A descriptive cross- sectional study of annoyance from low frequency
noise installations in an urban environment
Noise & Health, (2003)Abstract
In order to improve the living conditions for respondents highly exposed
to traffic noise, it has been recommended that one side of the building
should face a "quiet side". Quiet may, however, be spoilt by noise
from installations such as ventilation and air-conditioning systems.
The noises generated by installations of this kind often have a dominant
portion of low frequencies (20-200 Hz) and may be a source of great
annoyance and sleep disturbance. This paper describes the cross-sectional
part of an intended intervention study among residents exposed to
traffic noise on one side of the building and to low frequency noise
from installations on the other side of the building. A questionnaire
masked as a general living environment study was delivered to a randomly
selected person in each household. In total 41 respondents answered
the questionnaire (71% response rate). Noise from installations was
measured indoors in a bedroom facing the courtyard in a selection
of apartments and outdoors in the yard. 24h traffic noise outdoor
and indoor levels were calculated. The noise levels from installations
were slightly above or at the Swedish recommendations for low frequency
noise indoors with the window closed and exceeded the recommendations
by about 10 dB SPL when the window was slightly opened. The proportion
of persons who reported that they were very or extremely annoyed
indoors from noise from installations was more than twice as high
as for traffic noise. Installation noise also affected respondents'
willingness to have their windows open and to sleep with an open
window. The high disturbance of installation noises found in this
study indicates the importance of also regulating the noise exposure
on the "quiet side" of buildings. Further studies will give a better
base for the extent of annoyance and acceptable levels of installation
noises.