ISO 10052:2021 pdf download – Acoustics — Field measurements of airborne and impact sound insulation and of service equipment sound — Survey method. No correction for background noise shall be applied. For measurements of the airborne sound insulation between rooms and the airborne sound insulation of façades using the loudspeaker method, the sound power of the source should be adjusted so that the sound pressure level in the receiving room (in each frequency band) is at least 6 dB higher than the background noise level. This shall be checked by switching the source on and off before starting the measurement....