Is it permitted to installed a duplex receptacle under a raised floor and pass a cord through the tile to feed a workstation?
(This is not an enviromental air plenum)
Good question.
Is this one of those "tile" type floors like you have in computer rooms? I would think that the AHJ would prefer the receptacle to be mounted on or above the finish (raised) floor, for easier inspection/access.
If I was faced with this situation, I'd probably surface mount a J-box (or dedicated duplex box) to the tile, and attach that to the existing "sub" (real) floor mounted raceway system by means of MC/flex.
The closest ref. I can find is Underfloor Raceways (390).
When in doubt... ask your AHJ?!
400.8(2).
BTW: I'm a big fan of your music
The general answer is as stated by Ryan. There is a possibility that this can be done if you are in compliance with Article 645, and the cord is listed as Data Processing Cable.
Thanks to all, additional comments are welcome.