1. The Working Party on Noise and Tyres (GRBP) held its seventy-eighth session from 30 August to 1 September 2023 in Geneva. The meeting was chaired by Mr. S. Ficheux (France). Experts from the following countries participated in the work following Rule 1(a) of the Rules of Procedure of the World Forum for Harmonization of Vehicle Regulations (WP.29) (TRANS/WP.29/690/Rev.2): Australia, Canada, China, Czechia, Finland, France, Germany, India, Italy, Japan, Netherlands, Norway, Republic of Korea, Russian Federation, Saudi Arabia, South Africa, Spain, Sweden, Switzerland and United Kingdom of Great Britain and Northern Ireland. Experts from the European Commission participated. Experts from the following non-governmental organizations also participated: American Automotive Policy Council (AAPC), Bureau International Permanent des Associations de Vendeurs et Rechapeurs de pneumatiques (BIPAVER), International Motor Vehicle Inspection Committee (CITA), European Association of Automotive Suppliers (CLEPA), European Garage Equipment Association (EGEA), European Tyre and Rim Technical Organization (ETRTO), Imported Tyre Manufacturers Association (ITMA), International Motorcycle Manufacturers Association (IMMA), International Organization for Standardization (ISO), International Organization of Motor Vehicle Manufacturers (OICA) and World Blind Union (WBU).

2. GRBP considered and adopted the agenda (ECE/TRANS/WP.29/GRBP/2023/13, as amended by GRBP-78-01). GRBP noted the running order proposed by the Chair (GRBP-78-23). The informal documents are listed in annex I to the session report. The GRBP informal groups are given in annex IV.

GRBP-78-01 | GRBP: Updates to the agenda of the 78th (August 2023) session

GRBP-78-23 | GRBP: Running order of the agenda for the 78th (August 2023) session

GRBP/2023/13 | GRBP: Annotated provisional agenda for the 78th (Aug-Sep 2023) session

3. The experts from IMMA and ISO tabled amendments that allowed the use of the latest standard ISO 10844:2021 test track (ECE/TRANS/WP.29/GRBP/2023/14, ECE/TRANS/WP.29/GRBP/2023/15). The expert from France proposed to complement these amendments with the phasing out of ISO 10844:2014 compliant test track (GRBP-78-19). GRBP invited IMMA and ISO to revise their proposal for consideration at the next session.

GRBP-78-19 | UN R41 and R63: Proposal to amend documents GRBP/2023/14, 15, and 16 Proposal to transition test facilities from ISO 10844:2014 to ISO 10844:2021 by January 2029.

GRBP/2023/14 | UN R41: Proposal for Supplement 11 to the 04 series of amendments Proposal to allow using the state-of-the-art test track from the latest standard ISO 10844:2021.

GRBP/2023/15 | UN R41: Proposal for Supplement 3 to the 05 series of amendments Proposal to allow using the state-of-the-art test track from the latest standard ISO 10844:202

GRBP/2023/16 | UN R63: Proposal for Supplement 6 to the 02 series of amendments Proposal to allow using the state-of-the-art test track from the latest standard ISO 10844:2021.

4. The expert from the Informal Working Group on Measurement Uncertainties (IWG MU) reported on their activities (GRBP-78-09).

GRBP-78-09 | Measurement Uncertainties: Status report of the informal group

5. The experts of IWG MU introduced a new draft document for reference on measurement uncertainties which addressed UN Regulations Nos. 51 and 117 as a first step (GRBP-78-07). The experts from France and the United Kingdom posed questions, while the experts from Germany and the Netherlands pointed out a large test track uncertainty. The Chair invited IWG MU to liaise with the above experts with the aim to prepare a revised document for the next session.

GRBP-78-07 | Measurement Uncertainties when Testing in WP.29 GRBP Vehicle Regulations Proposal for a reference document concerning a general approach for how to handle measurement uncertainties under UN Regulations within the purview of GRBP.

