Acoustical Design Criteria, Definitions and Justification
In the past, acoustical design criteria for educational facilities were derived from the information in various published acoustical texts and papers, many years of experience and past practice, as well as accepted industry standards. In 2002, the American National Standards Institute (ANSI) officially adopted a standard for the acoustical performance criteria, design requirements and guidelines for schools which was developed by the Acoustical Society of America (ASA). This standard, known as ANSI S12.60, is a comprehensive summary of the various acoustical factors which have been shown to influence learning. The standard includes definitions of terms, recommended design goals and testing protocols for pre- and post- installation acoustical measurements. This standard has been officially adopted by the New Jersey School Construction Company (NJ SCC) as the required minimum acoustical design criteria and is incorporated in their Design Manual.
The overall goal in the past and present is to facilitate teaching and learning by creating an acoustical environment with sufficiently low background noise and high speech intelligibility. Effective verbal communication with a high degree of speech intelligibility is achieved when the teachers’ “signal” or voice is sufficiently greater than the background “noise,” generated externally or internally, within a classroom. The ANSI standard predicates that following its recommended design goals will achieve a signal to noise ratio of 15 dB. Since the volume or level of speech is not within the control of the school designers, the acoustical design is based on reducing the background noise in the classrooms. This is accomplished by reducing the noise transmitted through school building partitions, the noise produced by mechanical systems, and absorbing or dissipating noise within the school’s core and ancillary learning spaces. More information on this standard is available at the ASA website: 
The full text of the standard may now be downloaded free of charge at: =ASA