period three
Acoustical Analysis
notes
Setting a Design Goal
Figure 35
When defining the acoustical design goal for an outdoor environment, to meet a local noise ordinance for example, the A-weighted scale is typically used. This generally takes the form of a maximum A-weighted sound-pressure level at the lot line of the property.
More-sophisticated noise ordinances may specify maximum sound-pressure levels for each octave band and possibly a restriction on other characteristics of the sound. For example, a sound ordinance may define that a tone is present when the sound-pressure level in any one-third octave band exceeds the arithmetic average of the sound-pressure levels in the two neighboring one- third octave bands by 5 dB or more.
