Mobile Communications and Health

Men passing by an office building.

How mobile telephony works

Today, people take it for granted that they can make phone calls or transmit data wherever they are and whenever they want. What is the technology behind this?

What impact do electromagnetic fields have

Mobile communications uses electromagnetic fields to transmit information. But what impact do electromagnetic fields have on human beings?

What is being researched today

Is research being carried out into mobile communications and health? What issues are addressed in the latest studies?

Strict compliance with the valid exposure limits ensures the safe use of mobile communications.

The limit values are based on comprehensive research findings. For more than 50 years, scientists – in Germany and at international level – have been analyzing the potential impact of electromagnetic fields on health. The expert committees of the World Health Organization and the International Commission on Non-Ionizing Radiation Protection (ICNIRP) set recommended limit values and regularly monitor them. To do so, they evaluate the latest research findings on an ongoing basis. In the opinion of these experts, mobile communications is safe and poses no threat to health, provided that the limit values are ensured.

This was again confirmed by the new ICNIPR Guidelines in 2020 and numerous national expert bodies in Germany, The Netherlands, UK, Northern European Countries and so forth.

ICNIRP Guidelines 2020

Yes. The limit of 2 watts per kilogram for cell and smart phones has been fixed in the EU Council's recommendation in 1999 and applies in Germany as well as in all other European countries.

Cell and smart phones must comply with the limit value even at maximum transmission power. The limit value guarantees that mobile devices can be used safely by all users.

All cell phones are designed not only to comply with the defined limit of 2 watts per kilogram but also to remain well below it (adaptive power control).

The limit is based on the recommendations of the International Commission on Non-Ionizing Radiation Protection (ICNIRP), a committee of experts recognized by the World Health Organization (WHO). ICNIRP reviews the validity of the limit values on an ongoing basis. It currently concludes that it is safe to use mobile communications provided that the limit values are ensured.

SAR stands for "specific absorption rate". SAR is expressed in units of watts per kilogram (body weight) (W/kg). The SAR value of a cell or smart phone indicates the maximum degree to which the head may absorb electromagnetic fields during a phone call with the device.

All manufacturers check to ensure that their cell and smart phones comply with the exposure limit and publish the maximum values measured as the "SAR value" in their operating guides.

You will find information about the SAR levels of Deutsche Telekom's cell and smart phones at:, in Telekom Shops and in the manufacturers' operating guides.

The European Committee for Electrotechnical Standardization (CENELEC) standardized the way the SAR level is measured in the year 2001. All manufacturers use this system to measure the SAR levels of their devices. 
Manufacturers check to ensure that their cell phones comply with the exposure limit of two watts per kilogram (body weight) (2W/kg) and publish the maximum SAR values measured in their operating guides. The provisions governing the SAR measurement system are described in international standard IEC/EN 62209.

The measuring system consists of a plastic object shaped like a head. It contains a special fluid, which has properties that cause electromagnetic fields to propagate in it in the same way as in human head tissue. The cell or smart phone which is being tested and which is transmitting at full power is held to the 'ear' on the plastic head. A measuring probe records the distribution of SAR in the liquid inside the head and calculates the maximum SAR level.

The SAR values published by Deutsche Telekom correspond with the maximum levels stipulated by the EU standard.

SAR values (German)

All SAR levels below the limit guarantee that it is safe to use the cell phone. All mobile devices sold by Telekom comply with the defined exposure limits.

Differing SAR values do not mean differences in safety, provided they lie below the exposure limit. According to the International Commission of Non-Ionizing Radiation Protection (ICNIRP), this applies to all user groups, i.e., includes particularly sensitive people.
However, some people feel better with a lower SAR level and use the SAR value as a selection criteria when buying a new cell or smart phone. All manufacturers therefore quote the SAR levels in the operating guides for their devices.
You will find information about the SAR levels of Deutsche Telekom's cell and smart phones at:, in T-Shops and in the manufacturers' operating guides.

In all our national companies, the safety of mobile sites has to be confirmed by compliance declarations. The safety assessment is regularly performed by calculations or measurements for all mobile sites with more than 10 Watt transmitting power in order to show compliance to the nationally applied exposure limits.

In Germany, the Federal Network Agency (for electricity, gas, telecommunications, posts and railways, ( checks that the limit values for mobile communications are complied with.

Inspection takes place on the basis of the technical data and construction documents prior to commissioning and each time a technical modification takes place on a mobile communications base station. If all requirements are fulfilled, the Federal Network Agency issues an operating license – the site certificate.

