Universal acoustic design for schools: An evidence based approach

Abstract

A universal acoustic design framework for mainstream schools is proposed to provide an inclusive listening environment, considering students’ diverse hearing and communication needs. Census data in England and Wales reveals that 8% of pupils have special hearing and communication needs (SHCN), with speech, language and communication needs being most prevalent, followed by autistic spectrum disorder. A further 3% have social, emotional and mental health needs which should be included in the SHCN definition. SHCN pupils plus young children and children with English as an additional language are detrimentally affected by classroom noise and hence require better acoustic conditions than other pupils.

Analysis of speech perception studies quantifies the listening disadvantage faced by students with different needs. The disadvantage is largest for students with severe-to-profound hearing loss, while other needs show negligible or minor inherent disadvantage in quiet acoustic conditions but significant disadvantage in noisy active classrooms.

Considering practical design constraints, the paper proposes “reasonably adjusted” criteria of 0.5 s RT (occupied) and 35 dBA ambient noise level to minimise disadvantages for students with SHCN. Analysis of school acoustic data from a previous study confirms that these criteria would control buildup of noise in active classrooms, thus reducing impact on learning tasks and cognitive performance. A theoretical model demonstrates that these criteria would achieve target levels for signal-to-noise ratio and speech clarity.

The paper recommends a holistic approach combining acoustic design with assistive technology and classroom management strategies to meet the needs of all students, minimizing impacts on learning.