Wet Grip on Worn Tyres (WT)
Reports to GRBP

This group was authorized in 2019 to consider the performance of tyres after initial use. The broad concern is to ensure that somewhat worn tyres continue to comply with the requirements for new tyre approvals (i.e., no serious degradation in performance after initial use and before such wear as would require tyre replacement).

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Meetings (77) Documents Regulations ← Back
Documents 2022
12 Jan 2022 Agenda for the 32nd Worn Tyres task force session WT-32-01/Rev.1
12 Jan 2022 Worn Tyre Post Processing task force status report WT-32-02
12 Jan 2022 Worn Tyres: JASIC Review on ETRTO Proposed Equations WT-32-03
12 Jan 2022 EU Tyre Industry proposal for Wet grip on Worn tyres (C1) WT-32-04
12 Jan 2022 Worn Tyres: Timeline proposal for additional test campaign WT-32-05
13 Jan 2022 Attendance list from the 32nd Worn Tyres working group session WT-32-06
18 Jan 2022 Agenda for the 33rd Worn Tyres working group session WT-33-01
19 Jan 2022 Worn tyres: Comments on threshold proposal and timeline for additional assessment WT-33-04
19 Jan 2022 Report of the 32nd Worn Tyres working group session WT-32-06/Rev.1
19 Jan 2022 Worn tyres: Proposal for additional test campaign timeline WT-33-03
19 Jan 2022 Worn tyres: Proposal for C1 wet-grip threshold WT-33-02
25 Jan 2022 Attendance list from the 33rd Worn Tyres informal group session WT-33-05
25 Jan 2022 Minutes from the 33rd Worn Tyres informal group session WT-33-06
25 Jan 2022 Worn tyre wet grip threshold provisions pursuant to the 33rd Worn Tyres informal group session WT-33-07
26 Jan 2022 Agenda for the 34th Worn Tyres informal group session WT-34-01/Rev.1
26 Jan 2022 Status report from the Worn Tyres Post-Processing task force WT-34-02
26 Jan 2022 UN R117: Draft amendments to document WP.29/2022/11 on worn tyres WT-34-03
26 Jan 2022 Threshold proposal for C1 wet grip of worn tyres (Revision 2) WT-34-04
26 Jan 2022 Proposal for worn tyre track friction range WT-34-05
27 Jan 2022 UN R117: Proposal to amend document WP.29/2022/11 on worn tyres WT-34-06
1 Feb 2022 Tender for a study on wet grip of worn tyres WT-35-02
2 Feb 2022 Agenda for the 35th Worn Tyres informal group session WT-35-01/Rev.1
2 Feb 2022 Concept proposal for C2 and C3 worn tyres wet grip WT-35-03
2 Feb 2022 Input on C1 tyre track friction range WT-35-04
4 Feb 2022 UN R117: Proposal to amend document GRBP/2022/11 on worn tyres WT-35-06
4 Feb 2022 UN R117: Concept proposal for addressing C2 and C3 worn tyres wet grip WT-35-07
4 Feb 2022 Attendance list from the 35th Worn Tyres working group session WT-35-08
4 Feb 2022 Report from the 35th Worn Tyres working group session WT-35-11
4 Feb 2022 Worn Tyres working group status report to GRBP-75 WT-35-09
4 Feb 2022 Proposal for revised Worn Tyres working group terms of reference WT-35-10
4 Feb 2022 Position on worn tyre track friction properties WT-35-05
1 Mar 2022 Agenda for the 36th Worn Tyres working group session WT-36-01
1 Mar 2022 Worn tyres: Data collection compilation SRTT 2mm WT-36-02/Rev.2
4 Mar 2022 Worn tyres: Evaluation of Molded SRTT-worn WT-36-03
8 Mar 2022 Worn Tyres working group work plan WT-36-04
8 Mar 2022 Attendance list from the 36th Worn Tyres working group session WT-36-05
8 Mar 2022 Report of the 36th Worn Tyres working group session WT-36-06
5 Apr 2022 Agenda for the 37th Worn Tyres working group session WT-37-01/Rev.1
5 Apr 2022 Worn WGI C1 tyre cluster definition proposals for UHP, Legal Race and All Terrain WT-37-02
5 Apr 2022 Worn tyres: C2 and C3 regulatory text proposal WT-37-03
18 Apr 2022 Agenda for the supplemental session to the 37th Worn Tyres working group session WT-37-01
18 Apr 2022 Japan comments on worn tyre cluster definitions WT-37-02
18 Apr 2022 Minutes of the 37th Worn Tyres working group session WT-37-05
18 Apr 2022 Attendance list from the 37th Worn Tyres working group session WT-37-04
21 Apr 2022 Attendance list from the supplemental meeting of the 37th Worn Tyres working group session WT-37-03
21 Apr 2022 Minutes of the supplemental meeting of the 37th Worn Tyres working group session WT-37-05
21 Apr 2022 Updated work plan of the Worn Tyres working group WT-37-04
25 Apr 2022 Agenda for the 28th Worn Tyres working group WT-38-01
29 Apr 2022 Minutes from the 38th Worn Tyres working group session WT-38-04
29 Apr 2022 Updated work plan for the Worn Tyres working group WT-38-03
2 May 2022 Attendance list from the 38th Worn Tyres working group session WT-38-02/Rev.1
13 May 2022 Agenda for the 39th Worn Tyres working group session WT-39-01
13 May 2022 Worn tyres cluster definition and threshold WT-39-02
