Determination of residual sound in quiet areas or for describing soundscapes by percentile-based method

Montano W.A.; Gonzalez A.E.; Gushiken E.I. · Proceedings of Meetings on Acoustics (2025) · DOI: 10.1121/2.0002217

Resumen

For describing or measuring residual sound levels in quiet areas, an ANSI/ASA standard recommends procedures adapted to get a single unit in dBA but not intended to characterize the sound in specific quiet spots or natural places. Wind turbines, pumping and compression stations for natural gas facilities, and other industrial facilities with high levels of low-frequency noise are usually installed near wilderness areas, so it is important to have a description of the entire soundscape in terms of sound spectrum rather than just a single LA90. It is important to know the spectrum in one-third octave band of the residual sound in a location prior to the installation of those facilities, or to identify a soundscape. An empirical method was developed using measurements recorded in samples (1 s or less), to estimate the residual sound level. By means of the percentile-based method, an algorithm removes those samples above a threshold value, and keeps those below, in order to generate a new file with the lowest sound levels contained in the original one, in that way not only the LAeq value is attained but also other descriptors, and its corresponding spectrum was constructed using the LZeq for each one-third octave band.