I am getting different answers to this question,from different experts.
Can the closet arm on a DWV pipe has a Y for a clean out or must it be closed?

I'm installing a toilet on the first floor. The toilet is the last fixture on the line. The closet fitting is connected to a short 3" pipe, into a 3x3x2 tee for the vent, then into a 45 deg fitting, and into the 3" "Y" . The "Y" is connected to the main 4" drain line. This Y has a clean-out at the top of the line. Is this legal?