6. The experts of IWG MU presented a proposal for amendments to the Consolidated Resolution on the Construction of Vehicles (R.E.3) (GRBP-78-08). The experts from France, Germany, Netherlands, Switzerland and the United Kingdom commented on the proposal. In view of these comments and of the need to consult with the Working Party on General Safety Provisions (GRSG), GRBP agreed to revert to GRBP-78-08 at its next session.

GRBP-78-08 | RE3: Proposal for a Supplement 1 to Revision 7 Proposal from the informal group on Measurement Uncertainties to introduce provisions on exterior noise measurements when performing type-approval, COP or, field testing (e.g., market surveillance).

7. The expert of the Informal Working Group on Additional Sound Emission Provisions (IWG RD-ASEP) presented their status report (GRBP-78-14) and the updated Terms of Reference (GRBP-78-13). GRBP agreed to rename IWG to the Informal Working Group on Real Driving – Additional Sound Emission Provisions (IWG RD – ASEP) and adopted its Terms of Reference, as contained in annex II to the session report.

GRBP-78-13 | RD-ASEP: Proposal for Terms of Reference of the Informal Working Group on Real Driving-Additional Sound Emission Provisions

GRBP-78-14 | ASEP: Status report of the informal working group

8. GRBP took note of an interim report on the ongoing ASEP/ RD-ASEP study presented by OICA (GRBP-78-34).

9. GRBP was informed that the Task Force on Quiet Road Transport Vehicles (TF QRTV) had identified the need that UN Regulation No. 51 regulate noise emissions of Battery Electric Vehicles (BEVs) with sound enhancement systems other than the Acoustic Vehicle Alerting System (AVAS) of UN Regulation No. 138. The expert from OICA presented a first draft of amendments to UN Regulation No. 51 to address this issue (GRBP-78-10).

10. GRBP expressed concerns about aftermarket products that create artificial noise of BEVs other than for safety purposes, and generally supported the idea to eliminate a “grey area” between UN Regulations Nos. 51 and 138. GRBP noted that OICA would prepare a revised document for BEVs with AVAS.

GRBP-78-10 | UN R51: Proposal for a supplement to the 03 series of amendments This proposal concerns to amendments to Annex 7. The proposed changes regarding sound enhancement systems are based on the 03 series of amendment up to Supplement 9. In addition, some clarifications concerning power definition and temperature correction have been included based on experiences with the last changes of this regulation.

11. GRBP recalled the concerns of paragraph 3 above and invited IMMA and ISO to submit a revised document for consideration at the next session.

GRBP-78-19 | UN R41 and R63: Proposal to amend documents GRBP/2023/14, 15, and 16 Proposal to transition test facilities from ISO 10844:2014 to ISO 10844:2021 by January 2029.

GRBP/2023/16 | UN R63: Proposal for Supplement 6 to the 02 series of amendments Proposal to allow using the state-of-the-art test track from the latest standard ISO 10844:2021.

12. The expert from IMMA presented a draft document for reference with the industry guidelines on antitampering provisions for Non-Original Replacement Exhaust Systems (NORESS) (ECE/TRANS/WP.29/GRBP/2023/17). Various experts were in support of the guidelines and stressed the need for regular updating in the future. GRBP adopted the document and requested the secretariat to issue it as a document of reference on the dedicated webpage. As a next step, GRBP agreed to study the possibility of integrating the guidelines, in a suitable language, into UN Regulation No. 92.

GRBP/2023/17 | UN R92: Proposal for a reference document Proposal to provide industry guidelines on anti-tampering provisions for Non-Original Replacement Exhaust Silencing Systems (NORESS) in UN Regulation No. 92.

13. The expert of TF QRTV reported on their activities (GRBP-78-11) and stressed that the Task Force strived to find a balance between safety and environmental aspects. GRBP also took note of a draft consolidated version of UN Regulation No. 138 prepared by TF QRTV (GRBP-78-12).

14. The representatives of WBU briefed GRBP on their position regarding QRTV (GRBP-78-21), in particular the need to ensure the AVAS sound emission when the vehicle is stationary and up to 32 km/h, to ensure the safety of blind people.

