Arianna Astolfi
Arianna Astolfi, from researcher in Building Physics and building services at Politecnico di Torino, Italy, was presenting the results on speech intelligibility and measurements performed in a primary laboratory-classroom before and after a sound absorption acoustical treatment.
She concluded that the correlation between speech intelligibility and objective parameters are obtained for children of different age and also that the intelligibility decreases due to the reverberation.
The laboratory-classroom was provided with a sound absorption suspended ceiling and also a reflective ceiling in the central part. Due to this the volume went from 215 to 195 m3. They also used the backwall by placing mineral wool panels and covering the lower part of the backwall with plasterboard. The result of this treatment was that the occupied midfrequency reverberation time (RT) was decreasing from 1,6 s to 0,4 s. They performed over 1600 tests on 200 students, from age of 6 to 11, before and after the acoustical treatment. During the test they added simulated traffic noise from an external source and impact noise was generated on the floor above the classroom.
They found that the correlation between speech intelligibility and objective parameters are obtained for children of different age and also that the intelligibility decreases due to the reverberation.
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