an employee at my office used to date a firefighter. She asked them to keep their sirens down because they went right by her window every day.
That just made them turn up their sirens all the time in non-emergency moments as well!
A firefighter friend once told me sirens used during the night were so people knew the agency was out and actually responding to an emergency while they were sleeping comfortably in their beds. I believe that to be true.
We used to get bitched at when I was with a EMS service for running Red Lights and Sirens while going to a call in the early morning.
It made us make more noise....if we’re up...then everyone is up, damnitt.