Predictability of field airborne noise isolation from laboratory testing.

Abstract

The relationship between laboratory and field noise isolation tests of nominally identical assemblies is a longstanding question in acoustics [LoVerde and Dong, J. Acoust. Soc Am. 122, 2955 (2007)]. Many building codes allow field airborne noise isolation ratings (ASTC, NIC, or NNIC) to be five points lower than the corresponding laboratory rating (STC), but the origin of this relationship is not documented thoroughly in the literature. Different wood framed floor/ceiling systems were tested multiple times in the laboratory to determine performance prior to implementation in the field. Field testing was performed in a variety of completed buildings to determine the actual acoustical performance of the assemblies that were installed. The results of this testing for airborne sound isolation is presented. The authors will present analysis of the predictability of field test results based on laboratory test and the apparent translation from laboratory to field testing.