Fixture Units from a pipe fitting

Hi guys,

I have a question and unfortunately the solution is not easy but I’ve found very kind and smart people here so I think (and I hope) someone will know the answer because it’s really important for me.

Let me explain my question with an example (see also my attached pics):

For the domestic cold water system, I have two WCs. Each WC has associated 1 Fixture Unit. So the total amount is 2 Fixture Units.
Do you think it’s possible to read from the Tee all the Fixture Units associated to the pipes that are connected to the Tee?
Sometime pipe fittings like Bends, Tees and Crosses are not connected directly to the pipes because there are reducers in between pipes and pipe fittings (like in the first pic).
So I don’t know what would be a solution.

Please guys… I really need a help. =(
(and thanks to all the people that have already helped me!!!)
This forum is like a big family.

I’m sure there is a solution…