2/28/2013 - Staff Sgt. Carl Doan, 628th Medical Group diagnostic imaging craftsman, prepares to administer an X-ray examination Feb. 27, 2013 at Joint Base Charleston – Air Base, S.C. As a diagnostic imaging specialist, Doan has the ability to take X-rays of an entire body and has expert knowledge of human anatomy. (U.S. Air Force photo/Airman 1st Class Tom Brading)

2/28/2013 - Staff Sgt. Carl Doan, 628th Medical Group diagnostic imaging craftsman, practices administering an X-ray to Staff Sgt. John Bartlett, 628th MDG medical technician, Feb. 27, 2013 at Joint Base Charleston – Air Base, S.C. Doan is focusing on the cervical vertebrae, or c-spine, which is located in the upper body and is typical of neck injuries. (U.S. Air Force photo/Airman 1st Class Tom Brading)

2/28/2013 - Staff Sgt. Carl Doan, 628th Medical Group diagnostic imaging craftsman, practices administering an X-ray Feb. 27, 2013 at Joint Base Charleston – Air Base, S.C. X-rays are a form of electromagnetic radiation and use the physical properties of the ray to create an image that can be developed for a radiologist. (U.S. Air Force photo/Airman 1st Class Tom Brading)

2/28/2013 - Staff Sgt. Carl Doan, 628th Medical Group diagnostic imaging craftsman, practices administering an X-ray to Staff Sgt. John Bartlett, 628th MDG medical technician Feb. 27, 2013, at Joint Base Charleston – Air Base, S.C. Bartlett is simulating a facial trauma patient with injuries to the jaw, face, nose and eyes. (U.S. Air Force photo/Airman 1st Class Tom Brading)

2/28/2013 - Staff Sgt. Carl Doan, 628th Medical Group diagnostic imaging craftsman, practices administering an X-ray to Staff Sgt. John Bartlett, 628th MDG medical technician, Feb. 27, 2013 at Joint Base Charleston – Air Base, S.C. Bartlett is receiving a chest radiograph, which is used to diagnose conditions affecting the chest, its contents and nearby structures. (U.S. Air Force photo/Airman 1st Class Tom Brading)