Launch of new fact file on electromagnetic fields and health

Amongst its contents, the document examines the nature of EMFs and safe levels at different frequencies and provides links to websites with further information on this subject.

What are electromagnetic fields?

Electric and magnetic fields are produced wherever electricity is used. Electric fields are generated by voltages, magnetic fields are produced by currents.

In other words, electric fields exist around all wires and electrical devices whenever they are connected to a supply of electricity.

However, magnetic fields are only produced when current flows and hence power is being used. The higher the voltage or the greater the current, the stronger the field produced.

At higher frequencies, the electric and magnetic fields become coupled together in a particular relationship. They are then referred to as electromagnetic waves or radio waves.

Which frequencies are people exposed to?

The electromagnetic spectrum spans a vast range of frequencies. All frequencies lower than the ultraviolet are referred to as “non-ionising” because they do not have sufficient energy to break chemical bonds.

Concerns about EMFs and health have focused largely on two quite separate non-ionising frequency bands. One is 50 or 60 Hz, the frequency of electric power systems.

The other is in the hundreds of MHz to the GHz range, where mobile phones and other wireless devices operate.

For simplicity, this fact file considers these two ranges of frequencies separately.