Based on WP.29/2025/68 as adopted during the 196th WP.29 session (23-27
Jun 2025).
WP.29/2025/68
Proposal to:
- Update reference to ISO 4000-1:2024 (published in March 2024)
- Clarify the structure indication within the tyre size designation for run flat or self-supporting tyres suitable for speeds in excess of 240 km/h (inscription “ZRF”)
- Clarify the nominal rim diameter.
- Amend the definition of principal grooves by eliminating the circular reference between this definition and the position of tread wear indicators.
- Introduce definition of tread depth (used in the requirements for special use and professional off-road tyres)
- Clarify the calculation of tyre section width
- Claify the Dmax requirement for snow tyres.
Entry into force as of 11 Jan 2026