Fluorescent light, dimmers and other electronic equipment connected into our circuits create voltage frequency fluctuations, which are often called 'dirty power', or 'dirty electricity'.
There is mounting evidence that the messy noise they create can interfere with our health, causing sleeping problems, fatigue, allergies, and cancer.
See the brilliant summary by Mikko Ahonen.
Building Biologists have always believed that electric and magnetic fields and electro-magnetic radiation are a health hazard.
Over recent years, it has been discovered that it is not just the quantity, but also the quality of the power that can cause health problems.
Originally, it was found that electronics companies, or companies that used electronic equipment in their production processes, had problems with unexplainable break-downs.
The cause was found to be electronic equipment that 'polluted' the power network.
Such equipment might be dimmers, motors, power supplies, energy-saving lightbulbs, and many other commonly used devices.
There now is a range of filters, we are currently selling a filter that goes into the fuse box, but there are others that can be plugged into the power points.
Clean, filtered pattern on the oscilloscope:
Mikko Ahonen (University of Tampere) produced an informative slide show on this topic.