In this study, associations between classroom conditions and teachers' voce use were researched (N=40). Acoustic variables were reverberation time (T60), early decay time (EDT), sound strength (G), the ratio of early and late sound energy arriving to a listener (C50), the ratio of early arriving sound energy to overall sound energy (D50), speech transmission index (STI) and rate of spatial decay of sound pressure levels (DL2). Indoor climate was also evaluated. Voice variables measured were sound pressure level (SPL), fundamental frequency (Fo) and spectrum slope. According to findings when the values of T60, EDT and DL2 were lower or the values of C50, D50 and G higher, teachers' voice SPL was higher. When reverberation times were longer, F0 increased and when the values of C50 and D50 were higher, men's F0 was higher. Poor indoor air increased occurrence of laryngitis. The results showed that indoor environment affects voice use and thus, is associated with the health of voice organs.
Rantala, L., & Sala, E. (2015). Associations between classroom conditions and teacher’s voice production. In Energy Procedia (Vol. 78, pp. 3120–3125). Elsevier Ltd. https://doi.org/10.1016/j.egypro.2015.11.767