5. The experts from the Informal Working Groups on Measurement Uncertainties (IWG MU) and on Additional Sound Emission Provisions (IWG ASEP), as well as from ISO, presented editorial corrections and clarifications to the 03 series of amendments to UN Regulation No. 51 (ECE/TRANS/WP.29/GRBP/2023/12, GRBP-77-05 and GRBP-77-26). GRBP supported these amendments and noted that they were already included in ECE/TRANS/WP.29/2023/2 that would be considered by WP.29 at its forthcoming session in March 2023.

6. The expert from ISO proposed to bring the latest ISO 10844:2021 standard test surface into UN Regulation No. 51 (ECE/TRANS/WP.29/GRBP/2022/13). GRBP adopted this proposal and requested the secretariat to submit it for consideration and vote at the March 2023 sessions of WP.29 and AC.1 as part of draft Supplement 8 to the 03 series of amendments to UN Regulation No. 51.

14. The expert from ISO reported on technical measurement development for standard ISO 16254 (GRBP-75-03). He also presented an updated standard ISO 10844:2021 (GRBP-75-02-Rev.1/Add.1) and proposed to include it into UN Regulations Nos. 51, 117 and 138 (GRBP-75-02-Rev.1). GRBP invited the expert from ISO to submit an official document to the next session.