LAUSR

Airborne sound isolation between spaces is determined not only by the direct sound transmission through the separating assembly, but also flanking transmission, which is the structureborne transmission of vibration due to acoustical excitation in the source room. In many cases, the flanking paths dominate, such as where the separating assembly has a high level of sound transmission loss, and the ability to calculate these paths is therefore crucial if the isolation is to be accurately predicted. Methods for calculating impact noise have been developed in Europe [standard EN ISO 12354] and are currently in use in Europe and Canada; however, the methods are not commonly known or used in the United States. The authors report on use of these methods in calculating flanking noise transmission in recent projects.