You certainly know it: connected devices communicate with each other with radio waves (called radio frequencies), and your smart watch is obviously no exception to the rule. However, should you be so afraid of these electromagnetic waves that you should limit their potential harmful effects by removing your watch before going to bed? Not really, and we’ll explain why.
Its power is very low
Admittedly, it is true, as Anne Perrin explains, that “radio frequencies are partly absorbed by the body. These waves can cause matter to heat up if the amount of energy absorbed is high enough”. And said heating can, from a certain level of exposure, lead to health effects. But good news: “The amounts of energy emitted by smartwatches are low. About the same as Bluetooth earpieces. The range is short.”
Short, you do not risk boiling tomorrow by checking your emails. As proof, we want a comparison with another everyday object: “A microwave oven also uses radio frequencies. It emits between 700 and 1000 watts in an enclosed space to heat food, explains the expert. On the other hand, a Wifi box often operates at the same frequency as the oven, but its power is around 100,000 times lower (100 milliwatts maximum). It is impossible to heat water with WiFi!“. The balance sheet is therefore without appeal: “I think there is no reason to be concerned given the powers involved and the levels of exposure caused by these connected devices.”
Strict standards
Beyond these questions of power, also know that all of this is obviously very framed. There are therefore regulations* that manufacturers must imperatively apply in order to obtain authorization to market wireless devices. “For the public, we establish thresholds 50 times lower than the level where the first effects due to heating appear, which are not yet burning effects.”
Mobile phones, tablets and other connected watches must therefore not exceed SAR limit values (for Specific Absorption Rate): “this ensures that the amount of energy absorbed, in watts per kilogram (W/kg), into the human body is not sufficient to cause health effects.”
Furthermore, note that “As of July 1, 2020, SAR values must be displayed for any additional wireless device with a power greater than 20 milliwatts that can be used within 20 cm of the body.”
In short, you will understand, you can logically continue to wear your watch day and night. However, be careful: if you have an electronic medical implant, such as a pacemaker, “it is recommended not to place the connected devices within 15 cm of the implant due to interference that may occur between the devices.”
*In France, the ANFR (National Frequency Agency) is responsible for verifying that these standards are respected
Read also:
- Is 5G dangerous for health?
- Phones with 5G do not pose more health risks, according to initial tests
- Are sleep apps reliable?
