They'll be safe. ;)
Also: Electromagnetic Pulse - EMP Myths - futurescience.com
[Taken with a huge grain of salt.]Quote:
There is truth to this recommendation (if there were a way to know that a burst was about to happen). Equipment is more vulnerable if it is operating, because some failure modes involving E1 HEMP trigger the system's energy to damage itself. However, damage can also happen, but not as easily, to systems that are turned off.
In conclusion: An EMP would do [censored] all.