Infrasound and inaudible LFN
Industrial wind turbines also produce infrasound
and/or inaudible LFN. There is debate about the
impact from these low frequencies of noise. It has
been suggested that these low frequencies are not
sufficient to result in negative effects. However,
Farboud and colleagues state that “... there is an
increasing body of evidence suggesting that infrasound
and low frequency noise have physiological
effects on the ear.” Salt and Kaltenbach58 report,
“based on well-documented knowledge of the
physiology of the ear and its connections to the
brain, it is scientifically possible that infrasound from
wind turbines could affect people living nearby.”
In a 1990 NASA technical paper, Hubbard and
Shepphard59 report that
[p]eople who are exposed to wind turbine noise inside buildings
experience a much different acoustic environment than do
those outside. ... They may actually be more disturbed by the
noise inside their homes than they would be outside. ... One of
the common ways that a person might sense the noise-induced
excitation of a house is through structural vibrations. This
mode of observation is particularly significant at low frequencies,
below the threshold of normal hearing.
Low- frequency noise produced by some IWT projects
in Ontario has been found to be inaudible outside
the home but audible inside and “... quite
annoying to the occupants.”
Low- frequency noise from IWTs has resulted in
reported annoyance, sleep deprivation and uninhabitable
living conditions. To escape the noise, some
Ontarians report sleeping in vehicles, tents, trailers,
basements lined with mattresses, garages, and at the
homes of relatives or friends. Ontario does not have
“... measurement procedures or criteria for addressing
indoor noise intrusions due to wind turbines ....”