Product Noise

Product noise evaluation may be a legal requirement, to drive quality or other design criteria. For example, certain types of outdoor machinery are regulated to control the noise they produce in order to reduce its environmental impact. 

Usually the Sound Power of the device is required and in it's simplest terms this can be derived from a series of Sound Pressure measurements at known distances. The testing environment however plays a critical role.

The Sound Intensity technique is another way to establish the Sound Power value but this requires more sophisticated instrumentation.

Applicable Guidance:

ISO 3744:2010
Acoustics — Determination of sound power levels and sound energy levels of noise sources using sound pressure — Engineering methods for an essentially free field over a reflecting plane

ISO 9614-3:2002
Acoustics — Determination of sound power levels of noise sources using sound intensity — Part 3: Precision method for measurement by scanning

ISO 3746:2010
Acoustics — Determination of sound power levels and sound energy levels of noise sources using sound pressure — Survey method using an enveloping measurement surface over a reflecting plane

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