My father was a volunteer firefighter and EMT for over 20 years - 5 of those as chief - in the small town where I grew up.
Being a small town, a lot of the calls were either traffic accidents, medical, or rural burns that got out of hand. There were very few structure fires over his tenure. In fact, I only remember three that were truly serious.
My father was a high school teacher. The school was 2 blocks from the fire station. As a teacher, he was allowed a reserved parking space near the entrance, but he parked on the street with his car facing the station. If he had to leave for a fire call, it saved him time to just jump in the car and pull straight out. The students all knew it was "Mr. C's Spot" and left it for him.
He wore a pager all the time. If there was an emergency call, it would start with a loud, high-pitched beep, then the dispatcher would announce something like "Paramedic One, Eaton Fire, respond to reports of fall victim at 111 Main Street." Paramedic One was the ambulance team assigned to our area from the local hospital. They were at least ten minutes away from any medical call, so the fire department was the first on scene any time there was an ambulance called.
If it was lunch, or planning period, or close to the end of the school day, my dad would go to the call. Or, on the rare occasion of a structure fire, or a call to dispatch that there were no EMTs to go on a medical call, he would get the principal to cover his classes and go in the middle of the day.
A lot of the volunteers worked shifts at nearby plants, enough so there were a variety of people available even during business hours - though a lot of them would rather have been sleeping. Some of them owned businesses near the firehouse, or worked for the town in other capacities. Because it was a small town, employers tended to be very forgiving. Also because of the nature of the town, it wasn't every day an employee had to run out for a call.
There were certain busy times. In the spring, farmers burn the accumulation of weeds out of their irrigation ditches in preparation for spring planting. Every time, there would be some idiot who left a ditch burning while he went into the house for dinner, and came back out to find the fire had gotten out of control. For a few weeks every spring, we could count on 3-5 nights a week, having our dinner interrupted by ditch fires.
When we were under a tornado warning, the volunteers had to take the trucks each on different routes out of town - so if the station got hit by a tornado, the vehicles were still available to help with the situation. More than once, my mother, brother and I rode out a close call with a tornado in the basement, not knowing if my dad would come home from this one.