Yes it is different in Virginia. We don't have individual fire departments. We have one fire department, which in my case is Chesterfield County Fire Department, then we have individual stations periodically located throughout the county. When I think of "primary" I think of who usually responds. For example, there isn't a spot in the county where Chesterfield Fire/EMS doesn't service, but there are smaller rescue squads, like Manchester Rescue Squad, that have the same response areas as a county fire station. Occasionally, Manchester will get dispatched if an ambulance for a surrounding station is not available. The way I thnk of it, Chesterfield is the primary service provider, and Manchester would be one of the secondary service providers. I guess the way you worded things confused me, especially when you said Rural/Metro is the primary provider of Niagara Coounty, since they only respond in Lockport. I suppose though you would be right because once I sat down and started thinking about what it was like in Clinton County (I lived there for 16 years before moving to VA) CVPH EMS is a primary service provider in the county, even if they only service Plattsburgh and the surrounding area. You know, now that I thnk of it, does Rural/Metro get dispatched on 46.06 in Niagara County? I have family in Middleport and of all the times I've monitored comms on 46.06, I can't ever recall hearing a dispatch for Rural/Metro. And, btw, I got all my info on loactions that Rural/Metro serves direct from Rural/Metro's website.
Okay, rambling is done.