Assessment of Acoustic Quality in Classrooms Based on Measurements, Perception and Noise Control

Abstract

Education plays a fundamental role in the formation of modern society. The importance of education for humans is expressed thus by renowned Brazilian educator Paulo Freire1: “The fountainhead of man’s hope is the same as that of his educability: the incompleteness of his being of which he has become aware. It would be a sorry contradiction if, incomplete and aware of this incompleteness, man were not engaged in a permanent process of hopeful search. This process is education.” (Freire, p 114)1 The long and arduous process of individual and collective education takes place primarily in classrooms. It is here that contact is established between teachers and students and between individual students and their peers. It is here that knowledge is transmitted in its most ancient form, i.e., through oral communication. The quality of this communication, and ultimately, of classroom education itself, is closely linked to the acoustic quality of the classroom. This acoustic quality can be characterized based on the reverberation time, speech transmission index, sound insulation, and the noise levels inside and outside the classroom2-5. High noise levels in the classroom impair oral communication, causing students to become tired sooner more often, and this premature fatigue tends to have a negative effect on their cognitive skills6. The reason for the existence of acoustic problems in classrooms, according to Seep7, is not a lack of knowledge about how to solve the problem, but primarily a lack of sensitivity of the professionals involved, both in the field of teaching and that of classroom design, to solve the problem. The problem of acoustic quality in a classroom begins in its design phase and extends all the way to the final quality of the education provided in public and private schools, primary and secondary schools, and in universities. Many of the aspects that appeared with the evolution of the modern era served to deteriorate the acoustic environment of the classroom. A reflection of our times is the fact that practically every student owns a mobile phone, a digital player, and other electronic devices that tend to render the school environment noisy, hindering its core purpose. Hagen6 believe that the school environment should promote an atmosphere that encourages everyone’s interest in listening and being involved in communication. An acoustically