What are the safety measures in mobile communications?
Time and again, questions are asked about the safety of radio waves from mobile communications; do they pose a health risk or not? For decades scientists have searched intensively for potential health risks that may be traced to mobile communications. So far, there is no scientific proof that the radio waves used in mobile communications harm health or well-being. The prevailing scientific opinion is that the existing exposure limits are sufficiently high to protect the public from any adverse effects.
The German Mobile Telecommunication Research Programme
Public health protection was one important goal for the initiation of the German Mobile Telecommunication Research Programme (Deutsches Mobilfunk Forschungsprogramm – DMF) in 2002. The DMF, which concluded its work in 2008, remains the largest and most extensive research project on this area in Germany to date. A total of 54 research projects on different topics in biology, epidemiology, dosimetry and risk communication were carried out under the impartial supervision of the Federal Office for Radiation Protection (Bundesamt für Strahlenschutz – BfS).
In its final statement in 2008, the German Commission on Radiological Protection (Strahlenschutzkommission des Bundes – SSK) stated that „the initial fears of health risks could not be confirmed. Nor have the research findings of the DMF led to any new indications of health impacts that have not previously been considered“.
Evaluation of the World Health Organization
In June 2011, the WHO updated their fact sheet no. 193 on electromagnetic fields and mobile phones and stated that „to date, no adverse health effects have been established as being caused by mobile phone use“. The reason for the update was an evaluation published by the WHO’s own cancer research agency, the International Agency for Research on Cancer (IARC). In May 2011, the IARC had classified radio-frequency electromagnetic fields produced by mobile phones as “possibly carcinogenic to humans”. The IARC based this evaluation on a limited number of indications in some epidemiological studies, which were not, however, supported by results from experimental studies. The agency did not give any information about the amount of exposure, the strength of the effect and thus the extent of a possible risk for the public.
Safe distances are defined to protect the general public by ensuring that the legal exposure limits for electromagnetic fields are always observed in all populated areas.
Where do safe distances exist?
Safe distances exist around all antennas of mobile phone base stations. The Federal Network Agency for Electricity, Gas, Telecommunications, Post and Railway (Bundesnetzagentur) determines the safe distance for each antenna site individually. The calculation takes into consideration the antenna type and its transmission power. Typical safe distances around mobile phone base stations are between 2 and 8 metres horizontally. By comparison, powerful radio and television transmitters require safe distances of up to several hundred metres.
Beyond these safe distances, the strength of the electromagnetic fields always remain below the legal exposure limits. There are no adverse health effects for people staying in these areas permanently.
The distance from a mobile phone base station is not a reliable criterion for estimating its emission. Because of the radiation characteristics of the antenna and the topographic characteristics of its surroundings, the field strength is often lower in the immediate vicinity than further away. In principle, it must be said that all the power flux densities measured at different distances only reach a fraction of the legally established exposure limits.
Mobile network operators are obliged to put up special signs at their antenna locations, which also need to be secured. This is to ensure that no-one is able to remain within the safe distance around a mobile phone base station accidentally or without authorisation.
Mobile phone users do not need to observe any special safety measures. With their low transmission power of two Watts maximum, all mobile phones lie below the exposure limits, meaning that safe distances are not required. It is theoretically possible to use a mobile phone around the clock without having to fear any adverse health risks.
Safety for implants
People fitted with implants such as pace makers can also use mobile phones. The Federal Office for Radiation Protection recommends a safe distance of about 20 centimetres. There are also certain places such as hospitals or aeroplanes that work with sensitive electronics and where safety precautions require that mobile phone users observe certain rules.
Mobile phone ban in aeroplanes
For safety reasons, it is not permitted to use mobile phones in aeroplanes. The reason lies in the fact that the radio waves could interfere with several of the safety-relevant instruments on board the aircraft that rely on sensitive electronics.
Hospitals and doctor‘s offices
A large number of medical devices, among them life-sustaining systems, rely on sensitive electronics. Mobile phone use can cause interference in the immediate vicinity of 1-2 metres. It is therefore essential that mobile phone users observe the existing rules and turn their mobile phones off in hospitals and doctor‘s offices, if at all possible.
Mobile phone antennas near hospitals or doctor‘s offices, such as on the roof of a neighbouring building, do not interfere with medical devices. The interference of electrical devices is regulated by the standards and laws on electromagnetic compatibility (EMC). As long as a device complies with the immunity limits established in these laws and standards, it will not be susceptible to interference from mobile phone base stations’ emissions. This is also due to the fact that mobile phone antennas operate at very low transmission power and the intensity of the electromagnetic fields around them falls quickly as the distance increases.
Mobile phone ban at filling stations
The ban of mobile phone use at filling stations is not related to the electromagnetic fields of mobile phones. Here, the danger lies with the rechargeable battery, as with all electrical mobile devices: If a mobile phone is dropped on the ground during a call and the battery falls out, it is possible that it might send out sparks that could cause the inflammable gases from the tank or the petrol pump to explode. This remains theoretical, as no such accident has ever happened worldwide.