You need a good science/anatomy background and must be able to understand radiation physics. Physics was the hardest part for most everyone. I would choose to do this career again, only just wish I started sooner. I am 46 and have done for three years. You do see some blood and bodily fluids so you got to be able to handle that if working in an ER. Some patients really want to ham it up it seems and really want to be babied. That can wear on your nerves but that kind of behavior is scarce and can be learned to be dealt with.