I just graduated from Purdue University with a B.S. in Health Physics. Medical Physics and Health Physics sound similar since they are both about radiation safety and tend to be lumped together in the same program but they are vastly different career paths.
As a health physicist you're looking at job pertaining to the safe use of radiation or safely working in an environment with potential exposure to radiation. So thats like power plants, waste processing, regulations and lab management. Whereas medical physics pertains more to how can that rafiation be used tp accomplish a goal. So that's more oncology, nuclear medicine, radiology, lab scientist, that stuff.
As far as degree level. In my limited experience in job searching a bachelors is acceptable but a masters is generally preferred. Based on my classmates choices a bachelors in medical physics is generally just a stepping stone, a masters or even a doctorate is expected. Especially if you're going the oncology path.
As for pay and benefits it's a pretty wide spread based on where you work. I saw health physicist jobs in one state advertising 45 thousand salary and the same kind of job in another state advertising 70 thousand. I myself am hopefully about to start a job with great pay and benefits but since I'm not even fully hired yet I'm not sure what details I can go into.
I know this post is pretty old but if you have any questions send me a pm.