The airborne sound insulation index that must be provided by horizontal (floors) and vertical (walls) compartmentation elements is called D _nw.

The percussion sound insulation index is designated byL _n,w and represents the sound insulation to impact sounds that must be provided by the horizontal compartmentation elements of buildings.   These parameters are determined in accordance with the methodologies laid out in the following EN ISO international standards:

NP EN ISO 20140-3. Acoustics. Sound insulation measurement of buildings and construction elements. Part 3 Laboratory measurement of sound insulation to airborne sounds from building elements.

EN ISO 140-4. Acoustics. Measurement of sound insulation in buildings and of building elements. Part 4 Field measurements of airborne sound insulation between rooms.

EN ISO 140-5. Acoustics. Measurement of sound insulation of façades and of façade elements. Part 5 Field measurements of airborne sound insulation between rooms.

EN ISO 717-1. Acoustics. Rating of sound insulation in buildings and of building elements. Part 1 Airborne sound insulation.

EN ISO 140-6. Acoustics. Measurement of sound insulation in buildings and of building elements. Part 6 Laboratory measurements of impact sound insulation of floors.

EN ISO 140-7. Acoustics. Measurement of sound insulation in buildings and of building elements. Part 7 Field measurements of impact sound insulation of floors.

EN ISO 717-2. Acoustics. Rating of sound insulation in buildings and of building elements. Part 1 Impact sound insulation.

EN ISO 140-8. Acoustics. Measurement of sound insulation in buildings and of building elements. Part 8 Laboratory measurements of the reduction of transmitted impact noise by floor coverings on a heavyweight standard floor.

NP EN ISO 140-9. Acoustics. Sound insulation measurement of buildings and construction elements. Part 9 Laboratory measurement of airborne sound insulation from air gap ceilings common to adjacent rooms.

NP EN ISO 140-10. Acoustics. Sound insulation measurement of buildings and construction elements. Part 10 Laboratory measurement of sound insulation to airborne sounds from small building elements.