The Working Party on Noise (GRB) prepares regulatory proposals for consideration by the World Forum/WP.29 relating to noise emissions and sound-based alerting systems. The GRB not only considers noise limits on motor vehicles, but also minimum sound requirements as vehicles have become quieter, posing concerns for vulnerable road users such as pedestrians and cyclists.

The GRB typically gathers more than 70 specialists in sound-related areas from government agencies and non-governmental organizations around the world. The GRB facilitates international cooperation in research and analysis and supervises informal expert working groups that develop technical requirements on vehicle noise.

GRB usually convenes during February and September of each year.