Proposal superseding GRBP/2026/7 to amend paragraph 1. of UN R75 to restructure the scope provision, clarifying that the Regulation applies to new pneumatic tyres designed primarily for vehicles of category L₁, and to exclude approvals for tyre types designed exclusively for “off road” use marked “NHS”, for competitions, and for bicycle rims according to ISO 5775-2:2021.

ETRTO measurement uncertainties reduction efforts for UN R117 rolling sound emission test methods are progressing through outdoor and indoor Round Robin tests. Eight of thirteen outdoor test centres have completed tests for C₁ and C₂ tyres; remaining centres anticipate completion by mid-year. Indoors, two of six ETRTO test centres completed tests with others expected finished by mid-year. An intermediate report with available data will be presented in September 2026, full results postponed to February 2027, and the Working Document with test method evolution now expected in September 2027 instead of February 2027.

Proposal to amend GRBP/2025/27 based on GRBP-83-32. Modifications to Annex 3 revise the abrasion index calculation methods for both vehicle test and indoor drum test methods. The abrasion margin (Amargin) is redefined in two stages accounting for evolution of measurement methods and tyre technology, with different values for normal, snow, and special use tyre categories. Amargin allowances for specific tyre groups, including severe snow conditions tyres, reinforced tyres, and tyres with nominal aspect ratio ≤40, are defined as cumulative additions to the base Amargin value.

ETRTO presents a temporary conservative transfer function for tyre abrasion testing with a gain value of 1.5, designed to minimize drum inversion risk and reduce rejection risk while enabling coexistence of Indoor Drum Method and Outdoor Vehicle method at GRBP 83rd session. The transfer function, based on TA-40-2 data analysis, will be revised following a 2026 workplan before a more relevant solution in Supplement 1 to UNRxxx at GRBP 84th session.

Proposal to supersede GRBP/2025/28, consolidating amendment proposals from GRBP/2025/28, GRBP-82-27, GRBP/2026/6, and GRBP-83-20-Rev.2. Changes include moving tyre abrasion provisions to a separate UN Regulation, deleting paragraphs 5.7 to 5.10 and Annex 10, updating ASTM standard references to F2872-25, F2871-25, and F3678-25, amending Annex 5 part (b) paragraph 1.1.1., and deleting paragraph 2.21. defining abrasion performance terms.

ETRTO presents its position on remaining open points for C₁ tyre abrasion limit settings, reminding positions from GRBP-82-24. Key points include: inclusion of two assessment methods; limit settings proposing approximately 23% market removal by Euro7 application timeline and additional 13.5% removal five years later; exclusion of C₁ special use tyres representing 0.7% of EU market; retention of 0.1 allowance for Extra Load tyres and tyres with nominal aspect ratio 40 suitable for speeds 300 km/h representing 7.2% of market. ETRTO views this as a challenging compromise package respecting political expectations and industry effort.

Proposal to establish a list of test facilities deemed equivalent pursuant to paragraph 12.8 of the draft UN Regulation on tyre abrasion. The list recognizes six foundational facilities that participated in the initial inter-facility campaign to develop abrasion limits for C₁ tyres. The facilities are: DEKRA Test Center SA (France, circuit); IFV (Germany, circuit); Link Engineering Company GmbH (Germany, circuit); Bridgestone Corporation (Japan, indoor drum); Sumitomo Rubber Industries, LTD. (Japan, indoor drum); and The Yokohama Rubber Co., Ltd. (Japan, indoor drum). These facilities generated foundational data used to define abrasion limits and are deemed equivalent for equivalence procedures under Annex 4.

Proposal to amend Annex 5, part (B) of UN R117. Changes include replacing “Average Deceleration (AD)” with “braking force coefficient (BFC)” terminology throughout paragraphs 2.2.2.1., 2.2.2.7.1., 2.2.2.7.2., and 2.2.2.7.3. Paragraph 2.2.2.3. is amended to clarify terminology regarding vertical static test load and load capacity. Paragraph 2.2.2.7.4. is deleted. Paragraphs 2.2.2.7.5. through 2.2.2.8.4. are renumbered and amended to align the wet grip test method for C2 and C3 tyres with changes made to the passenger car test method and ISO 15222:2025.

The document establishes procedures for demonstrating equivalence between vehicle circuit and indoor drum test facilities. It defines requirements for selecting exercise tyres and participating facilities, establishing baseline values from multiple facilities, and comparing facility results against baselines. For indoor drum facilities, transfer functions mathematically relate drum results to vehicle results, either as generic (fixed coefficient) or specific (facility-determined coefficient). Facilities must meet statistical criteria including result deviation limits and root mean square deviation thresholds to demonstrate equivalence.