Operation; Measurement Conditions; Background Noise; Interference - AEMC CA832 User Manual

4.1

Measurement Conditions

4.1.1

Background Noise

If the difference in levels between the absence and the presence of noise
to be measured is 10dB or more, the influence of background noise on the
measurement may be considered negligible.
If the difference is lower at this level, a compensation correction (see table
below) must be applied to the measurement performed to integrate the
background noise:
Level Difference (dB)
Compensation Value (dB)
4.1.2

Interference

The microphone must be positioned far from any sound reflective surfaces
such as walls or the ground, to minimize errors due to possible noise inter-
ference.
When taking measurements, hold the sound level meter at arm's length to
avoid any reflections due to your own body and also to enable free propa-
gation of sound in all directions.
Take the necessary steps so that no obstacle is between the measure-
ment point and the noise source.
Disregard the extremely low readings (insignificant sound) or conversely
those at the top of the scale (overload).
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CHAPTER 4

OPERATION

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Sound Level Meter Model CA832
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