What is ISO 10140-4 about?
ISO 10140-4 is the fourth part of multiple series that specifies the basic measurement procedures for airborne and impact sound insulation of building elements in laboratory test facilities.
ISO 10140-4 provides all the basic measurement techniques and processes for measurement according to ISO 10140‑2 and ISO 10140‑3 or facility qualifications according to ISO 10140‑5.
Who is ISO 10140-4 for?
ISO 10140-4 on acoustics laboratory measurement of sound insulation of building elements is useful for: 
- Acoustic laboratory  
- Construction industry 
- Civil engineer 
- Building contractor 
- Manufacturer of industrial production 
- Investigator of acoustic 
- Land surveyor of acoustic 
Why should you use ISO 10140-4?
The excitation of the room modes is highly dependent on the source locations. The sound reduction index depends strongly on which room modes are excited. Even if the repeatability is satisfactory at low frequencies, the reproducibility and comparability with test results from other rooms can be very poor and the test results become dependent on the test facility.
In order to reduce the spread of the measured results, additional effort is necessary with regard to the excitation and sampling of the sound field in the rooms and the special requirements that the rooms have to meet.
ISO 10140 (all parts) helps you to improve the layout for laboratory measurements, ensure consistency and simplify future changes and additions regarding mounting conditions of test elements in laboratory and field measurements. ISO 10140 (all parts) aims at presenting a well-written and arranged format for laboratory measurements.
ISO 10140-4 aids you with procedures to determine the impact of sound insulation using sound pressure measurements with an impact source operating on a floor or stairs in a building with low-frequency bands.  In low-frequency bands (below 400 Hz in general and especially below 100 Hz), the sound field in the test rooms is not diffuse, especially when room volumes of only 50 m3 to 100 m3 are considered.
What’s changed since the last update?
BS EN ISO 10140-4:2021 supersedes BS EN ISO 10140-4:2010 which is withdrawn.
The main changes compared to the previous edition are as follows: 
- All references in the text have been updated
- In clause 2, the normative references have been updated
- In clause 3, the terms and definitions have been updated
- In 4.8 first and last paragraphs have been edited