15. For the AVAS stationary sound, which was optional in the current text of UN Regulation No. 138, the expert of TF QRTV clarified that the Task Force was considering that sound should not be allowed at standstill for the “P” position of automatic transmission, while for the “D” and “R” positions, discussion was ongoing.

16. Several experts expressed concerns about the environmental impact of stationary noise and wondered whether the widely used start/stop system posed any security risks. Some others reported on accidents due to the absence of a stationary AVAS sound.

17. GRBP stressed the importance of further discussions within TF QRTV and supported their efforts to find a reasonable compromise. GRBP also urged all experts to participate in this work.

GRBP-78-11 | QRTV: Status report of the informal group Status report of the task force on the 02 series of UN R138.

GRBP-78-12 | UN R138: Consolidated text Consolidated text prepared by the QRTV task force (for information).

GRBP-78-21 | UN R138: Comments on Specific Aspects of the Acoustic Vehicle Alerting Sound Comments concerning:<ul><li>AVAS Pause Switch</li><li>AVAS Sound Pressure Levels</li><li>Maximum AVAS Sound Pressure Level</li><li>AVAS Sound when vehicle stationary</li></ol>

18. The expert from France presented a proposal that specified a tolerance for the maximum overall width of tyres identified by the “tyre to rim fitment configuration” symbol A (ECE/TRANS/WP.29/GRBP/2023/18, GRBP-78-20-Rev.1). GRBP adopted the proposal and requested the secretariat to submit it for consideration and vote at the March 2024 sessions of WP.29 and the Administrative Committee (AC.1) as draft Supplement 27 to UN Regulation No. 54.

GRBP-78-20/Rev.1 | UN R54: Additional justification to support document GRBP/2023/18

GRBP/2023/18 | UN R54: Proposal for Supplement 27 Proposal to specify explicitly that the maximum overall width of tyres identified by the “tyre to rim fitment configuration” symbol “A” includes a 4 per cent tolerance.

19. GRBP resumed its consideration of the ETRTO proposal to extend the scope of this UN Regulation to tyres of the speed category symbol E in order to accommodate the technical evolution of agricultural and forestry vehicles (ECE/TRANS/WP.29/GRBP/2023/9, GRBP-78-22). GRBP adopted the proposal and requested the secretariat to submit it for consideration and vote at the March 2024 sessions of WP.29 and the Administrative Committee (AC.1) as draft Supplement 21 to UN Regulation No. 106.

GRBP-78-22 | UN R106: Response to comments on document GRBP/2023/9 Information concerning discussions on the proposals to extend the scope to ‘E’ speed symbol.

GRBP/2023/9 | UN R106: Proposal for amendments Proposal to extend the scope of the speed category E to align with the technical evolution of agricultural and forestry vehicles.

20. The expert from ETRTO introduced a new design of the C3 Standard Reference Test Tyres (SRTTs) that are used as reference tyres for snow grip and wet adhesion performance (GRBP-78-28-Rev.1). The expert for Japan posed a question. The Chair invited ETRTO to submit a working document for consideration at the next session.

GRBP-78-28/Rev.1 | New design C3 standard reference test tyres

21. The expert of the Informal Working Group on Wet Grip Performance of Tyres in Worn State (IWG WGWT) presented their status report (GRBP-78-16) and draft updated Terms of Reference (GRBP-78-15). GRBP adopted the revised Terms of Reference, as laid down in annex III to the session report.

GRBP-78-15 | Worn Tyres: Proposal for revised Terms of Reference for the working group

22. The expert of IWG MU presented analyses of measurement uncertainty made by ETRTO and the experts from the project on Strengthening the Effect of quieter tyres on European Roads (STEER) (GRBP-78-06). The expert from IWG MU also gave an update on the C2 tyres noise temperature correction (GRBP-78-04). GRBP took note of these documents.

GRBP-78-04 | UN R117: C2 noise temperature correction update Proposal from the Noise Measurement Uncertainties informal group to update provisions related to temperature sensitivity.

