Consolidated version of UN R54 incorporating the proposed amendments in document GRRF/2018/5.

Proposal to introduce formulae for tyre sizes in Annex 5, Table B, add sizes in Annex 5, Part II, Tables C and E for old sizes that do not follow the guidelines/formulae applicable for high flotation tyres, clarify tyre width tolerances, correct paragraph numbering and references, align the text editorially with UN R30 and to make other editorial improvements,

Proposal to correct the paragraph numbering of the original proposal for amendments to Regulation No. 54 contained in document GRRF/2017/18. The introduction of new paragraphs by Supplement 21 and the separation of paragraph 3.1. into subparagraphs 3.1.1. and 3.1.2. result in the proposed paragraph 3.1.12. being renumbered as 3.1.13.

Proposal of additional footnotes to clarify terminology differences between the US and Europe to aid in the application of the regulation.

Proposal to

1. correct the references to paragraph 3.17 in paragraph 3.1.12. to refer to 3.20
2. update a cross-reference in paragraph 3.4 to read “3.1.2.” pursuant to the earlier division of paragraph 3.1 into paragraphs 3.1.1. and 3.1.2. (consistent with UN R30)
3. delete the superfluous reference to paragraph 2.19 in paragraph. 4.1.1. (consistent with UN R30)
4. delete the word “existing” from paras. 6.1.1.2. and 6.1.2.2. (consistent with all the other tyre UN Regulations)
5. amend paragraph 6.1.4.2. to take into account the requirements for size designations in Annex 5
6. add a footnote to Annex 5, Part II, Table B to introduce the appropriate formulae in the Regulation (instead of Annex 5)
7. add a size in Annex 5, Part II, Table C for an old size that does not follow the guidelines/formulae applicable for high flotation tyres.

Proposal to

• Clarify the minimum heights for markings of tyres with nominal rim diameter codes ≥ 20 and nominal section width ≤ 235
• Clarify the minimum heights for markings of tyres with nominal rim diameter codes < 20 and nominal section width > 235
• Correct the use of uppercase letters to denote dimensions where lowercase letters had been inserted
• Correct the paragraph numbering pursuant to the adoption of Supplement 21
• Delete a redundant note at the end of paragraph 6.1.5.3.3., and
• Add specifications for tyre sizes 33×11.50R20LT, 35×11.50R17LT, 37×13.50R26LT, 36×15.50R20LT and 40×15.50R26LT.

Germany reviews problems with applying UN specifications for the marking of winter tyres, covering disparities in definitions and performance requirements across the tyre regulations (UN R30, R54, R75, R106, R108, R109 and R117). Therefore, Germany proposes that GRRF work to resolve these disparities and offers two possible solutions: 1) Introduce the definition of "Snow tyre for use in severe snow conditions” and the related performance and marking requirements established under UN R109 and R117 into UN R30, R54, R75, R108, and (possibly) R106; 2) Amending UN R117 to extend the scope of its snow performance criteria to additional tyre classes and categories, such as special tyres (POR, MPT), all terrain (AT) tyres, and retreaded tyres for passenger cars.