[binary_slinger]

Some trades are more physically demanding on the body. I was thinking more along the lines of any field that requires a gov't license like nurse/counselor/barber/pharmacist/CPA/lawyer/administrator/teacher/air traffic controller/operator of some heavy machinery.

[schmookeeg]

last time I looked you had to apply to the ATC academy before turning 31. FYI for those considering the big trade: staring at a rectangular screen for staring at a squircle screen instead. :)