Here's an alternative theory - no idea whether it's true but it's somewhat plausible... One of the twists of operational aviation meteorology is the diurnal effects on atmospheric pressure caused by daily heating/cooling.
http://www.eclipse2006.boun.edu.tr/sss/paper01.pdf
Personal perspective here... I'm military and have worked in sensitive access areas, so I can relate.
There is a standing rule that ANY electronic brought into one of these secured areas requires prior permission. They do not deny entry to everything - only those things which people could either intentionally or unintentionally use to "easedrop" or spy.
Everyone seems to think that they worry too much about simple things, but here's why... The military performs testing on zillions of electronic devices to determine their weaknesses. They have determined that many communication devices can be hacked or easedropped on without the user's permission - and in a few cases, even when the phone is "off" but battery is still installed. Now, I drag a 12-pack of Coke into my cubicle and set it right next to my classified phone. There's a possibility that someone taps in and intercepts my Coke-phone and listens in on all my classified discussions. No matter how remote the chance, the government will NOt allow this possibility - hence all the fuss about the cans.
Now, just imagine how that cell phone can be used against you by your unscrupulous employer...
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Here's an alternative theory - no idea whether it's true but it's somewhat plausible... One of the twists of operational aviation meteorology is the diurnal effects on atmospheric pressure caused by daily heating/cooling. http://www.eclipse2006.boun.edu.tr/sss/paper01.pdf
There is a standing rule that ANY electronic brought into one of these secured areas requires prior permission. They do not deny entry to everything - only those things which people could either intentionally or unintentionally use to "easedrop" or spy.
Everyone seems to think that they worry too much about simple things, but here's why... The military performs testing on zillions of electronic devices to determine their weaknesses. They have determined that many communication devices can be hacked or easedropped on without the user's permission - and in a few cases, even when the phone is "off" but battery is still installed. Now, I drag a 12-pack of Coke into my cubicle and set it right next to my classified phone. There's a possibility that someone taps in and intercepts my Coke-phone and listens in on all my classified discussions. No matter how remote the chance, the government will NOt allow this possibility - hence all the fuss about the cans.
Now, just imagine how that cell phone can be used against you by your unscrupulous employer...