The master thesis researches the unsatisfactory acoustic environment of day care facilities which often have too long reverberation times. Consequently, the learning process cannot be executed in the most optimum way, while the high noise levels also negatively affect the health of staff and children.
We approached the problem by developing prototypical sound absorbers customized for implementation in day care facilities. Such elements have to meet the statutory requirements for construction products as well as be appropriate in regards to health, economics and creativity. Working methods include calculations, laboratory measurements of absorption coefficient, in-situ measurements of reverberation time and equivalent sound pressure level and personal communication with the staff.
Five types of prototypical absorbers were made, varying by their design and position in the room and a computer program was created for calculating the needed absorptive surface. In-situ measurements performed before and after acoustical refurbishment of a playroom showed a notable improvement of acoustical properties of the room after the renovation. Mid-frequency reverberation time was reduced for almost 44% from 0,92 s to 0,52 s, while equivalent sound pressure level dropped for approximately 2,5 dB.
Effectiveness of the acoustical refurbishment was also measured by the staff’s subjective opinion, which was obtained in the form of personal communication and a questionnaire. The staff was delighted with the improvements, they believe the space to be much quieter and the sound absorbers unobtrusive.
The criteria relevant for deciding on a most appropriate acoustical element for the specific environment is presented in the conclusion.
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