Spratford Meredith, Walker Elizabeth A, McCreery Ryan W
Audibility, Perception, and Cognition Laboratory, Boys Town National Research Hospital, NE.
Wendell Johnson Speech and Hearing Center, Department of Communication Sciences and Disorders, The University of Iowa, Iowa City.
Am J Audiol. 2019 Dec 16;28(4):927-934. doi: 10.1044/2019_AJA-19-0041. Epub 2019 Nov 4.
Purpose Classrooms including children who are hard of hearing (CHH) may be modified to manage noise and reverberation and improve speech perception. Little is known about the acoustic characteristics of contemporary general education classrooms that include CHH compared to classrooms of typical peers. We proposed the following research questions about the acoustic environment of general education classrooms including CHH: (a) How reliable are acoustic measurements collected using an iOS device, application, and external microphone? (b) What proportion of classrooms meet the American National Standards Institute's standards for unoccupied noise levels and reverberation? Method A smartphone application was used to measure sound levels, reverberation, and clarity for 164 general education classrooms including CHH. Linear mixed models were used to examine the following: (a) reliability of acoustic measures made using an application and external microphone and (b) predictors of sound levels, reverberation, and clarity for elementary classrooms including CHH. Results Results indicate the application reliably measures classroom acoustics. Classrooms exceeded the American National Standards Institute's recommended noise levels, but met reverberation time guidelines. Grade; heating, ventilation, and air conditioning status; and room volume predicted classroom acoustics. Conclusions As a screening tool, the application was shown to be effective in reliably measuring reverberation and classroom noise levels. The high levels of noise in unoccupied classrooms indicate a need for increased use of noise abatement strategies and the use of remote-microphone systems, especially in classrooms where noise levels cannot feasibly be reduced. Using an application may be a cost-effective method for monitoring important acoustic features that impact children's ability to understand speech in the classroom.
目的 对于包含重听儿童(CHH)的教室,可以进行改造以控制噪音和混响,并改善言语感知。与普通同龄人所在的教室相比,对于当代包含重听儿童的普通教育教室的声学特性了解甚少。我们针对包含重听儿童的普通教育教室的声学环境提出了以下研究问题:(a)使用iOS设备、应用程序和外部麦克风收集的声学测量数据有多可靠?(b)符合美国国家标准学会未占用时噪音水平和混响标准的教室比例是多少?方法 使用一款智能手机应用程序测量了164间包含重听儿童的普通教育教室的声级、混响和清晰度。采用线性混合模型来检验以下内容:(a)使用该应用程序和外部麦克风进行声学测量的可靠性,以及(b)包含重听儿童的小学教室声级、混响和清晰度的预测因素。结果 结果表明该应用程序能够可靠地测量教室声学特性。教室的噪音水平超过了美国国家标准学会的推荐值,但混响时间符合指导标准。年级、供暖、通风和空调状况以及房间容积可预测教室声学特性。结论 作为一种筛查工具,该应用程序被证明能有效地可靠测量混响和教室噪音水平。未占用教室中的高噪音水平表明需要更多地采用降噪策略并使用远程麦克风系统,尤其是在无法切实降低噪音水平的教室。使用该应用程序可能是一种经济有效的方法,用于监测影响儿童在课堂上理解言语能力的重要声学特征。