NTi Audio XL2 Sound Level Meter - Manual (Page 237)

237
Appendix
LAFmin dt Minimum Sound Pressure Level “delta t” in report
Minimum level of the preset logging interval in the LOG-menu,
e.g. 1 second.
LAFxx% Percentile Sound Level
The statistical distribution of sound pressure levels is commonly
used for environmental noise analysis, such as road traffic or com-
munity noise assessments. For example LAFxx% is the noise
level exceeded during xx% of the measurement period; e.g.,
LAF90% is the noise level exceeded during 90% of the measure-
ment period.
Please see the specifications at chapter Technical Data XL2: Func-
tions of Extended Acoustic Pack (optional) in this manual.
90
80
70
60
Time [seconds]
Sound Level [dB] vs Time
LAF10% = 88.8dB
LAF50%= 76.4dB
LAF90%= 66.6dB
LAeq= 84.2dB
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