An Assessment of Different Sized Open Plan and Enclosed Kindergarten Classroom Listening Environments

Open plan classrooms, where several class bases share the same space, have recently re-emerged in Australian primary schools. This paper compiled the results of three recent studies to compare both the acoustic parameters and speech perception test results in four different Kindergarten classrooms (an enclosed classroom with 25 students, a double classroom with 44 students, an untreated linear fully open plan triple classroom with 91 students, and a purpose-built semi-open plan K-6 classroom with 205 students) with the children’s ratings about how well they could hear their teacher. Compiling these results allowed a regression analyses to be undertaken to establish the acoustic limits needed for children to rate they could hear their teacher ‘well’ (here defined as the ‘hear well’ criteria). Ambient noise levels, intrusive noise levels, and teacher’s speech levels were recorded during different activities and room impulse responses were recorded for different teaching scenarios. From these recordings average noise levels, signal-to-noise ratios, speech transmission index scores, and reverberation times were calculated. These parameters were compared to the current Australian/New Zealand acoustic standards for classrooms (AS/NZS2107:2000), the acoustic recommendations in the literature for classrooms with 5-6-year-old children, and the derived ‘hear well’ criteria. The results revealed much higher intrusive noise levels in the two largest open plan classrooms (especially the untreated triple classroom), resulting in signal-to-noise ratios and speech transmission index scores to be well below the ‘hear well’ criteria. Results from the speech perception task also revealed poorer scores and slower response times in the triple open plan classroom compared to the other classrooms. Additionally, children’s speech perception abilities decreased the further away they were seated from the teacher in the classrooms with higher noise levels resulting in scores outside the ‘hear well’ criteria. These results suggest students may have difficulty listening and learning in open plan classrooms and teachers are likely to strain their voice from needing to speak above a comfortable level to be heard. Additionally, the regression analysis results from the children’s questionnaires confirmed that the acoustic recommendations suggested in the literature need to be met in order for the children to be able to hear their teacher ‘well’. These results suggest that it may be beneficial for Australia to implement acoustic standards for unoccupied and occupied classrooms and have enforced