If you still feel this doctor is operating unethically, I suggest you contact and consult with an expert in your area before deciding that the public is being endangered. Hope this helps. He was less concerned about the next room directly behind the bucky as it is the exam room and no one is there during Xray exams. And he did say sheetrock does pose some protection. He was more concerned about the small grocery store next door to the right of the tube and several feet of wall space away.
Concrete block is also more than the minimum required.
Other variables include placement of the equipment in the room, direction of the central ray, etc. The most important area to have leaded is the wall the tube is shooting at. I would also worry about my x-ray film in the dark room. Here in WA in order to get a license for an x-ray machine, a physicist must be consulted, to determine of how much and where lead shielding is to be installed. This sentence demonstrates the fallacies this thread is drawing very well.