Methodology for Uncertainty Estimation of Long-Term Environmental Noise Measurements

The ISO 1996 series harmonize the methods for the description, measurement and assessment of environmental noise from all source types. In addition, the standards contain the guidelines for estimating the uncertainty of environmental noise measurements that consider the impact of different sources of uncertainty. The standards do not describe in detail the procedure for estimating the measurement uncertainty, but they can be used as a foundation for developing a detailed procedure based on the conducted acoustic measurements and collected data important for sound propagation. The aim of this paper is to provide a detailed step-by-step procedure for estimating the uncertainty of long-term environmental noise measurements conducted during long-term time intervals consisting of several reference time intervals. The input data are a large number of independent measurements of equivalent continuous sound pressure levels at the assessment point under well-defined sound emission and meteorological conditions. The measurement results are stratified into different windows, i.e., a combination of sound emission and meteorological conditions. The output data is the uncertainty of long-term environmental noise measurements estimated using the measured data obtained by the continuous environmental noise monitoring, taking into account possible sources of measurement uncertainty.