21. The expert from Japan introduced an amendment which addressed unique light trucks available on the Japanese market (ECE/TRANS/WP.29/GRVA/2020/6). The expert of ETRTO proposed a slight modification (GRBP-71-29). GRBP adopted the proposal, as contained in Annex VII, and requested the secretariat to submit it to WP.29 and AC.1 for consideration and vote at their June 2020 sessions Supplement 12 to the 02 series of amendments to UN Regulation No. 117.

14. The expert from ETRTO recalled the postponed proposal for amendments (ECE/TRANS/WP.29/GRVA/2018/5 and GRB-68-12) and presented complementary modifications (ECE/TRANS/WP.29/GRBP/2019/19, GRBP-70-21-Rev.2). Various experts posed clarifying questions, in particular, on the use of terms “repeatability” and “reproducibility”. Following an in-depth discussion, GRBP adopted the proposals, as amended by Annex III, and requested the secretariat to submit them to WP.29 and AC.1 for consideration and vote at their March 2020 sessions as a draft Supplement 11 to the 02 series of amendments to UN Regulation No. 117.

28. The expert of OICA reported on a study with the aim to determine the inter-dependency between the rolling sound, rolling resistance and the main safety performances by carrying out tests according to regulatory or standard procedures (GRBP-70-25). The expert from OICA pointed out, that given the budget constraints, the study had focused on C1 tyres. The study results indicated a conflict between the rolling sound and safety performances, like wet grip, dry grip and lateral aquaplaning. According to the expert, a low level of rolling sound could not be proven as feasible without compromising other parameters essential for vehicle safety and CO2 emission reduction. He added that a full study report would soon be available. Various experts thanked OICA for the study and indicated they would further consider its results. The Chair invited experts to transmit their comments to OICA, if any.

15. GRBP was briefed on the activities of IWG on Wet Grip Performance of Tyres in a Worn State (IWG WGWT) (GRBP-70-23) and noted that IWG WGWT planned to submit an informal document to the seventy-second session of GRBP (September 2020) and a working document for adoption at the seventy-third session (January 2021). GRBP agreed that IWG would be co-chaired by France and the European Commission. The GRBP Chair encouraged all experts to participate in IWG WGWT.

16. The expert of EC proposed enlarging the scope of IWG WGWT to C2/C3 tyres and some further modifications to its Terms of Reference (GRBP-70-03). The experts from France and Japan were of the view out that C1 tyres should remain a priority for IWG WGWT and that C2/C3 tyres should only be addressed afterwards. The experts from the Netherlands and ETRTO pointed out that the behaviour of C2/C3 tyres in a worn state is completely different from C1 tyres. GRBP decided to revert to the issue at the next session and requested IWG WGWT to consider this idea in the interim. GRBP agreed to other modifications to the Terms of Reference, as laid down in Annex IV of the session report.

18. The expert of ETRTO pointed out the need for a new definition of “traction tyres”, because the current definition did not well segregate real traction tyres from non-traction ones (GRBP-70-19). The experts from OICA commented on the document. The Chair invited ETRTO, in cooperation with OICA, to prepare a formal proposal for consideration at the next session.

17. The expert from ETRTO provided an update of tyre industry and ISO activities on improving the wet grip test method for passenger car tyres (C1) (GRBP-70-20) and indicated his intention to submit a working document to the next session of GRBP. The Chair encouraged GRBP experts to send their comments to ETRTO.

15. GRBP was briefed on the activities of IWG on Wet Grip Performance of Tyres in a Worn State (IWG WGWT) (GRBP-70-23) and noted that IWG WGWT planned to submit an informal document to the seventy-second session of GRBP (September 2020) and a working document for adoption at the seventy-third session (January 2021). GRBP agreed that IWG would be co-chaired by France and the European Commission. The GRBP Chair encouraged all experts to participate in IWG WGWT.

16. The expert of EC proposed enlarging the scope of IWG WGWT to C2/C3 tyres and some further modifications to its Terms of Reference (GRBP-70-03). The experts from France and Japan were of the view out that C1 tyres should remain a priority for IWG WGWT and that C2/C3 tyres should only be addressed afterwards. The experts from the Netherlands and ETRTO pointed out that the behaviour of C2/C3 tyres in a worn state is completely different from C1 tyres. GRBP decided to revert to the issue at the next session and requested IWG WGWT to consider this idea in the interim. GRBP agreed to other modifications to the Terms of Reference, as laid down in Annex IV of the session report.

14. The expert from ETRTO recalled the postponed proposal for amendments (ECE/TRANS/WP.29/GRVA/2018/5 and GRB-68-12) and presented complementary modifications (ECE/TRANS/WP.29/GRBP/2019/19, GRBP-70-21-Rev.2). Various experts posed clarifying questions, in particular, on the use of terms “repeatability” and “reproducibility”. Following an in-depth discussion, GRBP adopted the proposals, as amended by Annex III, and requested the secretariat to submit them to WP.29 and AC.1 for consideration and vote at their March 2020 sessions as a draft Supplement 11 to the 02 series of amendments to UN Regulation No. 117.

