Fluid pressure drop question?

Aug 2019
I need to do pressure drop test for some flow components. Is there a ISO standard or something that I should follow? I'm a little concerned about the placement of the pressure sensors at the inlet and outlet..
Any advice would be nice. Thanks in advance.
Apr 2015
Somerset, England
Are you not using a differential manometer ?

Then pressure sensors would not be needed.

Otherwise you need to follow the manufactures's instructions for sensor placement as their shape and size will determine this and any correction factors for flow obstruction.