Traffic noise modelling and measurement: Inter-laboratory comparison

Abstract

Traffic noise emission and its propagation can be effectively measured and modelled. Results of traffic noise modelling are very close to the results of measurement, typically within ±3dB range in case of noise propagation around elementary situations. In a real complex environment, the deviation of results is larger. The procedure of gathering the information about the traffic attributes and the elements composing the propagation path is essential for traffic noise modelling, however it differs from laboratory to laboratory. The deviation of input data and consequently the deviation of modelling results occur, if different sources of information are used. Fourteen inspection bodies participated in the inter-laboratory comparison, which was organized in order to compare procedures of different laboratories with a purpose to identify key parameters influencing the deviation of noise modelling results. Presented inter-laboratory comparison (ILC) of traffic noise modelling is particularly reliable because it includes both, the comparison of modelling results and the comparison of measurement results. Assessment of noise level relative to the absolute reference value was not the primarily objective of the ILC, the main goal was the analysis of the risk of systematic errors. Conclusions of the study indicate that traffic noise models and noise propagation models can be regarded as an extrapolation of measurement results from one location to a wider surrounding area.