Bob, thanks. But is it REQUIRED?
Depends on AHJ near you.
In Chicago the airgap devices are required but high loops accepted.
Hell with code as I would recommend it.
After looking at it again Joe, I would say yes. If the trap is cloged, the drain will back up until it reaches the DW drain line and then run back into the DW. The reason the high loop goes up to the bottom the flood rim is so when there is a backup you will see the water in the sink.
I totally disagree.
I tell all my clients how to fix/repair most simple defects, and explaining a high loop installation takes me approximately 15 seconds.
In Illinois, yes.
If your AHJ goes by IRC, then yes. Loop should extend to underside of counter. Sinks without disposers can back up too