How to define a certain color code for an intranet?

I've been tasked with preparing a set of rules for the design standard of a collection of intranet modules. Most of these applications are already in production, and new ones are expected to be added in the future as well.

I've already found plenty of resources available in guiding me towards writing a flexible, yet concrete set of rules, but there is one aspect that I cannot find specific advice on, and that is a color code.

While I recognize that a common color code in itself is a secondary consideration within the development of a design standard, it is necessary here because among the current modules of our intranet that are in production, there is too much inconsistency in choices of color usage.

Here is a relevant piece of advice I've found from a university talk on Effective Visual Communication for GUIs:

The importance of color is to communicate. Therefore color codes should respect existing cultural and professional usage... Color connotations should be used with great care.

Bottom Line

I need to create a color guideline using our brand colors, backed by some sort of authoritative and non-biased convention, but I cannot find a single "best-practice" that I can back my decision with in order to minimize office politics.

Our brand colors that we generally use outside of greyscale are the following:

#FE5815 #FFA02F #C4D600 #509E2F #005BBB #001A70 enter image description here