The site certificate defines the areas around every base station that must be kept clear for safety reasons. The safety clearances are derived from the exposure limits and ensure that people can reside permanently outside the safety area without any risks for their safety. As a general rule, the safety clearance around base stations for GSM, UMTS and LTE is several meters.

As well as issuing a site certificate, the Federal Network Agency checks at irregular intervals and without notice whether mobile communications facilities continue to fulfill the conditions for the operating license.

The mobile radio fields in publicly accessible areas and private homes are far below the limit values.

This is confirmed by measurements carried out since rollout of the LTE technology. All measurement programs come to the conclusion that: Readings at all measurement points were significantly lower than the valid exposure limits – even under extreme conditions (i.e., maximum load) and with additional loads from GSM, UMTS and LTE mobile communications facilities.

Measurements are also regularly performed in most of the European countries. As an example, the Pedion24 program in Greece is performed by scientific bodies and constantly reports on the nationwide exposure situation.

EMF monitoring by the Federal Network Agency

Yes. The effects of electromagnetic fields on human beings have been researched thoroughly over the last few decades. On the basis of this comprehensive knowledge base, different acknowledged expert groups have performed appraisals of research into mobile communications and health and repeatedly endorsed the exposure limits. Numerous expert bodies and authorities were unanimous in their conclusion that the state of research does not give cause to question the safety of using mobile communications provided that the exposure limits are complied. Among others these are the World Health Organization (WHO) in 2011, EU's independent scientific advisory committee SCENIHR (2014), International Commission on Non-Ionizing Radiation Protection (ICNIRP) and the German Commission on Radiological Protection (SSK) both in 2011, the UK Research Program (MTHR) in 2014, Swedish Radiation Protection Authority (SSI) in 2014, Health Protection Agency, UK in 2012 or the Health Council Netherlands in 2013.

Bundesamt für Strahlenschutz (Federal Office for Radiation Protection)

Bundesamt für Strahlenschutz (Federal Office for Radiation Protection) about 5G


EMF Portal

The Federal Office for Radiation Protection (BfS) summarizes the findings in its recent 2013 brochure as follows: "The DMF findings have greatly reduced the knowledge gaps and thus improved the data base for assessing risk. A careful review reveals that the findings do not give any cause to question the protective effect of the existing limits."

Headed by the German Ministry of the Environment, the German Mobile Telecommunication Research Program (DMF) was executed in Germany between 2002 and 2008. With a total budget of EUR 17 million, the ministry sponsored more than 50 studies to examine the effects of electromagnetic fields. Mobile network providers participated in the project financially, providing a total of EUR 8.5 million. Responsibility for technical and administrative implementation lay with the Federal Office for Radiation Protection (BfS).
Mobile communications technology is constantly evolving, while scientific methods and capabilities likewise continue to develop. From Deutsche Telekom's standpoint, further research is therefore meaningful and important. Although Germany's Mobile Telecommunication Research Program has ended, Deutsche Telekom has continued to support specific independent research, including projects launched as part of the environmental research plan by the Federal Ministry of the Environment.

German Mobile Telecommunication Research Programme (DMF)

BfS brochure (German)

So that you can use your cell phone to make or receive phone calls wherever you are, your phone needs a good connection to a base station in the near vicinity.

Each cell phone and also each base station has a transmitter as well as a receiver. High-frequency electromagnetic fields (EMF) are needed to transmit information between a cell phone and a base station. The information is then usually forwarded between base stations, and between a base station and the fixed network, over copper or fiber optic cables.
To ensure high-quality coverage, mobile communications requires a large number of base stations. Each base station can only handle a certain number of calls and transmit a certain volume of data. Each of them therefore only serves a narrowly defined area (known as the radio cell). An increasing number of users and increasing data rates therefore require a denser mobile communications network, i.e., more base stations.

In mobile communications, base stations and mobile devices automatically adjust their transmission power to individual transmission scenarios. In the case of a good connection, the transmission power is automatically reduced to a fraction of the maximum possible power. This saves cell phone battery capacity and reduces electromagnetic fields.

The transmission power of mobile communications antennas normally lies between 10 and 100 Watt.
Telekom base stations in the GSM network normally achieve transmission powers of four to sixteen Watts per frequency channel. The number of frequency channels for a GSM base station depends on the demand for phone calls and data transmission in a radio cell and lies between two and ten channels. The Telekom UMTS facilities normally have one or two frequency channels, each with a maximum transmission capacity of 20 Watts. In the case of LTE with one or two frequency channels, the transmission capacity is up to 40 Watts.

