Application of the new reference spectrums for transportation noise sources in sound insulation rating

Abstract

ISO 717-1 and the draft standard ISO/TC 16717-1 both recommend a reference spectrum for traffic noise without considering different transportation noises while rating sound insulation of external building elements. The field study which is summarized in this paper, provided a database about acoustic characteristics of various sources (traffic, railway, aircraft and seaway traffic) and then the proposed normalized A - weighted reference spectrums at 50-5000 Hz were introduced to ISO/TC 16717-1 formulation to obtain source-specific sound insulation descriptors (R<inf>wt</inf>, R<inf>wa</inf>, Rwr, R<inf>ws</inf>). During the study, a survey for building types, materials and constructions were conducted and the insulation Performances of the external building elements were computed in terms of the new and existing descriptors. The comparisons indicated that the reference spectrum recommended in ISO standards for traffic noise, could not represent the other types of transportation noises because of the discrepancies and thus the source-specific descriptors were essential to ensure the reliability of insulation rating. A categorization system for insulation was also proposed for the external building elements to be used at national level. © 2014 Elsevier B.V., All rights reserved.