Measurements Of The Sound Transmission Loss Of Windows

Introduction The sound transmission characteristics of windows are of interest not only for specialized applications such as the control rooms of recording studios but also for the exterior shell of buildings where the intrusion of outdoor noise into homes and offices is of concern. Although transmission loss data for many types of windows are available, the results of different studies are not in close agreement. Figure 1, which is based on data taken from a recent review paper. illustrates the typical variation in published results. Although the windows involved had essentially equivalent glazing and interpane separation, the results obtained in the three sets of measurements differ appreciably. There are several reasons for discrepancies: 1. At low frequencies sound transmission is considerably affected by panel resonances whose frequencies depend on the dimensions of the panes of glass. 2. The damping and edge constraint provided by putty or other material used to seal glass in

Isolation aux sons a\ue9riens dans les immeubles d\u2019habitation

Cet article explique comment une attention accrue \ue0 la performance des syst\ue8mes permet d'am\ue9liorer l'isolation acoustique des immeubles d'habitation, et ce, de fa\ue7on \ue9conomique. On y passe en revue les notions et la terminologie associ\ue9es \ue0 l'isolation acoustique dans un syst\ue8me de b\ue2timent complet et on y pr\ue9sente des r\ue9sultats de recherche qui illustrent l'importance de certains d\ue9tails typiques des constructions \ue0 ossature en bois sur l'isolation acoustique.This Update explains how an emphasis on system performance can achieve good sound insulation in multi-family buildings in a cost-effective manner. It reviews the concepts and terminology used to describe sound insulation for the complete building system, and presents research results that illustrate how typical wood-frame construction details can determine the sound insulation actually achieved.Also available in English: Airborne Sound Insulation in Multi-Family BuildingsPeer reviewed: NoNRC publication: Ye

Optimizing Emergency Awakening to Audible Smoke Alarms: an update

This review examines research on what types of emergency signal will be the best to awaken most individuals and what can be improved. Four key areas are reviewed: (a) the characteristics of four signals; (b) how human characteristics alter arousal to different signals; (c) research comparing the effectiveness of different alarms in different sleeping populations; and (d) acoustical, methodological and theoretical implications