Interior surface treatment guidelines for classrooms according to the acoustical performance criteria

Title & Authors
Interior surface treatment guidelines for classrooms according to the acoustical performance criteria
Ryu, Da-Jung; Park, Chan-Jae; Haan, Chan-Hoon;

Abstract
There are many results in which acoustical conditions of a classroom play an important role for studying effects and academic achievement of students. However, there are very few guidelines or design proposals which could make appropriate acoustic environment when classrooms are built or renovated. The present study suggests various design proposals satisfying acoustic standards of classrooms based on theoretical calculation and acoustic field experiments. At first, minimum area of sound absorption was calculated which is required to satisfy the acoustic standard for domestic middle and high schools. Also, room acoustic measurements were carried out in order to investigate the acoustic performance of an existing classroom by changing interior finishing materials on ceiling and rear walls. As a result, it was revealed that reverberation time standard below 0.8 s can be acquired even if there is no sound absorption on ceiling which is a general practice executed in Korea. Specially, it was found that if partial area of ceiling would be treated as reflective with the ratio of sound absorption and reflection as 2:1, almost similar acoustic parameters of $\small{C_{50}}$, $\small{D_{50}}$, RASTI (Rapid Speech Transmission Index) and higher sound levels could be acquired in comparison with the case of entire sound absorption on ceiling.
Keywords
Classroom;Interior acoustic criteria;Sound absorptive area;Reverberation time;Sound pressure level;Speech intelligibility;Rapid speech transmission index;
Language
Korean
Cited by
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