EMF FAQ

What does EMF stand for?

EMF stands for Electromagnetic Field. This is a broad term used to describe the spectrum fields generated by electric and magnetic energy. EMFs are classified on the electromagnetic spectrum according to their wavelength and frequency.

What are the different types of radiation?

The radiation coming from your cell phone is very different from that of ionising radiation. This radiation carries enough energy to knock electrons from atoms or molecules, thereby ionizing them. On the other side we have ‘non-ionising’ radiation which we experience everyday from our electronics. This is any type of electromagnetic radiation that does not carry enough energy per quantum to ionize atoms or molecules. However, this does not mean that non-ionising radiation is ‘safe’ because the human body is sensitive to all electromagnetic energy.

How do our electronics create electromagnetic fields?

As electric currents pass through circuits in our electronics, an invisible field of electric and magnetic energy emanates from the device, strongest at its source. If you place an EMF meter near these devices, you can ‘hear’ the sound of these fields. Until quite recently, our everyday electronic devices only emitted low frequency electrical and/or magnetic fields. However, the introduction of wireless technology such as WiFi has allowed the fields to extend much further from the device using radiofrequencies or microwaves.

What are the categories of EMFs that we experience everyday?

Electrical Fields (EFs) - typically measured in volts per meter (V/m) which represents the difference in electric potential between two points. Differences in voltage: the higher the voltage and the stronger the resultant field will be. EFs radiate from unshielded electrical wiring and devices such as laptops, screens and exist even when a device is switched off (but plugged in to the mains).

Magnetic Fields (MFs) - created when electric current flows: the greater the current, the stronger the magnetic field.  Magnetic field strength is typically measured on EMF meters as units of gauss which is a measurement of magnetic flux density. Strong MFs typically come from power lines, improper home wiring and appliances.

Radio Frequencies (RFs) - created when EMFs approach higher frequencies from wireless technologies like WiFi, GSM and Blueooth. RFs are typically measured in Watts (W) or Volts.

What is dirty electricity?

Dirty Electricity (DE) is created by erratic spikes and surges of electrical energy travelling along power lines and building wiring where only standard 50/60-Hertz AC electricity should be. It is an extension of EFs and MFs in that it sits in the low frequency EMF range. DE, also known as electrical noise, may occur in your household where wiring has been placed incorrectly or from dimmer switches which send high frequencies back into the circuit. You can check for DE using an EMI meter or better yet, get a building biologist to check your home.

Can I measure mobile phone masts and other wireless signals with a low frequency meter?

No, low frequency or extremely low frequency (ELF) meters only detect AC electric and magnetic fields which typically extend 6 - 8 feet from the source.

Can I measure the fields from powerlines and appliances etc with a RF meter?

No, RF meters can only detect high frequencies from wireless technologies, typically in the range of 700 MHz upwards.

Can an EMF meter measure the frequency of EMFs?

This is a common misconception with EMF meters. Most EMF meters are 'broadband' in that they measure the total EMFs across a (specified) broad band of frequencies and provide you with readings in things like V/m, mW or mG etc depending on the type of EMF and country of origin. The usual instrument for measuring both frequency and strength of EMFs is the spectrum analyzer. This instrument measures across a broad band of frequencies a little at a time, storing and/or displaying results for each individual narrow band of frequencies. Spectrum analyzers (SA’s) are very expensive but some simple, inexpensive SA's can measure a limited band of frequencies such as audio (music) or WiFi.

Why does my meter give different results to someone else's?

In the digital age and at microwave frequencies, there are many digital signals of many different types and it is much harder to decide on a definitive method of measurement. Meter Manufactures may calculate this differently and their meters may have different frequency ranges and different types of sensors. They may also be 'frequency weighted' and give different results at different frequencies. Therefore two different meters RF meters for example, are unlikely to give the same reading.