ASA - ANSI/ASA S12.9 PART 3
American National Standard Quantities and Procedures for Description and Measurement of Environmental Sound – Part 3: Short-term Measurements with an Observer Present
|Publication Date:||15 January 2013|
The scope of this standard includes the measurement, with an
observer present, of quantities such as equivalent-continuou
The purposes of this standard are to (a) specify procedures for measurement of environmental sound from a specific source or sources at a specified location, and (b) to specify procedures to effectively eliminate the contributions of extraneous background sounds from the source-specific measurements. Sound pressure levels are measured with an observer present to record the data described in this part.
This standard is applicable to the measurement of quantities
such as equivalent-continuou
1. Assessment of environmental sound
2. Measurement of source emissions as equivalent-continuou
3. Measurement of received sound as LEQ
4. Correction of LEQ measurements for the background sound
NOTE Source emissions typically are measured only when the direct measurement of the received sound is not practical or when the source is not yet in operation. In either case, the received sound must be predicted using the measured source emissions. Annex A contains an informative discussion regarding source emissions and received sound, and clause 7.4 discusses, in general terms, moving closer to the source when the source cannot be turned off, and, as a result of not being able to be turned off, correction for the background is problematic.