Outside work as part-time employee

Outside work as part-time employee

I am having trouble finding the University policy (or would this be a funding agency policy?) related to performing professional work outside of the university on a part-time or consulting basis for postdocs. I have found many detailed documents regarding the policies for faculty, but fail to find any related to postdoctoral scholars.

Does anyone know where I should look? Or, what are the constraints?

Thank you.