DETERMINATION OF BACKGROUND NOISE WHEN DESIGNING SANITARY PROTECTION ZONES AND AIRPORT ZONES

Abstract

When hygienic standards for regulating noise factor in the environment are developed in accordance with the existing
regulatory-methodical base, it is necessary to take into account all possible sources of noise that are located in close proximity to an object that produces adverse effects (noise exposure). Noise produced by such sources is taken into account as background one. It is especially important to take background noise into account when designing zones with specific purpose for their use (specific zones) and in a case when noise is a priority exposure factor (in particular it is true for sanitary protection zones (SPZ) and zones near airports and airfields (airport zones or AZ) or when examining project data. The present work generalizes methodical approaches to taking background noise into account and also dwells on a procedure for combining calculated and instrumental data via energy summation. It contains results obtained via testing this combined methodical approach on a large industrial enterprise located in a large industrial city. As per acoustic calculation results noise levels varied from 29.7 dBA to 44.4 dBA within boundaries of an established sanitary protection zone. Instrumental measurements performed in a zone influenced by the examined enterprise at two control points located in the closest residential area showed noise levels varying from 40-43 dBA (at night) to 48-50 dBA (during a day). Having compared calculated and field data, we obtained discrepancies for the control points that varied from 1.0 dBA to 27.0 dBA and it allowed obtaining summated (aggregated) noise level varying from 40.4 to 51.0 dBA accordingly at the control points within the SPZ. Our experience and methodical approaches to calculating and assessing background noise exposure will allow meeting legal requirements on taking side sources of noise exposure into account as background noise within specific zones and passing sanitary-epidemiologic examinations with satisfactory results.