A few years ago i did a room conversion for a linear accelerator at a private Hospital in Southern California.

There was not much to it. There was an existing concrete maze which we reinforced (meaning radiation penetration, not structural) with tons and tons of lead on the walls and ceiling sitting inside of a steel frame which was then bolted to the concrete maze. The equipment and all of its accessories were placed according to the manufacturer which is usually very specific. We converted an underused and unnecessary hallway into the control center and designed some straight forward casework for the control equipment based on interviews with the operators and techs. The manufacturer wanted everything in place before they come install their machines.

My best advice is make friends with the contractor building the room and one of the techs at the manufacturer of the equipment. There is not that many different ways to do these things and both of them will probably have had experiences with the different problems that arise during your own project.

If you have any specific questions ask away, it has been a few years since i did any hospital work but I might remember a thing or two.

Good Luck.