Sound Insulation Indices: A Proposal for Revision of ISO 717

摘要

The report offers a survey on the sound insulation indices that are most widely used in building acoustics. Analyzed are also the procedures of obtaining the indices, especially the ISO 717 reference curve system in comparison with the direct calculation of the sound reduction by the dB(A)-method. On the basis of references, the two methods are seen to be equivalent which means that a reference curve procedure is an algorithm for the respective dB(A)-method yielding an approximation for the acoustical reduction or giving the rating. Proposals for formulating the airborne and impact sound insulation indices are given. The ISO 717 system is suggested to be improved by including a traffic noise index lacking from it before. The reference curve principle will be retained and is meant to be used especially in building codes. (Copyright (c) Valtion teknillinen tutkimuskeskus (VTT) 1989.)