© FANTECH
2016
Attenuator
Flanking transmission
Figure 4.12. - Flanking transmission
Attenuator
If an attenuator is installed as shown, noise from the fan can
bypass the attenuator and enter the conditioned space. This is
known as flanking transmission and will negatively impact on
the expected attenuator performance.
Installing the attenuator through or against the wall minimises
the chance of flanking transmission via the duct system
ensuring the expected performance is achieved.
4.0 NOISE CONTROL (Cont.)
Figure 4.11. - Fan position relative to noise sensitive areas
INSTALLATION DO’S AND DON’TS
INSTALLATION DO’S AND DON’TS
P-16
P
Overlap wrap by
100mm at all joins
Best
Storeroom
Better
Do not place fans in ceiling spaces directly above noise
sensitive areas.
Better: Do place fans in ceiling spaces away from noise
sensitive areas.
Best: If fan cannot be relocated, wrap fan and surrounding
ductwork with a noise barrier material (When wrapping fans pay
particular attention to ensuring there are no holes at the joins).
Allow sufficient overlap in the wrap to ensure adequate coverage.
Remember that flexible connections will be the weakest link.