- 72 ADA accessible design standards
- 73 Ergonomics: visual and physical
- 74 Exterior noise intrusion
- 75 Internally generated noise
- 76 Thermal comfort
- 77 Olfactory comfort
- 78 Reverberation time
- 79 Sound masking
- 80 Sound reducing surfaces
- 81 Sound barriers
- 82 Individual thermal control
- 83 Radiant thermal comfort
- P4 Impact reducing flooring
78. Reverberation time
Reverberation time, or RT60, is a metric which describes the length of time taken for a sound to decay by 60 dB from its original level. Optimal reverberation times vary depending on room volume, intended use of the space and the frequency of transmitted sound. In spaces with high reverberation times, the sounds of voices and footsteps take longer to dissipate, contributing to higher levels of ambient noise. The noise produced by reverberation can decrease speech intelligibility and in some situations cause additional stress.
This feature seeks to establish lower reverberation time to help maintain comfortable sound levels. This performance specification can be met through the use of sound-absorbing materials on various surface and design elements.
The following spaces have maximum reverberation time (RT60) as described:
Reverberation time measurements for learning spaces meet the following criteria:
|Core & Shell||New & Existing Buildings||New & Existing Interiors|
|Part 1: Reverberation Time||-||O||O|
|Part 2: Reverberation Time for Learning Spaces||-||-||-|
|Commercial Kitchen||Education||Multifamily Residential||Restaurant||Retail|
|Part 1: Reverberation Time||-||-||-||-||-|
|Part 2: Reverberation Time for Learning Spaces||-||O||-||-||-|
Verification Methods Matrix
|Letters of Assurance||Annotated Documents||On-Site Checks|
|Part 1: Reverberation Time||Performance Test|
|Part 2: Reverberation Time for Learning Spaces||Performance Test|
The General Services Administration's Sound Matters recommends RT60 of 0.6 seconds for meeting rooms.
ANSI/ASA S12.60-2010 Part 1 recommends maximum permitted reverberation times for core learning spaces of less than or equal to 10,000 ft³ to be 0.6 seconds.
ANSI/ASA S12.60-2010 Part 1 recommends maximum permitted reverberation times for core learning spaces greater than 10,000 ft³ and equal to or less than 20,000 ft³ to be 0.7 seconds.