EMF and their effects on the human organism
Advancing technology is leading to an increase in the use of devices with radio frequencies such as Bluetooth and WLAN. But what effects do electromagnetic fields (EMFs) have on the human body?
In this blog post, we take a look at the need for EMF measurements, applicable standards and guidelines and the various effects on humans.
DESCRIPTION OF ELECTROMAGNETIC FIELDS
Electromagnetic fields are omnipresent and surround electrically powered devices or are deliberately used for wireless communication. They are caused by changes in electrical currents and voltages.
Both alternating current and direct current are surrounded by electromagnetic fields and generate electromagnetic fields themselves. The spectrum of these fields ranges from long waves in the low frequency range to short waves in the high frequency range. The frequency ranges and the corresponding examples are visualized in the following diagram.
EMF measurements and standards
Electronic devices generate electromagnetic fields (EMF) at different frequencies. All devices that generate radio frequencies must comply with certain limit values, not only from a technological point of view, but also from an occupational health and safety perspective. Electromagnetic fields can have an effect on the human organism, depending on the frequency and strength.
To protect people and animals, there are German and EU-wide laws that prescribe limit values and measures for electromagnetic fields.
To protect employees, employers are obliged to carry out EMF measurements at workplaces and to document compliance with the prescribed limit values.
The following table is an excerpt from the national and international standards and guidelines for protection against EMF:
| Standard/guidelines | Description |
| 2013/35/EU | Protection of employees from hazards due to exposure to electromagnetic fields. |
| BGV B11 | Regulation on how to proceed if employees are exposed to electromagnetic fields. |
| 26 BlmSchV | Definition of personal protection limits for radio equipment |
| ICNIRP`10 Occupational/Public | International limit value recommendations for radio equipment |
| EMFV | Ordinance on the protection of employees from hazards due to electromagnetic fields. |
| IEEE C95 Restricted/Unrestricted | Standard of measurement methods for the protection of persons from EMF |
We use our modern equipment to carry out measurements in accordance with EMF guidelines. The measurements can be carried out in our laboratory or on your premises at the relevant workplaces or machine environments.
Effects of EMF on the human organism
Electromagnetic fields (EMF) are omnipresent and influence the human organism in various ways. The diversity of electromagnetic fields is reflected in equally diverse effects. So far, mainly short-term effects have been scientifically proven. However, there are assumptions about potential long-term effects that have not yet been scientifically proven and are therefore not discussed in detail in this text.
DIFFERENCE BETWEEN DIRECT AND INDIRECT EFFECTS
Direct effects are physiological in nature and show a direct influence of radio frequencies on the human organism. These effects include the heating of cell tissue and the disruption of the sensory organs, which can lead to visual or auditory impairment.
Indirect effects refer to events that are triggered by electromagnetic fields and are not directly biological in nature, but can potentially endanger health or life. Electromagnetic fields can impair the function of implants. This applies in particular to active implants such as pacemakers or neurostimulators.
EMF SIGNALFORM
DISTINCTION BETWEEN ELECTRIC, MAGNETIC OR ELECTROMAGNETIC FIELDS
In low frequency ranges, there is a clear separation between electric and magnetic fields. Electric fields arise when an electrical voltage is present in a device. Magnetic fields are generated when electric charges, i.e. a flowing current, move.
In high frequency ranges, we speak of electromagnetic fields. The signal forms of the waves are considered together here, as they propagate in space decoupled from the source and it is not possible to differentiate between them.
STATIC ELECTRIC FIELDS
Static electric fields are created by a redistribution of electric charge carriers in a material or between materials. This process is known as influence. In static electric fields, the charge distribution remains stable as it is not a changing electric current.
Here are some characteristics and effects of static electric fields:
- Penetration depth into the body: Static electric fields hardly penetrate the body. The inside of the body remains largely field-free.
- Distortion of the electric field on the body surface: Higher field strengths can occur than in an undisturbed field.
