Proposal to update the reference to the latest version of ISO 10844 and to introduce transitional provisions for the shift of the test track requirements from ISO 10844: 1994 to ISO 10844: 2014.

Based on the outcomes of a European Commission study, proposal to clarify the text and align its provisions with other vehicle sound regulations, especially UN R41, including to replace references to “two wheeled moped” with the term “L1 category vehicles” (and consequently to replace references to “moped” with “vehicle”) and to replace the term “noise” with “sound” (except for references to background noise) throughout the regulation. It proposes improved terminology and definitions, including new ones, improved sound emission testing conditions and procedures. It also introduces sound emission measurement through new testing of in use vehicles in motion.

Proposal to clarify that conditioning of a silencing system is necessary only in cases where exhaust gases come into contact with silencer fibrous materials.

Proposal to exclude pure electric vehicles, including vehicles with auxiliary electric propulsion, from the scope of the regulation, to include sound-level measurement conditions for powered cycles equipped with compressed air engine and to introduce sound-level limits for powered cycles.

Proposal to align the 02 series of amendments to UN Regulation No. 63 with standard 10844:2014 of the International Organization of Standardization (ISO).

Proposal to allow the use of state-of-the-art test tracks per the latest standard ISO 10844:2021.