Assessing Acoustic Conditions in Hybrid Classrooms with COVID-19 Social Distancing at the University of Sharjah

Abstract

In response to COVID-19 global pandemic, the University of Sharjah (UAE) implemented a flexible hybrid teaching approach where the capacity of the classrooms is reduced to 50% and installed additional audiovisual equipment to support the hybrid teaching model. The aim of this study is to assess the acoustic parameters in the hybrid classrooms with focus on reverberation time, sound clarity (C50) and strength (G). Measurements were taken in six different classrooms using sound analyzer and ROOM EQ Wizard software in accordance to the guidelines set by ISO 3382. In addition, we compared the experimental data with that obtained from Sabine's diffuse field theory and from a model developed by E. Nilsson, which considers the absorption in classrooms to be mainly due to the absorbing ceilings. Reverberation times results show that Leq (dBA) to vary from 43.0 - 50.9 dBA for acoustically untreated classroom, and 32.3 for classrooms with the air condition off. Results obtained from the theoretical model showed the same overall behavior over the investigated frequency range. Sound clarity and strength measurements indicated that the acoustic conditions in hybrid classrooms do not satisfy the international standards with the exception of one classroom, which was acoustically treated.