I'm sure different states have different rules, but I believe a parking brake and emergency brake are one and the same. It's supposed to be designed to hold the entire weight of the vehicle on any slope and also bring you to a stop in the event of a hydraulic brake failure. It also is required to be a secondary mechanical device. In OK, the emergency brake is supposed to bring you to a complete stop from 20 MPH in a certain distance. Not sure what that distance is.
I suspect that if your state has similar rules, the inspector isn't going to have you throw the e-brake, break out a tape measure and see how many feet it took you to stop. They're probably just going to take a quick look and check it off on their inspection checklist.