The new standard ISO 3382-3: Acoustics — Measurement of room acoustic parameters — Part 3: Open plan offices, has now officially been approved and moved on to publication stage 60.00 (2011-12-19), which categorises it as an international standard under publication.
The main points of this standard as experienced by Acoustic Bulletin, is the fact that reverberation time is not included, as it is not regarded as a trustworthy quality in open space environments. Instead qualities related to the distance the sound travels are introduced.
Instead of reverberation time, several more relevant acoustic qualities, including spatial sound distribution, spatial decay, sound pressure level at distance, and sound transmission index, are measured and can be converted into 4 single number quantities: distraction distance, spatial decay rate of A-weighted SPL of speech, A-weighted SPL of speech at 4 m, and average A-weighted background noise level.
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