Revision of standard S12.60 Part 1

The classroom acoustics standard ASA/ANSI S12.60 Part 1 is currently being revised. The document originally published in 2001 was updated in 2010 in an attempt to make the document easier to reference in building codes. It moved explanatory sections to informative annexes and revised some technical requirements to make it align with expectations of code officials. This was only partially successful and imposed some challenges. The current revision intends to bring the standard in closer alignment with current practice and updates some of the technical requirements included in the standard to be more technically accurate and implementable. For example, the previous reverberation time requirements limits are proposed to be revised to allow calculation of average absorption coefficients. The use of either calculations of average absorption or measurements of reverberation time would be allowed to show conformance. This change allows the limits based on room size to avoid discontinuities as room size changes as occurred in the previous method. The revision also proposes changes to the prescriptive sound isolation requirements used in the previous version. Both outdoor to indoor transmission and indoor sound transmission classes are considered, and methods of conformance by test are expanded and clarified.