GRBP-78-06 | UN R117: ETRTO and STEER Analysis of Measurement Uncertainty Submitted by the Chair of informal group on Measurement Uncertainties.

23. The expert from IWG MU proposed measures to reduce variability (ECE/TRANS/WP.29/GRBP/2023/19 and GRBP-78-05). GRBP adopted the proposal, as laid down in GRBP-78-05, and requested the secretariat to submit it for consideration and vote at the June 2024 sessions of WP.29 and AC.1 as draft Supplement 2 to the 04 series of amendments to UN Regulation No. 117.

GRBP-78-05 | UN R117: Proposal for Supplement 2 to the 04 series of amendments Proposal from the informal group on Measurement Uncertainties, <u>superseding</u> the proposal in document GRBP/2023/19.

GRBP/2023/19 | UN R117: Proposal for Supplement 2 to the 04 series of amendments Proposal from the Measurement Uncertainties informal group to introduce measures to reduce variability in noise measurements.

24. The expert from AAPC recalled GRBP-77-23 from the previous GRBP session and presented GRBP-78-33 with modifications to the rolling resistance values for LT-marked tyres. According to him, for reasons of safety and durability, some heavy-duty pickup trucks in a specific geographical region require LT-marked C3 tyres with performance characteristics suited to their use in rough terrains and for industrial/agricultural purposes which result in rolling resistance values higher than specified for C3 tyres in general. Therefore, he proposed to make an exception for such LT-marked C3 tyres in the rolling resistance tables.

25. The experts from France, ETRTO and OICA pointed out the need to study the proposal in more detail. Some experts feared that the requested exception for one region may have global implications. GRBP invited AAPC to liaise with the interested experts with a view to bringing more elements into consideration at the next session.

GRBP-77-23 | UN R117: Request for consideration of a special case during the 78th (August 2023) GRBP session Request to allocate time on the agenda of the 78th session for consideration of performance requirements for tyres used on heavy-duty pickup trucks designed for professional tasks on rough terrains.

GRBP-78-33 | UN R117: Proposal for amendments Proposal to amend rolling resistance provisions with regard to heavy-duty-use light trucks.

26. The expert from the Russian Federation tabled amendments that clarify certain provisions (ECE/TRANS/WP.29/GRBP/2023/20, GRBP-78-03). The experts from Germany and ETRTO posed several questions and, together with the experts from France and the Netherlands, stated that they would send written comments to the expert of the Russian Federation. GRBP agreed to keep this issue on the agenda of the next session.

GRBP-78-03 | UN R124: Proposal to amend document GRBP/2023/20

GRBP/2023/20 | UN R124: Proposal for a Supplement Proposals:<ul><li>Para. 2.2.3.: Information related to construction materials is clarified.</li><li>Para. 2.2.4.: Deleted, since its content is covered by paragraph 2.2.8. in the proposed wording.</li><li>Para. 2.2.8.: The notion of the wheel geometric shape is clarified.</li><li>Para. 2.9.: The notion of defects caused by the production process is clarified. Only in the Russian language it is clarified that the crack propagation is actually a length and a depth of the crack. The proposed text makes it possible to distinguish between a crack that occurred during testing and a scratch, which may be an acceptable manufacturing defect.</li><li>Para. 3.1.2.13.: The technical description of the wheel is supplemented with information describing the product quality control in the production process.</li><li>Para. 5.1.6. and Annex 3: The application of optional marking is aimed at providing the consumers with information on the quality control of the manufactured wheel, as well as facilitating the selection of wheels with the required characteristics by consumers in case of providing with incomplete information on suitable vehicle types in accordance with paragraph 1.2. of Annex 10.</li><li>Annex 4, para. (а): The language of the provision is clarified.</li><li>Annex 4, paras. (b) and (d): Deleted, since the existing experience of testing confirms that the mechanical properties of the raw materials are not comparable with the mechanical properties of finished products (wheels). In this regard, there is no need to test the raw materials.</li><li>Annex 4, para. <notextile>(с)</notextile>: The list of critical zones on wheels where to take the material to check its characteristics is clarified. These critical zones shall be specified by the manufacturer in the application documentation, and they can also be specified by the technical service. A description of the characteristics of the material taken from paragraph (b) is provided, since this paragraph is deleted. Only in the Russian language the terms concerning the measured values have been changed.</li><li>Annex 4, para. (e): It is specified that the analysis of metallurgical defects is carried out in the most loaded spots of the wheels. These spots shall be specified by the manufacturer in the application documentation, and they can also be specified by the technical service. The analysis shall be carried out in comparison with the permissible defects specified by the manufacturer.</li><li>Annex 6: A recommendation is added to identify cracks occurred as a result of the test by using penetrating paints.</li><li>Annexes 7 and 8: The pressure drop in the tyre as a consequence of testing the wheel assembly with the tyre may not be due to damage to the wheel, but to damage to the tyre. To eliminate uncertainty in the interpretation of the test results, it is necessary to determine the cause of the tyre pressure drop. If the pressure drop in the tyre was caused by its damage, then it is necessary to carry out the tests again, using a new tyre.</li></ul>

