look at these burned people

[velshtein]

Before using the machines in your lab, assuming you are the student, you will need the instruction and permission of a qualified person. Most institutions also have some sort of health physics functionary who will want to show you pictures of people who have burned their fingers or arms or eyes through accidental use of X-rays.

--X-Ray Diffraction and the Identification and Analysis of Clay Minerals (Duane M. Moore and Robert C. Reynolds, Jr)

TEXTBOOK, YOU ARE TOO NONCHALANT ABOUT SOME THINGS.