Connect 4" Horizontal Main to 2" Horizontal Shower/Tub

[Dohc]

I am trying to understand the proper connection for a 4" horizontal main to a 2" horizontal shower/tub line. There is about a 6 to 8 inch drop while at the same time transitioning from the 2" tub/shower into the 4" main. See photos of two options that I could come up with. Note the photo does not show the needed 2 x 10 perpendicular joist that will be installed, one on each side of the 4 inch main.

Option one is a 22.5 degree elbow with a combo T. The combo T would be installed at about 22.5 degrees.




Option two is a 90 degree elbow connected to a sanitary T. The Sanitary T would be pointed straight up.



Are either of these options ok? One better than the other?

Thank you

 

[Terry]

You can't use a santee on the waste line into the 4". The first picture with the combo is better.
Venting on the horizontal is supposed to be a wye or combo, but some places allow a santee for that. Your inspector should let you know which he will approve.