Infrasound & Human Health

We would refer to the ongoing work of Prof Mariana Alves Pereira, probably the world’s leading authority on Vibro Acoustic Disease:

Her advice:

“Flee! If children are involved, Flee Faster”

The following extract clearly shows the amount of Infrasound generated by wind farms far exceeds that in the audible spectrum (the darker segment).

Here is a video of Mariana’s presentation in Slovenia and well worth watching.

If you prefer to read, then perhaps the most concise presentation on the subject is by Peter R Mitchell AM, BChe in a paper published in March 2016:

Infrasound is common; but most natural infrasound is irregular and random, or is caused by a transient event. Some frequency bands below 20 Hz have been shown experimentally to cause a physiological stress response in humans at below audible levels.[3] Industrial machinery noises are often emitted day and night and with significant energy in the ILFN spectrum as is the case with wind project sound emissions.

Infrasonic pulsations, (Amplitude Modulation), travel much larger distances than audible noise and easily penetrate normal building materials, and once inside can resonate building elements (i.e., increase in impact), inside rooms.[4]

Infrasonic pulsations from a single 4 MW wind turbine were measured 10km from their source by NASA researcher William Willshire in 1985.[5] Recent data collected by acoustician Les Huson in Australia and the United Kingdom at onshore and offshore wind developments, has shown that attenuation of infrasound can be much less than the 3dB per doubling of distance quoted by Willshire in 1985.[6]

Some acoustic pressure pulsations are relatively harmless and indeed even pleasant to the body, including waves on a beach. Organ music at frequencies just below 20 Hz generates ‘feelings” in people that can be either pleasant or unpleasant, and have been designed to produce emotive effects.[7] Once it is understood that different frequencies can have very different effects on humans it is easy to understand the importance of accurate acoustic prediction and post start-up measurement across the full frequency spectrum.

Dr Neil Kelley and his colleagues from NASA demonstrated in the 1980’s that wind turbine generated energy pulses and noise in the infrasonic and low frequency bands, which then penetrated and resonated inside the residents’ living structures, directly caused the range of symptoms described as “annoyance” by acousticians and some researchers.[8] Annoyance is a non-quantitative word that implies mildness. A more accurate general descriptor would be mild, serious or intolerable “impacts”.

Residents and their treating medical practitioners know these symptoms and sensations include repetitive sleep disturbance, feelings of intense anxiety, nausea, vertigo, headaches, and other distressing symptoms including body vibration. American Paediatrician, Dr Nina Pierpont, gave this constellation of symptoms the name “wind turbine syndrome” in 2009.