Verification of Railways Noise Mapping Using CNOSSOS-EU: Case Study on Freight Trains

Freight trains are a relevant source of environmental noise and require an acoustical assessment to quantify the exposure of the population using noise mapping. Once the results of the noise calculations have been developed, it might be necessary to adopt mitigation strategies that can be validated using these noise models. It is becoming increasingly common to undertake some form of validation exercise to cross-reference the calculated levels with measurements to reduce the uncertainty in the action planning. Based upon the results of the monitoring, the measured data may then be stratified regarding the source data and meteorological data and introduced into the calculation model, to enable the model to replicate the situation during the measurement windows (meta-models). The results from the calculations of each of these meta-models may then be compared with the noise measurement results as the basis for the validation study. This paper presents an overview of a verification project undertaken in South America where such a process was followed using the CNOSSOS-EU as the basis of comparison.