There is something seriously wrong the with the idea that its ok to underpay these very important jobs because they can eek out a living wage by working every hour of their waking life, sacrificing mental and physical health to do so.

Firefighters and teachers are normally overtime exempt salary.

And it's not really fair to nurses to say "you only get a fair wage if you're putting in 60-80 hours". It's also not fair to their patients, as care quality drops pretty hard when you over work nurses and doctors.