For a long time, the microwave oven has been a very useful kitchen appliance. However, there are quite a few rumors and worries related to the leakage of radiation waves from microwave ovens.
Recently on the internet or TV it was reported that when you put the phone in the microwave (it’s off) and call. If your phone rings, the microwave has leaked and could be dangerous.
Microwaves are devices that emit ultra-high frequency waves, operating at a frequency of about 2.45GHz. Electromagnetic waves cause water molecules in food to heat up.
To ensure that this electromagnetic wave affects only the food in the oven, the microwave oven is designed as a Faraday cage. The glass door screen connects to the metal body to create a protective layer, shielding electromagnetic waves from spreading around.
Meanwhile, your mobile phone operates at a lower frequency, around 1.9GHz or 0.85GHz for CDMA networks. Therefore, the microwave shield is not designed to block mobile waves.
In addition, Wifi operates at the same frequency of a microwave oven, around 2.4GHz. Testing a microwave with Wifi makes more sense than a regular cell signal.
But the capacity of Wifi transmitters is very small, if you sit by the Wifi transmitter all year, it is only equivalent to making continuous phone calls for 20 minutes.
When you put your phone in the microwave, if you turn on Wifi and make calls over the internet, for example Zalo, Viber software, there is still a possibility that your phone will ring. But no need to worry, microwave ovens are not completely shielded from electromagnetic radiation.
During the manufacturing process, depending on the regulations of each country and the manufacturer, microwave ovens are allowed to leak a small amount of electromagnetic radiation.
Of course, the leakage level is low and safe for the user. For example, in the US, the maximum radiation leakage is 1mW/cm2 for new microwave ovens and does not exceed 5mW/cm2 for old ovens.
If you have a dedicated electromagnetic radiation meter, place it in front of the microwave and measure. If the result is up to 20mW, don’t worry too much. Air traffic control stations at airports emit radiation up to 100mW.
As such, checking for microwave leaks by phone is unreliable and you shouldn’t be too worried when your phone rings in the microwave.
However, for safety, users of medical devices such as pacemakers should not stand near microwave ovens to avoid interference with control waves. In addition, do not put any metal objects in the operating microwave oven to prolong the life of the microwave oven.