[Dr. Sivana]

The fact is there is virtually nowhere on this earth you can escape EM fields without a Faraday cage.

The lady's bathroom WAS covered in aluminum foil.

I had wondered about the wifi sensitive who have cell/AM/FM/Shortwave/TV/emergency bands/Ham signals, not to mention the signals made by, say an AC compressor.

[Gaffer]

It all depends on how the aluminum was sealed (RF sealed with conductive sealant). If it was just a bunch of pieces of aluminum foil taped up in odd sizes, it is highly likely they could just become re-radiators of whatever EM of the right wavelengths struck them. In order to effective they must be perfectly RF sealed at each point where they overlap.

There are also several anecdotal sources and academic treatments out there on the web, too. Here’s a real world test one guy did.

http://www.omniscienceisbliss.org/rfid.html