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A group within the International Organization for Standardization has worked out a standard for a road surface intended to be used during vehicle noise measurements according to the ISO 362 and 7188 procedures. The surface should be equally suited for use in similar measuring procedures where full-throttle operation of vehicles is needed and where the influence of the surface on noise emission and propagation must be kept at a minimum. Several test tracks have been laid according to the proposed specifications. A Round Robin Test has been conducted in which five cars and one truck were run on a number of test tracks in Europe and Japan. The results show that the surface meets the basic requirements of giving low tire/road noise while still having negligible sound absorption characteristics. Also, the site-to-site variability is low. In this paper, the convener of the working group presents the work and a preliminary proposal.

This paper summarizes a presentation that attempts to describe what has recently been done and is planned to be done to relieve the problem of traffic noise, with focus on tire/road noise emission. The paper shows that there is at the moment in Europe, Japan and in countries accepting ECE Regulations a quite intensive development aiming at reduction of road traffic noise, but with initial high ambition often ruined when it comes to the political process. The author thinks that it is likely that many Asian countries under fast development will adopt similar policies as Europe and Japan, although actual implementation may be slower than formal policies would suggest. This positive development applies to exterior noise from light vehicle power units, from car tires and from pavement properties. The exception is trucks and buses and their tires, which are left without significant improvement in the foreseeable future and thus may have an effect on the future perception of truck traffic.