Radon Mitigation Inspections

I am on the last section of the Commercial Inspection Course, reading the standards for inspection of Radon Mitigation systems and find no reference for obtaining the plans for the design of the system that was installed in the building where the inspection is taking place.
I would think that it would be next to impossible to come to any sort of analysis of the system when the inspector of a finished building can only see a small percentage of the components of the the mitigation system, maybe just a fan on a vent stack thru the roof labeled Radon Mitigation system without any knowledge of the origin of the piping.
Shouldn’t there be some request for the original documents for that system or is it implied that this would be obtained from the document request from the Commercial Inspection document request (assuming the Radon portion is an add-on to the full building inspection)?