An EMF is an ElectroMagnetic Field.
Electromagnetic waves have both electric and magnetic fields, perpendicular to each other, that travel through space in an invisible wave-like pattern at the speed of light.
Electric fields are created by differences in voltage whenever a positive or negative electrical charge is present. The higher the voltage, the stronger will be the resultant field.
- Electric fields arise from voltage.
- Their strength is measured in Volts per metre (V/m).
- An electric field can be present even when a device is switched off.
- Field strength decreases with distance from the source.
- Most materials shield electric fields to some extent.
Magnetic fields are created when electric current flows: the greater the current, the stronger the magnetic field.
- Magnetic fields arise from the motion of electric charges.
- Their strength is measured in amperes per meter (A/m). Commonly, EMF investigators use a related measure, flux density (in microtesla (µT) or millitesla (mT) instead.
- Magnetic fields exist as soon as a device is switched on and current flows.
- Field strength decreases with distance from the source.
- Magnetic fields are not attenuated by most materials.
A changing magnetic field will induce a changing electric field, and vice-versa - the two are inextricably linked. Fluctuations in these fields form electromagnetic waves.
Electromagnetic waves can travel not only through air and solid materials, but also through space.
Electromagnetic fields are present everywhere in our environment but are invisible to the human eye.
The Earth itself has its own magnetic fields. Earth’s magnetic fields are comprised of a variety of sources, including the overall direct current (DC) field of the planet, magnetized rocks under our feet, Schumann resonances, solar flares, tectonic plate movements, telluric currents on the planet’s surface, and cosmic radiation.
image source https://newearth.media/tag/emf/
The human body produces complex electrical activity in all cells, including neurons, endocrine, and muscle cells. As with all electricity, this activity also creates a magnetic field.These fields are extremely weak and are only detectable with extremely sensitive equipment, and requires blocking out all other external magnetic fields, including the Earth’s magnetic fields.
image source https://au.pinterest.com/explore/electromagnetic-field/
Electronic devices also produce EMFs (as well as radiofrequency energy or RFs, which we will cover in an upcoming post), which can have a significant impact on the human body in our increasingly technologically driven world.
All forms of electromagnetic energy are collectively known as the electromagnetic spectrum.
Image Source: http://www.public.navy.mil/navsafecen/Pages/acquisition/radio_frequency-radiation.aspx
Different forms of electromagnetic energy are categorized by and expressed in terms of their frequencies, wavelengths, and total energy. The strength of an EMF depends on its wavelength and frequency: more waves with shorter wavelengths create more energy as you move up the spectrum.
Now that you know what are EMFs and how they work, why do they matter?
More energy (measured in electron volts) poses more threat to human health. In fact, "the Environmental Protection Agency (EPA) has labeled magnetic fields a class 3 carcinogen." source
Electric fields can affect the electrical communication in your body, such as your brainwaves, or the ability of your neurons to fire and communicate. It can also impede inter-cell communication anywhere in your body. Health problems that can manifest as a result to this type of exposure include neurological- and behavioral changes, altered cell growth, cell mutations, fibromyalgia, chronic fatigue, and even cancer. ~ source