Biology Reference
In-Depth Information
Ldn = 70
65
Ldn = 70
60
65
60
55
55
50
50
20
40
60
80
100
20
40
60
80
100
0
0
Age
Age
Fig. 5.2
Predicted percentage of highly annoyed persons (%HA) in relationship to noise level
[Ldn in dB(A)] of international pooled data set (
left image
) and the Amsterdam Airport Schiphol
data set (
right image
).
Ldn
average equivalent noise level during daytime (
d
) and nighttime (
n
)
(Reproduced with permission from Van Gerven et al.
2009
)
dwelling, length of residence, receipt of benefits from the noise source). The
annoyance is related to amount of isolation from sound at home and to five attitudes
(fear of danger from noise source, noise prevention beliefs, general noise sensitiv-
ity, beliefs about the importance of the noise source, and annoyance with non-noise
impact of the noise source).
It is quite clear that annoyance assessment based on decibel measurement is not
sufficient to evaluate the quality of the sonic urban ambience. The soundscape
concept seems a more integrated and efficient way to assess such quality.
Annoyance is a quite contentious argument because a noise for a people can be a
kind of lifestyle for others. The perception of a sound is a complex process in which
sound source is identified, the direction and distance evaluated, the recall to a
memorized similar or dissimilar sound, and contemporarily the situation during
which that sound was heard at that time. Sound memory produces the evocation of
feelings and visual scenes. In the analysis of sonic annoyance it is necessary to
separate analytically the structure of the sound from personal subjective characteri-
zation (e.g., loudness, unpleasantness) as suggested by Schulte-Fortkamp and
Nitsch (
1999
). Finally, different groups of people (residents, visitors, workers,
etc.) may have a different judgment of a specific sound.
Annoyance is the result of long exposure to unwanted sounds and can be rated
using questionnaires graded as “none/a little/rather much/very much.”
The level of annoyance expressed by a subject reflects their personality and
noise sensitivity. Defeat reaction, increase of blood pressure, and disturbance of
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