I'm an air traffic controller at Fort Worth Center, (ARTCC). I can't speak for all types of facilities but I pretty much can for EnRoute facilities like mine. First of all, if you are having symptoms of stomach flu or something like that, you will preplan this factor into your positioning. By this I mean that there are certainly times in which unless there is a real emergency, you may not be able to leave a radar position for 30-45 minutes because it is just too busy. We've all had those days from one time or another. On those days you would humbly avoid the busy rushes and take a position that would allow for a "quick get-a-way."
For your second question, "how long do they work a day?" I've been a center controller for thirteen years now, both at Cleveland Center and presently at Fort Worth Center. I've also been in two different work specialties/areas in each facility. The specifics of work assignments/crews usually change each year and are negotiated by management and the union. The number of specific work schedules are only limited by ones imagination and negotiating power as long as they meet a couple of requirements. 1. You have to work a forty hour week. 2. You can't work more than six days in a row. 3. You have to have eight hours off between shifts. 4. You can't work more than ten hours in a day. 5. You have the staffing to cover the peak traffic times.
Below is the schedule that I am currently on and have been for the last year. It is typical of what's called your rotating shift schedule.
Thursday 14:30 to 22:30
Friday 13:30 to 21:30
Saturday 0800 to 1600
Sunday 06:30 to 14:30
Sunday night mid 22:30 to 06:30 Monday morning.
As you can see there's two days where you have a "quick turn" but you also have a nice weekend break, (although it's not on a real weekend).
If you are interested in learning more about air traffic controllers please feel free to stop by my website and take a look around. There's a lot of information there. We have a new forum section as well and would like to invite the pilots out there to feel free to ask any ATC related question you may have about specific routes or ATC clearances you seem to always get but don't quite understand why.
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