This text is designed to instruct the student radiographer on the principles of radiation protection biology and the safe administation of X-rays for diagnostic and therapeutic purposes. It covers the skills necessary to ensure the safety of both patient and equipment administrator. The book can also serve as a reference on the safe use of X-rays and includes a comprehensive overview of the science's history. Some of the new subject matter covered includes: the effect of low-level radiation; patient dose consideration and new imaging techniques for mammography; compensating filters; the use of carbon reduction; additional radiographer protection devices; and the biological effects of radiation from such nuclear accidents as Three Mile Island and Chernobyl.