Sound insulation and reverberation time for classrooms - Criteria in regulations and classification schemes in the Nordic countries

Acoustic regulations or guidelines for schools exist in all five Nordic countries. The acoustic criteria depend on room uses and deal with airborne and impact sound insulation, reverberation time, sound absorption, traffic noise, service equipment noise and other acoustic performance characteristics. In four of the countries – Finland, Iceland, Norway and Sweden – schools are also included in voluntary classification schemes published as the national standards SFS, IST, NS and SS. These classification schemes have four quality levels with the same denotations A, B, C and D, but otherwise not identical. The national criteria for quality level C correspond to the national regulations or recommendations for new-build. The quality levels A and B are intended to define better acoustic performance than C, and D lower performance. Typically, acoustic regulations and classification criteria for schools have become more extensive and stricter during the last two decades.
The paper focuses on comparison of sound insulation and reverberation time criteria for classrooms in regulations and classification schemes in the Nordic countries. Limit values and changes over time will be discussed as well as how the role of classification schemes could be optimized in the future.