Proposal to:

1. Update reference to ISO 4000-1:2024 (published in March 2024)
2. 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”)
3. Clarify the nominal rim diameter.
4. Amend the definition of principal grooves by eliminating the circular reference between this definition and the position of tread wear indicators.
5. Introduce definition of tread depth (used in the requirements for special use and professional off-road tyres)
6. Clarify the calculation of tyre section width
7. Claify the D_max requirement for snow tyres.

Proposal to

1. 1. Add a generic reference to the Consolidated Resolution on the Construction of Vehicles (R.E.3) in footnote 1
2. Make editorial corrections to the type of tyre and additional service description definitions
3. Clarify the definition of nominal rim diameter (in line with the proposal for amending UN R30)
4. Amend the definition of principal grooves (in line with the proposal for amending UN R30
5. Introduce a definition for tread depth (used in the requirements for special use and professional off-road tyres)
6. Introduce definition for free rolling tyre and front axle, and related revision of markings (ref. GRBP-80-03 and GRBP-80-26)
7. Clarify the D_max requirement for snow tyres
8. Simplify rhz wording of the requirements for professional off-road tyres
9. Add an indication for whether a special use tyre is a professional off-road tyre to the communication form (in line with UN R30).

Proposal to

1. Add a generic reference to the Consolidated Resolution on the Construction of Vehicles (R.E.3) in footnote 5.
2. align the categories of use to “normal tyre”, “snow tyre” and “specialuse tyre” in line with UN R30 and 54, to introduce a definition of “normal
   tyre” and consequently make use of the terms “snow tyre” and “special-use tyre” that are already defined
3. reformat Annex 5, Table 7 to present the tyre-size designations in a consistent way and to provide explicitly that tyre-size designations from this table may also be used for tyres in bias-beltedvstructure
4. Include the suffix “M/C” that is defined as mandatory for motor-cycle tyres with rim diameter code 13 and above in the figure illustrating the sidewall markings in Annex 3 and to present the markings in a clearer way
5. Add provisions for the dimensional requirements of moped tyres
6. Add a factor for the centrifugal radius of snow tyres and special-use tyres with a speed category above 210 km/h
7. Give the footnotes in the main body of the regulation an unequivocal number to avoid confusion when referencing to a particular footnote
8. Include several editorial corrections to increase the consistency of the text (e.g. consistent use of the terms defined in section 2, such as “tyre-size designation”, “load-capacity index”, “speed-category symbol”).

Proposal to

1. Update standard reference to ASTM F2493-24 and ISO 4000-1:2024
2. Align the definitions of tread groove and principal grooves with proposals for UN R30 and R54
3. Simplify the wording of the requirements for professional off-road tyres
4. Correct the transitional provision in paragraph 12.23. to specify approvals “first issued after 31 August 2028”.

Proposal to

1. Clarfy the scope to reflect that adhesion performance on wet surfaces (wet adhesion) is required not only for C1 tyres, but also C2 and C3 tyres
2. Update standard reference to ASTM F2493-244, F3611-24, F3676-24, F3675-24 and ISO 4000-1:2024
3. Align the definitions of tread groove and principal grooves with proposals for UN R30 and R54
4. Simplify the wording of the requirements for professional off-road tyres
5. Correct the transitional provision in paragraph 12.23. to specify approvals “first issued after 31 August 2028”.

Proposal to:

1. Correct the description of a tyre to exclude aspects outside the scope of UN R108
2. Align the snow tyre definition to UN R109 and 172
3. Clarify the definition of nominal rim diameter
4. Clarify the definition of principal grooves by eliminating the circular reference between this definition and the position of tread wear indicators
5. Introduce a definition for tread depth (used in the requirements for special use and professional off-road tyres)
6. Amend para. 4.1.5.3.2. to remove the retreaded reference to traction tyre classification because it is not applicable to tyre of class C1
7. Clarify the calculation of the tyre section width
8. Replace “XXX” with the UN Regulation No. 172 in the references to the approval of retreaded tyres with regard to their snow performance and/or classification as traction tyre.

Proposal to:

1. Correct the description of a tyre to exclude aspects outside the scope of UN R109
2. Clarify the definition of nominal rim diameter
3. Clarify the definition of principal grooves in line with the proposal for UN R54
4. Amend para. 6.4.4.2. to clarify that the UN R117 certificate may be used for obtaining the type approval under UN R172 of retreaded tyres classified as traction tyre
5. Simplify the wording of the requirements for professional off-road tyres
6. Replace “XXX” with the UN Regulation No. 172 in the references to the approval of retreaded tyres with regard to their snow performance and/or classification as traction tyre.

Proposal to:

1. Add a generic reference to the Consolidated Resolution on the Construction of Vehicles (R.E.3) in footnote 1
2. Align title of para. 5 with its contents (paras. 5.1. and 5.2.)
Align the title of para. 6 with corresponding paras. in UN R30, 54, 75, 106 and 117</li<
3. Clarify that all temporary use spare units can by composed by using tyres of any category of use
4. Align the snow tyre definition with UN R30, 54 and 117
5. Clarify that tyres for use in severe snow conditions are also applicable to the category of use ‘special use tyres’
6. Clarify which service conditions can apply the coefficient given in paragraphs 5.2.4.3.1. and 5.2.4.3.2.
7. Add Class C3 tyres to the speed category symbol and load capacity index definitions
8. Introduce definitions of free rolling tyre and front axle and revise markings accordingly (ref. documents GRBP-80-03 and GRBP-80-26)
9. Clarify reporting the name of the symbols used for tyre for use in severe snow conditions in line with UN R117 and 164.

Proposal to:

1. Add new reference tyres C3 SRTTs 19.5 and 22.5 siped and related transitional provisions
2. Simplify the wording of the requirements for
   professional off-road tyres
3. Make editorial corrections where needed throughout the text.