Our time starts at dispatch.
We have no control over dispatching, as that is done by county government, and all EMS agencies are independent non-profit.
The county dispatching program, which we have access to, keeps track of when the phone rings, and then all associated unit times. Our charts have spaces for all those times. Our PI person does keep track, and makes charts and graphs.
There have been many times where the answer to dispatch times have been 2-5 minutes, which is totally unacceptable. Prior to advanced dispatching programs, experienced dispatchers hers could send out a call in about 45 seconds. As soon as the dispatcher could figure out the municipality, everything else was simple.
Now, all the information must be entered into the program, and it decides who to send. Only the computer can decide, due to ambulance and fire consolidations, and "closest available" ALS unit. So were are at the mercy of the dispatcher/typist. Also, the dispatcher has to ask all the questions on the flip cards, as they do priority dispatching and pre-arrival instructions.
We get "yelled at" if it takes more than 3 minutes to respond, but there are always extenuating circumstances. Main reason is very old low band radio dispatching. Many times, pagers will not activate inside the hospitals. Some dispatchers will place the ambulance available on arrival at the hospital (not good). Other dispatchers won't put you available when you call in (even worse). Actual responding times are not heavily criticized, as we can go blocks in the city, or miles in the country.