I went to a restaurant last week and had to rebuild the drain on their bar sink which drains into a floor drain.
It was 1-1/2" copper with tight 90's and no clean outs. The bartenders keep dropping straws down the drain and clogging them. And there is no easy way to repair.
I rebuilt the drain long sweeps, clean outs etc.... All good but I used ABS pipes.
Now that I've walked home and am thinking about it I wonder, about half of the restaurants seem to have copper, and the other half ABS.
Just because they use ABS does not mean that it's valid.....
Location: Sacramento, CA