electromagnetic fields
Electromagnetic fields are waves with an electric and a magnetic component. Waves are characterized by their frequency , concretely by the number of vibrations per second and wave height, the amplitude . Electromagnetic fields propagate as light and X-rays with the speed of light.
- Overhead electrical power lines with AC
- Overhead electrical power lines with direct current (HVDC)
- mobile
- Biological effect on humans
The electromagnetic fields are divided into
Non-ionizing radiation:
These include risks from the normal power supply low fields or radiated from the transmitting towers radiofrequency fields.Ionizing radiation:
This includes, for example, the X-rays or radioactive decay radiation.
For non-ionizing radiation energy ranges - even with such high field strength - not to break up the atoms or molecules, ie to ionize.
Overhead electrical power lines with AC
When operating from AC high voltage three-phase alternating lines (50 flows Hz ) through the cable. This current produces a magnetic field ( Faraday's law ). The high voltage (10 kV to 380 kV ) also causes an electric field.
The electric fields can be perceived, for example by vibration of the hair. Physiologically this is harmless. Whether there are long-term effects when people have exposed permanently these magnetic fields, was the subject of numerous epidemiological studies. Especially for leukemia in children showed some that there is a connection between the magnetic fields and an increased incidence is the disease. However, this purely mathematical context is not evidence of causality . Laboratory experiments have been able to show any mechanism of action, which could prove a plausible connection.
Overhead electrical power lines with direct current (HVDC)
In the current-transmitting high-voltage lines with direct current, the size of the maximum magnetic flux densities in the range of variation of the values of the earth's magnetic field as they occur regionally and in homes. They are therefore not relevant to health.
Mobile
In Central Europe, there are now more mobile phone contracts than residents. The mobile phone technology has evolved into a universal information, communication and entertainment platform.
The mobile extension is governed by uniform federal laws. Radio equipment shall thereafter the limits of the regulation on electromagnetic fields ( 26 Federal Immission Control Ordinance - BImSchV ) comply. The adequacy of the protective effect of the limits was the highest court checked and confirmed.
With the amendment of 26 BlmSchV in August 2013, the limits are in accordance with the EU directive and the recommendations International Commission for Non-Ionising Radiation Protection (ICNIRP) in the entire frequency range from 0 Hertz expanded to 300 gigahertz.
Biological effect on humans
The high-frequency fields in the tissue water molecules in the vibrational shift. This creates frictional heat. If the limits adhere to, this warming, if it occurs at all, much lower than that which takes place through its own movement in the body.The Ministry of Health has encouraged the development of a personal dosimeter. This could be measured, which radio frequency fields is exposed to over 24 hours in the life a person, starting from all transmission sources including own phone calls. In the pilot study, no correlation between the measured values and being returned on the day of examination.
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