PTB has investigated the limits of human hearing (infrasound
and ultrasound) within the scope of an international cooperation project
(July 10, 2015) Are
wind farms harmful to humans? Some believe so, others refute this; this
controversial topic makes emotions run high. To give the debate more
objectivity, an international team of experts dealt with the fundamentals of
hearing in the lower limit range of the audible frequency range (i.e.
infrasound), but also in the upper limit range (i.e. ultrasound). The project,
which is part of the European Metrology Research Programme (EMRP), was
coordinated by the Physikalisch-Technische Bundesanstalt (PTB). At PTB, not
only acoustics experts, but also experts from the fields of biomagnetism (MEG)
and functional magnetic resonance imaging (fMRI) were involved in the research
activities. They have found out that humans can hear sounds lower than had
previously been assumed. And the mechanisms of sound perception are much more
complex than previously thought. Another vast field of research opens up here
in which psychology also has to be taken into account. And there is definitely
a need for further research.
If there is a plan to erect a wind turbine in front of
someone's property, many an eager supporter of the "energy
transition" quickly turns into a wind energy opponent. Fear soon starts
spreading: the infrasound generated by the rotor blades and by the wind flow
might make someone ill. Many people living in the vicinity of such wind farms
do indeed experience sleep disturbances, a decline in performance, and other
negative effects. Infrasound designates very low sounds, below the limit of
hearing, which is around 16 hertz. The wind energy sector and the authorities
often try to appease the situation, declaring that the sounds generated are
inaudible and much too weak to be the source of health problems.