When does a p-trap become an s-trap? – GreenBuildingAdvisor

Hello,

I would like to fix two problems with my sink drain: 1) increase the drain speed, and 2) reduce noise. In the figure, I show the current configiration and it shows that I need to deal with a wall drain oulet that is quite low. I am wondering if changing to the proposed configuration (right part of the figure) would essentially create an s-trap. What I want to know is when a p-trap becomes an s-trap. If the drain pipe in the wall is vertical, then this means that at some distance from the p-trap, it is ok to have a vertical pipe, provided that it is vented. How far is this distance? Would my configuration work if the distance “D: is long enough? How long?

Thanks a lot.

Louis