Well, I was,
I worked for a volunteer org in NYC for a while. Then, I worked for what is called a Voluntary Hospital in the NYC 911 system. Basically, NYC FD/EMS (At the time I started, it was still the Health and Hospitals Coporation that oversaw the NYC EMS system) contracts with hospitals in the NYC area to provide a certain amount of ambulance hours to cover a specified geographic location, which generally encompasses the Hospital. This way, the city doesn't have to pay for ambulances, ambulance crews, and supplies for that area, because the hospital provides them. The crews are trained similarly, and are controlled by NYC Protocal, and NYC FD/EMS supervisors. It's just the voluntary hospitals have the hospital name on the side of the ambulance, instead of NYC FD/EMS. The dispatcher, adn the 911 number are the same, and you never know what type of ambulance will show up at your door.
Well, that was my little lesson. But, I don't do that anymore, but I am into carputers.
Is that even what you asked. I don't know, but you can count me in as an Ex-EMT/EMS member.