- Surface effects: Are limited to the body surface. On the one hand, they are visible through the erection of hair or through the electrostatic discharge of a body.
STATIC MAGNETIC FIELDS
Static magnetic fields exert forces on electrically charged particles in the body, especially when these particles are in motion. Here are some of the effects and potential risks of static magnetic fields:
- Effect on blood flow: Strong magnetic fields can slightly slow down the blood flow in large arteries.
- Fast movements in a static magnetic field can cause sensations such as dizziness, nausea and a metallic taste.
- Attraction of ferromagnetic objects: This poses a potential projectile risk if metallic objects are in the vicinity and are attracted by the magnetic field.
- Force effect on passive implants: This can lead to changes or stress on the implants. Especially if the implants contain ferromagnetic components.
- Functional disorders with active implants: With active implants, such as pacemakers, induced body currents can lead to malfunctions due to the movement of a person in a static magnetic field.
It is important to note that the aforementioned effects usually occur with very strong magnetic fields, such as those used in magnetic resonance imaging (MRI). In everyday situations, such intense magnetic fields are not normally present.
LOW-FREQUENCY ELECTRIC AND MAGNETIC FIELDS
In the human body, as in all other living organisms, internal electric fields and currents occur naturally:
- Electrically charged particles are moved during the metabolic processes.
- Signals between nerves and synapses are transmitted by electrical impulses.
- The heart is electrically active.
Low-frequency electric fields are caused, for example, by alternating current with a frequency of 50 Hz.
Low-frequency electrical and magnetic waves penetrate the human body and can generate additional currents there. According to current knowledge, weak fields have no effect on the human organism. However, as soon as the field strength exceeds certain limits, the body can be damaged.
This process, in which the human body is charged in an alternating current field and currents are passed through it, is characteristic of low-frequency electric fields. The effects are generally limited to the surface of the body and various effects can occur, including hair vibrations or a tingling sensation on the skin.
Proven effects include irritation of sensory organs, nerves and muscles as well as dysfunction of the heart and active implants (e.g. pacemakers).
In addition, the function of passive implants, such as artificial joints, can be influenced by the compression of body currents at the metallic elements.
HIGH-FREQUENCY ELECTRIC FIELDS
In contrast to low-frequency fields, high-frequency electromagnetic fields do not penetrate the human body, or only a few centimeters.
The high-frequency waves cause the ions and polar molecules to oscillate in time. This creates frictional heat. This effect is specifically used in the microwave to heat food.
If this heat is generated in the human body, it can be harmful to health. Proven effects of strong high-frequency fields are the disruption of the metabolism and the heating of active and passive implants.
LIMIT VALUES FOR THE EFFECT ON THE HUMAN ORGANISM
The current strength in relation to the area through which the current flows is described as current density (J) and measured in amperes per square meter (A/m2).
Die Stromdichte (J) ist im Verhältnis zur körperinternen elektrischen Feldstärke (Ei) entscheidend für die biologische Reaktionen im Körper. Je weiter die Stromdichte (J) die körperinterne elektrische Feldstärke (Ei) überschreitet, desto größer sind die gesundheitlichen Risiken.
Examples of current densities and effects on the human organism:
| Current density J | Effect on the human organism |
| 1 – 10 mA/m2 | No influence |
| 10 – 100 mA/m2 | Influencing the central nervous system, visual sensory impressions |
| 100 – 1000 mA/m2 | Health impairment due to the stimulation of nerve and muscle cells |
| > 1000 mA/m2 | Cardiac dysfunction possible: cardiac arrhythmia & ventricular fibrillation |
CONTACT
Josip Horvat
Bereichsleiter EMV-Labor
Telefon: +49 (7172) 926 13-33
E-Mail: josip.horvat@baudisch.de
Carsten Hampel
EMV-Experte
Telefon: +49 (7172) 926 13-34
E-Mail: carsten.hampel@baudisch.de
Baudisch Electronic GmbH
Im Gewerbegebiet 19
73116 Wäschenbeuren