The goal of this research is to verify the pressure of noise levels in classrooms and its interference on the intelligibility of teachers' speech. The methodology used was of a descriptive and exploratory, quali-quantitative nature undertaken in stages, namely: 1) Evaluation of the comfort/discomfort; 2) Acoustic evaluation and 3) vocal performance evaluation. The findings showed that 94.6 per cent of the teachers said that is necessary to raise the tone of voice for speech to be intelligible; the level of noise pressure varied between a minimum of 46.60 dB (A) and a maximum of 87.90 dB (A); and the vocal performance of the teachers ranged between 49.01 and 83.75 dB (A). It concludes that poor acoustics obliges teachers to speak more strenuously, which causes fatigue in the teachers' speech. The cause of this situation is linked to the internal and external sources and the excess of students in classrooms.
Intelligibility of speech; noise; teacher; acoustic; vocal performance
