An Introduction to EMF and RF Frequencies.

I purchased a EMF/RF meter and planned to do the following class with a home education group.  As many now have children at home, I thought this may be useful for others.

The following is the idea for the class, which includes some discussion topics, show them how to use an EMF/RF meter to test their environment & phones, followed by a project to build a Faraday Cage for their home modem or phone.

EMF – Electromagnetic Frequency and RF – Radio Frequency.

At the low end of the electromagnetic spectrum are low-frequency (ELF) waves. These have longer wavelengths and come from the 50 to 60 Hz power lines that feed household sockets/appliances. These can pose health risks, especially when you are close to them for extended periods.

On the high end is radio frequency (RF) radiation. This comes from many electrical devices we use every day.  The higher the frequency, the greater the risk to health. For example, microwaves are very-high-frequency radiation, and they can pose a significant health risk. Many cell phone towers operate in the microwave range.

Broadcast towers, Radio technology, Cell phone towers, Cordless phones, Mobile phones, Computers, Televisions, Blue Tooth, WiFi, Transmitters, Receivers, Power lines, MRI’s, X-Rays, Smart Meters, 5G…

EMF Hz- measured in milliGauss (mG).

The Environmental Protection Agency recommends that you limit your exposure to 0.5 mG to 2.5 mG.  When you are three feet away from a microwave, you are exposed to up to 25 mG. 

There is no universally agreed upon safe levels of radiation. 

Today we’ll be testing the levels in this room, your mobiles and computers.  Testing done in ‘Microwatts Per Square Centimetre’ (u W/cm2), of which 0.002 would be a fairly safe environment and 0.008 would be a moderate level of harmful radiation.  0.205 and higher, means you’re being exposed to dangerously high levels of EMF.

You can also measure in ‘Millivolts Per Meter (mV/m),  40 mV/m said to be safe and 40-100 cause for concern.  Over 100 mV/m is dangerously high.

RF 10MHz to 300 GHz

Some effects on the body can include:

Loss of sleep/fatigue, lowered immune system, migraine/headaches, stress/anxiety, nausea, depression, loss of libido, eye irritation and cataracts, childhood leukaemia, neurological problems, physiological problems, nerve problems, epileptic fits, lethargy, cancers of all variety…

Things to Avoid:  Holding mobile or cordless phones to your ear.  Clothing with metal threads/fibres.

Advised:  Cell phones – Air Tube Headphones.  Cordless home phone or mobile phone on speaker.

Some Forms of Protection: 

Airtube Headphones, shielding materials (for clothing, hats, curtains, bed canopy, Faraday cages, Faraday paint, Himalayan salt lamps, Shungite – Stones, Jewellery, Stickers (for phones/electrical devices), plants especially the Peace Lily .


Michael Faraday FRS was a British scientist who contributed to the study of electromagnetism and electrochemistry.

Michael Faraday was born on 22 September 1791 in south London. His family was not well off and Faraday received only a basic formal education.

When he was 14, he was apprenticed to a local bookbinder and during the next seven years, educated himself by reading books on a wide range of scientific subjects. In 1812, Faraday attended lectures given by the chemist Humphry Davy at the Royal Institution and later worked there for him.

The RI now has a large section of its building dedicated to Michael Faraday, however it fails to show what many feels is his most important invention the ‘Faraday Cage’. 


The cage was an expansion on inventor Benjamin Franklin’s work that helped inspire many of the ideas behind the Faraday cage.

A Faraday cage or Faraday shield is an enclosure used to block electromagnetic fields. 

As a Faraday cage distributes that charge or radiation around the cage exterior, it cancels out electric charges or radiation within the cage interior. In short, a Faraday cage is a hollow conductor, in which the charge remains on the external surface of the cage.

This has been used in all sorts of applications, for example on airplanes.  Thanks to the aluminium hull of the plane, creating a Faraday cage, when the airplane is struck by lightning (which happens fairly often), the plane and its passengers aren’t affected.  The charge from lightning can pass harmlessly over the surface of the plane without damaging the equipment or people inside.

Materials for the Faraday Cage:

Aluminium Screen Mesh – Ebay or Modelling Art Supply Store. 

Wood – preferably cut to size to create a box frame.

Wood glue.

Metal L brackets

Saw – optional and not needed if wood is pre-cut.

Aluminium wire.

Hammer and nails.

Other ideas to show the class:

EMF/RF Meter, Mobile Phones, Himalayan Salt Lamp, Shungite (variety of), Torch (to show how to test if the shungite is real), airtube headphones, Copper Sheilding Material.