Proposal from GRBP to align the definitions of “diagonal” or “bias-ply” and “bias belted” tyre structures to the definitions given in UN R30 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.
19. GRBP considered a proposal that had been prepared by the expert from ETRTO with the aim to align the definitions of “diagonal”, “bias-ply” and “bias belted” tyre structures with the definitions in UN Regulations Nos. 30 and 75 (ECE/TRANS/WP.29/GRBP/2022/7). GRBP adopted the proposal and requested the secretariat to submit it for consideration and vote at the June 2022 sessions of WP.29 and AC.1 as draft Supplement 20 to UN Regulation No. 106.