Chicago Code changed a few years ago into 1999NEC with some changes...and they're doozies.
For example, NEC700 has been changed into something almost unrecognizable. Fortunately their Code books are organized and numbered just like NEC, so finding things is a lot easier.
I usually figure in what NEC requires, then whip out my Chicago book to see if I need to change my approach.
It's at least a couple of zillion times better that the OLD Chicago Code, that was basically a minimally updated 1957 code. Chicago even insisted that THEY approve products; not trusting UL with the safety of their fair city...and or course charging for those reviews.
If you're considering an approach that would save time or people, you may find something in Chicago Code against it. This is still a "keep everybody busy" town.
