Applicability Of Acoustic Capacity In Regulations Based On Study Of Noise Enviroment In Danish Nusery Schools

The room acoustics of 20 nursery school rooms in day-cares (age 0.5-2.5 years) or pre-schools (age 2.5-6.0 years) were investigated by means of reverberation time measurements according to 3382-2:2008, registration of significant acoustical surfaces and noise sources, and interviews. The investigations were part of a project run by The Danish Ecological Council including 20 nursery schools representative for the current Danish building stock, that investigates numerous indoor climate parameters. In Denmark reverberation time according to building code is argued to relate to acceptable noise environment in nursery schools [1]. Although most rooms lived up to building code, interviews of employees indicate noise problems still exist. Observations showed that, there were relations between ceiling types and how fast reverberation time increases with volume. The smallest and largest rooms had seldom wall absorbers, whereas mid-size rooms often had wall absorbers. This lead to investigations of acoustic capacity in the rooms similar to the suggestions by Rindel for restaurants [2]. Conservative estimates of Lombard effect of small children and number of "talkers" were made for the basis of ranges for appropriate reverberation time vs. m3/child. It was found that a large majority of rooms did not have sufficient conditions and almost none fit the criterion for satisfactory acoustic capacity.