27. The expert from the Russian Federation proposed a correction to the Russian title of “rotating bending test” from annex 6 to UN Regulation No. 124 (ECE/TRANS/WP.29/GRBP/2023/21). The secretariat pointed out that this issue would be resolved between the secretariat and the United Nations translation services by issuing the necessary corrigenda to the existing documents and that a GRBP decision was not required. GRBP took note of this information.

GRBP/2023/21 | UN R124: Proposal for a corrigendum to the Russian language version of the text

28. The experts of the Task Force on Tyre Abrasion (TF TA) reported on their activities (GRBP-78-26) and presented two draft methods for measuring tyre abrasion: a real on-road driving method (GRBP-78-17) and an indoor drum method (GRBP-78-18). GRBP invited all experts to study both methods and provide comments to TF TA not later than 21 September 2023.

29. The experts from Finland, Norway and Sweden expressed concerns that ice tyres were not covered by the proposed test methods. The expert from TF TA replied that they either would need to be excluded from the scope or that a separate test procedure should be developed for them. The expert from ETRTO pointed out a tiny market share of ice tyres and felt that it would not be feasible to test abrasion of these tyres on icy roads.

30. The expert from OICA introduced preliminary results of their tyre abrasion study (GRBP-78-32). GRBP took note of this information and look forward to receiving the final results at the next session.

GRBP-78-17 | Tyre abrasion: Vehicle method for measurement of tyre-to-road abrasion rate in real driving environment

GRBP-78-18 | Tyre abrasion: Measurement per unit distance travelled — Method of drum

GRBP-78-26 | Task force on Tyre Abrasion status report

GRBP-78-32 | UTAC Tyre Abrasion Study for ACEA

31. The expert from the small group on retreaded tyres reported on their activities (GRBP-78-29) and briefly introduced the solution envisaged by the group:

• Adoption of a new UN Regulation for type approval of retreaded tyres with regard to their snow performance without changing the technical requirements compared to the current text of UN Regulation No. 109 (GRBP-78-31), and
• Adoption of a new 01 series of amendment to UN Regulation No. 109 without the snow performance, with the aim to clarify the administrative requirements after a certain period with adequate transitional provisions (GRBP-78-30).

32. GRBP invited all experts to study both options and to provide their feedback to the small group on retreaded tyres, with a view to preparing for the next session a working document which would contain a draft new UN Regulation and amendments to both UN Regulations Nos. 108 and 109.

GRBP-78-29 | Proposal to split retreaded tyre regulation Small group (France, Netherlands, ETRTO, BIPAVER) proposal to restructure retreaded tyre requirements and regulations.

GRBP-78-30 | UN R109: Proposal for amendments Small group proposal to split retreaded tyre requirements into a new UN Regulation.

GRBP-78-31 | Retreaded tyres: Proposal for a new UN Regulation Proposal from a small group effort for uniform provisions concerning the approval of pre-cured tread materials which are used for producing retreaded tyres or the approval of retreaded tyres produced by using mould cure process with regard to their snow performance.