12. GRBP agreed to postpone consideration of ECE/TRANS/WP.29/GRBP/2019/7 to the next session.

13. On behalf of the group of interested experts (GOIE) on snow tyre provisions, the experts from Germany and ETRTO introduced draft amendments which would allow the type approval of special use tyres that fulfil the requirements for snow performance in Annex 7 (ECE/TRANS/WP.29/GRBP/2019/14). The experts of China, Netherlands, Sweden, Switzerland and OICA raised several questions on the proposed new definitions and limits. The expert from EC made a reservation, because the EU member States should first reach a common position on the proposal which would set up new less stringent limits. The expert of the Russian Federation, being part of GOIE, volunteered to deliver a presentation at the next session with the aim to provide additional explanations. GRBP decided to continue this discussion at the next session.

19. On behalf of the Group Of Interested Experts on snow tyre provisions (GOIE), the expert from Germany reported on their progress (GRBP-71-20). In particular, he proposed establishing a new task force on studded tyres with the objective to draft a new UN Regulation on the approval of studded tyres regarding their snow performance. GRBP endorsed this proposal and noted that the duties of the Chair and Secretary of the task force would be performed by the experts from Finland and ETRTO, respectively.

20. With additional explanations of GOIE (GRBP-71-26), GRBP resumed discussion on the new class of special use tyres intended for use under severe snow conditions (ECE/TRANS/WP.29/GRBP/2019/14). GRBP noted that the proposed new class would provide for better road safety characteristics under severe snow conditions, but with a small increase in the rolling noise. The experts from Germany, Netherlands and Russian Federation supported the proposal. The expert from EC was not in position to agree to the proposal, due to the envisaged higher noise limits which would require modifications of European Union legislation. GRBP decided to revert to this issue at the next session.

33. The expert of OICA briefed GRB about a forthcoming study with the aim to find out if lowering the rolling sound limits would affect other tyre parameters essential for vehicle safety and CO2 reduction (GRB-69-25-Rev.1). GRB took note of this information and invited OICA to report the outcome of the study at the next session.

21. The expert of France proposed a wet adhesion requirement for C1 tyres in a worn state (ECE/TRANS/WP.29/GRB/2019/6 and GRB-69-08). The proposal received comments from ETRTO (GRB-69-10). GRB also noted a recent study on used tyres (GRB-69-09). GRB was of the view that this topic should be pursued in the framework of a new IWG and adopted its Terms of Reference (GRB-69-23), as reproduced in Annex V to the session report. Various experts expressed their willingness to contribute to the activities of the newly established IWG. The experts from France and the European Commission volunteered to act as Chair and Co-Chair, respectively, while ETRTO agreed to provide secretariat support.

22. On behalf of the group of interested experts on snow tyre provisions, the expert from Germany reported on the group’s progress (GRB-69-19) and mentioned that they would submit an official document for consideration at the next session of GRB.

21. The expert of France proposed a wet adhesion requirement for C1 tyres in a worn state (ECE/TRANS/WP.29/GRB/2019/6 and GRB-69-08). The proposal received comments from ETRTO (GRB-69-10). GRB also noted a recent study on used tyres (GRB-69-09). GRB was of the view that this topic should be pursued in the framework of a new IWG and adopted its Terms of Reference (GRB-69-23), as reproduced in Annex V to the session report. Various experts expressed their willingness to contribute to the activities of the newly established IWG. The experts from France and the European Commission volunteered to act as Chair and Co-Chair, respectively, while ETRTO agreed to provide secretariat support.

21. The expert of France proposed a wet adhesion requirement for C1 tyres in a worn state (ECE/TRANS/WP.29/GRB/2019/6 and GRB-69-08). The proposal received comments from ETRTO (GRB-69-10). GRB also noted a recent study on used tyres (GRB-69-09). GRB was of the view that this topic should be pursued in the framework of a new IWG and adopted its Terms of Reference (GRB-69-23), as reproduced in Annex V to the session report. Various experts expressed their willingness to contribute to the activities of the newly established IWG. The experts from France and the European Commission volunteered to act as Chair and Co-Chair, respectively, while ETRTO agreed to provide secretariat support.

21. The expert of France proposed a wet adhesion requirement for C1 tyres in a worn state (ECE/TRANS/WP.29/GRB/2019/6 and GRB-69-08). The proposal received comments from ETRTO (GRB-69-10). GRB also noted a recent study on used tyres (GRB-69-09). GRB was of the view that this topic should be pursued in the framework of a new IWG and adopted its Terms of Reference (GRB-69-23), as reproduced in Annex V to the session report. Various experts expressed their willingness to contribute to the activities of the newly established IWG. The experts from France and the European Commission volunteered to act as Chair and Co-Chair, respectively, while ETRTO agreed to provide secretariat support.