When predicting flanking transmissions in buildings, the sound reduction index of the involved elements is an input and should relate to resonant transmission only. If laboratory measurement results are used as input data, a correction must be applied (particularly for lightweight elements), which can be estimated from both the radiation efficiency of the element for airborne excitation and the radiation efficiency for structural excitation. These two quantities would be difficult to estimate by calculation, particularly for lightweight (often stiffened and multilayered) elements, and must therefore be measured. There is so far no standard for measuring radiation efficiency in laboratory.
Registration number (WIID)
41332
Scope
When predicting flanking transmissions in buildings, the sound reduction index of the involved elements is an input and should relate to resonant transmission only. If laboratory measurement results are used as input data, a correction must be applied (particularly for lightweight elements), which can be estimated from both the radiation efficiency of the element for airborne excitation and the radiation efficiency for structural excitation. These two quantities would be difficult to estimate by calculation, particularly for lightweight (often stiffened and multilayered) elements, and must therefore be measured. There is so far no standard for measuring radiation efficiency in laboratory.
