Abstract / scope
Specifies a method for measuring a quantity called the suspended ceiling normalized level difference when the sound transmitted by paths other than the required paths is negligible.
ISO 140-9:1985Withdrawn
Acoustics — Measurements of sound insulation in buildings and of building elements — Part 9: Laboratory measurement of room-to-room airborne sound insulation of a suspended ceiling with a plenum above it
Acoustique — Mesurage de l'isolation acoustique des immeubles et des éléments de construction — Partie 9: Mesurage en laboratoire de l'isolation au bruit aérien de pièce à pièce par un plafond suspendu surmonté d'un vide d'air