Noise levels in the vicinity of traffic roundabouts

Abstract An experimental procedure for analyzing roundabout noise is described. Measurement of the noise from accelerating and decelerating traffic streams on the approach roads to roundabouts at a total of 70 positions at three sites are reported together with a simulation study of noise from central island traffic. The results show that, in general, noise from the accelerating traffic streams is within ±1 dB(A) of the free flow level on the same road and that the noise from the decelerating stream is equal to or less than the free flow level. The propagation of noise from the central island is expressed in the form of a nomogram. Good agreement between predicted and measured levels was found.