SoundAdvisor Model 831C
Understanding the Overall Tab
4-12
The Community Noise page displays the values LDN and LDEN which are
commonly used to evaluate community noise. Since community noise
metrics are based upon a full day, measurements shorter than 24 hours do
not present valid data for this metric.
TAKE NOTE
The metric CNEL is equivalent to LDEN.
Metrics shown here are dependent on the number of Day, Evening, and Night
hours, which you set in the measurement setup file.
Understanding LDEN
Although the standard ISO 1996-2:2007 specifies default values used in the
calculation of LDEN, in practice the time values defining the day, evening and
night periods may be changed, as permitted by Directive 2002/49/EC of the
European Parliament and of the Council of 25 June 2002 relating to the
assessment and management of environmental noise. It is important to
verify prior to the measurement that the values have been properly defined
for your purposes.
4.2.10 About the C Minus A Impulsivity Page (Overall Page)
FIGURE 4-19
The “C minus A” metric provides an indication of the low
frequency content of noise measured. This is done by
subtracting the A-weighted equivalent level from the C-
weighted equivalent level.
1.
The integrated levels for L
Aeq
are always calculated using
the linear detector, regardless of the value selected in the SLM
Setup. The L
AIeq
value is from the impulse detector.
4.2.11 About the TA-Lärm Page (Overall Page)
This metric is primarily used in Germany. To turn off this display, or any other
display that is not related to your measurement, see
.
4.2.12 About the Sound Exposure Level Page (Overall Page)
This page is primarily used for the practice of industrial hygiene.
1.
