Page 12 - Special Issue
P. 12

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.
The authors are grateful to the research team members from the University of Nebraska-Lincoln for their assistance with collecting and analyzing data ( This study was supported by United States Environmental Protection Agency Grant R835633.
American National Standards Institute (ANSI). (2002). S12.60-2002 Acoustical Performance Criteria, Design Requirements, and Guidelines for Schools. Acoustical Society of America, Melville, NY.
American National Standards Institute/Acoustical Society of America (ANSI/ASA). (2010). S12.60-2010 Acoustical Performance Criteria, De- sign Requirements, and Guidelines for Schools, Part 1: Permanent Schools. Acoustical Society of America, Melville, NY.
American Speech-Language-Hearing Association. (1995). Guidelines for acoustics in educational environments. American Speech-Language-Hear- ing Association 37, Suppl. 14, 15-19.
Astolfi, A., and Pellerey, F. (2008). Subjective and objective assessment of acoustical and overall environmental quality in secondary school class- rooms. The Journal of the Acoustical Society of America 123, 163-173.
Bistafa, S. R., and Bradley, J. S. (2000). Reverberation time and maximum background-noise level for classrooms from a comparative study of speech intelligibility metrics. The Journal of the Acoustical Society of America 107, 861-875.
Bottalico, P., Astolfi, A., and Hunter, E. J. (2017). Teachers’ voicing and si- lence periods during continuous speech in classrooms with different re- verberation times. The Journal of the Acoustical Society of America 141, EL26-EL31.
Bradley, J. S. (1986). Speech intelligibility studies in classrooms. The Journal of the Acoustical Society of America 80, 846-854. https://doi. org/10.1121/1.393908.
Bradley, J. S., and Sato, H. (2008). The intelligibility of speech in elementary school classrooms. The Journal of the Acoustical Society of America 123, 2078-2086.
Bronzaft, A. L. (1981). The effect of a noise abatement program on read- ing ability. Journal of Environmental Psychology 1, 215-222. https://doi. org/10.1016/S0272-4944(81)80040-0.
Brumm, H., and Zollinger, S. A. (2011). The evolution of the Lombard ef- fect: 100 years of psychoacoustic research. Behaviour 148, 1173-1198.
Crandell, C. C., and Smaldino, J. J. (2000). Classroom acoustics for children with normal hearing and with hearing impairment. Language, Speech, and Hearing Services in Schools 31, 362-370. 1461.3104.362.
Hodgson, M. (1999). Experimental investigation of the acoustical charac- teristics of university classrooms. The Journal of the Acoustical Society of America 106, 1810-1819.
Hodgson, M., and Nosal, E. M. (2002). Effect of noise and occupancy on optimal reverberation times for speech intelligibility in classrooms. The Journal of the Acoustical Society of America 111, 931-939. https://doi. org/10.1121/1.1428264.
Hodgson, M., York, N., Yang, W., and Bliss, M. (2008). Comparison of predicted, measured and auralized sound fields with respect to speech intelligibility in classrooms using CATT-Acoustic and ODEON. Acta Acustica united with Acustica 94, 883-890. AAA.918106.
Howard, C. S., Munro, K. J., and Plack, C. J. (2010). Listening effort at signal- to-noise ratios that are typical of the school classroom. International Journal of Audiology 49, 928-932.
Hunter, E. J., and Titze, I. R. (2010). Variations in intensity, fundamental frequency, and voicing for teachers in occupational versus nonoccupa- tional settings. Journal of Speech Language and Hearing Research 53, 862- 875.
  12 | Acoustics Today | Spring 2020, Special Issue 20 | Acoustics Today | Fall 2018
Reprinted from volume 14, issue 3

   10   11   12   13   14