Presented as the miracle solution against the waves emitted by smartphones, the anti-wave patches touted by many influencers are not only useless, but also dangerous. Accessories to avoid!
Between smartphones, tablets, computers, Internet boxes and connected objects of all kinds, the waves have never been so present in our daily lives, especially in our homes. This overexposure to electromagnetic fields raises many questions and worries, in particular about their impact on health, especially among people who claim to be electrosensitive, who suspect radio waves of causing headaches, tinnitus, sleep, even infertility, miscarriages and tumors. The subject has been debated for years and countless studies have been carried out by all kinds of organizations without reaching clear conclusions – this is the case of the National Health Security Agency (handles) who published some documents on exposure to waves.
Faced with this controversy and the real or supposed risks, a market for protection against waves has gradually developed. And this is how we have seen the appearance of anti-radiation patches for smartphones: small devices which come in the form of self-adhesive pads to be placed in a specific place on the back of a mobile phone and which promise to protect the user from electromagnetic waves. Sold for a few tens of euros, often promoted by influencers with a lot of attractive promo codes, they mainly target electrosensitive people, pregnant women and young people, heavy users of smartphones. The best-known brand in France is Fazup, which claims more than a million consumers and which ensures that the waves emitted are reduced by up to 96%. But what is it really?
Electromagnetic waves: when power rhymes with distance
First of all, remember that we are constantly bathed in electromagnetic waves – “oscillating electric and magnetic fields” which propagate through space carrying a form of energy. Some are natural – like the waves of light from the Sun –, others artificial, that is to say from systems created by Man – like the radio waves used by terrestrial television. In general, most electrical and electronic devices are sources of electromagnetic fields – televisions, refrigerators, cooktops, speakers, etc. – if only by their power system. However, there are big differences between household appliances and wireless communication systems that use radio waves, especially smartphones.
To communicate over mobile networks, smartphones use electromagnetic waves in the radio frequency spectrum – these are the waves that carry data. But unlike a television or a radio, which are only receivers, a telephone is also a transmitter: its internal antenna – a simple metallic circuit – is used both to capture and to send waves. And that’s what makes all the difference with most electronic devices. Because to detect and join the relay antennas of the mobile network, often located several hundred meters away, the smartphone sends its signals with a certain power. However, the greater the power of said signal, the greater its impact on nearby bodies.
And that’s the whole problem. It should be known in fact that the power of a radio wave midnight quickly with distance – it is inversely proportional to the square of the distance which separates the receiver from the source. This is why a user on the phone is more exposed when the device is glued to the ear than when it is in loudspeaker mode. The worst is when the smartphone is glued to the body for a long time, in a pocket, especially when the relay antenna is far away… A problem that does not arise in the same terms with other wireless systems using radio waves, such as Bluetooth headphones, short-range devices, which work with low-power radio waves.
Danger of radio waves: the precautionary principle
Many studies have been conducted over the past two decades to determine whether cell phones pose a potential health risk, including the development of brain tumours. Ihe World Health Organization (WHO) has classified the waves emitted by smartphones as “potentially carcinogenic” because, to date, iIt has never been established that they can be the cause of a harmful effect on health – it is necessary to wait to be able to observe any effect on the long term. The limitation of exposure to the waves emitted by the smartphone is therefore based on a precautionary principle.
Limitations are already in force with the Specific Absorption Rate (SAR). This is an indicator that makes it possible to assess the quantity of waves emitted by smartphones and other connected objects, and therefore the quantity of energy absorbed by humans. It can be found on the sheet of each smartphone, alongside the technical characteristics. The lower this indicator, the better. Manufacturers are required to respect a limit of 2 W/kg (watts per kilogram) for the head and the torso, and 4 W/kg for the limbs, a limit which takes into account the evolution of models and uses of the smartphone and corresponds to the “worst cases”, when the device transmits at maximum power for the duration of the test, which therefore does not correspond to actual use. These measures are taken as a precaution in view of the uncertainties and the lack of scientific hindsight, as recalled by the National Agency for Food, Environmental and Occupational Health Safety (ANSES) in 2019.
Anti-radiation patch: a device that increases exposure
We can legitimately say, even if the impact of exposure to waves emitted by smartphones on health is not recognized as problematic by scientific studies, that prevention is better than cure. But are the famous anti-radiation patches really effective? The National Agency for Food, Environmental and Occupational Health and Safety (ANSES) looked into the issue in his work in 2013. She examined several anti-radiation devices and found that those “intended to be placed on or near the antenna of the mobile phone do not show significant protection efficiency for all the mobile phones and frequency bands tested. No conclusion can therefore be drawn as to their efficiency on a decrease in the level of SAR.“
The Directorate General for Competition, Consumer Affairs and Fraud Prevention (DGCCRF) has for its part carried out a survey in 2015 on the conditions for the marketing of “anti-radiation” devices for mobile telephones. She notes that the majority of companies selling this type of device are based on the feelings of users – the famous placebo effect? – and not on scientific measurements. As for those who take action, the conclusion is clear: “SAR tests generally do not reflect the true effect of anti-radiation devices which, in some cases, may have an effect contrary to that claimed, by increasing the level of exposure to radio frequencies during the use of mobile phones, due to the degradation of phone signal performance they can cause“.
Same conclusion in a survey conducted by 60 million consumers end of 2022: not only are the anti-radiation patches not effective, but they are also dangerous. Guy Pujolle, professor of computer science at the Faculty of Science and Engineering at Sorbonne University, explains to the magazine that “these patches are counterproductive” because “if we prevent a phone from transmitting, it will increase its power, showering the user with waves more strongly.” Clearly, as the propagation of waves between the antenna of the smartphone and the transmitting antenna is hindered by the anti-wave patch, the device emits even more waves to be able to overcome the obstacle and maintain the connection to the network. .. In other words, the cure is worse than the disease!
In practice, there are a few simple principles to apply to limit exposure to electromagnetic waves emitted by a smartphone.
- Turn off the smartphone as soon as you don’t need it: it then no longer emits or receives any radio waves!
- Switch to airplane mode as soon as possible – especially at night – which has the effect of cutting off all wireless communications (see our article). It is even possible in this limited mode to activate Wi-Fi and/or Bluetooth, which generate less powerful waves than those of mobile telephony.
- Hold the smartphone away from your body – more than 1 m – when it is on the mobile network, using a hands-free kit or wired headphones to make calls for example, and holding it away from your head to surf the Internet .
- Avoid phoning with your ear glued to your smartphone while on the move. Because when it moves, the device must constantly seek new relay antennas to maintain communication, often using its maximum power: this is the worst situation!.