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Smartphones and tablets – tips to reduce radiation exposure

Eine Frau bei der Nutzung eines Tablets Tablet-Nutzerin

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.

Smartphones, mobile phones and tablets using the UMTS or LTE standard emit less radiation

Modern mobile communications devices have an advantage over older models: They often transmit using UMTS standard, or more recently also using LTE standard. Compared to the GSM standard, these standards generate lower levels of radiation when forming connections.

GSM standard uses maximum power when setting up the call. Thereafter, the device regulates itself to the necessary transmission power. When using UMTS or LTE standard, the mobile communications device operates in precisely the opposite way. It begins making the connection using the lowest transmission power and then increases it to the necessary power.

According to the current status of science and technology, there are no health risks posed by mobile communications. However, the technology is still too new for a conclusive judgement of long-term effects. All questions relating to the effects on children have likewise not yet been conclusively answered. Therefore the Federal Office for Radiation Protection supports further research in these areas and advises users not to disregard precautionary measures.

Take note of low SAR values when purchasing

Taking note of low SAR values when purchasing can reduce individual radiation exposure. The BfS gathers information on the SAR values of all mobile communication devices that are available on the market (mobile phones, Smartphones and tablets). A device is considered to be low-radiation up to a SAR value of 0.6 watts per kilogram. 58 per cent of currently available smartphones can be classified as "low-radiation". SAR values of mobile communications devices currently on the market are published at

The table also shows the SAR values for operation of the device on the body (body worn). The SAR value, as given by the manufacturer, is supplemented by the relevant measurement distance. The highest SAR value of 2 watts per kilogram must also be maintained during operation of the device on the body. The measurement norm thus enables a measurement distance of up to 2.5 cm. When tablets have mobile communications inbuilt, they must likewise comply with the SAR limit value.

Lowering individual radiation exposure

Through our own behaviour, we can reduce our exposure to radiation in daily life. Besides the Recommendation for making telephone calls on mobile phones, there are special tips for the new applications that are offered by smartphones and tablets:

  • Make calls using a headset. This applies to smartphones as well as to classic mobile phones.
  • Surfing on the internet and accessing e-mails should if possible be done only when there is good reception or using wi-fi. Wi-fi networks usually have a lower transmission power than the mobile communication standards UMTS, GSM or LTE.
  • Access e-mails manually only when necessary.
  • Avoid receiving e-mails during a telephone call. If you wish to keep your personal radiation exposure particularly low, switch off background data traffic.
  • If you carry your smartphone on your body, take care to observe the minimum isolation distance given by the manufacturer. Use the carrying accessories supplied with it.
  • When surfing the internet with your tablet or smartphone, take care to maintain sufficient distance from your body. Exposure to high frequency fields is reduced significantly with increasing distance.
  • When purchasing, look out for the lowest possible SAR value.

Smartphones and tablets for children?

It is particularly important to minimise children's exposure to radiation. They are still developing and could therefore react more sensitively in terms of health.

Recommendations especially for children and young people

Deactivate "data transfer via mobile communications". This leaves your child able to receive calls and play games offline while on the move. If playing games online on the smartphone or tablet is absolutely desirable, this should be done at home via a wi-fi connection. The duration of play should be kept within limits not only for reasons of radiation protection.

State of 2017.10.06

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