Proposal to clarify the text and align the provisions of UN R9 with other vehicle sound regulations, especially UN R41, pursuant to research conducted by the European Commission.

Proposal to align ASEP for high powered L4 and L5 vehicles, used for passenger transport, is proposed in line with UN Regulation No 41.04 due to comparable sound emissions levels of L4 and L5 vehicles with the ones of L3 vehicles and the possibility of applying similar measurement methods for sound emissions for those vehicle categories. This is also supported by the Commission study on enhanced sound requirements for mopeds, quads and replacement silencers of L-category vehicles which resulted in amendments to UN Regulation Nos 9, 63 and 92 (ref. document WP.29/2017/2).

Proposal to introduce ASEP requirements for L₄ and L₅ category vehicles with PMR > 50 W/kg. The proposal aligns ASEP for high powered L₄ and L₅ vehicles, used for passenger transport, with UN Regulation No 41.04 due to comparable sound emissions levels of L₄ and L₅ vehicles with the ones of L₃ vehicles and the possibility of applying similar measurement methods for sound emissions for those vehicle categories. This proposal is supported by the Commission study on enhanced sound requirements for mopeds, quads and replacement silencers of L-category vehicles which resulted in amendments to UN Regulation Nos 9, 63 and 92 (ref. document WP.29/2017/2).

Proposal to correct an inconsistency in document GRB-68-22 (adopted along with GRB/2018/7 and submitted for consideration at the March 2019 WP.29 session as WP.29/2019/6) regarding the ASEP exemption conditions for vehicles with variable gear ratios or automatic transmission with non-lockable gear ratios.