Minutes of a PMP hybrid session held 12 October 2026 at the Palais des Nations in Geneva. Discussion covered amendments to GTR 24 and UN R179 on heavy-duty brake emissions, including new limits for 2030, C-factor measurements, driving modes, brake functions, emission factor calculations, and compliance and conformity of production procedures. Topics included measurement setup, payload factor, test inertia determination methods, inter-laboratory study status with data from 5 labs, and removal of square brackets from GTR text. The group reviewed brake particle emission work from Phase 2 of the DfT programme and preliminary results from a calibration materials inter-laboratory exercise involving 8 labs, recommending continued use of emery oil for annual validation at 23 nm.

Meeting minutes documenting PMP discussions on amendments to Brakes GTR 24 and UN R179, including TF3a layout and testing topics, TF3b vehicles limited speed work, TF3c brake replacement parts with a new UNR to be introduced, and TF4 electromechanical brakes with no further progress. GTR and UNR informal documents on HD brakes were presented with trailers removed from scope, open points on PM Emission Factor units, caliper position, test input parameters, and cooling air flow value addressed, and a 3-month delay in round robin testing reported.

Final status report on development of a new UN Global Technical Regulation addressing particle matter (PM) and particle number (PN) emissions from heavy-duty vehicle brake systems. The GTR introduces brake emissions groups based on design and performance characteristics, establishes test parameters for disc and drum brakes across five diameter groups, defines the World Harmonized Heavy-Duty Brake Cycle (WHBC) comprising 246 brake events over 5:39 hours, specifies brake dynamometer hardware requirements with enclosure dimensions of 1950 mm length, 1000 mm height, and 700 mm depth, requires PM10 and PM2.5 gravimetric measurement and particle number counting, and prescribes a friction braking share coefficient (c-factor) of 1 pending availability of additional data. A preliminary interlaboratory study confirms test cycle reproducibility and particle measurement repeatability, with recommendations to specify fixed enclosure and duct dimensions for improved cross-laboratory consistency.

Overview of documents and working party activities for the 95th session of the Working Party on Pollution and Energy (GRPE). Documents address improvements to UN R179 (Laboratory Measurement of Brake Emissions for Light Duty Vehicles) including handling of vehicles with limited speed, brake replacement parts regulation, and GTR 24 (Measurement procedures for Brake corner emission factors). Related documents also cover a new regulation for heavy-duty brake emissions and a new global technical regulation for heavy-duty brakes. Working documents ECE/TRANS/WP.29/GRPE/2026/29, ECE/TRANS/WP.29/GRPE/2026/30, ECE/TRANS/WP.29/GRPE/2026/31, ECE/TRANS/WP.29/GRPE/2026/32, and ECE/TRANS/WP.29/GRPE/2026/53 are submitted.

Document presents preliminary views on minimum performance requirements for in-vehicle battery durability under Euro 7 heavy-duty vehicle standards. It outlines implementation timeline for the OMNIBUS proposal in first and second phases, with application dates of 1 January 2030 for the first phase and 1 January 2035 for the second phase. Brake emissions and tyre abrasion requirements are addressed, including UN Regulation No. 186 application dates for C2 and C3 class tyres. Reporting and review provisions under Article 18 are included. The document notes that the order of items and timeline indications are preliminary and for discussion purposes only.

Presentation on brake inertia determination for potential amendment to heavy-duty brake emission protocol. Currently proposed protocol assumes test inertia determined based on UN R90, but comparison with C-factor from vehicle testing showed significant differences in inertia and actual load during dynamometer testing, with front and rear values differing by up to 2.3 times. Proposes retaining UN R90-based approach as default method while adding alternative inertia determination method considering vehicle mass and multi-axle configurations. Analysis of 43 Japanese market vehicle models showed UN R90-based approach can result in brake loads ranging from 0.1 to 5.7 times those of vehicle-based approach.

Proposal to amend GRPE/2026/29, establishing a globally harmonized laboratory methodology for measuring brake particulate matter (PM) and particle number (PN) emissions from heavy-duty vehicles of categories M₂, M₃, N₂, N₃, and O₃, O₄.

Proposal to establish a new UN Regulation on laboratory measurement of brake emissions for heavy-duty vehicles of categories M₂, M₃, N₂ and N₃ using friction braking. The regulation defines test procedures, brake emissions groups, compliance requirements with emission limits for PM10 and SPN10, type approval processes, conformity of production requirements with statistical sampling procedures, and technical specifications for test systems including brake dynamometers, brake enclosures, sampling tunnels, and particle measurement instrumentation.

Provisional agenda for the 57th meeting of the Informal Working Group on DETA scheduled for 13 November 2026. Topics include approval of the agenda and draft minutes from the 56th session, state of play, new DETA software version, widening DETA scope, potential use of DETA for sharing technical information in the context of a proposed GRPE UN Regulation on brake emission of non-original parts, adding an attribute in DETA to indicate the latest series of amendments of approvals, and a potential update of the IWG’s Terms of Reference.

