AS NZS 2107:2016 pdf free.Acoustics—Recommended design sound levels and reverberation times for building interiors.
4 DEFINITIONS
For the purpose of this Standard, the definitions in IEC 60050-801 and those below apply.
4.1 A-weighted sound pressure level (L.)
The level of the frequency A-weighted sound pressure, as determined by an integrating- averaging sound level meter complying with AS IEC 61672.1.
4.2 Background sound level
The background sound level is defined as the LACq,I level with the space unoccupied but ready for occupancy.
NOTE: Australian users of this Standard should note the term ‘background A-weighted sound pressure level’ has a different defined meaning for environmental purposes under the AS 1055 series. New Zealand users should note ‘background sound level’ has a different defined meaning in NZS 6801 and other Standards related to environmental noise.
4.3 Equivalent continuous A-weighted sound pressure level (Leq.t)
The value of the A-weighted sound pressure level of a continuous steady sound that, within the measurement time interval, t, has the same mean square sound pressure as a sound under consideration whose level varies with time.
4.4 Design sound level
The sound levels given in this Standard are for the design of spaces in buildings.
NOTE: Sound levels within the given ranges have been found to be acceptable by most people for the space under consideration. When the sound level is greater than the upper level of the range most people occupying the space will become dissatisfied with the level of sound. When the sound level is below the lower level of the range, the inadequacy of background sound to provide masking sound can become problematic, for example, by allowing other intermittent noise sources to cause distraction, annoyance, or lack of privacy (see Clause 5.3).
4.5 Quasi-steady-state sounds
Sounds whose average characteristics substantially represent a steady-state sound.
4.6 Reverberation time (1)
The reverberation time of an enclosure, for a sound of a given frequency or frequency band, is the time that would be required for the reverberantly decaying sound pressure level in the enclosure to decrease by 60 decibels.
4.7 Steady-state sounds
Sounds whose average characteristics remain relatively constant in time.
5 RECOMMENDED DESiGN SOUND LEVELS AND REVERBERATION TIMES
5.1 Design sound levels for different areas of occupancy in buildings
The recommended ranges for design sound levels are given in Table 1. The levels are given as equivalent continuous A-weighted sound pressure levels measured in decibels.
NOTES:
1 For air-conditioning or plant noise with excessive low frequency energy (<200 lIz) due to turbulence (rumble), significant annoyance can arise even when the A-weighted sound pressure level is below the recommended range. See Clause 6. I .7.
2 The level of background sound may affect speech communication, recording, and in extreme conditions, the effectiveness of a public address system. Control of the background sound level is required to achieve good communications.
3 Spaces such as open plan and closed cell offices benefit from some continuous background sound or acoustic masking, which assists in providing acoustic separation, speech privacy, and reducing speech distraction.AS NZS 2107 pdf download.