Proposal from the informal working group on the International Whole Vehicle Type Approval (IWVTA) system.

These general guidelines, based on ECE/TRANS/WP.29/1044/Rev.2, as amended by WP.29-182-11, provide guidance to subsidiary bodies of the World Forum for Harmonization of Vehicle Regulations on procedures for making and amending UN Regulations and drafting their scope, administrative provisions, alternative requirements and cross-references. The guidelines emphasize mutual recognition of UN type approvals and clarify that UN Regulations are optional for Contracting Parties. They address procedures for new UN Regulations, series of amendments, supplements, and corrigenda, with transitional provisions specifying dates when Contracting Parties must accept or may refuse approvals. Special procedures apply to UN Regulation No. 0 on International Whole Vehicle Type Approval, amended no more than once per year with Date (b) by default set at 1 September of the year following adoption.

Proposal for amendments that allows for tyre marking methods other than moulding.

Proposal to clarify UN R41 and introduce provisions to improve testing to be more representative of real-world operation by expanding the scope of test and to align the Regulation with ISO 10844:2014, replacing provisions from ISO 10844:1998 (and proposing a clearer image for Figure 1).

Proposal to align the 04 series of amendments with ISO 10844:2014, replacing provisions from ISO 10844:1998 (and proposing a clearer image for Figure 1).

Proposal to

1. Change the definition of the tyre size designation by including prefixes and suffixes as well as the code for the tyre structure
2. Clarify the use of sizes listed in Annex 5
3. Move the definition of “reinforced” into a paragraph that is not subordinated to the definition of “Structure of a tyre”
4. Correct references and typographical errors
5. Rearrange paragraphs and amendments in order to increase readability
6. Delete an unnecessary cross-reference to UN Regulation No. 54
7. Change the definition of “bias-belted”
8. Amend the definition of “snow tyres” by replacing “ordinary (road-type) tyres” (which is not defined) by “normal tyre”, removing the note that snow tyres generally have more widely spaced ribs or blocks
9. Include a general provision addressing the gap between the effective date of entry into force and the date of notification of the adoption of the Supplement to the Contracting Parties
10. Keep the restriction of measurement of overall diameter after load/speed test only to diagonal tyres (For radial the variation of outer diameter of the tyre, measured six hours after the load/speed performance test as specified in paragraph 2 of Annex 7, is far below ±3.5 per cent from the outer diameter as measured before the test.)
11. Remove use of the word “moulding”
12. Resolve conflicting provisions in Annex 2 concerning the minimum size of the approval mark
13. Clarify that mounting motorcycle tyres on motorcycle rims is the standard configuration and that “M/C” marking is optional for the sizes listed in Annex 5.

Proposal for alternative language regarding markings to avoid use of the term “moulded” which could be interpreted as a technical design restriction and to add a reference to “log-skidder” tyres.

1. Improve the reproducibility of the test method (in alignment with ISO 23671)
2. Include maximum load and pressure information per ASTM F2493-19
3. Update the test report templates accordingly
4. Remove the limitation for “moulded” markings
5. Transition from SRTT14 to SRTT16
6. Align track friction requirements for track characterization per the transition
7. Clarify vehicle selection provisions
8. Introduce transitional provisions

Proposal to align the acceptance criterion listed in the table in Annex 8, paragraph 3, with the negative rating criterion listed in paragraph 5 (c): total loss of inflation pressure within one minute. This change clarifies that only a complete decrease in the pressure in the tyre due to its depressurization is a negative evaluation criterion when conducting an impact test.

Proposal to align with the provisions of European Union Regulation 2019/2144 and to introduce the TPMS requirements for all vehicle categories.