On Sun, 03 Mar 2013 08:37:20 -0500, Kurt Ullman
wrote:

In article ,
micky wrote:


Just for the record, I was told the MRI machines were magnetic even
when they are off.. That's why I think they won't let me in the room
just to look at a machine with no one in it, until I've undressed.
They let me look at it through a window.

Yep. That is because it is never off, it is just in standby. From my MRI
safety lectures in the past, IIRC, to turn it all the way off there is
an emergency "quenching" that stops the superconducting magnets from
conducting but it take a while, and a whole bunch of money, to bring it
back online.

Thanks. Someone at the MRI office said they were permanent magnets,
but I suspect she was just guessing. Probably never had to do the
emegency shutdown.