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Wavin AS+
Technical Manual
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for the specific environment. An adverse effect of noise refers
to any temporary or long-term impairment of physical, psy-
chological or social functioning that is associated with noise
exposure. Specific noise limits have been set for each health
effect, using the lowest noise level that produces an adverse
health effect (i.e. the critical health effect).
It is not enough to characterize the noise environment in terms
of noise measures or indices based only on energy sum-
mation (e.g., LAeq), because different critical health effects
require different descriptions.
It is equally important to display the maximum values of the
noise fluctuations, preferably combined with a measure of the
number of noise events. A separate characterization of night-
time noise exposures is also necessary.
For indoor environments, reverberation time is also an impor-
tant factor for things such as speech intelligibility. If the noise
includes a large proportion of low-frequency components, still
lower guideline values should be applied.
Supplementary to the guideline values given in Table 2, pre-
cautions should be taken for vulnerable groups and for noise
of certain character (e.g. low-frequency components, low
background noise).
3.5.1. Sources of noise in buildings
The noise generated by the building and its utilities may be
classified as follows:
Noise due to filling operations
Noise generated by control equipment
Intake noise
Discharge noise
Noise due to impact or shock
Noise is generated by moving parts or by flowing media.
Waste water discharge pipes are prone to vibration, particu-
larly where water flows through downpipes, or is forced to
change direction in joints and elbows (noise due to impact
or shock). Experience shows that the greatest problems
are typically caused by the transmission of structural noise,
particularly in the area of pipe clamps and brackets or where
pipe-work is run through walls or ceilings.
The noise created from waste systems obviously depends
greatly on the vertical piping. Here the falling water clashes
against the wall of the pipes and fittings. The generated noise
is transmitted directly to the pipes and indirectly through the
ducts and installation walls. Therefore, the thickness and
mass of the solid materials are of great importance, just like
the fixing brackets and other elements which connect pipes
to their supports.
3.5.2. How noise is measured
If we consider the “installation chamber” to be the room in
which the pipes are installed (generally the bathroom), the
room next door divided by the installation wall is called the
“protected chamber”. The noises emitted are measured in the
protected chamber according to EN 14366.
Fig. 5: Example of noise propagation during drainage.
Bathroom
Installation
chamber
Protected
chamber
Bedroom
<= 30 dB (A)
points of noise
propagation
<= 35 dB (A)
