<p>In acoustics, in the areas of airborne sound measurement and prediction, the matter of uncertainty continues to be given short shrift in published reports and papers. Acoustical and noise control engineering practitioners of all types regularly test and report on sound emissions and imissions with little or no regard to the uncertainties involved, or even how any such identified uncertainties are to be treated or combined collectively or even quantified. In this presentation the major elements of acoustical uncertainty are discussed and are intended to be a sobering reminder to all acoustical practitioners of our inability to precisely define source sound power, or to accurately model either single or complex acoustical sources, or to precisely model or measure the far field propagation of sound emissions.&nbsp; Herein will be reviewed: a) why absolutely every acoustical measurement anywhere under any circumstances will have a precision no better than 1 dB, b) the inevitable upward creep in sound level resulting from multiple source uncertainties, c) the commensurate upward creep in uncertainty resulting from the progressive spreading with increasing distance of any far field histogram Leq – L50 due to atmospheric effects, d) the often overwhelming uncertainties due to the influences of atmospherics, ground effects and vegetation inhomogeneities, e) the often careless omission of the ‘Confidence Interval’ employed whenever uncertainty is addressed at all, and finally f) the proper method, via example, for combining the several elements of uncertainty.</p>

Uncertainty in Acoustical Measurements: An Unsettling Perspective

Paper Proceedings: https://asmedigitalcollection.asme.org/VVS/VVS2021/volume/84782

ASME 2021 Verification and Validation (VVS2021)

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