Monitoring of noise reduction from traffic speed control

Abstract

In November 2005, at the Hague, Amsterdam, Rotterdam and Utrecht, a 80 km/u speed limit was introduced on sections of motorways in the Netherlands. The aim was to evaluate the effects on noise, air quality and the circulation of the traffic. RIVM investigated the effects of noise emission by direct measurement at the sections with speed limit. This paper gives the results from continuous monitoring of noise levels that was started at July 2005 and continued up to November 2006. In the presentation the average measured effects on the equivalent noise emissions at the different sites will be given. Also the effects of traffic speed reduction on dwellings in the neighborhood of the motorways were evaluated using noise maps. Furthermore, apart from the average equivalent noise levels, the statistical noise indicators L5, L10, L70, and L95 were continuously monitored. It was found that speed reduction induces more reduction on maximum noise levels than on the average (equivalent) noise levels, probably due to a more steady and even distribution of traffic speeds.