One of the first movies I ever saw(still one of my favorites),along with the Towering Inferno,Emergency and Code Red,when I was little.The funny thing is how much has changed and how much is STILL the same.Going to You Tube as we speak,lol.
I worked in Colorado Springs in th 70's and I am sure someone must have based this on the 2 competing private ambulance services we had. One of the owners was a short bleach blonde, chain smoking woman who cussed like a sailor. She was right out of central casting for this movie!. This is a classic for us old school EMS guys!