MVA 02 rev 5 - December 2017
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Fig. 3-13 Positions of measurement microphones
Reference standards
EN ISO 3744 - Determination of sound power levels of noise sources using sound pressure (engineering
method in an essentially free field over a reflecting plane).
EN ISO 3746 - Determination of sound power levels of noise sources using sound pressure (survey method
using an enveloping measurement surface over a reflecting plane).
ISO 13347 - Industrial fans - Determination of fan sound power level under standardized laboratory
conditions.
MICROPHONE POSITION
Measurements external to ducts