I guess Dean was taking one for the team. How else can you get an x-ray than to go into the device. How about when someone gets an MRI and gets bombarded with huge doses of radiation. Remember, this is a low radiation device. Dean will not be glowing int he dark. Its probably about the same as getting a dental x-ray.
Yeah, I've thought about that. I'm sure he's an occupational rad worker but that still doesn't mean it's good to dose yourself - or that the state is cool with it.
That said, I may or may not have done a similar thing during the calibration of a flouro machine many many years ago ("Look at my hand! That's so effin' cool!"). No one is perfect ;-)