No one is saying what level. Confidential as such requires no background checks for reader or handler. A ships Plan of the Day, a rating/MOS training manual, Sit_Reps of machinery etc, and other such communications. Secret and Top Secret are the biggies in classified material. Oh and the two highest are encryted. You're not just gonna pick it up and read it.
Excuse me, all I did was Confidential at a major shipyard, and that was a pain. What do you mean, no background check?
We all had locked cabinets we had to unlock and r e lock just getting something out. We had to be with the document at all times if not locked up. If passing for signatures, had to be passed to the proper segways if not the signatory himself.
My Secret plant did not actually require me ever to do any of that…I was cleared, but not required to do such work. My dad was TS same plant but he had actual classified to do.