Building a mobile communications infrastructure is a complex, dynamic process in which various factors have to be taken into consideration. Deutsche Telekom sets up base stations wherever demand is high, where there are gaps in the mobile network and where the quality of the service needs improvement.

Since every base station can only handle a limited number of calls and transmit a limited volume of data, a large number of base stations are needed in places where many people make mobile calls - among them residential areas.
As it sets up the mobile communications network, Telekom collaborates closely with local authorities as representatives of the area's residents.
For example in Germany the planning and implementation cover the following steps:

  • Firstly, Telekom calculates the optimal position for every new base station within the framework of its overall network concept
  • Secondly, in accordance with the agreement reached by the mobile carriers and leading local associations, Telekom communicates its plans to the local authorities
  • Thirdly, the parties search for a suitable alternative location that is agreeable to all parties in case Telekom and local government have differing views on the chosen site. In the process, Telekom also reviews sites proposed by the local authorities and gives these preferential treatment if they are suitable. In some cases it may be necessary to obtain building permission or approval from the historical monuments, nature conservation or aviation authorities

Together with the other network operators, Telekom signed a voluntary commitment for the German Federal Government as long ago as 2001 and an agreement with the leading national associations of local authorities in Germany.

In these, the mobile carriers promised to undertake a series of measures to improve consumer and health protection, to fund research and to cooperate with local authorities on the build-out of mobile communications networks.

The implemented measures were instrumental in toning down public debate about mobile communications and in improved cooperation among all parties involved in network expansion. This has been confirmed by evaluations carried out at regular intervals by independent reviewers. To mark the 10th anniversary of this date in 2011, Germany's carriers and the Federal Government confirmed continuation of the voluntary commitment. The current report was submitted to the Federal Environment Ministry in 2020.

Bundesumweltministerium (Federal Environment Ministry): Overview of the reports on voluntary commitment (German)

Yes. Even if they have a pacemaker implant, they can still use a cell phone. A minimum safety clearance of 20 centimeters between chest and cell phone is recommended to exclude interference with the pacemaker.

You should therefore not carry your cell phone in your breast pocket. However, this is merely an additional safety precaution, since the majority of pacemakers implanted today are resistant to interference from cell phones.
Patients with other electronic implants (e.g., insulin pumps) should consult their physicians about the resistance to interference of such devices.

Electronic appliances such as TV sets, radios and cell phones can interfere with each other and thus cause disruptions. However, most of the problems reported are barely noticeable and do not impair the device's functioning. One example is interference in a radio loudspeaker when someone standing close to the radio uses a cell phone to make a call.

To prevent this, electrical and electronic devices must meet the requirements of the electromagnetic compatibility standard (EMC). These requirements are defined in the European Union's EMC Directive and on national level by EMC legislation.

Cell phone usage in hospitals depends on individual regulations. According to the latest studies, it is not necessary to prohibit the use of mobile communications in hospitals altogether, since a distance of 3 meters is sufficient so that no disruptions to medical devices will be expected.

However, disruptions to medical devices by cell or smartphones cannot be fully excluded. For this reason, their usage is usually prohibited or limited, above all in operating theaters and on intensive care wards.
Mobile communications users should always observe the regulations and usage information provided in hospitals and doctors' treatment rooms and, if applicable, switch their mobile phones off.

Cell phones can be used to make calls in cars standing with their engines switched off as well as by passengers. For reasons of safety on the road, however, laws in Germany prohibit drivers from making phone calls without hands-free equipment or a headset while they are driving. Please note also that any diversion of the driver increases the risk of accidents.

In the context of safe cell or smart phone usage, it is important to know that the exposure limits are also complied with when you make a mobile call in your car. The car's metal bodywork shields connection quality slightly. However, this does not result in any significant increase in the electromagnetic fields emitted by the cell phone. The electromagnetic fields generated during car-based phone calls can be reduced by using an external antenna.

Cell phones are a valuable resource and should not be thrown away. Deutsche Telekom supports you in recycling and in many cases ensures that used cell phones are re-used. You can hand in used cell phones in our Telekom Shops or send them to us.

The Deutsche Telekom take-back system ensures that harmful substances are disposed of in an environmentally friendly manner, recyclable materials such as precious metals are recycled and functional devices are reused. Deutsche Telekom donates the proceeds to charitable organizations to support environmental and nature conservation projects. You can find all information on mobile phone take-backs at: (German).

Circular economy

Glossary Mobile communications and Health

Third-generation mobile communications standard. UMTS/HSPA support much higher data transmission speeds (up to 42.2 Mbit/s) than the second-generation mobile communications standard (2G), the GSM standard.

