The
World Health Organization is one of the bodies which recognizes the special
place of low frequency noise as an environmental problem. Its publication
on Community Noise (Berglund et al., 2000) makes a number of references
to low frequency noise, some of which are as follows:
• " It should be noted that low frequency noise, for example,
from
ventilation systems can disturb rest and sleep even at low sound levels"
• "For noise with a large proportion of low frequency sounds
a still lower
guideline (than 30dBA) is recommended"
• " When prominent low frequency components
are present, noise
measures based on A-weighting are inappropriate"
• "Since A-weighting underestimates
the sound pressure level of noise with
low frequency components, a better assessment of health effects would
be to use C-weighting"
• "It should be noted that a large proportion of low frequency
components
in a noise may increase considerably the adverse effects on health"
• "The evidence on low frequency noise is sufficiently strong
to warrant
immediate concern"
This present study considers some properties of low frequency sounds,
their perception, effects on people and the criteria which have been developed
for assessment of their effects. Proposals are made for further research,
to help to solve the continuing problems of low frequency environmental
noise.
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