Options for reducing exposure when using the mobile phone

Mobile communications use high-frequency electromagnetic fields to transmit information. Mobile phones generate these fields directly by the head when making telephone calls without using hands-free equipment. The amount of energy the body absorbs from these fields in a given time is referred to as exposure. According to current scientific knowledge, the internationally recommended limits are sufficient to protect against proven health risks. Even if no further measures for radiation protection are necessary, there are still individual options for reducing exposure.

Reduce field strength and shorten exposure duration

The high-frequency electromagnetic fields emitted by cell phones when making calls are generally much stronger than those emitted by mobile phone base stations when transmitting. The possibilities for reducing exposure described here by the BfS therefore relate to cell phone use and are intended to reduce the field strength and shorten the duration of exposure:

• So you can use the landline phone if you have the choice between landline and mobile.
• You can also keep phone calls short with your mobile phone.
• Another way to reduce exposure is to avoid making phone calls in the event of poor reception, such as in a car without an outdoor antenna. The worse the connection to the nearest mobile base station, the higher the transmitting power of the mobile phone – and thus the strength (intensity) of the high-frequency electromagnetic fields. The car body, for example, deteriorates the connection and the mobile phone therefore sends with a higher performance.
• You can compare cell phone models and use cell phones where your head is exposed to lower high-frequency electromagnetic fields than other models. The lower the SAR (Specific Absorption Rate) value of your phone, the lower the high-frequency electromagnetic fields. The SAR values of the available mobile phone models can be found in the SAR list. The manufacturers of the mobile phones usually indicate the SAR values determined under specified conditions in the instructions for use. Corresponding information can also often be found on the websites of mobile phone manufacturers.
• You can also use a headset. The intensity of the high-frequency electromagnetic fields decreases rapidly with the distance from the antenna. By using a headset, the distance between the head and antenna is greatly increased. The head is therefore exposed to lower high-frequency electromagnetic fields when making calls.
• You can write text messages instead of making phone calls because you won't be holding the phone on your head.

With these options, personal exposure can be easily and efficiently reduced without sacrificing the benefits of a mobile phone.

Electronic implants

Electronic devices can react more sensitively than the human body high-frequency electromagnetic fields. An example is an implanted pacemaker, which under adverse conditions can be interrupted in its function. Interference effects from mobile phones have been observed on individual pacemakers at a distance of maximum 20 cm between the devices. Those fitted with cardiac pacemakers should guard against this and not keep their mobile phones directly by the upper body, i.e. for example not carry it in standby mode in their jacket pocket. At the usual distance of more than 20 cm between mobile phone antenna and pacemakers, normal telephone use has no effect on the cardiac pacemaker.

Hearing aids

Noise interference can occur when hearing aids are used close to mobile communications devices. To avoid this, you can keep your distance or, if you want to make your own phone calls, turn off the hearing aid.

In hospital

Problems can also occur through mobile phone use in hospitals. Occasionally, sensitive medical equipment can suffer interference even at a distance of 1 to 2 metres. Take care to ensure sufficient distance from sensitive medical electronic equipment - in particular in intensive care wards and operating theatres. Mobile communications bans in hospitals are therefore to be strictly adhered to.

In aircraft

To avoid interference to onboard electronics, the use of mobile phones during flights must be restricted (Article 27, Para. 3 of the Air Traffic Act). In Germany it is usual to prohibit their use during take off and landing. During the flight however, the airline can enable the use of mobile phones.

In the car

The prohibition of the use of mobile phones without hands-free equipment when driving is justified by the associated distraction of the driver. As a distraction occurs even when hands-free equipment is used, making calls while driving should be avoided as far as possible.