Page 12 - Special Issue

Building a Sound Future for Students
to individual work to small group activities. Each of these types of activity in an occupied active classroom results in varying noise levels produced by the occupants themselves.
Shield et al. (2015) have analyzed the relationship between occupied and unoccupied noise levels in secondary classrooms. They conducted an acoustic survey of 185 unoccupied secondary school classrooms in England and performed continuous monitoring during 247 occupied core subject lessons in 80 of those classrooms. Results confirmed that the observed noise levels during these lessons in the occupied active classroom increased with the number of students and was greater for rooms with younger students. Consistent with the Shield and Dockrell (2008) study, a significant relationship was found between the sound levels gathered during lessons (occupied active) and those gathered in unoccupied conditions. Data on student learning outcomes are not shown in the Shield et al. (2015) paper though. More analyses comparing student achievement against occupied versus unoccupied noise levels are needed, as presented by Shield and Dockrell (2008). If the levels in occupied active classrooms more strongly predict student learning outcomes than in unoccupied levels, then design standards should include some guidance, perhaps for noise levels in occupied active classrooms as well as for ways to achieve those recommendations to optimize student learning.
Steady-state noise sources like HVAC noise can be easy to quantify, predict, and measure, but it is important to acknowledge that other, often times less predictable, sources of sound and noise exist in occupied active classrooms and can detrimentally interfere with communication between teacher and student. Considerations for occupied active conditions in classrooms and how they differ from unoccupied conditions need to be thought of holistically. Ongoing research in this area will hopefully give us a better understanding of how all of the environmental conditions work together to affect student achievement.
Acknowledgments
The authors are grateful to the research team members from the University of Nebraska-Lincoln for their assistance with collecting and analyzing data (engineering.unl.edu/healthy-schools). This study was supported by United States Environmental Protection Agency Grant R835633.
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12 | Acoustics Today | Spring 2020, Special Issue 20 | Acoustics Today | Fall 2018
Reprinted from volume 14, issue 3