13 May 2022 Threshold proposal for C2 and C3 tyres wet grip in worn state WT-39-03
19 May 2022 Attendance list from the 39th Worn Tyres working group session WT-39-04
19 May 2022 Report from the 39th Worn Tyres working group session WT-39-05
23 May 2022 UN R117: Worn Tyres drafting group proposal for C1-C2-C3 tyres (04 series of amendments) WT-40-02
23 May 2022 UN R117: Proposal for Standard Reference Test Tyre (SRTT) in worn state WT-40-03
25 May 2022 Agenda for the 40th Worn Tyres working group session WT-40-01/Rev.1
25 May 2022 Proposal for C2/C3 tyre wet grip in worn state WT-40-04
1 Jun 2022 Minutes from the 40th Worn Tyres working group session WT-40-06
1 Jun 2022 Attendance list from the 40th Worn Tyres working group session WT-40-05
3 Jun 2022 UN R117: Proposal to add tread depth measurement prescriptions in Annex 9 WT-41-02
7 Jun 2022 Agenda for the 41st Worn Tyres working group session WT-41-01
8 Jun 2022 UN R117: Draft proposal for 04 series of amendments on C1, C2, and C3 tyres WT-41-03/Rev.1
8 Jun 2022 UN R117: Consolidated drafting group proposal for Supplement 1 to the 03 series of amendments WT-41-04/Rev.1
9 Jun 2022 Worn tyres: C1 cluster definition and threshold proposals for “UHP” and “All Terrain” WT-41-05/Rev.1
9 Jun 2022 Attendance list from the 41st Worn Tyres working group session WT-41-06
9 Jun 2022 Minutes from the 41st Worn Tyres working group session WT-41-07
10 Jun 2022 Agenda for the 42nd Worn Tyres working group session WT-42-01
10 Jun 2022 UN R117: Draft text for 03 series Supplement 3 include tread depth measurement WT-42-02
10 Jun 2022 UN R117: Draft text for 04 series amendments on worn C1, C2, and C3 tyres WT-42-03
10 Jun 2022 Attendance list from the 42nd Worn Tyres working group session WT-42-04
10 Jun 2022 Minutes from the 42nd Worn Tyres working group session WT-42-05
30 Jun 2022 Worn Tyres Post-Processing subgroup status report WT-43-02
4 Jul 2022 Agenda for the 43rd Worn Tyres working group session WT-43-01
7 Jul 2022 Worn tyres: Standard reference test tyre data collection compilation WT-43-05
7 Jul 2022 Minutes of the 43rd Worn Tyres working group session WT-43-03
7 Jul 2022 Attendance list from the 43rd Worn Tyres working group session WT-43-04
12 Jul 2022 Worn tyres: Proposal for 2023 additional test campaign matrix WT-44-01
20 Jul 2022 Agenda for the 44th Worn Tyres working group session WT-44-02
20 Jul 2022 Small group discussion on usage purpose clustering WT-44-04
26 Jul 2022 Worn tyres: Comments on proposal for 2023 additional test campaign work plan WT-44-03
27 Jul 2022 UN R117: Draft text for informal document to amend document GRBP/2022/22 WT-44-05/Rev.1
27 Jul 2022 UN R117: Draft text for an informal document to amend document GRBP/2022/23 WT-44-06/Rev.1
27 Jul 2022 Attendance list from the 44th Worn Tyres working group session WT-44-10
27 Jul 2022 Worn tyres: Proposal for additional test campaign WT-44-07
28 Jul 2022 Worn Tyres working group status report to GRBP WT-44-08
28 Jul 2022 Minutes of the 44th Worn Tyres working group WT-44-09
5 Sep 2022 Draft agenda for the 45th Worn Tyres working group session WT-45-01
12 Sep 2022 ETRTO workplan proposal for Wet Grip on Worn tyre test precision improvement WT-45-02
13 Sep 2022 Worn tyre wet test precision improvement test plan proposal WT-45-03
14 Sep 2022 Participants list from the 45th Worn Tyres working group session WT-45-05
14 Sep 2022 Minutes of the 45th Worn Tyres working group session WT-45-04
13 Oct 2022 Agenda for the 46th Worn Tyres working group session WT-46-01/Rev.1
13 Oct 2022 Worn tyre wet test precision improvement: test plan proposal WT-46-02
13 Oct 2022 Worn tyres: 2023 test campaign-report on JASIC/JATMA-ETRTO meetings WT-46-03
16 Oct 2022 Participation list from the 46th Worn Tyres working group session WT-46-04
16 Oct 2022 Minutes from the 46th Worn Tyres working session WT-46-05
28 Oct 2022 Agenda for the 47th Worn Tyres working group session WT-47-01
4 Nov 2022 Worn tyres work plan proposal WT-47-02
9 Nov 2022 Worn Tyres working group: Draft updated terms of reference WT-47-03/Rev.3
9 Nov 2022 UN R117: Draft text for a 03 series of amendments on wet grip of worn tyres WT-47-04
9 Nov 2022 Minutes from the 47th Worn Tyres working group session WT-47-05
9 Nov 2022 Attendance list from the 47th Worn Tyres working group session WT-47-06
10 Dec 2022 Agenda for the 48th Worn Tyres working group session WT-48-01/Rev.1
12 Dec 2022 Status report of the Worn Tyres working group small group activities WT-48-02
16 Dec 2022 Participants list from the 48th Worn Tyres working group session WT-48-04
21 Dec 2022 Minutes from the 48th Worn Tyres working group session WT-48-03