Options for reducing exposure when using smartphones or tablets

Just like classic mobile phones, smartphones use 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 LTE or 5G standard emit less radiation

Modern mobile communications devices have an advantage over older models: They often transmit using LTE standard, or more recently also using 5G standard. Compared to the GSM standard, these standards generate lower levels of electromagnetic fields 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 LTE or 5G 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 (i.e. periods of more than 15 years). 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 specific absorption rate values, SAR for short, when purchasing can reduce individual 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 0.5 watts per kilogram for the use case "holding the phone right next to the ear during a call". 41 per cent of currently available smartphones can be classified as "low-radiation" regarding this use case. SAR values of mobile communications devices currently on the market are published at www.bfs.de/sar-werte-handy.

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. Formerly the measurement norm enabled a measurement distance of up to 2.5 cm. In everyday life, however, smaller distances than 2.5 cm between body surface and device occur very often. According to the European standard EN 62209-2 the manufacturers determine the SAR values for the use case "Wearing the phone on the body at a standardised distance of 0.5 cm. Therefore, the values for the respective use cases can be compared with each other.

When tablets have mobile communications inbuilt, they must likewise comply with the SAR limit value.

Options to reduce exposure when making phone calls and surfing

No further measures are necessary to protect yourself from the high-frequency electromagnetic fields when using smartphones or tablets. However, there are other ways to reduce exposure:

• You can make calls with a headset. This applies to smartphones as well as classic mobile phones.
• You can focus your mobile internet use on situations where reception is good or Wi-Fi is available. With WLAN, the transmission power is usually lower than with the mobile communications standards GSM, LTE or 5G.
• Likewise, you can only access your emails manually if necessary.
• Another way to reduce exposure is to avoid e-mail retrieval while you are on the phone. If you personally want to expose yourself to high-frequency electromagnetic fields particularly little, you can turn off background traffic.
• If you wear your smartphone on your body, pay attention to the minimum distance specified by the manufacturer. If necessary, use the included carrying accessories.
• Furthermore, when surfing the Internet with your tablet or smartphone, you can pay attention to a sufficient distance to the body. Exposure to high-frequency electromagnetic fields decreases significantly the greater the distance.
• You can pay attention to the lowest possible SAR value when buying.