4G refers to the fourth generation of mobile communications (4G for short): Long Term Evolution (LTE). See also LTE.

5G is the new generation in mobile communications. It creates the basis for new customer experiences such as augmented reality games or the networking of industrial machines and intelligent devices. In addition, the technology supports the digitization of many areas of life. Customers have been able to surf Telekom's 5G network since September 2019. Over 5G, the Telekom network achieves transfer rates of up to 1 gigabit per second at peak times. In addition to speed, the new mobile communications standard also brings higher capacities and significantly lower response times, known as latency. Basic information on the network of the future.

Agreement concluded in 2001 between the local government central associations – the German Association of Cities and Towns, the German County Association, and the German Association of Towns and Municipalities – and the mobile network operators, giving communities a say in mobile network expansion.

Denotes the maximum permissible value with which electromagnetic fields may have an effect on human beings. The basic limit is expressed as the “Specific Absorption Rate” (SAR). Since it is hard to measure in practice, reference limits are preferred. In order to take the protection of highly sensitive people into account, the basic limit includes a safety margin.

Transmitting and receiving system for mobile communications, serving a limited area (radio cell).

Regulation on the procedure for providing evidence of the limitation of electromagnetic fields.

Bundesamt für Strahlenschutz (Federal Office for Radiation Protection).

Bundesimmissionsschutzverordnung Federal immission control ordinance (EMF Ordinance in Germany).

Bundesministerium für Umwelt, Naturschutz, Bau und Reaktorsicherheit (Federal Ministry for the Environment, Nature Conservation and Nuclear Safety).

Short form: Bundesumweltministerium (Federal Environment Ministry).

Bundesnetzagentur. As a higher federal authority, the “Federal Network Agency for electricity, gas, telecommunications, post and railways” regulates such sectors as the post and telecommunications markets.

Its area of responsibility includes promoting further development of the telecommunications market through liberalization and deregulation. It is also responsible for site approval procedures when mobile communications networks are expanded.

Digital Enhanced Cordless Telecommunications: This transmission standard for cordless home phones ratified by the European Telecommunications Standards Institute (ETSI) in 1992 offers more reliable transmission and greater protection against eavesdropping than previous analog cordless phone systems. DECT phones operate in the microwave frequency range from 1.88 GHz to 1.9 GHz and have a transmit power of 0.25 W.

In contrast to analog transmission, digital networks transmit information (voice, images, sound) using the binary digits 0 and 1.

These networks include Germany's D-Netz and E-Netz, which are used in mobile communications.

The term "downlink" denotes the radio link from a base station to a mobile device (e.g., cell phone or smart phone).

Digital Subscriber Line: A technology that can be used to provide domestic users and small businesses with greater transmission bandwidth over conventional copper-wire telephone lines. See also ADSL.

In mobile communications, base stations and mobile devices automatically adjust their transmitting power to suit individual transmission scenarios.

Electroencephalogram, method used to measure the brain's electrical impulses.

Electromagnetic fields.

In mobile communications, emission refers to the sending out of radio waves or electromagnetic fields.

Germany's EMC Act relating to the electromagnetic compatibility (irradiation immunity) of technical devices, dated Sep. 18, 1998.

EU Directives on the electromagnetic compatibility of technical devices (89/336/EEC) dated May 3, 1989.

Electromagnetic Environmental Compatibility. Analyzes and evaluates the impact of electromagnetic fields on people and the environment.

The (intended or unintended) exposure of an organism or its substructures to external influences (in mobile communications: electromagnetic fields).

Measures the strength of an electromagnetic field; measured in volt per meter (electric field) and ampere per meter (magnetic field).

EMC database at Germany's Research Center for Bioelectromagnetic Interaction (FEMU) at the Rheinisch-Westfälische Technische Hochschule Aachen.

Measures the change in electromagnetic fields over time; measured in cycles per second (Hz).

The available frequency bandwidth used to transmit data. Generally speaking: The broader the spectrum, the higher the data rate that can be achieved if the same transmission technologies and parameters are used.

General Packet Radio Service is a data transmission technology for mobile communications networks, e.g., for transmitting Internet pages to cell phones.

Global System for Mobile Communications (formerly Groupe Spéciale Mobile (GSM)) is a standard for full-digital mobile communications networks that are mainly used for telephony as well as for line-switched and packet-switched data transmission and for text messages (SMS). It is the most widely used worldwide mobile communications standard.

