User's Manual

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Version 1.4
Figure 13 Graph selection for leak score
The histogram is the graphical display of a frequency distribution of the
measured sound level.
Figure 14 Logger Histogram
During noise monitoring, the noise level is repeatedly measured in intervals
of a few seconds. During a two-hour measurement period (e.g., from 2 a.m.
to 4 a.m.), more than 1000 individual measurement values may be
collected in some cases. The sound level is measured in dB. If, for
example, the sound intensity of 15 dB is measured 120 times, this sound
intensity has a frequency value of 120. Other sound intensity values are
measured with a different frequency. If all of these frequencies are plotted
as y values against a scale of the various dB sound intensities (x axis), one
obtains the so-called histogram as a frequency distribution.
This histogram is a representation of the noise distribution in the measured
period of time. The curve has a maximum, which represents the most
frequently measured noise sound intensity.
Histogram