Shower Vent to Main Vent joint

[GRJack]

Please see atached pics.

I am joining the shower vent to the main vent.
Due to framing obstructions, can I join the vents like in pic. A
with the shower vent dropping (only 3-4 inches) before it tees into
the main vent (my concern is the high point of the shower vent is
higher than the tee- do sewer gases like to collect in this high area instead
of venting out?) or do I have to join them like in pic. B?

Also, for this joint can I just use a regular tee (or sani tee) or do I need
a 'vent tee'.

[jadnashua]

As I understand it, the vent must essentially run up from the trap, it can't have any downward leg. Condensation or a backup could fill it and then block it.

[hj]

Plan B is the official way, using any kind of tee you want to. Plan A will also work, but would not pass an inspection.