HotSpots are locations that provide users with high-speed Internet access via WLAN. All HotSpots can be found at

High Speed Downlink Packet Access.

Mobile communications technology which increases transmission rates in the UMTS network. This further development of UMTS enables data transmission on downlinks at realistic data rates of up to 14.4 Mbit/s.

High Speed Uplink Packet Access - Increases the transmission rates on uplinks in the UMTS network, thereby allowing shorter latency (delay times). Data can be transmitted at speeds of up to 5.8 Mbit/s.

Electrical appliances are built so that they cannot be interfered with by other devices outside legally prescribed safety areas. For medical devices, the DIN-EN 60601-1-2 standard specifies electromagnetic compatibility (irradiation immunity) of 3 V/m, for life-sustaining medical devices there is a standard of 10 V/m. The minimum recommended distance between a cell phone and a non life-sustaining device is three meters.

International Agency for Research on Cancer – an institute of the World Health Organization (WHO).

International Commission on Non-Ionizing Radiation Protection.

The impact of factors such as noise or electromagnetic fields on the organism.

Measures the degree to which a system is influenced by electromagnetic fields (see also Irradiation immunity).

Process whereby one or more electrons are removed from an atom or molecule. Ionization can be caused by high temperature, electrical discharges, radiation or chemical reactions.

Radiation is referred to as ionizing once exposure can damage cell material. Electrons are removed from the cell's molecular structure, thus damaging the cell. Only electromagnetic fields with wavelengths shorter than UV light can have an ionizing effect.

Legally specified value below which, according to current scientific findings, effects on people's health can be precluded. The purpose of limit values is to protect people's health. In mobile communications, there are basic and reference limits.

Long Term Evolution.

Fourth-generation mobile communications standard and further development of UMTS. LTE is based on the transmission method which digital broadcasting, for instance, also uses and enables data rates of up to 100 Megabit/s on the downlink.

Multiple Input, Multiple Output is a multiple antenna technology used with LTE. It makes it possible to increase both the data rate and the quality of the service.

Process during signal transmission whereby low-frequency information (e.g., music, voice, data) is modulated to a suitable high frequency, known as the carrier.

Next Generation Mobile Networks is a consortium in which various mobile communications providers have joined forces to drive the further development of UMTS to the next generation. One development in this context is LTE.

Covers all fields of the electromagnetic spectrum which do not have enough energy to cause ionization. These include radio waves, microwaves, infrared and visible light.

Possible effects of electromagnetic fields causing no, or a non-measurable, rise in body temperature. Their existence is the subject of controversial discussion amongst scientists and is not considered to be scientifically proven.

Orthogonal Frequency Division Multiplexing.

Radio transmission method which – for example in LTE – divides the frequency spectrum into narrowband subchannels to transmit data over these channels in parallel. This makes it possible to adjust the radio channel optimally to the signal propagation conditions and to increase transmission capacity.

Measures the intensity of an electromagnetic field; measured in watt per square meter.

Each base station only serves a narrowly defined area, the radio cell. Seen together, adjacent radio cells form a full-coverage network structure.

Since basic limits are often hard to measure and examine, limit values are derived for their "inducing factors” instead. These reference limits apply to the electric and magnetic field in the free space outside the body. They guarantee that under no circumstances are the basic SAR limits exceeded within the body.

Specific Absorption Rate.

It measures the electromagnetic fields absorbed by the body. It is represented in watt per kilogram of body weight.

Approval granted by the Federal Network Agency to set up a base station. This process is specified in the Ordinance on the Method of Proof for the Limitation of Electromagnetic Fields (BEMfV).

Deutsche Strahlenschutzkommission.

German Commission on Radiological Protection; advises the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU) on all matters relating to radiation protection.

Effects caused by electromagnetic fields which lead to a rise in body temperature.

Universal Mobile Telecommunications System is a third-generation (3G) mobile communications standard.

Radio link from a mobile device (e.g., cell or smart phone) to the base station.

Regions (e.g., cities and municipalities) that the States of Germany have reported to the Federal Network Agency as having inadequate broadband Internet coverage (fixed network or mobile communications) are referred to as "white spots." These regions are mainly located in rural areas; coverage is being expanded as part of Telekom’s "More Broadband for Germany" project.

Wireless Local Area Network is a radio standard for wireless data transmission in a small-scale local radio network. A WLAN includes an access point - a WLAN router. The router establishes a connection to the Internet. A WLAN-capable device, for example a laptop with a WLAN adapter, is also required.

World Health Organization.

Deutsche Telekom Technik GmbH

EMF, Environment & Sustainability


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