covering laboratory measurement of brake emissions for light-duty vehicles, detailing hardware requirements, test cycle specifications, cooling air conditioning, bedding procedures, and emissions measurement methodologies for particulate matter and particle number.

Proposal to amend Annex 2 – Appendix 1 to add para. 1.4.1. specifying user-selectable mode(s) resulting in the lowest recuperation and relevant pre-test procedures for vehicles with a vehicle specific c-factor according to Annex 5, and to delete items not brake emission related including brake circuit configuration, secondary braking system declaration, brake valve specifications, master cylinder type and size, and booster type and size.