I am working on a building in Minnesota built in 1924. The majority of the building is clay tile concrete joist construction, but there is a portion that is a steel framed roof.
The snips attached show steel joist designations that we initially thought were junior steel beams, but we are not...
bones206 - you appear to be correct, I've pulled my posts, my intent was not to spread misinformation. If others think it's usual for discussion, they can post them again.