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Electromagnetic fields

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Elektromagnetische Felder

Electromagnetic fields

Through the use of certain technologies – e.g. power supply network and mobile communication – electric, magnetic and electromagnetic fields are generated in man´s environment. These fields can be described by

  • their strength (amplitude),
  • their oscillation (wave length) and
  • number of oscillations (frequency).

One differentiates high-frequency and low-frequency fields, they are part – as is optical radiation – of non-ionising radiation. In contrast to ionising radiation – e. g. X-rays – the energy of this radiation is not sufficient for charging atoms and molecules electrically – for ionising them. Nevertheless can this type of irradiation have impacts on health. Different concepts serve to protect against immediate hazards and as precaution.


Electric and magnetic fields describe the spatial distribution of a force which can act upon electric charges and currents. Electromagnetic fields can be generated artificially, but also occur naturally in the environment. They belong to "non-ionising radiation". Electromagnetic fields are part of the electromagnetic spectrum. Over its entire range, the spectrum extends from static electric and magnetic fields over optical radiation to very energetic gamma radiation.

Stromtrasse auf einem Feld

What are high-voltage lines?

The electricity supply at home has a voltage of 230 volts (230 V). However, much higher voltages are used to deliver electricity to homes. Overhead lines carry up to 380.000 volts (380 kV) to transport electricity from power stations to towns and urban centres.

A woman, using a tablet.

Smartphones and tablets

Just like classic mobile phones, smartphones use the same high frequency electromagnetic fields to transmit speech and data. Besides mobile communication connections, Smartphones can usually also make use of Wireless Lan (wi-fi). This is similarly the case for tablets: They use high frequency fields for wi-fi connections and often also have mobile communications inbuilt.

The BfS gives tips to reduce individual radiation exposure.

What are high-frequency electromagnetic fields?

Electric and magnetic fields in the frequency range between 100 kilohertz and 300 gigahertz are referred to as high-frequency fields. As electric and magnetic fields are closely coupled at high frequencies, they are also called "electromagnetic" fields.

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