Report of the 22nd session of TF-VS held on 1 September 2026. The session focused on cross-matrix activity for road traffic noise, with presentations on Swiss sound emission models sonROAD18 and NExUS developed by the Federal Office for the Environment. sonROAD18 is a general road traffic noise prediction model based on CNOSSOS-EU framework used for sound mapping in Switzerland since 2023. NExUS is a research model for comparing noise emissions of electric vehicles and internal combustion engine vehicles based on pass-by measurements. France, Sweden, Japan, Germany and The Netherlands proposed to present their own approaches at future sessions.
Agenda for the 23rd session of the Task Force on Vehicles Sound on 20 October 2026. The session will cover adoption of the agenda and report of the 22nd session, exchange of information on national and international requirements including presentations on quiet communities and noise sensitivity analysis, cross-matrix comparison of sound traffic modelling approaches with presentations on noise modelling and CNOSSOS-FR parameters, any other business, and arrangement of the next meeting in February 2027.
Editorial corrections to the Appendix and reference to Annex 4.
Meeting minutes documenting PMP discussions on amendments to Brakes GTR 24 and UN R179, including TF3a layout and testing topics, TF3b vehicles limited speed work, TF3c brake replacement parts with a new UNR to be introduced, and TF4 electromechanical brakes with no further progress. GTR and UNR informal documents on HD brakes were presented with trailers removed from scope, open points on PM Emission Factor units, caliper position, test input parameters, and cooling air flow value addressed, and a 3-month delay in round robin testing reported.