ISO 10848 specifies measurement methods to be performed in a laboratory test facility or in the field in order to characterize the flanking transmission of one or several building components. This part of ISO 10848 specifies laboratory and field measurements of buildings for Type B elements (defined in ISO 10848-1) when the junction has a substantial influence. Laboratory measurements are used to quantify the performance of the junction with suppressed flanking transmission from the laboratory structure. Field measurements are used to characterize the in situ performance and it is not usually possible to suppress unwanted flanking transmission; hence the results can only be considered representative of the performance of that junction when installed in that particular building structure. This part of ISO 10848 is referred to in ISO 10848-1, 4.5, as being a supporting part to the frame document and applies to Type B elements that are structurally connected as defined in ISO 10848-1. The measured quantities can be used to compare different products, or to express a requirement, or as input data for prediction methods, such as ISO 12354-1 and ISO 12354-2. The relevant quantity to be measured is selected according to ISO 10848-1, 4.5. The performance of the building components is expressed either as an overall quantity for the combination of elements and junction (such as Dn,f,ij and/or Ln,f,ij and/or Lne0,f,ij) or as the normalized direction-average velocity level difference Dv,ij,n of a junction. Dn,f,ij, Ln,f,ij, Lne0,f,ij and Dv,ij,n depend on the actual dimensions of the elements.