What is an electromagnetic field?
- 10/11/2019
- EMF & Health, Environmental health
The electromagnetic field is a wave that results from two phenomena: the electric field “E” that occurs when I plug any electrical appliance into a power source (even when it’s switched off). It is linked to voltage and is expressed in Volt per meter. And the magnetic field “B” that occurs when the device is switched on. It is linked to the electric power and is expressed in Amperes per metre.
An electromagnetic field that remains constant over time is called a “static field”. It is typical of magnet-based equipment such as MRI scanners used in the medical field.
For many sources, its value varies over time. This is referred to as a sine electromagnetic field, the length of which represents the period of time between two maxima.
The electromagnetic wave is also characterised by its frequency, which corresponds to the number of times the signal is repeated per second. The shorter the wave, the higher its frequency and the greater its energy. The frequency of the electromagnetic wave should not be confused with its speed, which is that of light (300 million metres per second).
The frequency range for non-ionising radiation is between 0 Hz and 100 GHz. Beyond that are the ranges of optical radiation (including visible light) and ionising radiation, which is much more dangerous to health.
Electromagnetic fields: what are the risks for my family?
There are more and more sources of radiation at home that expose people to electromagnetic fields. WiFi, cordless phones, mobile phones, Bluetooth, but also microwaves and all the electrical appliances that surround us. Is it dangerous for your health?
These “non-ionising” high-frequency electromagnetic fields. Unlike other types of radiation, they are not energetic enough to affect the human body permanently. Certain sensory, stimuli or thermal effects are possible above certain thresholds.
