Proposal to replace document ECE/TRANS/WP.29/GRBP/2024/09

Proposal to replace document ECE/TRANS/WP.29/GRBP/2024/07

Proposal to replace document ECE/TRANS/WP.29/GRBP/2024/13

Consolidated version including the amendments proposed with document ECE/TRANS/WP.29/GRBP/2024/13 amended by GRBP-79-24.

Proposal to replace document ECE/TRANS/WP.29/GRBP/2024/03

Consolidated version including the amendments proposed with document ECE/TRANS/WP.29/GRBP/2024/03 amended by GRBP-79-26..

This consolidated document amends and supersedes GRBP/2024/11.

Consolidated version including the amendments proposed with document ECE/TRANS/WP.29/GRBP/2024/11 amended by GRBP-79-28-Rev.1.

ETRTO recommends to create a GRBP GOIE (Group of Interested Experts) involving CP’s
and NGO’s and with the goal to present an Informal Document by GRBP February 2025
session to validate the concept to be followed and implemented in a Working Document
by September 2025

The proposal provides a more clear indication by introducing the definition of “Front axle” so that it clarifies the interpretation of front steering axle.

Addresses a real-life situation that is not considered by current ice grip test conditions: the wet ice (or black ice) conditions.

Proposal for new provisions for the track characterization with additional new text and re-introduces deleted text

Proposal to amend ECE/TRANS/WP.29/GRBP/2025/27

Proposal to supersede the text for a Supplement 22 presented in document GRBP/2026/8.

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.

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.

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.

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 amend paragraph 2.18. to update Standard Reference Test Tyre definitions to ASTM International standards: E1136-19 for SRTT14, F2493-24 for SRTT16, F2872-25 for SRTT16C, F2871-25 for SRTT19.5, F2870-23 for SRTT22.5, F3678-25 for SRTT19.5 siped, and F3677-23 for SRTT22.5 siped. Also amend paragraph 12.21. to accept existing type approvals and grant extensions to class C₃ tyres using either SRTT19.5 or SRTT22.5 before 1 September 2028, and use SRTT19.5 siped or SRTT22.

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.

Proposal to amend GRBP-83-32-Rev.1 to ensure robust tyre abrasion measurements regardless of test method used. Amendments modify paragraph 6.1 to require test facilities demonstrate equivalence per Annex 4 procedure; insert paragraphs 12.8 and 12.9 deeming inter-facility campaign participants equivalent for C₁ tyres and allowing pre-regulation test data through 1 July 2028; insert Annex 3 paragraph 1.4 requiring inter-facility equivalence assessment; amend Annex 3 paragraph 2.8 with abrasion calculation equations including transfer function coefficient; insert test report items 1.1–1.4 in Appendices 2 and 6; and insert new Annex 4 establishing equivalence demonstration procedure for vehicle and indoor drum test facilities.

ETRTO comments on EC/JRC compromise proposal for Annex 4 tyre abrasion. ETRTO proposes an ALI range minimum of 0.5 as feasible and consistent with statistical distribution in MA results, rejecting the 0.7 range as unrealistic. For Generic Transfer Function gain, ETRTO recommends retaining a = 1.38 rather than the revised a = 1.45, to minimize rejection of good vehicle test results. ETRTO requests TFTA ToR amendment to confirm these conditions by February 2027 based on TA-45-9.