What is EMF & RF ?
EMF & RF
Electromagnetic radiation (EMR) is energy in waves (like visible light), emitted from a source. It travels at the speed of light.
This energy is both electric and magnetic. The waves alternate rapidly, from positive to negative in electrical terms, and from North to South pole in magnetic terms.
Electricity and magnetism are very closely related in nature. For example, when an alternating magnetic wave penetrates a body (including yours!) an alternating electric current will flow inside that body.
Electromagnetic radiation from a source penetrates the surrounding area, creating an electromagnetic field (EMF). This EMF is strongest at the source, and weakens with increasing distance until it becomes too small to measure.
A strong EMF can be due to a powerful source of radiation far away, or a weak radiation source very close by.
That is why the EMF your body experiences from your cellphone (when you make a call) is much stronger than the EMF you experience from the cell phone tower.
(Although the cell phone is a weak radiation source, it is located very close to your person, whereas the much more powerful cell tower is located thousands of times further away).
When understanding Non-Ionising radiation lets examine the Chart of the Electromagnetic spectrum below. Fig 1
These are the range of all the electro magnetic energies in physics that we know of
They range from ELF ( Brain waves) All the way to Gamma Rays in outer space.
- Radio waves and micro waves are the main band used in radio and wireless communications.
- Infra-Red used in remote control and night vision goggles, radiators heaters etc…
- Visible Lights main source is from the Sun.
- UV light used for sterilization, suitable amounts will induce the body to produce vitamin D.
- X Rays and Gamma Rays have a super short wavelength and super high frequency.
Ionizing And Non-Ionizing Radiation
|Frequency||Type Of Radiation||Sources|
|0 Hz-300 kHz||Electrical fields of devices,|
sections of AM radio
|3 kHz-300 MHz||Radio frequencies (RF)||Sections of AM radio, FM|
nuclear magnetic resonance
|300 MHz-300 GHz||Microwave (MW)||Domestic microwave devices,|
radar and other
|300 GHz-780 nm||Infrared (IR)||Solar light, heat and laser|
|780 nm 400 nm||Visible light||Solar light, phototherapy, laser|
|400 nm-100 nm||Ultraviolet (UV)||Solar light, fluorescent tubes,|
They are all just different forms of the same stuff – raw energy riding on a wave.
They can all be harmful to a person’s health because they penetrate your body and interact with molecules in your cells.
It is understood that when you move beyond UV light the frequency causes biological effects which is classed as ionizing radiation. When you go to the dentist or break a bone your vital organs are covered when receiving an X-Ray.
Non-Ionizing radiation is classed below UV light and are classed as not having ionizing effects upon people.
There is alot of evidence that non-ionizing radiation causes free-radicals in living things, this will be explored later.
Low Frequency EMFs (ELF and VLF)
The ELF band includes the important power-line frequency ( 50 Hz Ireland) which contributes greatly to our electromagnetic pollution. Power-lines, house-wiring and electrical appliances all create this kind of EMF.
An electrical appliance may emit electromagnetic radiation at more than one frequency.
At these low frequencies it is still possible to separate the electrical and magnetic components of the EMF. (At higher frequencies it can’t be done).
When the appliance is switched on and a current flows through it, the appliance (and its supply wire) will generate a magnetic field as well as an electric field. (A magnetic field is always generated when an alternating electrical current flows).
For low frequency EMFs, the electric field is easily shielded, even by flimsy screening. But the magnetic field penetrates most materials, including brick or concrete walls. It has no trouble penetrating a human body.
Because of this penetration, the magnetic field is the more important component of low frequency EMF, so this is the component that is usually measured – in milligauss (mG).
Radio Frequency EMF
The radio frequency band includes AM and FM radio and TV (VHF) transmissions.
For radio frequency EMF, the magnetic field strength and the electric field strength are proportional to each other, so both are of equal penetration, therefore you cannot separate one from the other. Where there is a known magnetic field strength, the electric field can be calculated from this and visa versa.
It’s easier to measure the electric field, so the intensity is quantified in Volts per metre (V/m).
The microwave band includes radiation from cell phones, cell phone towers, other communications systems and microwave ovens.
As for Radio waves, the magnetic field strength is proportional to the electric field strength, so we measure the electric field strength in Volts per metre (V/m).
These are high energy waves which penetrate deep into the human body, just as the microwaves in your oven penetrate deep into your food.
Nuclear Radiation (also called Ionizing Radiation)
The radiation from the top end of the frequency range (high ultra-violet, x-rays and gamma rays) has so much energy that when it collides with an electron in a molecule, it can knock that electron right out of its orbit.
This upsets the electrical charge of the molecule, and creates a positively charged molecule instead, called an ion. So this kind of radiation is called ionizing.
Because of their electrical charge, ions are very reactive chemically, and they quickly connect with other molecules nearby, trying to steal an electron to replace the one they lost.
If this happens to a molecule inside your body, it’s called a “free radical”. Just think of it as a molecular terrorist.
As you can imagine, too many free radicals mess up your biology, especially if they damage molecules inside your cells’ DNA.
Nuclear radiation is the most dangerous kind of electromagnetic radiation (although they can all be dangerous). So it’s quite important to make sure that you are not exposed to more than your body can handle!
Radiation emitted during nuclear power station accidents, is ionizing radiation.
Electromagnetic waves may be modulated to encode a digital or analog signal. This is how radio and microwave frequencies can be used to transmit audio or video information.
Radio and TV transmissions, as well as cellphone communications, all use a modulated signal on top of a basic ‘carrier’ wave. This will be discussed further in the EMF and emotional dysfunction page.