This document specifies information additional to EN ISO 10140-1 necessary to carry out efficiently and under standardized conditions the determination of the sound reduction index of drywall systems of plasterboard with steel studs according to EN ISO 10140-2 "Acoustics - Laboratory measurement of sound insulation of building elements - Part 2: Measurement of airborne sound insulation". It specifies the additional requirements for the measurements of the sound insulation, the operating and fixing conditions to be used for the test as well as additional information to be given in the test report. Observe that all requirements in EN ISO 10140-2 shall still be fulfilled. The results obtained are used to convert frequency-dependent sound reduction index into single number ratings, according to EN ISO 717-1. These performances can be used to compare different products, or, and to express a requirement, or, and as input into estimation methods, such as EN 12354-1. The responsible committee is Working Committee NA 062-02-31 AA "Schalldämmung und Schallabsorption, Messung und Bewertung" ("Sound reduction and sound absorption; Measurement and evaluation") at DIN Standards Committee Materials Testing (NMP).