Conference room/Group study room (<100 m²)
In this type of room people usually work in groups gathered around a table. Verbal communication takes place in all parts of the room, which makes speech intelligibility vital throughout the room.
Reverberation time of 0.5 seconds. To achieve this, a full acoustic ceiling is needed of sound absorption class B (in accordance with EN ISO 11654).
If the conference room is larger than 100 m², reflectors may be necessary in the central part of the ceiling. In larger group study rooms occupied by two or more groups, screens/partitions should be used to divide the groups both acoustically and visually.
Building codes and standards
UK regulations, Building Bulletin 93 (BB93), states that in primary schools an unoccupied mid frequency (Tmf) reverberation time of <0.6 seconds be achieved in these areas. In secondary schools it states that an unoccupied mid frequency (Tmf) reverberation time of <0.8 seconds be achieved. If the room is designed specifically for the teaching of hearing impaired pupils then an unoccupied mid frequency (Tmf) reverberation time of <0.4 seconds is required.
Swedish Standard 02 52 68 recommends a reverberation time of 0.5 or 0.6 seconds, depending on the selected quality level. This applies to normally furnished but unoccupied rooms. The above figure is the highest recommended value for the frequency range 250 - 4,000 Hz. At 125 Hz a value 20% higher is permitted.