Minutes of the 50th session of TFTA held on 6 July 2026. TFTA approved previous meeting minutes and agenda. The SWG Secretary updated on workplan 2026 organizational matters. ETRTO reported two best practice sessions on open road convoy method on 26 June and 3 July, with JATMA organizing a drum method session on 7 July. JASIC provided comments on the UTAC timeline Gantt; TFTA agreed to simplify subject lines 13-15, keep the February 2027 timeline with a review note after summer 2026, and retain line 24 with an indicative note. Action items assigned include preparing a revised Gantt and contacting test facilities on tread depth measurements. Discussion covered C1 mileage potential metric development, C2 test method status and equivalence framework for C2 tyres, and C3 test method development with a brainstorming workshop planned for 8-9 October in hybrid format. TFTA agreed to prepare Supplement 1 to UN Regulation No. 186 with submission deadline week of 9 November 2026.

Study evaluating the validity of the current recommendation in Annex 3 Appendix 5 for sandpaper surface replacement interval based on running distance by examining test results exceeding 20,000 km. Testing nine consecutive runs on #80 grit sandpaper without replacement over 45,000 km total distance using new tyres for each run. Surface roughness measured by MPD and micro roughness showed no significant change and satisfied requirements in Paragraph 2.4.2.3. SRTT17S abrasion level remained above specification limits. Reproducibility of Abrasion Index was maintained when compared with Market Assessment results. Proposes extending replacement interval from 20,000 km to 30,000 km for 2-position drums and from 40,000 km to 60,000 km for 1-position drums.

Minutes from the Task Force on Tyre Abrasion 53rd session held 29 October 2026. The session reviewed TADG status on drafting C1 and C2 provisions for GRBP Working Document 85th session and discussed amendment proposals to UN R186. TFTA agreed with TADG proposals including removal of special use tyres from AICT requirements, keeping drum abrasion level range as currently defined, and placing sandpaper surface replacement recommendation frequency in square brackets. TFTA also agreed with ETRTO proposals for C1 vehicle method amendments to paragraphs 1.6.2, 1.6.8, 1.6.9, 1.6.4.1, 1.7.4.1, and 7.4, and for C2 vehicle method amendments to paragraphs 1.9.2, 1.6.2, 1.10.4.2, 1.8.2.1, 1.8.2.2, and 1.6.4. GRPE endorsed the request to elevate TFTA to an IWG TA and address the request to WP.29 session 200 in November 2026.