When the Pressure Loss Report command is started, we can choose which fields should appear in our report.
We can also choose which fields are displayed for our duct pressure losses per section, as well as those for our duct fittings and accessories.
When we generate our duct pressure loss report, we will see our duct section numbers, as well as the critical path. To determine which duct section the report extracts information from, we can select our duct and look at our Mechanical Properties.
The above method does work, however: Imagine how long it would take, even on a small scale project, to identify and remember what section number belongs to which duct! There is a workaround: Tags.
We can create a dedicated Duct Pressure Loss Tag family which will graphically show all our required pressure loss calculation results, such as the Section, Pressure Drop, Velocity, as well as Velocity Pressure.
Duct Fittings works a bit differently though. We do not have all of the parameters available as we do have for ducts. We need a workaround: We can simply add the Mark parameter to our Duct Fitting Pressure Loss Tag.
These tags we can add in a plan view, but we will struggle to tag hidden sections, for example a riser and a dropper duct with all of its fittings.
It is often easier to rather create a dedicated 3D view in which we can see what we tag, and what their values are.
I predominantly work on a laptop, so I tile my Revit and Pressure Loss Report windows to easily see what values are applicable to which duct segment. Working on dual screens will make this task much easier!
UPDATE (2016.01.07): A question was asked regarding multiple taps on a single duct. The software still recognizes that even though one has a single duct, wherever a tap occurs, a new duct section is created. The Duct Section, Pressure Loss, Velocity Pressure and Velocity values changes accordingly.