Adopted by the Forum and integrated into the regulation via Revision 1.

Table prepared by OICA highlighting various elements in the consideration of noise in UN Regulation Nos. 9, 28, 41, 51, 59, 63, 92, and 117.

Table showing the status of the revisions to selected UN Regulations, including the new UN R127 (LED lighting) and R128 (Pedestrian safety). Revisions consolidate and update regulations as a single text.

Notice of the European Union’s intention to accede to UN Regulation No. 41 and the possible accession to Regulations 9, 63, and 92. The EC requests GRB input before deciding whether to pursue a separate legislative process to establish new provisions for these related noise rules.

Proposal to specify that conditioning of exhaust or silencing systems is required only in cases where the fibrous materials are in contact with exhaust gases because there is no possibility for the dispersion of fibrous materials under any other condition.

Table of potential areas for future GRB work prepared during an informal meeting held in Paris during 2-3 July 2015.

Overview of discussions for the future development of vehicle noise regulations prepared by the GRB secretariat.

UN R51 specifies that conditioning of a silencing system is necessary only in cases where exhaust gases come into contact with silencer fibrous materials. This proposal would apply the same concept in L category noise regulations.

Explanation of recommendations developed for the European Commission by LAT, TNO, Heinz Steven, and TÜV Nord for the improvement of the regulations with regard to additional sound emission provisions.

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

Proposal to update the provisions of Regulation No. 92 to a level at least equivalent to the corresponding provisions in the European Union legislation. The document proposes improved terminology and definitions, including new ones, improved sound emission testing conditions and procedures. It also introduces anti-tampering provisions and an “Additional sound emission provisions” (ASEP) statement by the manufacturer.

Presentation concerning the proposals to clarify and update the texts and to align their provisions and terms.

Proposal to update the provisions of Regulation No. 92 to a level at least equivalent to the corresponding provisions in the European Union legislation. The document proposes improved terminology and definitions, including new ones, improved sound emission testing conditions and procedures. It also introduces anti-tampering provisions and an “Additional sound emission provisions” (ASEP) statement by the manufacturer.

Discussion of motorcycle and related vehicle noise issues, especially related to aftermarket modification (non-original replacement exhaust silencer systems (NORESS)).

Presentation on the status of the European Commission-sponsored study to investigate the potential of and develop a proposal for new sound limits of L-category vehicles under Euro 5.

German authorities have carried out a study to assess the possibility for measuring UN R41.04-approved L category vehicles using typical “roadside check” equipment. The study found that such equipment provides a “lite” version of the UN 41.04 procedures that is useful in evaluating real-world performance. Germany intends to pursue a national “pass-by lite” test directive for UN R41-approved motorbikes and for non-original replacement exhaust silencer systems (NORESS) roadside and periodic technical inspections.

Proposal to introduce provisions for non-original replacement silencing systems (NORESS, independent aftermarket muffler systems) with multiple, manually or electronically adjustable, rider-selectable operating modes or variable geometries (NORESS with “flexibilities”). These "flexibilities enable the replacement systems to meet the requirements of Annex 3 (i.e., during testing) while producing much higher noise (sound pressure) outside the Annex 3 conditions. This amendment would require such NORESS to meet the ASEP requirements of UN R9 and UN R41. The amendment further introduces language taken from UN R51. In effect, NORESS with flexibilities performance under normal driving conditions would not be permitted to deviate from its performance under testing.

Presentation in support of Germany’s proposal for amendments to UN R92 on non-original replacement exhaust silencing systems.

Proposal to introduce requirements for non-original replacement exhaust silencing systems with multiple, manually or electronically adjustable, rider-selectable operating modes or variable geometries (NORESS with “flexibilities”). This is a consolidated version of the amended regulation with the changes marked in bold and strikethrough text.

Proposal to introduce requirements for non-original replacement exhaust silencing systems with multiple, manually or electronically adjustable, rider-selectable operating modes or variable geometries (NORESS with “flexibilities”). This is a consolidated version of the amended regulation. For more information on the changes, see document GRB/2018/6 where the changes are marked in bold and strikethrough text.

Proposal to align UN R92 with the latest amendments to UN R41 and to reduce the number of exhaust system types (allowing for slight differences in drawings) to be approved by NORESS manufacturers.

Presentation on proposed amendments to align with the latest amendments made on UN Reg 41 and to reduce the number and amount of different exhaust types to be approved by NORESS manufacturers

Proposal to provide industry guidelines on anti-tampering provisions for Non-Original Replacement Exhaust Silencing Systems (NORESS) in UN Regulation No. 92.

Proposal for a reference document concerning a general approach for how to handle measurement uncertainties under UN Regulations within the purview of GRBP.

Proposal to clarify the requirements for non-original replacement exhaust silencing systems (NORESS).

Proposal to amend document GRBP/2024/21

Proposal to strengthen anti-tampering provisions.