Do you use a Faraday Cage in your day-to-day life?

This question may seem a bit odd for some of you, but the fact is that most of you do! Passenger compartments of automobiles and airplanes are essentially Faraday Cages, protecting passengers from electric charges such as lightning. A senior friend told me that when lightning occurred while he was travelling in an aeroplane, he could see the lightning skim along the side of the plane, with nobody inside getting hurt. It is often mentioned that when you are on the road during a lightning storm, you are better protected while inside your car. So what is this Faraday Cage? Way back in 1836, Michael Faraday observed that excess charge on a charged conductor resided only on its exterior and had no influence on anything enclosed within it. Since the days of Michael Faraday, there have been demonstrations of enclosing volunteers in Faraday Cages and showing protection from great electrical discharges.

The Faraday Cage need not be built of solid metal, but the holes in the mesh should be smaller than the wavelength of the electromagnetic interference it is meant to protect from. That is why mobile phones working on multiple frequencies, could still work while inside a Faraday Cage. Higher frequencies would get through, while lower frequencies will not, depending on the mesh size.

Faraday Bags designed on similar lines have been used to protect highly sensitive digital information from being accessed remotely, including the prevention of RFID skimming. Important electronic components used in automobiles and aircrafts may also use Faraday Cages to prevent electromagnetic interference. These may include wireless door locks, navigation and GPS systems. Many of you would have noted lack of cell phone coverage inside lifts or elevators, due to the Faraday Cage effect of the metallic enclosure. Faraday suits are sometimes used by linemen for protection against electric shocks while working with high voltage lines. Another important application is the Faraday Cage around MRI (Magnetic Resonance Imaging) rooms to prevent artifacts by picking up external radiofrequency signals.

Even the microwave oven at home has a Faraday shield on five interior sides and a partial Faraday cage consisting of a wire mesh on the sixth side which is the transparent window, to protect the user from exposure to microwave radiation. So there is a long list of Faraday Cages in our day-to-day life, though most of us are not aware of it!