33. GRBP took note of the Task Force on Vehicle Sound (TF VS) status report (GRBP-78-35).

GRBP-78-35 | Vehicle Sound task force status report to GRBP

34. GRBP recalled the discussion reflected in paragraph 6 above.

GRBP-78-08 | RE3: Proposal for a Supplement 1 to Revision 7 Proposal from the informal group on Measurement Uncertainties to introduce provisions on exterior noise measurements when performing type-approval, COP or, field testing (e.g., market surveillance).

35. No new information was provided.

36. GRBP took note of the highlights of the March and June 2023 sessions of WP.29 on GRBP and common issues (GRBP-78-27).

GRBP-78-27 | General information and GRBP highlights from the March and June 2023 WP.29 sessions

37. The Chair presented a revised list of priorities (GRBP-78-02). The experts from France and OICA commented on the list. The Chair invited other experts to send their comments to him, in order to update the document accordingly.

GRBP-78-02 | GRBP: Work priorities for 2023-2024

38. GRBP noted that the Inland Transport Committee (ITC), at its February 2023 session, had decided to develop a climate change mitigation strategy and requested its subsidiary bodies for inputs (GRPE-89-06). WP.29, at its June 2023 session, had mandated its Working Party on Pollution and Energy (GRPE) to take the lead in preparing a coordinated WP.29 response and had requested other Working Parties (GRs) to send their contributions to GRPE. In turn, GRPE had established a task force on the ITC climate change mitigation strategy (GRPE-89-39). Following a brief discussion, the Chair invited experts to think over possible GRBP contributions to the strategy and to send their ideas to GRBP not later than 8 September 2023.

GRPE-89-06 | Development of the ITC Strategy on reducing greenhouse gas emissions in inland transport

GRPE-89-39 | Proposal for GRPE contribution to ITC climate-change mitigation strategy

39. On behalf of the Special Interest Group on Automated Vehicles Regulation Screening (SIG AVRS), the expert from the Netherlands reported on their activities (GRBP-78-24). He pointed out that, as a matter of priority, SIG had decided to consider UN Regulations Nos. 28, 51 and 138 with the intention to amend them preferably with supplements. GRBP invited all experts to join the work of SIG AVRS.

GRBP-78-24 | GRBP AVRS: Progress report on screening of regulations for application to ADS vehicles

40. GRBP noted that the secretariat had received a letter from the Civil Association Anti-Noise Environmental Monitor on the possible incompatibility between the sound limits for buses of UN Regulation No. 51 and the guidelines of the World Health Organization (WHO) (GRBP-78-25). Stressing on its constant efforts to reduce the sound limits in UN Regulation No. 51, GRBP pointed out that the noise level figures in UN Regulation No. 51 and the WHO guidelines were not directly comparable for the following reasons:

1. different distances from the sound source;
2. the WHO guidelines operate with average noise levels while UN Regulation No. 51 refers to peak noise levels;
3. the tests of UN Regulations No. 51 include acceleration at wide open throttle which is uncommon in real bus traffic.

GRBP-78-25 | UN R51 and WHO maximum noise levels

41. GRBP noted that Ms. F. Silvani and Mr. M. Tyagi of OICA would no longer participate in GRBP, due to their new functions. GRBP thanked them for their valuable contributions and wished them success in the future.

42. For its seventy-ninth session, scheduled to be held in Geneva from 6 to 9 February 2024, GRBP decided to keep the same structure for the provisional agenda. GRBP noted that the deadline for the submission of official documents to the secretariat would be 14 November 2023, twelve weeks prior to the session.

43. In compliance with Rule 37 of the WP.29 Rules of Procedure (ECE/TRANS/WP.29/690/Rev.2) and Rule 42 of the ECE Rules of Procedure (E/ECE/778/Rev.5), GRBP re-elected by acclamation Mr. S. Ficheux (France) as Chair and Mr. B. Schüttler (Germany) as Vice-Chair for the year 2024.