Progress report on development of a Global Technical Regulation for brake emissions testing. The document presents bracketed parameters under development including brake test temperature measurement, sampling plane positioning, brake enclosure dimensions, payload factors, and emission factor calculations. It outlines the structure of the informal document based on UN R179, defines endurance braking systems and electric regenerative braking, presents C-factor methodology for primary and secondary endurance braking, and describes conformity of production procedures and next steps including removal of brackets and round-robin data analysis.

Overview of working documents for the 95th session of GRPE, listing five working documents on new GTR for heavy-duty brake emission, UN R179 second supplement, GTR 24 third amendment, vehicles with limited speed for UN R179 and GTR 24, and new UNR on emissions covering brake replacement parts, with informal documents to follow from clean working documents.

Agenda for a PMP webex meeting on 29 September 2026 to review meeting minutes, overview amendments to GTR 24 and UN R179 on brakes across multiple task forces covering layout and testing topics, vehicles limited speed, brake replacement parts, and electromechanical brakes, discuss GTR and UN R heavy-duty brakes, and address any other business.

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.

Task Force 5 progressed toward GTR adoption planned for GRPE 95th session in 10/2026. JRC endurance braking tests conclude 07/08/2026. A small round robin exercise with six participants tests three airflow settings to finalize bracketed values. Key updates include maximum sampling probe length of 1.35m, PM10 probe positioning on outside streamline for bent layouts, and probe distance reduction from 100mm to 70mm. Proposal to delete the Disc or Drum Metallurgy for Brake Groups section. Final GTR text requires PMP comments by 22/07/2026, with layout decisions by 16/07/2026. UNR drafting based on UN R179 skeleton has commenced with significant work required.

Draft Minutes of the 56th Particle Measurement Programme session held online on 9th July 2026, 12:00-14:30 CET. The meeting reviewed amendments to Brakes GTR 24 and UN R179 across five task forces. TF3a presented layout and testing topics with concerns raised regarding repetition increases and force distribution. TF3b discussed vehicles with limited speed and family classification issues. TF3c addressed brake replacement parts and emission limits. TF4 reported on electromechanical brakes with work package B agreed. TF5 presented the GTR on heavy-duty brake particle emissions with results expressed in mg/km, with some points remaining in brackets pending inter-laboratory comparisons. Comments are due by 16th July, with the next meeting expected mid/end of September 2026 and a hybrid PMP meeting planned for 12th or 13th October in Geneva.

This document proposes a new UN Global Technical Regulation (UN GTR) for measuring brake particle emissions from Heavy-Duty Vehicles (HDVs). The GTR establishes a harmonised laboratory methodology covering the Worldwide Harmonised Heavy-Duty Vehicles Brake Cycle (WHBC), test system requirements, and measurement protocols for particulate matter (PM) and particle number (PN) emissions.

Key substantive elements include:

- Scope covering M₂–M₃, N₂–N₃, and O₃–O₄ category vehicles with friction braking systems
- Detailed specifications for brake dynamometer systems, enclosure design, sampling tunnel geometry, and cooling air conditioning
- Definition of the WHBC comprising three segments (urban, rural, motorway) with 246 brake events over 20,353 seconds and 271 km
- Brake bedding procedure (six consecutive WHBC cycles) followed by a single WHBC emissions measurement section
- Requirements for PM₁₀ and PM_2.5 gravimetric sampling using cyclonic separators and filter-based collection
- Requirements for TPN₁₀ and SPN₁₀ measurement using dilution systems and particle number counters with specified PCRFs
- Detailed quality checks including speed violations, brake event count verification, and kinetic energy dissipation tolerances
- Comprehensive calibration requirements for dynamometer, flow measurement, weighing equipment, and sampling/measurement devices
- Test output specifications including Event-Based, Time-Based, Mass Measurement, and Test Report files

The regulation applies a friction braking share coefficient to convert reference emission factors from the tested brake to final emission factors applicable to the vehicle.

PMP webex meeting scheduled for 9th July 2026, 12:00–14:30 CET. Agenda includes an overview of amendments to Brakes GTR 24 and UN R179, task force discussions on layout and testing topics, vehicles limited speed, brake replacement parts, electromechanical brakes GTR and UNR, HD brakes, projects on tyres and brakes, and any other business. Webex meeting access details and link provided.

The 56th PMP session convened online on 7 May 2026 with approximately 70 participants. Meeting minutes from 13 March 2026 were accepted. PMP agreed on a joint neutral template for all task forces. TF3a discussed cooling air adjustment, temperature criteria, and vehicle emission factors, with proposals requested by end of May 2026. TF3b will discuss family building and speed-limited vehicles. TF3c presented brake replacement parts activities. TF4 prepared work package B on electromechanical brakes and requested feedback by end of May 2026. TF5 reported progress on GTR on HD brake particle emissions with test campaigns planned. The next meeting is expected end of June or beginning of July 2026.