Labeling Electrical Heat Trace circuits in a chemical plan.

I am doing some electrical heat trace in a chemical plan for a huge project.
There are many pipes in the project with different names. Some of my power
modules are not near any vessels and my heat trace goes across serveral pipe
line names.
Is there a standard way to label my electric heat trace circuits? If there
is a website that dicusses electrical heat trace labeling in a chemical plan
please let me know. If there is no stardard naming sytem. What is the
best way to label them? Please give an example.

Thank you,