Measuring low noise level in dwellings

Abstract

DS 490:2018 "Akustik - Lydklassifikation af boliger", translated to "Acoustics - Acoustic Classification of Dwellings" relates to many acoustical parameters, and two of them "Noise from ventilation" and "Reverberation times" are now being tested in real life in the Danish "Voluntary sustainability classification".(Called FBK) Danish building regulation state a sound level limit in dwellings from all kinds of technical systems at 30 dB(A), equal to the Acoustical class C, comparable with the limit in several countries. Research shows that 30 dB(A) does not ensure acoustic satisfying comfort for most people. The FBK have chosen to lower the noise limit to 25 dB(A), equal to acoustical class B. We need to improve the ventilation systems in order to reach such lower level of sound emission, and to be able to measure it implemented in dwellings. The paper describes some methods and in situ experience fighting background noise problems caused by activities around and in the dwelling, as well as in the measurement systems. Special analyses and editing of recordings based on listening and pragmatic judgements are relevant. The goal is: Measure and document low noise without a cost in time and money being a barrier for lower noise levels in dwellings.