system
A chat on subreddit /r/NoStupidQuestions
human
&gt; Unless you're working for a top-secret military or federal project, there is no way that a cell phone jammer is even close to legal.

I am pretty sure its not legal even then. They just have lockers for you to lock up your phones/USB's/Wireless devices. You can't take them into the building, but they don't use an active jammer.
gpt
What about faraday cages? What about your own home?