We have a library that is roughly 40,000cf which requires us to determine maximum reverberation from NRC-CNRC Construction Technology Update No. 51, Acoustical Design of Rooms for Speech (2002) - figure 3. Based on this standard, a 0.7 reverberation time is required. After review of the architectural drawings this seems almost impossible, even with use of acoustical ceiling + wall panels. Btw, the min reverberation time was cut in half since v2009! Anyone have any tips for meeting such a low reverberation time???!!! Thanks!