EN 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

From household appliances such as washing machines and fridges to engineering equipment and sub-assemblies, this test is used to measure the inherent sound power output level of a device in a free field environment. Measurements made to this standard are conducted in specialist test chambers which prevent unwanted acoustic reflections being measured along with the noise output of the device under test or in free-field outdoor test environments. SATRA’s purpose-built hemi-anechoic chamber is designed to significantly attenuate background noise, to prevent any acoustic interference from external sources. Tests to these standards achieve Engineering Grade accuracy (Grade 2).