The following is quoted from Dr. Alec Salt’s new paper on ILFN:
“Large wind turbines generate very low frequency sounds and infrasound (below 20 Hz) when the wind driving them is turbulent. The amount of infrasound depends on many factors, including the turbine manufacturer, wind speed, power output, local topography, and the presence of nearby turbines (increasing when the wake from one turbine enters the blades of another). The infrasound cannot be heard and is unrelated to the loudness of the sound that you hear. Infrasound can only be measured with a sound level meter capable of detecting it (and not using the A-weighted scale). Video cameras and other recording devices are not sensitive to infrasound and do not reproduce it.
“You cannot hear the infrasound at the levels generated by wind turbines, but your ears are indeed detecting and responding to it. The picture shows the enormous electrical potentials that infrasounds generate in the ear. The potentials (18.7 mV pk/pk amplitude in this case) are about 4 times the amplitude of any sounds that are heard. This shows the low frequency part of the ear is extremely sensitive to infrasound. Infrasound generates larger electrical responses than any other type of sound, including sounds you can hear presented at the loudest levels.”
Comment by Itasca Small on 09/26/2012 at 2:04 am
For the record. I would like to add my personal testimony to Dr. Salt’s paper. To those who are not aware, there are human beings who can perceive infrasound. It is an extremely unpleasant experience. Especially when the source is nearby. It feels like a long, low, harmonic wave oscillating through your body and creates an overwhelming pressure/pain perception in the ears and head. The instant reaction is to flee as quickly as possible to escape!
The most intense episode I have experienced occurred on the site of the Dry Lake Wind Power Plant in Navajo County, Arizona, USA. Oh, but, Iberdrola, Landowner Billy Elkins, and our county officials assure me that industrial wind turbines do not produce infrasonic wave radiation! Why, the Farmer John Pig Farm – well-stocked with breeding swine – is so certain the IWTs are harmless that they agreed to allow these 497-foot-tall monsters to be sited 500 feet from the pig pens and the humans caring for them. After all, what do we common folk know about science and technology, anyway?