Proposal to amend the definition of “radial tyre” in UN Regulations No. 54, 75, 106, 108 and 109 based on the proposal for UN Regulation No. 30 in document GRBP/2021/9.

Proposal to align the definitions of “diagonal” or “bias-ply” and “bias belted” tyre structures to the definitions given in UNvR30 and R75, to improve the text with regard to description of the composition of the size designation for metric tyres, and to resolve an apparent contradiction regarding the prefixes IF and VF.